Board Prep Flashcards
(158 cards)
1
Q
Decreased ETCO2
A
Hypothermia Hypothyroidism Increased Dead Space (COPD) Hyperventilation Decreased Cardiac Output Decreased CO2 production Circuit leak or Occlusion Pulmonary Embolism (air, thrombus, gas, fat, marrow, amniotic) Increased muscle relaxation Increased depth of anesthesia Surgical manipulation of the heart or thoracic vessels Wedging of the PA Catheter
2
Q
Increased ETCO2
A
Increased CO2 production (MH, thyrotoxicosis, hyperthyroidism) Hyperthermia Shivering or convulsions Sepsis Rebreathing (valve prolapse, failed CO2 absorber) Hypoventilation Depression of the respiratory center Reduction of ventilation Increased or improving Cardiac Output Right to left intracardiac shunt Excessive catecholamine production Administration of blood or bicarbonate Release of aortic clamp/arterial clamp or tourniquet Glucose in the IV fluid Parenteral hyperalimentation CO2 insufflation Subcutaneous epinephrine injection
3
Q
Minimal to zero ETCO2 or Sudden Drop
A
Equipment Malfunction ETT disconnect, obstruction, or total occlusion Bronchospasm No Cardiac Output Cardiac Arrest Bilateral PTX Massive PE Esophageal intubation Application of PEEP Cricoid pressure occluding tip of ETT Sudden, severe hypotension
4
Q
Determining source of decreased ETCO2
A
Call for help
Assess vital signs
Feel for a pulse
Take patient off ventilator and handbag listening for breath sounds
5
Q
EKG interpretation
A
Rhythm Regularity P wave (2.5 mm long and high) (Best viewed in Lead II) PR interval (No longer than 0.2 seconds) Q wave QRS complex (up to 0.12 seconds) (R & R prime in V1 = RBBB, R & R prime in V6 = LBBB) ST segment (V5 most sensitive lead) T wave Axis
6
Q
ASA recommendations for preoperative EKG
A
Age >50 yo (good for one year if 50-69, good for 6 months if >69)
History of cardiovascular disease or HTN (mandatory if changes in symptoms)
History of DM (required if >40 yo or has had DM >10 years)
Central nervous system disease
7
Q
Standard ASA Monitors
A
Oxygenation (pulse ox)
Ventilation (ETCO2, respiratory volumes, disconnect alarms)
Circulation (EKG, blood pressure, HR - every 5 minutes)
Temperature
8
Q
Indications for arterial line
A
Continuous real time blood pressure monitoring
Planned pharmacological or mechanical cardiovascular manipulation
Repeated blood sampling (ABG, Hgb, Glucose)
Failure of indirect BP measurement
Supplementary diagnostic information from the arterial waveform (PPV)
Patient with end organ disease
Patient with large fluid shifts
9
Q
Arterial line complications
A
Distal ischemia (thrombosis, proximal emboli) Pseudoaneurysm AV fistula Hemorrhage Hematoma Infection Skin necrosis Peripheral neuropathy Misinterpretation of data Cerebral air embolism from retrograde flow from flushing
10
Q
Indications for central line
A
CVP monitoring Transvenous cardiac pacing Pulmonary Artery Catheter Temporary hemodialysis Drug administration (vasoactive, hyperalimentation, chemotherapy, prolonged antibx) Rapid infusion of fluids Major surgery with large fluid shifts Aspiration of a venous air embolus Inadequate peripheral access Sampling site for repeated blood testing
11
Q
PA Catheter measurements
A
Cardiac Output and Index (CO/CI) Pulmonary Artery Pressure (PAP) Central Venous Pressure (CVP) Calculation of oxygen delivery Assessment of cardiac work Mixed Venous Oxygen Saturation (MVO2) Pulmonary Capillary Wedge Pressure (PCWP) Systemic Vascular Resistance (SVR)
12
Q
Indications for PA Catheter
A
Cardiac (CHF, low EF, left sided valvular dz, CABG, aortic cross clamp)
Pulmonary (COPD, ARDS)
Complex fluid management (shock, burns, acute renal failure)
High risk obstetrical care (eclampsia, placental abruption)
Neurological (sitting craniotomy, venous air embolus)
13
Q
Causes of Hypernatremia
A
Inadequate intake of fluid
Renal loss of hypotonic fluid (diuretics, DI, intrinsic renal disease)
Extrarenal (nonrenal loss of H20)
Primary Na gain (hypertonic tube feeds or fluids)
14
Q
Clinical features of Hypernatremia
A
Altered mental status Lethargy Confusion Coma Seizures Pleural effusion Ascites Peripheral edema Heart Failure Thirst Nausea and Vomiting Neuromuscular irritability
15
Q
Treatment of Hypernatremia
A
Determine volume status (diuresis if hypervolemic) (Free H2O deficit = {(plasma Na/140)-1} x kg x 0.6, replace half of water deficit in first 24 hours, then remainder over 2-3 days, use 5% dextrose in water or 0.45% NaCl)
Rate of Na correction should not exceed 0.5 mEq/L per hour
16
Q
Treatment of Central Diabetes Insipidus
A
DDAVP (IV 2-4 mcg)(Nasal Spray 10-40 mcg)
Low Na Diet
Low dose thiazide diuretic
Carbamazepine (enhances vasopressin secretion)
NSAIDs
17
Q
Treatment of Nephrogenic Diabetes Insipidus
A
Treat underlying cause
Treat symptomatic polyuria (Low Na diet, thiazide diuretic)
18
Q
Causes of hypovolemic hyponatremia
A
Non renal (GI losses, integumentary losses, third spacing, cerebral salt wasting)
Renal (Diuretics, osmotic diuresis, hypoaldosteronism, salt wasting nephropathy, post obstructive diuresis, non-oliguric acute tubular necrosis, acute and chronic renal failure)
19
Q
Causes of euvolemic hyponatremia
A
Polydipsia (psychogenic, exercise induced, medications)
Administration of hypotonic IV fluids
Beer potomania
SIADH (neurologic, pulmonary disease, malignant tumors, major surgery, pharmacologic)
20
Q
Causes of hypervolemic hyponatremia
A
Renal (acute or chronic failure) Non renal (heart failure, hepatic cirrhosis, nephrotic syndrome) Redistributive hyponatremia (hyperglycemia, mannitol) Pseudohyponatremia (hyperlipidemia, hyperproteinemia, glycine solutions) Endocrine disorders (adrenal insufficiency, hypothyroidism)
21
Q
Causes of hyperkalemia
A
Pseudohyperkalemia (hemolysis, prolonged use of tourniquet, marked leukocytosis)
Endogenous K (tumor lysis, rhabdomyolysis, exercise induced, burns)
Exogenous K (increased intake, transfusions)
Renal (insufficiency, chronic failure, oliguria, nephropathy)
Acidosis (metabolic raises K 0.7/0.1 pH, resp raises K 0.1/0.1 pH, diabetic ketoacidosis)
Drugs (succinylcholine, Beta blocker, digitalis, ACEI, heparin, cyclosporine,
spironolactone, amiloride, triamterene)
Endocrine (primary adrenal insufficiency, pseudohypoaldosteronism)
Hyperkalemic periodic paralysis (excitement, cold, fasting, stress, infection, GA)
Chronic hyperkalemia (decreased renal excretion)
22
Q
Clinical features of hyperkalemia
A
Weakness, tingling, parathesias
Flaccid paralysis
Hypoventilation
Cardiac toxicity (increased T waves, flattened P wave, AV conduction delay, QRS
widening, v fib/flutter)
23
Q
Treatment of hyperkalemia
A
Non emergent (reduce K intake, increase K output, IV loop and thiazide diuretics,
consider dialysis)
Emergent (calcium chloride centrally or calcium gluconate peripherally, sodium bicarb,
D50 plus insulin, albuterol)
24
Q
Causes of hypokalemia
A
Redistribution of K into cells
Metabolic alkalosis (decrease K 0.3/0.1 pH)
Medications (insulin, epi and selective beta2 agonists)
Hypokalemic periodic paralysis
Potassium depletion
Decreased dietary intake
Extra renal (diarrhea, laxatives, intestinal bypass or fistula, vomiting and gastric suction)
Renal (diuretics, steroids, PCN derivatives, renal tubular acidosis, diabetic keto,
mineralocorticoid excess - hyperaldosteronism)
25
Clinical features of hypokalemia
Non cardiac (fatigue, myalgia, weakness, constipation, polydipsia and polyuria,
hypoventilation, paralysis)
Cardiac (arrhythmias, a fib, PVCs, flattening T waves, prominent U waves, ST depression,
prolonged QT, prolonged PR, widening QRS)
26
Treatment of hypokalemia
Correct underlying disorder
Asymptomatic or minor (oral K, encourage K rich diet)
Cardiac manifestations or severe (IV K ideally through central access)
Address possible hypomagnesemia
27
Causes of hypocalcemia
```
Parathyroid hormone deficiency
Vitamin D deficiency
Hyperphosphatemia (renal failure, tumor lysis, rhabdomyolysis)
Renal failure
Citrate toxicity
Acute alkalemia
Post cardiopulmonary bypass
Acute pancreatitis
```
28
Clinical features of hypocalcemia
Cardiovascular (dysrrhythmias, QT prolongation, heart failure, hypotension, impaired beta
adrenergic action)
Neuromuscular (tetany, muscle spasm, papilledema, seizure, weakness, fatigue,
paresthesias, irritability, mental status changes)
Respiratory (apnea, laryngeal spasm, bronchospasm)
Psychiatric (anxiety, dementia, depression, psychosis)
29
Treatment of hypocalcemia
```
IV calcium
Magnesium
Correct metabolic and/or respiratory alkalosis
Oral calcium or oral vitamin D
Avoid hyperventilation
Avoid bicarbonate
```
30
Causes of hypercalcemia
```
Malignancy (vast majority)
Hyperparathyroidism
Vitamin D intoxication
Sarcoidosis
Hyperthyroidism
Immobilization
Thiazide diuretics and lithium
```
31
Clinical features of hypercalcemia
Lethargy
Anorexia
Nausea
Polyuria
Neuromuscular (weakness, depression, impaired memory, emotional lability, lethargy,
stupor, coma)
Cardiovascular (hypertension, dysrhythmias, widening QRS, short QT, heart block, arrest)
32
Propofol infusion syndrome
```
More common in critically ill children
Cardiomyopathy
Rhabdomyolysis
Severe metabolic acidosis
Hyperkalemia
Hepatomegaly
Lipemia
Renal Failure
```
33
Hypoxemia (pathophysiologic mechanism)
Decreased inspired oxygen (failure of anesthesia machine, disconnection, gas pressure
failure, crossing of tanks, etc)
Hypoventilation (esophageal intubation, ETT kinking, blockage, herniated or ruptured
cuff, right main stem intubation, respiratory depression)
Impaired diffusion
VQ mismatch
Right to left shunt (PFO, TOF)
Intrapulmonary derangements
34
Hypoxemia (structural anatomic)
Alveoli (pulmonary edema, acute lung injury, ARDS, pulmonary hemorrhage, PNA)
Interstitium (pulmonary fibrosis, viral PNA, allergic alveolitis)
Heart and pulmonary vasculature (PE, intracardiac or intrapulm shunt, CHF)
Airways (asthma, COPD, mucus plugging, right main stem intubation)
Pleura (PTX, pleural effusion)
35
Intraoperative Acute Hypoxia
Check color of patient
Check for a pulse
Check vital signs
Check for ETCO2
Take off ventilator and hand bag with 100% FIO2
Call for help
Check O2 monitor, peak airway pressure, and capnograph waveform
Listen to chest for bilateral breath sounds and chest rise
Evaluate ETT
Listen for wheezing
Bronchospasm - deepen anesthetic with volatile or give epi
Chest xray
36
Tension PTX
```
Presentation
Unilateral absence of breath sounds
Tracheal deviation
Unexplainable hypotension
Distended neck veins
Treatment
Find 2nd intercostal space
Find midclavicular line
Insert 14 gauge angiocath over top of the rib
Listen for decompressive air rush
Leave angiocath in place
Place chest tube
```
37
Causes of hypercarbia
```
Increased production of CO2
Tourniquet release
Aortic cross clamp release
MH
Sepsis
Thyrotoxicosis
Fever
Decreased removal of CO2
Hypoventilation
Airway Obstruction
Increased Dead Space
Rebreathing of CO2 due to mechanical malfunction
Iatrogenic
Sodium Bicarb administration
Increased CO2 during laparoscopic procedure
```
38
Indications for Intubation
```
Mechanical Function
Respiratory Rate >35
Vital capacity <15 ml/kg adult
Vital capacity <10 ml/kg child
Negative inspiratory force less than 20-25 cm H2O
Gas Exchange Function
PaO2 <60 on FiO2 of 50%
A-a gradient >350 on FiO2 of 100%
PaCO2 >55
Dead Space Ventilation/Tidal Volume (Vd/Vt) ration >0.6
Unstable Vital Signs
Inability to protect airway
```
39
Indications for Extubation (subjective)
```
Subjective
Resolution of acute disease
Adequate cough
Awake, alert, following commands
Cooperative
GCS >13
No sedation
Sustained hand grip
Sustained head lift >5 seconds
Able to tolerate spontaneous ventilation
Acceptable electrolytes
Able to protect airway
Clear oropharynx
Adequate pain control
Minimal end expiratory concentration of inhaled anesthetics
```
40
Indications for Extubation (objective)
```
Objective
Vital Signs
RR <30-35
Stable BP
HR <140
Afebrile
Gas Exchange
PaO2 >60
PaCO2 <55
PaO2/FiO2 >150-300
Alveolar arterial PaO2 gradient <350 on 100% oxygen
Maintenance of normal pH
Mechanical
FVC >10-15 ml/kg
FEV1 >10 ml/kg
TV >4-6 ml/kg
Negative Inspiratory Force >20
VC >15 ml/kg
Dead Space ventilation/Tidal Volume (Vd/Vt) <0.6
Rapid Shallow Breathing Index (RSBI) (f/Vt) <60-100 breaths/min
Adequate hemoglobin
No significant respiratory acidosis
```
41
Difficult Airway Algorithm
Look up Diagram
42
Pathological States that Predispose to Difficult Intubations
Congenital
Pierre-Robin (micrognathia, macroglossia, cleft palate)
Treacher-Collins (mandibular hypoplasia)
Down's (macroglossia, atlantoaxial instability)
Kippel-Feil (restricted neck movement secondary to cervical vertebrae fusion)
Infection
Croup
Ludwigs angina
Abscess
Arthritis
Rheumatoid
Ankylosing spondylitis
Benign tumors
Malignancy
Injury (facial, cervical, laryngeal, tracheal, burns)
Diabetes
Scleroderma
Obesity
Pregnancy
Acromegaly
Anatomic abnormalities (micrognathia, limited jaw motion)
43
Criteria to Predict Difficult Airway
History (previous difficult, burns, edema, bleeding, airway stenosis, GERD, poor dentition,
radiation treatments)
Physical
General (obesity, cervical collar, traction device, external trauma, respiratory difficulty)
Patency of nares
Mouth opening (less than two finger breadths)
Teeth (prominent incisors, overbite, loose teeth)
Palate (high, narrow mouth)
Tongue
Prognathism
Thyromental distance <6cm
Neck (short and thick, limited extension, limited flexion)
Specific tests
Mallampati score of 3 or higher
Laryngoscopic grades III or IV
Radiographic assessments
Diabetic predictors (positive prayer sign - gap between palms)
44
Pediatric Airway - Differences
Larger occiput
Hypertrophied tonsil and adenoid tissue
More cephalad larynx (C2-3 premature, C3-4 infant, C4-5 adult)
More narrow and shorter epiglottis, angled into airway
Tongue larger in proportion to oral cavity
Cricoid cartilage is narrowest area (vocal cords in adult)
Obligate nasal breathers
45
Pediatric ETT selection
Uncuffed: Internal diameter (mm) = (16+age)/4
46
Pediatric Physiology - Pulmonary
Prone to peri-operative hypoxemia
High closing volumes
High MV/FRC ratio
Leads to rapid uptake of volatile
Faster inhalational induction (also greater cardiac output per kg)
Lower blood gas partition coefficient
Pliable rib cage
Diaphragm primary contributor to ventilation
If increased O2 demand
Increases RR
Increase respiratory excursion by diaphragmatic contraction
Leads to negative intra-thoracic pressure and retractions
Inefficient form of ventilation with high energy expense
47
Pediatric fluid maintenance and fluid deficit
Maintenance
4 ml/kg/hr for 1st 10 kg
2 ml/kg/hr for 2nd 10 kg
1 ml/kg/hr for each remaining kg
Deficit
Estimated = estimated hourly maintenance x number of hours NPO
48
Estimated Blood Volume
```
Premature 90 ml/kg
Full term 85 ml/kg
Infant 80 ml/kg
Child 75 ml/kg
Adult 70 (male) and 65 (female) ml/kg
```
49
NPO guidelines
```
Clear liquids: 2 hours
Breast milk: 4 hours
Formula: 6 hours
Nonhuman milk: 6 hours
Meal with fat: 8 hours
```
50
Risk Factors for Fetal Distress
```
Maternal
Diabetes
Pregnancy induced hypertension
Previous stillbirth
Infection
Substance abuse
C-section
General anesthesia
Chronic HTN
Previous Rh sensitization
Bleeding in 2nd or 3rd trimester
Fetal
Post term or preterm
Poly or oligohydramnios
Known fetal anomalies
Abnormal fetal lie
Non reassuring FHT
Meconium stained amniotic fluid
```
51
Dyspnea - Differential Diagnosis
Obstruction to flow (asthma, emphysema, bronchitis, stenosis, malacia)
Resistance to lung expansion (fibrosis, restrictive disease
Resistance to chest expansion (pleural thickening, kyphoscoliosis, obesity, mass)
Weakness of pump (polio, neuromuscular disease)
PTX
Increased respiratory drive (hypoxemia, metabolic acidosis)
Psychological (anxiety, depression)
52
Dyspnea - Treatment Plan
```
Reduce the sense of effort
Improve muscle function
Decrease respiratory drive
Alter CNS function
Exercise training and pulmonary rehab
```
53
Tachypnea - Causes
Airway obstruction (extra or intra thoracic)
Anxiety/pain
Acute circulatory failure (CHF, cardiomyopathy)
Intrapulmonary (COPD, restrictive disease, asthma, aspiration, atelectasis, edema, PTX,
PE, pHTN)
Disease of chest wall or musculature (polio, MG)
Systemic Disease (sepsis, acidosis, hypoxia, shock, fever, MH, infection,
hypophosphatemia)
Excessive post exercise oxygen consumption
Hypermetabolic state
Hyperthyroidism
54
Wheezing - Differential Diagnosis
```
Bronchospasm
Asthma
COPD
Tracheobronchitis
Restrictive Pulmonary Disease
RA associated bronchiolitis
Extrinsic compression
Intrinsic compression
CHF
PE
Mechanical obstruction of ETT
Inadequate depth of anesthesia
Endobronchial intubation
Pulmonary aspiration and edema
PTX
```
55
Bronchospasm - Differential Diagnosis
```
Kinked ETT
Solidified secretion or blood
Pulmonary Edema
Tension PTX
Aspiration Pneumonitis
PE
Endobronchial intubation
Persistent cough or strain
Negative Pressure Expiration
```
56
Bronchospasm - Intraoperative Treatment
```
100% oxygen
Deepen anesthetic
Albuterol
IV or SQ epinephrine
Consider IV magnesium
```
57
Laryngospasm complications
Hypoxia
Noncardiogenic pulmonary edema
Cardiac arrest
58
Laryngospasm treatment plan
```
100% oxygen
Remove irritating factor
Jaw thrust
Positive pressure ventilation
Increase depth of anesthesia
IV or topical lidocaine
Call for help
Succinylcholine (10-50 mg IV, IM, or SL)
Attempt intubation
```
59
Stridor differential diagnosis
Inspiratory: upper airway obstruction
Expiratory: lower airway obstruction
Biphasic: mid tracheal lesion
60
Stridor treatment plan
```
Evaluate
Rule out need for emergent intubation
History
Physical exam
Chest Xray
ABG
Flexible bronchoscopy
Consider ENT consult
Oxygen - facemask
Head up position
Nebulized racemic epinephrine
IV Dexamethasone (4-8 mg every 8-12 hours)
Heliox
```
61
OSA - AHI index (Apena-hypoapnea)
Average number of apneas and hypoapneas per hour
Mild OSA: AHI 5-15
Moderate OSA: AHI 16-30
Severe OSA: AHI >30
62
OSA - Peri operative concerns
```
Increased risk for difficult intubation
Post-operative hypoxemia
Post-operative airway obstruction
Myocardial Ischemia
Arrhythmia
Death
```
63
One Lung Ventilation - Indications
Absolute
Isolation to prevent spillage (infection, hemorrhage)
Control of ventilation (bronchopleural fistula, surgical opening of conducting airway,
cyst, tracheobronchial tree disruption, life threatening hypoxemia from unilateral
airway disease)
Unilateral bronchopulmonary lavage
Relative
Surgical exposure (thoracic aortic aneurysm, pneumonectomy, upper lobectomy,
mediastinal exposure, thoracoscopy, middle and lower lobectomies, esophageal
resection, thoracic spine surgery)
Severe hypoxemia from unilateral lung disease
64
One Lung Ventilation - Treatment of Hypoxia
Increase FIO2 to 100%
If severe, switch to two lung ventilation
Check position of DLT
Apply CPAP (5-10 cm H20) to nondependent lung
Apply PEEP to dependent lung
Intermittently ventilate both lungs
In emergency, have surgeon clamp pulmonary artery
65
Hypotension - Differential Diagnosis
Pulmonary: hypoxia, hypercarbia, tension PTX
Hypovolemia: fluid deficit, acute blood loss
Cardiac: rate/rhythm, inotropic failure, myocardial ischemia, contusion, tamponade,
rupture, CHF, cardiomyopathy, valvular injury, lesion
Shock: hypovolemia, cardiogenic, septic
Surgical compression of the heart, aorta, IVC, or abdominal contents
Embolus: pulmonary, air, fat, amniotic
Electrolyte and hormonal abnormalities: hypoglycemia, hypocalcemia, adrenal
insufficiency, ADH suppression, hypermagnesemia
Anaphylaxis
Deep anesthesia, drug overdose, medications
Hypothermia
Sympathetic block, neuraxial block
Venodilation
Laparoscopic surgery: hypercarbia, dysrhythmia, increased vagal tone from peritoneal stretch, compression of IVC, venous gas embolism
66
Hypotension - Preoperative treatment plan
```
Recheck and validate
Evaluate - symptoms
Physical exam - auscultate, palpate pulses, mucus membranes, temperature, bleeding
Supplemental Oxygen
Increase IV fluids
Review history
Review medications
Determine baseline BP
Consider EKG
ABG, electrolytes, chest Xray
Treat
Consider postponement of elective surgery unless can be treated surgically
```
67
Hypotension - Intraoperative treatment plan
```
Confirm BP
Evaluate ABCs, vitals, temp, ETCO2
Place on 100% oxygen
Decrease volatile if tolerated
Increase IV fluids
Evaluate surgical field (bleeding, IVC compression)
Review history and physical exam
Consider invasive hemodynamic monitors and TEE
Stop vasodilating infusions
Start inotropic therapy
Phenylephrine
Ephedrine
Epinephrine
Norepinephrine
Dopamine
Dobutamine
Milrinone
Place in Trendelenburg
```
68
Hypertension - Differential Diagnosis
Pre-existing HTN
White coat HTN
Pulmonary: hypoxia, hypercarbia, pulmonary edema, OSA
Renal: renovascular disease, renal parenchymal disease, renin-secreting tumor,
polycystic kidney disease
Neurologic: elevated ICP, spinal cord injury, Guillan-Barre syndrome, dysautonomia
Cardiac: ischemia, stiff vessels, aortic coarctation, fluid overload
Endocrine: Cushing's, pheochromocytoma, thyrotoxicosis, hyperaldosteronism,
hyperparathyroidism
Vascular: coarctation of the aorta, vasculitis, collagen vascular disease
Drugs: vasopressors, cocaine, MOAI inhibitors, TCAs, naloxone, glucocorticoids,
mineralocorticoids, OCPs, withdrawal
Pain, anxiety, inadequate anesthesia
Malignant hyperthermia
Hypothermia
Electrolyte abnormalities: hypercalcemia, hypoglycemia
Autonomic instability
69
Hypertension - Preoperative treatment plan
Confirm BP
Evaluate patient (ABCs)
Review history and pharmacology
Postpone elective case if signs of target organ damage
70
Hypertension - Intraoperative treatment plan
```
Confirm BP
Evaluate ABCs, vitals, ETCO2
Verify oxygenation and ventilation
Consider 100% O2
Review history and physical
Consider placement of invasive monitors
Anti-hypertensive agents
Beta blockers
Alpha receptor blockers (hydralazine)
Alpha receptor agonist (clonidine, dexmedetomidine)
Vasodilators (nitroglycerin, sodium nitroprusside)
Monitor for myocardial ischemia
```
71
Arrhythmia - intraoperative causes
General anesthetics
Local anesthetics (sympathectomy)
Abnormal ABG and electrolytes (ph, hypoxia, hypercarbia)
Sympathetic response to intubation
Reflexes: Vagal (brady, AV block, asystole), Carotid sinus stimulation (brady),
Oculocardiac (brady or asystole)
CNS stimulation
Autonomic nervous system dysfunction
Pre-existing cardiac disease: MI, CHF, Cardiomyopathy, Valvular dz, Conduction
abnormalities
Central Venous Cannulation
Surgical manipulation (atrial, venous bypass cannulas)
Location of surgery: dental, trigeminal)
Pain
Hypovolemia
Hypotension
Anemia
Endocrine abnormalities: hyperthyroidism, pheochromocytoma
Temperature abnormalities
72
Arrhythmia - assessment
```
Best evaluated in Lead II
Rate?
Regular?
One P wave for each QRS?
QRS normal?
Rhythm dangerous?
Hemodynamic disturbance?
Is treatment required?
How urgently does it need to be treated?
```
73
Asystole and PEA - Causes
```
Hypovolemia
Hypoxia
Acidosis
Hyper and hypokalemia
Hypoglycemia
Hypothermia
Toxins/Tablets
Tamponade
Tension Pneumothorax
Thrombosis
Trauma
```
74
Asystole and PEA - Treatment
Call for help
CPR
Oxygen
Attach monitor/defibrillator
Epinephrine 1 mg IV/IO, repeat every 3-5 minutes
Atropine 1 mg IV/IO, repeat every 3-5 minutes
Look for and treat underlying causes
75
Sinus Bradycardia - Causes
```
Hypoxia/hypercarbia
Drug effects: beta blockers, opioids, succinylcholine, anticholinesterase inhibitors,
anesthetics
Acute inferior MI
Vagal stimulation: oculocardiac, visceral
High sympathetic blockade
Acidosis
Allergic reaction
Hypertension
Increased ICP: Cushing's
Baseline bradycardia
```
76
Sinus Bradycardia - Treatment
Check all vital signs
Check baseline HR
Ensure secure airway with adequate oxygenation and ventilation
Obtain 12 lead EKG
Treatment if hypotension, ventricular, or signs of poor perfusion
Atropine 0.5-1 mg IV/IO, may repeat every 3-5 minutes up to 0.04 mg/kg
Ephedrine 5-10 mg IV
Isoproterenol 2-10 mcg/minute IV infusion
Temporary transcutaneous or transvenous pacing
77
Sinus Tachycardia - Causes
```
Hypoxia/hypercarbia
Pain/anxiety
Inadequate anesthesia
Fever/MH/Sepsis
CHF
Drug effect: catecholamines, pancuronium, anticholinergics, vasodilators
Endocrine: hyperthyroidism, thyrotoxicosis, pheochromocytoma
Electrolyte: hypoglycemia
Surgery
PE
Pacemaker malfunction
Drug withdrawal
Bladder distension
```
78
Sinus Tachycardia - Treatment
```
Stable
Check vital signs
Check EKG
Check baseline HR
Check oxygenation and ventilation
Treat underlying disorder
Consider beta blockers
Unstable with a pulse
Support airway, breathing, circulation
Oxygen
Check vital signs
IV access
Synchronized cardioversion: 100, 200, 300, then 360 joules
```
79
Paroxysmal Supraventricular Tachycardia (PSVT) - Etiology
```
Intrinsic heart disease
Systemic illness
Thyrotoxicosis
Digitalis toxicity
Pulmonary embolism
Pregnancy
Changes in autonomic nervous system
Drug effect
Intravascular volume shifts
```
80
Paroxysmal Supraventricular Tachycardia (PSVT) - Treatment
Vagal maneuvers
Adenosine 6 mg (may be repeated)
Verapamil 2.5-10 mg IV
Amiodarone 150 mg IV over 10 minutes
Esmolol 1 mg/kg bolus and 50-200 mg/kg/min infusion
Edrophonium 5-10 mg
Phenylephrine IV if hypotensive
Digoxin 0.5-1.0 mg
Rapid overt pacing in attempt to capture ectopic focus
Synchronized cardioversion: 50, 100, 200, 300, and 360 joules
81
Atrial Flutter/Fibrillation - Causes
```
Severe heart disease
Coronary artery disease
Mitral valve disease
Pulmonary embolism
Hyperthyroidism
Cardiac trauma
Cancers of the heart
Myocarditis
```
82
Atrial Flutter - Treatment
Stable
Rule out thrombotic event
Synchronized cardioversion
Pharmacologic cardioversion
Control ventricular rate by slowing conduction through AV node
Beta blockers: esmolol, propranolol
Calcium Channel blockers: verapamil, diltiazem
Unstable
Start synchronized DC cardioversion: 100 joules, gradually increasing to 360 joules
Procainamide 5-10 mg/kg loading dose with a 0.5 mg/kg/minute infusion
Rapid atrial pacing from within atrium
83
Atrial Fibrillation - Treatment
Acute
IV Diltiazem or esmolol
Synchronized cardioversion: 100-200 joules, then 300, then 360
If present >48 hours, consider TEE to rule out thrombus
Long-term therapy
Coumadin
Beta blockers, calcium channel blockers, digitalis (all for HR control)
Electrode catheter ablation of AV junction and permanent pacer placement
Implanted atrial defibrillator
Prevention of Recurrence: quinidine, flecainide, sotalol, amiodarone, dofetilide
84
Ventricular Tachycardia - Treatment
Amiodarone 150 mg IV over 10 minutes
| Synchronized cardioversion: 100-200 joules, then 300, then 360
85
Ventricular Fibrillation
```
Causes
Myocardial Ischemia
Hypoxia
Hypothermia
Electric shock
Electrolyte imbalance
Drug effect
Treatment
CPR
Oxygen
Monitors/Defibrillator
Asynchronized Cardioversion: 120-200 joules biphasic, 360 joules monophasic)
Epinephrine 1 mg every 3-5 minutes
Consider Amiodarone (300 mg followed by 150 mg), Lidocaine (1-1.5 mg/kg, then 0.5-
0.75 mg/kg), Magnesium (1-2 grams for torsades)
```
86
Cardiac Ischemia - Lead changes and associated artery
```
V1-V2
Left Coronary (LAD)
Septum, AV bundle, bundle branches
V3-V4
Left Coronary (LAD and diagonal)
Anterior wall of LV
V5-V6 plus I and aVL
Left Coronary (Circumflex)
High lateral wall LV
II, III, aVF
Right Coronary (Posterior Descending)
Inferior wall LV and posterior wall LV
V4R
Right Coronary (proximal branches)
RV, inferior wall LV, posterior wall LV
V1-V4 (marked depression)
Left Coronary (circumflex) or Right Coronary (posterior descending)
Posterior wall LV
```
87
Cardiac Tamponade - Induction
Ketamine first line agent (etomidate second choice)
Neuromuscular blocker
No Midaz (systemic vasodilation)
Avoid Narcotics (bradycardia)
Reduce inspiratory positive pressure (to allow for cardiac filling)
88
Cardiac Evaluation - Major clinical risk predictors
```
Unstable Coronary Syndromes
Unstable or severe angina
Recent MI
Significant Arrhythmia
Severe valvular disease
Decompensated Heart Failure
```
89
Cardiac Evaluation - Revised Clinical Risk Predictors (stable conditions)
Ischemic Heart Disease: history of MI, history of positive treadmill test, use of
nitroglycerine, current complaints of chest pain, EKG with abnormal Q waves
Congestive Heart Failure: history of heart failure, pulmonary edema, paroxysmal
nocturnal dyspnea, peripheral edema, bilateral rales, S3 heart sound
Cerebral Vascular Disease: history of TIA, history of stroke
Preoperative Insulin Treatment
Preoperative Creatinine higher than 2 mg/dL
90
Cardiac Evaluation - Minor predictors of risk
```
Age greater than 70
Abnormal EKG
LVH
LBBB
ST-T abnormalities
Abnormal rhythm: non-sinus
Uncontrolled systemic HTN
```
91
Cardiac Risk Stratification for Non-Cardiac Surgical Procedures
```
Vascular (High Risk - 5% risk)
Aortic and other major vascular surgery
Peripheral vascular surgery
Emergency surgery
Anticipated long procedures with fluid shifts or larger estimated blood loss
Intermediate Risk (1-5% risk)
Intraperitoneal and intrathoracic surgery
Carotid Endarterectomy
Head and Neck surgery
Orthopedic surgery
Prostate surgery
Low Risk (<1% risk)
Endoscopic procedures
Superficial procedures
Cataract surgery
Breast surgery
Ambulatory surgery
```
92
Indications for Pacemaker/AICD placement
Pacemaker
Sick Sinus Syndrome
3rd degree AV block
Symptomatic 1st or 2nd degree block
Non-ischemic, exercise induced block
Bradycardia associated with syncope or near syncope
Bradycardia associated with ventricular arrhythmia
Dilated Cardiomyopathies
Hypertrophic Cardiomyopathies
AICDs
Patients at high risk for fatal ventricular arrhythmias (ventricular tachycardia/fibrillation)
High risk for sudden cardiac death
Prior MI with ventricular tachycardia or ventricular fibrillation
Moderate to severe cardiomyopathies
93
Pacemaker nomenclature
```
Position 1 - Chamber being paced
Position 2 - Chamber being sensed
Position 3 - Response of device to a sensed event
O - no response
T - trigger device
I - inhibit device
D - dual, triggered and inhibited
Position 4 - Programmability and rate modulation
O - no programmability
R - rate modulation activated
Position 5 - Multi-site pacing
```
94
Aortic Valve area
Normal: 1.6 - 2.5 cm2
Mild AS: 1.0 - 1.5 cm2 (peak gradient <20)
Moderate AS: 0.8 - 1.0 cm2 (peak gradient >50)
Severe AS: <0.8 cm2 (peak gradient >50)
95
Aortic Stenosis - Management
Rhythm: sinus rhythm important to maintain atrial systole
Heart Rate: maintain normal HR (tachycardia and bradycardia harmful)
Preload: euvolemic, need adequate preload but too much can lead to pulmonary edema
Contractility: avoid decreases in contractility
Afterload: maintain SVR, drops can lead to profound hypotension and drop in coronary
perfusion pressure
96
Aortic Insufficiency - Management
Rhythm: slight tachycardia aids with forward cardiac output
Heart Rate: slight tachycardia aids with forward cardiac output
Preload: euvolemic, decreased preload leaves the dilated LV empty, too much fluid can
lead to pulmonary edema
Contractility: dilated LV can lead to decreased contractility
Afterload: slight drop in afterload can aid with forward flow
97
Mitral Stenosis - Management
Rhythm: sinus rhythm ideal to maintain EDV, however many of these patients have atrial
fib due to increase in atrial pressure and atrial stretch
Heart Rate: normal HR to allow for adequate diastolic filling time
Preload: maintain preload, a drop in preload leads to a significant drop in LV filling
Contractility: progressive disease can lead to drops in contractility
Afterload: maintain afterload, can't increase cardiac output across fixed stenosis with
drops in SVR
98
Mitral Insufficiency - Management
Rhythm: mild tachycardia and sinus, prone to a fib
Heart Rate: mild tachycardia to promote LV filling
Preload: normal levels
Contractility: advanced disease leads to ventricular dysfunction and worsening MI
Afterload: slight reduction in SVR allows forward flow, elevations in SVR can lead to
pulmonary edema
99
Cardiopulmonary Bypass - Anticoagulation
Heparin: 300 units/kg
Goal ACT: >400 seconds
Protamine reversal: 1 mg per 100 U of heparin
Heparin enhances anti-thrombin III - enhanced destruction of thrombin
If anti-thrombin III deficient (recent heparin treatment), need to replace AT-III for heparin
to be effective (FFP)
100
Protamine Reactions
1. Anaphylactic: based on prior exposure, fish allergies, diabetics using NPH, prior
vasectomy
Profound Vasodilation and cardiovascular collapse
2. Pulmonary Vasoconstriction: not well understood, lead to right heart failure
3. Histamine reaction: due to too rapid administration
Decrease in intravascular calcium
Decrease in SVR and hypotension
101
CEA - Neuromonitoring techniques
EEG
Advantages: available, reliable, correlates with cerebral ischemia
Disadvantages: Needs trained technician, possible anesthetic agent influences,
inability to detect subcortical ischemia
Processed EEG (BIS)
Advantages: available, identify severe cerebral ischemia, ease of use
Disadvantages: reliability, inability to detect focal ischemia
Somatosensory evoked potentials
Advantages: equivalent efficacy to EEG, detects deep brain structure injury
Disadvantages: complex, need for technician, can't use inhalational anesthetic
Transcranial Doppler
Advantages: ability to monitor cross clamp hypoperfusion and shunt malfunction,
ability to assess cerebral blood flow and embolic phenomena
Disadvantages: technical complexity, may require trained personnel
Cerebral Oximetry
Advantages: simple
Disadvantages: low sensitivity and specificity
Carotid Stump Pressure
Advantages: simple, lack of expense
Disadvantages: lack of validation, lack of critical CSP value
102
Cerebral Perfusion Pressure
CPP = MAP - ICP or CVP (whichever is greater)
103
Anesthetic Effects on Brain Physiology
Volatile: increase CBF, can lead to increase ICP due to vasodilation
Propofol: decreases CMR, CBF, and ICP, but can decrease MAP and thus CPP
Etomidate: decreases CMR, CBF, likely decreases ICP (mild vasoconstriction)
Benzodiazepines: decreases CMR, CBF, may decrease ICP
Opioids: minor reduction or no effect on CMR and CBF
Barbiturates: decreases CMR, CBF, ICP but can decrease MAP and thus CPP
104
Treatment of elevated ICP- step one
Positional therapy: elevated HOB to 30 degrees
Support hemodynamics: SBP >110 with goal MAP >90, CPP should be at a minimum of 70
Analgesia and Sedation: avoid increase in ICP from agitation
Avoid hypoxemia
Hyperventilation: PaCO2 30-35
Goal hematocrit >30%
Normothermia
105
Treatment of elevated ICP - step two and three
Drainage of CSF by surgeon
Osmotic therapy: Mannitol 0.25-1.0 g/kg. Furosemide 1 mg/kg. Hypertonic saline
Decrease IVF after replaced for diuresis from osmotic therapy
106
Treatment of elevated ICP - steps four and five
Barbiturate coma (for intractable elevations in ICP)
Neuromuscular blockade (only for short term)
Corticosteroids (reduces cerebral edema)
Decompressive craniotomy
107
Pathophysiology of Venous Air Embolism
Mechanical obstruction of pulmonary vasculature
Leads to hypoxemia, vasoconstriction, V/Q mismatch, increased pulmonary artery
pressure, and reduced cardiac output.
Release of vasoactive mediators - increased vascular permeability, pulmonary edema
Increased filling pressures, decreased cardiac output, hypotension, mill-wheel murmur
Airlock
108
Intracranial Hypertension Management (elevated ICP)
Hyperventilation
Osmotic diuresis
Barbiturates
CSF drainage
109
Cerebral Aneurysm - Intraoperative Goals
Avoid aneurysm rupture, maintain CPP, maintain transmural aneurysm pressure
Blunt sympathetic response to laryngoscopy
IV access: large bore IV, consider central line, avoid excessive fluids
Monitoring: standard ASA, arterial line, consider CVP or PAC
Avoid hypertension to avoid aneurysm rupture
Intracranial hypertension treatment: hyperventilation, osmotic diuresis, CSF drainage
Neurophysiologic monitoring
Induced hypotension
110
Subarachnoid hemorrhage and cerebral vasospasm
Develops 3-12 days after SAH, peak days 6-7
Diagnosis via angiography, transcranial doppler, or clinical progression
Prophylaxis and treatment
Nimodipine
Triple H therapy: hypertension, hypervolemia, hemodilution (not as common anymore)
111
Glasgow Coma Scale
```
Eyes open
Spontaneous 4
To Speech 3
To Pain 2
None 1
Best Verbal Response
Oriented 5
Inappropriate words 4
Incomprehensible sounds 3
Best Motor Response
Follows commands 6
Localizes pain 5
Withdrawal to pain 4
Flexion to pain 3
Extension to pain 2
None 0
```
112
SIADH - Etiology
Idiopathic
Post-operative
Central Nervous Disease: head trauma, tumors, CVA, delirium tremens
Neoplastic: lung, pancreas, ovary, lymphoma, thymoma
Endocrine: glucocorticoid insufficiency, hypothyroidism
Pulmonary: PNA, PPV, COPD
Medications: TCAs, SSRIs, Nicotine, MDMA
Infectious: CMV, mycobacteria, brain or lung abscess
113
SIADH - Signs and Symptoms
```
Anorexia
Nausea and Vomiting
Malaise
Headache
Confusion, stupor, coma
Seizures
```
114
SIADH - Differential Diagnosis
```
Adrenal insufficiency
Cerebral Salt Wasting Syndrome
CHF
DM
Hypopituitarism
Hypothyroidism
Nephrotic Syndrome
Polydipsia
Simple hyponatremia
```
115
SIADH - Testing and Diagnosis
Hyponatremia: <130 mEq/L
Plasma osmolality: <270 mOsm/kg
Urine sodium concentration: >20 mEq/L
Low: BUN, Cr, Uric Acid, Albumin
116
SIADH - Treatment
Treat underlying cause
Fluid (water) restriction: 800-1000 ml per day
IV Saline: for very symptomatic patients, hypertonic saline 200-300 ml over 3-4 hrs
Medications: diuretics, demeclocycline
Do not correct water balance rapidly
117
Cerebral Salt Wasting Syndrome
Hyponatremic dehydration due to intracranial pathology
Excessive renal sodium excretion from central process
Dehydrated and hypovolemic (unlike SIADH)
118
Cerebral Salt Wasting Syndrome - Testing
Hyponatremia
Dilute urine with high flow rate
Random urine sodium >40 mEq/L
Urine sodium excretion greater than intake
119
Cerebral Salt Wasting Syndrome - Treatment
Fluids
Correction of low sodium
Medications: mineralocorticoid (fludrocortisone)
120
Diabetes Insipidus
Hypernatremia with normal total body sodium concentration
Inability to concentrate urine
Renal resistance to ADH (nephrogenic)
Decrease in ADH secretion (central)
Excretion of large amounts of extremely dilute urine
121
Diabetes Insipidus - Etiology
```
Central
Traumatic: surgical, accidental
Neoplasm: lymphoma, craniopharyngioma
Granulomatous disease: sarcoidosis
Idiopathic
Infectious: meningitis, encephalitis
Vascular: cerebral aneurysms, Sheehans
Nephrogenic
Metabolic: hypokalemia, hypercalcemia
Infectious: pyelonephritis
Post-renal obstruction release
Vascular: sickle cell anemia
Granulomatous: sarcoidosis
Drug effects: lithium, amphotericin, demeclocycline, methoxyflurane
Genetic: X-linked, polycystic kidney disease
```
122
Diabetes Insipidus - Desmopressin Stimulation Test
Central: reduction in urine output and increased urine osmolality
Nephrogenic: no change in urine output and urine osmolality
123
Diabetes Insipidus - Treatment
```
Central
Desmopressin
Hydration
Nephrogenic
Diuretic: HCTZ
Indomethacin
Hydration
```
124
Oliguria - definition
Urine output <400 ml/day
| <0.5 ml/kg/hr for 6 hours
125
Acute Renal Failure - Risk Factors
```
Co-existing Renal Disease
Advanced Age
CHF
Symptomatic Cardiovascular Disease
Major Operative Procedure: CABG, Abdominal Aneurysm Repair
Sepsis
Multiple organ system dysfunction
Iatrogenic Causes: inadequate fluid replacement, delayed tx of sepsis, drugs
Hypotension
```
126
Acute Renal Failure - Prerenal
```
Absolute decrease in renal blood flow
Dehydration
Acute hemorrhage: hypovolemia, hypotension
GI fluid loss
Trauma
Surgery: mechanical restriction of renal blood flow (clamping)
Burns
Renal artery or vein thrombosis
Excessive Diuretic Use
Relative decrease in renal blood flow
Septic Shock
Hepatic Failure
Allergic reaction/transfusion reaction
Vasoconstriction
CHF
Decrease cardiac output
```
127
Acute Renal Failure - Renal
```
Acute glomerulonephritis
Goodpasture's
Wegener's granulomatosis
Acute lupus nephritis
Post-infectious glomerulonephritis
Berger's
Henoch-Schonlein purpura
Drugs: allopurinol, hydralazine, rifampin
Interstitial nephritis
Pyelonephritis
Sarcoidosis
Allergic drug reaction
Acute Tubular Necrosis
Ischemia: hypotension, shock
Embolic event or aortic cross clamp
Mechanical Damage: trauma
Nephrotoxic drugs
Solvents
Vasculitis
Chronic kidney disease: diabetes, hypertension
Multiple Myeloma
```
128
Acute Renal Failure - Postrenal
```
Upper urinary tract obstruction
Renal pelvis
Ureter
Lower urinary tract obstruction
Bladder outlet
Foley catheter
Urethral
Prostatic hypertrophy or cancer
Cervical cancer
```
129
Correction of sodium deficit
Dose = weight (kg) x (140-current Na concentration) x 0.6
Correct at rate of 0/6-1.0 mmol/L/hr until Na is 125 mEq/L
Replace half of the deficit over first 8 hours, rest over the next 1-3 days
130
Fasting Guidelines
```
Clear liquids: 2-3 hours
Breast milk: 4 hours
Infant formula and non-human milk: 6 hours
Light meals: 6 hours
Regular meals: 8 hours
Fried and fatty foods: >8 hours
```
131
Pheochromocytoma: pre-operative
Identify tumor location
Alpha blockade
Beta blockade considered, needs to be started after alpha blockers
10-14 days of treatment, proceed with surgery when:
BP consistently below 160/90
No orthostatic hypotension
No ST-T changes on EKG
Consider pre-operative volume loading
Consider co-morbid conditions: cardiomyopathy
132
Pheochromocytoma: intra-operative
Pre-operative sedation
General, regional, and combined techniques have been used
Judicious use of histamine releasing drugs and sympathomimetics
Pre-induction arterial line
Short acting hypotensive agents on hand: esmolol, nitroprusside, nicardipine
IV lidocaine to blunt laryngoscopy response
Magnesium: vasodilator and they are often depleted
Slow induction
Manipulation of tumor may cause spikes in BP
BP may fall precipitously when tumor blood supply ligated
133
Thyroid Storm - treatment
```
Propylthiouracil (PTU)
Supportive measures for fever: acetaminophen, cooling blankets
IV fluids
Sodium iodide
Hydrocortisone
Meperidine (for shivering)
Digoxin (for heart failure)
Propranolol or esmolol
```
134
Hyperthyroidism - treatment
```
Euthyroid before surgery
Non-emergent
PTU, methimazole (both may take 6-8 weeks)
Radioactive iodine
Surgery
Glucocorticoids
Emergent
Beta Blockers
```
135
RSI Indications
```
Full stomach: <8 hours fasting
Unknown last oral intake
Morbid obesity
Severe GERD
Decreased GI motility
Intra-abdominal process
Trauma
Pregnancy
Decreased gag reflex or depressed mental status
```
136
RSI Contraindications
Difficult Airway
Contraindication to succinylcholine
Cervical Spine Injury
137
Delayed Emergence, Altered Mental Status - Differential Diagnosis
Hypoxia and Hypercarbia
Hypotension
Hypothermia
Residual medications and polypharmacy: muscle relaxants, volatiles, opioids, induction
drugs, pre-medications, scopolamine, ketamine, steroid psychosis, cardiac anti-
dysrhythmics, TCAs, antihistamines
Electrolyte abnormalities: DKA, hyper and hypoglycemia, hyponatremia,
hypermagnesemia, acidosis/alkalosis, hypercalcemia
Adverse neurologic outcome
Infections
Substance abuse
Endocrine abnormalities: Addison's, Cushing's, Hyper/hypothyroid
Renal abnormalities
Pain and anxiety
138
Delayed Emergence, Altered Mental Status - Evaluation
Check oxygenation and ventilation
Check vital signs
Review medications
Investigate pre-operative level of consciousness
Check patient's response to stimulus
Pharmacological reversal agents
Naloxone: 0.04 mg IV, repeat every 2 minutes up to 0.2 mg
Flumazenil: 0.2 mg IV per minute to total of 1 mg
Physostigmine: 1.25 mg IV
Reversal of neuromuscular blockers
Consider LAST
Check ABG, electrolytes, and blood glucose
Perform neurological check
Head CT scan and neuro consult
139
Post Carotid Bleed - Causes of Respiratory Insufficiency
Recurrent laryngeal nerve injury
Hypoglossal nerve injury
Massive Hematoma
Deficient Carotid Body function - loss in ventilatory drive
140
Nausea and Vomiting - Differential Diagnosis
```
Hypoxia
Hypotension
Pain
Anxiety
Infection
Chemotherapy
GI obstruction
Narcotics, volatiles
Movement
Vagal Response
Pregnancy
Increased ICP
PONV
```
141
Malignant Hyperthermia - Treatment Intraoperative
Call for Help, Call MH Hotline
Discontinue triggering agent
Change circuit
Hyperventilate with 100% O2
Dantrolene: 2-3 mg/kg IV bolus every 5 minutes up to 10 mg/kg.
Then start infusion of 1-2 mg/kg/hr.
Treat Acidosis: Sodium Bicarbonate
Cool patient
Monitor UOP: goal >1-2ml/kg/hr. Use IV fluids, furosemide, mannitol
Obtain labs: ABG, electrolytes, CK, hepatic functions, coag panel, CBC, glucose
Treat Hyperkalemia: Insulin 0.1-0.2 U/kg and Dextrose 500 mg/kg and calcium
Treat arrhythmias
Expedite or abort surgery
Consider arterial line and central line
142
Malignant Hyperthermia - Treatment Postoperative
```
Alkalinize the urine and diurese
Follow CK levels
Follow all labs
Watch for DIC
Follow CNS status
Continue dantrolene 1 mg/kg IV q 4-6 hours for up to 72 hours
```
143
Interscalene Block
Indications: shoulder, upper arm, lower arm
Shortcomings: Can spare C8 and T1 (ulnar nerve), potentially harmful in COPD
Complications: PTX, spinal or epidural block, vertebral artery, hoarseness (more often in
right sided, 10-20%), phrenic nerve paralysis (near 100%), cervical plexus blockade,
Horner's syndrome (Miosis, Ptosis, Nasal Stuffiness, Anhidrosis)
144
Supraclavicular Block
Indications: upper arm, lower arm, NOT shoulder
Shortcomings: avoid bilateral due to risk of PTX and phrenic nerve injury
Complications: PTX, phrenic nerve block
145
Infraclavicular Block
Indications: upper arm, lower arm, NOT shoulder
Shortcomings: may involve multiple injections to get musculocutaneous
Complications: PTX
146
Axillary Block
Indications: forearm, wrist, hand
Shortcomings: may need multiple injections to get musculocutaneous and
intercostobrachial and medial brachial cutaneous, arm must be abducted to perform
Complications: none specific to this block
147
Lumbar Plexus Block
Indications: femoral neck/shaft, anterior thigh, knee
Shortcomings: very vascular area
Complications: retroperitoneal hematomas, epidural spread, LAST, hip flexor weakness
148
Femoral Nerve Block
Indications: knee
Shortcomings: need for sciatic (popliteal) and/or obturator (medial thigh) to completely
cover knee, quadriceps weakness
Complications: accidental puncture/injury of peritoneal space
149
Sciatic Nerve Block (popliteal)
Indications: sole of the foot and below knee
Shortcomings: likely require lumbar plexus, femoral, or saphenous nerve blocks as well
Complications: no specific complications
150
CRPS
```
Type I: not associated with a major nerve injury, non-dermatomal distribution
Type II: associated with a major nerve injury, dermatomal distribution
Treatment:
1. Physical therapy
2. NSAIDs
3. Opioids
4. Steroids (acute phase of condition)
5. SSRIs and TCAs
6. Lidocaine (IV), maybe patches
7. Gabapentin
8. Clonidine patches
9. Ketamine
10. Sympathetic blocks (stellate ganglion, lumbar)
11. TENS unit
12. Spinal Cord Stimulator
13. Psychiatric Treatment
```
151
Hyperthermia - Differential Diagnosis
Iatrogenic
Infectious
Pulmonary (aspiration pneumonitis, atelectasis, DVT/PE)
Metabolic (pheochromocytoma, thyroid, adrenal insufficiency)
Central Nervous System (status epilepticus, hypothalamus, Parkinson's)
Drug induced (MH, Neuroleptic Malignant Syndrome, Anticholinergic effect, Cocaine,
TCAs, MOAIs)
Blood transfusion
152
Hypothermia - Differential Diagnosis
```
Environmental
Impaired Thermoregulation
Medical Conditions (hypothyroidism, large BSA burns, malnutrition, hypoglycemia,
hypothalamic, unconsciousness)
Iatrogenic
```
153
Myasthenia Gravis - Anesthetic Implications
Resistant to depolarizing neuromuscular blockers (unless receiving treatment)
Sensitive to non-depolarizing neuromuscular blockers (unless receiving treatment)
154
Sickle Cell Crisis Triggers
```
Low oxygen saturation
Acidosis
Hypo/hyperthermia
Infection
Emotional Stress
Physical Exertion
Alcohol Consumption
Dehydration
Surgery
```
155
Complications of Massive Transfusion
Hypothermia
Volume Overload
Dilutional Coagulopathy (decrease in fibrinogen, FII, FV, FVIII, platelets)
Left shift of Oxygen-Hgb dissociation curve (due to decrease in 2,3-DPG)
Citrate intoxication (hypotension, narrow pulse pressure, elevated CVP)
Hyperkalemia
Acid-base disturbances
156
Remote Anesthesia Guidelines
Reliable oxygen source and back up E cylinder
Suction source
Waste gas scavenging system
Adequate monitoring that complies with ASA standards
Self-inflating resuscitator bag
Adequate anesthetic drugs and supplies
Sufficient safe electrical outlets
Adequate light and battery powered backup
Sufficient space
Emergency cart with defibrillator, emergency drugs and equipment
Means of reliable two-way communication
Compliance with safety and building codes
Adequately trained staff to support anesthesia team
Adequate equipment for transport
Post-anesthesia care facilities
157
Remote monitoring guidelines
Qualified anesthesia personnel
Continuous monitoring of oxygenation, ventilation, circulation, temperature
Oxygen concentrations of inspired gas, low oxygen concentration alarm
Blood oxygenation: pulse ox
Ventilation: observation, ETCO2, disconnect alarm
Circulation: EKG, BP every 5 minutes, pulse ox
158
MRI Anesthetic Equipment
Anesthesia cart (pediatric or adult)
Anesthesia machine/circuits (pediatric or adult)
Monitors for transport
End-tidal CO2 monitor
Temperature monitor
MRI-compatible monitoring equipment
Airway equipment (oral and nasal airways, nasal cannula, masks, LMAs, ETTs)
Long corrugated ventilation tubing
Self-inflating resuscitator bag
Syringe pump and extension sets
Medications (propofol, remifentanil, ketamine, midazolam, fentanyl, succinylcholine, non-
depolarizing muscle relaxants, ephedrine, other emergency drugs)
IV tubing and fluids
Charting supplies
