Endotracheal tube cuff rupture during anesthesia in 2 dogs

A 15-year-old intact male dachshund dog weighing 4.3 kg and a 5-year-old intact male mixed-breed dog weighing 13.6 kg were referred for examination because of paraparesis and facial paralysis, respectively. Magnetic resonance imaging (MRI) of the thoracolumbar region and brain was performed. The dogs were premedicated with IV butorphanol, 0.2 mg/kg body weight (BW) and midazolam, 0.2 mg/kg BW. Anesthesia was induced with IV propofol, 4 to 5 mg/kg BW and maintained with sevoflurane in oxygen. The dachshund was orotracheally intubated with a 5.0-millimeter internal diameter endotracheal (ET) tube. During positioning in the MRI room, intermittent positive pressure ventilation (IPPV) was applied. The mixed-breed dog was orotracheally intubated with a 6.0-millimeter internal diameter ET tube. After inflation of the ET tube cuff, a leaking test was done by applying positive pressure ventilation. In both dogs, a distinct "popping" sound was heard when positive pressure was applied, after which air leakage from the cuff was evident. Failure to inflate the pilot balloon led to suspicion of a ruptured cuff. Reintubation was completed, both dogs remained stable during anesthesia, and no postanesthetic complications were observed. Rupture of both cuffs, which was visually confirmed, was thought to be caused by overinflation of the cuff, repeated sterilization of the ET tubes, and positive pressure ventilation. Repeated sterilization of ET tubes with ethylene oxide can alter the physical integrity of cuffs. Care should be taken not to overinflate ET tube cuffs, especially when they have been repeatedly sterilized, as cuff rupture may result in failure to provide adequate IPPV. Key clinical message: This report describes 2 cases in which ET tube cuff rupture was noted during anesthesia for MRI.