Comparison of peripheral nerve blockade characteristics between non-diabetic patients and patients suffering from diabetic neuropathy: a prospective cohort study

Foot Drop Following a Popliteal Sciatic Nerve Block with Ropivacaine, A Case Report and Literature Review

Although peripheral nerve blocks are deemed very safe, a significant number of patients for whom this anesthetic technique may be particularly appealing to apply may present with preexisting peripheral neuropathies, putting them at risk for further nerve damage. We present a case with a 74-year-old male with several risk factors for peripheral neuropathy who developed a foot drop following a popliteal sciatic nerve block with ropivacaine. We suggest that the vasoconstrictive properties of ropivacaine may have contributed to a preexisting neuronal ischemia, thus further damaging an already compromised nerve.

Do you mind the role of spinal sensory block duration in a crucial endocrine disorder of diabetes mellitus? A prospective observational study

OBJECTIVE

Diabetes mellitus, per se, is a global health concern, which is often accompanied by complications such as diabetic neuropathy. This prospective observational study purposed to assess the durations of spinal sensory block and motor blocks in individuals with and without diabetes mellitus who had undergone spinal anesthesia.

METHODS

This study incorporated 80 cases, which were evenly divided into spinal sensory block without diabetes mellitus and spinal sensory block with diabetes mellitus. Various parameters were recorded at different time points, including heart rate, mean arterial blood pressure, SpO2, and spinal block characteristics. Notable measures included maximum spinal sensory block onset time, time to reach the 10th thoracic vertebra (T10), maximal spinal sensory block, time for Bromage scores, and block regression while controlling for age-related variations.

RESULTS

Patients in the diabetic group exhibited extended block durations, with significant differences in heart rate noted at specific time points. Regarding the spinal block characteristics, the "maximum onset of SSB" and the "time to reach the T10" were more prolonged in the SSBwDM without significance. Maximum sensory spinal sensory block did not differ. However, some cases in the SSBwDM displayed blocks extending up to the T6. The times to achieve Bromage motor block scores 1-3 were shorter in SSBwDM and lost significance regarding age. Notably, the regression time was longer in SSBwDM, which held significance for both parameters.

CONCLUSION

Diabetic cases commonly encounter prolonged block durations post-subarachnoid intervention, potentially linked to nerve sensitivity, age-related changes, and glycemic control. As such, attenuated local doses for diabetic neuropathic cases may enhance early mobilization, attenuate thromboembolic events, and expedite gastrointestinal recovery.

Diabetic Neuropathy and Minimum Effective Anesthetic Concentration of Mepivacaine for Axillary Brachial Plexus Block: A Prospective Observational Study

Nerves in patients with diabetic neuropathy (DN) show increased susceptibility to local anesthetics, potentially requiring a decreased dose. We investigated whether the minimum effective anesthetic concentration (MEAC) of mepivacaine for successful axillary block is lower in patients with DN than in those without. This prospective observational study included patients with DN (n = 22) and without diabetes (n = 22) at a tertiary care center. Patients received an ultrasound-guided axillary block with 30 mL of mepivacaine for anesthesia. The mepivacaine concentration used in each patient was calculated using Dixon's up-and-down method. A block was considered successful if all four sensory nerves had a score of 1 or 2 within 30 min with no pain during surgery. The primary outcome was the MEAC of mepivacaine, and the secondary outcomes included the minimal nerve stimulation intensity for the musculocutaneous nerve and the occurrence of adverse events. The MEAC50 was 0.55% (95% CI 0.33-0.77%) in patients without diabetes and 0.58% (95% CI 0.39-0.77%) in patients with DN (p = 0.837). The MEAC90 was 0.98% (95% CI 0.54-1.42%) in patients without diabetes and 0.96% (95% CI 0.57-1.35%) in patients with DN (p = 0.949). The stimulation threshold for the musculocutaneous nerve was significantly different between groups (0.49 mA vs. 0.19 mA for patients with vs. without diabetes; p = 0.002). In conclusion, the MEAC of mepivacaine for a successful axillary block is not lower in patients with DN.

Duration of analgesia after forefoot surgery compared between an ankle and a sciatic nerve block at the popliteal crease: A randomised controlled single-blinded trial

BACKGROUND

Forefoot surgery is associated with severe postoperative pain. Ankle and sciatic nerve blocks provide satisfactory postoperative analgesia after forefoot surgery, but little is known on their respective duration of analgesia.

OBJECTIVE

This randomised controlled, single-blinded trial tested the hypothesis that after forefoot surgery in the setting of multimodal analgesia, an ankle block provides analgesia superior to that of a sciatic nerve block at the popliteal crease.

DESIGN

A randomised controlled study.

SETTING

A single centre study in a university hospital in Switzerland, from September 2018 to November 2022.

PATIENTS

From 91 patients scheduled for forefoot surgery, 60 met the inclusion criteria of which 56 completed the protocol and their data were available for analysis. Exclusion criteria were existing sciatic nerve deficit, pre-existing peripheral neuropathy, chronic pain diagnosis, pregnancy, or identified contraindications to peripheral nerve block.

INTERVENTION

Patients undergoing forefoot surgery were randomly allocated to either a multi-injection ankle block (partly under ultrasound guidance) or a sciatic nerve block at the popliteal crease (under ultrasound guidance) combined with a saphenous nerve block at the ankle. Patients in each group received a total of 30 ml of ropivacaine 0.5% and a multimodal analgesic regimen inclusive of dexamethasone, paracetamol, ketorolac then ibuprofen.

MAIN OUTCOME MEASURE

The primary outcome was duration of analgesia, defined as time to first morphine request.

RESULTS

Mean ± SD duration of analgesia was 15.4 ± 8.0 h in the ankle block group and 20.0 ± 10.3 h in the sciatic nerve block group ( P  = 0.32). Of note, 15 of 26 (58%) and 24 of 30 (80%) patients of the ankle and sciatic nerve block groups did not request any morphine ( P  = 0.09). Other secondary outcomes were similar between groups.

CONCLUSION

Compared with the ankle block, the sciatic nerve block at the popliteal crease does not provide a longer duration of analgesia in patients undergoing forefoot surgery in the setting of multimodal analgesia.

TRIAL REGISTRATION

Clinicaltrials.com identifier: NCT03683342.

Endovascular revascularization of critical limb ischemia: the role of ultrasound-guided popliteal sciatic nerve block for the procedural pain management

OBJECTIVES

To evaluate the impact of the ultrasound-guided popliteal sciatic nerve block (PSNB) for pain management during endovascular treatment of chronic limb-threatening ischemia (CLTI).

MATERIAL AND METHODS

From November 2020 to January 2022, 111 CLTI patients that underwent endovascular procedures were prospectively enrolled in this prospective single-arm interventional study. Ultrasound-guided PSNB was used for procedural pain control. Pain intensity was evaluated throughout the procedure (baseline, 10 min after the block, pain peak, and at the end of the procedure) with the visual analog scale (VAS).

RESULTS

Forty-six patients underwent above-the-knee revascularization (ATK), 20/111 below-the-knee (BTK) revascularization, 20/111 to both ATK and BTK revascularization. In 25 cases, no endovascular option was feasible at diagnostic angiography. The PSNB was effective in 96% of patients, with no need for further pain management with a statistically significant reduction (p < 0.0001) in the mean value of the VAS from 7.86 ± 1.81 (pre-procedural) to 2.04 ± 2.20 after 10 min from the block and up to 0.74 ± 1.43 at the end of the procedure (mean time 43 min). Only 1 complication related to the popliteal sciatic nerve block was registered (a temporary foot drop, completely resolved within 48 h). The time necessary to perform the block ranged between 4 and 10 min.

CONCLUSION

Ultrasound-guided PSNB is a feasible and effective method to manage patients with rest pain and increase comfort and compliance during endovascular procedures.

CLINICAL RELEVANCE STATEMENT

An ultrasound-guided popliteal sciatic nerve block is a safe, feasible, and effective technique to manage pain during endovascular treatment of chronic limb-threatening ischemia, especially in frail patients with multiple comorbidities who are poor candidates for deep sedoanalgesia or general anesthesia.

KEY POINTS

Endovascular treatment of CTLI may require long revascularization sessions in patients with high levels of pain at rest, which could be exacerbated during the revascularization procedure. The PSNB is routinely used for anesthesia and analgesia during foot and ankle surgery, but the experience with lower limb revascularization procedures is very limited and not included in any international guideline. Ultrasound-guided PSNB is a feasible and effective regional anesthesia technique to relieve procedural and resting pain. Because of its safety and availability, every interventional radiologist should know how to perform this type of loco-regional anesthesia.

Necrotizing Fasciitis and Diabetic Foot: Results of a Prompt Identification, Surgery and Antibiotic Therapy (P.I.S.A.) Protocol

Necrotizing fasciitis (NF) is a rapidly progressive, life-threatening infection, involving the skin, soft tissue and fascia. We evaluated outcomes of its surgical management in diabetic foot (DF) patients in a tertiary referral centre. We retrospectively searched for NF in the database of our DF Section from 2016 to 2018. All cases were treated according to a multiprofessional integrated protocol, with Prompt Identification, Surgical debridement and systemic Antibiotic therapy (P.I.S.A. Protocol). We analysed short-term evolution (surgical procedures and major amputations), and long-term outcomes (survival and healing rates). Sixty-eight patients were referred to our DF clinic for suspicion of NF. The diagnosis was confirmed in 54 (79.4%; male/female 40/14; type 1/2 diabetes 6/48; age 62.8 ± 8.1 years; duration of diabetes 13.6 ± 10.1 years). According to the microbiological results, cases were classified as Type 1 (33-61.2%), 2 (7-12.9%) and 3 (14-25.9%). No significant differences were observed. All patients underwent a decompressive fasciotomy. Six patients (11.1%) required also a forefoot amputation and 12 (22.2%) a toe or ray amputation. No major amputation was performed in the short-term period. During the follow-up (26 ± 12 months) 46 patients (85%) healed in 94 ± 11 days. Of the remaining 8: 5 (9.2%) died for other reasons before healing, 2 (3.7%) recurred and one (1.9%) required a major amputation. Our experience reveals a relatively high prevalence of NF in DF; despite this, we observed how, when promptly and aggressively treated, NF has a good prognosis and it is not associated with an excess of limb loss and deaths.

Prolonged duration of epidural labour analgesia decreases the success rate of epidural anaesthesia for caesarean section

OBJECTIVE

To summarise the process of conversion of epidural labour analgesia to anaesthesia for caesarean delivery and explore the relationship between duration of labour analgesia and conversion.

METHODS

Parturients who underwent conversion from epidural labour analgesia to anaesthesia for caesarean delivery between May 2019 and April 2020 at the Chengdu Women's and Children's Central Hospital, Sichuan Maternal and Child Health Hospital, and Jinjiang District Maternal and Child Health Hospital were selected. If the position of the epidural catheter was correct and the effect was good, patients were converted to epidural surgical anaesthesia. If epidural labour analgesia was ineffective, spinal anaesthesia (SA) was administered immediately. For category-1 emergency caesarean sections, general anaesthesia (GA) was administered.

RESULTS

A total of 1084 parturients underwent conversion. Of these, 19 (1.9%) received GA due to the initiation of category-1 emergency caesarean section. 704 (64.9%) were converted to epidural surgical anaesthesia, 2 (0.2%) had failed conversions and were administered GA before delivery, and 357 (32.9%) were converted to SA. Logistic regression analysis showed that prolonged duration of epidural labour analgesia ([Crude odds ratio (OR)=1.065; 95% confidence interval (CI), 1.037-1.094; p < .01]; [Adjusted OR = 1.060; 95% CI, 1.031-1.091; p < .01]) was an independent risk factor for conversion failure. A receiver operating characteristic curve constructed using duration of epidural labour analgesia showed that parturients with a duration of epidural labour analgesia ≥8 h, more frequently required a change of anaesthesia technique during conversion, and the relative risk of conversion failure was 1.54 (95% CI, 1.23-1.93; p < .01).

CONCLUSION

Prolonged duration of epidural labour analgesia increases the possibility of having an invalid epidural catheter, resulting in an increased risk of conversion failure from epidural labour analgesia to epidural surgical anaesthesia. Further, this risk is higher when the time exceeds 8 h. KEY MESSAGESProlonged duration of epidural labour analgesia > 8 h is associated with conversion failure.If it is impossible to judge whether the conversion is successful immediately, spinal anaesthesia should be administered to minimise complications.

The Influence of Diabetic Peripheral Neuropathy on the Duration of Sciatic Nerve Block with 1.3% Liposomal Bupivacaine and 0.25% Bupivacaine Hydrochloride in a Mouse Model

Little is known regarding the pharmacological properties of extended-release local anesthetics in the setting of diabetic peripheral neuropathy. We investigated and compared the duration of sciatic nerve block following administration of clinically relevant concentrations of liposomal bupivacaine (LB) and bupivacaine hydrochloride (BH) in diabetic mice with peripheral neuropathy. In this prospective, randomized, and double-blind study, twenty-four female C57BL/6J-OlaHsd mice were assigned to a streptozotocin-induced type 1 diabetes group and a control group without diabetes. The presence of peripheral neuropathy was established by assessing the duration of thermal latency of the plantar and tail-flick tests, following which both groups were subdivided into two subgroups in which 35 mg/kg of 1.31% LB and 7 mg/kg of 0.25% BH were respectively administered for sciatic nerve block. The average sensory block duration with BH was 106 min and 117.1 min in the control and diabetic groups, respectively. With LB, the average sensory block duration was 118 min in the control mice, while in mice with diabetic peripheral neuropathy, the average block duration was significantly longer and above the 270 min limit set in our study. Accordingly, sensory block duration was longer with LB compared to BH, and diabetic peripheral neuropathy significantly increased sciatic nerve block duration with LB.

Preoperative Factors Associated with Anesthesia Failure for Patients Undergoing Nonsurgical Root Canal Therapy: A National Dental Practice-Based Research Network Study

INTRODUCTION

The aim of this study was to identify preoperative factors associated with local anesthesia failure.

METHODS

The National Dental Practice-Based Research Network (www.NationalDentalPBRN.org) data from 534 patients who received a nonsurgical root canal treatment completed in a single appointment were included in this analysis. Three methods for defining anesthesia failure were used: definition 1, patient-reported level of numbness; definition 2, provider-reported quality of anesthesia; and definition 3, provider-reported use of supplemental anesthesia. Fifty-one preoperative factors were investigated and analyzed individually against the overall failure rate for each method, and multivariate generalized estimating equation logistic models were fit with predictors chosen using stepwise model selection to evaluate factors that may interact with each other.

RESULTS

The overall anesthesia failure rates were 5%, 15%, and 30% for definitions 1, 2, and 3, respectively. Provider experience, diabetes, absence of sharp or aching pain, absence of smoking, and a fair expected outcome were associated with anesthesia failure (definition 1). Provider level of training, absence of a sinus tract, bite sensitivity, and stress making the pain worse were associated with anesthesia failure (definition 2). Provider level of training, pain provoked by stimulus, mandibular teeth, teeth with vital pulps, and pain interfering with daily activities were associated with the use of supplemental anesthesia (definition 3).

CONCLUSIONS

With the range of 5%-30% of anesthesia failures, a few common factors across the models assessed were elucidated. Providers with higher levels of training had significantly fewer anesthesia failures. Patient self-reported history of diabetes and preoperative pain-related interference with daily activities were associated with more anesthesia failures. Greater severity of various tooth-related pain characteristics, as a group but not individually, accounted for more anesthesia failures.

Ultrasound-guided peripheral trunk block technique: A new approach gradually stepping onto the stage of clinical anesthesia

In recent years, with the continuous development and validation of new visualization, the ultrasound-guided peripheral trunk block becomes more mature and has a more extensive and broader implementation scope in clinical anesthesia. Based on this, we reviewed and summarized the literature on peripheral trunk nerve block include: paraspinal block, retrolaminar block, plane block of erect spinal muscle, transverse convex to pleural midpoint block, block of the trapezius muscle and anterior serratus muscle, anterior serratus muscle block, thoracic nerve block, abdominal transverse fascia block, type-I block of quadratus lumborum, type-II block of quadratus lumborum, type-III block of quadratus lumborum, block of the sheath of rectus abdominis. This paper reviews the ultrasound-guided peripheral trunk block technique, including development history, anatomic basis, implementation methods, advantages and disadvantages of nerve block technique, and describes the bottleneck and difficulties of nerve block technique at present.

Levobupivacaine Consumption in Automated Intermittent Bolus in Ultrasound Guided Subparaneural Sciatic Nerve Catheters: A Prospective Double-Blind Randomized Trial

Purpose

Continuous sciatic nerve blocks have proven benefits for postoperative analgesia after foot surgery. However, the optimal mode of administration remains a point of debate. Ultrasound guided subparaneural injection accelerates onset time and increases duration after a single shot sciatic nerve block. This double blind prospective randomized trial compares the 48-hour local anesthetic (LA) dose consumption of an automated intermittent bolus technique to a continuous infusion regimen in a subparaneural sciatic nerve catheter after hallux valgus surgery.

Patients and Methods

Patients scheduled for hallux valgus surgery were randomized to receive either a continuous infusion of levobupivacaine 0.125% at 5mL/h (group A) or an intermittent automated bolus of 9.8 mL every 2 hours with a background of 0.1 mL/h (group B), both with a PCA bolus of 6 mL and lockout of 30 minutes. The 48 hour LA consumption, PCA boluses, Numeric Rating Scale (NRS), satisfaction and return of normal sensation were recorded.

Results

Sixteen patients were excluded because of protocol violation or technical problems and 42 patients remained for analysis. The 48 hour ropivacaine consumption was higher in group A (293 ±60 mL) than group B (257±33 mL). The median and highest NRS scores and patient satisfaction were not statistically different between groups. Normal sensation returned after 75 ± 22 hours (group A) and 70 ± 17 hours (group B).

Conclusion

Programmed bolus administration in subparaneural sciatic nerve catheters reduces LA consumption 48 hours after surgery with equal analgesia and patient satisfaction. Return of sensation is variable and can last more than 75 hours.

Regional anaesthesia in patients with diabetes

Diabetes is the most common metabolic condition worldwide and about 20% of surgical patients will have this condition. It is a major risk-factor for worse outcomes after surgery including mortality; infective and non-infective complications; and increased length of stay. However, diabetes is a modifiable risk-factor, and programs to improve medical management have the potential to reduce peri-operative complications and the risk of harm. Regional anaesthesia has well-documented benefits in promoting the restoration of function but there are legitimate concerns that the incidence of complications of regional anaesthesia in patients with diabetes is higher. The aim of this review is to explore in detail the various potential advantages and disadvantages of regional anaesthesia in patients with diabetes. This, in turn, will allow practitioners to undertake more informed shared decision-making and potentially modify their anaesthetic technique for patients with diabetes.

Advances in regional anaesthesia and acute pain management: a narrative review

Regional anaesthesia has undergone several exciting advances in the past few decades. Ultrasound-guided techniques of peripheral nerve blockade have become the gold standard thanks to the associated improvements in efficacy, ease of performance and safety. This has increased the accessibility and utilisation of regional anaesthesia in the anaesthesia community at large and is timely given the mounting evidence for its potential benefits on various patient-centred outcomes, including major morbidity, cancer recurrence and persistent postoperative pain. Ultrasound guidance has also paved the way for refinement of the technical performance of existing blocks concerning simplicity and safety, as well as the development of new regional anaesthesia techniques. In particular, the emergence of fascial plane blocks has further broadened the application of regional anaesthesia in the management of painful conditions of the thorax and abdomen. The preliminary results of investigations into these fascial plane blocks are promising but require further research to establish their true value and role in clinical care. One of the challenges that remains is how best to prolong regional anaesthesia to maximise its benefits while avoiding undue harm. There is ongoing research into optimising continuous catheter techniques and their management, intravenous and perineural pharmacological adjuncts, and sustained-release local anaesthetic molecules. Finally, there is a growing appreciation for the critical role that regional anaesthesia can play in an overall multimodal anaesthetic strategy. This is especially pertinent given the current focus on eliminating unnecessary peri-operative opioid administration.

Sex-dependent prolongation of sciatic nerve blockade in diabetes patients: a prospective cohort study

INTRODUCTION

Diabetes may affect the duration of nerve block after regional anesthesia. This study aimed to compare the durations of sensory and motor block in diabetes versus non-diabetes patients after lower limb nerve block and delineate any sex-based differences in the duration of sensory and motor blocks of both diabetes and non-diabetes patients.

METHODS

This prospective single-blinded cohort study recruited 86 patients who underwent unilateral lower extremity surgery; 52 patients were non-diabetic and 34 were diabetic. Each patient received an ultrasound-guided nerve stimulator-assisted subgluteal sciatic nerve block with 0.75% ropivacaine. Duration of sensory block was assessed with the Semmes-Weinstein monofilament test, and duration of motor block was assessed with dorsal and plantar flexion of the foot.

RESULTS

The sensory and motor block durations of diabetes patients were significantly prolonged versus non-diabetes patients (19.8±6.0 hours vs 15.6±5.1 hours; p<0.05) and (19.5±8.1 hours vs 14.8±5.7 hours, p=0.005), respectively. The durations of sensory and motor block were comparable between male diabetes and non-diabetes patients, but they were significantly longer in female diabetes patients. Multiple regression analysis further revealed that, after adjustment for age and preoperative sensory threshold, diabetes, fasting plasma glucose and HbA1c levels were significantly associated with sensory and motor blocks. Sex analysis showed the association was only present in female diabetes patients, not male diabetes patients.

CONCLUSION

The durations of sensory and motor block are significantly prolonged after subgluteal sciatic nerve block in diabetes patients. Furthermore, the prolonged nerve blockade is present only in diabetes women, not diabetes men.

TRIAL REGISTRATION NUMBER

NCT02482831.