The effectiveness of the manual pressure points technique for hemorrhage control-The 2022 THOR pre-conference meeting experience.

INTRODUCTION: Limb and junctional hemorrhage are leading causes of potentially preventable death among trauma casualties. Hemorrhage control for these regions could be achieved by direct or indirect pressure. The manual pressure points (MPP) involves applying manual pressure on the arterial supply to occlude distal blood flow without the need for specialized equipment. STUDY DESIGN AND METHODS: Prospective, non-randomized, human volunteer, controlled environment study involving 38 healthy military caregivers, with 26 participants attending a short instructional session. During a medical exercise, participants were requested to apply pressure on the supraclavicular and femoral points aiming to stop regional blood flow, measured by distal pulse palpation. The measures recorded included achievement of distal pulse cessation, success in achieving cessation for a full minute, and subjects' pain scores reported after each attempt. RESULTS: All participants succeeded in achieving distal pulse cessation for both the supraclavicular and femoral points for a full minute. The median time to initial success was 3.0 (interquartile range 2.0-5.0) seconds in the supraclavicular point and 4.5 (interquartile range 3.0-6.0) seconds in the femoral point. Pain scores ranging between 0 and 3 were reported by most subjects during supraclavicular (68.4%) and femoral occlusion (84.2%). CONCLUSION: The MPP technique was highly effective in occluding distal palpable pulses in healthy volunteers when applied to the supraclavicular and femoral arteries. Brief instruction on the technique can potentially improve the chances of achieving hemorrhage control within 5 s. Further research is required to determine efficacy among different populations and providers with varying experience levels.

A Pilot Trial of Platelets Stored Cold versus at Room Temperature for Complex Cardiothoracic Surgery.

BACKGROUND: This pilot trial focused on feasibility and safety to provide preliminary data to evaluate the hemostatic potential of cold-stored platelets (2° to 6°C) compared with standard room temperature-stored platelets (20° to 24°C) in adult patients undergoing complex cardiothoracic surgery. This study aimed to assess feasibility and to provide information for future pivotal trials. METHODS: A single center two-stage exploratory pilot study was performed on adult patients undergoing elective or semiurgent complex cardiothoracic surgery. In stage I, a two-armed randomized trial, platelets stored up to 7 days in the cold were compared with those stored at room temperature. In the subsequent single-arm stage II, cold storage time was extended to 8 to 14 days. The primary outcome was clinical effect measured by chest drain output. Secondary outcomes were platelet function measured by multiple electrode impedance aggregometry, total blood usage, immediate and long-term (28 days) adverse events, length of stay in intensive care, and mortality. RESULTS: In stage I, the median chest drain output was 720 ml (quartiles 485 to 1,170, n = 25) in patients transfused with room temperature-stored platelets and 645 ml (quartiles 460 to 800, n = 25) in patients transfused with cold-stored platelets. No significant difference was observed. The difference in medians between the room temperature- and cold-stored up to 7 days arm was 75 ml (95% CI, -220, 425). In stage II, the median chest drain output was 690 ml (500 to 1,880, n = 15). The difference in medians between the room temperature arm and the nonconcurrent cold-stored 8 to 14 days arm was 30 ml (95% CI, -1,040, 355). Platelet aggregation in vitro increased after transfusion in both the room temperature- and cold-stored platelet study arms. Total blood usage, number of adverse events, length of stay in intensive care, and mortality were comparable among patients receiving cold-stored and room temperature-stored platelets. CONCLUSIONS: This pilot trial supports the feasibility of platelets stored cold for up to 14 days and provides critical guidance for future pivotal trials in high-risk cardiothoracic bleeding patients.

"Blood failure" time to view blood as an organ: how oxygen debt contributes to blood failure and its implications for remote damage control resuscitation.

Hemorrhagic shock is both a local and systemic disorder. In the context of systemic effects, blood loss may lead to levels of reduced oxygen delivery (DO2 ) sufficient to cause tissue ischemia. Similar to other physiologic debts such as sleep, it is not possible to incur a significant oxygen debt and suffer no consequences for lack of timely repayment. While the linkage between oxygen debt and traditional organ failure (renal, hepatic, lung, and circulation) has been long recognized, we should consider failure in two additional linked and very dynamic organ systems, the endothelium and blood. These systems are very sensitive to oxygen debt and at risk for failing, having further implications on all other organ systems. The degree of damage to the endothelium is largely modulated by the degree of oxygen debt. Thus hypoperfusion is believed to begin a cascade of events leading to acute traumatic coagulopathy (ATC). This combination of oxygen debt driven endothelial damage and ATC might be considered collectively as "blood failure" due to the highly connected networks between these drivers. This article presents the implications of oxygen debt for remote damage control resuscitation strategies, such as permissive hypotension and hemostatic resuscitation. We review the impact of whole blood resuscitation and red blood cell efficacy in mitigation of oxygen debt. At last, this article recognizes the need for simple and durable, lightweight equipment that can detect the adequacy of tissue DO2 and thus patient needs for resuscitative care. Point-of-care lactate measuring may be a predictive tool for identifying high-risk trauma patients and occult shock because it provides information beyond that of vital signs and mechanism of injury as it may help predict the level of oxygen debt accumulation and need for resuscitation. Serial measurements may also be valuable as a tool in guiding resuscitative efforts.

The lost art of whole blood transfusion in austere environments.

The optimal resuscitation fluid for uncontrolled bleeding and hemorrhagic shock in both pre- and in-hospital settings has been an ongoing controversy for decades. Hemorrhage continues to be a major cause of death in both the civilian and military trauma population, and survival depends on adequacy of hemorrhage control and resuscitation between onset of bleeding and arrival at a medical treatment facility. The terms far-forward and austere are defined, respectively, as the environment where professional health care providers normally do not operate and a setting in which basic equipment and capabilities necessary for resuscitation are often not available. The relative austerity of a treatment setting may be a function of timing rather than just location, as life-saving interventions must be performed quickly before hemorrhagic shock becomes irreversible. Fresh whole blood transfusions in the field may be a feasible life-saving procedure when facing significant hemorrhage.

Airway and ventilation management strategies for hemorrhagic shock. To tube, or not to tube, that is the question!

Many standard trauma management guidelines advocate the early use of endotracheal intubation (ETI) and positive pressure ventilation as key treatment interventions in hemorrhagic shock. The evidence for using these airway and ventilation strategies to manage a circulation problem is unclear. The potentially harmful effects of drug-assisted intubation and positive pressure ventilation include reduced cardiac output, apnea, hypoxia, hypocapnea (due to inadvertent hyperventilation), and unnecessarily prolonged on-scene times. Conversely, the beneficial effects of spontaneous negative pressure ventilation on cardiac output are well described. Few studies, however, have attempted to explore the potential advantages of a strategy of delayed intubation and ventilation (together with a policy of aggressive volume replacement) in shocked trauma patients. Given the lack of evidence, the decision making around how, when, and where to subject shocked trauma patients to intubation and positive pressure ventilation remains complex. If providers choose to delay intubation, they must have the appropriate skills to safely manage the airway and recognize the need for subsequent intervention. If they decide to perform intubation and positive pressure ventilation, they must understand the potential risks and how best to minimize them. We suggest that for patients with hemorrhagic shock who do not have a compromised airway and who are able to maintain adequate oxygen saturation (or mentation if monitoring is unreliable), a strategy of delayed intubation should be strongly encouraged. LEVEL OF EVIDENCE: Review article, level IV.

Immediate effects of blood donation on physical and cognitive performance-A randomized controlled double-blinded trial.

BACKGROUND: The success of implementing damage control resuscitation principles pre-hospital has been at the expense of several logistic burdens including the requirements for resupply, and the question of donor safety during the development of whole blood programs. Previous studies have reported effects on physical performance after blood donation; however, none have investigated the effects of blood donation on cognitive performance. METHOD: We describe a prospective double-blinded, randomized, controlled study comprised of a battery of tests: three cognitive tests, and VO2max testing on a cycle ergometer. Testing was performed 7 days before blinded donation (baseline day), immediately after donation (Day 0), and 7 days (Day 7) after donation. The inclusion criteria included being active blood donors at the Haukeland University Hospital blood bank, where eligibility requirements were met on the testing days, and providing informed consent. Participants were randomized to either the experimental (n = 26) or control group (n = 31). Control group participants underwent a 'mock donation" in which a phlebotomy needle was placed but blood was not withdrawn. RESULTS: In the experimental group, mean ± SEM VO2max declined 6% from 41.35 ± 1.7 mLO2/(min·kg) at baseline to 39.0 ± 1.6 mLO2/(min·kg) on Day 0 and increased to 40.51 ± 1.5 mLO2/(min·kg) on Day 7. Comparable values in the control group were 42.1 ± 1.8 mLO2/(min·kg) at baseline, 41.6 ± 1.8 mLO2/(min·kg)) on Day 1 (1% decline from baseline), and 41.8 ± 1.8 mLO2/(min·kg) on Day 7.Comparing scores of all three cognitive tests on Day 0 and Day 7 showed no significant differences (p > 0.05). CONCLUSION: Our main findings are that executive cognitive and physical performances were well maintained after whole blood donation in healthy blood donors. The findings inform postdonation guidance on when donors may be required to return to duty. LEVEL OF EVIDENCE: Randomized, controlled, double-blinded prospective trial study, level 1.

Blood far forward: Time to get moving!

In planning for future contingencies, current problems often crowd out historical perspective and planners often turn to technological solutions to bridge gaps between desired outcomes and the reality of recent experience. The US Military, North Atlantic Treaty Organization, and other allies are collectively taking stock of 10-plus years of medical discovery and rediscovery of combat casualty care after the wars in Iraq and Afghanistan. There has been undeniable progress in the treatment of combat wounded during the course of the conflicts in Southwest Asia, but continued efforts are required to improve hemorrhage control and provide effective prehospital resuscitation that treats both coagulopathy and shock. This article presents an appraisal of the recent evolution in medical practice in historical context and suggests how further gains in far forward resuscitation might be achieved using existing technology and methods based on whole-blood transfusion while research on new approaches continues.