Man on Noninvasive Positive Airway Pressure Ventilation With Throat Pain

Dentures dislodged into throat on bilevel positive airway pressure (BiPAP) ventilation can be overlooked and potentially compromise airway patency. An 81-year-old man with a history of chronic obstructive pulmonary disease (COPD) presented with increased shortness of breath and productive cough for 1 week. Inhaled bronchodilators, parenteral steroids, and BiPAP ventilation were administered for acute exacerbation of COPD complicated with acute hypercapnic respiratory failure. Fifty minutes after receiving BiPAP ventilation, his respiratory condition improved; however, he started to complain of neck pain. The patient remained intolerant to the device 3 hours later, despite receiving assurance that the discomfort might be caused by air pressure through mask ventilation. His throat did not exhibit any abnormality during visual examination. Neck radiographs were subsequently obtained and demonstrated a denture impacted in the hypopharynx. His neck pain resolved after the removal of the dislodged maxillary denture. Denture dislodgement can occur in mask ventilation and compromise airway patency if stuck in the hypopharynx or respiratory tract. Such adverse events may be overlooked on the coexistence of respiratory and pulmonary diseases. A precisely pharyngolaryngeal inspection and complete imaging studies must be performed to facilitate early identification and further retrieval intervention.

Adverse events and blinding in two randomized trials of hyperbaric oxygen for persistent post-concussive symptoms

Safety monitoring and successful blinding are important features of randomized, blinded clinical trials. We report chamber- and protocol-related adverse events (AEs) for participants enrolled in two randomized, double-blind clinical trials of hyperbaric oxygen (HBO2) for persistent post-concussive symptoms clinicaltrials.gov identifiers NCT01306968, HOPPS, and NCT01611194, BIMA), as well as the success of maintaining the blind with a low-pressure sham control arm. In both studies, participants were randomized to receive HBO2 (1.5 atmospheres absolute, >99% oxygen) or sham chamber sessions (1.2 atmospheres absolute, room air). In 143 participants undergoing 4,245 chamber sessions, chamber-related adverse events were rare (1.1% in the HOPPS study, 2.2% in the BIMA study). Minor, non-limiting barotrauma was the most frequently reported. Rarely, some participants experienced headache with chamber sessions. No serious adverse events were associated with chamber sessions. An allocation questionnaire completed after intervention revealed that the sham control arm adequately protected the blind in both trials. Participants based allocation assumptions on symptom improvement or lack of symptom improvement and could not discern intervention arm by pressure, smell, taste, or gas flow.