What is the best course of action for an elderly patient experiencing tremors and shaking 24 hours after anesthesia?

Tremors and Shaking 24 Hours Post-Anesthesia in Elderly Patients

This elderly patient requires immediate assessment for postoperative delirium (POD), which is the most likely diagnosis given the 24-hour timeframe, and should be evaluated using the Confusion Assessment Method (CAM) while simultaneously ruling out metabolic derangements, hypothermia, pain, and medication effects.

Immediate Diagnostic Approach

The tremors at 24 hours post-anesthesia are not typical postoperative shivering, which occurs immediately after anesthesia (within the first few hours) and is thermoregulatory in nature 1, 2. At 24 hours, you must consider:

Primary Differential Diagnosis

• Postoperative delirium (POD) - affects 15-50% of elderly surgical patients and typically manifests within 72 hours of anesthesia 3. This is the most common neurologic complication and presents with acute, fluctuating disturbances in attention, awareness, and cognition 3

• Metabolic disturbances - check electrolytes, glucose, renal function, and hepatic function immediately, as elderly patients have reduced physiological reserve and are prone to organ-specific ischemia 4

• Medication-related tremor - review all perioperative medications, particularly if benzodiazepines or opioids were used, as elderly patients have altered pharmacokinetics rendering them sensitive to relative overdose 4

• Residual hypothermia effects - verify core temperature, though this is less likely at 24 hours 4

Immediate Management Algorithm

Step 1: Assess for Delirium

• Use the CAM-ICU or standard CAM tool immediately 3
• POD is associated with threefold increase in 30-day mortality and must be identified rapidly 3
• Elderly patients are at highest risk if they are very old, frail, cognitively impaired, or have cardiovascular disease and polypharmacy 4

Step 2: Correct Precipitating Factors

• Check vital signs and oxygenation - hypoxemia and hypotension contribute to cerebral dysfunction 4
• Assess pain control - inadequate analgesia contributes to POD and should be managed with opioid-sparing multimodal analgesia 4, 3
• Review medications - discontinue any benzodiazepines or anticholinergics immediately, as these worsen delirium 3
• Optimize environment - implement orientation protocols, ensure hearing/vision aids are in place, promote sleep hygiene 3

Step 3: Laboratory Evaluation

• Complete metabolic panel including electrolytes, renal function, glucose
• Complete blood count to assess for infection or anemia
• Consider arterial blood gas if hypoxemia suspected
• Hemoglobin concentration should have been checked at end of surgery per guidelines 4

Step 4: Implement Multicomponent Prevention Bundle

Even if delirium is already present, these interventions reduce severity and duration 4, 3:

• Early mobilization
• Adequate hydration with prescribed fluid plan
• Sleep promotion (reduce nighttime interruptions)
• Cognitive stimulation and reorientation
• Optimize sensory input (glasses, hearing aids)

Pharmacological Management

If Nonpharmacological Measures Fail

• Low-dose haloperidol (0.5-1 mg) or atypical antipsychotics only when patient safety is at risk 3
• Avoid benzodiazepines - these worsen delirium except in alcohol withdrawal 3
• Do not use routine prophylactic antipsychotics - evidence does not support this approach 3

If Tremor is Isolated Without Delirium

This scenario is less likely at 24 hours but consider:

• Ensure normothermia (core temperature should have been verified at end of surgery) 4
• Optimize pain control with multimodal analgesia including paracetamol as first-line 5
• Rule out essential tremor exacerbation (though this would be pre-existing) 6

Critical Monitoring Requirements

• Continuous monitoring with Modified Early Warning Scores 4
• Critical Care Outreach team involvement if patient deteriorating 4
• If predicted perioperative mortality was >10%, this patient should have been admitted to level 2 or 3 critical care facility 4, 7, 5

Common Pitfalls to Avoid

• Do not attribute tremors to "normal postoperative shivering" at 24 hours - this is a red flag for delirium or metabolic derangement 1, 2
• Do not sedate the patient - this masks the underlying problem and worsens outcomes 3
• Do not delay assessment - POD is associated with prolonged mechanical ventilation, increased institutionalization, and long-term cognitive decline 3
• Do not overlook pain - inadequate analgesia in elderly patients contributes to delirium, cardiorespiratory complications, and failure to mobilize 4

Prognosis and Follow-up

POD increases 30-day mortality threefold and requires aggressive multimodal intervention 3. Early recognition communicated throughout the multidisciplinary team facilitates interventions aimed at reducing prevalence, severity, and duration 4. The patient requires close monitoring for at least 72 hours post-surgery, as this is the typical window for POD manifestation 3.