3.2 Respiratory, Cardiovascular, and Perfusion Status

Respiratory physiology in recovery

Anesthesia, opioids, sedatives, pain, positioning, residual neuromuscular blockade, and airway secretions can all impair ventilation after a procedure. Oxygen saturation is important, but it is a late or incomplete signal if the patient is receiving supplemental oxygen. CAPA questions often require the nurse to notice the whole respiratory pattern: respiratory rate, depth, chest movement, airway sounds, end-tidal carbon dioxide when available, mental status, and skin color.

Hypoventilation means inadequate carbon dioxide elimination and often appears as slow or shallow respirations, increasing sedation, snoring, obstruction, or rising carbon dioxide. Hypoxemia means inadequate oxygen in arterial blood and may show as low SpO2, restlessness, confusion, cyanosis, or dysrhythmias. A patient can be hypoventilating while the pulse oximeter looks acceptable if oxygen is being delivered.

Common respiratory patterns

Bronchospasm and asthma

Bronchospasm is caused by bronchial smooth muscle constriction, airway edema, and increased secretions. In an ambulatory recovery area, triggers include airway manipulation, secretions, aspiration, allergic reaction, inadequate anesthetic depth during emergence, or a reactive airway history. The patient may be anxious because they cannot move air, not simply because they are frightened.

Initial priorities are oxygenation, positioning, calling for assistance, and preparing ordered beta-2 agonist therapy such as albuterol. Listen for both wheeze and the dangerous quiet chest. A patient with severe bronchospasm may move so little air that wheezing disappears while distress worsens.

Cardiovascular physiology and perfusion

Perfusion depends on heart rate, rhythm, preload, contractility, afterload, oxygen content, and vascular tone. In PACU and ambulatory recovery, deterioration may begin as a trend: heart rate climbing, pulse pressure narrowing, skin becoming cool, mentation changing, capillary refill delaying, or drainage increasing. Waiting for a dramatic blood pressure drop misses the compensatory phase.

Hypovolemia after ambulatory procedures may result from bleeding, inadequate intake, bowel prep, third spacing, vomiting, diuresis, or vasodilation compounded by relative volume depletion. Classic early clues include tachycardia, cool clammy skin, delayed capillary refill, weak peripheral pulses, anxiety, thirst, pallor, and decreasing urine output. Blood pressure may remain near normal until compensation fails.

Shock pattern recognition

Spinal anesthesia bradycardia

Spinal anesthesia can block sympathetic fibers. If the block affects cardioaccelerator fibers, the patient may develop bradycardia and hypotension from reduced venous return and unopposed vagal tone. This can be abrupt, especially in patients who are hypovolemic or have high blocks.

The nurse should recognize the mechanism and respond quickly: assess airway and oxygenation, check blood pressure and level of block, increase surveillance, notify the anesthesia provider, and prepare ordered interventions such as fluids, vasopressors, or atropine. The key exam point is that this is not just a low heart rate. It is a perfusion problem caused by altered autonomic balance.

Postoperative hypertension

Hypertension after anesthesia is not automatically a reason to give an antihypertensive first. The nurse should look for reversible sympathetic triggers: pain, hypoxia, hypercarbia, bladder distention, shivering, anxiety, nausea, emergence excitement, fluid overload, or missed home medications. Treating the trigger often improves the pressure and protects the patient from avoidable hypotension.

Severe hypertension can threaten the surgical site, increase bleeding, strain the heart, and raise stroke risk. CAPA questions usually expect prioritization: assess the patient, compare with baseline, treat urgent oxygenation or pain problems, check the bladder if distended, notify the provider for severe or persistent elevations, and continue monitoring trends.