Etomidate versus Ketamine as Prehospital Induction Agent in Patients with Suspected Severe Traumatic Brain Injury.

BACKGROUND: Severe traumatic brain injury is a leading cause of morbidity and mortality among young people around the world. Prehospital care focuses on the prevention and treatment of secondary brain injury and commonly includes tracheal intubation after induction of general anesthesia. The choice of induction agent in this setting is controversial. This study therefore investigated the association between the chosen induction medication etomidate versus S(+)-ketamine and the 30-day mortality in patients with severe traumatic brain injury who received prehospital airway management in the Netherlands. METHODS: This study is a retrospective analysis of the prospectively collected observational data of the Brain Injury: Prehospital Registry of Outcomes, Treatments and Epidemiology of Cerebral Trauma (BRAIN-PROTECT) cohort study. Patients with suspected severe traumatic brain injury who were transported to a participating trauma center and who received etomidate or S(+)-ketamine for prehospital induction of anesthesia for advanced airway management were included. Statistical analyses were performed with multivariable logistic regression and inverse probability of treatment weighting analysis. RESULTS: In total, 1,457 patients were eligible for analysis. No significant association between the administered induction medication and 30-day mortality was observed in unadjusted analyses (32.9% mortality for etomidate versus 33.8% mortality for S(+)-ketamine; P = 0.716; odds ratio, 1.04; 95% CI, 0.83 to 1.32; P = 0.711), as well as after adjustment for potential confounders (odds ratio, 1.08; 95% CI, 0.67 to 1.73; P = 0.765; and risk difference 0.017; 95% CI, -0.051 to 0.084; P = 0.686). Likewise, in planned subgroup analyses for patients with confirmed traumatic brain injury and patients with isolated traumatic brain injury, no significant differences were found. Consistent results were found after multiple imputations of missing data. CONCLUSIONS: The analysis found no evidence for an association between the use of etomidate or S(+)-ketamine as an anesthetic agent for intubation in patients with traumatic brain injury and mortality after 30 days in the prehospital setting, suggesting that the choice of induction agent may not influence the patient mortality rate in this population.

Prehospital Care of Severely Intoxicated Patients by a Dutch Physician-Staffed Helicopter Emergency Medical Services: A Retrospective Study.

OBJECTIVE: Intoxicated patients are often encountered by emergency medical services (eg, in cases of recreational drug use, accidental ingestion, or inhalation of toxic substances or [attempted] suicide). Earlier research showed that a physician-staffed helicopter emergency medical service (P-HEMS) is regularly dispatched for intoxicated patients. However, it is still unclear if there is added value of P-HEMS compared with standard care provided by an ambulance crew. The aim of this study was to analyze the contribution of additional expertise and equipment that P-HEMS brings to the prehospital scene. METHODS: In this retrospective study, we searched the database of the helicopter emergency medical service Lifeliner 1 serving the northwestern quadrant of the Netherlands for cases that involved intoxications from January 2013 to July 2020. Patients were included in this study if the primary reason for P-HEMS dispatch was intoxication. The types of intoxication were categorized as (illicit/recreational) drug related, suicide attempt, or accidental. The agents were categorized as stimulants, depressants, hallucinogenic, cannabinoids, and other substances such as bleach or insulin. Patient characteristics, vital signs, and the therapeutic interventions performed were recorded for analysis. RESULTS: In our study period, P-HEMS was dispatched 23,878 times. Of these dispatches, a total of 259 cases were included for further analysis. The majority of patients were male (64.5%). Sixty-six patients (25.5%) had an intoxication of depressant agents alone, whereas 60 patients (23.2%) had an intoxication with a combination of agents. With 159 (61.4%) patients, the majority of cases involved recreational drug intoxications. Unintentional intoxications were treated in 27 (10.4%) patients, whereas 73 (28.2%) cases involved suicide attempts. In 159 patients (61.4%), prehospital endotracheal intubation was required; the vast majority was performed by the helicopter emergency medical service physician. Specific antidotes were administered in 56 (21.6%) of the cases. CONCLUSION: In this study, we found that P-HEMS crews might complement usual prehospital care by ambulance crews for patients with severe intoxications by bringing advanced skills (eg, airway management and specific antidotes) to the scene.

Prehospital Intubation of Patients with Severe Traumatic Brain Injury: A Dutch Nationwide Trauma Registry Analysis.

OBJECTIVE: Patients with severe traumatic brain injury (TBI) are commonly intubated during prehospital treatment despite a lack of evidence that this is beneficial. Accumulating evidence even suggests that prehospital intubation may be hazardous, in particular when performed by inexperienced EMS clinicians. To expand the limited knowledge base, we studied the relationship between prehospital intubation and hospital mortality in patients with severe TBI in a large Dutch trauma database. We specifically hypothesized that the relationship differs depending on whether a physician-based emergency medical service (EMS) was involved in the treatment, as opposed to intubation by paramedics. METHODS: A retrospective analysis was performed using the Dutch Nationwide Trauma Registry that includes all trauma patients in the Netherlands who are admitted to any hospital with an emergency department. All patients treated for severe TBI (Head Abbreviated Injury Scale score ≥4) between January 2015 and December 2019 were selected. Multivariable logistic regression was used to assess the relationship between prehospital intubation and mortality while adjusting for potential confounders. An interaction term between prehospital intubation and the involvement of physician-based EMS was added to the model. Complete case analysis as well as multiple imputation were performed. RESULTS: 8946 patients (62% male, median age 63 years) were analyzed. The hospital mortality was 26.4%. Overall, a relationship between prehospital intubation and higher mortality was observed (complete case: OR 1.86, 95% CI 1.35-2.57, p < 0.001; multiple imputation: OR 1.92, 95% CI 1.56-2.36, p < 0.001). Adding the interaction revealed that the relationship of prehospital intubation may depend on whether physician-based EMS is involved in the treatment (complete case: p = 0.044; multiple imputation: p = 0.062). Physician-based EMS involvement attenuated but did not completely remove the detrimental association between prehospital intubation and mortality. CONCLUSION: The data do not support the common practice of prehospital intubation. The effect of prehospital intubation on mortality might depend on EMS clinician experience, and it seems prudent to involve prehospital personnel well proficient in prehospital intubation whenever intubation is potentially required. The decision to perform prehospital intubation should not merely be based on the largely unsupported dogma that it is generally needed in severe TBI, but should rather individually weigh potential benefits and harms.

Exceptional survival of an airplane stowaway, treated successfully with hyperbaric oxygen.

Survival of airplane stowaways is rare. Here we report an exceptional case of successful treatment and full recovery. After a transcontinental flight an unconscious stowaway was discovered in a wheel well of a Boeing 747-400F. Airport paramedics confirmed regular respiration and achieved 100% oxygen saturation (pulse oximetry) by high-flow oxygen. Rectal body temperature was 35.5 °C. On arrival at the emergency department, the patient's vital signs were stable. He did not respond to verbal stimuli. He localized to painful stimuli with both arms, however, there was no reaction to stimuli to both legs. We suspected his neurological deficits were caused by posthypoxic encephalopathy or altitude decompression sickness (DCS), the latter amenable to hyperbaric oxygen therapy (HBOT). HBOT was performed for 5 h (US Navy Treatment Table 6) and afterwards, full neurological recovery was documented. About 24 h after admission a new proximal paresis of the left leg was noted. Assuming recurrence of DCS, daily HBOT was scheduled for three days, after which motor function had again returned to normal. Stowaways travelling in airplane wheel wells experience extreme environmental circumstances. The presented patient survived an eight-hour exposure to calculated barometric pressures as low as 190 mmHg and ambient PO2 of 40 mmHg. Apart from creating awareness of this rare patient category, we want to stress the risk of altitude DCS in unpressurized flights. When DCS is suspected, immediate high-flow oxygen therapy should be initiated, followed by HBOT at the earliest opportunity.

Antifibrinolytics in the treatment of traumatic brain injury.

PURPOSE OF REVIEW: Traumatic brain injury (TBI) is a leading cause of trauma-related deaths, and pharmacologic interventions to limit intracranial bleeding should improve outcomes. Tranexamic acid reduces mortality in injured patients with major systemic bleeding, but the effects of antifibrinolytic drugs on outcomes after TBI are less clear. We therefore summarize recent evidence to guide clinicians on when (not) to use antifibrinolytic drugs in TBI patients. RECENT FINDINGS: Tranexamic acid is the only antifibrinolytic drug that has been studied in patients with TBI. Several recent studies failed to conclusively demonstrate a benefit on survival or neurologic outcome. A large trial with more than 12 000 patients found no significant effect of tranexamic acid on head-injury related death, all-cause mortality or disability across the overall study population, but observed benefit in patients with mild to moderate TBI. Observational evidence signals potential harm in patients with isolated severe TBI. SUMMARY: Given that the effect of tranexamic acid likely depends on a variety of factors, it is unlikely that a 'one size fits all' approach of administering antifibrinolytics to all patients will be helpful. Tranexamic acid should be strongly considered in patients with mild to moderate TBI and should be avoided in isolated severe TBI.

Thinking Out-of-the-Box: A Non-Standard Application of Standard Pulse-Oximetry and Standard Near-Infrared Spectroscopy in a COVID-19 Patient.

PURPOSE: Purpose of this report is to describe the feasibility of lingual pulse oximetry and lingual near-infrared spectroscopy (NIRS) in a COVID-19 patient to assess lingual tissue viability after several days of mechanical ventilation in the prone position. MATERIALS & METHODS: In a COVID-19 ICU-patient, the tongue became grotesquely swollen, hardened and protruding from the oral cavity after 20 h of mechanical ventilation uninterrupted in the prone position. To assess the doubtful viability of the tongue, pulse-oximetric hemoglobin O2-saturation (SpO2; Nellcor, OxiMax MAX-NI, Covidien, MA, USA) and NIRS-based, regional tissue O2-saturation measurements (rSO2; SenSmart, Nonin, MN, USA) were performed at the tongue. RESULTS: At the tongue, regular pulse-oximetric waveforms with a pulse-oximetric hemoglobin O2-saturation (SpO2) of 88% were recorded, i.e. only slightly lower than the SpO2 reading at the extremities at that time (90%). Lingual NIRS-based rSO2 measurements yielded stable tissue rSO2-values of 76-78%, i.e. values expected also in other adequately perfused and oxygenated (muscle-) tissues. CONCLUSION: Despite the alarming, clinical finding of a grotesquely swollen, rubber-hard tongue and clinical concerns on the adequacy of the tongue perfusion and oxygenation, our measurements of both arterial pulsatility (SpO2) and NIRS-based tissue oxygenation (rSO2) suggested adequate perfusion and oxygenation of the tongue, rendering non-vitality of the tongue, e.g. by lingual venous thrombosis, unlikely. To our knowledge, this is the first clinical report of lingual rSO2 measurement.

Epidemiology, Prehospital Characteristics and Outcomes of Severe Traumatic Brain Injury in The Netherlands: The BRAIN-PROTECT Study.

OBJECTIVE: A thorough understanding of the epidemiology, patient characteristics, trauma mechanisms, and current outcomes among patients with severe traumatic brain injury (TBI) is important as it may inform potential strategies to improve prehospital emergency care. The aim of this study is to describe the prehospital epidemiology, characteristics and outcome of (suspected) severe TBI in the Netherlands. METHODS: The BRAIN-PROTECT study is a prospective observational study on prehospital management of patients with severe TBI in the Netherlands. The study population comprised all consecutive patients with clinical suspicion of TBI and a prehospital GCS score ≤ 8, who were managed by one of the 4 Helicopter Emergency Medical Services (HEMS). Patients were followed-up in 9 trauma centers until 1 year after injury. Planned sub-analyses were performed for patients with "confirmed" and "isolated" TBI. RESULTS: Data from 2,589 patients, of whom 2,117 (81.8%) were transferred to a participating trauma center, were analyzed. The incidence rate of prehospitally suspected and confirmed severe TBI were 3.2 (95% CI: 3.1;3.4) and 2.7 (95% CI: 2.5;2.8) per 100,000 inhabitants per year, respectively. Median patient age was 46 years, 58.4% were involved in traffic crashes, of which 37.4% were bicycle related. 47.6% presented with an initial GCS of 3. The median time from HEMS dispatch to hospital arrival was 54 minutes. The overall 30-day mortality was 39.0% (95% CI: 36.8;41.2). CONCLUSION: This article summarizes the prehospital epidemiology, characteristics and outcome of severe TBI in the Netherlands, and highlights areas in which primary prevention and prehospital care can be improved.

Prehospital coagulation measurement by a portable blood analyzer in a helicopter emergency medical service (HEMS).

In helicopter emergency medical services, HEMS, coagulopathy presents both in trauma (e.g. consumption of coagulation factors) and non-trauma cases (e.g. anticoagulant use). Therefore, in HEMS coagulation measurements appear promising and Prothrombin Time (PT) and derived INR are attractive variables herein. We tested the feasibility of prehospital PT/INR coagulation measurements in HEMS. This study was performed at the Dutch HEMS, using a portable blood analyzer (i-Stat®1, Abbott). PT/INR measurements were performed on (hemodiluted) author's blood, and both trauma- and non-trauma HEMS patients. Device-related benefits of the i-Stat PT/INR system were portability, speed and ease of handling. Limitations included a rather narrow operational temperature range (16-30 °C). PT/INR measurements (n = 15) were performed on hemodiluted blood, and both trauma and non-trauma patients. The PT/INR results confirmed effects of hemodilution and anticoagulation, however, most measurement results were in the normal INR-range (0.9-1.2). We conclude that prehospital PT/INR measurements, although with limitations, are feasible in HEMS operations.

Face-to-Face Versus Telephonic Extended Glasgow Outcome Score Testing After Traumatic Brain Injury.

OBJECTIVE: The Extended Glasgow Outcome Scale (GOS-E) is used for objective assessment of functional outcome in traumatic brain injury (TBI). In situations where face-to-face contact is not feasible, telephonic assessment of the GOS-E might be desirable. The aim of this study is to assess the level of agreement between face-to-face and telephonic assessment of the GOS-E. SETTING: Multicenter study in 2 Dutch University Medical Centers. Inclusion was performed in the outpatient clinic (face-to-face assessment, by experienced neurologist), followed by assessment via telephone of the GOS-E after ±2 weeks (by trained researcher). PARTICIPANTS: Patients ±6 months after TBI. DESIGN: Prospective validation study. MAIN MEASURES: Interrater agreement of the GOS-E was assessed with Cohen's weighted κ. RESULTS: From May 2014 until March 2018, 50 patients were enrolled; 54% were male (mean age 49.1 years). Median time between trauma and in-person GOS-E examination was 158 days and median time between face-to-face and telephonic GOS-E was 15 days. The quadratic weighted κ was 0.79. Sensitivity analysis revealed a quadratic weighted κ of 0.77, 0.78, and 0.70 for moderate-severe, complicated mild, and uncomplicated mild TBI, respectively. CONCLUSION: No disagreements of more than 1 point on the GOS-E were observed, with the κ value representing good or substantial agreement. Assessment of the GOS-E via telephone is a valid alternative to the face-to-face interview when in-person contact is not feasible.

Comparison of videolaryngoscopy alone with video-assisted fibreoptic intubation in a difficult cadaver airway model.

ABSTRACT: No Abstract.

First, do no harm: bilateral radial artery occlusion in a COVID-19 patient.

OBJECTIVE: Objective of this case report is to draw attention to a less known thrombotic complication associated with COVID-19, i.e., thrombosis of both radial arteries, with possible (long-term) consequences. THE CASE: In our COVID-19 ICU a 49-year-old male patient was admitted, with past medical history of obesity, smoking and diabetes, but no reported atherosclerotic complications. The patient had been admitted with severe hypoxemia and multiple pulmonary emboli were CT-confirmed. ICU-treatment included mechanical ventilation and therapeutic anticoagulation. Preparing the insertion of a new radial artery catheter for invasive blood pressure measurement and blood sampling, we detected that both radial arteries were non-pulsating and occluded: (a) Sonography showed the typical anatomical localization of both radial and ulnar arteries. However, Doppler-derived flow-signals could only be obtained from the ulnar arteries. (b) To test collateral arterial supply of the hand, a pulse-oximeter was placed on the index finger. Thereafter, the ulnar artery at the wrist was compressed. This compression caused an immediate loss of the finger's pulse-oximetry perfusion signal. The effect was reversible upon release of the ulnar artery. (c) To test for collateral perfusion undetectable by pulse-oximetry, we measured regional oxygen saturation (rSO2) of the thenar muscle by near-infrared spectroscopy (NIRS). Confirming our findings above, ulnar arterial compression demonstrated that thenar rSO2 was dependent on ulnar artery flow. The described development of bilateral radial artery occlusion in a relatively young and therapeutically anticoagulated patient with no history of atherosclerosis was unexpected. CONCLUSIONS: Since COVID-19 patients are at increased risk for arterial occlusion, it appears advisable to meticulously check for adequacy of collateral (hand-) perfusion, avoiding the harm of hand ischemia if interventions (e.g., catheterizations) at the radial or ulnar artery are intended.

The P2X7 receptor tracer [11C]SMW139 as an in vivo marker of neuroinflammation in multiple sclerosis: a first-in man study.

PURPOSE: The novel PET tracer [11C]SMW139 binds with high affinity to the P2X7 receptor, which is expressed on pro-inflammatory microglia. The purposes of this first in-man study were to characterise pharmacokinetics of [11C]SMW139 in patients with active relapsing remitting multiple sclerosis (RRMS) and healthy controls (HC) and to evaluate its potential to identify in vivo neuroinflammation in RRMS. METHODS: Five RRMS patients and 5 age-matched HC underwent 90-min dynamic [11C]SMW139 PET scans, with online continuous and manual arterial sampling to generate a metabolite-corrected arterial plasma input function. Tissue time activity curves were fitted to single- and two-tissue compartment models, and the model that provided the best fits was determined using the Akaike information criterion. RESULTS: The optimal model for describing [11C]SMW139 kinetics in both RRMS and HC was a reversible two-tissue compartment model with blood volume parameter and with the dissociation rate k4 fixed to the whole-brain value. Exploratory group level comparisons demonstrated an increased volume of distribution (VT) and binding potential (BPND) in RRMS compared with HC in normal appearing brain regions. BPND in MS lesions was decreased compared with non-lesional white matter, and a further decrease was observed in gadolinium-enhancing lesions. In contrast, increased VT was observed in enhancing lesions, possibly resulting from disruption of the blood-brain barrier in active MS lesions. In addition, there was a high correlation between parameters obtained from 60- to 90-min datasets, although analyses using 60-min data led to a slight underestimation in regional VT and BPND values. CONCLUSIONS: This first in-man study demonstrated that uptake of [11C]SMW139 can be quantified with PET using BPND as a measure for specific binding in healthy controls and RRMS patients. Additional studies are warranted for further clinical evaluation of this novel neuroinflammation tracer.

Pre-hospital transfusion of red blood cells. Part 1: A scoping review of current practice and transfusion triggers.

OBJECTIVES: The primary aim of this scoping review is to describe the current use of pre-hospital transfusion of red blood cells (PHTRBC) and to evaluate criteria used to initiate PHTRBC. The effects on patients' outcomes will be reviewed in Part 2. BACKGROUND: Haemorrhage is a preventable cause of death in trauma patients, and transfusion of red blood cells is increasingly used by Emergency Medical Services (EMS) for damage control resuscitation. However, there are no guidelines and little consensus on when to initiate PHTRBC. METHODS: PubMed and Web of Science were searched through January 2019; 71 articles were included. RESULTS: Transfusion triggers vary widely and involve vital signs, clinical signs of poor tissue perfusion, point of care measurements and pre-hospital ultrasound imaging. In particular, hypotension (most often defined as systolic blood pressure ≤ 90 mmHg), tachycardia (most often defined as heart rate ≥ 120/min), clinical signs of poor perfusion (eg, prolonged capillary refill time or changes in mental status) and injury type (ie, penetrating wounds) are common pre-hospital transfusion triggers. CONCLUSIONS: PHTRBC is increasingly used by Emergency Medical Services, but guidelines on when to initiate transfusion are lacking. We identified the most commonly used transfusion criteria, and these findings may provide the basis for consensus-based pre-hospital transfusion protocols.

Pre-hospital transfusion of red blood cells. Part 2: A systematic review of treatment effects on outcomes.

The primary aim of this systematic review is to describe the effects of prehospital transfusion of red blood cells (PHTRBC) on patient outcomes. Damage control resuscitation attempts to prevent death through haemorrhage in trauma patients. In this context, transfusion of red blood cells is increasingly used by emergency medical services (EMS). However, evidence on the effects on outcomes is scarce. PubMed and Web of Science were searched through January 2019; 55 articles were included. No randomised controlled studies were identified. While several observational studies suggest an increased survival after PHTRBC, consistent evidence for beneficial effects of PHTRBC on survival was not found. PHTRBC appears to improve haemodynamic parameters, but there is no evidence that shock on arrival to hospital is averted, nor of an association with trauma induced coagulopathy or with length of stay in hospitals or intensive care units. In conclusion, PHTRBC is increasingly used by EMS, but there is no strong evidence for effects of PHTRBC on mortality. Further research with study designs that allow causal inferences is required for more conclusive evidence. The combination of PHTRBC with plasma, as well as the use of individualised transfusion criteria, may potentially show more benefits and should be thoroughly investigated in the future. The review was registered at Prospero (CRD42018084658).

Suitability and realism of the novel Fix for Life cadaver model for videolaryngoscopy and fibreoptic tracheoscopy in airway management training.

BACKGROUND: Videolaryngoscopy is increasingly advocated as the standard intubation technique, while fibreoptic intubation is broadly regarded as the 'gold standard' for difficult airways. Traditionally, the training of these techniques is on patients, though manikins, simulators and cadavers are also used, with their respective limitations. In this study, we investigated whether the novel 'Fix for Life' (F4L) cadaver model is a suitable and realistic model for the teaching of these two intubation techniques to novices in airway management. METHODS: Forty consultant anaesthetists and senior trainees were instructed to perform tracheal intubation with videolaryngoscopy and fibreoptic tracheoscopy in four F4L cadaver models. The primary outcome measure was the verbal rating scores (scale 1-10, higher scores indicate a better rating) for suitability and for realism of the F4L cadavers as training model for these techniques. Secondary outcomes included success rates of the procedures and the time to successful completion of the procedures. RESULTS: The mean verbal rating scores for suitability and realism for videolaryngoscopy was 8.3 (95% CI, 7.9-8.6) and 7.2 (95% CI, 6.7-7.6), respectively. For fibreoptic tracheoscopy, suitability was 8.2 (95% CI, 7.9-8.5) and realism 7.5 (95% CI, 7.1-7.8). In videolaryngoscopy, 100% of the procedures were successful. The mean (SD) time until successful tracheal intubation was 34.8 (30.9) s. For fibreoptic tracheoscopy, the success rate was 96.3%, with a mean time of 89.4 (80.1) s. CONCLUSIONS: We conclude that the F4L cadaver model is a suitable and realistic model to train and teach tracheal intubation with videolaryngoscopy and fibreoptic tracheoscopy to novices in airway management training.

Thinking Out of the (Big) Box: A Wearable Near-Infrared Spectroscopy Monitor for the Helicopter Emergency Medical Service.

OBJECTIVE: In prehospital helicopter emergency medical service (HEMS) settings, the medical team has limited monitoring options, usually restricted to systemic variables. Regional tissue oxygenation (rO2) can be assessed by near-infrared spectroscopy (NIRS), but clinical NIRS monitors are unpractical ("big boxes" and additional cables) in HEMS. As an alternative, we identified a wearable, athlete training NIRS device (Moxy; Idiag, Fehraltorf, Switzerland) and hypothesized that it would be applicable in our HEMS setting. METHODS: This feasibility study was performed at the Dutch HEMS Lifeliner 1. The Moxy sensor was tested in-flight and on ground. We tested various anatomic measurement spots, and multiple conditions and interventions were imposed to track rO2. RESULTS: The rO2 measurements with the wearable Moxy NIRS device are both feasible and practical in an HEMS setting. Multiple conditions and interventions were tested successfully (eg, tourniquet placement [rO2↓], muscle compression [rO2↓], reperfusion [rO2↑], oxygen administration [rO2↑], hyperemia [rO2↑], and venous congestion [rO2↓]). CONCLUSION: Our results suggest that rO2 measurements with the wearable Moxy NIRS device are both feasible and practical in HEMS, and Moxy allows the tracking of simulated pathophysiologic effects on rO2. Future studies will have to verify our preliminary data and elucidate if and how wearable NIRS monitoring may support treatment in HEMS and improve patient outcome.

Effects of post-scenario debriefing versus stop-and-go debriefing in medical simulation training on skill acquisition and learning experience: a randomized controlled trial.

BACKGROUND: Debriefing is a critical component to promote effective learning during simulation-based training. Traditionally, debriefing is provided only after the end of a scenario. A possible alternative is to debrief specific portions during an ongoing simulation session (stop-and-go debriefing). While this alternative has theoretical advantages, it is not commonly used due to concerns that interruptions disturb the fidelity and adversely affect learning. However, both approaches have not been rigorously compared, and effects on skill acquisition and learning experience are unknown. METHODS: We randomly assigned 50 medical students participating in a simulation-based cardiopulmonary resuscitation training to either a post-scenario debriefing or stop-and-go debriefing. After four weeks, participants performed a repeat scenario, and their performance was assessed using a generic performance score (primary outcome). A difference of 3 or more points was considered meaningful. A 5-item questionnaire was used to assess the subjective learning experience and the perceived stress level (secondary outcomes). RESULTS: There was no significant difference between the groups for the performance score (mean difference: -0.35, 95%CI: -2.46 to 1.77, P = 0.748, n = 48). The confidence limits excluding the specified relevant 3-point difference suggest equivalence of both techniques with respect to the primary outcome. No significant differences were observed for secondary outcomes. CONCLUSIONS: Stop-and-go debriefing does not adversely affect skill acquisition compared to the classic post-scenario debriefing strategy. This finding is reassuring when interruptions are deemed necessary and gives simulation instructors the latitude to tailor the timing of the debriefing individually, rather than adhering to the unsupported dogma that scenarios should not be interrupted. TRIAL REGISTRATION: As this study is not a clinical trial, it was not registered in a clinical trials register.

Prehospital cricothyrotomies in a helicopter emergency medical service: analysis of 19,382 dispatches.

BACKGROUND: Creating a patent airway by cricothyrotomy is the ultimate maneuver to allow oxygenation (and ventilation) of the patient. Given the rarity of airway management catastrophes necessitating cricothyrotomy, sufficiently sized prospective randomized trials are difficult to perform. Our Helicopter Emergency Medical Service (HEMS) documents all cases electronically, allowing a retrospective analysis of a larger database for all cases of prehospital cricothyrotomy. METHODS: We analyzed all 19,382 dispatches of our HEMS 'Lifeliner 1', since set-up of a searchable digital database. This HEMS operates 24/7, covering ~ 4.5 million inhabitants of The Netherlands. The potential cases were searched and cross-checked in two independent databases. RESULTS: We recorded n = 18 cases of prehospital cricothyrotomy. In all 18 cases, less invasive airway techniques, e.g., supraglottic devices, were attempted before cricothyrotomy. With exception of 2 cases, at least one attempt of orotracheal intubation had been performed before cricothyrotomy. Out of the 18 cases, 4 were performed by puncture-based technique (Melker), the remaining 14 cases by surgical technique. Indications for cricothyrotomy were diverse, dividable into 9 trauma cases and 9 medical cases. The procedure was successful in all but one case (17/18, i.e., 94%; with a 95% confidence interval of 72.7-99.9%). Outcome was such that 6/18 patients arrived at the hospital alive. Long term outcome was poor, with only 2/18 patients discharged from hospital alive. CONCLUSIONS: Cricothyrotomy remains, although rare, a regularly occurring requirement in (H)EMS. Our finding of a convincingly high success rate of 94% in trained hands encourages training and a timely performance of cricothyrotomy.

Benefits and harms of increased inspiratory oxygen concentrations.

PURPOSE OF REVIEW: The topic of perioperative hyperoxia remains controversial, with valid arguments on both the 'pro' and 'con' side. On the 'pro' side, the prevention of surgical site infections was a strong argument, leading to the recommendation of the use of hyperoxia in the guidelines of the Center for Disease Control and the WHO. On the 'con' side, the pathophysiology of hyperoxia has increasingly been acknowledged, in particular the pulmonary side effects and aggravation of ischaemia/reperfusion injuries. RECENT FINDINGS: Some 'pro' articles leading to the Center for Disease Control and WHO guidelines advocating perioperative hyperoxia have been retracted, and the recommendations were downgraded from 'strong' to 'conditional'. At the same time, evidence that supports a tailored, more restrictive use of oxygen, for example, in patients with myocardial infarction or following cardiac arrest, is accumulating. SUMMARY: The change in recommendation exemplifies that despite much work performed on the field of hyperoxia recently, evidence on either side of the argument remains weak. Outcome-based research is needed for reaching a definite recommendation.

Hemorrhage Treatment Adjuncts in a Helicopter Emergency Medical Service.

Hemorrhaging is the leading cause of preventable death after trauma. In our helicopter emergency medical service (HEMS), we introduced a bundle of 3 hemostatic adjuncts: 1) tourniquet, 2) hemostatic chitosan-based wound packings, and 3) tranexamic acid (TXA). The real-life frequency of applying these adjuncts in HEMS remains unclear. Therefore, we analyzed our electronic HEMS database regarding the use of these hemostatic adjuncts. We analyzed all subsequent dispatches of our HEMS "Lifeliner 1" within a searchable digital database (01.02.2013-22.05.2018). This HEMS operates 24/7, servicing ∼4.5 million inhabitants of the Netherlands. During the 75-month study period, we registered 15,759 dispatches, of which 8,658 were canceled, and 7,101 included on-site patient care, including 4,928 (69.4%) trauma cases. In total, we recorded 78 tourniquet applications (1.1% of patients), 104 hemostatic wound packings (1.5% of patients), and 1,379 cases with prehospital TXA administration (19.4% of patients). This difference in the use of hemostatics has several contributors, including a possible lack of awareness for tourniquets and procoagulant wound packing, a high proportion of blunt trauma with internal bleeding not accessible to tourniquet or wound packing, and a liberal use of TXA (eg, in patients with unproven hemorrhage). Besides creating awareness for those hemostatic adjuncts, the practical implications of our findings need further evaluation in future studies.