Anesthetic Complications Flashcards
what can cause low heart rate?
drugs
patient
procedure
what causes vasodilation in anesthesia?
inhalant
acepromazine
propofol
how do anesthetic drugs cause relative hypovolemia?
venodilation: venous circulation already holds the majority of the blood volume
what is relative hypovolemia?
normal blood volume, but volume (capacity) of vascular compartment has increased
what is the equation for mean arterial pressure?
MAP = HR x SV x SVR
what can you do to alleviate absolute hypovolemia?
decrease inhalant
crystalloid bolus
replace volume loss if due to hemorrhage
what can you do to alleviate poor cardiac contractility?
decrease inhalant
positive inotrope: dobutamine
administer alpha2 antagonist if due to alpha2 agonist
what can cause intraoperative acute blood loss?
laceration of vessel
blood-rich organs
vascularity of surgical site
what is the PCV value that is critical for oxygen delivery to tissues?
20%
when should you treat blood loss?
prior to cardiovascular effects of blood loss occur
what can you use to treat blood loss?
isotonic crystalloids
hypertonic saline
colloids
blood products
what is the blood volume of a canine?
9% x body weight (kg)
90 ml/kg
what is reflux?
passive movements of stomach contents past lower esophageal sphincter
what drugs can cause reflux/regurgitation?
opioids
what are the clinical signs of endobronchial intubation?
tachypnea
decreased SpO2
who gets laryngospasm?
cats
pigs
how can you prevent laryngospasm?
drip lidocaine onto arytenoids
avoid touching larynx
why is overinflation of the endotracheal tube cuff a problem?
pressure necrosis tracheal wall
rupture or stricture due to
can cause tube lumen to collapse inward
why can hypothermia occur?
cold hospital environment
clipping of fur
cold prep fluids
open body cavities
cooling effect of fresh gas
drug effects
why is hypothermia a problem?
peripheral vasoconstriction
decreased drug metabolism
slowed coagulation
suppression of immune system
what is hypoventilation?
insufficient CO2 is cleared by lungs
when does heart rate speed up with respiratory sinus arrhythmia?
inhalation
how can you treat second degree AV block?
anticholinergic
when should you treat ventricular tachycardia?
heart rate sustained >160-180
hemodynamically compromised
R on T
multifocal in origin
what are the causes of ventricular tachycardia?
heart disease
electrolyte imbalance
splenic disease
global hypoxemia
what are the general causes of hypotension?
low heart rate
poor cardiac contractility
vasodilation
hypovolemia
what things in anesthesia cause vasodilation?
inhalant
acepromazine
propofol
what is strength of ventricular contraction proportional to?
preload
what should you do for absolute hypovolemia under anesthesia?
decrease inhalant
crystalloid fluid bolus
replace volume loss if due to hemorrhage
what should you do for relative hypovolemia under anesthesia?
decrease inhalant
crystalloid bolus
administer alpha2 antagonist if due to alpha2 agonist
vasoconstrictive agent
an acute loss of >________ of blood volume overwhelms the compensatory mechanisms
20%
what is the blood volume of felines?
7% of body weight
70ml/kg
what is the blood volume of horses?
6-10% of body weight
60-100ml/kg
what is the dose of crystalloids for blood loss?
3 x estimated blood loss
how much does hypertonic saline increase the volume?
3-5 x volume administered
what is regurgitation?
sufficient volume to leak past upper esophageal sphincter
observed exiting mouth or nose
what are the potential consequences of regurgitation/reflux?
esophagitis
esophageal stricture
nasal and pharyngeal irritation
aspiration pneumonia
which dogs are more at risk for regurgitation/reflux?
brachycephalic dogs
laryngeal paralysis
megaesophagus
pregnancy
GI foreign body
what is endobronchial intubation?
distal tip of tube extends beyond carina into bronchus
when do 70% of anesthetic cat deaths occur?
in recovery
should you disconnect the patient for changes in recumbency?
yes
how is hypoventilation detected?
elevated ETCO2 or PaCO2
how can you treat hypoventilation?
decrease anesthetic depth
support ventilation
what patients are prone to arrhythmias under anesthesia?
brachycephalics
dachshunds
westies
what procedures are prone to causing arrhythmias under anesthesia?
enucleation
cholecystectomy
ventral slot
which drugs are prone to causing arrhythmias under anesthesia?
alpha2 agonists
ketamine
in whom is second degree AV block normal?
horses
