Pick the Protocol
A cat is recovering after alfaxalone anesthesia. She is oxygenating normally and her blood pressure is stable, but she develops involuntary muscle jerking and marked neck/back extension. What is the most likely explanation?
Alfaxalone-associated myoclonus/opisthotonus during feline recovery.
The ECG displays a heart rate of 140 bpm, but the pulse oximeter waveform and palpable femoral pulse occur only about 90 times/min. What should concern the anesthetist?
A pulse deficit—not every electrical cardiac depolarization is producing an effective mechanical contraction/peripheral pulse.
You need IV access in an adult llama. Both sides of the neck are available.Where is the best place to insert the IV and why?
RIGHT jugular.
A dog underwent secondary closure of a large wound after a healthy granulation bed developed. The edges were mobilized successfully, but space remains beneath the reconstructed skin.
The skin edges themselves are under acceptable tension.
What postoperative complication is now being created by the repair, and what should be done about it?
The remaining dead space predisposes to seroma/fluid accumulation; dead space should be eliminated or drained.
When assessing a chronically constipated cat, a ratio comparing the maximum colon diameter to the length of this specific skeletal landmark that is a ratio around/above 1.48 is suggestive of megacolon.
L5 vertebral body
A septic dog in severe shock is induced with ketamine. The anesthetist expected HR and BP to increase, but instead myocardial contractility worsens. Why did the ketamine behave this way in this patient?
Catecholamine depletion unmasks ketamine's direct myocardial-depressant/negative-inotropic effect.
An anesthetized dog has progressively increasing EtCO₂. The capnogram has also changed from a normal square waveform to a sloped “shark-fin” appearance. SpO₂ remains acceptable on supplemental oxygen, and the vaporizer setting has not changed.
The student increases the respiratory rate on the ventilator.
What important possibility have they failed to address?
Increased airway resistance/airway obstruction rather than simple anesthetic-induced hypoventilation.
An alpaca is recovering from anesthesia and develops loud upper-airway noise with poor airflow through the nostrils. Its lungs sound clear. Why is this especially dangerous, and what should you do?
Camelids are semi-obligate nasal breathers, so nasal edema/obstruction can seriously compromise ventilation.
In an intubated patient undergoing CPR, what is the target ventilation rate and maximum recommended inspiratory time?
10 breaths per minute (1 breath every 6 seconds) with an inspiratory time of 1 second (using 100% oxygen or air).
The definitive radiographic distinction between simple gastric dilation and a full gastric dilation-volvulus (GDV) relies on identifying this anatomical compartment that is displaced dorsally and cranially.
Pylorus
An aggressive dog was chemically restrained with tiletamine-zolazepam. The procedure unexpectedly lasts longer than planned and the patient begins becoming lighter. A student suggests simply giving another full dose of tiletamine-zolazepam. What is the major concern with this plan?
Do NOT routinely redose it—the drugs can accumulate and cause prolonged/rough recovery, including seizure-like activity in dogs.
A dog has a MAP of 76 mmHg before mechanical ventilation. IPPV is started for hypercapnia. Within minutes the MAP drops to 54 mmHg; HR is unchanged and no hemorrhage is occurring. What mechanism best explains the hypotension?
Positive intrathoracic pressure decreased venous return → decreased preload → decreased cardiac output.
A horse undergoing a prolonged procedure in lateral recumbency wakes with marked muscle pain and weakness in one limb. Urine subsequently becomes dark. Neurologic deficits are not the dominant finding.
Another horse wakes with a drooping lip after prolonged pressure from a halter but is not markedly painful.
What fundamental difference separates these two complications?
First horse: post-anesthetic myopathy / muscle ischemic injury.
Second horse: compression neuropathy.
When closing the incision in small animal surgeries, what suture size is typically used for the muscle layer, and what size is used for the subcutaneous tissue layer?
2-0 (sometimes 3-0) for the muscle layer, and 3-0 (sometimes 4-0) for the subcutaneous layer.
A dog with an early joint injury has radiographic evidence of increased synovial volume. Surprisingly, the joint space looks wider, not narrower. What is the possible reason for this and how would it create this radiographic image?
Early joint disease- Effusion + synovial hyperplasia can widen the joint space early.
A middle-aged Boxer is presented for repair of a painful laceration. He is anxious but responsive. Examination suggests mild dehydration, and his PCV is below the laboratory reference interval. Cardiac auscultation is unremarkable.
The clinician is considering either acepromazine + opioid, dexmedetomidine + opioid, or a benzodiazepine + opioid.
Which general premedication strategy is most defensible in this patient?
Benzodiazepine + an appropriate opioid.
During anesthesia:
The anesthetist says, “But there is still an ECG rhythm, so the heart hasn't stopped.”
What is the correct interpretation and immediate priority?
Pulseless electrical activity — cardiac arrest despite organized electrical activity. Begin CPR/BLS.
A rabbit scheduled for a painful ocular procedure is small, anxious, and difficult to intubate. The team wants to reduce peri-anesthetic risk without compromising analgesia.
Give three separate parts of the anesthetic plan that should be modified specifically because this patient is a rabbit rather than a similarly sized cat.
-Minimal fasting / clear the mouth rather than prolonged fasting
-Anticipate difficult airway/laryngospasm and consider a rabbit supraglottic device
-Aggressively prevent hypothermia
-Closely monitor GI function/recovery.
A contaminated wound has been treated open for several days. Healthy granulation tissue is now covering the wound bed. The bandage orders call for wet-to-dry gauze because it removes bacteria and debris.
Should the plan change or stay the same?
Change. Stop the adherent wet-to-dry dressing and transition to a non-adherent/moist wound dressing.
A vomiting dog has diffusely gas- and fluid-distended small intestinal loops. It has also had severe diarrhea and an electrolyte abnormality known to impair intestinal motility.
Radiographs do not convincingly demonstrate two distinct populations of bowel.
What can this be caused by?
Functional/paralytic ileus
A highly fractious cat has symptomatic cardiac disease and must undergo a painful diagnostic procedure. Physical restraint is unsafe. One student suggests dexmedetomidine + ketamine because “that always knocks cats down really well.” Another suggests a benzodiazepine/opioid-based strategy.
Which strategy better fits the patient, and what complication should you be prepared to manage if a potent opioid-based protocol becomes very profound?
Favor the benzodiazepine + opioid approach because cardiovascular stability is the priority. Be prepared for respiratory depression/apnea and the need for intubation/IPPV
A pig initially ventilates normally after intubation. Soon afterward, oxygenation progressively worsens. Capnography confirms that the tube is in the respiratory tract and ventilation is occurring. Breath sounds are asymmetric. There has been no major change in anesthetic depth or cardiovascular status.
Before escalating drugs or ventilator pressures, what problem should be considered?
The ETT may have been advanced too far, bypassing/occluding the pig's right tracheal bronchus and compromising ventilation of the right cranial lung lobe.
Why do horses anesthetized under a triple drip protocol exhibit marked urination compared to those undergoing inhalant gas anesthesia?
Primarily the xylazine/α₂ effect: decreased ADH promotes diuresis; decreased insulin → hyperglycemia may add osmotic diuresis, while the IV triple-drip volume also contributes.
A dog with septic peritonitis requires abdominal closure. The surgeon proposes a rapidly absorbing braided material because it handles beautifully.
What are the two reasons this is a poor choice?
Wrong structure and wrong strength profile.
What ultrasound artifact is characterized by a bright white line distal to fluid-filled structures, and what artifact is characterized by a black void distal to highly reflective structures?
Distal acoustic enhancement (distal to fluid) and Distal acoustic shadowing (distal to bone/gas)