What are the causes of postoperative shivering on day 2?

Causes of Post-Operative Shivering on Day 2

The primary causes of postoperative shivering on day 2 are hypothermia, pain, infection (particularly with fever), and medication withdrawal effects, with hypothermia being the most common cause that should be addressed first through active warming measures. 1

Common Causes of Postoperative Shivering

1. Hypothermia

• Hypothermia is the most common cause of postoperative shivering, which can persist beyond the immediate recovery period 1
• Patients may experience delayed hypothermia due to redistribution of heat from the core to the periphery even on day 2 1
• Inadequate thermal management during the perioperative period can lead to persistent temperature dysregulation 1

2. Pain and Inflammatory Response

• Postoperative pain can trigger shivering through cytokine release and stress response 2
• Surgical procedures release cytokines that can cause non-thermoregulatory shivering even in normothermic patients 2
• Inadequate pain control on day 2 may manifest as shivering 1

3. Infection

• Early infection can present with temperature spikes and associated shivering 1
• Respiratory and wound infections are common causes of shivering on day 2 1
• A spike in temperature with shivering may be an early sign of infection requiring prompt evaluation 1

4. Medication-Related Causes

• Acute opioid withdrawal, especially from short-acting narcotics used during surgery 3
• Reduction in sedative medications that were suppressing shivering response 1
• Medication interactions affecting thermoregulatory control 1

Risk Factors for Postoperative Shivering

• Young age (strongest independent risk factor) 4
• Endoprosthetic surgery 4
• Core hypothermia during the perioperative period 4
• Inadequate intraoperative warming 1
• Prolonged surgical exposure 1

Evaluation of Postoperative Shivering on Day 2

• Measure core temperature to differentiate between hypothermic and normothermic shivering 1
• Assess for signs of infection (check wound sites, respiratory status, urinary tract) 1
• Review pain management and recent changes in medication regimens 2
• Evaluate intravenous cannula sites for phlebitis (redness, swelling) 1
• Check for symptoms of sepsis if temperature ≥ 38.0°C 1

Management Approach

For Hypothermia-Related Shivering:

• Implement active warming with forced-air warming devices 1
• Ensure normothermia is maintained through appropriate ambient temperature 1
• Use warmed intravenous fluids if needed 1

For Pain-Related Shivering:

• Optimize analgesic regimen with appropriate multimodal analgesia 2
• Consider NSAIDs if not contraindicated 1
• Ensure regular rather than as-needed pain medication administration 1

For Infection-Related Shivering:

• Obtain blood cultures if fever is present 1
• Initiate appropriate antibiotics if infection is suspected 1
• Provide supportive care including hydration and oxygenation 1

Pharmacological Management:

• Meperidine (25-50mg) is the most effective medication for treating established shivering 1
• Dexamethasone has shown efficacy in preventing postoperative shivering 5
• Dexmedetomidine may be effective for prevention of shivering in selected cases 6

Prevention Strategies for High-Risk Patients

• Maintain perioperative normothermia through active warming 1
• Adequate hydration throughout the perioperative period 1
• Appropriate pain management with scheduled analgesics 2
• Consider prophylactic medications in high-risk patients 4
• Monitor for early signs of infection and treat promptly 1

Special Considerations

• Patients with sickle cell disease require particular attention to prevent shivering as it can lead to sickling crisis 1
• Elderly patients and those with cardiac disease are at higher risk for complications from shivering due to increased oxygen consumption 3
• Patients who have undergone neuraxial anesthesia may experience delayed shivering on day 2 as the block wears off 1