Undersea & Hyperbaric Medicine : Journal of the Undersea and Hyperbaric Medical Society, Inc

OBJECTIVE: The presentation of a novel prospective treatment for scenarios where bubble presence in the bloodstream poses a clinical risk. The method relies on generating resonant acoustic standing waves within a limb to non-invasively accelerate the dissolution of bubbles present in the bloodstream via bubble rupture. Additionally, a preliminary assessment of the effects of the resonant acoustic waves and bubble rupture events on red blood cell viability is provided. METHODS: Two semicircular piezoelectric (PZT) transducers electrically connected to each other were assembled around a small-girth segment of a rear thigh removed from a swine specimen...

We tested the hypotheses that self-paced aerobic exercise performance is reduced following four hours of cold-water immersion when breathing air and further reduced when breathing 100% oxygen (O2). Nine healthy adults (four women; age 24 ± 3 years; body fat 17.9 ± 6.4%; VO2max 48±9 mL • kg • minute⁻¹) completed three visits: a no-immersion control trial and two experimental trials consisting of a four-hour cold-water immersion (20.1±0.3°C) either breathing air (FIO2 = 0...

INTRODUCTION: Since the U.S. Navy transitioned from the MK10 to the MK11 submarine escape and immersion equipment (SEIE), there has been an increase in the incident rate of pulmonary barotrauma during submarine escape training. This study compares the ascent rate profiles of the MK10 and MK11 SEIE to determine if ascent rate differences between the escape suits are associated with increased pulmonary barotraumas. METHODS: Buoyant ascent rates of the MK10 and MK11 SEIE were compared using weighted manikins equivalent to the 1st, 50th, and 99th percentile body weight of a submariner...

INTRODUCTION: Hyperbaric oxygen (HBO₂) improves outcome in patients with acute carbon monoxide (CO) poisoning, but optimal dose/timing are unknown. In this double-blind, sham-controlled randomized trial, we compared neuropsychological sequelae at six weeks and six months in patients receiving three HBO₂ sessions or one HBO₂ session and two sham chamber sessions after acute CO poisoning. METHODS: After completing one HBO₂ session (3.0 ATA, 60 minutes, 2...

Cardiomyopathy is a known but rare sequelae of diving-related cerebral arterial gas embolism (CAGE). In previously reported cases, patient findings have been consistent with takotsubo cardiomyopathy (TCM) per the revised Mayo Clinic's diagnostic criteria. A lesser-known variant of stress-related cardiomyopathy is neurogenic stunned myocardium (NSM), which occurs after a neurological event such as subarachnoid hemorrhage and typically presents in younger patients. Presentation tends to differ slightly to TCM with non-specific left ventricular dysfunction and T wave inversions...

Studies evaluating the hearing function of professional divers have yielded mixed results. In this study, we aimed to observe the effect of diving on hearing function by comparing the audiometry of experienced divers with a non-diver control group. Secondly, we aimed to compare the hearing function among divers according to the diving years and the number of dives in terms of diving exposure. Experienced divers who applied to the University of Health Sciences Gűlhane Training and Research Hospital Underwater and Hyperbaric Medicine Department between 2017-2021 for periodic fitness to dive examinations were included in our study...

OBJECTIVE: This study quantifies the change in intraocular pressure (IOP) secondary to wearing neck seals in scuba diving drysuits. Previous work demonstrates significant pressures exerted by these seals; we hypothesize that they would. METHODS: IOP was measured in 33 divers before and while wearing a drysuit using rebound tonometry. The drysuit neck seal pressures were measured using a manometer. A paired two-sample t-test was used to compare IOP before and after drysuit donning...

A recent review suggested that the measure K = t² x pO₂ [4.57] (t is exposure time in h, pO in atm) should replace unit pulmonary toxic dose (UPTD) as an exposure index for pulmonary oxygen toxicity (POT) in surface-oriented diving. K would better predict reduction in vital capacity (VC) during exposure and allow prediction of recovery. Although K is more accurate estimating VC changes than UPTD, the calculation of K is more extensive, particularly when estimating hyperoxic exposure for dives with multiple pO₂ segments...

The aim of this study was to investigate the effect of hyperbaric oxygen (HBO2) administration during cold ischemic time to organs removed from donors before kidney transplantation. A total of 24 rats were divided into three groups: Group 1 was the control group, Group 2 received 60 minutes of HBO2 at 2.5 atmospheres absolute, and Group 3 received 120 minutes of 2.5 ATA HBO2. The renal artery was entered with a polyethylene catheter and perfused with a standard organ preservation solution. Falcon tubes containing organs obtained from rats in Groups 2 and 3 were placed in a box supported by ice blocks...

A 47-year-old active-duty Navy diver with a complicated past medical history which resulted in his designation as not physically qualified (NPQ) for diving duty in 2016 presented on 07 May 2021 complaining of left-sided blurred vision. On exam by the attending undersea medical officer, he was found to have a left upper inner and upper outer quadrant visual field defect and a central scotoma. Urgent referral to ophthalmology ruled out retinal detachment but resulted in an initial diagnosis of a left branch retinal artery occlusion without embolus...

RATIONALE: Cerebral arterial air embolism is a rare but potentially fatal complication of computed tomography (CT) guided lung biopsy. Hyperbaric oxygen (HBO2) is the first line of treatment for arterial gas embolism and needs to be administered immediately after the event. Early HBO2 can reduce the mortality rate of cerebrovascular air embolism. PATIENT CONCERNS: A 65-year-old woman was diagnosed with a pulmonary nodule with a diameter of approximately 0.8 cm in the right lower lung...

BACKGROUND: Electronic devices remain highly restricted from use during hyperbaric oxygen (HBO2) treatment due to risk of fire in a pressurized, oxygen-rich environment. Over recent decades, point-of- care ultrasound (POCUS) has established utility in most clinical environments except hyperbaric chambers, where only heavily modified POCUS devices have been used. This study evaluated proof of concept, safety, and performance of a wireless off-the-shelf handheld POCUS device in the hyperbaric environment...

PURPOSE: To evaluate the effectiveness of hyperbaric oxygen (HBO2) therapy as a treatment for central retinal artery occlusion (CRAO). METHODS: A total of 38 patients who underwent HBO2 for non-arteritic CRAO were identified. Patients with arteritic CRAO, branch retinal artery occlusion, ophthalmic artery occlusion, and other diagnoses were excluded from the analysis. The main outcome measured was the change in visual acuity at the most recent follow-up exam compared to the visual acuity at presentation before the initiation of HBO2 therapy...

No abstract text is available yet for this article.

BACKGROUND: This study sought to investigate therapeutic effects of hydrogen-rich saline (HRS) combined with hyperbaric oxygen (HBO2) in an experimental rat model of acute lung injury (ALI). METHOD: Forty male Sprague-Dawley rats were randomly divided into sham, LPS, LPS + HBO2, LPS + HRS, and LPS + HBO2 + HRS groups. After an intratracheal injection of LPS-induced ALI, the rats were given a single-agent HBO2 or HRS or HBO2 + HRS treatment. The treatments were continued for three days in this experimental rat model of ALI...

PURPOSE: Sudden sensorineural hearing loss (SSNHL) is a time-sensitive urgent condition. The aim of this study was to evaluate the frequency of hearing improvement in patients with idiopathic SSNHL who only received hyperbaric oxygen (HBO2) therapy within three days of symptom onset, instead of conventional corticosteroid treatment. METHODS: The medical charts of patients who experienced SSNHL between January 1, 2012, and December 31, 2021, were reviewed. The present study included all adult patients who were diagnosed with idiopathic SSNHL and started HBO2 therapy within 72 hours of symptom onset...

On November 9, 1963, a coal dust explosion occurred at the Miike Mikawa Coal Mine (Omuta, Kyushu Region of Japan). This resulted in a massive release of carbon monoxide (CO) gas that resulted in 458 fatalities and 839 victims of CO poisoning. After the accident, the Department of Neuropsychiatry, Kumamoto University School of Medicine (including the authors) immediately began to conduct periodic medical examinations of the victims. Such a long-term follow up of so many CO-poisoned patients is globally unprecedented...

INTRODUCTION: In fatal accidents during scuba diving, it is necessary to differentiate a death from primary drowning from a secondary drowning death that is primarily due to other etiopathogenetic factors. The inhalation of water can only be the end point of a series of events capable of causing the diver's exitus. This study aims to demonstrate that even low-risk heart disease in daily life become potentially fatal during scuba diving. METHODS: In this case series, we describe all cases of deaths in the course of diving that came to the observation of the Forensic Institute of the University Bari over 20 years (2000-2020)...

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...

During deep-sea freediving, many freedivers describe symptoms fairly similar to what has been related to inert gas narcosis in scuba divers. This manuscript aims to present the potential mechanisms underlying these symptoms. First, known mechanisms of narcosis are summarized while scuba diving. Then, potential underlying mechanisms involving the toxicity of gases (nitrogen, carbon dioxide and oxygen) are presented in freedivers. As the symptoms are felt during ascent, nitrogen is likely not the only gas involved...