RESUMEN
OBJECTIVE: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a method of gaining proximal control of noncompressible torso hemorrhage (NCTH). Catheter placement is traditionally confirmed with fluoroscopy, but few studies have evaluated whether ultrasound (US) can be used. METHODS: Using a pressurized human cadaver model, a certified REBOA placer was shown one of four randomized cards that instructed them to place the REBOA either correctly or incorrectly in Zone 1 (the distal thoracic aorta extending from the celiac artery to the left subclavian artery) or Zone 3 (in the distal abdominal aorta, from the aortic bifurcation to the lowest renal artery). Once the REBOA was placed, 10 US-trained locators were asked to confirm balloon placement via US. The participants were given 3 minutes to determine whether the catheter had been correctly placed, repeating this 20 times on two cadavers. RESULTS: Overall, US exhibited an average sensitivity of 83%, specificity of 76%, and accuracy of 80%. For Zone 1, US showed a sensitivity of 78% and specificity of 83%, and for Zone 3, a sensitivity of 88% and specificity of 76%. In addition, US exhibited a likelihood positive ratio (LR+) of 3.73 and a likelihood negative ratio (LR-) of 0.22 for either position, with similar numbers for Zone 1 (+4.57, -0.26) and Zone 3 (+3.16, -0.16). CONCLUSION: Ultrasound could prove to be a useful tool for confirming placement of a REBOA catheter, especially in austere environments.
Asunto(s)
Oclusión con Balón , Procedimientos Endovasculares , Choque Hemorrágico , Humanos , Procedimientos Endovasculares/métodos , Torso , Aorta Abdominal/diagnóstico por imagen , Resucitación/métodos , Oclusión con Balón/métodos , Cadáver , Choque Hemorrágico/diagnóstico por imagen , Choque Hemorrágico/terapiaRESUMEN
Trauma casualty care has historically been the cornerstone of special operations military medical training. A recent case of myocardial infarction at a remote base of operations in Africa highlights the importance of foundational medical knowledge and training. A 54-year-old government contractor supporting operations in the AFRICOM area of responsibility (AOR) presented to the Role 1 medic with substernal chest pain with onset during exercise. Abnormal rhythm strips concerning for ischemia were obtained from his monitors. A MEDEVAC to a Role 2 facility was arranged and executed. At the Role 2 a non-ST-elevation myocardial infarction (NSTEMI) was diagnosed. The patient was emergently evacuated on a lengthy flight to a civilian Role 4 treatment facility for definitive care. He was found to have a 99% occlusion of the left anterior descending (LAD) coronary artery, as well as a 75% occlusion of the posterior coronary artery and a chronic 100% occlusion of the circumflex artery. The LAD and posterior arteries were stented, and the patient made a favorable recovery. This case highlights the importance of preparedness for medical emergencies and care of medically critical patients in remote and austere locations.
Asunto(s)
Infarto del Miocardio , Infarto del Miocardio sin Elevación del ST , Masculino , Humanos , Persona de Mediana Edad , Infarto del Miocardio sin Elevación del ST/cirugía , Electrocardiografía , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/terapia , Vasos Coronarios , África Occidental , Angiografía CoronariaRESUMEN
OBJECTIVE: Intraosseous (IO) access is critical in resuscitation, providing rapid access when peripheral vascular attempts fail. Unfortunately, misplacement commonly occurs, leading to possible fluid extravasation and tissue necrosis. Current research exploring the utility of bedside ultrasound in confirming IO line placement is limited by small sample sizes of skeletally immature subjects or geriatric cadaveric models. The objective of this study was to investigate the potential value of ultrasound confirming IO needle placement in a live tissue model with bone densities approximated to the young adult medical or trauma patient. MATERIALS AND METHODS: In this randomized, blinded prospective study, IO devices were placed into the bilateral humeri of 36 sedated adult swine (N = 72) with bone densities approximating that of a 20-39-year-old adult. Of the 72 lines, 53 were randomized to the IO space ("correct") and 19 into the subcutaneous tissue ("incorrect"). Four emergency physicians with variable ultrasound experience and blinded to needle location independently assessed correct or incorrect needle placements based on the presence of an intramedullary "flare" on color power Doppler (CPD) during a saline flush. Participants adjusted the ultrasound beam trajectory and recorded assessments up to three times, totaling 204 separate observations. RESULTS: Overall, sensitivity for placement confirmation was 72% (95% CI: 64%-79%). Specificity was 79% (95% CI: 66%-89%). First assessment and final assessment results were similar. More experienced sonographers demonstrated greater success in identifying inaccurate placements with a specificity of 86% (95% CI: 63%-96%). CONCLUSION: Within the context of this study, point-of-care ultrasound with CPD did not reliably confirm IO line placement. However, more accurate assessments of functional and malpositioned catheters were noted in sonographers with greater than 4 years of experience. Future study into experienced sonographers' use of CPD to confirm IO catheter placement is needed.
Asunto(s)
Agujas , Sistemas de Atención de Punto , Animales , Infusiones Intraóseas , Estudios Prospectivos , Resucitación/métodos , Sus scrofa , PorcinosRESUMEN
OBJECTIVES: Intraosseous (IO) access can provide a critical bridge for blood product infusion when peripheral venous access is not obtainable. Successful pressurized IO infusion requires flow rates sufficient to preserve life, but with infusion pressures low enough to avoid clinical complications (e.g., hemolysis, bone damage, fat emboli). However, the optimal method for pressured IO delivery of blood was unknown. METHODS: Three trained physicians infused 500 mL of whole blood through a 15-gauge, 45 mm IO catheter into fresh, high bone density cadaveric swine proximal humeri. Participants applied eight different pressure infusion strategies: (1) gravity, (2) pressure bag, (3) pressure bag actively maintained at or above 300 mmHg, (4) hand pump, (5) hand pump with pressure bag, (6) push-pull with 10 mL syringe, (7) push-pull with 60 mL syringe, and a (8) Manual Rapid Infuser in a randomized within-subjects design (30 trials per method, 240 trials total). The primary outcomes of flow rates, mean and peak pressures, and user ratings were contrasted using ANOVA at p < 0.05. RESULTS: The Manual Rapid Infuser conferred the highest flow rates (199 ± 3 mL/min) and most favorable user ratings, but also the highest mean and peak pressures. Push-pull conferred the next highest flow rates (67 ± 5 mL/min for 60 mL, 56 ± 2 mL/min for 10 mL) and pressures, with intermediate-to-high user ratings. Hand pump flow rates were essentially identical with (45 ± 4 mL/min) or without (44 ± 3 mL/min) pressure bag, with high user ratings without a pressure bag. Pressure bag and gravity methods conferred low flow rates and user ratings. CONCLUSIONS: Some pressured IO infusion methods can achieve flow rates adequate to serve as a resuscitative bridge in the massively hemorrhaged trauma victim, but flow rates and pressures vary greatly across IO pressurized infusion methods. Manual Rapid Infuser and push-pull methods conferred high flow rates but also relatively high pressures, highlighting the importance of using in vivo models in future research to assess the possible clinical complications of using these promising methods. Combined, present findings highlight the importance of studying pressurized IO methods towards preserving the life of the critically injured trauma victim.