Termination of resuscitation measures

Time criteria and rescuer factors

The decision to stop cardiopulmonary resuscitation (CPR) is based on clear time and situational criteria. If the ongoing interventions yield absolutely no results (the patient has persistent total cyanosis and persistent asystole is registered on the monitor), basic life support may be terminated after 15–20 minutes.

The absolute temporal indicator of ineffectiveness is recognized as the absence of any signs of spontaneous breathing and circulation recovery for 30 minutes from the start of chest compressions and artificial ventilation. At the same time, if the victim shows at least a short-term positive response, resuscitation is not time-limited — it is continued as long as clinical efficacy persists.

A special group consists of factors directly related to the person providing assistance. CPR is immediately terminated if there is an objective threat to the rescuer's life and safety. A legitimate reason to stop chest compressions is also the extreme degree of physical exhaustion of the rescuer, when they are physically incapable of maintaining an adequate rhythm and depth of compressions.

Early post-mortem changes

The appearance of reliable early post-mortem changes serves as an absolute basis for terminating resuscitation attempts and declaring biological death. These include specific eye reactions, as well as physical changes in tissues.

• Ocular signs: Corneal clouding occurs rapidly, known as the "melting ice sign". Upon lateral compression of the eyeball, the pupil assumes an elongated oval shape — this is the Beloglazov phenomenon, or "cat's eye sign".
• Post-mortem cooling (Algor mortis): Body temperature gradually drops to the ambient level. This happens due to the complete cessation of heat production with ongoing physical heat dissipation, which is visually accompanied by severe pallor of the skin.
• Post-mortem drying: Areas lacking a full protective epidermis lose moisture first. The cornea, lips, and fingertips become thin and dry.
• Livor mortis (Livores mortis): Blood flows under the influence of gravity to the dependent parts of the body. The process has three stages: hypostasis (spots move and lighten upon pressure), stasis (diffusion begins, spots pale more slowly), and imbibition (persistent soaking of surrounding tissues with blood, spots no longer disappear).
• Rigor mortis (Rigor mortis): Post-mortem stiffening of skeletal and smooth muscles. The mechanism is directly related to the biochemical breakdown of ATP and the accumulation of lactic acid in muscle fibers. The process starts a few hours later, spreads from top to bottom, and resolves on its own when muscle tissue autolysis begins.

Late post-mortem changes

If the body remains in specific conditions for a long time, late changes develop. In the context of emergency medicine, these are encountered when a body is discovered a significant time after death.

1. Putrefaction: Tissue decomposition under the influence of putrefactive microflora. The process is accompanied by the release of gases (ammonia, hydrogen sulfide, methane), leading to post-mortem emphysema (pronounced abdominal distension), the appearance of characteristic corpse greenness, and massive epidermal detachment.
2. Mummification: Natural dehydration of body tissues. It occurs in dry air and with good ventilation. Tissues are preserved, and bacterial putrefaction is practically non-existent.
3. Adipocere (saponification): Develops under conditions of high humidity and oxygen deficiency. Body fats undergo saponification, turning into a specific dense mass that preserves the body.

Antemortem processes mimicking post-mortem ones

In surgical and infectious disease practice, it is important to distinguish classic post-mortem phenomena from pathological processes that developed while the patient was still alive.

For example, in dry gangrene of a limb, a process occurs that is clinically identical to mummification, but local. Dead tissues dry out rapidly without infection, the skin turns black, and a clear demarcation line forms, separating the dead area from the healthy one (intoxication is minimal).

Another striking example is the algid stage in cholera. The patient's body may look like a corpse due to severe exicosis (dehydration). Due to antemortem clonic seizures, a specific "gladiator posture" is formed, in which the limbs and fingers are rigidly bent. Muscles become dense and dark red, the spleen shrinks, and dry serous membranes are covered with petechial hemorrhages and a sticky coating ("soap-soaped" effect). Blood in the vessels becomes thick and dark. In such situations, antemortem pathomorphological changes outwardly closely resemble early post-mortem ones, creating a specific morphological picture.

Class and exam questions

What else to study on this topic

• Pathogenesis of livor mortis formation by stages
• Biochemical mechanisms of rigor mortis and muscle autolysis
• Conditions for the development of late post-mortem phenomena (adipocere, putrefaction, mummification)
• Clinical picture of the algid stage of cholera
• Differences between pathological mummification in dry gangrene and post-mortem changes

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.