Abstract

BACKGROUND Despite significant attempts to educate civilians in hemorrhage control, the majority remain untrained. We sought to determine if laypersons can successfully apply one of three commercially available tourniquets; including those endorsed by the United States Military and the American College of Surgeons. METHODS Pre-clinical graduate health science students were randomly assigned a commercially-available windless tourniquet: SAM(R) XT, Combat Application Tourniquet(R) (CAT), or Special Operation Forces(R) Tactical Tourniquet (SOFT-T). Each was given up to one minute to read package instructions and asked to apply it to the HapMed(R) Leg Tourniquet Trainer. Estimated blood loss was measured until successful hemostatic pressure was achieved or simulated death occurred from exsanguination. Simulation survival, time to read instructions and stop bleeding, tourniquet pressure, and blood loss were analyzed. RESULTS Of the 150 students recruited, 55, 46, and 49 were randomized to the SAM XT, CAT, SOFT-T, respectively. Mean overall simulation survival was less than 66% (61%, 72%, 65%; p=0.55). Of survivors, all three tourniquets performed similarly in median pressure applied (319 mmHg, 315 mmHg, and 329 mmHg; p=0.54) and median time to stop bleeding (91 sec, 70 sec, 77 sec; p=0.28). There was a statistical difference in median blood loss volume favoring SOFT-T (SAM XT 686 ml, CAT 624 ml, SOFT-T 433 ml; p=0.03). All 16 participants with previous experience were able to successfully place the tourniquet compared to 81 of 131 (62%) first-time users (p=0.008). CONCLUSION No one should die of extremity hemorrhage, and civilians are our first line of defense. We demonstrate that when an untrained layperson is handed a commonly accepted tourniquet, failure is unacceptably high. Current devices are not intuitive and require training beyond the enclosed instructions. Plans to further evaluate this cohort after formal "Stop the Bleed" training are underway. LEVEL OF EVIDENCE Level II; Therapeutic study type.

Abstract

BACKGROUND Platelet transfusions are used to prevent and treat bleeding in patients who are thrombocytopenic. Despite improvements in donor screening and laboratory testing, a small risk of viral, bacterial or protozoal contamination of platelets remains. There is also an ongoing risk from newly emerging blood transfusion-transmitted infections (TTIs) for which laboratory tests may not be available at the time of initial outbreak.One solution to reduce further the risk of TTIs from platelet transfusion is photochemical pathogen reduction, a process by which pathogens are either inactivated or significantly depleted in number, thereby reducing the chance of transmission. This process might offer additional benefits, including platelet shelf-life extension, and negate the requirement for gamma-irradiation of platelets. Although current pathogen-reduction technologies have been proven significantly to reduce pathogen load in platelet concentrates, a number of published clinical studies have raised concerns about the effectiveness of pathogen-reduced platelets for post-transfusion platelet recovery and the prevention of bleeding when compared with standard platelets. OBJECTIVES To assess the effectiveness of pathogen-reduced platelets for the prevention of bleeding in patients requiring platelet transfusions. SEARCH METHODS We searched the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library2013, Issue 1), MEDLINE (1950 to 18 February 2013), EMBASE (1980 to 18 February 2013), CINAHL (1982 to 18 February 2013) and the Transfusion Evidence Library (1980 to 18 February 2013). We also searched several international and ongoing trial databases and citation-tracked relevant reference lists. We requested information on possible unpublished trials from known investigators in the field. SELECTION CRITERIA We included randomised controlled trials (RCTs) comparing the transfusion of pathogen-reduced platelets with standard platelets. We did not identify any RCTs which compared the transfusion of one type of pathogen-reduced platelets with another. DATA COLLECTION AND ANALYSIS One author screened all references, excluding duplicates and those clearly irrelevant. Two authors then screened the remaining references, confirmed eligibility, extracted data and analysed trial quality independently. We requested and obtained a significant amount of missing data from trial authors. We performed meta-analyses where appropriate using the fixed-effect model for risk ratios (RR) or mean differences (MD), with 95% confidence intervals (95% CI), and used the I2 statistic to explore heterogeneity, employing the random-effects model when I2 was greater than 30%. MAIN RESULTS We included 10 trials comparing pathogen-reduced platelets with standard platelets. Nine trials assessed Intercept pathogen-reduced platelets and one trial Mirasol pathogen-reduced platelets. Two were randomised cross-over trials and the remaining eight were parallel-group RCTs. In total, 1422 participants were available for analysis across the 10 trials, of which 675 participants received Intercept and 56 Mirasol platelet transfusions. Four trials assessed the response to a single study platelet transfusion (all Intercept) and six to multiple study transfusions (Intercept (N = 5), Mirasol (N = 1)) compared with standard platelets.We found the trials to be generally at low risk of bias but heterogeneous regarding the nature of the interventions (platelet preparation), protocols for platelet transfusion, definitions of outcomes, methods of outcome assessment and duration of follow-up.Our primary outcomes were mortality, 'any bleeding', 'clinically significant bleeding' and 'severe bleeding', and were grouped by duration of follow-up: short (up to 48 hours), medium (48 hours to seven days) or long (more than seven days). Meta-analysis of data from five trials of multiple platelet transfusions reporting 'any bleeding' over a long follow-up period found an increase in bleeding in those receiving pathogen-reduced platelets compared with standard platele