Prehospital interventions to prevent hypothermia in trauma patients: a scoping review

Objective: The aim of this review is to map the prehospital rewarming measures used to prevent hypothermia among trauma victims. Background: Hypothermia is responsible for an increase of the mortality and morbidity in trauma victims and its recognition and early treatment are crucial for the victim’s haemodynamic stabilisation. Prehospital interventions are particularly important, especially those that target bleeding control, haemodynamic stability, and safe body temperature. Registered nurses may be pivotal to prevention and minimisation of the dangerous effects of hypothermia. Study design and methods: A scoping review was used to identify articles from several online databases from 2010 to 2018. Studies in English, Spanish, and Portuguese were included. Two reviewers performed data extractions independently. Results: Seven studies were considered eligible for this review: two quantitative research studies, one qualitative research study, and four literature reviews. Rewarming measures can be divided into two main groups: passive rewarming, which includes the use of blankets, positioning the response unit to act as a windbreak, removing the patients’ wet clothes, drying the patient’s body, and increasing the ambient temperature; and active rewarming which includes the use of heating pads, heated oxygen, warmed intravenous fluids, peritoneal irrigation, arteriovenous rewarming, and haemodialysis. Discussion: Active measures reported by the included studies were always used as a complement to the passive measures. Active rewarming produced an increase in core temperature, and passive rewarming was responsible for intrinsic heat-generating mechanisms that will counteract heat loss. Patients receiving passive warming in addition to active warming measures presented a statistically significant increase in body core temperature as well as an improvement in the discomfort caused by cold. Conclusion: Rewarming measures seem to be essential for the prevention of hypothermia and to minimise the discomfort felt by the patient. In many countries registered nurses can play important roles in the  prehospital context of trauma victim’s assistance. Greater understanding of these roles is necessary to the development of better practices. Implications for research, policy, and practice: The findings of this study highlight that passive and active rewarming measures must be implemented as soon as possible for trauma victims. Many measures are incorporated in trauma relief protocols; however, the lack of consensus on their inclusion results in an undervaluation of this issue, which inevitably compromises the safety and wellbeing of trauma victims. In practice, supportive frameworks and an intervention plan (based on heat loss reduction and heat supply) are required to ensure that first responders including registered nurses are able to prevent and treat hypothermia. What is already known about the topic?• Hypothermia is a serious threat to trauma victims in the prehospital context and can induce a “vicious cycle” of hypothermia, acidosis, and coagulopathy.• To prevent or control the decline of a trauma patient with hypothermia, treatment of hypothermia should ideally begin in the prehospital context.• Prehospital nurses must be able to develop advanced practice competence to function effectively in their role.What this paper adds:• This paper mapped out what measures can be used by prehospital healthcare workers including nurses.• This study identified all the rewarming measures that may improve the health and wellbeing of patients with hypothermia.• The combined use of active and passive measures seems to provide better outcomes in the prevention and treatment of hypothermia in trauma victims.