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1
Q

Propofol infusion syndrome associated with all of the following EXCEPT

  1. Cardiac Failure
  2. Pancreatititis
  3. Rhabdomyolyisis
  4. Thrombocytopenia
A
  • THROMBOCYTOPOENIA
  • Remembering “PRIS” - Propofol infusion syndrome
    • ​P = Pancreatitits
    • R= Rhabdomyoclisis
    • I = Iperkalemia
    • S = Sa_Green_ Urine
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2
Q

Local Anesthetic Systemic Absorption based on injection site from GREATEST to LEAST

A
  • “I Think I Can PEBSS”
    • I = Intravenous
    • T = Transtracheal
    • I = Intercostal
    • C = Caudal
    • P = Paracervical
    • E = Epidrual
    • B = Brachial Plexus
    • S = Sciatic/Femoral
    • S = Subcutaneous
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3
Q

Anesthetic Considerations in Management of Abdominal Aortic Aneurysms.

How does cross clamp time relate to outcome?

  1. Which type carries the greatest risk of spinal and renal ischemia during cross clamping?
  2. What are some common protective measures?
A
  • Spinal cord protection is essential
    • Cross clamp time greatly associated w/ paraplegia
      • <30 min = low risk
      • >60 min = up to 90% risk
  1. Crawford type 2 to have greatest risk of spinal/renal ischemia during cross-clamp
  2. Common Protective Measures
    1. Large bore access and central access
    2. Blood products and rapid transfuser
    3. Regional & Systemic Hypothermia
      1. protect SC and kidney during cross clamp by reducing metabolism
    4. Shunts and Bypass
    5. Spinal Drain
      1. Goal CSF pressure = 10 mmHg
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4
Q

At what point in pregnancy is maternal cardiac output the highest?

A

Immediatly following delivery

Up to 2.5x Pre-pregnancy values (150%)

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5
Q

Characteristics of teh following E-Cylinders

  • Physical State?
  • Cylinder Color?
  • Full Cylinder Capaicty in Liters?
  • Full Cylinder pressure psi?
  1. Oxygen
  2. Nitrous Oxyide
  3. Carbon Dioxide
  4. Air
  5. Helium
A
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6
Q

The difference between SIADH and Cerebral Salt Wasting Syndrome in Setting of CNS pathology

A
  • Both are common causes of Hyponatremia in patients w/ subarachnoid hemorrhage (10 - 34%).
  • SIADH
    • Increase ADH ►Renal water absorption►Plasma Sodium + Plasma Osmolarity LOW d/t EXCESS WATER PRESEN ► URINE SODIUM and OSMOLARITY HIGH d/t renal excretion
      • Patients Appear EUVOLEMIC or HYPERVOLEMIC d/t presence of excess water
    • TREAT WITH FREE WATER RESTRICTION
  • Cerebral Salt Wasting
    • ​Mechanism not well understood; inappropriate salt wasting ► Hyponatremia and low plasma osmolarity ► HIGH URINE SODIUM and HIGH URINE OSMOLARITY
    • PATIENTS APPEAR HYPOVOLEMIC
    • Treat with free water replacement and sodium administration
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7
Q

Arrow is Pointing at What Structure?

What is this view?

A
  • RIGHT VENTRICLE
  • Mid-Esophageal RV inflow-outflow
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8
Q

Transfusion of which blood product is most likely to cause transfusion associated sepsis?

A
  1. PLATELETS
    1. ​Stored at room temperature which increases risk of bacterial growth
    2. 3rd MCC of Transfusion related deaths
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9
Q

Chromosone 22q11 Deletion

  1. What is the disease?
  2. Characteristic Findings (“CATCH-22)
A
  1. Di George Syndrome​
  2. “CATCH-22”
    1. C = Cardiac Abnormalities
    2. A = Abnormal Facies
    3. T = Thymic Aplasia
    4. C = Cleft Palate
    5. H = Hypocalcemia
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10
Q

Identify the Block and Following Structures

Complications?

A
  • Interscalene Block
  • Horner’s Syndrome
  • Pneumothorax
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11
Q

What is a “3 in 1” Block

What Nerves Are Blocked?

A
  • A variation of femoral nerve block; 3 Nerves in 1 Injection
  • Provides greater anesthesia to thigh, helpful for more extensive proximal injuries
  • “FLO” through the 3 in 1
    • ​Femoral Nerve
    • Lateral Femoral Cutaneous Nerve
    • Obturator Nerve
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12
Q

Why do we use Mannitol during Kidney transplant surgery

A
  • Intaroperative mannitol administration prior to vessel clamp release during renal transplant is associated with decreased post-transplant kidney injury
  • Has NOT been shown to reduce graft rejection
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13
Q

True or False

Platelet Transfusions carry a lower risk of TRALI compared to PRBC transfusions

A
  • FALSE
  • Platelet transfusions carry a HIGHER risk of TRALI compared to PRBC transfusions
    • In fact they have a higher risk compared to PRBCs on all four of the following categories 1) TRALI 2) transfusion-associated sepsis 3) non-hemolytic febrile reactions and 4) allergic reactions.
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14
Q

Neonatal Resuscitation is based on what essential vital sign?

  1. What do you do if HR drops below 100 bmp
  2. If HR drops below 60 bpm
  3. If HR remains belowe 60 bpm
A
  • HEART RATE
  1. Initiate positive pressure venitlation
  2. CHEST COMPRESSIONS
  3. Epinephrine Administration
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15
Q

Definition of Time Constant as it relates to Anesthetic Circuit

A

Time constant = (volume or capacity of circuit)/Fresh Gas Flow (FGF)

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16
Q

Manifestations of Charcot-Marie Tooth Disease

Anesthetic Considerations

A
  • Neuropathy caused by mutations in myelin genes
  • Most common manifestations include distal extremity weakness and motor loss
  • Because of the demyelination that occurs in the distal extremities, monitoring the neuromuscular blockade should preferentially occur at the facial rather than the ulnar nerve.
  • Because of the concern for exacerbating the neurologic symptoms, however, regional anesthesia techniques are often avoided in these patients.
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17
Q

Most common cause of cardiac collapse in setting of venous air embolism?

A
  • Right Ventricular Air Lock Phenomenon
    • As air fills the right atrium and the right ventricle, it displaces blood and decreases blood flow into the right heart.
    • The blood flow in the right heart will become turbulent and lead to acute dilation of the right atrium and right ventricle.
    • A large enough volume of air will cause an air lock which prevents blood from exiting the right heart into the pulmonary circulation.
    • This is also known as right ventricular outflow tract (RVOT) obstruction and is the early cause of cardiovascular collapse.
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18
Q

Important drugs that do NOT cross the placenta

Hint: “He Is Going Nowhere Soon”

A
  • H = Heparin
  • I = Insulin
  • G = Glycopyrrolate
  • N = Non-depolarizing muscle relaxants
  • S = Succinylcholine
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19
Q

Purpose of dP/dt in assessment of cardiac function on echocardiography

A
  • dP/dt = rate of rise in ventricular pressure
    • Serves as a good measure of cardiac contractility
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20
Q

Spinal anesthesia onset of action and duration of action in infants compared to adults

A
  • Spinal anesthesia has MORE RAPID ONSET and SHORTER DURATION OF ACTION in infants compared to adults because
    • Higher cardiac output
    • Highly vascular pia mater
    • Loose myelination that provides little barrier to drug diffusion across the spinal cord.
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21
Q

The Liver receives greatest blood flow from which vessel?

What about oxygen delivery?

A
  • Portal vein = 75% of blood flow
    • Hepatic Artery = 25% of blood flow
    • Both vascular structures each deliver 50% of oxygen supply to liver
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22
Q

What is the role of the Hepatic Arterial Buffer Response (HABR)

What is the role of Adenosine?

A
  • Responsible for maintaining constant hepatic blood flow
    • Through HABR changes in portal venous flow induce reciprocal changes in hepatic arterial flow
    • ie. Hepatic arterial vasodilation in response to reduced portal venousflow.
  • Adenosine is KEY; produced in the periportal space of Mall (liver sinusoids) surrounding the local hepatic vasculature and diffuses into the portal vein.
    • ​As portal venous blood flow decreases ► adenosine accumulates in the hepatic vasculature. ► increased concentration of adenosine causes vasodilation of the hepatic artery and increased hepatic arterial blood flow.
    • As portal venous flow increases ► increased flow washes the adenosine out of the hepatic vascular system ►vasoconstriction of the hepatic artery.
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23
Q

What is the concern in the setting of acute discontinuation of TPN for a patient being taken for surgery?

A
  • HYPOGLYCEMIA
    • Hypoglycemia will occur because the significant carbohydrate load in TPN causes the pancreas to secrete excess insulin.
    • This elevated insulin level helps prevent hyperglycemia during infusion of TPN.
    • However, with acute discontinuation of TPN the pancreas continues to secrete insulin even after TPN has been stopped.
    • This period of time prior to the pancreas adjusting to a lower glucose load can cause a patient to experience significant hypoglycemia.
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24
Q

The “SHIVERS” of Serotonin Syndrome

A
  • S = Shivering
  • H = Hyperreflexia = myoclonus
  • I = Increased Temperature
  • V = Vital sign instability
  • E = Encephalopathy
  • R = Restlessness
  • S = Sweating
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25
Treatment of Hypermagnesemia in setting of Pre-Eclampsia
1. Stop infusion 2. Anatagonize affect of Mg w/ Caclium 3. Increase eleimination of Magnesium w/ loop diuretics and possibly dialysis
26
This CVP waveform is indicattive of which cardiac condition
* **Atrioventricular Dissociation** * Tall A wave, lacking C component ► **Cannon a wave** * **Atrium is contracting against a closed tricuspid valve**
27
What is happening at each point of this CVP waveform
* *a** – **atrial contraction** * *c** – tricuspid valve bulging into right atrium during **right ventricle isovolemic contraction** * *x** – tricuspid valve descends into right ventricle with ventricular ejection (atrial **relaxation**) * *v** – **venous return** to the right atrium * *y** – **atrial emptying** into right ventricle through open tricuspid valve
28
APGAR SCORE Category 0 Category 1 Category 2 What is the max score?
10
29
Nasal CPAP and the incidence of chronic lung disease in the pediatric population
* Nasal CPAP has **lowered the incidence of BPD** when compared to intubation and ventilation in neonates. * keeps small airways open, **decreases atelectasis, and maintains recruitment**
30
During an obturator nerve block, local anesthetic is depositved in which location?
1. Between the **adductor longus and adductor brevis muscles** (primary location) 1. In the thigh (at the level of the femoral crease) the **anterior branch travels between adductor longus and adductor brevis** 2. Carries **sensory fibers to the medial aspect of the thigh** 2. Between the **adductor brevis and adductor magnus muscles** 1. **​** The **posterior branch** travels between adductor brevis and adductor magnus. ​**​** 2. Blocking this branch will produce **significant motor weakness** which may interfere with exercises after a knee replacement surgery. mnemonic **ALABAM**a to remember superficial to deep: Adductor Longus, Adductor Brevis, Adductor Magnus.
31
Management of Sepsis According to the Surviving Sepsis Campaign Guidelines?
1. sepsis-induced hypoperfusion should be initially resuscitated with at least **30 mL/kg of intravenous crystalloid within the first three hours.** 2. If do not adequately respond to volume resuscitation initiate vasopressor therapy. An initial **MAP target of 65 mm Hg is recommended** and **norepinephrine is the preferred first-choice pressor.** 3. **Add Vasopressin to reduce levophed requirement**
32
Treatment of choice for management of surgical bleeding in patient with Type 1 vWD? If persistent bleeding despite initial treatment?
1. Desmopressin 2. Factor VIII-vWF 3. Cryoprecipitate 1. containts factors 8, 13, fibrinogen, fibronectin, **vWF**
33
Best regions to test sensation for L1 L2 L3 L4 L5 S1
34
Reflexes and Nerve root distribution association 1. Ankle Jerk 2. Knee Reflex 3. Biceps and brachioradialis 4. Triceps
**"One, two-- buckle my shoe. Three, four-- kick the door. Five, six-- pick up sticks. Seven, eight-- shut the gate."** ``` S1,2 = ankle jerk L3,4 = knee jerk C5,6 = biceps and brachioradialis C7,8 = triceps ```
35
Absolute indications for parenteral therapy When should it be started?
1. Short Gut Syndrome 2. Small Bowel Obstruction 3. Active GI bleeding 4. Pseudo-obstruction with complete intolerance to food 5. High output enterocutaneous fistula (\>500 mL/day) **Total parenteral nutrition (TPN) should not be started within the first 7 days of ICU admission. ​**
36
Complications of TPN
1. **INFECTION** 2. **Hyperglycemia from hyperosmolar infusion; hypoglycemia with acute discontinuation** 3. **Hypophosphatemia** 4. **Hypercarbia** 5. **Acute liver injury (increase PTT)** 1. **​TPN REQUIRES VITAMIN K SUPPLEMENTATION** **--Most Common---** 1. Hypomagnesemia 2. Hypokalemia 3. Hyperinsulinemia 4. Fluid Overload 5. Hepatic Steatosis (AST/ALT can rise) 6. Hyperchloremic metabolic acidosis **TPN should not be abruptly discontinued as it may result in hypoglycemia. For patients coming to the operating room on TPN, the infusion should typically be continued. If the infusion is stopped, glucose levels should be checked at least every hour.**
37
When would you need to **anesthethetize musculocutaneous nerve?** Between what muscles to do inject anesthetic
* As a supplement to an **Axillary nerve block to anesthetize lateral forearm** * Inject between the **Biceps and C****oracobrachialis muscle**
38
Treatment of patients with Hemophilia A and Factor 8 inhibition
**Prothrombin Complex Concentrate or Recombinant Factor VIIa**
39
Identify these Coagulation Disorders
1. Hemophilia 2. Von Wilebrand Disease 3. Disseminated Intravascular Coagulation 4. Vitamin K Deficiency
40
Treatment of Patients with Hemophilia B and Factor IX inihibition
**Recombinant Factor VIIa**
41
True or False: Nitrous Oxide has been shown to increase pulmonary vascular resistance
**TRUE** * Remember its **inhaled NITRIC Oxide (NO not N2O) that causes pulmonary vascular dilitation** * use **iNO** for management of **PULMONARY HTN.**
42
Doubling your distance from radiation sources decreases radiation exposure by how much?
1/4 Radiation exposure is inversely proportional to the square of the distance (1/radius^2). By doubling the radius from the source of radiation, the resultant incident radiation is 1/4th. Eight mrem per second divided by four is two mrem per second at the new distance.
43
When performing ENT procedures what is the advantage of using a microlarygnoscopy tube (MLT) compared to standard ETT?
* MLT tube is designed with **a smaller internal diameter** (4.0 - 6.0) to allow room for the surgeon * Compared to standard ETT MLT **tubes are longer** in order accommodate the adult airway, have **larger volume cuffs** with **LOW PRESSURES,** and are designed to be **less flexible.**
44
Acute vs Chronic respiratory acidosis; How does renal compensation occur and how does it affect HCO3 Levels
* Renal compensation for respiratory acidosis occurs at a slow rate * In **acute respiratory acidosis,** serum bicarbonate levels increase **1 mEq/L for each 10 mm Hg rise in PaCO2.** * If the **respiratory acidosis is chronic,** bicarbonate levels increase between **4-5 mEq/L for each 10 mm Hg rise in PaCO2.**
45
Destruction of motor neurons in the CNS is the mechanism of which virus?
* Polio Virus * Entero virus, fecal oral, infects cells in the spinal cord causing paralysis.
46
Inihibition of elongation factor 2 is the mechanism of which pathogen?
Corynebacterium diptheriae
47
Ribosylation of the inhibitory G protein recepter that inhibits the inhibitor of cAMP causing an increase in cAMP in the cell is the mechanism of which pathogen?
**Bordetella pertussis** "Whooping Cough"
48
Patient undergoes resection of parathyroid adenomas; one day later develops voice weakening after speaking for long period of time - most likely cause?
* **Injury to the external branch of the superior laryngeal nerve.** * Symptoms are subtle; **most prevalent symptoms is the patient's voice tires easily.**
49
Mechanism of Action of the Following Drugs - Should be FAST! 1. iNO 2. Nitroprusside 3. Nitroglycerin 4. Alprostadil 5. inhaled Epoprostenol 6. Isoproterenol 7. Epinephrine 8. Norepinephrine 9. Dobutamine 10. Sildenafil 11. Milrinone 12. Furosemide
50
Most common cause of hypotension in patients with LVAD
* Reduced SVR * Reduced Preload
51
Right to left cardiac shunt and its effect on Cardiac Output measurement using a thermistor
* In R to L Shunt injectate passes through the shunt and less volume goes into the Right Ventricle * **this leads to a false OVERESTIMATION of Cardiac Output** * Remeber as less injectate passes to the RV, the LESS time is allowed for temperature change between injection site and thermistor measurement * **LESS TEMPERATURE CHANGE = GREATER CARDIAC OUTPUT**
52
Transcutaneous pacing activates what part of the heart first?
* **Right Ventricle** * **​**Most anterior In the chest cavity * Followed by the Left Ventrile * **Transcutaneous pacing only allows pacing of ventricles**
53
Hemodynamic Goals in Hypertrophic Obstructive Cardiomyopathy
* Keep the LV full! * Maintain high pre load * Keep afterload up * Avoid tachycardia * Keep contractility down * First line therapy for Hypotension * IV crystalloids, albumin * Vasoconstrictors (phenylephrine) * **AVOID IONOTROPES AND VASODILATORS**
54
Criteria that may predict the need for postoperative mechanical ventilation in patients with **Myasthenia Gravis** ## Footnote **1.** **2.** **3.** **4.** **5.**
1. Duration of disease **6+ years** 2. Presence of **pulmonary disease(s) unrelated to MG (e.g., COPD)** 3. **Vital capacity of \< 2.9 L** (or \< 40 mL/kg) 4. **Negative inspiratory force (NIF) \< 20 cm H2O (e.g. 10 cm H2O)** 5. **Daily pyridostigmine dose \> 750 mg**
55
What is shown in this image? Etiology?
* **Tension Pneumocephalus** * **"Mount Fuji" Sign** * Occurs when **nitrous oxide is used after recent craniotomy (w/ in 2-3 weeks)** * Presents as delayed awakening, altered level of consciousness, convulsions, hypertension, bradiacardia. * Rx is **aspiration of air loculi by neurosurgeon**
56
Pickwickian Syndrome
* AKA Obesity Hypoventilation Syndrome * Hypoventilate at night and become hypercarbic and hypoxic
57
Difference between thyroid storm and malignant hyperthermia presentations
* MH has **muscle rigidity** TS does not * Rate of **EtCO2 rise in MH \> TS** * Temperature increase in MH \> TS * **Hyperkalemia, elevated CK, lactic acidosis** seen in MH not TS * Hypokalemia and elevated thyroid hormones seen in TS not MH
58
What is the preferred initial management of a bronchopleural fistula
Placement of Double Lumen tube
59
What is the most deleterious effect of neonatal hypothermia?
**Metabolic Acidosis** Results from **ketone production in brown fat** metabolsim (nonshivering thermogenesis)
60
True or False: Triple H therapy decreases the risk of morbidity and mortality from vasospasm
**FALSE** Studies have failed to show significant benefit from this and complications have occurred primarily as a result of hypervolemia.
61
Common Lab Changes in patients with ESRD 1. 2. 3. 4. 5. 6. 7. 8.
1. **- Hyperkalemia** 2. **- Hypermagnesemia** 3. **- Hyperphosphatemia** 4. **- Hypocalcemia** 5. **- Anemia** 6. **- Hyperlipidemia** 7. **- Hypertension** 8. **- Secondary Hyperparathyroidism**
62
Characteristics of Williams Syndrome
* Caused by deletion of Chromosome 7 * **"Elf like in appearence"** * May develop supravalvular aortic stenosis
63
Phantom limb pain is what type of pain? Pathophysiology?
**Neuropathic pain!** * Pain is **central in origin** and occurs due to misfiring spinal interneurons and maladaptive changes that occur within the sensory cortex after amputation
64
What is the Bezold Jarish Reflex?
Parasympathetic mediated reflex occurs when **stretch receptors located in the left ventricle respond to acute decrease in LV preload** ## Footnote **Results In bradycardia and reduced contractility ►Hypotension** **Occurs to allow ventricle additional time to fill and increase preload**
65
What are the 4 T's of the Heparin Induced Thromboycytopoenia score?
1. **Thrombocytopenia** 2. **Timing** of reduced platelet count 3. Presence of **thrombosis** 4. The exclusion of other causes of thrombocytopenia
66
Triggers for Hyperkalemic Periodic Paralysis
* **Autosomal dominant associated with MALIGNANT HYPERTHERMIA** * Potassium rich meals * Stress * **Rest after excercise** * Metabolic Acidosis * **Depolarizing Muscle Relaxant**
67
Key features on blood gas in Carbon Monoxide Poisioning
* Metabolic Acidosis * **NORMAL PaO2** * Falsely Elevated Calculated SaO2 and PaO2
68
Common Lab Findings Associated with Refeeding Syndrome
* Hypophosphatemia * Hyponatremia * Hypocalcemia * Hypomagnesemia * Hypokalemia * **Hyperglycemia**
69
What is shown in this image?
Tension Pneumothorax
70
Patient presents after motor vehicle accident, rib fractures and is hypotensive. Hemodynamic parameters show Heart rate: normal Cardiac output: normal Systemic vascular resistance: decreased Central venous pressure: decreased Pulmonary artery occlusion pressure: decreased **What type of shock is this?**
**Distributive Shock** * A spinal cord injury disrupting sympathetic outflow causing neurogenic shock is the most likely etiology. Due to this **lack of sympathetic outflow, the primary hemodynamic disturbance is a loss of systemic vascular resistance (SVR).** * Distributive shock is a **failure of the vasculature to generate adequate SVR**. Common causes of distributive shock are **septic shock, anaphylactic shock, and neurogenic shock.**
71
Idenify this view and what artery perfuses the arrow
Mid-papillary short-axis view
72
True or False: Children with Strabysmus are more likely to demonstrate masseter muscle rigidity after succinylcholine administration
TRUE * Children with strabismus are 4 times more likely to demonstrate masseter muscle rigidity (MMR) following succinylcholine administration for general anesthesia than children without strabismus.
73
What is the Bohr Effect
* Describes the decrease in amount of O2 bound to hemoglobin in setting in increasing CO2. * Right shift in oxygen dissociation curve causes by changes in concentration of CO2 and pH
74
Patients w/ lumbar spinal stenosis are exascerbated by what moves
* Spinal stenosis causes **pain in a radicular pattern and also causes neurogenic claudication.** Pain is caused by **mechanical compression of the nerve roots.** Spinal stenosis is often caused by spondylosis and degenerative arthritic changes of the spine. * Pain is exascerbated by extension of spine - ie. walking DOWNHILL * Pain alleviated with FLEXION of spine - ie. walking up hill, squatting
75
Smoking cessation and timeline of Pulmonary Changes 12 hours 2 - 4 weeks 6 - 8 weeks
76
What part of the spinal cord is most directly affected by spinal cord stimulation?
**Dorsal horn of the spinal cord** ## Footnote The Aα and Aβ sensory nerve fibers largely conduct innocuous stimuli, whereas nociceptive stimuli are mainly transmitted by smaller diameter, thinly myelinated, or unmyelinated Aδ and C fibers. In 1965, Melzack and Wall proposed the **“gate theory”** of pain. An abundance of small afferent activity allowed the transmission of nociception through the substantia gelatinosa of the dorsal horn in the spinal cord. **A spinal cord stimulator provides electrical stimulation to larger fibers, which have a lower threshold for recruitment by external electrical stimulation, and thereby closes the “gate” of the dorsal column.** The closed “gate” prohibits transmission of the smaller, slower conducting fibers associated with chronic pain sensation. In other words, **by triggering larger, faster transmitting Aα (conduction velocity 80-120 m/s) and Aβ fibers (30-70 m/s) within the same distribution as the slower Aδ (5-25 m/s) and C fibers (0.6-2 m/s) that are transmitting pain, a spinal cord stimulator effectively closes the “gate” in the dorsal horn, thereby reducing nociception.**

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