Unintended consequences of technology improvement

Introduction

Technological improvements in ventilator design may confound the diagnosis of brain death. We describe a series of patients clinically perceived to be breathing spontaneously even though they satisfied the criteria for brain death. The misdiagnosis of cerebral function in these patients delayed the diagnosis of brain death and subsequent organ donation. Resource utilization, patient/family suffering, and staff morale are all negatively impacted when this occurs.

Methods

The ventilator triggering mode was recorded in all patients. Patients were identified by the authors with a high likelihood of brain death and receiving pressure support ventilation. Patients without cranial nerve function underwent formal apnea testing.

Results

Seven patients were identified with cessation of cranial nerve function, but thought to have spontaneous breathing activity. All patients were on pressure support ventilation with flow triggering. Formal apnea testing was performed (Table 1).

Table 1

Conclusions

Improvement in triggering ventilation may confound the diagnosis of brain death. Considering the unmet need for transplantation and the negative impact of not recognizing death on families, staff, resource utilization and both patients and potential recipients of organs mandates a simple solution to eliminate these problems. We propose that in all patients being evaluated for brain death once cranial function has ceased an apnea test should be carried out promptly with the patient disconnected from the ventilator.