10. Anesthetic Complications Flashcards
Anesthetic overdose. absolute v. relative
absolute - gave incorrect dose.
relative - right dose, but there was an underlying patient condition
signs of overdose
bradycardia, hypotension…. cardiac arrest, no pulse.
What do you do if theres an anesthetic overdose?
- get oxygen in, intubate
2. reverse any drugs
What drugs can you reverse? with what?
xylazine - yohimbine (can use atipamazole in theory)
opioids - naloxone
benzos - flumenazil (1/10 dose of dose of benzo)
dexmedetomadine - atipazole (equal volume)
NaBicarb (barbituates) overdose, what do you do?
balanced fluids! without dextrose (will swell brain) - support CV function (dopamine/dobutamine for BP, atropine/glyco for brady)
Nalve question -
phenobarbital overdose
ventilate
isoflurane put in sevoflurane vaporizor
reverse?
iso is more volatile, higher iso concentration will be delivered
Sevo has higher MAC also can go deep/into cardiac arrest quickly.
reverse? sevo in iso - pt will be light than expected
if using a rebreathing circuit you must ______ oxygen flow to reduce the amount of anesthetic being inhaled.
increase.
not necessary in nonrebreathing circuit
Tachypnea can be caused by
- **hyperthermia - opioids/other
- Equipment Malfunction (unidirectional valve stuck, soda exhausted)
- Light plane
PaCO2 is ______ when tachypnic
unpredictable
how to manage tachypnea
IPPV in just hypoventilating
check temp/equipment
Animals hyperthermic what do you do?
> 102.5
- Turn off warming devices
- COLD IV fluids
- iced gastric lavage or cold water enema
- electric fan and water spray (cats)
- increase O2 flow
- steroids if brain trauma
- NSAID if contaminated pyrogen
signs of hyperthermia
- tachypnea
2. tachycardia
causes of hyperthermia
- obese/dense hair coat - fialure to lose heat
- low flow circuit
- bair hugger/hot dog too hot/lamp OR temp
- drugs contaminated with pyrogens
- CNS injury
- hypermetabolic state (MALIGNANT HYPERTHERMIA, or bacteremia, or high T4)
signs of malignant hyperthermia
- genetic
- accumulation of Ca in muscles in hypermetabolic state.
- tachypnic, tachycardic
- acidemia high CO2 in spite of tachypnea (RESPIRATORY ACIDOSIS)
treatment of malignant hyperthermia
- stop inhalants (most common cause) maintain anesthesia with injectable - inc. O2 flow - change anesthetic machine - ***DANTRIUM reduces Ca in sarcoplasmic reticulum - ice packs/spray down - Na bicarb for acidosis - dobutamine for hypotension
hyperthermia post anesthesia is common in ____. Associated with which drugs?
cats
ketamine and hydromorphone. (But all opioids can cause hyperthermia in cats)
What to do in cat with post-op anesthesia?
- give ace
- fan and spray with water
anaphylaxis vs. anaphylactoid reaction?
anaphylaxis - Prior sensitization (IgG prod first time, second time -> anaphylaxis)
anaphylactoid - no prior sensitization (give drug -> histamine release)
common anaphylactic anesthetic drugs
- thiopental, propofol, atropine, xylazine
- opioids: morphine, meperidine
- cremophor EL (used to be used as preparation for propofol/alfaxolone)
- NMBAs: allamine/Atracurium (give slowly), procaine, ketamine,
- blood products
- abx
signs of anaphylaxis
CV: disrhythmias, HYPOTENSION
respiratory: cyanosis, labored breathing, bronchospasm
Cutaneous: hives, swollen paws
anaphylaxis:
if hypotensive, ______ the inhalant and ___drugs?___.
If bronchospasm and normotensive, _______ the inhalant.
hypotensive - turn off inhalant, give fluids and epinephrine .01mg/kg IV (IM/DC if less severe) or give diphenhydramine
keep on inhalant - its a bronchodilator
how to prevent anaphylactic reactions
- give drugs slowly (ex/ abx)
2. prophylactic diphenhydramine, corticosteroids
hypoxemia signs/numbers?
SpO2 <90% PaO2 < 60 mmHg MM: normal OR CYANOTIC bradycardia or VPCs if chronic dog may open mouth if severely hypoxemic, bc brain overrides, needs O2
When will you see cyanosis?
if Hb <5
causes of hypoxemia (5)
- Low FiO2
- Hypoventilation
- V/Q mismatch
- Shunt
- diffusion impairment
All causes of hypoxemia except ______ will respond to High FiO2
shunt
Nitrous oxide caused hypoxia?
low inspired O2 concentration, diffusion hypoxia occurs after nitrous oxide is turned off. so keep them on 100% O2 for 5 minutes after discontinuing Nitrous oxide.
hypoventilation causes hypoxemia when _____ only
breathing room air
V/Q mismatch diseases
- pneumonia, pulmonary edema, aspiration
- shunt is worst form of mismatch
- venous admixture - diaphrag hernia, bronchial obstructure
shunting of venous admixture cause ________. as hypoxemic blood passes alveoli, it doesn’t get more fresh oxygen
alveolar collapse
worst form of V/Q mismatch
***intrapulmonary shunting!!!
how to ascertain cause of hypoxemia
- look at bag
- big bag (pop off valve closed)
- no air in bag (no O2 source) - assess pulmonary compliance
- larger tidal volume to open up tidal alveoli
- PEEP if everything fails
healthy animal turned blue while under anesthesia, what are the options?
- Endobronchial intubation
- anesthetic machine malfunction pop off valve
- nitrous oxide
pop off occlusion valve
prevents people from keeping pop off closed; makes it impossible to forget to untwist valve
(Cant intubate)
what to do while waiting to set up for tracheostomy?
put needle through cricothyroid and hook up to O2 source
pulmonary edema, steps?
intubate, put on 100% O2
use peep
lasix
use inotropes if cardiogenic
steps to treat pneumonia?
100% O2
intubate, use PEEP
steps to treat bronchospasm?
100% O2
intubate, IPPV
epinephrine or aminophyllum
can suction trachea
causes of airway obstruction?
failure to remove packing in oral cavity ETT problems breathin circuit malfunction bronchospams (aspiration or allergic rxn) trauma - ruptured trachea, cervical swelling mass tracheal collapse bandage around neck to tight
paradoxical breathing indicates?
airway obstruction
known airway problem?
- preoxygenate
- minimize stress
- be prepared to intubate again in they decompensate
intubating for tracheal collapse?
have long enough tube that covers the collapse
- can intentionally ventilate one lung
succinylcholine and airway obstruction?
for muscle relaxation for complete laryngospasm in cats
lidocaine for partial laryngospasm
