Fundamental skills Flashcards

Question

You are evaluating a patient who has suffered a severe brain injury and unfortunately no measures have led to improvement of the patient’s condition. He is currently on comfort cares and as you observe, his breathing pattern consists of a prolonged pause at full inspiration. Where does this breathing pattern localize the injury? A. Diffuse forebrain B. Thalamus C. Pons D. Medulla E. Upper cervical spine

Answer 1

A. Diffuse forebrain B. Thalamus **C. Pons** D. Medulla E. Upper cervical spine ## Footnote This breathing pattern is apneustic breathing, suggestive of destruction to the pons. Further Reading: Siddiqi. Neurosurgical Intensive Care, 2017, page 340.

Answer 2

A. 20 mL/100 g/min B. 35 mL/100 g/min **C. 50 mL/100 g/min** D. 75 mL/100 g/min E. 100 mL/100 g/min ## Footnote CBF in the normal, healthy adult is thought to be around 50 mL/100 g/min. Further Reading: Siddiqi. Neurosurgical Intensive Care, 2017, page 424.

Answer 3

A. 20 mL/100 g/min B. 35 mL/100 g/min C. 50 mL/100 g/min D. 75 mL/100 g/min **E. 100 mL/100 g/min** ## Footnote Pediatric patients have elevated cerebral blood flow, and it can be as high as 108 mL/100 g/min and it can stay this elevated through the teenage years. Further Reading: Siddiqi. Neurosurgical Intensive Care, 2017, page 424.

Answer 4

A. Bronchogenic carcinoma **B. Small cell lung cancer** C. Medullary thyroid cancer D. Neuroblastoma E. Medulloblastoma ## Footnote Small cell lung cancer has the ability to form peptide hormones, including antidiuretic hormone (ADH), which can lead to syndrome of inappropriate antidiuretic hormone secretion (SIADH) and hyponatremia. urther Reading: Bernstein, Berger. Neuro- Oncology: The Essentials, 3rd edition, 2015, page 451.

Answer 5

A. Skin biopsy **B. CSF antineuronal antibodies** C. CSF anti-Jo antibodies D. CSF anti-RI antibodies E. CSF glucose ## Footnote Neuropsychiatric SLE can manifest with multiple symptoms. The diagnosis can be made by testing for ANA in the cerebrospinal fluid (CSF). Further Reading: Kanekar. Imaging of Neurodegenerative Disorders, 2016, page 221.

Answer 6

A. Alexander’s disease **B. CADASIL** C. PML D. Symptomatic carotid stenosis E. Multiple embolic infarcts ## Footnote This MRI demonstrates findings classic for cerebral autosomal dominant arteriopathy with subcortical infarcts. This is thought to occur due to regional hypometabolism due to a genetic abnormality on chromosome 19. Patients have a progressive declining course and often die between 50 and 70 years of age. Further Reading: Kanekar. Imaging of Neurodegenerative Disorders, 2016, page 220.

Answer 7

**A. Inflammation** B. Thrombosis C. Embolic infarct D. Arterial rupture ## Footnote This patient has giant cell arteritis, also known as temporal arteritis. Blindness is a feared complication when this condition is left untreated, and it occurs via inflammation and progression of disease to include the ciliary arteries and central retinal artery. When inflamed, they can lead to ischemic optic neuropathy and blindness. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 249.

Answer 8

A. Clopidogrel B. Heparin **C. Prednisone** D. Hydroxychloroquine E. Infliximab ## Footnote Giant cell arteritis is an inflammatory vasculitis and blindness can be a complication of this condition. These patients should be treated with prednisone initially. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 249.

Answer 9

A. 300 B. 310 **C. 320** D. 330 E. 340 ## Footnote Mannitol should no longer be administered in patients who have a serum osmolality of 320 or greater as the risk of ATN increases substantially. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 762.

Answer 10

A. Epidermoid cyst B. Eosinophilic granuloma C. Growing skull fracture **D. Calcified cephalohematoma** E. Nonaccidental trauma ## Footnote This CT scan demonstrates evidence of a calcified cephalohematoma, a bleed located between the periosteum and the skull. It becomes bound by suture lines. In the majority of cases, these resolve in 1 to 3 days; however, they can persist and calcify, sometimes requiring surgery. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 798.

Answer 11

**A. Further observation** B. Surgical decompression C. Needle aspiration D. Serial CT scans E. Tight head wrap ## Footnote At this point, the child is stable and more observation should be recommended. The hematoma may continue to resolve over time. Needle aspiration should be avoided unless there is concern for infection due to the risk of iatrogenic infection. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 799.

Answer 12

**A. 5%** B. 15% C. 35% D. 55% E. 75% ## Footnote Retinal hemorrhages are very common in non- accidental trauma, and very rare in accidental brain trauma, occurring in 5% or less of accidental traumas. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 803.

Answer 13

A. < 10 minutes **B. < 70 minutes** C. < 120 minutes D. < 6 hours E. < 24 hours ## Footnote According to current evidence, decompression should be achieved within 70 minutes of the onset of pupillary changes in patients with EDH, highlighting the emergent nature of this condition. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 749.

Answer 14

A. 7-mm thick/4-mm midline shift **B. 12-mm thick/6-mm midline shift** C. 3-mm thick/3-mm midline shift D. 9-mm thick/2-mm midline shift E. 13-mm thick/1-mm midline shift ## Footnote According to current guidelines, any acute subdural hematoma that measures greater than 10 mm in thickness and is associated with greater than 5 mm of midline shift should be surgically evacuated regardless of GCS. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 753.

Answer 15

A. Prednisone **B. NSAIDs** C. Ketamine D. Methotrexate E. Temozolomide ## Footnote There is currently no role for steroids in the treatment of brachial neuritis. These patients are managed conservatively and NSAIDs can be used for shoulder pain. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 736.

Answer 16

A. 50% B. 60% C. 70% **D. 90%** E. 100% ## Footnote Brachial neuritis is managed conservativelyand most patients experience a full recovery at 3 years. The rate of recovery is around 90%. Supportive care and extensive physical therapy should be utilized in this condition. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 736.

Answer 17

A. Seizures B. Agitation **C. Bradycardia** D. Hypertension E. Tachycardia ## Footnote Precedex is an alpha-2 agonist in the CNS that can be used for sedation. It has dose-dependent effects on blood pressure and heart rate, specifically causing hypotension and bradycardia. Further Reading: Siddiqi. Neurosurgical Intensive Care, 2017, page 160.

Answer 18

A. Raphe nucleus B. Nucleus accumbens C. Periaqueductalgray **D. Locus ceruleus** E. Solitary tract ## Footnote Precedex is a central alpha-2 agonist that is thought to exert its effects on the locus coeruleus in the brainstem, mediating arousal and sleep–wake cycles. Decreasing transmission of the neurons in this nucleus that are primarily noradrenergic causes sedation and diminishes agitation. Further Reading: Siddiqi. Neurosurgical Intensive Care, 2017, page 161.

Answer 19

A. 1 hour B. 6 hours C. 12 hours **D. 24 hours** E. 48 hours ## Footnote Currently, the FDA has only approved continuous infusion of Precedex for 24 hours given the risk of rebound hypertension and tachycardia after cessation of administration. Further Reading: Siddiqi. Neurosurgical Intensive Care, 2017, page 161.

Answer 20

A. Hypertension **B. New right bundle branch block** C. Seizures D. Metabolic alkalosis E. Hypokalemia ## Footnote Propofol infusion syndrome is thought to occur in patients receiving high-dose propofol infusion for more than 48 hours. The exact mechanism is unknown but thought to be due to metabolic derangements in the mitochondria. Initial find- ings can include a right bundle branch block. It can go on to include hypotension, bradycardia, metabolic acidosis, rhabdomyolysis, and hypokalemia. Propofol should be stopped. Further Reading: Siddiqi. Neurosurgical Intensive Care, 2017, page 159.

Answer 21

A. Propofol **B. Etomidate** C. Ketamine D. Pentobarbital E. Isoflurane ## Footnote Etomidate is an anesthetic agent that decreases CMRO2 and cerebral blood flow. It also causes adrenocortical axis suppression and decreases the concentration of ACTH. Further Reading: Albright, Pollack, Adelson. Prin- ciples and Practice of Pediatric Neurosurgery, 3rd edition, 2015, page 740.

Answer 22

**A. Patent foramen ovale** B. Pre-existing DVT C. Restrictive lung disease D. History of cervical fusion E. Ongoing cervical radiculopathy ## Footnote The sitting position can be useful in neurosurgery, but there is an increased risk of venous air embolism. A patient with a PFO is a relative contraindication for the use of the sitting position due to the risk of a right-sided air embolism becoming a left-sided embolism. Further Reading: Albright, Pollack, Adelson. Principles and Practice of Pediatric Neurosurgery, 3rd edition, 2015, page 142.

Answer 23

A. Propofol B. Pentobarbital C. Etomidate D. Midazolam **E. Methohexital** ## Footnote Methohexital is an anesthetic agent that lowers the seizure threshold. It is sometimes used during electrocorticography for surgical treatment of epilepsy. Further Reading: Baltuch, Villemure. Operative Techniques in Epilepsy Surgery, 2009, page 48.

Answer 24

A. ~ 25% B. ~ 33% C. ~ 40% **D. ~ 60%** E. ~ 90% ## Footnote In patients with refractory temporal lobe epilepsy (TLE), surgical treatment can lead to 60% seizure freedom at 1 year post-op, compared to 8% seizure freedom in patients undergoing medical management alone. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 269.

Answer 25

A. Permanent motor deficit **B. Temporary motor deficit** C. Initial seizure worsening D. High risk of infection E. High risk of postoperative hemorrhage ## Footnote Multiple subpial transections can be performed as a palliative epilepsy surgery in patients with medically refractory epilepsy. It severs the horizontal intracortical connections, but preserves neurons due to the vertical columnar orientation. These patients should expect to have transient neurologic deficit for several months postoperatively. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 272.

Answer 26

A. Medial frontal lobe B. Occipital lobe **C. Temporal lobe** D. Lateral frontal lobe E. Parietal lobe ## Footnote The rising epigastric sensation and déjà vu can be associated with TLE. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 264.

Answer 27

Which of the following factors is more consistent with type II or atypical trigeminal neuralgia? A. Lancinating pain B. Pain-free intervals C. Unilateral **D. Throbbing pain** ## Footnote Type I, or classic TN, usually presents with sharp, lancinating unilateral pain with pain-free intervals. In studies on the subject, type I patients were more likely to have arterial compression at surgery as well as better long-term outcomes than type II patients, which tend to have persistent, burning/aching/throbbing pain that can be bilateral, and may be associated with other pathologies, such as multiple sclerosis. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 294.

Answer 28

A. 25% B. 65% C. 75% **D. 85%** E. 95% ## Footnote According to current literature, up to 84% of patients with type I TN pain will experience excellent to good pain control with microvascular decompression surgery. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 294.

Answer 29

A. 25% **B. 65%** C. 75% D. 85% E. 95% ## Footnote Patients with atypical type II TN may still benefit from microvascular decompression. Up to 65% of these patients will have “excellent to good” pain control long term. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 294

Answer 30

A. Balloon compression B. Radiofrequency rhizotomy C. Microvascular decompression **D. Medical management** E. Glycerol rhizotomy ## Footnote This patient has TN and has not yet undergone any treatment. Initial management should be with carbamazepine, as 80% of patients will experience nearly immediate relief (within 24–48 hours) with this medication. The pain relief diminishes over time, and over the long term, only 50% of patients may have continued relief on carbamazepine. Up to 10% of patients may not tolerate carbamazepine. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 295.

Answer 31

**A. Voltage-gated sodium channel blockade** B. Voltage-gated calcium channel blockade C. Mu opioid receptor agonist D. NMDA receptor agonist E. GABA agonist ## Footnote Oxcarbazepine is a sodium channel blocking pain medication that works in a similar fashion to carbamazepine. It can be used in some patients that cannot tolerate standard carbamazepine. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 295.

Answer 32

A. Superior B. Inferior **C. Lateral** D. Medial E. Intermediate ## Footnote The distribution of the V1, V2, and V3 divisions of the trigeminal nerve is oriented in the foramen ovale in a superomedial to inferolateral direction. Therefore, to best treat V3 pain, the catheter should be placed lateral within the foramen. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 297.

Answer 33

A. A 67-year-old woman with breast cancer **B. A 55-year-old male alcoholic** C. A 42-year-old male IV drug user D. An 18-year-old woman with lymphoma E. An 80-year-old woman with carotid stenosis ## Footnote This image demonstrates central pontine myelinolysis (CPM), also known as osmotic demyelination syndrome. Patients with alcoholism can experience severe alterations in electrolytes, which could lead to CPM. Further Reading: Rohkamm. Color Atlas of Neurology, 2007, page 310.

Answer 34

A. Hypokalemia **B. Hyperkalemia** C. Hypomagnesemia D. Hypercalcemia E. Hypernatremia ## Footnote Hyperkalemia can cause tall, peaked or spiked T waves on ECG Further Reading: Citow, Macdonald, Refai. Comprehensive Further Reading: Citow, Macdonald, Refai. Comprehensive Neurosurgery Board Review, 2nd edition, 2010, page 519.

Answer 35

A. Hyponatremia **B. Hypocalcemia** C. Hyperkalemia D. Hypernatremia E. Hypermagnesemia ## Footnote Hypocalcemia can be associated with lengthening of the PR interval on ECG. Further Reading: Citow, Macdonald, Refai. Comprehensive Neurosurgery Board Review, 2nd edition, 2010, page 520.

Answer 36

A. Prolonged PR interval B. ST elevation **C. Multifocality** D. QRS prolongation E. Bundle branch block ## Footnote Hypomagnesemia can cause multifocality on ECG. Further Reading: Citow, Macdonald, Refai. Comprehensive Neurosurgery Board Review, 2nd edition, 2010, page 520.

Answer 37

**A. Cortical-based tumor** B. Symptoms for 4 hours C. History of seizures D. Age of 18 years E. Platelet count of 115,000 ## Footnote The presence of an intracranial tumor, aneurysm or arteriovenous malformation (AVM) is absolute contraindication to the administration of IV rtPA for acute ischemic stroke. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 10.

Answer 38

A. Caudal loop **B. Choroidal point** C. Cranial loop D. Spinal point E. Extradural segment ## Footnote PICA originates from the vertebral artery and supplies the brainstem and cerebellum. After the choroidal point, PICA is supplying only cerebellum and if needed could be taken with minimal side effects. Proximal to this point, a medullary infarct will likely occur. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 16.

Answer 39

**A. Superior thyroid** B. Ascending pharyngeal C. Lingual D. Facial E. Occipital ## Footnote The superior thyroid artery is the first branch of the external carotid artery. It is commonly seen and needs to be controlled during carotid endarterectomy. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 32.

Answer 40

A. Ophthalmic B. Anterior ethmoidal C. Posterior ethmoidal **D. Sphenopalatine** E. Vidian ## Footnote The sphenopalatine artery is the primary vascular supply to the nasal cavity. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 35.

Answer 41

**A. 4%** B. 8% C. 12% D. 20% E. 33% ## Footnote Patients with aneurysmal subarachnoid hemorrhage (SAH) with an unsecured aneurysm are at risk of rebleed, which can have devastating consequences. The risk in the first 24 hours is roughly 4%. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 45.

Answer 42

A. 10 to 15% **B. 15 to 20%** C. 20 to 25% D. 25 to 30% E. 30 to 35% ## Footnote There is an elevated risk of aneurysm rebleed in the first 2 weeks after rupture if the aneurysm remains unsecured. That risk is approximately 15 to 20%. The mortality of aneurysm rebleed is near 75%. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 45.

Answer 43

A. Iatrogenic fluid overload **B. Catecholamine surge** C. Heart failure D. Pulmonary embolism E. Prolonged mechanical ventilation ## Footnote Neurogenic pulmonary edema can occur after aneurysmal SAH and close pulmonary monitoring should occur in these patients. While pulmonary edema can occur from iatrogenic fluid overload, neurogenic pulmonary edema is thought to be due to an acute catecholamine surge experienced after the bleeding event. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 46.

Answer 44

A**. Hyponatremia** B. Hypernatremia C. Hypocalcemia D. Hyperkalemia E. Hypokalemia ## Footnote The most common electrolyte disturbance in SAH is hyponatremia, which can occur via two mechanisms, either cerebral salt wasting (CSW) or SIADH. It is important to determine volume status to differentiate between SIADH and CSW. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 47.

Answer 45

A. Posterior communicating artery B. MCA bifurcation **C. Anterior communicating artery** D. Basilar tip E. Posterior inferior cerebellar artery ## Footnote Occasionally patients with SAH can present with hypernatremia, caused by diabetes insipidus. This may be suggestive of an anterior communicating artery aneurysm due to destruction of hypothalamic pathways involved in the production and release of ADH. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 47.

Answer 46

A. Aggressive glucose control B. Decreasing IV infusions C. TPN administration **D. Early enteral nutrition** E. Regular sedation holidays ## Footnote Intubated SAH patients have high rates of gastrointestinal (GI) stress ulcer formation and should all be placed on GI prophylactic medications. Early enteral nutrition via either percutaneous gastrostomy or nasogastric tube can allow for early feeding, thus decreasing stress ulcer formation. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 47.

Answer 47

A. Mortality B. Continued refractory ICP elevation C. Good outcome and decreased ICP **D. Poor outcome and decreased ICP** E. Good outcome but increased ICP ## Footnote The DECRA trial was performed in Australia in 2011 and demonstrated that patients who underwent decompressive craniectomy (DC) had improvement in their ICP and shorter intensive care unit (ICU) stays, but overall had poorer outcomes than standard care. The trial has been criticized for having too aggressive a surgical arm with ref- ractory ICP defined as 20 mm Hg for more than 15 minutes. This may have led to more patients being operated than necessary. The Randomised Evaluation of Surgery with Craniectomy for Uncontrollable Elevation of Intracranial Pressure (RESCUEicp) trial is ongoing and has increased the time frame required to determine refractory ICP elevation. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 776.

Answer 48

A. No change **B. Decreased hematoma volume; no clinical effect** C. Decreased hematoma volume; improved clinical course D. Increased hematoma volume; no clinical effect E. Increased hematoma volume; improved clinical course ## Footnote The INTERACT trial aimed to determine if intensive blood pressure control had significant effects on clinical outcome. Intensive blood pressure control (systolic blood pressure [SBP] < 140) decreased overall hematoma size, but it did not have any effect on clinical course. INTERACT 2 is ongoing. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 229.

Answer 49

A. 2 times **B. 5 times** C. 10 times D. 50 times E. 100 times ## Footnote According to current literature, baseline hypertension with SBP > 160 leads to a 5.5 times higher risk of spontaneous ICH compared to patients with good blood pressure control. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 231.

Answer 50

A. 0% **B. 20%** C. 50% D. 75% E. 100% ## Footnote ICH can be a devastating event, and many patients develop neurologic deficits following this event. The rate of functional independence 3 months after the bleeding event occurs is roughly 20%. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 231.

Answer 51

A. 13% B. 26% C. 72% D. 97% **E. 100%** ## Footnote This patient has suffered a devastating cerebellar hemorrhage that will have a 100% 30-day mortality according to the ICH score. Points are awarded for age older than 80 years, infratentorial location, IVH, hematoma volume greater than 30 mL, and 1 point for GCS 5 to 12. This gives her 5 of a total of 6 points. Patients with an ICH score of 5 or 6 have a 100% 30-day mortality. Patients with a score of 4 have a 97% 30-day mortality. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 231.

Answer 52

A. Right hemisphere location B. Age younger than 80 years **C. Superficial cortical (< 1 cm from the surface) location** D. No midline shift E. Intraventricular extension ## Footnote In the initial STICH trial, there was no benefit from surgical resection of spontaneous cerebral hemorrhage when compared to standard medical therapy. Upon subgroup analysis, there may be a benefit to resecting a cerebral hemorrhage with a superficial location and significant mass effect. STICH II examined cases of lobar hemorrhage, however, and found no improvement in outcome between the surgical and medical arms of treatment. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 232.

Answer 53

**A. Hypertension** B. Age older than 80 years C. Metastatic disease D. Smoking E. Drug use ## Footnote This CT scan demonstrates a cerebellar hemorrhage with intraventricular extension. The most common underlying cause for this disorder is uncontrolled hypertension. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 235.

Answer 54

A. 0% B. 25% **C. 50%** D. 75% E. 100% ## Footnote This patient has a spontaneous cerebellar hemorrhage and the data suggest that there is a 50% chance of good outcome (Glasgow Outcome Score 4 or 5, meaning no requirement for assistance in activities of daily living) in patients treated surgically for this condition. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 236.

Answer 55

A. Hypertension (SBP > 160) B. Hematoma enlargement on serial CT scan C. GCS 15 **D. Hydrocephalus** E. Elevated INR ## Footnote According to American Heart Association (AHA)/American Stroke Association (ASA) ICH guidelines, the presence of neurological deterioration, brainstem compression and/or the presence of hydrocephalus should make you strongly consider surgical resection of the hematoma and decompression of the posterior fossa. CSF diversion should also be utilized during the surgery. EVD placement alone without hematoma resection is not recommended. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 237.

Answer 56

A. 1 cm B. 2 cm **C. 3 cm** D. 4 cm E. 5 cm ## Footnote Three centimeters has been identified as a rough cutoff whereby patients with a hematoma smaller than 3 cm in dimension are less likely to deteriorate and require surgical intervention compared to patients with a hematoma greater than 3 cm. This is not a hard and fast rule, however, and many other factors, including location, brainstem compression, medical comorbidities, and other systemic characteristics, play into the surgical AU2 n making from patient to patient. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 237.

Answer 57

A. Glioblastoma B. Hypertension **C. Vasculitis** D. Metastatic disease E. Ischemic stroke ## Footnote This pathologic specimen demonstrates arterial wall necrosis and monocytic infiltration of the vessel walls. There is associated granuloma formation. These findings are consistent with vasculitis. Conventional angiogram may demonstrate arterial nicking. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 253.

Answer 58

A. CSF overproduction B. Arachnoid granulation dysfunction C. Aqueductal stenosis D. Multiple subclinical hemorrhages **E. Decreased ventricular compliance** ## Footnote NPH is characterized by ambulatory difficulties, cognitive impairment, and urinary incontinence in patients with ventriculomegaly but normal CSF pressure. The full underlying mechanism is not well understood, but thought to be due to poor craniospinal compliance of the ventricular system, at least in part. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 324.

Answer 59

A. Ventriculomegaly on MRI B. Adequate CSF flow on cine MRI C. Leukocytosis **D. Improved gait after high-volume LP** E. Perceived cognitive improvement after highvolume LP ## Footnote In patients with suspected NPH, high-volume lumbar puncture (LP) should be performed (30–50 mL removed), and gait analysis should be performed immediately after this procedure. Patients who had gait improvement after LP had the highest rate of overall symptom improvement after permanent VP shunt placement. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 326.

Answer 60

A. Pilocytic astrocytoma B. Optic glioma C. Epidermoid cyst **D. Arachnoid cyst** E. Metastatic disease ## Footnote This patient has an arachnoid cyst of the right sylvian fissure. The cyst contents have the same signal intensity as CSF and this is helpful for the diagnosis. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 349.

Answer 61

A. Improvement in ICP and clinical outcome, no systemic complications B. Improvement in ICP and clinical outcome, increased systemic complications C. No improvement in ICP, improved clinical outcome, increased systemic complications D. Improvement in ICP, no clinical improvement, increased systemic complications **E. No improvement in ICP, no clinical improvement, increased systemic complications** ## Footnote Similar to adult TBI, there is no role for systemic steroids in pediatric patients that have severe TBI. Clinical and ICP outcomes show no difference and patients are exposed to systemic risk with steroid administration. Further Reading: Harbaugh, Shaffrey, CouldwellBerger. Neurosurgery Knowledge Update, 2015, page 398.

Answer 62

A. 18 to 20 weeks of gestation **B. 24 to 26 weeks of gestation** C. 30 to 32 weeks of gestation D. 36 to 38 weeks of gestation E. 40+ weeks of gestation ## Footnote Currently, fetal surgery for the repair of myelomeningocele occurs at 24 to 26 weeks of gestation. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 403.

Answer 63

A. ICU admission and observation B. Intensive blood pressure management C. Intensive glucose management **D. Further imaging** E. PMR assessment ## Footnote This is a young patient with no significant risk factors for spontaneous ICH. The age, lack of risk factors, and odd location of this hemorrhage should make you concerned for an underlying vascular malformation or aneurysm. A CT angiogram (CTA) should be obtained as a start, and likely a formal catheter angiogram to follow depending on the CTA findings. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 422.

Answer 64

A. Neurofibromatosis type I B. Kennedy’s disease **C. Hereditary hemorrhagic telangiectasia** D. Ataxia-telangiectasia E. Von Hippel–Lindau disease ## Footnote The catheter angiogram demonstrates a cerebral AVM. Of the listed choices, HHT is associated with AVM formation. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 424.

Answer 65

**A. < 10%** B. 11 to 20% C. 21 to 30% D. 31 to 40% E. 41 to 50% ## Footnote With successful indirect or direct bypass in patients with moyamoya disease, the 5-year rate of stroke drops from 67 to 90% to less than 10%. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 424.

Answer 66

A. Baseline visual field tests **B. Optic chiasm involvement** C. Enhancement pattern on MRI D. Location (right vs. left) E. Patency of retinal artery on angiogram ## Footnote Optic gliomas in patients with NF1 can be surgically resected en bloc (or nearly en bloc) if it is obvious that there is normal optic nerve on either side of the involved area. In these cases, the tumor can be resected with the optic nerve (and orbit); however, if there is tumor invasion into the optic chiasm, the mass cannot be completely excised without unacceptable risk of bilateral blindness postop. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 429.

Answer 67

**A. Moment arm** B. Bony fracture C. Ligamentous damage D. Load E. Stress shield ## Footnote Spine biomechanics can be helpful to understand when evaluating traumatic injury to the spine. Forces are applied to the spine in force vectors. When one of these vectors is applied at a given distance from an axis of rotation, a moment arm is created. This moment arm depicts a lever that starts from the IAR to the force application. This property helps explain compression fractures versus burst fracture pathology. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 451.

Answer 68

A. Change in unit length/original length **B. Force applied per unit area** C. Length of moment arm D. Overall weight (in kg) applied to the instantaneous axis of rotation E. Resistance of the object to deformation ## Footnote Stress is defined as force applied per unit area. Strain is defined as change in unit length compared to original length. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 452.

Answer 69

A. The area under the force deformation curve **B. The slope of the most linear region of the force deformation curve** C. The point of maximum force on the force deformation curve D. The point of maximum deformation on the force deformation curve ## Footnote Stiffness of the implant is defined as the slope of the line on the force deformation curve. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 453.

Answer 70

A. Fracture B. Ultimate strength **C. Yield point** D. Preloading E. Breaking point ## Footnote The point on the force deformation curve where the implant begins to deform but has not yet undergone complete failure is called the elastic zone. The point where the device enters the elastic zone is termed the yield point. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 454.

Answer 71

A. 10% B. 25% C. 50% D. 75% **E. 95%** ## Footnote Development of spondylosis in the spine is a normal aspect of aging, and approximately 10% of patients aged 25 years will have spondylosis on imaging, with this percentage increasing to 95% by 65 years of age. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 458.

Answer 72

A. Facet hypertrophy and nerve root impingement B. Disc herniation **C. Excitation of recurrent sinuvertebral nerve endings** D. Loss of disk height E. Increased disk vascularity ## Footnote Discogenic axial back pain is a controversial issue, especially regarding treatment options, but is thought to occur due to excitation of the sinuvertebral nerve (a branch from the anterior ramus) that innervates the posterior longitudinal ligament (PLL) and annulus. In patients with spondylosis, irritation, and inflammation of the various structures of the ventral canal are thought to excite these fibers and generate pain. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 458.

Answer 73

A. Recurrent sinuvertebral nerve B. Anterior spinal nerve ramus **C. Posterior spinal nerve ramus** D. Gray ramus communicans E. White ramus communicans ## Footnote Facetogenic axial back pain is controversial, but pain from the facet joints is thought to arise from innervating fibers from the posterior ramus of the associated spinal nerve. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 458.

Answer 74

A. 400-mg calcium, 400-IU vitamin D B. 800-mg calcium, 800-IU vitamin D **C. 1,200-mg calcium, 1,000-IU vitamin D** D. 2,000-mg calcium, 2,000-IU vitamin D E. 3,000-mg calcium, 4,000-IU vitamin D ## Footnote According to NOF guidelines, women older than 50 years should receive 1,200 mg of calcium on a daily basis as well as 1,000 IU of vitamin D. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 487.

Answer 75

A. Inhibits osteoblasts **B. Inhibits osteoclasts** C. Promotes osteoclasts D. Promotes osteoblasts E. Provides structural framework for bone formation ## Footnote Calcitonin antagonizes parathyroid hormone and therefore inhibits osteoclast activity. This decreases bone resorption and helps strengthen bones. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 487.

Answer 76

A. Increased risk of heart attack B. Increased risk of breast cancer **C. Increased risk of DVT** D. Increased risk of esophagitis E. Increased bleeding tendencies ## Footnote Raloxifene is a selective estrogen receptor modifier that is used for bone health. It simultaneously decreases risk of breast cancer and inhibits bone resorption. Patients should be aware of the increased risk of DVT with the administration of raloxifene. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 487.

Answer 77

A. Acetaminophen **B. NSAIDs** C. Oxycodone D. Ketamine E. Dexamethasone ## Footnote In patients with inflammatory spondyloarthropathies, patients can be treated with NSAIDS that both decrease associated pain and modify the disease process, through a process that is not entirely known, but likely involves decreasing inflammation. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 535.

Answer 78

**A. Hemangioblastoma** B. Meningioma C. Schwannoma D. Neurofibroma E. Astrocytoma ## Footnote Intramedullary spinal cord tumors can have an associated syrinx. The most common intramedullary tumors associated with a syrinx are hemangioblastoma and ependymoma. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 584.

Answer 79

A. Bladder dyssynergy B. Decreased bladder compliance C. Altered sensation **D. Detrusor hyperreflexia** ## Footnote Tethered cord syndrome can have orthopedic, neurologic, and urologic problems. Of the urologic problems, detrusor hyperreflexia is the most common. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 585.

Answer 80

A. 30% B. 50% **C. 65%** D. 80% E. 95% ## Footnote Bone is made of 20% water, but the dry weight of bone is 35% organic material and 65% inorganic material. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 626.

Answer 81

**A. Calcium phosphate** B. Calcium carbonate C. Fluoride derivates D. Trace elements ## Footnote Calcium phosphate compounds make up 85% of inorganic bone material. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 625.

Answer 82

A. Osteoclasts B. Osteogenic progenitor cell **C. Osteoblasts** D. Osteocytes E. Pericytes ## Footnote Parathyroid hormone works to enhance bone resorption, but it does this by stimulating osteoblasts. In turn, the osteoblasts release osteoclast stimulating factor, which activates the osteoclastic resorption process. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 626.

Answer 83

A. Osteoconduction **B. Osteogenesis** C. Osteoinduction D. Arthrodesis ## Footnote Osteogenesis refers to the cellular component of bone fusion, and osteogenesis gives the bone graft the ability to form new bones. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 626.

Answer 84

**A. Osteoconduction** B. Osteogenesis C. Osteoinduction D. Arthrodesis ## Footnote Osteoconduction refers to providing a solid matrix for new bone formation. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 626.

Answer 85

A. Osteoconduction B. Osteogenesis **C. Osteoinduction** D. Arthrodesis ## Footnote Osteoinduction refers to the process of fusion where precursor or immature cells are induced to differentiate into mature bone-forming cells. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 626.

Answer 86

A. Sciatic B. Superficial peroneal **C. Common peroneal** D. Femoral E. Obturator ## Footnote In this posterior location, the sciatic, common peroneal, and tibial nerves are at risk. When the laceration is just above the knee in a lateral position, it would be more likely for the patient to have suffered a common peroneal nerve injury as the peroneal and tibial nerves have bifurcated from the sciatic. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 655.

Answer 87

A. Infectious disease consult B. Neurology consult **C. Vascular surgery consult** D. PMR consult E. Social work consult ## Footnote With a confirmed nerve injury in a sharp lacer- ation such as depicted above, you should strongly consider a vascular surgery consult given that nerves often run in close approximation with major blood vessels. There is also an associated hematoma apparent in the wound. You would not want to expose the nerve and discover a major vascular injury that you were not prepared for. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 565.

Answer 88

A. Smoking history B. BMI **C. Presence of nerve continuity** D. Grade of motor deficit E. Presence of fasciculations ## Footnote The presence or absence of peripheral nerve continuity is the most important initial factor to determine when evaluating a traumatic nerve injury as it governs potential for recovery. If the nerve is in continuity, it should be given time to heal and serial electromyograms (EMGs) will be performed to determine if there are nerve potential across the area of damage. If present, conservative management will likely be recommended. If the nerve is completely severed, earlier surgical reconstruction will likely be performed. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 655.

Answer 89

A. Immediately B. 3 days **C. 3 weeks** D. 3 months E. 1 year ## Footnote Gunshot wounds to the peripheral nerves often cause neurologic deficit via indirect or pressure-wave-related phenomena. In 85% of cases, the nerve remains intact. In the case where the nerve has been severed, the surgeon should wait 3 to 4 weeks to perform a nerve graft repair. If another surgical team is planning to explore the wound, the two ends of the severed nerve should be tagged for easier identification and to decrease retraction for the definitive secondary repair. Waiting for 3 to 4 weeks allows the injured nerve tissue to degenerate and then at reoperation the nerve can be resected back to healthy tissue to facilitate a repair. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 655.

Answer 90

A. Brain MRI B. Head CT C. Silent EEG D. Perfusion studies **E. Detailed neurological examination** ## Footnote The diagnosis of brain death can be both con- troversial and difficult, but generally speaking the only requirement for the diagnosis of brain death is a detailed neurologic examination making sure multiple factors are met prior to the performance of the examination. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 825.

Answer 91

A**. PaCO2 > 60 mm Hg (or 20 mm Hg greater than baseline)** B. PaCO2 > 50 (or 25 mm Hg greater than baseline) C. PaCO2 > 5 0 (or 10 mm Hg greater than baseline) D. PaCO2 > 40 (or 10 mm Hg greater than baseline) E. PaCO2 > 40 (or 10 mm Hg greater than baseline) ## Footnote There are several aspects to the brain death evaluation, and the apnea test is one of the tests. The patient should be preoxygenated and a blood gas should be drawn. The ventilator is then stopped for 8 to 10 minutes or until hypoxia and/or hypotension occurs. Another blood gas is drawn and if the PaCO2 is greater than 60 mm Hg or has risen more than 20 mm Hg above baseline, the test is positive. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 825.

Answer 92

A. Decreased mortality, worsened hearing **B. Decreased mortality, improved hearing C. No change in mortality, improved hearing** D. No change in mortality, worsened hearing E. Increased mortality, worsened hearing ## Footnote Corticosteroids have been studied as an adjunct during treatment of meningitis. A Cochrane review demonstrated no change in overall mortality, but that there was a reduction in hearing loss. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 833.

Answer 93

A. Electrolyte panel **B. Albumin concentration** C. Erythrocyte sedimentation rate D. Complete blood count E. BNP level ## Footnote You can use serum albumin concentration to help determine volume status in patients that you are trying to determine CSW versus SIADH. Patients with SIADH will have normal albumin concentrations, while patients with CSW will be hypovolemic and will have increased albumin concentrations. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 842.

Answer 94

A. SIADH B. Motor deficit **C. Seizures** D. Intraparenchymal hemorrhage E. Aphasia ## Footnote This patient has posterior reversible encephalopathy syndrome (PRES), and along with significant encephalopathy, these patients have high rates of seizures and hypertension. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 851.

Answer 95

A. Nitric oxide release B. Impaired corticospinal tract function C. Blood loss **D. Unopposed vagal tone** E. Pain ## Footnote Neurogenic shock is thought to arise after spinal cord injury due to sympathetic deafferentation, which leads to unopposed tone from the vagal nerve, causing hypotension and bradycardia. Further Reading: Siddiqi. Neurosurgical Intensive Care, 2017, page 103.

Answer 96

A. SBP **B. Heart rate** C. Urine output D. Blood cultures E. Diastolic blood pressure ## Footnote In neurogenic shock, there is hypotension and bradycardia, whereas in hemorrhagic shock, you would expect to see hypotension and tachycardia. Further Reading: Siddiqi. Neurosurgical Intensive Care, 2017, page 103.

Answer 97

A. < 24 hours **B. < 48 hours** C. < 72 hours D. < 1 week E. < 1 month ## Footnote The STICH II trial randomized patients to early surgery (< 48 hours) for superficial ICH and the characteristics listed in the question stem. There was a small survival benefit with surgery, but no change in morbidity. The patient and/or family members should be counseled regarding the outcome of surgical resection of ICH. Further Reading: Siddiqi. Neurosurgical Intensive Care, 2017, page 116.

Answer 98

A. More cases of good functional outcome **B. No change in good functional outcome** C. Fewer cases of good functional outcome D. Decreased mortality, more cases of poor functional outcome E. Decreased mortality, fewer cases of poor functional outcome ## Footnote The CLEAR III trial demonstrated that intraventricular distillation of rtPA in cases of IVH does not lead to any more patients with a good functional outcome. Subset analysis demonstrated that in patients who had 20 mL of evacuated blood, there was a 10% increase in good functional outcome. Further Reading: Siddiqi. Neurosurgical Intensive Care, 2017, page 116.

Answer 99

A. Levetiracetam **B. Pentobarbital** C. Carbamazepine D. Lorazepam E. Ketamine ## Footnote This EEG demonstrates a burst-suppression pattern. Of the listed medications, pentobarbital is the most likely to be utilized in a patient to achieve this EEG pattern. Further Reading: Siddiqi. Neurosurgical Intensive Care, 2017, page 177.

Answer 100

A. Labetalol B. Nicardipine **C. Hydralazine** D. Esmolol E. Diltiazem ## Footnote Hydralazine is an antihypertensive that causes direct arteriolar vasodilation as a mechanism of action, and therefore would not be a good choice of antihypertensive in a patient with elevated ICP. Further Reading: Siddiqi. Neurosurgical Intensive Care, 2017, page 248.

Answer 101

A. ~ 5% B. ~ 10% C. ~ 20% D. ~ 30% **E. ~ 50%** ## Footnote There is an increased energy demand after severe neurologic injury. Some studies have sug- gested that the basal energy expenditure in TBI patients is 46% higher than normal expected values. Patients require elevated levels of nutritional support while recovering from neurologic injury. Further Reading: Siddiqi. Neurosurgical Intensive Care, 2017, page 276.

Answer 102

A. NitricBeta blockade B. Oxide release **C. Calcium channel blockade** D. Alpha blockade ## Footnote Nicardipine is a calcium channel blocker used for control of hypertension. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 126.

Answer 103

A. True ## Footnote Nitroglycerin is a vasodilator and has been shown to raise intracranial pressure (ICP). Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 126.

Answer 104

B. False ## Footnote Labetalol is an alpha-1 selective and beta nonselective blocker that either maintains ICP or reduces it. It has not been shown to increase ICP. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 126.

Answer 105

**A. Phenylephrine** B. Norepinephrine C. Dobutamine D. Epinephrine ## Footnote Phenylephrine is a pure alpha agonist that has no beta inotropic effects and therefore it constricts arterioles. It tends to decrease cardiac output and can decrease renal blood flow. It should be avoided in spinal cord injuries unless absolutely necessary. Better choices would be a medication with inotropic effects. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 128.

Answer 106

A. A1 B. A2 **C. B1** ## Footnote The B1 receptor, when activated, leads to increased cardiac contractility and therefore increased cardiac output based on + inotropy. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 128.

Answer 107

A. Morphine **B. Warfarin** C. Levetiracetam D. Acetazolamide ## Footnote Omeprazole is a proton pump inhibitor (PPI) that inhibits certain P450 enzymes in the liver that can alter the metabolism of warfarin. Care should be taken when prescribing omeprazole to patients on anticoagulation with warfarin. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 130.

Answer 108

B. False ## Footnote Remifentanil is a rapid acting formulation of fentanyl that crosses the blood–brain barrier (BBB) in less than 1 minute. It lowers ICP. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 133.

Answer 109

A. Raphe nucleus **B. Locus coeruleus** C. Nucleusaccumbens D. Periaqueductal gray ## Footnote Dexmedetomidine (Precedex) is an alpha-2 agonist that acts primarily in the locus coeruleus. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 134.

Answer 110

A. Factor III B. Factor VII **C. Proteins C + S** D. Factor IX ## Footnote In the initial days of warfarin therapy, patients can actually become hypercoagulable owing to the inhibition of proteins C + S, which are vitamin K–dependent anticoagulation factors. Therefore, bridging therapy should be considered in at-risk patients initiating warfarin therapy. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 164.

Answer 111

A. 0% B. 30% **C. 60%** D. 100% ## Footnote With a confirmed nerve injury in a sharp lacer- ation such as depicted above, you should strongly consider a vascular surgery consult given that nerves often run in close approximation with major blood vessels. There is also an associated hematoma apparent in the wound. You would not want to expose the nerve and discover a major vascular injury that you were not prepared for. Further Reading: Harbaugh, Shaffrey, Couldwell, Berger. Neurosurgery Knowledge Update, 2015, page 565.

Answer 112

**B. Decreases** ## Footnote CO2 is a potent cerebral vasodilator, and therefore during hyperventilation, the PaCO2 drops and cerebral blood flow decreases. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 104.

Answer 113

**A. 7%/1 degree** B. 25%/1 degree C. 33%/1 degree D. 50%/1 degree ## Footnote Hypothermia decreases the cerebral metabolic rate of oxygen (CMRO2 ) by approximately 7% per 1 degree of temperature decrease. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 104.

Answer 114

Isoflurane B. Desflurane **C. Nitric oxide** D. Sevoflurane ## Footnote All of the inhalational neuroanesthetic drugs decrease cerebral metabolism except for nitric oxide. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 104.

Answer 115

A. True ## Footnote True, the inhalational anesthetic agents disturb cerebral autoregulation and cause vasodilation, which increases ICP. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 104.

Answer 116

A. > 30 minutes B. > 1 hour **C. > 2 hours** D. > 5 hours ## Footnote It is thought that use of inhalational anesthetic agents for more than 2 hours can lead to increased production of CSF, exacerbating any potential ICP issues. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 104.

Answer 117

A. Isoflurane B. Desflurane **C. Nitric oxide** D. Sevoflurane ## Footnote Nitric oxide is 34 times more soluble than nitrogen, and in cases where pneumocephalus or air embolism can occur, nitric oxide should be avoided as it can expand as it is evolved out of the blood stream and greatly increase the pressure within a confined space, causing tension pneumocephalus or further embolism. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 105.

Answer 118

**A. Isoflurane** B. Remifentanil C. Nitric oxide D. Propofol ## Footnote Isoflurane is a halogenated inhalational anesthetic agent. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 105.

Answer 119

**A. 10 minutes** B. 30 minutes C. 1 hour D. 2 hours ## Footnote Nitric oxide can cause tension pneumocephalus as it evolves out of the bloodstream in an enclosed space. It should be discontinued at least 10 minutes before the dural is closed in a water tight fashion. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 105.

Answer 120

**A. Isoflurane** B. Desflurane C. Nitric oxide D. Sevoflurane ## Footnote Isoflurane is a halogenated inhalational anesthetic that can be used to create an isoelectric EEG without reaching levels causing metabolic toxicity. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 105.

Answer 121

A. Isoflurane B. Desflurane C. Nitric oxide **D. Sevoflurane** ## Footnote Sevoflurane is a halogenated inhalational anesthetic that can have decreased cardiac inotropic effects, decreasing cardiac output. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 105.

Answer 122

A. Hypertension **B. Hypotension** C. Tachycardia D. Bradycardia ## Footnote Propofol will cause a dose-dependent decrease in blood pressure and ICP. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 105.

Answer 123

A. Sodium thiopental **B. Methohexital** C. Etomidate D. Isoflurane ## Footnote Methohexital is a barbiturate anesthetic that can be used for induction. It can lower the seizure threshold, so it should be used sparingly in patients with seizure disorders. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 105.

Answer 124

B. False ## Footnote Etomidate is an imidazole anesthetic agent that can be used for induction of anesthesia. It has anesthetic and amnestic effects, but it is important to remember that it does not have any analgesic effects. Further Reading: Greenberg. Handbook of Neuro- surgery, 8th edition, page 105.

Answer 125

A. Congestive heart failure **B. Intrinsic renal disease** C. Seizure disorder D. Obstructive lung disease ## Footnote Etomidate is an imidazole anesthetic agent that can be used for induction of anesthesia. It has anesthetic and amnestic effects, but it is important to remember that it does not have any analgesic effects. It is known to impair renal function and should be avoided in patients with known renal disease. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 105.

Answer 126

A. Sodium channel B. GABA receptor **C. NMDA receptor** D. Glutamate receptor ## Footnote Ketamine is a dissociative anesthetic that works on the NMDA receptor. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 106.

Answer 127

A. Seizure risk B. Tachyphylaxis **C. Histamine release** D. Nausea induction ## Footnote Synthetic narcotics (fentanyl and derivatives) differ from nonsynthetic narcotics in that they do not cause release of histamine. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 106.

Answer 128

A. Propofol B. Etomidate C. Methohexital **D. Lidocaine** ## Footnote Lidocaine can be given IV, which can suppress laryngeal reflexes, decreasing the ICP spikes during intubation. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 106.

Answer 129

A. True ## Footnote Succinylcholine is the only depolarizing paralytic agent used during anesthetic induction. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 107.

Answer 130

A. Bradycardia B. Decreased end-tidal CO2 **C. Muscle rigidity** D. Seizure ## Footnote While the initial symptom may be an increase in end-tidal CO2 , the classic symptom is muscle rigidity. Further Reading: Greenberg. Handbook of Neuro- surgery, 8th edition, page 108.

Answer 131

**A. Dantrolene** B. Desmopressin C. Epinephrine D. Beta blocker ## Footnote Dantrolene IV infusion is used to treat malignant hyperthermia and can be titrated to decreased symptoms up to 10 mg/kg. Further Reading: Greenberg. Handbook of Neurosurgery, 8th edition, page 108.

Answer 132

A. Elastance **B. Compliance** C. Rigidity D. Stability ## Footnote Cardiac ventricular compliance is the ability of the ventricular wall to distend at a given volume. The same principles apply to CSF ventricular compliance. Further Reading: Marino. The ICU Book, page 5.

Answer 133

A. Increased compliance **B. Decreased compliance** C. Increase elastance ## Footnote Cardiac ventricular compliance is the ability of the ventricular wall to distend at a given volume. The same principles apply to CSF ventricular compliance. Further Reading: Marino. The ICU Book, page 6.

Answer 134

A. Preload B. Contractility **C. Afterload** D. Compliance ## Footnote Afterload is considered the sum of all forces that decrease cardiac ventricular emptying. This sum of forces is essentially made from the impedance caused by the aorta and large arteries. Further Reading: Marino. The ICU Book, page 7.

Answer 135

A. Second **B. Fourth** C. Sixth D. Eighth ## Footnote Poiseuille’s law governs vascular flow and resistance. A commonly tested question, vascular flow varies based on the inner radius of the tube to the fourth power. Further Reading: Marino. The ICU Book, page 11.

Answer 136

A. 2 times B. 4 times C. 8 times **D. 16 times** ## Footnote Poiseuille’s law governs vascular flow and resistance. A commonly tested question, vascular flow varies based on the inner radius of the tube to the fourth power. Therefore, a vessel with 2 times the diameter will have 16 times the flow. Further Reading: Marino. The ICU Book, page 11.

Answer 137

A. True ## Footnote Arterial oxygen content is entirely dependent on saturation of hemoglobin with oxygen. Therefore, a 50% reduction in hemoglobin will lead to a 50% reduction in arterial oxygen content, while a 50% reduction in PaO2 may only lead to a 20% reduction in arterial oxygen content. Further Reading: Marino. The ICU Book, page 21.

Answer 138

B. False ## Footnote Stress ulcers of the GI mucosa are primarily caused by decreased or impaired blood flow, not gastric acidity. The ulcerations are confined to the surface mucosa and tend to be different from ulcers caused by peptic ulcer disease, which are deeper ulcerations, sometimes deep enough to erode through the wall of the GI tract completely. Further Reading: Marino. The ICU Book, page 96.

Answer 139

A. 0% B. 30% C. 60% **D. 90%** ## Footnote There is evidence of early gastric erosion in up to 90% of patients admitted to the ICU by the third day. Patients at higher risk include those with burns affecting 30% of the body surface area and those with head injuries. Further Reading: Marino. The ICU Book, page 96.

Answer 140

A. Systolic pressure **B. Mean arterial pressure** C. Diastolic pressure D. Venous pressure ## Footnote The mean arterial pressure is the best measurement to determine true pressure for peripheral blood flow. It does not change as the waveform progresses distally, and is less affected by distortions from recording systems. Further Reading: Marino. The ICU Book, page 151.

Answer 141

A. Systolic pressure + one-third of pulse pressure B. Systolic pressure + two-thirds of diastolic pressure **C. Diastolic pressure + one-third of pulse pressure** D. Diastolic pressure + two-thirds of systolic pressure ## Footnote Oftentimes, the mean arterial pressure is calculated electronically by modern recording systems, but it can be estimated manually by using the diastolic pressure and adding one-third of the pulse pressure. This calculation is based on a heart rate of 60 beats per minute, and may be incorrectly estimating mean arterial pressure in patients with tachycardia. Further Reading: Marino. The ICU Book, page 151.

Answer 142

Approximately what percentage of total body fluid is located in the intravascular compartment? **A. 10%** B. 25% C. 33% D. 50% ## Footnote The average male has approximately 48 L of total body fluid, and only 10% is located in the intra- vascular space. Further Reading: Marino. The ICU Book, page 207.

Answer 143

A. 4 L **B. 5 L** C. 6 L D. 7 L ## Footnote The average 80-kg male has approximately 5 L of whole blood. Further Reading: Marino. The ICU Book, page 207.

Answer 144

A. 150 mL **B. 750 mL** C. 15 L D. 3 L ## Footnote Class I hypovolemia is clinically asymptomatic hypovolemia, and this is often seen with 1 to 15% of total intravascular volume loss. At approximate- ly 15% or more, clinical symptoms will present, and this is often resting tachycardia. Further Reading: Marino. The ICU Book, page 209.

Answer 145

A. Hypotension **B. Resting tachycardia** C. Pre-syncope D. Delayed capillary refill ## Footnote Oftentimes, the first clinical symptom from acute blood loss/hypovolemia is resting tachycardia. Further Reading: Marino. The ICU Book, page 209

Answer 146

A. 0% **B. 20%** C. 40% D. 60% ## Footnote When patients are hypovolemic, the body will move interstitial fluid into the intravascular space to compensate. When IV crystalloid is given, a significant portion of the salt content moves into the interstitial space, and the fluid follows. Therefore, only approximately 20% of crystalloid fluid volume will remain in the intravascular space. Further Reading: Marino. The ICU Book, page 220.

Answer 147

A. 20% B. 40% C. 60% **D. 80%** ## Footnote Due to oncotic pressure, approximately 80% of colloid volume given through a peripheral IV will remain in the intravascular space. Further Reading: Marino. The ICU Book, page 220.

Answer 148

A. 130 B. 140 **C. 154** D. 161 ## Footnote The concentration of sodium in 0.9% NaCl is 154 mEq. Further Reading: Marino. The ICU Book, page 229.

Answer 149

**A. 130** B. 140 C. 154 D. 161 ## Footnote Lactated Ringer’s solution contains the cations potassium and calcium to better approximate plasma concentrations. It also contains lactate. In order to remain electrically neutral, there must be a reduction in sodium concentration, to 130 mEq. Further Reading: Marino. The ICU Book, page 230.

Answer 150

B. False ## Footnote Twenty-five-percent albumin has a plasma volume expansion ratio of four to five times and while intravascular volume can be repleted, a significant decrease in interstitial fluid volume can occur and the patient may remain significantly hypovolemic even though the parameters normalize. Further Reading: Marino. The ICU Book, page 235.

Answer 151

B. False ## Footnote Albumin solutions are heat treated and therefore there is not risk of viral transmission through the use of albumin. Further Reading: Marino. The ICU Book, page 235.

Answer 152

B. False ## Footnote While colloid solutions are better intravascular volume expanders, there is no evidence that confers a survival benefit in these patients compared to those patients who receive crystalloid resuscitation. Further Reading: Marino. The ICU Book, page 236.

Answer 153

A. Nitroglycerin **B. Nitroprusside** C. Labetalol D. Esmolol ## Footnote Nitroprusside contains 5 cyanide ions in its molecule and cyanide is released into the bloodstream when the medication breaks down into nitric oxide. In order to be cleared, sulfur from thiosulfate is bound to the cyanide, which forms thiocyanate, which can be cleared by the kidneys. Further Reading: Marino. The ICU Book, page 293.

Answer 154

A. Hypovolemia **B. Electrolyte abnormalities** C. Coronary ischemia D. Hypervolemia ## Footnote Postoperative atrial fibrillation can be seen and is often caused by electrolyte abnormalities. Beta blockers may have some benefit in decreasing rates of perioperative atrial fibrillation. Further Reading: Marino. The ICU Book, page 321.

Answer 155

A. > 90 BPM B. > 110 BPM C. > 130 BPM **D. > 150 BPM** ## Footnote Rate control is more important than rhythm control in atrial fibrillation, and when there is a persistent tachycardia greater than 150 bpm, electrical cardioversion should be considered, especially in the setting of corresponding hypotension. Further Reading: Marino. The ICU Book, page 322.

Answer 156

B. False ## Footnote Atelectasis is the collapse of alveoli and leads to a shunt in the respiratory system, not dead space. Further Reading: Marino. The ICU Book, page 341.

Answer 157

A. > 20 mm Hg B. > 32 mm Hg **C. > 46 mm Hg** D. > 65 mm Hg ## Footnote Hypercapnia is diagnosed when the PaCO2 is greater than 46 mm Hg, but it must not be artificially elevated as is the case of a compensatory response to metabolic alkalosis. Further Reading: Marino. The ICU Book, page 350.

Answer 158

**A. Increased pulmonary shunting** B. Increased dead space ventilation C. Hypoventilation D. Increased CO2 production ## Footnote The three main sources of hypercapnia are increased dead space, hypoventilation, and increased metabolic CO2 production. Further Reading: Marino. The ICU Book, page 351.

Answer 159

B. False ## Footnote While many are taught that ARDS represents an acute accumulation of watery edema into the lungs, it is truly an inflammatory process where the alveolar spaces are filled with WBCs, RBCs, and protein debris. Further Reading: Marino. The ICU Book, page 372.

Answer 160

A. 1 to 3 mL/kg B. 4 to 6 mL/kg **C. 7 to 10 mL/kg** D. 11 to 15 mL/kg ## Footnote While previously tidal volumes of 11 to 15 mL/ kg were used during mechanical ventilation, out of concern for barotrauma standard tidal volumes are now 7 to 10 mL/kg. Further Reading: Marino. The ICU Book, page 381.

Answer 161

A. Tidal volume **B. Positive end-expiratory pressure** C. Peak inspiratory pressure D. Respiratory rate ## Footnote Positive end-expiratory pressure (PEEP) can be used to increase arterial oxygen saturation by keeping the alveoli from collapsing at the end of expiration. It is also useful in ARDS. Further Reading: Marino. The ICU Book, page 381.

Answer 162

A. True ## Footnote Positive pressure ventilation can reduce ventricular filling due to positive intrathoracic pressure and compression of pulmonary blood vessels. Further Reading: Marino. The ICU Book, page 424.

Answer 163

B. False ## Footnote Previously, large inflation volumes (10–15 mL/ kg) were used in an attempt to keep the alveoli open, but this led to worsened respiratory conditions due to barotrauma. Currently, lower inflation volumes are used with PEEP to keep the alveoli open. Further Reading: Marino. The ICU Book, page 424.

Answer 164

A. Inflation Volume B. Flow resistance C. Elastic recoil of the lung **D. Respiratory rate** ## Footnote End-inspiratory peak pressure is an important factor in mechanical ventilation, and it is calculated by using the inflation volume, the flow resistance, and the elastic recoil of the lung tissue. Further Reading: Marino. The ICU Book, page 427.

Answer 165

A. True ## Footnote Assist control (A/C) mode on the ventilator allows the patient to trigger breaths but delivers a set inflation volume. If the patient does not trigger a breath in a set amount of time, the ventilator will deliver a breath based on a backup rate. Further Reading: Marino. The ICU Book, page 434.

Answer 166

A. True ## Footnote A/C mode on the ventilator allows the patient to trigger breaths but delivers a set inflation volume. If the patient does not trigger a breath in a set amount of time, the ventilator will deliver a breath based on a backup rate. Further Reading: Marino. The ICU Book, page 434.

Answer 167

A. A patient taking low tidal volumes **B. A patient breathing rapidly** C. A patient taking high tidal volumes D. A patient breathing slowly ## Footnote A/C mode on the ventilator allows the patient to trigger breaths but delivers a set inflation volume. If the patient does not trigger a breath in a set amount of time, the ventilator will deliver a breath based on a backup rate. If the patient is breathing rapidly, the ventilator will continue to deliver set volumes and this can lead to hyperventilation and sever alkalosis or hyperinflation injury. Further Reading: Marino. The ICU Book, page 436.

Answer 168

A. Assist/control B. Intermittent mandatory ventilation **C. Pressure support** D. Volume-controlled ventilation ## Footnote Pressure support ventilation allows the patient to trigger breaths as well as determine the respiratory cycle and inflation volume. It assists with providing inspiratory pressure to augment the inflation volume if necessary. This setting is often used to help wean patients from the ventilator since it allows the patient to demonstrate their capacity to breathe on their own. Further Reading: Marino. The ICU Book, page 440.

Answer 169

**A. Distal airway collapse** B. Restriction C. Obstruction D. Proximal airway collapse ## Footnote PEEP is used to keep the alveoli open during expiration to avoid the end-expiratory pressure from reaching zero, which causes distal airway collapse. By propping open the alveoli, there is better ventilation throughout the respiratory cycle. Further Reading: Marino. The ICU Book, page 442.

Answer 170

**A. Continuous positive airway pressure** B. Bilevel positive airway pressure ## Footnote CPAP is very useful to keep upper airways open during negative pressure inspiration in patients with obstructive sleep apnea. Further Reading: Marino. The ICU Book, page 446.

Answer 171

A. Continuous positive airway pressure **B. Bilevel positive airway pressure** ## Footnote Bilevel positive airway pressure is a useful adjunct for noninvasive ventilation in patients with mild hypercapnia. It provides positive pressure timed in accordance with the change in inspiratory/expiratory pressure in order to keep the distal airways open and improve ventilation. Further Reading: Citow, Macdonald, Refai. Comprehensive Neurosurgery Board Review, 2nd edition, 2010, critical care section.

Answer 172

**A. Inspiration** B. Expiration ## Footnote Almost 90% of patients have laryngeal edema after extubation, but only approximately 2% have severe enough obstruction to require reintubation. Stridorous breathing noted on inspiration is an ominous sign for impending obstruction given that the negative pressure during inspiration is causing dynamic worsening of upper airway obstruction. Reintubation should be strongly considered. Further Reading: Marino. The ICU Book, page 479.

Answer 173

**A. Reintubation** B. 6-mg IV dexamethasone C. Racemic epinephrine D. Tracheostomy ## Footnote Severe upper airway obstruction can be dangerous, and if there is significant concern, immediate reintubation should be performed, followed by possible tracheostomy. IV steroids do not have any effect on improving acute obstruction, and racemic epinephrine has only been shown to work in children. Further Reading: Marino. The ICU Book, page 479.

Answer 174

B. False ## Footnote Fever is a qualitative response to inflammation, not infection, and there is no association between fever and degree of infection. Further Reading: Marino. The ICU Book, page 487.

Answer 175

B. False ## Footnote Early postoperative fever is often attributed to atelectasis, but it has been demonstrated that there is no correlation between the two entities. Even after upper abdominal surgery, where atelectasis is nearly 100% in the first week, only 15% of patients will exhibit an early postoperative fever. Further Reading: Marino. The ICU Book, page 489.

Answer 176

B. False ## Footnote Steroids were commonly used in the past for septic shock but have shown no benefit, and have even demonstrated harm in some cases. They should be avoided in cases of septic shock. Further Reading: Marino. The ICU Book, page 509.

Answer 177

A. Streptococcus pneumoniae **B. Pseudomonas sp.** C. Escherichia coli. D. Klebsiella sp. ## Footnote Pseudomonas is the most common cause of nosocomial, ventilator-associated pneumonia. This differs from community-acquired pneumonia, which is often caused by streptococcus pneumonia. ICU-/ventilator-associated pneumonia is often gram negative. Further Reading: Marino. The ICU Book, page 517.

Answer 178

A. 0.025% **B. 0.25%** C. 2.5% D. 25% ## Footnote Needle stick injuries with blood from an HIV- infected patient carries a risk of transmission of approximately 0.25%. Further Reading: Marino. The ICU Book, page 547.

Answer 179

**A. 0.09%** B. 0.9% C. 9% D. 90% ## Footnote As a care provider if you are exposed to blood from a patient with HIV to a mucous membrane, your risk of transmission is quite low, coming in at approximately 0.09%. Further Reading: Marino. The ICU Book, page 547.

Answer 180

A. Seizures B. Gastric ulceration **C. Nephrotoxicity** D. Cardiomyopathy ## Footnote A. Seizures B. Gastric ulceration C. Nephrotoxicity D. Cardiomyopathy

Answer 181

**A. Seizures** B. Gastric ulceration C. Nephrotoxicity D. Cardiomyopathy ## Footnote Imipenem is a very powerful broad spectrum antibiotic, and the major complication is the development of generalized seizures, which can occur in up to 3% of patients. Further Reading: Marino. The ICU Book, page 566.

Answer 182

A. 10% **B. 30%** C. 50% D. 70% E. 90% ## Footnote The survival rate of cardiopulmonary resuscita- tion (CPR) is low, at 30% overall. There is only a 10% return to baseline function in patients that have CPR performed. Further Reading: Citow, Macdonald, Refai. Comprehensive Neurosurgery Board Review, 2nd edition, 2010, critical care section.

Answer 183

A. True positive **B. True negative** C. False positive D. False negative ## Footnote True negative is when the test you are performing accepts the null hypothesis and the individual has a negative result on the test. For example, your patient tests negative for tuberculosis (TB) and actually does not have TB. Further Reading: http://www.cs.rpi.edu/~leen/ misc-publications/SomeStatDefs.html.

Answer 184

A. True positive B. True negative C. False positive **D. False negative** ## Footnote False negative is when the test you are performing accepts the null hypothesis and the individual does not satisfy the null hypothesis. For example, your patient tests negative for TB but actually does have TB. Further Reading: http://www.cs.rpi.edu/~leen/ misc-publications/SomeStatDefs.html.

Answer 185

**A. Sensitivity = TP/ (TP + FN)** B. Sensitivity = 1 − type I error C. Sensitivity = TN/ (TN + FP) D. Sensitivity = FP/ (FP + TN) ## Footnote Sensitivity is the chance of testing positive among the community of patients with the condition. It is defined as TP/ (TP + FN), or 1–type II error. Further Reading: http://www.cs.rpi.edu/~leen/ misc-publications/SomeStatDefs.html.

Answer 186

A. Sensitivity = TP/ (TP + FN) **B. Sensitivity = 1 − type I error** C. Sensitivity = TN/ (TN + FP) D. Sensitivity = FP/ (FP + TN) ## Footnote Specificity is the chance of testing negative among the community of patients without the disease. It is defined as TN/ (TN + FP), or 1–type I error. Further Reading: http://www.cs.rpi.edu/~leen/ misc-publications/SomeStatDefs.html.

Answer 187

A. Sensitivity = TP/ (TP + FN) B. Sensitivity = 1 − type I error **C. Sensitivity = TN/ (TN + FP)** D. Sensitivity = FP/ (FP + TN) ## Footnote Further Reading: http://www.cs.rpi.edu/~leen/ misc-publications/SomeStatDefs.html.

Answer 188

A. NPV = TP/(TP + FN) B. NPV = 1 − type I error C. NPV = TP/(TP + FP) **D. NPV = TN/(TN + FN)** ## Footnote Negative predictive value is the chance of not having the condition among patients who test negative for the condition. It is defined as TN/ (TN + FN). Further Reading: http://www.cs.rpi.edu/~leen/ misc- publications/SomeStatDefs.html.

Answer 189

A. Type I error = TP/(TP + FN) B. Type I error = 1 − sensitivity **C. Type I error = FP/(FP + TN)** D. Type I error = TN/(TN + FN) ## Footnote Type I error (alpha) is the chance of testing positive among patients who do not have the condition. It is defined as FP/ (FP + TN), or 1–specificity. Further Reading: http://www.cs.rpi.edu/~leen/ misc-publications/SomeStatDefs.html.

Answer 190

A. Type II error = TP/(TP + FN) **B. Type II error = 1 − sensitivity** C. Type II error = FP/(FP + TN) D. Type II error = TN/(TN + FN) ## Footnote Type II error (beta) is the chance of testing neg- ative among patients who do have the condition. It is defined as FN/ (FN + TP), or 1–sensitivity. Further Reading: http://www.cs.rpi.edu/~leen/ misc-publications/SomeStatDefs.html.

Answer 191

**A. NNT = 1/absolute risk reduction** B. NNT = 1/relative risk reduction C. NNT = TP/(TP + FN) D. NNT = TN/(TN + FP) ## Footnote Number needed to treat can be a helpful calculation to make statistics generalizable to patient populations in clinic. It is calculated by using the formula 1/absolute risk reduction (ARR). The ARR is calculated by ARR = (control event rate) − (experimental event rate). Further Reading: http://clincalc.com/stats/nnt.aspx.

Answer 192

A. Power = 1 − type I error **B. Power = 1 − type II error** C. Power = TP/(TP + FN) D. Power = TN/(TN + FP) ## Footnote Statistical power is used to decrease the rate of type II error (false negatives). It is calculated using the formula 1 − type II error. Further Reading: http://www.cs.rpi.edu/~leen/ misc-publications/SomeStatDefs.html.

Answer 193

A. Provide a social work consultation **B. Perform a medical examination** C. Obtain appropriate imaging D. Perform a face-to-face handoff to the receiving physician ## Footnote A hospital must perform an initial medical examination to ensure patient stability prior to transferring the patient to another hospital regardless of ability to pay. Further Reading: https://www.acep.org/news-media- top-banner/emtala/.

Answer 194

**A. True** ## Footnote According to EMTALA, you are required to accept this transfer as the intake hospital does not have subspecialty coverage for this type of emergency and the patient needs to be transferred to your facility for further management and stabilization. Further Reading: https://www.acep.org/news-media- top-banner/emtala/.

Answer 195

**B. False** ## Footnote According to EMTALA, you are required to accept a transfer when a local hospital or ED does not have subspecialty coverage. However, when there are other facilities closer to the hospital in question, the patient should be transferred to the closest facility with appropriate coverage, and you do not have to accept this transfer over such a long distance as there are multiple capable facilities between you and the patient. Further Reading: https://www.acep.org/news-media- top-banner/emtala/.

Answer 196

**A. True** ## Footnote The intake hospital must provide stabilizing care to a patient prior to transfer to a different facility. If a patient is unstable, a physician must certify that the expected benefits outweigh any risks of transfer. Further Reading: https://www.acep.org/news-media- top-banner/emtala/.

Answer 197

**B. False** ## Footnote While all 50 states and the District of Columbia have some form of the Good Samaritan law, specifics can vary. It is important to know that it is designed to encourage health care workers to render emergency aid, but does not provide blanket liability. You can still be charged with gross negligence if you are not providing at least reasonable standard of care in an emergency situation. An example would be initiating emergency care (CPR), but then walking away before emergency medical technicians (EMTs) arrive. Further Reading: http://medicaleconomics.modernmedicine.com/medical-economics/news/ modernmedicine/modern-medicine-now/ liability-risks-good-samaritan?page=full.

Answer 198

**B. False** ## Footnote There are three provisions required for the Good Samaritan law to be in effect. It must be an emergency, you must not be on hospital grounds, and care must be voluntary. Further Reading: http://medicaleconomics.modernmedicine.com/medical-economics/news/ modernmedicine/modern-medicine-now/ liability-risks-good-samaritan?page=full.

Answer 199

**B. False** ## Footnote In this situation, you are covered under the Good Samaritan law and you should provide emergency care that you think is required. If the patient is awake and responsive, it is appropriate and required that you ask for consent. If the patient is unconscious, you can provide emergency care without obtaining prior consent. Further Reading: http://medicaleconomics.modernmedicine.com/medical-economics/news/ modernmedicine/modern-medicine-now/ liability-risks-good-samaritan?page=full.

Answer 200

**B. False** ## Footnote According to the Stark Law against self-referral, physicians are not able to refer patients to facilities in which they have a direct financial benefit from the referral. This law was enacted to decrease resource utilization and conflicts of interest when providing medical care. Further Reading: http://starklaw.org/.

Answer 201

**B. False** ## Footnote According to the Anti-Kickback Statute, it is a criminal offense to provide or promise any financial incentive or anything of value to promote referrals. Further Reading: https://www.healthlawyers.org/ hlresources/Health%20Law%20Wiki/Anti-Kickback%20Statute.aspx.

Answer 202

**B. False** ## Footnote Sending patient information over text messaging in an unsecured violation with specific information is a Health Insurance Portability and Accountability Act of 1996 (HIPAA) violation and should be avoided unless the hospital has provided encrypted capabilities for messaging. Further Reading: http://www.beckershospitalreview.com/healthcare-information-technology/10-common-hipaa-violations-and-preventative-measures-to-keep-your-practice-in-compliance.html.