Abstract
The Relationship of Decongestant Use and Risk of Decompression Sickness: A Case-Control Study of Hawaiian Scuba Divers
Vasoconstriction underlies the pathophysiology of several well-established and suggested risk factors for decompression sickness (DCS) in divers, such as exposure to cold, dehydration, aging, hypertension, and nicotine use. Vasoconstriction is associated with a greater degree of bubble formation during dive decompression and alters gas kinetics within the vasculature, potentially leading to a slower rate of off-gassing. Divers commonly use sympathomimetic decongestants for prophylaxis of barotrauma to the ears and sinuses before diving; however, these agents also cause vasoconstriction. This records-based, case-control study investigated the risk of using sympathomimetic decongestants and subsequent development of DCS.
In all, 400 cases were selected from among recreational divers evaluated or treated for DCS at the University of Hawai’i John A. Burns School of Medicine between 1983 and 2010. Patients treated for DCS were compared with “controls” who did not exhibit signs or symptoms of DCS after diving. Decongestants, the independent variable, were defined as medications containing pseudoephedrine, phenylephrine, oxymetazoline, or xylometazoline and were used topically or orally. The investigators found a small, but statistically insignificant, positive risk for the development of DCS in divers using oral or topical decongestants within 12 hours of the incident dive (OR 1.4, 95% confidence interval: 0.8 to 2.6, P = .22).
Other known DCS risk factors were also analyzed in this study. Dehydration, repetitive diving, and violation of dive profiles had a statistically significant positive effect on the development of DCS. Limitations of the study include the potential for information bias due to poor historical documentation, not specifying decongestant dosage, and small sample size. The authors conclude that sympathomimetic decongestants did not increase the risk of DCS developing, whereas dehydration, repetitive diving, and dive profile violation contributed significantly to DCS.
(Hawai’i J Med Pub Health. 2014;73:61–64). RW Smertz.