Hyperbaric effects on cold stored whole blood following a military dive mission profile.

BACKGROUND: Whole blood (WB) is carried by special operations forces as part of a remote damage control resuscitation strategy. The effects of an underwater mission on the quality and coagulation profile of WB were simulated by exposure to hyperbaric pressures in a chamber. METHODS: WB units collected in CPDA-1 were exposed to three different combinations of hyperbaric pressure and duration of exposure: Group A 153.52 kPa (15.24 msw; 1.52 atm) for 4 h; n = 9, Group B 506.63 kPa (50.29 msw; 5.00 atm) for 1 h; n = 9, Group C 153.52 kPa (15.24 msw; 1.52 atm) for 1 h; n = 7. The following parameters were measured on each unit: prothrombin time/international normalized ratio, activated partial thromboplastin time, thromboelastography and concentration determinations of platelets, lactate, fibrinogen, and lactate dehydrogenase. Each sample underwent baseline, prepressurization, immediate postpressurization, and 6 h postpressurization laboratory testing. RESULTS: Six hours following hyperbaric exposure, the lactate concentration in group C was higher than prepressurization measurement and the platelet concentration in Group A was lower than prepressurization measurement. There were no changes in any of the other analyzed biochemical, coagulation and thromboelastogram parameters following exposure to hyperbaric stress. DISCUSSION: These data suggest that pressurization of WB up to 5 atm did not impact parameters tested. Changes observed in lactate and platelet count need further study, as well as complementary testing of red blood cell integrity. Further investigation of the hyperbaric extremes is necessary to determine if there is a damage inducing pressure to which WB should not be exposed.

The Perfect Med Bag is One that Doesn't Fall Off a Cliff: A Combat Mass Casualty Case.

Military trauma provides a unique pattern of injuries due to the high velocity, high kinetic energy ammunition utilized, and the high prevalence of blast injury. To further complicate this, military trauma often occurs in austere environments with limited logistical support. Therefore, military medical providers are forced to learn nonstandard techniques and when necessary, practice a level of improvisation not commonly seen in other medical fields. The case presented in this manuscript is a prime example of these challenges. At the onset of fighting both the medic's rucksack, carrying with it the primary source of medical gear and the precious supply of cold-stored blood products are lost. The scenario was further complicated by rough mountainous terrain and a prolonged evacuation time. The medical provider was forced to utilize nonstandard devices such as an improvised junctional tourniquet which used a rock to focus the devices pressure. They also adapted their basic understanding of surgical procedures to conduct a vascular cutdown procedure for wound exposure and effectively pack an otherwise non-compressible wound to a major artery. Despite a significant loss of equipment, the medic and their team were able to successfully care for a number of patients in this mass casualty scenario.

Should All Patients With Pulmonary Hypertension Undergoing Non-Cardiac Surgery Be Managed by Cardiothoracic Fellowship-Trained Anesthesiologists?

OBJECTIVES: To identify differences in practice patterns and outcomes related to the induction of general anesthesia for patients with pulmonary hypertension (PH) performed by anesthesiologists who have completed a cardiothoracic fellowship (CTA group) vs those who have not (non-CTA group). DESIGN: Retrospective study with propensity score matching. SETTING: Operating room. PARTICIPANTS: All adult patients with PH undergoing general anesthesia requiring intubation at a single academic center over 5 years. INTERVENTIONS: Patient baseline characteristics, peri-induction management variables, post-induction mean arterial pressure (MAP), and other outcomes were compared between CTA and non-CTA groups. METHODS AND MAIN RESULTS: Following propensity scoring matching, 402 patients were included in the final model, 100 in the CTA group and 302 in the non-CTA group. Also following matching, only cases of mild to moderate PH without right ventricular dysfunction remained in the analysis. Matched groups were overall statistically similar with respect to baseline characteristics; however, there was a greater incidence of higher ASA class (P = .025) and cardiology and thoracic procedures (P < .001) being managed by the CTA group. No statistical differences were identified in practice patterns or outcomes related to the induction of anesthesia between groups, except for longer hospital length of stay in the CTA group (P = .008). CONCLUSIONS: These results provide early evidence to suggest the induction of general anesthesia of patients with non-severe PH disease can be comparably managed by either anesthesiologists with or without a cardiothoracic fellowship. However, these findings should be confirmed in a prospective study.

Approach to Handling Atypical Field Blood Transfusion Scenarios.

Special Operations Forces (SOF) medical personnel have been at the forefront of administering blood products in the austere field medicine environment. These far-forward medical providers regularly treat patients and deliver blood transfusions in some of the world's most extreme environments with minimal resources. A multitude of questions have been raised on this topic based on the unique experiences of senior providers in this field. In this paper, we analyze the available literature and present the recommendations of several experts in transfusion medicine for managing atypical field transfusion scenarios.

Combating the Current Pandemic and Preparing for the Next: Lessons Learned From the COVID-19 Pandemic From the Perspective of Deployed Special Operations Forces.

The coronavirus 2019 (COVID-19) pandemic continues to be a threat to global health, including the health of deployed armed forces. Servicemembers had to adjust to the "new normal" while maintaining the interests of the nation's security as well as that of our host nation partners. This commentary examines how Special Operations Forces operating within four different regions worldwide leveraged the challenges presented by the onset of this pandemic in maintaining stability, sustaining a ready force, and operating forward deployed. Deployed forces face constant difficulties with logistical support, varied medical resources access and a medical system predominantly focused on trauma care. At the onset of the COVID-19 pandemic there was little guidance specific to these circumstances which required an improvised adaptation of the recommendations set by national and Department of Defense medical authorities. Plans were constantly revised to match the ever changing medical and operational environment. Strategies such as the "Bubble Philosophy" and tiered force protection measures helped our units to maintain a rigorous training cycle. New methods of communication and training with our host nation partners such as the use of Unmanned Aerial Systems (UAS) platforms to survey host nation training became standard. Through these measures all of our forces were able to maintain operational capacity, protect the force, and maintain rapport with the host nations. We hope these experiences will provide a rough framework for future forces faced with a similar struggle. We also want to stress that challenges vary depending on the area of operations and the pathogen responsible for the pandemic. Any feedback and collaboration that may come from this work is appreciated and encouraged.