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. 2022 Jul;66(7):511-516.
doi: 10.4103/ija.ija_405_22. Epub 2022 Jul 22.

Estimation of the minimum effective volume of 0.5% bupivacaine for ultrasound-guided popliteal sciatic nerve block in diabetic patients with neuropathy

Srinivasan Parthasarathy  1 , Avijit Chanda  1 , Balachandar Saravanan  2
Affiliations

Estimation of the minimum effective volume of 0.5% bupivacaine for ultrasound-guided popliteal sciatic nerve block in diabetic patients with neuropathy

Srinivasan Parthasarathy et al. Indian J Anaesth. 2022 Jul.

Abstract

Background and aims: The safety of conventional regional nerve block techniques in patients with established neuropathies, such as diabetic peripheral neuropathy (DPN), is still unclear. We designed this prospective dose finding study to identify the minimum effective local anaesthetic volume of 0.5% bupivacaine for ultrasound-guided subparaneural popliteal sciatic nerve block in 90% of DPN patients undergoing below-knee surgery (MELAV90).

Methods: Fifty-three patients with diabetic peripheral neuropathy and scheduled for below knee surgical procedure received popliteal sciatic nerve block under ultrasound guidance. The initial local anaesthetic volume used was 10 ml of 0.5% bupivacaine. The subsequent local anaesthetic volume allocation was based on biased-coin-design. Accordingly, the local anaesthetic volume given to each subject was based on the block outcome of the previous patient. The study included patients prospectively until 45 successful blocks were obtained. The primary measurement was the minimum effective local anaesthetic volume resulting in a successful subparaneural popliteal sciatic nerve block in 90% of DPN patients. The MELAV90 was calculated using isotonic regression and a 95% confidence interval bootstrapping method.

Results: The study included 53 patients to obtain 45 successful blocks. The MELAV90 of 0.5% bupivacaine was obtained at 5.85 ml (95% confidence interval, 5.72 to 6.22 ml). Eight patients needed supplemental anaesthesia to complete the surgery. No other complications were noted.

Conclusion: For patients with diabetic peripheral neuropathy undergoing below-knee surgery, the MELAV90 of 0.5% bupivacaine for subparaneural popliteal sciatic nerve to achieve surgical anaesthesia was 5.85 ml.

Keywords: Bupivacaine; diabetic neuropathy; minimum effective anaesthetic volume; nerve block; popliteal-sciatic nerve; ultrasound.

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Conflict of interest statement

There are no conflicts of interest.

Figures

Figure 1
Figure 1
Showing popliteal sciatic nerve block ergonomics. (a) Patient in the prone position, (b) Ultrasound image screen in front of the performer
Figure 2
Figure 2
(a) Showing ultrasound image of the popliteal sciatic nerve at the level of nerve bifurcation (Bi-lobular pattern), (b) Arrow indicates the circumferential spread of local anaesthetic around the nerve. TN – Tibial nerve; CPN – Common peroneal nerve; PA – Popliteal artery; PV – Popliteal vein
Figure 3
Figure 3
The up and down sequence shows the study participant’s response to the different volumes of 0.5% bupivacaine
See this image and copyright information in PMC

References

    1. Hicks CW, Selvin E. Epidemiology of peripheral neuropathy and lower extremity disease in diabetes. Curr Diab Rep. 2019;19:86. - PMC - PubMed
    1. Boulton AJM. Diabetic neuropathy and foot complications. Zochodne DW, Malik RA, editors. Diabetes and the Nervous System. Elsevier. 2014:97–107. - PubMed
    1. Arjun BK, Prijith RS, Sreeraghu GM, Narendrababu MC. Ultrasound-guided popliteal sciatic and adductor canal block for below-knee surgeries in high-risk patients. Indian J Anaesth. 2019;63:635–9. - PMC - PubMed
    1. Baeriswyl M, Taffé P, Kirkham KR, Bathory I, Rancati V, Crevoisier X, et al. Comparison of peripheral nerve blockade characteristics between non-diabetic patients and patients suffering from diabetic neuropathy:A prospective cohort study. Anaesthesia. 2018;73:1110–7. - PubMed
    1. Lirk P, Verhamme C, Boeckh R, Stevens MF, ten Hoope W, Gerner P, et al. Effects of early and late diabetic neuropathy on sciatic nerve block duration and neurotoxicity in Zucker diabetic fatty rats. Br J Anaesth. 2015;114:319–26. - PubMed