A high fraction of inspired oxygen may increase mortality in intubated trauma patients - A retrospective cohort study.

BACKGROUND: Mechanical ventilation of trauma patients is common, and many will require a higher than normal fraction of inspired oxygen (FiO2) to avoid hypoxaemia. The primary objective of this study was to assess the association between FiO2 and all-cause, one-year mortality in intubated trauma patients. METHODS: Adult trauma patients intubated in the initial phase post-trauma between 2015 and 2017 were retrospectively identified. Information on FiO2 during the first 24 hours of hospitalisation and mortality was registered. For each patient the number of hours of the first 24 hours exposed to an FiO2 ≥ 80%, ≥ 60%, and ≥ 40%, respectively, were determined and categorised into exposure durations. The associations of these FiO2 exposures with mortality were evaluated using Cox regression adjusting for age, sex, body mass index (BMI), Injury Severity Score (ISS), prehospital Glasgow Coma Scale (GCS) score, and presence of thoracic injuries. RESULTS: We included 218 intubated trauma patients. The median prehospital GCS score was 6 and the median ISS was 25. One-year mortality was significantly increased when patients had received an FiO2 above 80% for 3-4 hours compared to <2 hours (hazard ratio (95% CI) 2.7 (1.3-6.0), p= 0.011). When an FiO2 above 80% had been administered for more than 4 hours, there was a trend towards a higher mortality as well, but this was not statistically significant. There was a significant, time-dependent increase in mortality for patients who had received an FiO2 ≥ 60%. There was no significant relationship observed between mortality and the duration of FiO2 ≥ 40%. CONCLUSION: A fraction of inspired oxygen above 60% for more than 2 hours during the first 24 hours of admission was associated with increased mortality in intubated trauma patients in a duration-dependent manner. However, given the limitations of this retrospective study, the findings need to be confirmed in a larger, randomized set-up.

Search and Rescue Helicopters for Emergency Medical Service Assistance: A Retrospective Study.

OBJECTIVE: The time until treatment is a crucial factor for the outcome after medical emergencies. One way of reducing transportation time is the use of helicopter-based emergency medical services, but poor weather conditions, commitment to another mission, or technical problems may limit the availability. In these cases, military search and rescue (SAR) helicopters can be used. The aim of this study was to investigate the role of SAR helicopters in the civilian emergency medical system. METHODS: We conducted a retrospective study of SAR mission reports and SAR medical records collected from the archives of the Royal Danish Air Force for the years 2016 and 2017. RESULTS: A total of 1,262 mission reports were included with a total of 628 medical records available in the study period. There were 490 of 1,246 (39.3%) missions involving patients. Interhospital transfers accounted for 306 of 604 (50.7%) of cases, whereas island evacuation constituted 110 of 604 (18.2%) cases. The most prevalent suspected diagnosis was acute coronary syndrome (14.4%). The 30-day survival rate was 87.6%. CONCLUSION: The military SAR helicopters were most commonly activated for civilian emergency medical service mission assistance due to poor weather conditions. The most frequent medical condition was acute coronary syndrome.

Measurements of Cardiac Output and Management of Blood Transfusions During Burn Surgery-An Observational Prospective Study.

Burn surgery can cause extensive bleeding, which lead to perioperative blood transfusions. The purpose of this study was to investigate whether blood transfusions during burn surgery, guided by standard monitoring with inspection of the operative field, measurements of blood pressure, heart rate, hourly diuresis, and concentrations of hemoglobin and lactate could sustain the preoperative cardiac output (CO) till end of surgery. We investigated 15 patients ≥18 years of age scheduled for burn surgery, where the perioperative monitoring included an arterial line. After induction of anesthesia and before start of surgery, we measured baseline values of CO with the minimally invasive LiDCOrapid, mean arterial pressure, and concentrations of hemoglobin and lactate in arterial blood. We measured these values every 30 minutes through surgery. The primary outcome was change in CO from baseline till end of surgery. Secondary outcomes included the change in concentrations of hemoglobin and lactate from baseline till end of surgery. We found no statistically significant change in CO from baseline till end of surgery (6.6 [±2.4] liters/min; 7.2 [±3.2] liters/min; P = .26). We found a statistically significant decrease in concentration of hemoglobin (7.2 [±0.8] mmol/liter; 6.2 [±0.9] mmol/liter; P = .0002), and a statistically significant increase in concentration of lactate (1.3 [±0.5] mmol/liter; 1.7 [±1] mmol/liter; P = .02). The perioperative blood transfusion guided by standard monitoring seemed to sustain CO from baseline till end of surgery; however, further research is needed to confirm this.

Patient experience of spinal immobilisation after trauma.

BACKGROUND: Spinal immobilisation of blunt trauma victims with potential spinal cord injury is considered standard of care. The traditional management has, however, been increasingly questioned and concerns about harm have been raised. Few studies have described the perspective of the trauma patient regarding the spinal immobilisation. The objective of this study was therefore to evaluate the patient experience of immobilisation after trauma. METHODS: We prospectively screened adult trauma patients admitted to a level 1 trauma centre for eligibility. We included adult trauma patients who had been, and remembered being, immobilised for spinal protection with a cervical collar and a spine board prehospitally or upon arrival at the trauma centre. A semi-structured interview was conducted 2 to 72 h after admission either in person or by telephone. RESULTS: One hundred and fourteen patients were eligible for inclusion based on the patient charts. Out of 98 patients assessed for participation, 48 (49%) had no memory of being immobilised. We thus included 50 patients with a median age of 37 years (IQR: 26-60) of whom 38 (76%) were men. The median injury severity score was 9 (IQR: 3-15) and the median time with a cervical collar from initial application to in-hospital removal or until the interview was given was 91 min (IQR: 72-136). Nineteen patients (38%) reported discomfort and 12 patients (24%) experienced pain related to the immobilisation. Forty patients (80%) reported a sense of protection related to the immobilisation. CONCLUSION: Discomfort related to spinal immobilisation was reported in 38% of trauma patients. However, a sense of protection was a recurring theme in 80% of the trauma patients, who recalled being immobilised. Nearly half of the awake trauma patients had no memory of being immobilised.

Restrictive vs liberal oxygen for trauma patients-the TRAUMOX1 pilot randomised clinical trial.

INTRODUCTION: Hyperoxaemia is commonly observed in trauma patients but has been associated with pulmonary complications and mortality in some patient populations. The objectives of this study were to evaluate whether maintenance of normoxia is feasible using a restrictive oxygen strategy in the initial phase after trauma and to evaluate the incidence of 30-day mortality and/or major pulmonary complications. METHODS: Forty-one adult trauma patients admitted to our trauma centre were randomised to 24 hours of restrictive oxygen therapy (no supplemental oxygen if the arterial oxyhaemoglobin saturation (SpO2 ) was at least 94%, n = 21) or liberal oxygen therapy (intubated patients: FiO2 1.0 in the trauma bay, 0.8-1.0 elsewhere; spontaneously breathing patients: 15 L/min via a non-rebreather mask, n = 20). Two blinded anaesthesiologists evaluated major in-hospital pulmonary complications within 30 days. RESULTS: Protocol compliance was high, as the median arterial oxygen tension was significantly lower in the restrictive group (10.8 kPa [9.7-12.0] vs 30.4 kPa [23.7-39.0], P < 0.0001). There were seven episodes of SpO2 below 90% in the restrictive group and one episode in the liberal group. Thirty-day mortality and/or major in-hospital pulmonary complications occurred in 4/20 (20%) in the restrictive group and in 6/18 (33%) in the liberal group: two patients in each group died within 30 days and the incidence of major in-hospital pulmonary complications was 2/20 (10%) in the restrictive group and 4/18 (22%) in the liberal group. CONCLUSION: Maintenance of normoxia using a restrictive oxygen strategy following trauma is feasible. This pilot study serves as the basis for a larger clinical trial.