Cardiac return assist blanket (CRAB) safely increases central venous pressure

Area of Science:

• Emergency Medicine
• Cardiovascular Physiology
• Medical Device Innovation

Background:

• Severe hypotension, particularly during anaphylaxis, necessitates interventions to increase central venous pressure (CVP).
• The cardiac return assist blanket (CRAB) is a novel device designed to augment CVP.
• Understanding the quantitative relationship between CRAB pressure and CVP is crucial for its clinical application.

Purpose of the Study:

• To determine the relationship between applied CRAB pressure and the resulting change in central venous pressure (CVP).
• To compare the efficacy of the CRAB in increasing CVP against established methods like straight leg raise (SLR), Trendelenburg position, and intravenous fluid administration.
• To establish the pressure-response curve of the CRAB for CVP augmentation.

Main Methods:

• An interventional study involving 16 healthy volunteers.
• Application of CRAB pressure at incremental levels (10, 20, 30, 40 cmH2O).
• Comparative measurements of CVP changes induced by SLR, Trendelenburg position, and 1L of compound sodium lactate (CSL) infusion.

Main Results:

• The initial 10 cmH2O of CRAB pressure increased CVP by 3.7 mmHg.
• Each subsequent 10 cmH2O increment in CRAB pressure yielded an additional 0.9 mmHg increase in CVP.
• The CRAB at 40 cmH2O resulted in a total CVP increase of 6.41 mmHg, significantly exceeding increases from SLR (0.97 mmHg), Trendelenburg (0.75 mmHg), and CSL (0.69 mmHg).

Conclusions:

• The cardiac return assist blanket (CRAB) provides a controllable method for increasing central venous pressure (CVP).
• The CRAB demonstrates superior efficacy in elevating CVP compared to passive maneuvers (SLR, Trendelenburg) and fluid resuscitation (CSL).
• The findings support the potential of the CRAB as an effective tool for managing severe hypotension, particularly in anaphylaxis.