Q:

4/29/2013
Are there any updated, formal or informal, policies regarding scuba diving in asthmatics? I cannot find any recent recommendations. Thanks.

A:

Thank you for your inquiry.

The last guidelines (actually a report of the scuba committee of the AAAAI) on scuba diving I am aware of were published in 1995. Butyou might find the reviews of this issue cited below helpful.

The most recent review article on scuba diving of which I am aware was published in 2007. In the last decade there have been several other informative reviews however, and I have copied abstracts of these for you below. As noted, to my knowledge, no information has been published in this regard since 2007, and I could not find any with a literature search. I hope, however, that these are of help to you.

Thank you again for your inquiry.

Harefuah. 2007 Apr;146(4):286-90, 317.
[Asthma and scuba diving: can asthmatic patients dive?].
[Article in Hebrew]
Sade K, Wiesel O, Kivity S, Levo Y.
Source
Department of Medicine 'T', Sourasky Medical Center, Tel Aviv University, Tel Aviv, Israel.
Abstract
Self-contained underwater breathing apparatus (scuba) diving has grown in popularity, with millions of divers enjoying the sport worldwide. This activity presents unique physical and physiological challenges to the respiratory system, raising numerous concerns about individuals with asthma who choose to dive. Asthma had traditionally been a contraindication to recreational diving, although this caveat has been ignored by large numbers of such patients. Herein we review the currently available literature to provide evidence-based evaluation of the risks associated with diving that are posed to asthmatics. Although there is some indication that asthmatics may be at an increased risk of pulmonary barotrauma, the risk seems to be small. Thus, under the right circumstances, patients with asthma can safely participate in recreational diving without any apparent increased risk of an asthma-related event. Decisions on whether or not diving is hazardous must be made on an individual basis and be founded upon an informed decision shared by both patient and physician

Clin Rev Allergy Immunol. 2005 Oct;29(2):131-8.
Asthma and the diver.
Davies MJ, Fisher LH, Chegini S, Craig TJ.
Source
Department of Asthma, Allergy, and Immunology, The Pennsylvania State University, Milton S. Hershey Medical Center, Hershey, PA, USA.
Abstract
Self-contained underwater breathing apparatus (scuba) diving has grown in popularity, with nearly 9 million sport divers in the United States alone. Approximately 7% of the population has been diagnosed with asthma, which is similar to the percentage of divers admitting they have asthma. Numerous concerns exist regarding subjects with asthma who choose to participate in recreational diving. Among these concerns are pulmonary barotrauma, pneumomediastinum, pneumothorax, arterial gas embolism, ear barotrauma, sinus barotrauma, and dental barotrauma. Despite these concerns, a paucity of information exists linking asthma to increased risk of diving complications. However, it has long been the norm to discourage individuals with asthma from participating in recreational scuba diving. This article examines the currently available literature to allow for a more informed decision regarding the possible risks associated with diving and asthma. It examines the underlying physiological principles associated with diving, including Henry's law and Boyle's law, to provide a more intimate understanding on physiological changes occurring in the respiratory system under compressive stress. Finally, this article offers a framework for guiding the patient with asthma who is interested in scuba diving. Under the right circumstances, the patient with asthma can safely participate in recreational diving without apparent increased risk of an asthma-related event.

Curr Sports Med Rep. 2005 Oct;4(5):275-81.
Controversies in the medical clearance of recreational scuba divers: updates on asthma, diabetes mellitus, coronary artery disease, and patent foramen ovale.
Harrison D, Lloyd-Smith R, Khazei A, Hunte G, Lepawsky M.
Source
Department of Family Practice, Student Health Service, University of British Columbia, M334-2211 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada.
Abstract
Primary care and sports medicine physicians are frequently consulted on medical clearance for prospective recreational divers. We discuss four common and controversial medical conditions--asthma, diabetes mellitus, coronary artery disease, and patent foramen ovale--as they relate to fitness to dive. For each condition we review the relevant anatomy and physiology, current recommendations, and the pertinent medical literature. Finally, we offer evidence-based recommendations regarding fitness to dive for potential divers with these conditions.

Sports Med. 2003;33(2):109-16.
Asthma and recreational SCUBA diving: a systematic review.
Koehle M, Lloyd-Smith R, McKenzie D, Taunton J.
Source
Allan McGavin Sports Medicine Centre, Department of Family Practice and the School of Human Kinetics, University of British Columbia, Vancouver, British Columbia, Canada.
Abstract
Asthma has traditionally been a contraindication to recreational self-contained underwater breathing apparatus (SCUBA) diving, although large numbers of patients with asthma partake in diving. The purpose of this paper is to review all the research relevant to the issue of the safety of asthma in divers. MEDLINE and MDConsult were searched for papers between 1980-2002. Keywords used for the search were 'asthma', 'SCUBA' and 'diving'. Additional references were reviewed from the bibliographies of received articles.A total of fifteen studies were identified as relevant to the area. These included three surveys of divers with asthma, four case series and eight mechanistic investigations of the effect of diving on pulmonary function. The survey data showed a high prevalence of asthma among recreational SCUBA divers, similar to the prevalence of asthma among the general population. There was some weak evidence for an increase in rates of decompression illness among divers with asthma. In healthy participants, wet hyperbaric chamber and open-water diving led to a decrease in forced vital capacity, forced expired volume over 1.0 second and mid-expiratory flow rates. In participants with asymptomatic respiratory atopy, diving caused a decrease in airway conductivity. There is some indication that asthmatics may be at increased risk of pulmonary barotrauma, but more research is necessary. Decisions regarding diving participation among asthmatics must be made on an individual basis involving the patient through informed, shared decision making.

Sincerely,
Phil Lieberman, M.D.

AAAAI - American Academy of Allergy Asthma & Immunology