Anesthetic Physiology And Principles Flashcards
1
Q
What is the cause of rapid reduction in core temperature during the first hour of general anesthesia?
A
Redistribution of heat from the core to the periphery
2
Q
What are the 2 mechanisms of undesired heat loss in the OR?
A
- Impaired thermoregulation secondary to anesthesia
2. Low ambient temperature of the operating theater
3
Q
What are the 2 main “physic” ways that heat is lost in the OR.
A
- Radiative (67%)
- Evaporative (17%)
- Conductive and convective (16%)
4
Q
How can you prevent heat loss from a patient?
A
By pre-warming them
5
Q
How much does general anesthesia decrease FRC?
A
10%
6
Q
How much is FRC reduced by lying flat?
A
10-15%
7
Q
What happens when people go to higher altitude?
A
Increased respiratory rate to compensate for the decrease in oxygen
Increased cardiac output (returns to normal later)
Increase in Hgb over time (by decrease in plasma concentration, increase in erythropoeitin)
Rightward shift in oxygen dissociation curve ( due to hypoxia, increased 2,3-DPG
Increased hypoxic pulmonary vasoconstriction
8
Q
What happens to the physiology of the respiratory system when a patient is main stemmed?
A
Shunting occurs
There is no increase in dead space
9
Q
What are the 6 factors that influence the level of spinal anesthesia?
A
- Dose/concentration
- Site of injection
- Baricity of local anesthetic
- Posture of patient
- Volume of CSF
- Density of CSF
10
Q
In what conditions is the volume of CSF reduced?
A
Anything that increases intra abdominal pressure: Ascites Obesity Pregnancy Tumor
11
Q
What is the best clinical sign of reversal?
A
Sustained head lift
12
Q
What is the least greatest sign of reversal?
A
Tidal volume
13
Q
What are the recommended points of recovery?
A
Sustained tetany for 5 seconds to a 100 Hz stimulus
Sustained head or leg lift in awake patients
14
Q
What anesthetic technique has not been associated with exacerbation of symptoms or side effects in MS?
A
Epidural anesthesia
15
Q
What are the effects of citrate intoxication?
A
Hypocalcemia Myocardial depression Hypotension Hypomagnesemia (chelated along with calcium) Coagulopathy
16
Q
What blood product carries the most citrate.,
A
FFP and platelets
17
Q
In what conditions is citrate toxicity more likely?
A
Hypothermia
Liver disease
Hyperventilating
Pediatrics
18
Q
What are the signs of citrate toxicity?
A
Hypotension
Narrow pulse pressure
Increased EDP
Increased CVP
19
Q
How is citrate metabolized?
A
Rapidly by the liver
20
Q
When do ionized calcium levels begin to decrease when transfusing blood?
A
When blood is given at 6 units/hr
21
Q
What is the treatment of citrate toxicity?
A
Calcium
22
Q
What are the effects of citrate intoxication?
A
Hypocalcemia Myocardial depression Hypotension Hypomagnesemia (chelated along with calcium) Coagulopathy
23
Q
What blood product carries the most citrate.,
A
FFP and platelets
24
Q
In what conditions is citrate toxicity more likely?
A
Hypothermia
Liver disease
Hyperventilating
Pediatrics
25
What are the signs of citrate toxicity?
Hypotension
Narrow pulse pressure
Increased EDP
Increased CVP
26
How is citrate metabolized?
Rapidly by the liver
27
When do ionized calcium levels begin to decrease when transfusing blood?
When blood is given at 6 units/hr
28
What is the treatment of citrate toxicity?
Calcium
29
What changes would you see with a venous air embolism?
Decreased pulmonary perfusion so decreased ETCO2 with increased PaCO2 due to more dead space
30
What is the best way to increase FRC in a patient in steel trendelenburg?
Increase PEEP because it increases the volume of air in the lungs
31
What is citrate used for in blood?
Anti coagulation by binding calcium which prevents calcium from binding to factor IV which prevents coagulation
32
How long does it take the kidneys to eliminate the bicarbonate from citrate?
3-4 days
33
Why do infants have a faster rate of induction compared with adults?
Because they have a higher minute ventilation to FRC ratio
Their FRC is lower
34
At what age does MAC requirement reach a peak
6 months
35
What does glucagon do to the heart?
Increases contractility by increases camp which increases intracellular calcium so increases inotropy and chronograph
36
What drug should you avoid using in someone receiving bleomycin?
Lidocaine because it can enhance its cytotoxicity
37
What should be limited in patients receiving bleomycin?
FiO2 because it can aggravate the pneumonitis
38
What chemotherapy drugs are not good for doing regional anesthesia?
Vincristine and vinblastine because they cause peripheral neuropathy
39
How does mannitol work?
Osmotic Diuresis by being freely filtered by the glomerulus but poorly up taken by the vasculature so it sets up a hypertonic gradient drawing fluid into the tubule
40
How is mannitol renal protective?
Maintains patency of flow and flushes debris from the tubule
Also transiently sets up osmotic gradient in the vasculature so increasing circulating plasma volume
41
What are the carotid body chemoreceptors primarily responsive to?
Arterial partial pressure of oxygen
42
When do the carotid bodies start firing?
When PaO2 falls below 60-65 mmHg via the glossopharygneal nerve to increase minute ventilation
43
How is CO2 transport d in the blood?
As dissolved CO2, bicarbonate and carbamino compounds
Majority = bicarbonate
44
What is the mechanism by which hyperbaric oxygen works?
It increases PaO2 thereby increasing the oxygen content of the blood by increasing the amount dissolved in plasma
Because the amount dissolved in plasma = paO2 X .003
45
At what level of PaO2 is the saturation of oxygen 100%?
100 mg
46
How much oxygen do tissues at rest extract?
5-6 ml/dL
47
At what FiO2 and atmospheric pressure do you get sufficient O2 requirement without contribution from hemoglobin?
FiO2 of 100% at 3 am
48
What is Henry's law?
At a constant temperature, the amount of gas dissolved in liquid is proportional to the partial pressure of the gas
49
What is Boyle's law?
At a constant temperature, the volume of gas is inversely proportional to the pressure
This is how hyperbaric oxygen therapy works in air embolism
50
What mediates bradycardia?
Carotid sinus barorerceptor stimulation causing SNS inhibition
51
How does the carotid sinus work?
Afferents nerves go to glossopharygneal nerve (activated by stretch)
Activation leads to signaling to nucleus solitarius which inhibits sympathetic innervation from spinal cord and stimulates PNS to stimulate vagus nerve
52
When is the RV perfused in the cardiac cycle?
Diastole and systole due to the lower right heart pressures
53
What does angiotensin II do to GFR?
It increases it by constricting the efferent arteriole in states of hypovolemia
54
What does renin cause?
Cleavage of angiotensinogen to angiotensin I
55
What is myotonic dystrophy?
Delayed muscle relaxation after contraction
Other associations:
Gastric atony, thyroid dysfunction, cardiac conduction abnormalities, myopathy, MVP, diabetes, adrenal insufficiency
56
What are the symptoms that occur due to autonomic activity during ECT?
Increased ICP
| Increased PSNS initially after seizure followed by a sympathetic surge
57
In myasthenia gravis, how do you need to change your succinylcholine dose?
It will need to be increased due to a decreased number of functional acetylcholine receptors
58
In MG, what will you need to do to your NMB dose?
Decrease it
59
In Lambert-Easton syndrome, what will you need to do to your succinylcholine dosing?
Decrease it because patients are sensitive to muscle relaxants
(Decreased Ach release so increased extrajunctional receptors due to low calcium influx all the time and therefore low Ach release)
60
How much more affinity does CO have for hemoglobin than oxygen?
200-300 times
61
How does CO shift the oxygen-hemoglobin dissociation curve?
Leftward
62
What kind of ph abnormality does CO cause?
Anion gap metabolic acidosis due to lactic acidosis from leftward shift of curve
63
Why is tachypnea a late sign in carbon monoxide poisoning?
Because the carotid bodies respond to PaO2, which is not affect in CO
64
What are the cardiac effects of CO?
Direct depression because CO binds to cardiac myoglobin even more than hemoglobin
65
What is PaO2 a function of?
Alveolar O2 (therefore FiO2, atmospheric pressure, and DLCO)
66
In what conditions is PaO2 normal?
Methemoglobinemia
Carbon monoxide poisoning
Severe anemia
67
What is a common pulse ox reading in methemoglobinemia?
85%
68
What are strong ions?
```
Sodium
Chloride
Potassium
Magnesium
Calcium
(Lactate, sulfate, ketoacids, nonesterified fatty acids)
```
69
What is the concept of the strong ion difference?
It proposes that plasma ph is determined by 3 independent factors: PCO2, SID, Atot (total plasma concentration of nonvolatile buffers)
70
What are the nonvolatile buffers in the body?
Albumin
Globulins
Inorganic phosphates
71
What is the strong ion differences?
It represents the difference between the charge of plasma strong cations (sodium, potassium, calcium magnesium) and anions
72
What is the normal strong ion difference?
40-44 mEq/L
73
What happens with rapid administration of normal saline?
Hyperchloremic non anion gap metabolic acidosis and a decrease in SID
74
What other condition can cause hyperchloremic metabolic acidosis?
Severe diarrhea (loss of isotonic fluid rich in bicarbonate)
Loss of bicarbonate is counteracts by an increase in chloride
75
What are the classic lab findings in SIADH?
Low sodium with a urine sodium greater than 20 and increased urine osmolarity, decreased plasma osmolarity
76
Why is urine sodium high in SIADH?
The kidney attempts to excrete the excess fluid through increased natriuresis in response to the decreased plasma osmolarity
77
What is the haldane effect?
The relationship between carbon dioxide dissociation curve and oxyhemoglobin
78
What is the Bohr effect?
The binding effect of H to Hemoglobin chains and the oxygen release and dissociation thereafter
79
What does Gs do?
GDP binds GTP then dissociates and stimulates adenylyl cyclase to convert ATP to cAMP which binds subunits that release subunits of protein kinase A which stimulates release of calcium from the sarcoplasmic reticulum
80
Which hormones work by Gs?
```
Glucagon
Beta adrenergic a
Dopamine
V2
Anterior pituitary hormones
Prostacyclin can receptor that inhibits platelet aggregation
```
81
What does increased cAMP cause?
```
Bronchodilation
Vasodilation
Increased contractility
Lipolysis
Glycogenolysis
```
82
What does ECT do to cerebral blood flow and ICP?
Increases them
83
How does ECT work?
Delivers an electrical stimulus to induce a seizure of at least 25 seconds
84
What are the side effects of ECT?
```
Headache
Myalgias
Status epilepticus
MI
Fractures
HTN
Long term memory loss
Bradycardia
```
85
How is norepinephrine inactivated?
By degradation in the pulmonary endothelium
86
What does cortisol do to electrolyte homeostasis?
It facilitates sodium transport
Inhibits GI sodium loss
Enhances Na/K exchange and renal potassium secretion
87
How do thyroid hormones influence potassium?
Promote direct cellular uptake
88
In a healthy young adult, plasma volume comprises approximately what percentage of extracellular volume?
20%
89
In a healthy young adult, plasma volume comprises approximately what percentage of intracellular volume?
40%
90
In a healthy young adult, interstitial volume comprises approximately what percentage?
80% of ECV
91
What is the difference between CSW and SIADH?
In CSW, the patients are hypovolemic.
92
What is the problem in CSW?
Inappropriate renal salt wasting
93
What is the treatment of CSW?
Replacement of free water and sodium
94
What factors offset the decrease in PaCO2 in acute mountain sickness?
Increase in CSF bicarbonate in response to reduction in OaCO2, and increase in hydrogen ions and Co2 in the CSF
This will correct after several days when the bicarbonate in CSF crosses into the blood leaving the chemoreceptors to deal with the hypoxia
95
What is high altitude pulmonary edema caused by?
Increased pressure in the pulmonary vasculature from hypoxic vasoconstriction
96
What is used as prophylaxis against high altitude pulmonary edema?
Nifedipine
| B2 agonists
97
What is hi altitude cerebral edema caused by?
Increased CBF due to hypoxia
98
What is the treatment of high altitude cerebral edema?
Immediate descent and high FiO2
99
How does the chloride shift work?
When CO2 enters the RBC, it combines with water to form carbonic acid, then dissociates to hydrogen and bicarbonate
The bicarbonate diffuses out and chloride shifts in to maintain electrical neutrality
100
What Happens to the ions in RBC in lungs?
The oxygen causes hemoglobin to have less affinity for the hydrogen ion. It dissociates and combines with bicarbonate to form CO2 and water. (Haldane effect)
CO2 diffuses out and is exhaled
101
How does helium help deliver O2 in bronchospasm?
Helium is less dense and has a smaller Reynolds number (less likely to be turbulent) creates more laminar flow because causes gas mixtures to be less dense
102
What is th Venturi effect?
An increase of velocity of air through a constricted area which causes a decrease in pressure which results in more air in the lungs
103
How do you treat diabetes pre operatively?
Tell them to take half of their usual long acting insulin or intermediate acting
104
What is the hallmark of lambert Easton syndrome?
Muscle weakness that improves with use
105
What is the hallmark of myasthenia gravis?
Muscle weakness worsened by usage and improved with rest
106
What are the electrolyte abnormalities in Addisons?
```
Hypercalcemia
Hyponatremia
Hyperkalemia
Hyperchloremic metabolic acidosis
Hypoglycemia
```
107
Why is there hypercalcemia in Addison's disease
Due to decreased GFR due to hypovolemia from adrenal insufficiency
Increased release of calcium from bone
108
What is the most common cause of strider after thyroidectomy in the first 24-96 hours?
Hypocalcemia
109
What cardiac manifestations does hypocalcemia cause?
Prolonged QT due to slower ventricular repolarization
Heart block
Torsades
110
What is the renal mechanism for regulating plasma osmolality?
Vasopressin release mediated by carotid barorerceptors
111
What is a thermal neutral zone?
The temperature range at which a naked person's heat loss matches heat production from basal metabolic rate.
This is when heat loss occurs without sweating
112
What is the thermal neutral zone for a naked newborn?
32-35 Celsius
113
What is the thermal neutral zone for an adult?
26-28 Celsius
114
What will happen below the thermal neutral zone?
Metabolic rate will increase
115
What is an ASA 4?
Someone with a condition that is a constant threat to life
116
What is an ASA 3?
Someone with severe systemic disease
117
What is an ASA 5?
Someone who will die without intervention
Or organ damage has already happened
Septic shock, gangrene, uncontrolled bleeding
118
What schedule of drug is ketamine?
3
119
What are schedule 1 drugs?
Drugs with very high potential for abuse with no accepted medical use (heroin)
120
What are hetastarches?
Amylopectin colloids
121
What are hetastarches associated with?
Coagulopathy (dilution all reduction of Factor 8:C and vwf by 50-80%
Prolong PTT
Decreased platelet adhesions and clot formation by decreasing IIb/IIIa
Decreased strength of clot due to polymers moving into it
Renal failure
122
What conditions are hetastarches contraindicated
Renal failure
| Vwf
123
Do tetrastarches cause more or less coagulopathy than heta
Less
124
What is the main component affected in FRC with obesity?
Expiratory reserve volume
125
What percentage of total body weight is lean body weight?
80% for males
| 75% for females
126
What percentage of total body weight is lean body weight?
80% for males
| 75% for females
127
What happens to albumin in burn patients?
Catabolism of amino acids and proteins such as albumin occurs --> hypoalbuminemia
128
What drugs need to be reduced in dosing in burn patients?
BZDs due to hypoalbuminemia because they are highly bound to albumin so decreasing this concentration increases their free fraction
129
What drugs need to be increased in dosing in burn patients?
Beta blockers and local anesthetics due to less availability in the setting of hypoalbuminemia and less alpha 1 glycoprotein
130
What other drugs have an increased free fraction in burn patients, but do not require reduced dosing?
Opioids - highly albumin bound
They do not require reduced dosing due to the amount of pain associated with burns and therefore the increased tolerance these patients develop
131
What happens to the effect of NMBs in a burn patient?
There is a resistance due to an increase in Ach receptors including the immature isoform, increased renal excretion and decreased protein binding of the drug
132
When does resistance to NMBs happen?
1 week after burns, peaking at 5-6 weeks.
133
What happens to insulin resistance in a burn patient?
There is a huge catecholamine and glucagon surge in patients with burns >10% and therefore significant insulin resistance.
134
How long is succinylcholine contraindicated in a burn patient?
From 24 hours - 1 year
135
What are the major criteria for fat embolism syndrome?
1. Subconjunctival or axillary petechiae
2. Hypoxemia
3. CNS depression
4. Pulmonary edema
136
What are the minor criteria for fat embolism syndrome?
Tachycardia, Hyperthermia, Decreased platelet/hct, fat globules in urine, sputum, retina, increased ESR
137
What is the maximum dosing of lidocaine you can give for tumescent liposuction?
55 mg/kg because most of the solution is aspirated back
138
How long should you wait before giving any more local anesthetic after liposuction?
12-18 hours
139
What are the risks of tumescent liposuctin?
Fluid overload, LAST
140
What is the biggest predictor of a difficult intubation in a morbidly obese patients?
A large neck circumference
141
How can you minimize the likelihood of an exacerbation of MS with anesthesia?
maintain normothermia
The risk goes up significantly with 1 degree drop
142
What is the evidence on inhalational anesthetics and pregnant providers?
Only Nitrous oxide affects a fetus.
There seems to be a slight increased risk of spontaneous abortion in providers.
143
What happens to beta receptor sensitivity and circulating catecholamine levels with aging?
The catecholamine levels are elevated so beta receptor agonism is desensitized and the elderly have less of a response to stress.
144
Why are the elderly more reliant on atrial kick?
Because diastolic dysfunction of the heart makes the passive filling phase less effective due to a decreased pressure gradient from the atrium to the ventricle since the ventricle cannot relax. They become dependent on the atrial kick for stroke volume
145
Who is at risk for ulnar neuropathy?
Obese or thin, male, prolonged bed rest, positioning problems
146
When does ulnar neuropathy show up?
24-72 hours postoperatively
147
How long does it take for a nerve to heal?
4-6 weeks
148
What do nerve conduction studies show?
Sensory and motor deficits
149
What does it mean if a patient wakes up complaining of nerve pain?
The nerve damage was likely there preoperatively
150
What does cricoid pressure do to LES tone?
Decreases it
151
What does succinylcholine do to LES tone?
Increases it
152
What drugs increase LES tone?
Histamine
Serotonin
Metoprolol
Cholinergics
153
What nerve palsies do LMAs cause?
Lingual nerve, hypoglossal, recurrent laryngeal
154
What are the risk factors for nerve palsies and LMAs?
Prolonged surgery >2-4 hours, lidocaine jelly use, nitrous oxide, overinflation of a small fitting cuff,
155
What are the symptoms of lingual nerve palsy?
Tongue numbness, oropharyngeal swelling, difficulty phonating,
156
What are the fasting rules for surgery?
2 hours - clear liquids
4 hours- breast milk
6 hours- light meal or human milk, formula
8 hours- real meal, fatty foods
157
What drugs worsen inhalational inductions?
Opioids because they cause apnea
158
What happens to spontaneous breathing with inhalational induction?
It is preserved up to a point so patients will regulate their own depth of anesthesia.
159
Why is sevoflurane the choice for inhalational induction?
Does not cause salivation
| Is not associated with Stage II excitation
160
What drugs improve inhalational induction?
BZDs
161
What food allergies are associated with latex allergies?
Banana, avocado, kiwi, mango, pineapple
162
Why are people who use detergents, toothpaste and shampoo at higher risk for allergic reaction to rocuronium, vec, pan?
Because these products contain quaternary ammonium ions that resemble the aminosteroid NMBs
163
What is bone cement implantation syndrome
Hypoxia
Hypotension
Cardiac arrythmias
Increased pulmonary vascular resistance
164
What are the grades of bone cement implantation syndrome?
Grade 1: SpO2 < 94% or hypotension
Grade 2: SpO2 < 88% or SBP fall >40%, unexpected LOC
Grade 3: Cardiac arrest
165
What conditions have to be met for PPV to be most accurate?
1. Controlled ventilation
2. Tidal volumes of 7-8ml/Kg (IBW)
3. No PEEP
4. No cardiac arrythmias
5. No big changes in chest or lung compliance (laparoscopic procedures, open chest)
166
What is the pathophysiology of bone cement implantation syndrome?
Increased intramedullary pressure leading to embolization of fat, bone, cement, platelets, fibrin, air
167
What happens in phase 0 of a muscle depolarization?
Influx of sodium
168
What happens in phase 1 of muscle depol
Transient efflux of potassium
169
What is phase 2 of muscle depol?
Net influx of calcium which causes plateau
170
What is phase 3 of muscle depol?
Significant efflux of K
171
What does epidural anesthesia do to pulmonary mechanics?
Can decrease peak expiratory pressure by 40%
| Decreases FEV1 and vital capacity by 10% in lumbar or low thoracic. High thoracic causes 20-30%
172
Why is peak expiratory pressure affected in epidural anesthesia?
Because it relies on abdominal muscles primarily
173
How does a variable bypass chamber work?
A carrier gas goes through the chamber and picks up the anesthetic vapor.
A certain percentage of volatile is delivered to the patient depending on how much fresh gas flow passes through the vaporizer chamber
174
What causes bradycardia in intrathecal injection?
High baseline vagal tone
Anesthetic levels above T5
Decreased preload
175
Why does decreased cardiac preload cause bradycardia?
Decreased stretch of myocardium so intrinsic depolarization of SA node slows
176
What is the Bainbridge reflex?
Stretching of the myocardium causes increased heart rate
177
What happens in digitalis toxicity with hypokalemia?
There is reduced binding to potassium ions with the Na-K-ATPase pump so it causes worsened pump inhibition due to digitalis
178
What may happen with digitalis in the setting of hypomagnesemia or hypercalcemia?
Toxic levels of intracellular calcium leading to ventricular arrhythmias
179
In what surgeries should ASA be held?
```
Intracranial
Middle ear
Posterior eye
Intra medullary spine
Prostate
```
180
Which surgeries should ASA be continued?
Major vascular
181
When do the most serious cases of CO2 embolism happen?
In the beginning of the procedure due to the Veress needle being put into a vein or organ
182
Will CO2 emboli expand if the patient is in N2O?
No because CO2 is more soluble than nitrous
183
What are the four sites known to be reflective of core temperature?
Esophageal
Tympanic
Pulmonary artery
Nasopharyngeal
184
What 2 things can cause an acute and excessive increase in PaCO2 and EtCO2 with rapid administration?
Dextrose
| Bicarbonate
185
What is Hoffman elimination?
A quaternary ammonium group is converted to a tertiary amine by cleavage of a carbon-nitrogen bond,
186
What increases the speed of Hoffman elimination?
Increased ph and increased temperature
187
What P450 enzymes does St. John's Wort induce?
3A4 and 2C9
2C9: NSAIDs
3A4: alfentanil, midazolam, lidocaine, oral contraceptives
188
What factors stimulate the release of vasopressin?
Pain, nausea, hypoglycemia, increased plasma osmolality, stress, pregnancy, nicotine
189
What factors inhibit release of vasopressin?
Cortisol
Increased circulating volume
Caffeine
Hypo-osmolality
190
How does vasopressin stimulate vasoconstriction?
By activating G protein and phospholipase C --> release calcium from SR
191
What is the half life of vasopressin?
15-20 minutes
192
How does vasopressin stimulate water resorption?
Increasing intracellular levels of cAMP and activating protein kinase A
193
Why are burn patients resistant to NMBs?
Because they have an up regulation of receptors and higher protein binding so there is less free drug to bind more receptors
194
Why do burn patients need a decreased dose of miva curium?
Because they have less pseudocholinesterase and this is how miva curium is broken down
195
What nerve needs to be blocked for lateral bladder wall tumor?
Obturator to avoid the jerk reflex
196
What influences spread of local anesthetic in epidural?
Age: more spread due to more dura permeability, more patency since less fat in the space, more compliance
PEEP
Volume of local
Mass of local
197
What is anterior spinal cord syndrome?
Loss of motor, pain, temperature
Proprioceptiom is intact
198
What type of patients are at higher risk for new or worsened nerve injury after spinal anesthetic?
Patients with space occupying lesions or spinal stenosis
199
Which nerves are the fastest conducting for pain?
A-delta
200
What imaging should be used to diagnose a retained epidural catheter?
CT
201
What do you do if an epidural catheter is difficult to remove?
Flex the patient
Inject saline into the catheter
Used a tongue blade and have patient move around some
202
What problems can you have with administering anesthesia to patients with ankylosing spondylitis?
Difficult intubation due to inability to move their neck
Difficult ventilation due to pulmonary fibrosis
Epidural hematoma due to multiple attempts and platelet dysfunction due to NSAID use
203
What should you avoid using if a patient is on bleomycin?
High FiO2 because the pulmonary toxicity associated with bleomycin depends on this
204
What chemotherapy drugs affect the peripheral nervous system?
Vincristine, cisplatin
205
What is the biggest predictor for difficult intubation in morbid obesity?
Increased neck circumference
206
When does the most amount of heat loss happen in the OR?
During the first hour of anesthesia
207
What are the consequences of hypothermia?
Coagulation defects
Wound infection/healing
Impaired drug metabolism
MI due to shivering and increased oxygen consumption
208
What should the operating room temperature be to maintain normothermia?
23-25 degree Celsius
