Fat intravasation, fat emboli and fat embolism syndrome in adult major trauma patients with intraosseous catheters: a systematic review.

INTRODUCTION: Intraosseous (IO) administration of medication, fluids and blood products is accepted practice for critically injured patients in whom intravenous access is not immediately available. However, there are concerns that high intramedullary pressures resulting from IO infusion may cause bone marrow intravasation and subsequent fat embolisation. The aim of this systematic review is to synthesise the existing evidence describing fat intravasation, fat embolism and fat embolism syndrome (FES) following IO infusion. METHODS: A systematic search of CINAHL, MEDLINE and Embase was undertaken using the search terms "intraosseous", "fat embolism", "fat intravasation" and "fat embolism syndrome". Two authors independently screened abstracts and full texts, against eligibility criteria and assessed risk of bias. A grey literature search (including references) was undertaken. Inclusion criteria were: all human and animal studies reporting novel data on IO-associated fat emboli. This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis. RESULTS: 22 papers were identified from the search, with a further 5 found from reference lists. N=7 full papers met inclusion criteria. These papers were all translational animal studies. The overall risk of bias was high. Studies demonstrated that fat intravasation and fat embolisation are near universal after IO infusion, but of uncertain clinical significance. The initial IO flush appears to cause the highest intramedullary pressure and highest chance of fat intravasation and embolisation. No conclusions could be drawn on FES. CONCLUSIONS: IO catheters remain a useful intervention in the armamentarium of trauma clinicians. Although their use is widely accepted, there is a paucity of evidence investigating fat embolisation in IO infusions. Despite this, pulmonary fat emboli after IO infusion are very common. The existing data are of low quality with a high risk of bias. More research is needed to address this important subject. PROSPERO REGISTRATION NUMBER: CRD42023399333.

Red cell haemolysis secondary to intraosseous (IO) blood transfusion in adult patients with major trauma: a systematic review.

INTRODUCTION: Intraosseous (IO) administration of medications and blood products is accepted practice in major trauma when intravenous access is not immediately available. However, there is a concern that the high infusion pressures required for IO transfusion may increase the risk of red cell haemolysis and its associated complications. The aim of this systematic review is to synthesise the existing evidence describing the risks of red cell haemolysis in IO blood transfusion. METHODS: We undertook a systematic search of MEDLINE, CINAHL and EMBASE using the search terms: "intraosseous transfusion" and "haemolysis". Two authors independently screened abstracts, and reviewed full-text articles against the inclusion criteria. Reference lists of included studies were reviewed and a grey literature search undertaken. Studies were assessed for risk of bias. Inclusion criteria were: all human and animal study types that reported novel data on IO-associated red cell haemolysis. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline was used. RESULTS: Twenty-three abstracts were identified; n=9 full papers met the inclusion criteria. No further studies were identified from reference lists or grey literature. These papers included: seven large animal translational studies, a prospective and a retrospective human study. The overall risk of bias was high. One animal study with good translatability to adult patients with trauma demonstrated haemolysis. Other animal studies had methodological constraints that limit their human applicability. No haemolysis was observed in low-density flat bones (sternum), whereas haemolysis was reported in long bones (humerus, tibia). IO infusion using a three-way tap was associated with haemolysis. Conversely, pressure bag transfusion was not associated with haemolysis, but this method may result in insufficient flow rates for effective resuscitation. CONCLUSIONS: There is a paucity of high-quality evidence surrounding the risks of red cell haemolysis in IO blood transfusion. However, evidence from one study suggests that the likelihood is increased by use of a three-way tap to administer blood transfusion to young adult male patients with trauma. Further research is needed to address this important clinical question. PROSPERO REGISTRATION NUMBER: CRD42022318902.

Age, Sex, and BMI Differences Related to Repairable Meniscal Tears in Pediatric and Adolescent Patients.

BACKGROUND: The incidence of meniscus tears and ACL tears in pediatric patients continues to rise, bringing to question the risk factors associated with these injuries. As meniscus tears are commonly repaired in pediatric populations, the epidemiology of repairable meniscus tears is an important for consideration for surgeons evaluating treatment options. PURPOSE: To describe meniscal tear patterns in pediatric and adolescent patients who underwent meniscal repair across multiple institutions and surgeons, as well as to evaluate the relationship between age, sex, and body mass index (BMI) and their effect on the prevalence, type, and displacement of repaired pediatric meniscal tears. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Data within a prospective multicenter cohort registry for quality improvement, Sport Cohort Outcome Registry (SCORE), were reviewed to describe repaired meniscal tear patterns. All consecutive arthroscopic meniscal repairs from participating surgeons in patients aged <19 years were analyzed. Tear pattern, location, and displacement were evaluated by patient age, sex, and BMI. A subanalysis was also performed to investigate whether meniscal tear patterns differed between those occurring in isolation or those occurring with a concomitant anterior cruciate ligament (ACL) injury. Analysis of variance was used to generate a multivariate analysis of specified variables. Sex, age, and BMI results were compared across the cohort. RESULTS: There were 1185 total meniscal repairs evaluated in as many patients, which included 656 (55.4%) male and 529 (44.6%) female patients. Patients underwent surgery at a mean age of 15.3 years (range, 5-19 years), with a mean BMI of 24.9 (range, 12.3-46.42). Of the 1185 patients, 816 (68.9%) had ACL + meniscal repair and 369 (31.1%) had isolated meniscal repair. The male patients underwent more lateral tear repairs than the female patients (54.3% to 40.9%; P < .001) and had a lower incidence of medial tear repair (32.1% vs 41.4%; P < .001). Patients with repaired lateral tears had a mean age of 15.0 years, compared with a mean age of 15.4 years for patients with repaired medial or bilateral tears (P = .001). Higher BMI was associated with "complex" and "radial" tear repairs of the lateral meniscus (P < .001) but was variable with regard to medial tear repairs. CONCLUSION: In pediatric and adolescent populations, the data suggest that the surgical team treating knees with potential meniscal injury should be prepared to encounter more complex meniscal tears, commonly indicated in those with higher BMI, while higher rates of lateral meniscal tears were seen in male and younger patients. Future studies should analyze correlates for meniscal repair survival and outcomes in this pediatric cohort undergoing knee surgery.

Procedural sedation at role 1: applicability to military clinicians and minimum monitoring criteria.

Procedural sedation is defined as producing a state of reduced consciousness, where the patient is still able to respond to verbal or physical stimulus and to continuously maintain a patent airway and adequate ventilation. This can be done to facilitate treatment that would not be otherwise possible. Recent evidence, guidelines and new equipment introductions have improved the safety of procedural sedation at UK role 1 medical treatment facilities (MTFs). A role 1 MTF is defined by the North Atlantic Treaty Organization as a medical facility focusing on the provision of primary healthcare, specialised first aid, triage, resuscitation and stabilisation, and is usually staffed by a general practitioner or a general duties medical officer. This paper aims to update role 1 clinicians on the current evidence base and guidance regarding monitoring of patients during procedural sedation.

Reconciling the Potentially Irreconcilable? Genotypic and Phenotypic Amoxicillin-Clavulanate Resistance in Escherichia coli.

Resistance to amoxicillin-clavulanate, a widely used beta-lactam/beta-lactamase inhibitor combination antibiotic, is rising globally, and yet susceptibility testing remains challenging. To test whether whole-genome sequencing (WGS) could provide a more reliable assessment of susceptibility than traditional methods, we predicted resistance from WGS for 976 Escherichia coli bloodstream infection isolates from Oxfordshire, United Kingdom, comparing against phenotypes from the BD Phoenix (calibrated against EUCAST guidelines). A total of 339/976 (35%) isolates were amoxicillin-clavulanate resistant. Predictions based solely on beta-lactamase presence/absence performed poorly (sensitivity, 23% [78/339]) but improved when genetic features associated with penicillinase hyperproduction (e.g., promoter mutations and copy number estimates) were considered (sensitivity, 82% [277/339]; P < 0.0001). Most discrepancies occurred in isolates with MICs within ±1 doubling dilution of the breakpoint. We investigated two potential causes: the phenotypic reference and the binary resistant/susceptible classification. We performed reference standard, replicated phenotyping in a random stratified subsample of 261/976 (27%) isolates using agar dilution, following both EUCAST and CLSI guidelines, which use different clavulanate concentrations. As well as disagreeing with each other, neither agar dilution phenotype aligned perfectly with genetic features. A random-effects model investigating associations between genetic features and MICs showed that some genetic features had small, variable and additive effects, resulting in variable resistance classification. Using model fixed-effects to predict MICs for the non-agar dilution isolates, predicted MICs were in essential agreement (±1 doubling dilution) with observed (BD Phoenix) MICs for 691/715 (97%) isolates. This suggests amoxicillin-clavulanate resistance in E. coli is quantitative, rather than qualitative, explaining the poorly reproducible binary (resistant/susceptible) phenotypes and suboptimal concordance between different phenotypic methods and with WGS-based predictions.

Are battlefield and prehospital trauma scenarios an effective educational tool to teach leadership and crisis resource management skills to undergraduate medical students?

INTRODUCTION: Leadership and crisis resource management (CRM) skills are important skills for doctors, however there is a recognised lack of undergraduate leadership education. There remains debate over how best to teach leadership and CRM skills, and poor leadership skills among clinicians are associated with adverse patient outcomes. We examined whether high-fidelity battlefield and prehospital scenarios can improve leadership and CRM skills. METHOD: This was a prospective observational study with students self-reporting their leadership and CRM skills using the Ottawa Crisis Resource Management Global Ranking Scale (OCRMGRS) before and after completing the Cambridge University Emergency Medicine Society Battlefield and Pre-Hospital Trauma course. The course involves a mixture of small group tutorials and practical high-fidelity battlefield and prehospital trauma scenarios. Faculty also completed the OCRMGRS for the first and last candidates at the scenarios. The mean precourse versus mean postcourse score of the OCRMGRS was analysed using a two-tailed t-test. RESULTS: 46 students completed paired OCRMGRS before and after the course. The mean precourse scores for each of the domains (leadership, communication skills, resource utilisation, problem solving skills and situational awareness) were calculated. There was a statistically significant (p<0.05) increase in both self-reported and faculty-reported scores across all domains, and the increase remained at 1-year follow-up. CONCLUSIONS: Leadership and CRM skills are important non-clinical skills for doctors, however there is debate over how best to teach them. High-fidelity battlefield and prehospital trauma scenarios are an effective means of teaching leadership and CRM skills to civilian medical students.

Reducing Time to First on Scene: An Ambulance-Community First Responder Scheme.

The importance of early access to prehospital care has been demonstrated in many medical emergencies. This work aims to describe the potential time benefit of implementing a student Community First Responder scheme to support ambulance services in an inner-city setting in the United Kingdom. Twenty final and penultimate year medical students in the UK were trained in the "First Person on Scene" Business and Technology Education Council (BTEC) qualification. Over 12 months, they attended 89 emergency calls in an inner-city setting as Community First Responders (CFRs), alongside the West Midlands Ambulance Service, UK. At the end of this period, a qualitative survey investigated the perceived educational value of the scheme. The mean CFR response time across all calls was an average of 3 minutes and 8 seconds less than ambulance crew response times. The largest difference was to calls relating to falls (12 min). The difference varied throughout the day, peaking between 16:00 and 18:00. All questionnaire respondents stated that they felt more prepared in assessing and treating acutely unwell patients. In this paper, the authors present a symbiotic solution which has both reduced time to first on scene and provided training and experience in medical emergencies for senior medical students.

An unusual case of abdominal sepsis following traumatic injury.

A 19-year-old woman presented to our emergency department with crampy abdominal pain and per rectal bleeding 2 weeks after falling from a horse. She had been taking regular non-steroidal anti-inflammatory drugs (NSAIDs) for analgaesia. On arrival, she was tachycardic and tachypnoeic, with a lactate of 7.3 mmol/L. 'FAST' ultrasonography was unremarkable and CT scan showed thickened wall of the transverse colon. She underwent flexible sigmoidoscopy, which demonstrated "patchy inflammation and an isolated area of severe deep ulceration with nodularity and oedema". A presumptive diagnosis of "Inflammatory Bowel Disease-likely Crohn's", was made, and treated accordingly with steroids and Pentasa. Two months following discharge, the patient underwent a colonoscopy, showing a normal colon, however, "a few ulcers in the terminal ileum" were seen. She was seen by a gastroenterologist who deemed the most likely diagnosis to be NSAID-induced terminal ileitis and colitis. Having stopped the offending NSAID (and steroids), she has now made a full recovery.