Evolution of the ventilatory function of professional divers over 10 years.

INTRODUCTION

The study was aimed at assessing changes in respiratory function after 10 years of professional diving.

MATERIAL AND METHODS

A retrospective study was performed on divers who underwent an initial visit and a visit 10 years later at the same medical center. Pulmonary function tests were performed in the same laboratory with the same operating standards and using a Jaeger MasterBody plethysmograph. Each subject acted as his own control. The data were analyzed by Student's t-test and Spearman's correlation coefficient.

RESULTS

Thirty-three divers were included. Changes over 10 years included: decreases in the forced expiratory flow rates at 75% (-0.65 liters/second) (p < 0.01) and at 50% (-0.51 L/s) (p < 0.01) of forced vital capacity; significant decrease of the FEV1/FVC ratio (-3.4) (< 0.01); significant increases in total lung capacity (+0.32 L) (p = 0.03). The lung transfer factor for carbon monoxide (TL(CO)) had decreased significantly (-1.16 mmol/minute/kPa) (p = 0.02). The amount of smoking was significantly correlated with changes in slow vital capacity (R = 0.89; (p < 0.01). Changes in the FEV1/ FVC ratio were correlated with the mean duration of the dives (R = -0.59; (p < 0.01) and with the number of dives during the 10 years (R = -0.42; p = 0.04).

CONCLUSION

With increasing length of diving activities service, the pulmonary function displays a trend toward both a decrease in TL(CO) and a bronchial obstruction, extending to bronchi of increasing size.