Nonrespiratory rhythmic fluctuations in systemic arterial pressure in anesthetized humans.

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.