Up ] Preoperative assessment ] Assessment of fitness ] Tests of respiratory, cardiac and renal disease ] Preoperative investigations ] Medical conditions ] Anaemia ] Iron deficiency ] Sickle cell anaemia ] Informed consent ] Premedication and induction ] Risk assessment ] Pharmacokinetics ] General anaesthesia ] Local anaesthesia ] Perioperative monitoring ] Enhanced recovery ] Techniques of venous access ] Perioperative injuries ] Haemostasis ] Disorders of haemostasis and coagulation ] Blood products ] [ Perioperative hypothermia ]

Perioperative hypothermia

  • Adult surgical patients are at risk of developing hypothermia at any stage of the perioperative pathway
  • Inadvertent perioperative hypothermia is a common but preventable complication of perioperative procedures
  • It is associated with poor outcomes for patients
  • Hypothermia is defined as a patient core temperature of below 36.0°C
  • During the first 30 to 40 minutes of anaesthesia, a patient’s temperature can drop to below 35.0°C
  • Reasons for this include
    • Loss of the behavioural response to cold
    • Impairment of thermoregulatory heat-preserving mechanisms under general or regional anaesthesia
    • Anaesthesia-induced peripheral vasodilatation
    • Patient getting cold while waiting for surgery on the ward or in the emergency department
  • It is important to prevent inadvertent perioperative hypothermia

Perioperative care

  •  Patients should be informed that
    • Staying warm before surgery will lower the risk of postoperative complications
    • The hospital environment may be colder than their own home
    • They should bring additional clothing, such as a dressing gown, a vest and warm clothing
    • They should tell staff if they feel cold at any time during their hospital stay
  • When using any device to measure patient temperature, healthcare professionals should
    • Be aware of, and carry out, any adjustments that need to be made in order to obtain an estimate of core temperature
    • Be aware of any such adjustments that are made automatically by the device used

Preoperative phase

  • Each patient should be assessed for their risk of inadvertent perioperative hypothermia
  • Patients should be managed as higher risk if any two of the following apply
    • ASA grade II to V
    • Preoperative temperature below 36.0°C
    • Undergoing combined general and regional anaesthesia
    • Undergoing major or intermediate surgery
    • At risk of cardiovascular complications.
  • If the patient’s temperature is below 36.0°C
    • Forced air warming should be started preoperatively on the ward or in the emergency department
    • Forced air warming should be maintained throughout the intraoperative phase

Intraoperative phase

  • The patient’s temperature should be measured and documented before induction of anaesthesia
  • It should be repeated every 30 minutes until the end of surgery
  • Induction of anaesthesia should not begin unless the patient’s temperature is 36.0°C or above 
  • Intravenous fluids (500 ml or more) and blood products should be warmed to 37°C using a fluid warming device
  • Patients who are at higher risk of inadvertent perioperative hypothermia and who are having anaesthesia for less than 30 minutes should be warmed intraoperatively from induction of anaesthesia using a forced air warming device
  • All patients who are having anaesthesia for longer than 30 minutes should be warmed intraoperatively from induction of anaesthesia using a forced air warming device

Postoperative phase

  • The patient’s temperature should be measured and documented on admission to the recovery room and then every 15 minutes.
  • Ward transfer should not be arranged unless the patient’s temperature is 36.0°C or above
  • If the patient’s temperature is below 36.0°C, they should be actively warmed using forced air warming until they are discharged from the recovery room or until they are comfortably warm

Bibliography

Forbes S S,  Eskicioglu C,  Nathens A B et al.  Evidence-based guidelines for the prevention of perioperative hypothermia.  J Am Coll Surg 2009;  209:  492-503

 

 

 
 

Copyright © 1997- 2013 Surgical-tutor.org.uk