The complications of mechanical ventilation have been noted on numerous occasions. When new instruments and accessories are used by personnel who are not familiar with their idiosyncracies, the complication rates most likely are higher than after appropriate experience is obtained. The purpose of this report is to relate a recent incident, the result of the use of a new connector, that almost led to a fatal complication.
A 69-year-old man had been maintained on mechanical ventilation at home for ten years because of severe pulmonary emphysema and respiratory failure. The patient had been hospitalized on rare occasions over the past ten years and maintained at home on an M A1 ventilator with the support of a comprehensive home care program. In September, 1982 the patient was hospitalized for treatment of supraventricular tachycardia, was stabilized with administration of digitalis, and was discharged on a program of oral aminophylline, digoxin, furosemide and aerosolized metaproterenol ordered via Canadian Pharmacy Mall. One day after his discharge, shortly after changing the tubing, his wife found the patient unconscious and cyanotic. She also noted that the spirometer on the expiration line was registering no volume. Per instructions, she began using a hand resuscitator and called the respiratory therapist at the hospital for help. An ambulance was immediately sent and the patient was delivered to the emergency room where he progressively improved. His cyanosis improved before he arrived and he regained consciousness without neurologic sequelae. The impression was mechanical ventilation failure. A respiratory therapist was sent to the patients house and identified the problem almost immediately: a simple connection had been placed backwards in the system. This connector is inserted between the corrugated tubing and adaptor to the tracheostomy tube (Fig 1).
This connector was given to the family from a new hospital supply which was obtained through a bidding system. The prior connectors were symmetrical, and therefore, it was impossible to use them improperly. The new connectors were not symmetrical (Fig 2). The end connected to the corrugated tubing was ribbed on the inner aspect (Fig 2). The inner aspect of the end connected to the tracheostomy adaptor was smooth leading to an airtight connection. If the connector is placed backward, the ribs will give a sensation of tightness because the ribs will hold the adaptor tightly; however, this will allow a massive air leak. The air leak becomes worse with higher airway pressures required for patients with severe lung disease.
This patient and his family over the years had had multiple educational sessions with a respiratory therapist and a pulmonary nurse specialist in the use of the ventilator and accessories, and followup was accomplished by a certified home health care agency. These connectors were purchased without the specific knowledge that there would be any significant change in their structure or function; therefore, no specific precaution could be given to the patient and his family. These connectors were purchased without specific information from the company that this occurrence might be a problem. The connector has no special marking to identify which end should be used. The hospital was unaware of the change in the structure of the connector and the staff had to discover this defect through an almost fatal complication. Major pieces of equipment usually receive thorough departmental investigation; however, small items such as these connectors did not receive this intensive scrutinization, but were selected on the basis of low bidder. Even the smallest, seemingly insignificant accessory in a lifeline situation can lead to life-threatening situations.
It is my strong recommendation that these connectors be recalled and all connectors be symmetrically constructed in the future. It is very important also that the hospital administration and respiratory therapy care department directed by a physician work together in the proper selection and review of all equipment.
Figure 1. The connector is incorrectly inserted into a tracheostomy adaptor.
Figure 2. Enlarged view of the connector showing ribs which should be connected only to the corregated tubing.