PUTTING IT ALL TOGETHER:  CRESS AND (MARCHE)²

Step 1: Hot Zone / Care Under Fire

The hot zone is an area where there is an immediate and ongoing threat to casualties and responders. During “hot zone” care, the agent itself is similar to enemy fire. As such, the priorities are protection and egress away from the threat (CBRN agent) for both casualty and provider. Both the casualty and provider should don protective masks. If the casualty is incapacitated, the provider must ensure the casualty’s protective gear is applied and functional.

Only rapid interventions for immediate life-threats should be addressed. This typically includes management of catastrophic hemorrhage, airway problems, and antidote administration before evacuating out of the hot zone for decontamination and further treatment. Massive hemorrhage, if present, is the most immediate life threat and control of hemorrhage supersedes other interventions. Massive hemorrhage, if compressible, should be treated according to TCCC guidelines with limb or junctional tourniquets, as applicable.

Perform a rapid assessment of the airway and respirations. Excessive secretions and increased respirations may indicate nerve agent exposure. Completion of the CRESS assessment will help determine if the symptoms are due to trauma or chemical agent exposure. Most airway and respiratory interventions should be deferred, though there are some interventions that may take priority over mask application. The decision to unmask a casualty to provide these interventions needs to be weighed against the risk of the contaminated environment.

Some CBRN agents are rapid killers. The CRESS assessment will quickly determine whether immediate antidotes are required. If exposure to a rapidly killing agent (i.e. nerve agent, cyanide, opioid incapacitating agent) is suspected, administer the appropriate antidotes (ATNAA/AAS, hydroxocobalamin, naloxone). Cyanide treatment can be considered in the hot zone, but the need to establish IV/IO access to administer hydroxocobalamin makes this a judgment call weighed against the time needed to reach the warm zone and the ongoing threat in the hot zone location. If nerve agent exposure is suspected (decreased level of consciousness, increased respirations, constricted pupils, increased secretions, diaphoretic skin), then the provider should direct self-administration of Antidote Treatment Nerve Agent Auto-injector (ATNAA) and Convulsant Antidote for Nerve Agent (CANA) or administer the antidotes for an incapacitated casualty. 

Rapid spot decontamination of skin or wounds is indicated when there is gross contamination on the skin or wounds or when protective gear is breached. If wound contamination with a chemical agent is suspected, immediately expose the wound to perform rapid spot decontamination even in a contaminated environment. This step is necessary even in a contaminated environment and may be lifesaving.

As in TCCC, non-essential interventions should be deferred until the next phase of care.