Nonrespiratory rhythmic fluctuations in systemic arterial pressure in anesthetized humans.

ABSTRACT

STUDY OBJECTIVE: To clarify the frequency of nonrespiratory rhythmic fluctuations in systemic arterial pressure (vasomotor waves) and to identify the clinical conditions in which the vasomotor waves develop in humans under anesthesia. DESIGN: Retrospective analysis of collected data. SETTING: Inpatient surgery clinic at a university hospital. PATIENTS Five hundred thirteen consecutive ASA physical status II-V patients. INTERVENTIONS: Direct arterial pressure monitoring and general anesthesia, including high-dose fentanyl, enflurane, enflurane plus fentanyl, cervical or thoracic epidural, and lumbar epidural anesthesia. MEASUREMENTS AND MAIN RESULTS: Among the anesthesia techniques used, vasomotor waves occurred most frequently in patients anesthetized with high-dose fentanyl (31.1%) and least frequently in those with high-level epidural blockade (7.4%). As a result of multiple logistic analysis, the contributing factors to the appearance of vasomotor waves were the institution of cardiopulmonary bypass (CPB) and the patient's age. It is also a novel finding that nearly one-third of the vasomotor waves developed in patients under stable hemodynamic conditions. CONCLUSIONS: Vasomotor waves are a common phenomenon in relatively high-risk patients during general anesthesia. The appearance of vasomotor waves is significantly related to CPB and patient age.