This systematic review and meta-analysis included 1089 patients from 9 studies (7 RCTs and 2 retrospective studies). The aim was to compare the safety and efficacy of different means of anesthetic (LA versus RA) care. We retrieved data on primary patency rates, operation durations, brachial artery diameters, incidence of fistula thrombosis, BPBs until 6-weeks post-fistula creation, and pain intensity, and carried out between-group (LA versus RA) comparisons. Patients receiving RA were found to have significantly different primary patency rates, operation durations, and brachial artery diameters compared with patients receiving LA. No significant between-group differences were found regarding the incidence of fistula thrombosis, blocks until 6-weeks post-fistula creation, or pain intensity. Our meta-analysis provides class 1 evidence that RA is preferable to LA in patients with end-stage renal disease. Combined data from the current meta-analysis demonstrates that RA is associated with higher AVF primary patency rates and improved local blood flow compared with LA [11].
Axillary-approached BPB (RA) was preferable to LA. Arterial and venous dilation are crucial for AVF maturation [3] yet vascular surgery, such as local infiltration anesthesia, can easily lead to vessel spasm, impairing blood flow and potentially resulting in early fistula thrombosis. Comparatively, BPB can be performed using interscalene, supraclavicular, infraclavicular, and axillar approaches [5]. In a recent study, BPB was found to provide higher blood flow in the radial artery and AVF compared to infiltration anesthesia[12] given the sympatholytic effect, producing significant vasodilatation, decreased vascular resistance[13], and increased local blood flow. This is consistent with other recent studies, showing improvements in arterial blood flow and vasodilatation with RA. In a recent study by Nofal et al, the overall mean AVF blood flow was 42.21 ml/min more in the AxBP versus LA group. Similarly, a report by Malovrh [14] revealed a mean preoperative flow rate of 54.5 ml/min in BPB vessels with a successful outcome versus 24.1 ml/min in vessels that failed LA. In another study by Sahin et al [3], improved blood flow in the radial artery was significantly greater post- versus pre- anesthesia. Moreover, post-anesthesia and just pre-surgery, radial artery blood flow was 56 8.6 mL/min in the BPB group versus 40.7 6.1 mL/min in the LA group (P ༜ 0.001). Finally, Ebert et al [14] reported that both mean arterial and venous blood flow were increased (1.9 and 8.6 times, respectively) after BPB. Thus, we conclude that BPB anesthesia techniques in AVF construction can contribute to vessel dilation and reduced vasospasm via sympathectomy-like effects, increasing fistula blood flow, reducing fistula maturation time, and improving the success rates of vascular access procedures.
Arteriovenous fistulae operations can be performed under GA, LA, or RA. General anesthesia is associated with increased morbidity [16], such as through cardiorespiratory complications in patients with end-stage renal disease, whilst LA is associated with complications such as vasospasm and pain and discomfort during surgery [15, 17, 18]. By comparison, RA (e.g. BPB), which is a targeted injection of LA to specifically block the motor and sensory nerves that supply the operative site, is less complicated than GA and safer than LA. Moreover, BPB can be performed under ultrasound guidance, allowing for more accurate placement of the injection needle as well as more rapid onset and longer duration of the block, reduced vascular and neurological complications, and minimization of the volume of LA required [19, 20].
Pain control is also an important indicator of surgical success. Adequate pain control is extremely important in patients with end-stage renal disease with severe co-morbidities[21]. The prospective, randomized, clinical study from Shoshiashvili et al [6] showed significantly different results between BPB and LA groups in terms of pain intensity. The need for intra- as well as post- operative pain killers was significantly less in the BPB versus LA group (p = 0.0363 and p = 0.0318, respectively). Moreover, time to postoperative pain initiation was significantly higher in the RA versus LA group. Thus, we conclude that RA provides better pain control intra- as well as post- operatively in dialysis AVF operations, enabling patients to feel more comfortable [6].
The results of our study are consistent with those of previous meta-analyses. In a systematic review of 6 randomized trials (462 patients) and one retrospective study (408 patients), Ismail et al. [22] reported that RA improves the primary patency rate of AVF compared to LA.
Limitations
Our study has several limitations. First, BPB can be performed with interscalene, supraclavicular, infraclavicular and axillar approaches. We included studies using different approaches for BPB, and did not consider the effects of these approaches in our comparison of LA versus RA. Future studies are thus required to explore the effect of different anesthetic approaches on the outcomes of BPB. Second, three of the studies included in our study were single-center trials with an inherent risk of bias. Moreover, there are relatively few primary studies available in the literature. Both of these factors restrict the generalizability of our findings. Third, only short-term data are reported in the literature; thus, future studies are required to explore longer-term outcomes. Finally, only one study explored patients’ attitudes towards anesthesia and, thus, future trials are recommended to explore the differences between LA and RA in terms of patient-oriented outcomes.