EtCO₂ Waveforms
You see a capnogram with no waveform at all during expiration. What’s your first step?
What is check ET tube for disconnection, blockage, or apnea?
This ECG rhythm is normal and has regular P waves followed by QRS complexes.
What is normal sinus rhythm?
The patient has a blink reflex and responds to toe pinch. What’s your action?
What is increase anesthetic depth or give additional sedative?
A dog is vocalizing and paddling after anesthesia. You give naloxone, and it gets worse. Why?
What is the patient was painful, not dysphoric?
EtCO₂ drops to 15 mmHg suddenly during anesthesia. What do you do first?
What is check the patient’s pulse and perfusion?
If the baseline EtCO₂ does not return to zero, what’s a possible equipment-related cause?
What is CO₂ rebreathing due to exhausted soda lime or valve malfunction?
You see P waves with intermittent dropped QRS complexes; the PR interval is constant.
What is 2nd degree AV block, Mobitz type II?
A dog's eyes are ventromedial with a weak palpebral reflex and strong jaw tone. What stage is this?
What is light surgical plane (Stage III Plane 1)?
After alfaxalone induction, a cat thrashes during recovery. What’s the most likely cause?
What is excitation from alfaxalone without adequate pre-med or analgesia?
ECG shows VPCs, and EtCO₂ is climbing to 63 mmHg. What’s your first action?
What is increase manual ventilation and evaluate oxygenation?
A capnogram with a gradual “shark-fin” upstroke likely indicates this airway issue.
What is partial obstruction or bronchospasm?
The ECG shows wide, bizarre early QRS complexes not preceded by P waves.
What are ventricular premature complexes (VPCs)?
A cat has no palpebral reflex, central eyes, and weak corneal reflex. What’s your concern?
What is anesthetic depth may be too deep?
You reversed dexmedetomidine with atipamezole and the dog is anxious and panting. What might help?
What is re-administering a small sedative dose or giving additional analgesia?
HR on ECG is 45 bpm in a dog; EtCO₂ is rising and mucous membranes are pale. What drug might help?
What is atropine?
This phase of the capnogram, called Phase 0, drops steeply to baseline and represents this part of breathing.
What is inspiration?
P waves are present, but not followed by QRS complexes at all; atria and ventricles beat independently.
What is 3rd degree AV block (complete block)?
Jaw tone is completely absent, heart rate is dropping, and breathing is shallow. What do you do?
What is reduce inhalant, ventilate, and support perfusion?
Midazolam was reversed with flumazenil. The patient now has tremors and is anxious. What did you miss?
What is underlying pain or inadequate sedation?
EtCO₂ is normal but the patient’s pulse oximeter is reading 83%. What’s happening?
What is hypoxemia; increase oxygen, check probe and perfusion?
This condition causes progressive increases in the height of the EtCO₂ waveform over time.
What is hypoventilation?
This rhythm is fast, irregular, and has no identifiable P waves.
What is atrial fibrillation?
In a healthy dog, what three reflexes are best for determining surgical anesthesia?
What are palpebral, pedal (toe pinch), and eye position?
A geriatric cat recovering from anesthesia is agitated, hissing, paddling, and uncoordinated. No opioids were used. Pre-med included midazolam and alfaxalone. HR is 160, RR is 40, and SpO₂ is 97%. You suspect paradoxical excitement from the sedative. What reversal agent might help?
What is flumazenil?
ECG shows 3rd degree AV block in a patient with no palpable pulses. What is the emergency protocol?
What is begin CPR, give epinephrine, and prepare for emergency pacing?