Incidence and timing of hypotension after transcervical carotid artery stenting: correlation with postoperative complications.

OBJECTIVES: To assess the incidence and timing of hypotension after carotid artery stenting (CAS) and its correlation with postoperative complications.

BACKGROUND: CAS-associated postoperative hypotension has been linked to surgical morbidity and mortality, especially to stroke and cardiac complications.

METHODS: Ninety-seven consecutive patients undergoing transcervical CAS were monitored for at least 12 hr after operation. Hypotension was defined as systolic blood pressure < 90 mm Hg. Patients were divided into three groups: normal blood pressure and early (≤6 hr) and late (>6 hr) hypotension. Complications were recorded.

RESULTS: Hypotension occurred in 34% of the patients (early hypotension in 63% of them). Hypotension was recorded in 21.6% of patients during surgery and in 21.6%, 15.5%, and 1.0% at 6, 12, and 24 hr postoperatively. Bradycardia occurred in 26.8% during operation and in 25.8%, 13.4%, and 10.3% at 6, 12, and 24 hr after surgery. Intraoperative bradycardia (P = 0.01) and hypotension (P = 0.02) were predictors of postoperative hypotension. The overall rate of complications was 5% without differences between the study groups. The mean length of stay was 3, 3.6, and 2.8 days in the normotensive, early hypotension, and late hypotension groups, respectively.

CONCLUSIONS: Most postoperative hypotension episodes occurred within the first 6 hr, and more than one-third between the 6 and 12 hr post-procedure. All patients with late hypotension were asymptomatic. There was no difference in complications between the study groups. In patients undergoing ambulatory CAS, hemodynamic monitoring in the postoperative period is particularly important during the first 12 hr.