Failure of an epidural catheter

Good product design implies integrity when a product is in service, and is especially important in medical devices. The environment in which the product functions can vary but must be taken into account as well as its past history of environmental exposure. A case study shows how an epidural catheter fractured during childbirth, leaving the distal tip in the spinal fluid of the patient. Analysis of the proximal remains suggested that the polymer had become brittle. FTIR microscopy showed chain oxidation with UV degradation as the most likely cause of the problem. An allegation that the anaesthetist had been negligent was shown to be groundless. Many common polymers are susceptible to UV cracking, and precautions are needed during manufacture and assembly to prevent failure when the device is needed to perform a critical job.