Laypeople perception and interpretation of simulated life-threatening bleeding: a controlled experimental study

Abstract

Introduction First aid performed by immediate responders can be the difference between life and death in the case of trauma with massive bleeding. To develop effective training programs to teach bleeding control to laypersons, it is important to be aware of beliefs and misconceptions people hold on bleeding and severity of bleeding situations. Method A controlled study was conducted in which 175 American college students viewed 78 video clips of simulated bleeding injuries. The volume of blood present (between 0 and 1900 ml), rate of blood flow, and victim gender were systematically varied within participants. Participants were asked to rate injury severity, indicate the appropriate first aid action, and estimate the amount of time until death for the victim. Results Though the Stop the Bleed® campaign recommends training laypeople to treat 165 ml of blood loss as life threatening, participants largely rated this volume of blood loss as minimal, mild, or moderate and estimated that the victim had just under one hour to live. Increased blood loss was associated with increased recommendations to use a tourniquet. However, in the 1900 ml conditions, participants still estimated that victims had around 22 minutes to live and approximately 15% recommended direct pressure as the intervention. Severity ratings and recommendations to use a tourniquet were also higher for the male victim than the female victim. Conclusions Injury classification, intervention selection, and time to death-estimations revealed that training interventions should connect classifications of blood loss to appropriate action and focus on perceptions of how much time one has to respond to a bleeding. The study also revealed a gender related bias in terms of injury classification and first aid recommendations. Bleeding control training programs can be designed to address identified biases and misconceptions while building on existing knowledge and commonly used terminology.

Dynamics of Local Temperature in the Fingertips After the Cuff Occlusion Test: Infrared Diagnosis of Adaptation Reserves to Hypoxia and Assessment of Survivability of Victims at Massive Blood Loss

“…Currently, methods such as laser Doppler flowmetry and photoplethysmography are used to assess blood volume and blood flow [ 8 , 9 , 10 ]. The modern classification of blood loss is based on the relationship of calculated blood loss values to such clinical indicators as pulse rate, blood pressure, respiratory rate, diuresis rate and mental state [ 11 ]. At the same time, the use of this classification to assess the severity of blood loss in clinical practice has known limitations and drawbacks [ 12 ].…”