The effect of total compression time and rate (slope) of compression on the incidence of symptomatic Eustachian tube dysfunction and middle ear barotrauma: a Phase II prospective study.

Eustachian tube dysfunction (ETD) and middle ear barotrauma (MEB) are common reported complications during hyperbaric oxygen treatment. Our Phase I study data was the first to demonstrate a statistically significant decrease in the occurrence of symptomatic ETD and MEB. The Phase I Trial suggested the total time interval and rate (slope) of compression (ROC) may be a determining factor in ETD and MEB. This Phase II study investigates an optimal rate of compression to reduce ETD and MEB when considering each multiplace treatment (with multiple patients) as the unit of observation as a group, rather than for each individual patient. Data were collected prospectively on 1,244 group patient-treatment exposures, collectively including 5,072 individual patient-treatment/exposures. We randomly assigned patient-treatment group exposures to four different time interval and rate (slope) of compression. These compression rates and slopes were identical to those used in the Phase I trial. All patients experiencing symptoms of MEB requiring compression stops were evaluated post treatment for the presence of ETD and MEB using the O'Neill Grading System (OGS) for ETD. Data were analyzed using the IBM-SPSS statistical software program. A statistically significant decrease in the number of compression holds was observed in the 15-minute compression schedule, correlating to the results observed in the Phase I trial. The 15-minute linear compression profile continues to demonstrate the decreased need for patient symptomatic compression stops (as in the Phase I trial) using a USN TT9 during elective hyperbaric oxygen treatments in a Class A multiplace hyperbaric chamber. Trial Registration: ClinicalTrials.gov Identifier: NCT04776967.

The use of oxygen hoods in patients failing on conventional high-flow oxygen delivery systems, the effects on oxygenation, mechanical ventilation and mortality rates in hypoxic patients with COVID-19. A Prospective Controlled Cohort Study.

INTRODUCTION: Efforts to meet increased oxygen demands in COVID-19 patients are a priority in averting mechanical ventilation (MV), associated with high mortality approaching 76.4-97.2%. Novel methods of oxygen delivery could mitigate that risk. Oxygen hoods/helmets may improve: O2-saturation (SaO2), reduce in-hospital mechanical ventilation and mortality rates, and reduce length of hospitalization in hypoxic Covid-19 patients failing on conventional high-flow oxygen delivery systems. METHODS: DesignProspective Controlled Cohort Study. SettingSingle Center. ParticipantsAll patients admitted with a diagnosis of COVID-19 were reviewed and 136/347 patients met inclusion criteria. Study period3/6/2020 to 5/1/2020. 136 participants completed the study with known status for all outcome measures. Intervention or exposureOxygen hoods/helmets as compared to conventional high-flow oxygen delivery systems. MAIN OUTCOME(S) AND MEASURE(S): 1) Pre and post change in oxygen saturation (SaO2). 2) In-hospital Mechanical Ventilation (MV). 3) In-hospital Mortality. 4) Length of hospitalization. RESULTS: 136 patients including 58-intervention and 78-control patients were studied. Age, gender, and other demographics/prognostic indicators were comparable between cohorts. Oxygen hoods averted imminent or immediate intubation/MV in all 58 COVID-19 patients failing on conventional high-flow oxygen delivery systems with a mean improvement in SaO2 of 8.8%, p < 0.001. MV rates were observed to be higher in the control 37/78 (47.4%) as compared to the intervention cohort 23/58 (39.7%), a difference of 7.7%, a 27% risk reduction, not statistically significant, OR 95%CI 0.73 (0.37-1.5). Mortality rates were observed higher in the control 54/78 (69.2%) as compared to the intervention cohort 36/58 (62.1%), a difference of 7.1%, a 27% risk reduction, not statistically significant OR 95%CI 0.73 (0.36-1.5). CONCLUSION: Oxygen hoods demonstrate improvement in SaO2 for patients failing on conventional high-flow oxygen-delivery systems and prevented imminent mechanical ventilation. In-hospital mechanical ventilation and mortality rates were reduced with the use of oxygen hoods but not found to be statistically significant. The oxygen hood is a safe, effective oxygen-delivery system which may reduce intubation/MV and mortality rates. Their use should be considered in treating hypoxic COVID-19 patients. Further research is warranted. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04407260.

Proof of concept study using a modified Politzer inflation device as a rescue modality for treating Eustachian tube dysfunction during hyperbaric oxygen treatment in a multiplace (Class A) chamber.

Introduction: Eustachian tube dysfunction (ETD) and middle ear barotrauma (MEB) are the most common adverse effects of hyperbaric oxygen (HBO2) treatments. Patients practice equalization maneuvers to prevent ETD and MEB prior to hyperbaric exposure. Some patients are still unable to equalize middle ear pressure. This ETD results in undesirable consequences, including barotrauma, treatment with medications or surgical myringotomy with tube placement and interruption of HBO2. When additional medications and myringotomy are employed, they are associated with additional complications. Methods: A device known as the Ear Popper® has been reported to reduce complications from serous otitis media and reduce the need for surgical interventions (myringotomy). Patients unable to equalize middle ear pressure during initial compression in the hyperbaric chamber were allowed to use the device for rescue. All hyperbaric treatments were compressed using a United States Navy TT9, or a 45-fsw hyperbaric treatment schedule. Patients with persistent ETD and the inability to equalize middle ear pressure were given the Ear Popper upon consideration of terminating their treatment. Results: The Ear Popper allowed all patients to successfully equalize middle ear pressure and complete their treatments. Conclusion: This study substantiates the use of this device to assist in allowing pressurization of the middle ear space in patients otherwise unable to achieve equalization of middle ear pressure during HBO2 treatment in a multiplace chamber.