Use of Dexmedetomidine in Transfemoral Transcatheter Aortic Valve Implantation (tf-TAVI) Procedures

Introduction: Dexmedetomidine is a highly selective alpha-2 adrenoreceptor agonist without any effect on the GABA receptor. Its sedative, anxiolytic, analgesic, and sympatholytic activities together with opioid-sparing effects make it suitable for short- and long-term sedation in the intensive care setting. We report our experience with dexmedetomidine use during transfemoral transcatheter aortic valve implantation (TAVI) procedure as an alternative to general anesthesia.

Methods: This is a retrospective analysis of high-risk patients undergoing dexmedetomidine infusion for the transfemoral TAVI procedure between July 2017 and October 2019. The primary outcome parameters were hemodynamic: heart rate (HR), mean arterial pressure (MAP); respiratory oxygen saturation (SpO), pH, partial pressure of arterial oxygen (PaO), partial pressure of arterial carbon dioxide (PaCO), and sedation level (Richmond Agitation-Sedation Scale, RASS). The frequency of conversion to general anesthesia and the need for sedative "rescue therapy" were secondary endpoints. We also reported the overall anesthetic management and the incidence of intra- and postoperative complications.

Results: Eighty-five patients were evaluated (age 81.58 ± 5.23 years, 36.5% men, 63.5% women). High comorbidity, according to the Society of Thoracic Surgeons Predicted Risk of Mortality (STS PROM). The patients' hemodynamic functions were kept normal. Complications such as cardiac arrest occurred in four patients; orotracheal intubation and cardiopulmonary resuscitation were necessary. Atrioventricular block occurred in nine patients. Respiratory parameters were maintained stable. Complications such as apnea, hypoventilation, and hypoxemia did not occur. All patients had RASS scores above or equal to 0 and - 1. No patient required rescue midazolam or fentanyl. No conversion to general anesthesia in patients sedated with dexmedetomidine was observed in the absence of hemodynamic complications caused by the surgical technique.

Conclusion: In this series, sedation with dexmedetomidine for TAVI procedures with femoral access was proven effective and safe. Dexmedetomidine may be a valid alternative to general anesthesia in high-risk older patients undergoing transfemoral TAVI.