Repetitive freshwater diving: risk factors and prevalence of barotrauma.

OBJECTIVE: The aim was to investigate the influence of repetitive scuba diving in fresh water on the middle ear mucosa. The prevalence of middle ear barotrauma (MEB) and risk factors for MEB were evaluated. STUDY DESIGN: Prospective cohort study, Level of evidence 1b. METHODS: During three days, 23 divers made 144 repetitive dives in a freshwater lake. Participants underwent otoscopic examinations and were questioned about ENT-related complaints in the morning before the first dive, in between the dives and after the last dive. Otoscopic findings were documented and classified according to the TEED scale (0 = normal eardrum to 4 = perforation), for the right and the left ear separately. RESULTS: In total, 416 examinations were performed. ENT-related complaints during diving, mostly failed pressure equalization (74%), were reported after 10% of all dives. Most common pathology was MEB (TEED 1-3, 26%). Valsalva maneuver was possible during all exams. Significant increase of MEB (TEED⟩0) occurred with an increasing cumulative number of dives per day (P ⟨ .0001). Diving depth significantly influenced the MEB distribution (P = .035). MEB with higher TEED levels (2 and 3) was present only in the less experienced and intermediate divers. With increasing TEED level, more participants reported ENT-related problems (P ⟨ .0001). However, 74.4% of divers with MEB were still asymptomatic. CONCLUSION: During three days of diving, the MEB prevalence increased with a cumulative number of dives per day. The major risk factors were diving depth and diving experience. Higher TEED level correlated with an increasing number of subjective ENT-related disorders during diving.

Influence of repetitive diving in freshwater on pressure equalization and Eustachian tube function in recreational scuba divers.

INTRODUCTION: We investigated the effect of repetitive pressure exposure during freshwater dives on Eustachian tube function and the middle ear, assessed by the Eustachian tube function test (ETFT). METHODS: This prospective observational cohort study included 23 divers over three consecutive days of diving in freshwater lakes in Nordhausen, Germany. Participants underwent otoscopy and ETFT before the first dive, between each dive and after the last dive. ETFT included regular tympanometry (R-tymp), tympanometry after Valsalva (V-tymp) and after swallowing (S-tymp). The peak pressure difference between the R-tymp and the V-tymp (R-VdP) defined effectiveness of pressure equalization after Valsalva manoeuvres. We evaluated the change in compliance and peak pressure and correlated the results to the otoscopic findings and diving experience. RESULTS: Twenty-three divers performed 144 dives. Middle ear barotrauma was assessed using the Edmonds modification of the TEED scoring system. In the ETFT, the R-tymp peak pressure displayed a negative shift from day one to three (P = 0.001) and differed significantly between the experience groups (P = 0.01). R-VdP did not change significantly on any of the three days of diving (all P > 0.05). Participants without MEBt showed significantly lower R-tymp values than did those with barotrauma (P = 0.019). CONCLUSION: Repetitive pressure exposure during three consecutive days of freshwater diving led to a negative shift of the peak pressure in the middle ear. Less experienced divers showed significantly higher middle ear peak pressure and higher pressure differences after equalization manoeuvres. Higher middle ear peak pressure was also associated with a higher prevalence of barotrauma.

Influence of repetitive diving in saltwater on pressure equalization and Eustachian tube function in recreational scuba divers.

INTRODUCTION: We investigated in a prospective, observational trial the feasibility of using the Eustachian tube function test (ETFT) to measure the effect of repetitive pressure exposure during open seawater dives on Eustachian tube function. METHODS: The study included 28 adult divers during six consecutive days of diving in the Red Sea. Participants underwent otoscopy and ETFT before the first dive, between each dive and after the last dive. ETFT included regular tympanometry (R-tymp), tympanometry after Valsalva (V-tymp) and after swallowing (S-tymp). The R-tymp was obtained as 'baseline' peak pressure. After a Valsalva, the peak pressure should shift (positively), revealing a positive shift of the tympanic membrane. This pressure shift is defined here as R-VdP. The changes in compliance and peak pressure were recorded and correlated with otoscopic findings and diving experience. Middle ear barotrauma was scored using the Edmonds modified TEED scale. RESULTS: The 28 participants performed 437 dives. Positive shift of pressure in the middle ear was evident with significant changes from day one to day three (P < 0.0001). Divers with barotrauma showed significantly lower values of R-tymp peak pressure and significantly higher negative R-VdP, compared to divers with normal otoscopic findings (P < 0.05). Diving experience significantly correlated with R-tymp peak pressure and prevalence of middle ear barotrauma. CONCLUSION: Significant changes in middle ear pressure and pressure equalization from repeated pressure exposure in saltwater were seen using ETFT. Repetitive, multi-day diving led to significantly decreased compliance and increased R-tymp peak pressure (overpressure) in the middle ear. Most profound changes were observed in less and intermediate experienced divers.

Prevalence of Barotrauma in Recreational Scuba Divers After Repetitive Saltwater Dives.

INTRODUCTION: The aim was to investigate the prevalence of middle ear barotrauma (MEB) and to establish risk factors of MEB after repeated saltwater dives. METHODS: In this prospective observational cohort study 28 divers were examined over 6 consecutive days of diving in the Red Sea, Egypt. Participants underwent an otoscopic examination before the first dive, between each dive and after the last dive. In addition, they performed Valsalva maneuver (VM) and were questioned about dive-related complaints. Otoscopic findings were classified according to TEED classification for MEB (0 = normal otoscopy to 4 = perforation) separately for each ear. First examination was conducted before the first dive. Final examination, including a questionnaire, was conducted at least 12 h after the last dive. RESULTS: In total, 436 dives were performed and 1161 otoscopic findings were analyzed. All participants showed a normal eardrum and a positive VM during initial exam. MEB prevalence (TEED >0) was 36.5% at final examination. Prevalence increased significantly with number of dives per day (p < 0.001) as with number of diving days (p = 0.032). Neither depth nor duration of dives significantly influenced MEB prevalence (all p > 0.05). More experienced divers (>200 dives lifetime) showed significantly less barotrauma (p < 0.0001). Despite the high prevalence of MEB, 81.7% (316 of 387) of all dives were reported asymptomatic. CONCLUSIONS: After 6 days of repetitive diving, MEB prevalence was high (36.5%). It was the most often cause of otalgia in divers. Cumulative pressure exposure during repetitive dives resulted in significant increase of MEB. Diving experience significantly reduced the MEB prevalence. Interestingly, the severity of MEB did not correlate with subjective complaints.