Treatment of cardiac arrest in the hyperbaric environment: key steps on the sequence of care--case reports

The U.S. territory of Guam attracts thousands of military and civilian divers annually and is home to the only recompression facility within a 5,000-km radius that accepts critically injured dive casualties. As recompression chambers are confined spaces and standard use of electrical cardioversion cannot be used, cardiac resuscitation at depth must deviate from advanced cardiovascular life support (ACLS) algorithms. Furthermore, many hyperbaric chambers that accept dive casualties are in remote locations, a situation that requires providers to approach cardiac resuscitation in a different way when compared to an in-hospital or ICU setting. This presents a challenge to trained medical and diving professionals. We present two contrasting vignettes of diving injuries initially responsive to appropriate treatment but then deteriorating during recompression therapy and ultimately requiring resuscitation at depth. Additionally, we explore the physiologic basis of resuscitation in a hyperbaric environment as it relates to the treatment of cardiac arrest at depth. This review critically examines the current guidelines in place for emergency cardiac resuscitation in a hyperbaric chamber followed by recommendations for the key steps in the sequence of care.