Purpose: Different sedation regimens have been described for use during transfemoral transcatheter aortic valve implantation (tf-TAVI) for treatment in patients with severe aortic stenosis. The purpose of this study was to compare dexmedetomidine (DEX) with a combination of propofol-opioid (PO) with respect to periprocedural gas exchange and hemodynamic support.
Methods: Data from a cohort of patients sedated with either DEX or PO for tf-TAVI were retrospectively analyzed from a prospectively maintained TAVI registry. Operative risk was determined from comorbidities and risk scores. Periprocedural partial pressure of carbon dioxide (PaCO2) was chosen as the primary endpoint. Other differences in gas exchange, need for catecholamine therapy, the frequency of conversion to general anesthesia, and need for sedative "rescue therapy" (in DEX patients) were secondary endpoints. Inverse probability of treatment weighting (IPTW) was used for analysis to minimize any selection bias.
Results: Of the 297 patients (140 PO, 157 DEX) included, the median [interquartile range] periprocedural PaCO2 values of DEX patients were significantly lower than in PO patients (40 [36-45] mmHg vs 44 [40-49] mmHg, respectively; median difference -4 mmHg; 95% confidence interval, -5 to -3 mmHg; P < 0.001). Hypercapnia (PaCO2 > 45 mmHg) was significantly less frequent in DEX patients compared with the PO group (25% vs 42%, respectively; P = 0.005). Vasopressor support was more frequent in the PO group compared with DEX (68% vs 25%, respectively; P < 0.001). Conversion to general anesthesia was not different between groups (9%, PO vs 3%, DEX; P = 0.051). Additional sedatives/opioids were required in 25 (16%) of the DEX patients.
Conclusions: In sedated TAVI patients, DEX was associated with lower PaCO2 values and reduced requirements for vasopressor support, making it a promising alternative to PO for sedation during TAVI.
Trial registration: www.ClinicalTrials.gov (NCT01390675). Registered 11 July 2011.