Analysis of the cardiovascular effects of hyperbaric oxygen therapy in diabetic patients.

During hyperbaric oxygen (HBO2) therapy in humans, there are changes in cardiovascular physiology due to high pressure and hyperoxygenation. Peripheral vasoconstriction, bradycardia, and a decrease in cardiac output are observed during HBO2 therapy. These physiological effects of HBO2 therapy on the cardiovascular system are tolerated in healthy people. However, patients with underlying cardiac disease may experience severe problems during HBO2 therapy, such as pulmonary edema and death. In addition, cardiac complications may occur in patients with diabetes mellitus (DM). Therefore, HBO2 therapy may negatively affect cardiovascular physiology in patients with DM. The present study aimed to examine the cardiovascular effects of HBO2 therapy in diabetic patients. The findings of NT-ProBNP, troponin I, and electrocardiography (ECG) of diabetic patients who applied to the Ministry of Health University Gülhane Training Research Underwater and Hyperbaric Medicine Clinic were compared before and after the first HBO2 therapy session. When ECG findings were analyzed at the end of a session of HBO2 exposure, a statistically significant increase was observed in the QTc and QTc dispersion measurements (p≺0.001 and p = 0.02, respectively). In cardiac enzymes, there was a statistically significant increase in troponin I values after an HBO2 therapy session, but no statistically significant change was observed in Pro-BNP (p = 0.009, p = 0.3, respectively). Short-term exposure to HBO2 therapy had statistically significant changes in troponin I, QT, and QTc in patients with DM, which did not reach clinical significance. Despite very little evidence of cardiac dysfunction, we recommend caution in using HBO2 therapy in patients with DM and emphasize the need for further investigation of these measurements.

Hyperbaric oxygen treatment in delayed post-hypoxic encephalopathy following inhalation of liquefied petroleum gas: a case report.

Delayed post-hypoxic encephalopathy can occur after an episode of anoxia or hypoxia. Symptoms include apathy, confusion, and neurological deficits. We describe a 47-year-old male patient who inhaled gas from a kitchen stove liquid petroleum gas cylinder. He was diagnosed with hypoxic ischaemic encephalopathy 12 hours after his emergency department admission. He received six sessions of hyperbaric oxygen treatment (HBOT) and was discharged in a healthy state after six days. Fifteen days later, he experienced weakness, loss of appetite, forgetfulness, depression, balance problems, and inability to perform self-care. One week later, he developed urinary and fecal incontinence and was diagnosed with post-hypoxic encephalopathy. After 45 days from the onset of symptoms, he was referred to the Underwater and Hyperbaric Medicine Department for HBOT. The patient exhibited poor self-care and slow speech rate, as well as ataxic gait and dysdiadochokinesia. Hyperbaric oxygen was administered for twenty-four sessions, which significantly improved the patient's neurological status with only hypoesthesia in the left hand remaining at the end of treatment. Hyperbaric oxygen has been reported as successful in treating some cases of delayed neurological sequelae following CO intoxication. It is possible that HBO therapy may also be effective in delayed post-hypoxic encephalopathy from other causes. This may be achieved through mechanisms such as transfer of functional mitochondria to the injury site, remyelination of damaged neurons, angiogenesis and neurogenesis, production of anti-inflammatory cytokines, and balancing of inflammatory and anti-inflammatory cytokines.

Does diving deteriorate hearing functions?

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 Gulhane Training and Research Hospital Underwater and Hyperbaric Medicine Department between 2017-2021 for periodic fitness to dive examinations were included in our study. The control group was randomly selected from the non-diver population with similar ages and gender. The audiometry of the control group and the study group was compared. While the control group was found to be better only at 8,000 Hz in the left ear (p = 0.03), there was no difference between the study group and the control group in other frequencies and pure-tone averages. In conclusion, we did not find any evidence regarding the worsening effect of diving on the hearing functions of experienced divers. With the increased awareness of occupational safety in recent years, modern technologies, protective measures, and more conservative diving profiles may have minimized the possible adverse effects of diving on hearing function. Longitudinal studies on hearing functions in the same occupational diver groups should be conducted while observing the effect of different diving profiles and noise exposures.

Hemiplegia resulting from acute carbon monoxide poisoning.

Carbon monoxide (CO) poisoning can cause neurological complications such as movement disorders and cognitive impairment through hypoxic brain damage. Although peripheral neuropathy of the lower extremities is a known complication of CO poisoning, hemiplegia is very rare. In our case, a patient who developed left hemiplegia due to acute CO poisoning received early hyperbaric oxygen treatment (HBOT). The patient had left hemiplegia and anisocoria at the beginning of HBOT. Her Glasgow coma score was 8. A total of five sessions of HBOT at 243.2 kPa for 120 minutes were provided. At the end of the 5th session, the patient's hemiplegia and anisocoria were completely resolved. Her Glasgow coma score was 15. After nine months of follow-up, she continues to live independently with no sequelae, including delayed neurological sequelae. Clinicians should be aware that CO poisoning can (rarely) present with hemiplegia.

The changes in pulmonary functions in occupational divers: smoking, diving experience, occupational group effects.

BACKGROUND: Diving challenges the respiratory system because of the pressure changes, breathing gases, and cardiovascular effects. We aimed to analyse the long term effect of occupational diving on pulmonary functions in terms of diving experience (year), smoking history, and occupational groups (commercial divers and SCUBA instructors). MATERIALS AND METHODS: We retrospectively analysed respiratory system examination results of the experienced occupational divers who were admitted to the Undersea and Hyperbaric Medicine Department for periodic medical examination between January 1, 2013 and February 28, 2019. RESULTS: Sixty-four divers applied to our department. Candidate divers were not included in our study. The mean diving experience (year) was 13.6 ± 7.3. None of the divers complained of pulmonary symptoms. Pulmonary auscultation and chest radiography were normal in all cases. In divers with 20 years or more experience, the FEV1/FVC ratio and FEF25-75(%) was significantly lower (p < 0.001, p < 0.05, respectively). In addition, there was a statistically significant negative correlation between FEV1/FVC ratio and FEF25-75(%) and diving experience (year) (p < 0.05, r = -0.444, p < 0.05, r = -0.300, respectively). As the diving experience increase per 1 year, the FEF25-75(%) value decreases by 1.04% according to linear regression analyses. However, smoking and occupational groups did not show any significant influence on pulmonary function test parameters. CONCLUSIONS: Occupational diving seems to create clinically asymptomatic pulmonary function test changes related to small airway obstruction after long years of exposure.