Occup Environ Med 2002 Sep;59(9):629-33 Related Articles, Links
Lung function over six years among professional divers.
Skogstad M, Thorsen E, Haldorsen T, Kjuus H.
National Institute of Occupational Health, PO Box 8149 Dep., N-0033 Oslo, Norway.
marit.skogstad@stami.no
AIMS: To analyse longitudinal changes in pulmonary function in professional divers and their relation with cumulative diving exposure. METHODS: The study included 87 men at the start of their education as professional divers. At follow up one, three, and six years later, 83, 81, and 77 divers were reexamined. The median number of compressed air dives in the 77 divers over the follow up period was 196 (range 37-2000). A group of non-smoking policemen (n = 64) were subjected to follow up examinations in parallel with the divers. Assessment of lung function included dynamic lung volumes, maximal expiratory flow rates, and transfer factor for carbon monoxide (Tl(CO)). The individual rates of change of the lung function variables were calculated by fitting linear regression lines to the data, expressed as percent change per year. RESULTS: The annual reductions in forced vital capacity (FVC) and forced expired volume in one second (FEV(1)) were 0.91 (SD 1.22) and 0.84 (SD 1.28) per cent per year in divers, which were significantly higher than the reductions in the policemen of 0.24 (SD 1.04) and 0.16 (SD 1.07) per cent per year (p < 0.001). The annual reduction in the maximal expiratory flow rates at 25% and 75% of FVC expired (FEF(25%) and FEF(75%)) were related to the log(10) transformed cumulative number of dives in a multiple regression analysis (p < 0.05). The annual reductions in Tl(CO) were 1.33 (SD 1.85) and 0.43 (SD 1.53) per cent per year in divers and policemen (p < 0.05). CONCLUSIONS: FVC, FEV(1), maximal expiratory flow rates, and Tl(CO) were significantly reduced in divers over the follow up period when compared with policemen. The contrasts within and between groups suggest that diving has contributed to the reduction in lung function.
PMID: 12205238 [PubMed - indexed for MEDLINE]
OR
Scand J Work Environ Health 1999 Feb;25(1):67-74 Related Articles, Links
Functional and high-resolution computed tomographic studies of divers' lungs.
Reuter M, Tetzlaff K, Steffens JC, Gluer CC, Faeseke KP, Bettinghausen E, Heller M.
Department of Diagnostic Radiology, Christian-Albrechts-University, Kiel, Germany.
OBJECTIVES: Several cross-sectional studies have described a decrease in the expiratory flow rates of divers. The objective of this study was to determine whether the combined application of high-resolution computed tomography (HRCT) and lung function testing supports the reported development of small airway obstruction in divers. METHODS: Thirty-two navy divers, 27 commercial divers, and 48 referents matched for age and smoking history underwent pulmonary function testing and HRCT of the lungs supplemented by a limited number of expiratory scans. The commercial divers were older and dived longer than the navy divers. Multivariate regression analysis was used to assess the relevant correlations of age, height, pack-years of cigarette smoking, and indices of diving exposure with lung function parameters. RESULTS: The inspiratory vital capacity and forced vital capacity (FVC) were greater, while the FEV% [(100 x FEV10)FVC] and maximum expiratory flow (MEF) at 25% (MEF25) of the FVC were lower for the navy divers than for the referents. The lung volumes and expiratory airflow pattern did not differ between the commercial divers and the corresponding referents. The forced expiratory volume in 1 second (FEV10), FEV%, MEF75, and MEF25 correlated negatively with the years of diving experience. This association was independent of age, height, and pack-years of cigarette smoking. For the majority of the divers and referents the expiratory HRCT revealed minor lobular air trapping without any difference between the groups. The HRCT did not show relevant morphologic abnormalities of small or large airways. CONCLUSIONS: The data confirm that diving may affect pulmonary function. However, there is no radiologic evidence for the development of small airway disease in these 2 subgroups of divers.
PMID: 10204673 [PubMed - indexed for MEDLINE]
OR
Clin Sci (Lond) 1994 Mar;86(3):297-303 Related Articles, Links
Role of cardiorespiratory abnormalities, smoking and dive characteristics in the manifestations of neurological decompression illness.
Wilmshurst P, Davidson C, O'Connell G, Byrne C.
Department of Cardiology, St Thomas' Hospital, London, U.K.
1. Blind analysis of contrast echocardiograms to detect intracardiac shunts, blind analysis of lung function tests for evidence of small airways disease, smoking history and dive characteristics were examined in an attempt to explain neurological symptoms that occurred within 5 min of surfacing from unprovocative dives. 2. Pulmonary abnormalities were significantly more frequent in those divers without intracardiac shunts (50%) than in those with shunts (0%). Smoking was more common in those divers without shunts (55% versus 15%), although this just failed to reach conventional significance levels. Divers without shunts experienced cerebral rather than spinal symptoms after significantly shallower dives with lower tissue nitrogen loads. Depths of dives, tissue nitrogen loads and clinical manifestations in those divers without shunts were similar to the findings in divers who had symptoms after rapid ascents. Despite conservative dive profiles, clinical manifestations in divers with shunts resembled those observed after missed decompression stops. 3. The findings suggest that occult lung disease, and probably smoking, increase the risk of neurological symptoms, even after unprovocative dives, and the similarity of the dive profiles and clinical manifestations to cases with rapid ascents suggest that pulmonary barotrauma and arterial gas embolism are responsible. In divers with intracardiac shunts the different dive profiles and clinical manifestations imply that there is another mechanism, involving different tissue and bubble nitrogen kinetics resulting in venous gas liberation and peripheral amplification in embolized tissues, rather than paradoxical embolism per se.
PMID: 8156740 [PubMed - indexed for MEDLINE]
