Dysautonomia Complicated by DDAVP Use for Diabetes Insipidus

Abstract

This is the case of a normal, healthy 42-year old woman who sustained injuries in a spinning motor vehicle accident, leaving her with a series of diagnoses including Dysautonomia, that stumped all doctors. Because she was a Stanfordtrained anesthesiologist and intensivist, she was able to self-diagnose several major illnesses, including traumatic brain injury (TBI), diabetes insipidus (DI), vertebral artery dissection (VAD) with aneurysm, oculo-vestibular dysfunction, and hypothyroidism. The DI required prescription DDAVP therapy to prevent dehydration and death. Here, we focus on the entities of the “see-saw” effect that DDAVP has on Total Body Water (TBW), hyponatremia, hypernatremia, and the complications arising from the chronic, underlying hypovolemic state of dysautonomia. Dysautonomia, an “Invisible Illness” causing dysfunction of the autonomic nervous system, is a frequently undiagnosed, hypovolemic state that can lead to syncope. The best-case scenario is to titrate the DDAVP clinically with a tendency to under rather than to over-dose, preventing hypervolemia and hyponatremia. One can also provide ambient temperature and avoid overheating, consider insensible water loss, allow the pituitary gland healing, prevent further falls or head injuries, and recognize when it is time to go off the DDAVP. There are a paucity of scientific data on DI, and its incidence is rare with coincidental dysautonomia. These entities need to be appreciated and diagnosed, especially when they occur simultaneously. The patient is in a precarious position of dying from either too much TBW (i.e., hyponatremia, brain swelling, orbital swelling) or from too little TBW (i.e., decreased glomerular filtration rate, need for dialysis, death, and the need for fluid resuscitation that can also lead to death). Let us learn in a step-by-step fashion.