Circum-rescue Collapse is a complex physical phenomenon that can occur immediately before, during or shortly after rescue from cold water. Its symptoms can range from fainting to death due to cardiac arrest.
In simple terms, the causes center around the body’s lack of ability to maintain proper heart function, blood pressure, and core temperature under the stressful conditions of cold water immersion and/or the demanding physical requirements of the rescue itself. This condition was well documented in World War II when it was found that the safe recovery of downed pilots and sailors was greatly enhanced when rescued horizontally instead of pulled vertically from the water (thereby relieving some of the strain on the heart).
However, in some cases, even shortly after rescue, the consequence of rapid body cooling may cause the heart to continue to cool, until it reaches the temperature threshold for spontaneous cardiac arrest. In addition, stress hormones may also play a role. In this case, these hormones increase muscle strength and help maintain blood pressure during cooling. However, the rescue process could decrease the levels of these hormones due to mental relaxation, and that could cause a decrease in blood pressure. To complicate matters, if a victim is placed in a vertical position, it causes the blood to pool in the legs and decreases blood pressure even more. The combination of a cooling heart and increased cardiac work to maintain blood pressure may cause symptoms ranging from fainting to cardiac arrest.1
Today, understanding Circum-rescue Collapse, and using some simple, practical rescue techniques, can help prevent this tragedy. The materials you’ll find throughout Beyond Cold Water Boot Camp are designed to help you do just that.
1 Gordon G. Giesbrecht, PhD; John S. Hayward, PhD (2006). Problems and Complications with Cold-Water Rescue. Wilderness and Environmental Medicine, 17, 26 30