Hypothermia in critically ill trauma patients
Introduction
Hypothermia has been reported to be a valuable adjunct in cardiothoracic surgery and neurosurgery. However, in trauma patients, hypothermia has been noted to have detrimental effects with a mortality as high as 100% for temperatures below 32°C[1]. We recently noted several survivors with temperatures below this range but also noted a disturbingly high incidence at a time of year when awareness is low. We reviewed all admissions to the Surgical Intensive Care Unit (SICU) to determine which patient populations are affected most, the incidence over time, and the mortality.
Section snippets
Materials and methods
Using the SICU database, a retrospective review of all trauma patients admitted to the SICU over 41/2 years was performed. The worst temperature within the first 24 h as classified by the APACHE II score2, 3was noted. Hypothermia was defined as a temperature <35°C. Demographics including age, gender, month of admission, SICU and hospital length of stay, APACHE II score, injury severity score (ISS)[4], and mortality were noted. Statistical analysis was done using Student's t-test to compare the
Results
There were 7,045 admissions to the SICU over 41/2 years. Only 661 (9.4%) had a recorded temperature <35°C. Most of the patients (395, 59.8%) were trauma patients. Demographics of the trauma patients are shown in Table 1. Many of these patients had a neurological deficit (58, 14.6%). This represents nearly one third of all patients with a neurologic deficit admitted to the SICU during this time (29.1%). The mortality in this group of patients was 32.8%. The temperature for the trauma patients
Discussion
At least three separate studies have shown an increased risk of death with hypothermia in trauma patients1, 5, 6. When matched for injury severity, this increased mortality was independent of hypotension, fluid requirements, age, or duration of surgery[7]. The reason for this increased mortality is unclear, particularly when hypothermia has been reported to be beneficial under other circumstances. Perhaps the detrimental effects are particularly harmful in the trauma patient with a preexisting
Conclusion
The incidence of hypothermia in trauma patients is significant and is independent of the month of admission. Mortality is high but there is no threshold below which mortality is assured. Unlike historical data, 13 patients survived temperatures <32°C.
References (14)
Hypothermia and acidosis worsen coagulopathy in the patient requiring massive transfusion
Am. J. Surg.
(1990)Hypothermia in trauma victims: An ominous predictor of survival
J. Trauma
(1987)APACHE – Acute Physiology and Chronic Health Evaluation: A physiologically based classification system
Crit. Care Med.
(1981)APACHE II: A severity of disease classification system
Crit. Care Med.
(1985)The Injury Severity Score: A method for describing patients with multiple injuries and evaluating emergency care
J. Trauma
(1974)Incidence and effect of hypothermia in seriously injured patients
J. Trauma
(1987)- Psarras P. et al., Hypothermia in trauma: Incidence and prognostic significance. Presentation before the Eastern...
Cited by (37)
Preventative measures taken against hypothermia in selected Durban hospitals’ emergency centres and operating theatres
2017, African Journal of Emergency MedicineCitation Excerpt :So strong is the correlation, that a separate classification has been now developed for hypothermia in trauma patients where hypothermia is described as mild if the core temperature is below 36 °C, moderate if below 34 °C and severe if below 32 °C. Jurkovich [16] reported 100% mortality in trauma patients with admission temperatures less than 32 °C and while more recent trials [17] show some survivors, the case fatality rates remain disastrously high. It is clear, therefore, that preventing hypothermia is a priority in trauma patients.
Clinical and translational aspects of hypothermia in major trauma patients: From pathophysiology to prevention, prognosis and potential preservation
2014, InjuryCitation Excerpt :However, in civilian trauma, exposure, hypovolaemia and the infusion of cold fluids are likely the most important factors contributing to temperature loss in an injured individual. Notably, while studies have found no seasonal difference in the occurrence of hypothermia,9,22,24,25 others have found a positive association to winter time.26 Precautions should be taken during all seasons to prevent the further loss of temperature in the injured patient.
The incidence and significance of accidental hypothermia in major trauma-A prospective observational study
2011, ResuscitationCitation Excerpt :Whilst numerical cut-off points for temperature vary among authors,2,8,11,13–17 a core temperature (Tc) of <35 °C has been defined as accidental or exposure hypothermia by the American College of Surgeons Committee on Trauma12 and others.11,16,18–23 Significant physiological changes also become manifest at this temperature.9,24 For this study accidental hypothermia was defined as a Trauma Centre admission temperature of <35 °C.
Hypothermia and associated outcomes in seriously injured trauma patients in a predominantly sub-tropical climate
2009, ResuscitationCitation Excerpt :Hypothermia is an independent predictor of mortality in the trauma setting.1–4 Incidence varies, but hypothermia in the United States of America and military populations has been reported between 5 and 47%.3–10 While most studies have been conducted in cold or temperate climates,3–10 data from Queensland suggest that hypothermia in the trauma setting may occur at similar levels even in a sub-tropical, tropical or desert/grassland climate.11,12
Environmental Cold-Induced Injury
2007, Surgical Clinics of North AmericaCitation Excerpt :Both mortality rate and the incidence of hypothermia increase with higher injury severity score, massive fluid resuscitation, and the presence of shock, but controlling for these variables still demonstrates that the mortality rate of the hypothermic trauma patient is greater than that of the warm trauma patient [2,25]. Rutherford and colleagues [26] have reported that 9.4% of surgical intensive care unit patients had a core body temperature less than 35°C; the mortality rate of the hypothermic trauma patients was 53%. Compared with other patient populations, the mortality rate associated with hypothermia in the trauma victim is so high that the definition of mild, moderate, and severe hypothermia in the trauma patient warrants special classification.