Opioids
3 major opioid receptor types
- Mu
- Kappa
- Delta
why is ET intubation beneficial
maintaining anesthesia with inhaled anesthetics
Most commonly used short-acting injectable agent
propofol
where should patients be maintained
surgical plane
when were barbiturates developed
Developed during 1930s-1950s
duration of most opioids
.5 - 3 hours
Complication if ET tube is too long (past thoracic inlet)
Intubation of one lung
general rule for IV liquids
don't inject non-clear liquids IV (propofol exception)
most common maintenance drugs
inhaled (iso or sevo)
main uses of barbiturates now
- Euthanasia (pentobarbital)
- Seizure control drugs (phenobarbital)
what do opioids cause in the cardiovascular system
Vagus-induced bradycardia
what does tracheal irritation lead to
- tracheitis
- postoperative cough
what helps with etomidate adverse effects
Premed with opioid or diazepam
typical bolus volume
1/10 to ¼ required dose for induction (given as needed)
side effects of barbiturates used in anesthesia
Transient period of apnea
why do opioids cause diarrhea
Increases segmental contractions of intestines → then GI stasis can occur
what does ET intubation stimulate
vagus nerve
Analgesia of injectable anesthetics
none
when is IM maintenance common
shelter medicine for elective sx. on cats
Bigeminy is common with barbiturates. What is it?
cardiac arrhythmia (not life-threatening in barbiturates)
How do opioids affect body temp. in dogs and cats?
- Dogs = hypothermic
- Cats = hyperthermic
patients that may be difficult to intubate
Brachycephalic dogs (Intubate quickly to prevent airway collapse)
How does Propofol protein binding work
- 95-99% of dose travels in blood bound to plasma protein
- 1-5% freely circulates
How often to apply eye lubricant during surgery
every 2-3 hours
Barbiturates in hypoproteinemic patients
Barbiturates are highly protein-bound. Use caution in these patients!