Maintaining a stable body temperature during surgery is essential for ensuring patient safety and optimal outcomes. Perioperative hypothermia—defined as a core body temperature below 36°C—remains a common but preventable complication that can lead to adverse effects, including increased blood loss, higher infection rates, and prolonged hospital stays. Adhering to best practices and guidelines can help surgical teams minimise these risks and maintain temperature homeostasis in patients throughout the perioperative period.
The Importance of Temperature Regulation in Surgery
Body temperature regulation is a critical physiological process, and any deviation from the norm during surgery can have significant consequences. Anaesthesia, whether general or regional, disrupts the body’s natural thermoregulatory mechanisms, making patients highly susceptible to hypothermia. Heat loss occurs through multiple pathways, including radiation, convection, conduction, and evaporation, with the operating theatre environment itself often contributing to these losses.
Impacts of Hypothermia on Surgical Outcomes
Hypothermia during surgery is associated with several adverse outcomes. Coagulation is impaired, leading to increased blood loss, while wound healing is slowed due to reduced tissue oxygenation. Hypothermia also weakens the immune response, raising the risk of postoperative infections. Furthermore, it can delay recovery by prolonging the effects of anaesthesia and increasing cardiovascular stress, particularly in vulnerable patients.
Recognising these risks, international guidelines emphasise the need for proactive measures to monitor and maintain patient temperature throughout the surgical journey.
Preoperative Measures for Temperature Management
Pre-Warming Patients Before Surgery
Pre-warming patients prior to surgery is an effective strategy for reducing the risk of perioperative hypothermia. Studies have shown that pre-warming for 30 minutes using forced-air warming systems significantly reduces core temperature drop during the initial stages of anaesthesia. This approach helps stabilise the patient’s thermal reserves, particularly for longer procedures or when large volumes of intravenous fluids are anticipated.
Risk Assessment and Patient Preparation
Identifying patients at higher risk of hypothermia is an essential step in preoperative care. Factors such as advanced age, low body weight, and certain comorbidities (e.g., diabetes or hypothyroidism) increase susceptibility to temperature loss. Tailoring temperature management strategies to the individual patient’s needs ensures a more targeted and effective approach.
Intraoperative Strategies for Maintaining Temperature
Monitoring Core Temperature
Continuous temperature monitoring is a cornerstone of intraoperative care. Core temperature can be measured using oesophageal probes, bladder thermometers, or nasopharyngeal sensors, depending on the surgical context. These methods provide accurate readings and allow real-time adjustments to warming interventions as needed.
Active Warming Techniques
Active warming methods are essential for preventing hypothermia during surgery. Forced-air warming systems, in particular, are widely regarded as the gold standard. These systems circulate warm air through a blanket placed over the patient, effectively reducing heat loss through convection.
In addition to forced-air systems, warming mattresses and circulating water garments are useful adjuncts for maintaining normothermia, especially in longer or more invasive procedures.
Intravenous Fluid Warming
The administration of large volumes of room-temperature intravenous fluids or blood products can exacerbate hypothermia. Using fluid warmers to heat these solutions to body temperature before infusion is a critical step in preventing temperature drops, particularly during surgeries with significant blood loss or fluid replacement needs.
Theatre Environment Control
The operating theatre’s ambient temperature plays a significant role in patient temperature regulation. Maintaining a warmer theatre environment—typically between 20°C and 24°C—can help minimise heat loss, especially during the initial stages of anaesthesia. While this may be uncomfortable for staff, the benefits to patient outcomes outweigh the temporary inconvenience.
Postoperative Temperature Management
Immediate Postoperative Warming
Postoperative hypothermia can delay recovery and increase the likelihood of complications. Active warming should continue in the recovery area until the patient’s core temperature is stable. Monitoring should also remain consistent to ensure that normothermia is maintained during the transition to ward care.
Patient Education and Discharge Considerations
In some cases, patients discharged on the same day as surgery may benefit from instructions on maintaining warmth at home, such as using blankets or heating pads. Ensuring that patients understand the importance of temperature management post-surgery can further reduce complications and support faster recovery.
Adhering to Guidelines and Best Practices
NICE Recommendations for Intraoperative Care
The National Institute for Health and Care Excellence (NICE) provides detailed guidance on perioperative temperature management, emphasising the importance of pre-warming, active warming during surgery, and postoperative monitoring. These recommendations form the backbone of temperature management protocols in many healthcare settings.
Multidisciplinary Collaboration
Effective temperature management requires coordination across the surgical team, anaesthetists, nurses, and operating theatre staff. Each member of the team plays a role in implementing and maintaining warming strategies, from ensuring equipment is functioning properly to monitoring temperature trends during the procedure.
Challenges and Innovations in Temperature Management
While established techniques such as forced-air warming remain highly effective, ongoing innovation in medical technology continues to improve the precision and ease of temperature management. For example, newer fluid warming devices are now more compact and efficient, making them easier to integrate into standard surgical workflows.
Nevertheless, challenges remain. In resource-limited settings, access to advanced warming devices may be constrained. In such cases, simple measures such as maintaining a warm theatre environment and minimising patient exposure can still make a significant difference.
Final Thoughts
Temperature management during surgery is a vital component of perioperative care that significantly impacts patient safety and outcomes. By adhering to established guidelines and leveraging both traditional and innovative warming techniques, healthcare professionals can minimise the risks of perioperative hypothermia and enhance recovery.
Every member of the surgical team has a role to play in maintaining normothermia, from pre-warming patients to monitoring postoperative temperature trends. With the right combination of vigilance, teamwork, and evidence-based practices, maintaining patient temperature during surgery can become a seamless part of routine care, ensuring the best possible outcomes for patients.
