Exsanguinating cardiac arrest not always fatal

The British Military has developed a reputation for aggressive pre-hospital critical care including (but not limited to) the use of blood products and tourniquets, and coordinated field hospital trauma care. They now report the outcomes for patients with traumatic cardiac arrest, mainly from improvised explosive devices. Of 52 patients, 14 (27%) demonstrated return of spontaneous circulation (ROSC), of whom four (8%) survived to hospital discharge with a neurologically good recovery. Resuscitative thoracotomy (RT) was performed on 12 patients (8 in the ED), including all four survivors. RT enabled open-chest CPR, release of pericardial tamponade, lung resection and compression of the descending thoracic aorta for haemorrhage control.
No patients who arrested in the field survived, although one of the neurologically well-recovered survivors arrested during transport to hospital and was in cardiac arrest for 24 minutes. The authors propose this individual’s survival was in part due to ‘the high level of care that he received during retrieval, including haemorrhage control, tracheal intubation and transfusion of blood products‘.
Asystole was universally associated with death but agonal / bradycardic rhythms were not. In keeping with other studies, cardiac activity on ultrasound was associated with ROSC.

AIM: To determine the characteristics of military traumatic cardiorespiratory arrest (TCRA), and to identify factors associated with successful resuscitation.

METHODS: Data was collected prospectively for adult casualties suffering TCRA presenting to a military field hospital in Helmand Province, Afghanistan between 29 November 2009 and 13 June 2010.

RESULTS: Data was available for 52 patients meeting the inclusion criteria. The mean age (range) was 25 (18-36) years. The principal mechanism of injury was improvised explosive device (IED) explosion, the lower limbs were the most common sites of injury and exsanguination was the most common cause of arrest. Fourteen (27%) patients exhibited ROSC and four (8%) survived to discharge. All survivors achieved a good neurological recovery by Glasgow Outcome Scale. Three survivors had arrested due to exsanguination and one had arrested due to pericardial tamponade. All survivors had arrested after commencing transport to hospital and the longest duration of arrest associated with survival was 24min. All survivors demonstrated PEA rhythms on ECG during arrest. When performed, 6/24 patients had ultrasound evidence of cardiac activity during arrest; all six with cardiac activity subsequently exhibited ROSC and two survived to hospital discharge.

CONCLUSION: Overall rates of survival from military TCRA were similar to published civilian data, despite military TCRA victims presenting with high Injury Severity Scores and exsanguination due to blast and fragmentation injuries. Factors associated with successful resuscitation included arrest beginning after transport to hospital, the presence of electrical activity on ECG, and the presence of cardiac movement on ultrasound examination.

Outcomes following military traumatic cardiorespiratory arrest: A prospective observational study
Resuscitation. 2011 Sep;82(9):1194-7