Predictors of Hypothermia upon Trauma Center Arrival in Severe Trauma Patients Transported to Hospital via EMS

Dexmedetomidine-associated hypothermia in critical trauma: A case report and literature analysis

RATIONALE

Hypothermia, defined as a core body temperature below 35°C, is a common and serious complication in severe trauma patients, often worsened by hemorrhage and medical interventions. Dexmedetomidine, an α2-adrenergic agonist used for sedation in intensive care units, has known thermoregulatory effects; however, its association with hypothermia in trauma patients remains insufficiently explored.

PATIENT CONCERNS

A 40-year-old male with severe polytrauma from a motor vehicle accident presented in distress, with hypotension, tachycardia, and a baseline temperature of 35.8°C. Despite effective management, he developed profound hypothermia, with a recorded temperature dropping below 34.0°C after switching from midazolam to dexmedetomidine for sedation.

DIAGNOSES

The patient had multiple bilateral rib fractures, a right-sided pneumothorax, and grade 3 liver and grade 5 splenic injuries, along with orthopedic fractures. His Injury Severity Score signified critical trauma, increasing the risk of complications like hypothermia.

INTERVENTIONS

Following stabilization, dexmedetomidine was administered for sedation. Continuous warming interventions were initiated to address hypothermia; however, the temperature continued to decline. Suspecting dexmedetomidine's contribution, its administration was discontinued.

OUTCOMES

After stopping dexmedetomidine, the patient's temperature gradually recovered to 36.8°C within 5 hours. He demonstrated improved consciousness and stable vital signs, subsequently undergoing 2 successful orthopedic surgeries and discharging without further hypothermia-related issues.

LESSONS

This case highlights dexmedetomidine's potential to induce hypothermia in critically ill trauma patients. It stresses the importance of careful temperature monitoring and proactive thermoregulation during sedative administration in intensive care. Further research is needed to explore the prevalence and mechanisms of dexmedetomidine-associated hypothermia in trauma populations.

Core temperature following pre-hospital induction of anaesthesia in trauma patients

INTRODUCTION

Hypothermia is a well-recognised finding in trauma patients, which can occur even in warmer climates. It is an independent predictor of increased morbidity and mortality. It is associated with pre-hospital intubation, although the reasons for this are likely to be multifactorial. Core temperature drop after induction of anaesthesia is a well-known phenomenon in the context of elective surgery, and the mechanisms of this are well established.

METHODS

We conducted a prospective observational study to examine the behaviour of core temperature in patients undergoing pre-hospital anaesthesia for traumatic injuries.

RESULTS

Between 2017 and 2021 data were collected on 48 patients. The data from 40 of these were included in the final analysis.

DISCUSSION

Our data do not show a decrease in the core temperatures of patients who receive pre-hospital anaesthesia, unlike patients who are anaesthetised without pre-warming, in operating theatres. The lack of a change could relate to patient, anaesthetic or environmental factors.

Changes in temperature in preheated crystalloids at ambient temperatures relevant to a prehospital setting: an experimental simulation study with the application of prehospital treatment of trauma patients suffering from accidental hypothermia

BACKGROUND

Accidental hypothermia is common in all trauma patients and contributes to the lethal diamond, increasing both morbidity and mortality. In hypotensive shock, fluid resuscitation is recommended using fluids with a temperature of 37-42°, as fluid temperature can decrease the patient's body temperature. In Sweden, virtually all prehospital services use preheated fluids. The aim of the present study was to investigate how the temperature of preheated infusion fluids is affected by the ambient temperatures and flow rates relevant for prehospital emergency care.

METHODS

In this experimental simulation study, temperature changes in crystalloids preheated to 39 °C were evaluated. The fluid temperature changes were measured both in the infusion bag and at the patient end of the infusion system. Measurements were conducted in conditions relevant to prehospital emergency care, with ambient temperatures varying between - 4 and 28 °C and flow rates of 1000 ml/h and 6000 ml/h, through an uninsulated infusion set at a length of 175 cm.

RESULTS

The flow rate and ambient temperature affected the temperature in the infusion fluid both in the infusion bag and at the patient end of the system. A lower ambient temperature and lower flow rate were both associated with a greater temperature loss in the infusion fluid.

CONCLUSION

This study shows that both a high infusion rate and a high ambient temperature are needed if an infusion fluid preheated to 39 °C is to remain above 37 °C when it reaches the patient using a 175-cm-long uninsulated infusion set. It is apparent that the lower the ambient temperature, the higher the flow rate needs to be to limit temperature loss of the fluid.

Mechanism matters: mortality and endothelial cell damage marker differences between blunt and penetrating traumatic injuries across three prehospital clinical trials

Injury mechanism is an important consideration when conducting clinical trials in trauma. Mechanisms of injury may be associated with differences in mortality risk and immune response to injury, impacting the potential success of the trial. We sought to characterize clinical and endothelial cell damage marker differences across blunt and penetrating injured patients enrolled in three large, prehospital randomized trials which focused on hemorrhagic shock. In this secondary analysis, patients with systolic blood pressure < 70 or systolic blood pressure < 90 and heart rate > 108 were included. In addition, patients with both blunt and penetrating injuries were excluded. The primary outcome was 30-day mortality. Mortality was characterized using Kaplan-Meier and Cox proportional-hazards models. Generalized linear models were used to compare biomarkers. Chi squared tests and Wilcoxon rank-sum were used to compare secondary outcomes. We characterized data of 696 enrolled patients that met all secondary analysis inclusion criteria. Blunt injured patients had significantly greater 24-h (18.6% vs. 10.7%, log rank p = 0.048) and 30-day mortality rates (29.7% vs. 14.0%, log rank p = 0.001) relative to penetrating injured patients with a different time course. After adjusting for confounders, blunt mechanism of injury was independently predictive of mortality at 30-days (HR 1.84, 95% CI 1.06-3.20, p = 0.029), but not 24-h (HR 1.65, 95% CI 0.86-3.18, p = 0.133). Elevated admission levels of endothelial cell damage markers, VEGF, syndecan-1, TM, S100A10, suPAR and HcDNA were associated with blunt mechanism of injury. Although there was no difference in multiple organ failure (MOF) rates across injury mechanism (48.4% vs. 42.98%, p = 0.275), blunt injured patients had higher Denver MOF score (p < 0.01). The significant increase in 30-day mortality and endothelial cell damage markers in blunt injury relative to penetrating injured patients highlights the importance of considering mechanism of injury within the inclusion and exclusion criteria of future clinical trials.

RETRACTED: Etiological characteristics of wound infection in severe trauma patients and logistic regression analysis of influencing factors of infection

To investigate the etiological characteristics of wound infection in severe trauma patients and logistic regression analysis of the influencing factors of infection. The 116 patients with severe trauma who were intervened in our hospital from 22 October 2017 to 9 September 2019 were selected as the subjects of this retrospective study and divided into a control group and an observation group according to whether they were infected or not, 58 cases each. Observe and compare the pathogenic characteristics (pathogen distribution and drug resistance) of the two groups of patients and logistic regression analysis of the influencing factors of infection. The gram-positive bacteria in the observation group were mainly Staphylococcus aureus, accounting for 17.20%; the fungi were mainly Candida tropicalis, accounting for 17.20%; and the gram-negative bacteria were mainly Acinetobacter baumannii, accounting for 20.39%; the control group was gram-positive. The main bacteria are S. aureus, accounting for 8.60%; the fungi are mainly Candida albicans, accounting for 4.3%; and the gram-negative bacteria, which are mainly Pseudomonas aeruginosa, accounting for 14.56%. Gram-positive bacteria Enterococcus faecium, S. aureus, Enterococcus faecalis, Staphylococcus epidermidis. The highest drug resistance of other gram-positive bacteria is penicillin and erythromycin at 85.00% and above. Fungi C. tropicalis, Candida parapsilosis, C. albicans, fluconazole and amphotericin B have the highest resistance to 80.00% and above. Gram-negative bacteria A. baumannii, Ps. aeruginosa, Klebsiella pneumoniae, Escherichia coli, Proteus mirabilis, Enterobacter cloacae and other gram-negative bacteria are the most resistant to ampicillin, and Piperacillin was 70.00% and above. The combined primary diseases of the two groups of patients, ventilator use ≧3 days, long-term use of glucocorticoids, catheter use days ≧5 days, fever days ≧3 days and long-term use of broad-spectrum antimicrobial drugs, the difference is statistically significant academic significance (p < 0.05). Logistic analysis showed that combined with underlying diseases, fever days ≥3 days, long-term use of glucocorticoids and catheter use days ≥5 days are the influencing factors for the occurrence of wound infections in patients with severe trauma. Trauma patients are prone to wound infections, and there are many influencing factors. Close observation of patients should be strengthened. Effective prevention and control measures should be taken for related influencing factors to reduce the incidence of infection.

Impact of accidental hypothermia in trauma patients: A retrospective cohort study

BACKGROUND

Trauma patients with hypothermia have substantial increases in mortality and morbidity. In severely injured patients, hypothermia is common with a rate up to 50% in various geographic areas. This study aims to elucidate the incidence, predictors, and impact of hypothermia on outcomes in severely injured patients.

METHODS

This was a retrospective cohort study which included trauma patients with an Injury Severity Score (ISS) ≥ 16 admitted to a level 1 trauma center in the Netherlands between January 1, 2015 and December 31, 2021. Primary outcome was incidence of hypothermia on arrival at the emergency department. Factors associated with hypothermia were identified. Secondary outcomes were transfusion requirement, mortality, and intensive care unit (ICU) admission. Logistic regression analysis was used to identify associations.

RESULTS

A total of 2032 severely injured patients were included of which 257 (12.6%) were hypothermic on hospital arrival. Predictors for hypothermia on hospital arrival included higher ISS, prehospital intubation, cervical spine immobilization, winter months, systolic blood pressure (SBP) < 90 mmHg and Glasgow Coma Scale (GCS) ≤ 8. Hypothermia was independently associated with transfusion requirement (OR, 2.68; 95% CI, 1.94 - 3.73; p < 0.001), mortality (OR, 2.12; 95% CI, 1.40 - 3.19; p < 0.001) and more often ICU admission (OR, 1.81; 95% CI, 1.10 - 2.97, p = 0.019).

CONCLUSIONS

In this study, hypothermia was present in 12.6% of severely injured patients. Hypothermia was associated with increased transfusion requirement, mortality, and ICU admission. Identified predictors for hypothermia included the severity of injury, intubation, and immobilization, as well as winter season, SBP < 90 mmHg, and GCS ≤ 8.

Hypothermia: Beyond the Narrative Review-The Point of View of Emergency Physicians and Medico-Legal Considerations

Hypothermia is a widespread condition all over the world, with a high risk of mortality in pre-hospital and in-hospital settings when it is not promptly and adequately treated. In this review, we aim to describe the main specificities of the diagnosis and treatment of hypothermia through consideration of the physiological changes that occur in hypothermic patients. Hypothermia can occur due to unfavorable environmental conditions as well as internal causes, such as pathological states that result in reduced heat production, increased heat loss or ineffectiveness of the thermal regulation system. The consequences of hypothermia affect several systems in the body-the cardiovascular system, the central and peripheral nervous systems, the respiratory system, the endocrine system and the gastrointestinal system-but also kidney function, electrolyte balance and coagulation. Once hypothermia is recognized, prompt treatment, focused on restoring body temperature and supporting vital functions, is fundamental in order to avert preventable death. It is important to also denote the fact that CPR has specificities related to the unique profile of hypothermic patients.

Prehospital Active and Passive Warming in Trauma Patients

OBJECTIVE

Hypothermia is common among trauma patients and can lead to a serious rise in morbidity and mortality. This study was performed to investigate the effect of active and passive warming measures implemented in the prehospital phase on the body temperature of trauma patients.

METHODS

In a multicenter, multinational prospective observational design, the effect of active and passive warming measures on the incidence of hypothermia was investigated. Adult trauma patients who were transported by helicopter emergency medical services (HEMS) or ground emergency medical services with an HEMS physician directly from the scene of injury were included. Four HEMS/ground emergency medical services programs from Canada, the United States, and the Netherlands participated.

RESULTS

A total of 80 patients (n = 20 per site) were included. Eleven percent had hypothermia on presentation, and the initial evaluation occurred predominantly within 60 minutes after injury. In-line fluid warmers and blankets were the most frequently used active and passive warming measures, respectively. Independent risk factors for a negative change in body temperature were transportation by ground ambulance (odds ratio = 3.20; 95% confidence interval, 1.06-11.49; P = .03) and being wet on initial presentation (odds ratio = 3.64; 95% confidence interval, 0.99-13.36; P = .05).

CONCLUSION

For adult patients transported from the scene of injury to a trauma center, active and passive warming measures, most notably the removal of wet clothing, were associated with a favorable outcome, whereas wet patients and ground ambulance transport were associated with an unfavorable outcome with respect to temperature.

Traumatisme et température

Le patient traumatisé est exposé à l’hypothermie. La mortalité des traumatisés hypothermes est multipliée par quatre ou cinq. Les interactions de l’hypothermie avec l’hémostase et le système cardiovasculaire sont délétères. Les effets sur la coagulation sont multiples et concourent directement à la surmortalité faisant de l’hypothermie une composante majeure de la « triade létale ». Les causes d’hypothermie chez le patient traumatisé sont multiples : 1) environnementales, le risque augmente quand la température ambiante diminue ; 2) cliniques, le risque augmente avec la gravité ; et aussi 3) thérapeutiques, par exemple par la perfusion de solutés à température ambiante. Une prise en charge optimale repose sur une mesure précoce et un monitorage continu de la température corporelle. L’objectif thérapeutique est de maintenir une température corporelle au moins égale à 36 °C. Limiter le déshabillage du patient, le protéger du froid avec une couverture de survie, l’installer rapidement dans une ambulance chauffée, recourir à des dispositifs de réchauffement actifs, perfuser des solutés réchauffés sont les éléments fondamentaux de la prise en charge d’un patient traumatisé, potentiellement hypotherme.

Application of the Whole Optimization of Emergency Nursing Model United and Its Influence on Patients' Stress Response and Nursing Satisfaction

Objective

To investigate the use of an integrated emergency nursing model with a multidisciplinary team (MDT) teaching method for practice of nursing towards multiple trauma in the emergency department and its influence on patients' stress response and nursing satisfaction.

Methods

The research subjects were 120 multiple trauma patients hospitalized to our hospital's emergency department between January 2019 and January 2020, who were evenly divided into groups A (n = 60) and B (n = 60) based on the sequence of admission. For patients in group A, on the basis of whole optimization of the emergency nursing model, the MDT teaching and training were given to the nursing staff in group A. Patients in group B had their emergency nursing model completely optimized. The assessment scores of nursing staff were compared. The patients' C-reactive protein (CRP) levels in peripheral circulation, first-aid time indices, treatment effect, risk of complications & nursing contentment were all investigated.

Results

Nursing personnel in group A had considerably higher achievement scores than staff nurses in group B (P < 0.001). CRP levels in group A were considerably lower following therapy (P < 0.05) than those in group B. The time it took for group A to receive first assistance was considerably less than that for group B (P < 0.001). Group A had a considerably superior treatment effect than group B (P < 0.05). Complications occurred at a lower rate in group A (P < 0.05) than in group B. Group A nurses were more satisfied than group B nurses (P < 0.05).

Conclusion

The entire optimization of the emergency nursing model combined with the MDT way of teaching can abbreviate the rescue process, reduce stress, improve treatment effect & reduce the possibility of complications in multiple trauma patients in the emergency department, and patients seem to be more comfortable with this nursing model. As a result, it should become more well known.

Influencing Factors and Prevention of Sepsis or Acute Kidney Injury in 85 Patients with Severe Trauma

Severe trauma can cause systemic reactions, leading to massive bleeding, shock, asphyxia, and disturbance of consciousness. At the same time, patients with severe trauma are at high risk of sepsis and acute renal injury. The occurrence of complications will increase the difficulty of clinical treatment, improve the mortality rate, and bring heavy physical and mental burdens and economic pressure to patients and their families. It is of great clinical significance to understand the high risk factors of sepsis and AKI and actively formulate prevention and treatment measures. In this study, the clinical data of 85 patients with severe trauma were analyzed by univariate and multivariate logistic regression to identify the risk factors leading to sepsis or AKI and analyze the prevention and treatment strategies. The results showed that multiple injuries, APACHE II score on admission, SOFA score on admission, and mechanical ventilation were independent influencing factors of sepsis in patients with severe trauma, while hemorrhagic shock, APACHE II score on admission, CRRT, and sepsis were independent influencing factors of AKI in patients with severe trauma. Severe trauma patients complicated with sepsis or AKI will increase the risk of death. In the course of treatment, prevention and intervention should be given as far as possible to reduce the incidence of complications.

A simple improvised prehospital method to warm intravenous fluid

STUDY OBJECTIVE

Use of warmed intravenous fluid by emergency medical services (EMS) for prehospital injured patients is recommended to avoid iatrogenic hypothermia. We hypothesized that an improvised heating method would significantly increase the temperature of an intravenous fluid bag in a simulated prehospital environment.

METHODS

The change from baseline in the temperature of a 1-L intravenous fluid bag positioned above the vehicle windshield defroster vent was measured for 30 minutes using a thermocouple probe. Temperature changes were compared with a control fluid bag positioned on the vehicle console armrest. A total of 10 independent experiments were performed.

RESULTS

The defroster vent method increased intravenous fluid bag temperature from a mean starting temperature of 19.4°C (95% confidence interval [CI], 17.4°C-21.4°C) to a mean end temperature of 32.6°C (95% CI, 30.6°C-34.6°C) after 30 minutes. The temperature of a control intravenous fluid bag (mean starting temperature of 20.1°C; 95% CI, 19.0°C-21.2°C) exposed to a warmed (mean 33.2°C) passenger compartment changed little during the same time period (mean end temperature of 22.3°C; 95% CI, 19.4°C-25.2°C).

CONCLUSIONS

Convective warming of an intravenous fluid bag using the dashboard defroster vent significantly raised the fluid temperature. Such a method should be readily available to EMS or first responders.

Hypothermia in Trauma

Hypothermia in trauma patients is a common condition. It is aggravated by traumatic hemorrhage, which leads to hypovolemic shock. This hypovolemic shock results in a lethal triad of hypothermia, coagulopathy, and acidosis, leading to ongoing bleeding. Additionally, hypothermia in trauma patients can deepen through environmental exposure on the scene or during transport and medical procedures such as infusions and airway management. This vicious circle has a detrimental effect on the outcome of major trauma patients. This narrative review describes the main factors to consider in the co-existing condition of trauma and hypothermia from a prehospital and emergency medical perspective. Early prehospital recognition and staging of hypothermia are crucial to triage to proper care to improve survival. Treatment of hypothermia should start in an early stage, especially the prevention of further cooling in the prehospital setting and during the primary assessment. On the one hand, active rewarming is the treatment of choice of hypothermia-induced coagulation disorder in trauma patients; on the other hand, accidental or clinically induced hypothermia might improve outcomes by protecting against the effects of hypoperfusion and hypoxic injury in selected cases such as patients suffering from traumatic brain injury (TBI) or traumatic cardiac arrest.

Comparison of Electric Resistive Heating Pads and Forced-Air Warming for Pre-hospital Warming of Non-shivering Hypothermic Subjects

INTRODUCTION

Victims of severe hypothermia require external rewarming, as self-rewarming through shivering heat production is either minimal or absent. The US Military commonly uses forced-air warming in field hospitals, but these systems require significant power (600-800 W) and are not portable. This study compared the rewarming effectiveness of an electric resistive heating pad system (requiring 80 W) to forced-air rewarming on cold subjects in whom shivering was pharmacologically inhibited.

MATERIALS AND METHODS

Shivering was inhibited by intravenous meperidine (1.5 mg/kg), administered during the last 10 min of cold-water immersion. Subjects then exited from the cold water, were dried and lay on a rescue bag for 120 min in one of the following conditions: spontaneous rewarming only (rescue bag closed); electric resistive heating pads (EHP) wrapped from the anterior to posterior torso (rescue bag closed); or, forced-air warming (FAW) over the anterior surface of the body (rescue bag left open and cotton blanket draped over warming blanket). Supplemental meperidine (to a maximum cumulative dose of 3.3 mg/kg) was administered as required during rewarming to suppress shivering.

RESULTS

Six healthy subjects (3 m, 3 f) were cooled on three different occasions, each in 8°C water to an average nadir core temperature of 34.4 ± 0.6°C (including afterdrop). There were no significant differences between core rewarming rates (spontaneous; 0.6 ± 0.3, FAW; 0.7 ± 0.2, RHP; 0.6 ± 0.2°C/h) or post-cooling afterdrop (spontaneous; 1.9 ± 0.4, FAW; 1.9 ± 0.3, RHP; 1.6 ± 0.2°C) in any of the 3 conditions. There were also no significant differences between metabolic heat production (S; 74 ± 20, FAW; 66 ± 12, RHP; 63 ± 9 W). Total heat gain was greater with FAW (36 W gain) than EHP (13 W gain) and spontaneous (13 W loss) warming (p < 0.005).

CONCLUSIONS

Total heat gain was greater in FAW than both EHP, and spontaneous rewarming conditions, however, there were no observed differences found in rewarming rates, post-cooling afterdrop or metabolic heat production. The electric heat pad system provided similar rewarming performance to a forced-air warming system commonly used in US military field hospitals for hypothermic patients. A battery-powered version of this system would not only relieve pressure on the field hospital power supply but could also potentially allow extending use to locations closer to the field of operations and during transport. Such a system could be studied in larger groups in prospective trials on colder patients.