Vital Signs After Cardiac Arrest Following Withdrawal of Life-Sustaining Therapy

Abstract

This is the first observational study to prospectively collect waveform data for 30 minutes after the declaration of death. A future larger study may support initial data suggesting that circulatory function does not resume after more than 89 seconds of absence. Furthermore, persistence of cardiac electrical activity with the documented absence of circulation may not be relevant to declaration of death.

Physiologic Changes in the Heart Following Cessation of Mechanical Ventilation in a Porcine Model of Donation After Circulatory Death: Implications for Cardiac Transplantation

“…First, all hearts exhibited organized ventricular electrical activity at the time circulatory arrest was declared; however, it was clear that no antegrade circulation was present and no oxygen delivery was occurring. In an observational study of human patients undergoing WLST, Dhanani et al (12) have also observed that electrocardiographic activity persists after declaration of circulatory arrest in the majority of patients. Our results support the opinion that the standoff period should commence when mechanical asystole (no pulse pressure on an arterial pressure tracing) has occurred, and that waiting for electrical asystole lacks a sound physiologic rationale.…”

“…Second, we did not observe any autoresuscitation events following declaration of circulatory arrest. Dhanani et al (12) observed a transient return of arterial blood pressure activity in 4 (13%) patients following declaration of circulatory arrest; however, the pulse pressure amplitude observed is unlikely to have actually been associated with cerebral perfusion (33). The observation of arterial blood pressure activity following declaration of circulatory arrest has generated extensive ethical debate regarding the minimum warm ischemic standoff period that must be observed before organ procurement can proceed.…”

“…), standoff period durations that must be observed before death can be declared (2-20 min), and definitions of the functional warm ischemic time that are employed in the donation community (2,(8)(9)(10)(11)). An improved understanding regarding the natural history of the dying process following donor extubation is necessary to inform the development of standardized medical practices for DCD (12).…”

Pediatric Donation After Circulatory Determination of Death

“…Consequences of death determination in pDCDD require a high degree of certainty in the time of death (21,23,27,28,41,73). Recommended tests should be sensitive, objective, and standardized (18,51,53,73,75,76).…”

“…Many concerns around pDCDD, such as the physiology of the dying process after WLST, may be addressed with further research (41,55), including studies currently underway (http//:www.ddepict.com). However, the lack of knowledge in pDCDD is not limited to questions researchers can easily answer through clinical trials or even qualitative studies.…”