Female professional divers. Similarities and differences between male and female professional divers.

BACKGROUND: The aim of the present study was to explore the potential differences between female and male professional divers with regards to demographics, diving certificates, areas of diving, diving activity and health effects. MATERIALS AND METHODS: The Norwegian Labour Inspection Authority's Diving certificate register contains data on all professional inshore divers who have held a certificate at any time since 1980. Forty nine per cent of these divers responded to the "Norwegian diver 2011" questionnaire. RESULTS: Of these divers 64 female and 1327 male divers completed the questionnaire about their professional diving career, certificate, year of onset and the year they stopped diving professionally if they were not still active in the diving industry. The level of general education was higher among female divers. More males than females were fully certified in diving. The mean age was lower among female than male fully certified divers. Fully certified female divers reported a lower total number of dives, shallower dives and diving for a shorter period of time than the male divers. They also had a lower percentage of work within the quay/construction sector and more often worked as teachers/instructors. A lower percentage of fully certified females than males had experienced decompression sickness (16.7% vs. 26.9%). Life-threatening events and psychologically challenging events were less common among females, as were adverse health effects. No such gender differences were seen for divers with a restricted certificate. CONCLUSIONS: The fully certified, female professional divers in our study had a very short diving career, reported fewer and shallower dives, and chose less physically demanding jobs than their male counterparts. They also had a higher level of education, reported less health problems and a better quality of life. The health effects seem to be related to the type of work rather than to gender.

Diving exposure and health effects in divers working in different areas of professional diving.

BACKGROUND: The aim of the present study was to compare diving exposure and health effects in different areas of professional diving. MATERIALS AND METHODS: The Norwegian Labour Inspection Authority's Diving Register contains data on all professional inshore divers who have held a diving certificate at any time since 1980. Of these divers, the "Norwegian diver 2011" questionnaire was completed by 2848 (48.7%). A total of 1167 male divers reported that they often worked in one area of diving only (rescue diving, diving instruction, fish farming, quay/construction work and offshore/oil related). In the analysis of these divers, rescue divers were used as referents as they reported the lowest number of dives. RESULTS: Age distribution, the proportion of retired divers and the mean number of dives completed varied between the different areas of professional diving. Compared to rescue divers, divers in fish farming, quay/ /construction work and offshore/oil related work more often experienced physically demanding diving. Divers in fish farming more often had no day off after 3 days of physically demanding work compared to rescue divers. All groups except offshore divers reported making further dives after one physically demanding dive on the same day. All groups reported more frequent decompression sickness than did the referents and divers in quay/construction and offshore/oil related diving reported more frequent episodes of unconsciousness during diving than did the referents. Divers in fish farming, in quay/construction work and oil/ /offshore related diving obtained a higher symptom score than the referents and the two latter groups also reported more frequent adverse health effects due to diving than the referents. Health related physical and mental component summary scores were lower in all other groups than in referents. CONCLUSIONS: Compared to the rescue divers, divers in quay/construction work and offshore/oil related divers reported more adverse health effects and obtained a higher symptom score.

A Confirmatory Factor Analytic Study of the Wechsler Memory Scale-III in an Elderly Norwegian Sample.

This study compared the factor structure of the translated Wechsler Memory Scale-III (WMS-III), which is the latest available version in Norway, with the original U.S. version. A sample of 122 healthy, elderly Norwegians (mean age: 74; standard deviation = 8.8) completed the WMS-III. The factor structure of the translated WMS-III was tested, using Confirmatory Factor Analysis, with comparison of model fit based on five a priori hypothesized models. Several model fit indices pointed to a three-factor model (working memory, visual memory, and auditory memory) providing the best fit to the data. Our study supports updated findings of the original WMS-III in nonclinical samples and suggests that the translated version is structurally equal to the original. The study supports the cross-cultural validity of the WMS-III. However, based on the present data, one might expect scores on the Family Pictures subtest to fall below scores on other WMS-III subtests in elderly Norwegians.

Prevalence and causes of loss of consciousness in former North Sea occupational divers.

BACKGROUND: Loss of consciousness (LOC) is a serious event during diving. The purpose of this study wasto estimate the prevalence and causes of LOC during diving in former North Sea divers, and the impacton health-related quality of life. MATERIALS AND METHODS: Up to 1990 a total of 373 Norwegian offshore divers worked in the North Sea. From 2000 to 2011, 221 of these were referred to the Department of Occupational Medicine at Haukeland University Hospital for examination due to health complaints. They filled in a questionnaire for registration of diving experience and health complaints, including the SF-36 version 1 for the assessment of quality oflife. The questionnaire and the hospital records were systematically reviewed by 2 independent observers. Episodes of LOC during diving and the causes were registered. All participants underwent a clinical neurological examination. Electroencephalogram (EEG) and the event-related brain potential (P300) were recorded. RESULTS: One or more episodes of LOC were reported by 58 of 219 divers. LOC due to gas cut was reportedby 27 of these. Divers having experienced LOC due to gas cut had lower SF-36 sub-scores then the rest of the diving population. EEG and P300 recordings did not differ between the groups. CONCLUSIONS: A high proportion of former Norwegian North Sea divers reported episodes of LOC, for whichgas cut was the most common cause. Both hypoxia and peritraumatic stress associated with the episodecould have a long term impact on the quality of life. Neurophysiological functions, however, did not differbetween the groups.

Risk of misclassification of decompression sickness.

Decompression sickness (DCS) is classified on the basis of which organ system is affected, and neurological DCS is considered more severe than DCS in joints and skin with respect to response to recompression treatment and risk of long-term sequelae. Gas bubble formation interstitially in the tissues or in the circulation is considered to be the mechanism for all types of DCS. Ten patients diagnosed as having DCS in joints or skin, by doctors experienced in diving medicine, underwent clinical examination by a neurologist and had an electroencephalogram. Eight of the ten subjects had findings suggesting central nervous system deficits. The findings indicate that DCS of the central nervous system often accompanies DCS of the joints and skin, and that local skin and joint symptoms may draw attention away from cerebral symptoms. We recommend that all cases with DCS should initially be treated as neurological DCS.

Pneumocephalus, a rare complication of diving.

BACKGROUND: Pneumocephalus is a recognized complication from head and facial traumas, sinus surgery and as a complication from otitis media acuta. Only a few cases of pneumocephalus related to diving have been reported. HISTORY: We report an occupational diver who suffered spontaneous subarachnoidal pneumocephalus related to a dive to 20 meters. At a depth of 17 msw he suffered from sudden onset of headache, dizziness, nausea and feeling of disorientation. He had no recognized risk factors such as documented facial fractures, rapid ascent or blocked sinuses. CT showed air in the subarachnoidal space. Otoneurological tests revealed pathological smooth pursuit tracking eye movements and substantial imbalance indicating a central neurological injury. CT and MRI showed a bony defect in the sphenoid sinus covered only by arachnoidea. This was probably the communicative fistula for the entrance of air. On follow-up examination one year later he still had central nervous symptoms and signs, as well as symptoms of post-traumatic stress disorder (PTSD.) He was not able to do any work and was declared unfit for further diving. We chose not to treat him with hyperbaric oxygen (HBO2) in the acute state because we thought HBO2 might have increased the amount of intracranial air. CONCLUSION: Pneumocephalus is a rare, but serious complication of diving. The condition should be suspected in a diver with increasing headache or other central nervous disturbancies during ascent. The treatment of pneumocephalus in divers is a matter of debate.

Cerebral diffusion and perfusion deficits in North Sea divers.

BACKGROUND: Diving is associated with a risk of cerebral decompression illness, and the prevalence of neurological symptoms is higher in divers compared with control groups. Microvascular dysfunction due to gas microembolism and exposure to hyperoxia are possible mechanisms, which may result in cerebral diffusion and perfusion deficits. PURPOSE: To investigate if possible functional derangements of the microvasculature and microstructure would be more prevalent among symptomatic divers. MATERIAL AND METHODS: Magnetic resonance imaging (MRI) was performed in 91 former divers and 45 controls. Individual parametric images of apparent diffusion coefficient (ADC), cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) were generated on the basis of diffusion- and perfusion-weighted imaging. To identify regions with statistically significant differences between groups (P < 0.05, corrected for false discovery rate), voxel-wise ANCOVA analysis was performed for each of the four parametric images. RESULTS: Significant regional group differences were found in all four parametric comparisons. Gross regional ADC differences were seen throughout the brain, including large frontal and temporal white-matter regions, the hippocampus, and parts of the cerebellum. Differences in the perfusion maps were localized in fewer and smaller clusters, including parts of the cerebellum, the putamen, and the anterior watershed regions. CONCLUSION: Regional functional abnormalities as measured by diffusion- and perfusion-weighted imaging were identified in the divers, and there was a partial co-localization of the regions identified in the perfusion and the diffusion images. The findings may explain some of the long-term clinical symptoms reported among professional divers.

Reduced health-related quality of life in former North Sea divers is associated with decompression sickness.

BACKGROUND: Diving is associated with long-term effects on several organ systems. AIM: The objective was to investigate the impact of decompression sickness (DCS) and diving exposure on health-related quality of life (HRQL) in former Norwegian North Sea divers. METHODS: HRQL was recorded by a questionnaire in the cohort of 375 Norwegian North Sea divers registered before 1990. Demographic data, relevant health data and data on diving education, history of DCS and SF-36 were recorded in 230 divers. RESULTS: All SF-36 sub-scores were significantly reduced compared with Norwegian norms. Reduced scores were seen for all scales among divers who reported previous DCS compared to those without DCS. A decreasing trend in scores was seen when comparing no DCS, skin or joint DCS and neurological DCS. There was a decreasing trend in scores related to number of days in saturation and maximal depth. Stratification on DCS showed that the impact of saturation diving was present only in divers with DCS. CONCLUSIONS: HRQL was reduced in this study sample of divers. Having had DCS during the diving career contributed significantly to the reduction in all SF-36 scales, and apparently neurological DCS has the most pronounced impact. Cumulative diving exposure including days in saturation and maximal depth contributed to a reduced HRQL.