Dive Hazards: Barotrauma, Flora, Fauna, Equipment, and Free Diving.

ABSTRACT: Present-day diving comes in various forms, from utilizing sophisticated diving equipment to relying solely on one's ability to hold their breath. The diver and physician must be aware of the many common medical conditions and environmental considerations of this unique activity. While barotrauma remains the most common dive-related injury, injuries and accidents also are related to diving equipment-related accidents and exposure to marine flora and fauna. In addition, breath-hold diving, which includes free diving, snorkeling, and tasks, is an activity humans have done for thousands of years for recreation or survival. This article will update the dangers of diving and methods to prevent or treat injuries.

Breath-Hold Diving Injuries - A Primer for Medical Providers.

ABSTRACT: Breath-hold divers, also known as freedivers, are at risk of specific injuries that are unique from those of surface swimmers and compressed air divers. Using peer-reviewed scientific research and expert opinion, we created a guide for medical providers managing breath-hold diving injuries in the field. Hypoxia induced by prolonged apnea and increased oxygen uptake can result in an impaired mental state that can manifest as involuntary movements or full loss of consciousness. Negative pressure barotrauma secondary to airspace collapse can lead to edema and/or hemorrhage. Positive pressure barotrauma secondary to overexpansion of airspaces can result in gas embolism or air entry into tissues and organs. Inert gas loading into tissues from prolonged deep dives or repetitive shallow dives with short surface intervals can lead to decompression sickness. Inert gas narcosis at depth is commonly described as an altered state similar to that experienced by compressed air divers. Asymptomatic cardiac arrhythmias are common during apnea, normally reversing shortly after normal ventilation resumes. The methods of glossopharyngeal breathing (insufflation and exsufflation) can add to the risk of pulmonary overinflation barotrauma or loss of consciousness from decreased cardiac preload. This guide also includes information for medical providers who are tasked with providing medical support at an organized breath-hold diving event with a list of suggested equipment to facilitate diagnosis and treatment outside of the hospital setting.

Pulmonary Physiology and Medicine of Diving.

Pulmonary physiology is significantly altered during underwater exposure, as immersion of the body and increased ambient pressure elicit profound effects on both the cardiovascular and respiratory systems. Thoracic blood pooling, increased breathing gas pressures, and variations in gas volumes alongside ambient pressure changes put the heart and lungs under stress. Normal physiologic function and fitness of the cardiovascular and respiratory systems are prerequisites to safely cope with the challenges of the underwater environment when freediving, or diving with underwater breathing apparatus. Few physicians are trained to understand the physiology and medicine of diving and how to recognize or manage diving injuries. This article provides an overview of the physiologic challenges to the respiratory system during diving, with or without breathing apparatus, and outlines possible health risks and hazards unique to the underwater environment. The underlying pathologic mechanisms of dive-related injuries are reviewed, with an emphasis on pulmonary physiology and pathophysiology.

Incidence of dental barotrauma and temporomandibular joint problems of divers in Turkey.

Introduction: In this study, we aimed to examine dental barotrauma and temporomandibular joint (TMJ) complaints in a large group of divers. Methods: This survey study included scuba divers older than 18. The questionnaire contained 25 questions about the demographic characteristics of divers, dental health behaviors, and diving-related dental, sinus and/or temporomandibular joint pain. Results: The study group consisted of 287 instructors, recreational and commercial divers (mean age 38.96 years) (79.1% males). A total of 46% of divers reported a frequency of tooth brushing less than twice a day; 28% never receive a routine dental examination; 22.6% experienced dental pain after and/or during diving, mostly in the upper posterior teeth (40%); 17% required dental treatment; 77% of these cases are restoration fracture. TMJ symptoms after diving were statistically significantly higher in women (p=0.04). Jaw and masticatory muscle pain in the morning (p≺0.001) limitation of mouth opening (p=0.04) and joint sounds in daily life (p≺0.001) were recorded as exacerbated after diving; the results were found to be statistically significant. Conclusion: In our study, the localization of barodontalgia was consistent with the distribution of caries and restored tooth areas in the literature. Dive-related TMJ pain was also more common in those with pre-dive problems such as bruxism and joint noise. Our results are important to remind us of the necessity of preventive dentistry practices and early diagnosis of problems in divers. Divers should take personal precautions, such as brushing their teeth twice a day and avoiding the need for urgent treatment. The use of a personalized mouthpiece is also recommended for divers to prevent dive-related temporomandibular joint diseases.

Orofacial problems in scuba diving: prevalence and prevention-a large-scale survey among civilian divers in France.

Self-contained underwater breathing apparatus (SCUBA) diving is becoming widely democratized among hobbyist practitioners. It can cause orofacial problems, mostly linked to pressure changes. The aim of this study was to assess the prevalence of these problems and to analyze civilian divers' behavior about their dental prevention in France, via a cross-sectional study. Data from 1015 French civilian divers were collected via a nationwide online questionnaire in which participants indicated information concerning orofacial experienced problems during their diving activity, and their medical preventive habits. As results, oral manifestations were experienced by 25.2% of the divers, including barodontalgia (10.8%), mouth syndrome (13.4%), gum pain (2.8%) and dental fractures caused by barotrauma (3.7%) or shocks (1.9%). Mouth syndrome was more frequent among women (18.6%) and divers aged between 18 and 34 years (18.9%). The prevalence of dental fractures increased significantly with age. High diving level was associated with more frequent barodontalgia (17.5%), gum pain (7%) and barotrauma (7.6%). Among respondents, 43.5% completed a dental examination before a diving season and showed fewer oral problems during their scuba diving practice than those who did not. In conclusion, oral problems in scuba diving represent frequent events that can compromise the safety of divers. Despite awareness rising, there is a lack of recourse to the dentist. This leads to incomplete information, especially concerning the preventive means available to divers.

Unique challenges in naval military dentistry.

Divers are regularly exposed to a unique and changing environment that dentists must consider when treating such patients. This review focuses around two case studies encountered in naval dentistry: (i) diving barotrauma (pressure-induced injury related to an air space); and (ii) scuba diving mouthpiece-related oral conditions. Each condition is described by its effect on the oral cavity and in particular the teeth. Then we generally review the latest literature on the different effects of scuba diving on the diver's head, face and oral regions and emphasize methods of dental disease prevention, diagnostic tools and treatment guidelines.

SCUBA Diver's Knee: A Case Report.

ABSTRACT: With more than 9 million recreational certified self-contained underwater breathing apparatus divers in the United States, clinicians should be aware of the unique diving-related injuries. One of the most common diving-related injuries is type 1 decompression sickness, or "the bends." The bends commonly manifest as localized joint pain, most often occurring within 24 h of surfacing and resolving over the following 1 to 2 d. We report a unique case of a patient who experienced an exacerbation of musculoskeletal joint pain following initial recovery. This 35-year-old man had nearly complete resolution of his joint pain following the bends, then developed severe right knee pain with swelling after a high-volume lower body workout. Following unremarkable imaging and unsuccessful conservative treatment, ultrasound-guided aspiration of his right knee was performed, which resolved the patient's symptoms. This case highlights a unique presentation of the bends and demonstrates a potentially beneficial treatment if recurrence of the bends is suspected.

Hyperbaric oxygen for decompression sickness.

Decompression sickness (DCS, "bends") is caused by formation of bubbles in tissues and/or blood when the sum of dissolved gas pressures exceeds ambient pressure (supersaturation). This may occur when ambient pressure is reduced during any of the following: ascent from a dive; depressurization of a hyperbaric chamber; rapid ascent to altitude in an unpressurized aircraft or hypobaric chamber; loss of cabin pressure in an aircraft; and during space walks.

Balloon Eustachian tuboplasty in a professional Navy SEAL diver: case report.

Middle ear barotrauma due to dilatory Eustachian tube dysfunction (ETD) is probably the most common medical disorder related to diving. Moreover, ETD makes divers prone to other diving-related accidents, including inner ear barotrauma and alternobaric vertigo. Until the development of Eustachian tube balloon dilation no diving-compatible surgical options existed to effectively and safely prevent recurrence. We present a case of an Israeli Navy SEAL diver who dives in extreme strenuous combat-related closed-circuit rebreather (CCR) dives. Due to repeated middle ear barotrauma, the patient underwent Eustachian tube balloon dilation of the affected side. Following surgery, the patient returned to both CCR and scuba dives but still suffered from middle ear symptoms and repeated barotrauma hence was eventually disqualified from further combat diving.

A case of a critically injured diver with multiorgan failure and severe pulmonary overinflation syndrome in a resource-limited setting.

A diver practicing controlled emergency ascent training on the island of Guam suffered bilateral pneumothorax, pneumomediastinum, coronary arterial gas embolism, and developed multiple organ dysfunction syndrome. Due to limitations of available resources he was medically managed in the intensive care unit until he could be transferred to University of California San Diego for definitive management. We provide an account of our management of the patient, the pathophysiology of injury as well as a review of the safety of recreational diving skills training, current standards of practice and potential pitfalls when considering proper management of a critically injured diver.

Effect of Long-Term Diving on the Morphology and Growth of the Distal Radial Epiphyseal Plate of Young Divers: A Magnetic Resonance Imaging Study.

OBJECTIVE: To investigate the effects of long-term diving on the morphology and growth of the distal radial epiphyseal plate in young divers. STUDY DESIGN: Cohort study. SETTING: Guangzhou Sport University. PARTICIPANTS: Thirty-eight professional divers, aged 10 to 17 years, and 25 age-matched volunteers. INTERVENTIONS: Each subject received a physical examination at the beginning of the study and underwent bilateral magnetic resonance imaging of the wrist. The divers were divided into 2 groups depending on the status of the epiphyseal plate: group A (positive distal radial epiphyseal plate injury) and group B (no positive distal radial epiphyseal plate injury). A third group, group C, consisted of the 25 volunteers. MAIN OUTCOME MEASURES: The frequency of distal radial epiphyseal plate injury and the thickness of the distal radial epiphyseal plate were analyzed across the 3 groups. RESULTS: Twenty-nine cases (29/76, 38.15%) of distal radial epiphyseal plate injury were observed in 20 divers (20/38, 52.63%). The incidence of injury to the right hand was higher than that for the left (P = 0.009). There were statistically significant differences (P = 0.000) among the 3 groups in terms of epiphyseal plate thickness; group A > group B > group C. CONCLUSIONS: Distal radial epiphyseal plate injury is common in divers, and more injuries are seen in the right hand. Moreover, growth of the radius was impaired in divers relative to controls. We consider that loading during diving may influence growth of the epiphyseal plate in either a transient or permanent manner.

Epidemiology of morbidity and mortality in US and Canadian recreational scuba diving.

OBJECTIVES: This study investigates morbidity and mortality suffered by divers in the USA and Canada. STUDY DESIGN: Prospectively recruited probability-weighted sample for estimating the national burden of injury and a weighted retrospective survey for estimating exposure. METHODS: The National Electronic Surveillance System and Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP) were searched for scuba diving injuries. The Divers Alert Network diving fatality database was searched for deaths, and Sports and Fitness Industry Association estimates for diving were obtained from annual surveys. RESULTS: In the USA, there were an estimated 1394 emergency department (ED) presentations annually for scuba-related injuries. The majority (80%) were treated and/or released. There were an estimated 306 million dives made by the US residents 2006-2015 and concurrently 563 recreational diving deaths, a fatality rate of 0.18 per 105 dives and 1.8 per 105 diver-years. There were 658 diving deaths in the US 2006-2015 and 13,943 ED presentations for scuba injuries, giving a ratio of 47 diving deaths in the USA for every 1000 ED presentations. There were 98 cases of scuba-related injuries identified in the CHIRPP data. The prevalence of scuba-related injuries for patients aged 3-17 years was 1.5 per 105 cases, and the prevalence of scuba-related injuries to patients 18-62 years was 16.5 per 105 cases. DISCUSSION: In Canada and the USA, only one out of every 10,000 ED presentations is due to a scuba-related injury. That there are 47 deaths for every 1000 ED presentations for scuba injuries speaks to the relatively unforgiving environment in which scuba diving takes place. For 1.8 deaths per million recreational dives, mortality in scuba diving is nonetheless relatively low.

Cervicocranial artery dissection and scuba diving: Is there a link or is it serendipity?

INTRODUCTION: Numerous reports have documented cervicocranial artery dissection (CCAD) associated with scuba diving. The question remains as to whether there are risk factors unique to scuba diving related to the occurrence of CCAD. OBJECTIVES: This article aims to perform an examination of the reported cases to demonstrate any commonality among the injured divers and association with known risk factors for CCAD. METHODS: A PubMed search was performed utilizing the key words: carotid artery dissection, dissection, arterial dissection, cranial artery dissection, scuba, diving, scuba diving. Articles including reports, reviews, trials, case series, and letters were considered. Each report was critically dissected for information specific to the dive itself and the diver and analyzed for similarities and consistency with known risks. RESULTS: Twelve (12) reports of CCAD associated with scuba diving were identified. Activities involved with scuba diving appear to be consistent with CCAD risk factors. It is unclear if hyperbaric stress and physiological changes during a dive present specific risk. Trauma - e.g., environmental protection and activities associated with diving - was identified as a common risk factor in all cases. Ten (10) cases involved arteries at anatomic sites commonly associated with dissections. Seven divers documented to have dive profiles suspicious of decompression sickness were identified. CONCLUSIONS: There appears to be a correlation with minor traumas that occur with diving and CCAD. The inconsistency of the dive-related specific information reported makes it impossible for investigation of hyperbaric stress-related risk factors for CCAD to be analyzed.

Incidence of otic barotrauma in Canadian Armed Forces shallow-water diver candidate students 2011-2015.

INTRODUCTION: While otic barotrauma (OBT) is a common condition experienced by divers, data related to military divers is limited. This study aimed to determine the incidence of OBT in Canadian armed forces (CAF) shallow-water diver (SWD) students trained through the Fleet Dive Unit (Atlantic) (FDU[A]) between 2011-2015. METHODS: A retrospective cohort evaluation was performed. The study group consisted of all SWD candidates who embarked on an SWD course through FDU(A) between 2011-2015. A total of 241 subjects comprised the final data analysis. RESULTS: A total of 56 individuals (23.2%) suffered 60 instances of OBT, yielding an incidence density rate of 8.68 per 1,000 person-days on course. A total of 73 diving days (10.44 per 1,000 planned person-course days, or 4.87 diving days per course) were lost due to OBT. Of the reported OBT cases, 18% resulted in cessation of training, 72% in temporary removal from diving. There was no statistically significant association between sex, history of environmental allergies, previous dive qualification, age or rank and the development of OBT. CONCLUSIONS: This study reveals that OBT is prevalent among CAF SWD candidates, with operational impact due to missed diving days. This study is limited, and further prospective study is recommended.

Tympanometric evaluation of Eustachian tube function in Polish scuba divers.

BACKGROUND: Scuba divers are subjected to relatively high ambient pressures while descending. Equalizing maneuvers (e.g., Valsalva) are necessary to open the Eustachian tube (ET) and allow air into the middle ear (ME) cavity. Insufficient opening of the ET leads to ME barotrauma, which is the most common injury related to scuba diving. The study aims were to assess the incidence of ME barotrauma and to compare tympanometric parameters and stapedial reflexes in scuba divers and non-diving individuals. MATERIAL AND METHODS:: 60 scuba divers participated in the study; control consisted of 90 non-diving volunteers without a history of otolaryngologic problems. All participants were examined with the use of otoscopy and tympanometry with evaluation of ipsilateral stapedial reflexes. The group studied was surveyed regarding occurrence of ME barotrauma and diving competence. RESULTS: 51.7% of the divers experienced ME barotrauma, the most common symptoms being earache and hearing loss. Comparison of the group studied and control revealed significantly lower ME pressure and compliance in scuba divers. In scuba divers with ME barotrauma, longer time from injury correlates directly with greater ME pressure and compliance, indicating tissue recovery. At 4,000Hz 100dB percentage of present stapedial reflexes among scuba divers was significantly lower than in controls; moreover, a greater number of dives correlated inversely with percentage of present stapedial reflexes at 4000Hz 100dB. The reduced thresholds at high intensities suggest a negative effect of scuba diving on hearing. CONCLUSIONS: ME pressure and compliance, however still within the norm, are significantly lower in scuba divers than in non-diving healthy volunteers. This may be attributed to a subclinical form of barotrauma.

Sphenoid sinus barotrauma in diving: case series and review of the literature.

About 50% of scuba divers have suffered from barotrauma of the ears and about one-third from barotrauma of paranasal sinuses. The sphenoid sinuses are rarely involved. Vital structures, as internal carotid artery and optic nerve, adjoin the sphenoid sinus. Thus, barotrauma could lead to serious neurologic disorders, including blindness. After searching the literature (Medline) and other sources (Internet), we present some cases of sphenoid sinus barotrauma, because these injuries may be underreported and misdiagnosed due to the lack of awareness and knowledge. Therefore, information is provided, e.g. on anatomical and pathophysiological features. Divers and physicians should have in mind that occasional headache during or after diving sometimes signals serious neurological disorders like vision loss. We show that injuries can develop from both negative and positive pressures in the sinuses. Because visual recovery depends on prompt diagnosis and proper therapy, physicians like otolaryngologists, ophthalmologists and neurologists need to closely collaborate.

Injury and illness in aquatic sport: how high is the risk? A comparison of results from three FINA World Championships.

BACKGROUND: Epidemiological information on injury/illness is required to develop effective injury prevention strategies. AIM: To assess the frequency and characteristics of injuries/illnesses (1) in the 4 weeks prior to and (2) during the Fédération Internationale de Natation (FINA) World Championships 2015 compared with 2013 and 2009. METHOD: (1) Athletes answered a retrospective questionnaire, and (2) the medical staff reported injuries/illnesses prospectively during the championships. RESULTS: (1) A quarter of responding athletes reported symptoms in the 4 weeks prior to the championships. More than half of all affected athletes presented with substantial severity, 80% took medication, 70% had overuse injuries and 30% did not modify their training regime despite symptoms. At the start of the championships, 70% of affected participants were still symptomatic. (2) During the championships, injury and illness incidence was 12.9 per 100 athletes. The most common injuries were shoulder sprains (5.7%) and muscle cramps of the lower back (5.7%). The most common illnesses were infections of the respiratory (33.9%) and gastrointestinal tract (23.5%). Risk factors included discipline and age, but not gender. Incidence was highest in athletes competing in high diving (HD), water polo (WP) and diving (DIV) for injuries, and WP and swimming (SW) for illnesses. The significantly higher incidence of injuries and illnesses at the FINA World Championships 2015 compared with 2013 and 2009 was most probably due to a similarly improved response rate of the medical staff. CONCLUSIONS: In aquatic sports, surveillance and health promotion should focus on prevention of out-of-competition overuse injuries and athlete education.

Traumatic Pneumothorax Associated With Penetrating Neck Injury Caused by a Stingray: A Case Report.

We describe a patient with missed traumatic pneumothorax due to penetrating neck injury that was presumably caused by a stingray while diving. The barb can result in significant injuries to deep structures and organs despite a deceptively small entrance wound. This case underscores the importance of performing a thorough examination and having a high suspicion of distant injury in patients with penetrating neck injuries.

Competitive Diving Principles and Injuries.

Competitive diving is a sport that has evolved over time to become an admired present-day aquatic sport, especially in the Olympic setting. Despite its popularity, sparse research has been written as it applies to our understanding of competitive diving injuries. This article attempts to discuss common principles of competitive diving as they relate to the sport, especially as it relates to the extreme physical forces encountered by the diver and also the repetitive nature of diving. Next, these principles will be applied in the context of musculoskeletal and medical diving specific injuries.

[Epidemiology of traumatic spinal cord injury in Gran Canaria]. / Epidemiología de la lesión medular de origen traumático en Gran Canaria.

OBJECTIVE: To evaluate the epidemiological and clinical trends in acute traumatic spinal cord injuries. MATERIAL AND METHODS: A retrospective study was conducted of traumatic spinal cord injury patients in Gran Canaria (Canary Islands, Spain) from 2000 to 2014. Demographic and spinal injury severity trends were analysed by year of injury grouped into 3 periods: 2000-2005, 2006-2010, and 2011-2014. RESULTS: The sample included 141 patients. The mean incidence for the entire period was 12 cases/million/year. There was a decrease in cases in the second and third period. While the male/female ratio was 3.8/1 and was maintained in all periods, the mean patient age increased from 38.8 in 2000-5 to 54.5 years in 2011-4 (P<.05). Falls have been the leading cause of spinal cord injury (48.2%), followed by traffic accidents (37.6%). Falls have increased, especially in the older population. Incomplete tetraplegia has been the most prevalent group (30.5%). A vertebral fracture was suffered by 70.3% of all patients, with 93.2% of them requiring surgery. CONCLUSIONS: There has been a decrease in the incidence of traumatic spinal cord injury in recent years. The target population has changed, and the older population is currently the most affected. This reality suggests the need to change the local prevention campaigns for spinal cord injury in the elderly.