[Prolonged wound healing after perforating keratoplasty. CPAP hyperbaric ventilators for sleep apnea as a risk...

Nasal hyperbaric respiration devices used at night to counteract sleep apnea may represent a concealed cause of delayed superficial wound healing following perforating keratoplasty. We report the cases of two patients whose respirators produced a continuous flow of pressurized air (nCPAP) onto the operated eyes, leading to conjunctival hyperemia, recurrent corneal erosion, infiltration of the puncture track and the cornea, and superficial punctate keratopathy. Microbiological investigation revealed no clearly identifiable pathogens. Healing improved consistently only after the pressurized air system had been modified so that no air escaped from the nostrils and the patients had been instructed in disinfection of the moisturizing system.