Outcomes with Local Anaesthesia
The development of LA blocks has provided an avenue for patients with high anaesthetic risks to have effective and long-lasting analgesia and anaesthesia and allowing the operator to perform their procedure while avoiding the risk associated with GA. Romano et al conducted a study on patients who were enlisted for a TAVI and compared the outcomes of Deep sedation (DS) against LA which were performed by interventional cardiologists. 50 patients had a femoral nerve block using ultrasound guidance with 1% lidocaine and 0.5% ropivicaine (10-12ml). 32 patients had DS with infusions of propofol (1-2 mg/kg/hr) and remifentanyl (0.1 mcg/kg/min). Both groups had no differences in baseline characteristics such as NYHA class, Left ventricular ejection fraction (LVEF), LogEuroSCORE II, and co-morbidities. Mean age in the LA group was 85.3+/-4.9 years and 84/2+/-5.7 in the DS group. 69.5% had balloon valvuloplasty prior to prosthetic valve implantation and 89% had a successful TAVI procedure. The rate of periprocedural complications did not differ between groups with the most common being minor vascular complications (20.7% in the LA group and 22% in the DS group and pacemaker implantation (14% in the LA group and 16% in the DSD group). Haemodynamic monitoring during the procedure revealed differences in the groups. With the DS group having more pronounced reduction in systolic (SBP) and diastolic blood pressure (DBP) throughout the procedure. After TAVI cardiac output rose in the LA group and stroke volume rose in both groups. Systemic vascular resistance (SVR) reduced in all stages of the procedure in the DS group whereas in the LA group SVR reduced at baseline and at the end of the procedure. Global cardiovascular performance was evaluated by looking at cardiac cycle efficiency and found improved performance in the DS group after anaesthesia and improved performance in the LA group after TAVI. The MAP-dicrotic pressure reduced in both groups but more significantly in the DS group. There were 32 cases of aortic regurgitation following TAVI with patients in the LA groups (23) being detected more easily given their stable haemodynamic status. [11]
Durand et al studied the outcomes of TAVI in 151 patients with the use of LA alone. They suggest due to reduction in femoral sheath sizes, advances with prosthetic valves and increased operators, what was once performed with GA can be done with LA. Lidocaine 2% (20 to 30 mls) was infiltrated to the skin overlying the femoral artery, additional small doses of midazolam and nalbuphine used for sedation if required. SAPIEN and SAPIEN XT valves were used with valve position for these cases were confirmed by using fluoroscopy. Mean LogEuroSCORE was 22.8% and mean age was 83.3+/-6.4. Insertion of the SAPIEN valve required a surgical arterial cut down approach and required the presence of a cardiac surgeon, the SAPIEN XT valve was percutaneous. Overall, the procedure was well tolerated with a 95.4% success rate. Procedural failure was related to unsuccessful vascular access (2%) or severe AR (2.6%). Conversion to GA occurred in 3.3% (only SAPIEN cases) with only one case needing conversion prior to the procedure due to annulus rupture. The majority were haemodynamically stable with only 5.5% requiring vasopressors. Endotracheal intubation was not required to improve patient’s compliance or comfort. [12]
Oguri et al performed an analysis of the FRANCE 2 registry which compared data from multiple centres and the clinical outcomes of those who had GA and LA for TAVI. 2326 patients of which 1377 had GA and 949 had LA with a mean age of 83.1+/-7.2 years were studied. High success rates were seen in both forms of anaesthesia: 97.6% in GA and 97% in LA. TOE as expected was used more often in the GA group. The Edwards valve was used more frequently with the GA group. Length of ICU and hospital stay was greater in the LA group. No differences were noted between groups in terms of complications such as stroke, myocardial infarction, or bleeding complications. Mild post procedural AR was not significantly different between groups, though the incidence was higher in the LA group. 15.1% of patients died during follow up with 53.1% of deaths within 30 days. 30-day mortality rates due to respiratory failure had a higher incidence in the GA group. No significant difference was noted between groups in 30 day or 1 year mortality. [13]
Table 3 consists of a summary of current literature on outcomes in TAVI related to anaesthetic choice.