Blood flow index as an indicator of successful sciatic nerve block: a prospective observational study using laser speckle contrast imaging

Wu, Xi; Li, J.; Joypaul, K.; Bao, Wei; Wang, D.; Huang, Yujie; Li, P.C.; Mei, Wei

doi:10.1016/j.bja.2018.05.065

Cited by 11 publications

(9 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These change rates of SWV N and SWV NMR showing higher diagnostic abilities may be attributed to further normalization of the differences in SWVs between individuals compared with the actual SWV N and SWV NMR values through ratio calculations before and after nerve block This speculation is strongly supported by the results that the CV values of the change rates of SWV N and SWV NMR were lower than those of the respective actual measurements. Similar to our results, the ndings of a previous study demonstrated that the relative change rate of the peripheral blood ow index from the baseline values has a higher diagnostic ability than actual values in determining the effect of the peripheral nerve block because of the large individual variation in baseline value 47 . Collectively, it is suggested that evaluating the ratio of SWV values of nerve to muscle and change rate in the SWV value, rather than measuring the actual SWV value itself, is an important factor for assessing nerve block success.…”

Section: Discussionsupporting

confidence: 91%

“…The discrepancy between these studies and our present results may be explained by differences in the measurement methods used. In previous studies, nerve blood ow was directly measured adjacent to the target nerve using a laser Doppler owmeter 47 , which theoretically has a higher detection sensitivity of blood ow compared to SMI. We speculate that the change in the nerve blood ow induced by the local anesthetic is very faint and lower than the detection sensitivity of SMI, and as a result, the SMI failed to identify this blood ow change in the present study.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Prediction of nerve block success using ultrasonographic parameters: A preliminary animal study

Chiba

Hamamoto

Kanai

et al. 2021

Preprint

View full text Add to dashboard Cite

This study aimed to evaluate the diagnostic value of ultrasonographic parameters as an indicator for predicting regional nerve block success. Ultrasound-guided sciatic nerve block was performed in seven dogs using either 2% mepivacaine (nerve-block group) or saline (sham-block group). The cross-sectional area (CSA), nerve blood flow (NBF), and shear wave velocity (SWV) of the sciatic nerve (SWVN), SWV of the biceps femoris muscle (SWVM), and their ratio (SWVNMR) were measured at 0, 30, 60, and 90 min after the nerve block as well as the change rate of each parameter from the baseline. A receiver operating characteristic (ROC) curve analysis was performed to determine the diagnostic value of each parameter in the prediction of nerve block success. No significant changes were observed in the CSA or NBF in association with the nerve block. The SWVN and SWVNMR in the nerve-block group were significantly higher than those in the sham-block group at 90 min and at 30, 60, and 90 min, respectively (p < 0.05). The change rates of SWVN and SWVNMR in the nerve-block group were significantly higher than those in the sham-block group at all time points (p < 0.05). The ROC curve analysis showed that SWVN had a moderate diagnostic accuracy (area under the curve [AUC], 0.779), whereas SWVNMR and change rates of SWVN and SWVNMR had a high diagnostic accuracy (AUC, 0.947, 0.998, and 1.000, respectively). Ultrasonographic evaluation of the SWVN and SWVNMR could be used as indicators for predicting nerve block success.

show abstract

Section: Discussionsupporting

confidence: 91%

Section: Discussionmentioning

confidence: 99%

Prediction of nerve block success using ultrasonographic parameters: A preliminary animal study

Chiba

Hamamoto

Kanai

et al. 2021

Preprint

View full text Add to dashboard Cite

show abstract

“…Due to our previous study, the LSCI technique could be employed to predict the effect of sciatic nerve block in clinical practice. 16 But the application of this technique in the upper limb needs to be confirmed since the composition and distribution of vascular nerves in upper or lower extremities differ. 14 The BFI value got the biggest rise after the C7 nerve root block in the innervated area (nail bed of the middle finger), which was similar to the one after C6 nerve root block in the innervated area (nail bed of the index finger).…”

Section: Discussionmentioning

confidence: 99%

<p>Blood Flow Index and Skin Temperature Measured by Laser Speckle Contrast Imaging and Infrared Thermography After Specific Ultrasound-Guided Blocking of the C6, C7 Nerve Root: A Case Report</p>

Zhang

Fan

Mei

2020

JPR

View full text Add to dashboard Cite

Ultrasound-guided cervical nerve root block is the technique of injecting local anesthetic or steroid into the intertubercular groove outside of the cervical foramen under real-time ultrasound guidance. It has established diagnostic and therapeutic employment for patients suffering symptoms caused by cervical disc disorders and foraminal stenosis. Measures of selective nerve root blockade would have vital clinical utility, especially in multilevel disease or combined with atypical symptoms, where subjective assessment is difficult. This case reported a 47-year-old male patient who suffered from severe radicular pain confined to the index and middle fingers, with weakness of the right upper extremity. He was successfully treated with selective C6, C7 nerve root under ultrasound guidance. For confirmation of the proper analgesia range, laser speckle contrast imaging (LSCI) and infrared thermography (IT) were both constructed over the dorsum of the hands and forearms during the procedure. The results of the off-line analysis suggested LSCI and IT might be considered as alternative measurements for the selective cervical nerve root.

show abstract

“…22 As we have previously reported, the BFI values of toes were significantly increased after successful sciatic nerve block. 20 Therefore, the nail bed of each toe was chosen as region of interests in this study.…”

Section: Discussionmentioning

confidence: 99%

“…[14][15][16][17][18][19] Our previous study demonstrated that LSCI might be an early, objective, quantitative, and reliable indicator of successful sciatic block. 20 The primary aim of this study was to investigate blood flow changes after lumbar plexus block using LSCI technique.…”

Section: Introductionmentioning

confidence: 99%

Predicting successful lumbar plexus block using blood flow index measured by laser speckle contrast imaging

Liu

et al. 2019

Preprint

View full text Add to dashboard Cite

Background: Laser speckle contrast imaging (LSCI) is a powerful optical imaging technique for real-time and dynamic measurement of regional blood flow. The objective of this prospective observational study was to investigate blood flow after changes blockade of lumbar plexus or its three major branches respectively, with LSCI technique.Methods: This study included 47 adult patients scheduled for elective lower limb surgery. For the selective blockade of lumbar plexus, femoral nerve, obturator nerve, and lateral femoral cutaneous nerve, blood flow images and pinprick sensory scores of the blocked lower limb were recorded 5 min pre block and every 5 min for 30 min post block. Blood flow index (BFI) values of toes were calculated by LSCI software.Results: In this study, we have 21 cases of successful lumbar plexus blocks, 2 cases of failed lumbar plexus block, 8 cases of successful femoral nerve blocks, 8 cases of successful obturator nerve blocks, and 8 cases of successful lateral femoral cutaneous nerve blocks. The BFI values of all five toes were significantly increased as early as 5 min after successful lumbar plexus block, whereas no signiﬁcant difference was found in BFI values after failed lumbar plexus block. BFI changes after successful selective blockade of femoral nerve, obturator nerve, or lateral femoral cutaneous nerve were negligible. BFI value of the big toe at 5 min after the successful lumbar plexus block was increased by 2.57 fold compared with the baseline value, which represented the highest increase among five tested toes. BFI value of the big toe at 10 min after lumbar plexus block showed great power to predict block outcome with a sensitivity of 100% and a speciﬁcity of 100%. The optimal cut-off value given by ROC analysis was 22.11 PU.Conclusions: Increased blood flow index measured by laser speckle contrast imaging is a reliable indicator of successful lumbar plexus block, but cannot indicate successful selective blocks of three major branches of the lumbar plexus. BFI value of the big toe at 10 min after lumbar plexus block could well predict block outcome with the cut-off value of 22.11 PU.Trial registration: NCT03169517 (Date of registration: May 25, 2017).

show abstract

Blood flow index as an indicator of successful sciatic nerve block: a prospective observational study using laser speckle contrast imaging

Abstract: NCT03169517.

Cited by 11 publications

References 32 publications

Prediction of nerve block success using ultrasonographic parameters: A preliminary animal study

Prediction of nerve block success using ultrasonographic parameters: A preliminary animal study

<p>Blood Flow Index and Skin Temperature Measured by Laser Speckle Contrast Imaging and Infrared Thermography After Specific Ultrasound-Guided Blocking of the C6, C7 Nerve Root: A Case Report</p>

Predicting successful lumbar plexus block using blood flow index measured by laser speckle contrast imaging

Contact Info

Product

Resources

About