Bilateral ultrasound-guided maxillary and mandibular combined nerves block reduces morphine consumption after double-jaw orthognathic surgery: a randomized controlled trial

BACKGROUND

Double-jaw surgeries are known to be painful and to require opioids. Maxillary (V2) and mandibular (V3) nerves block could provide adequate pain management with minimal opioid-related side effects. Our main objective was to evaluate the analgesic effect of bilateral ultrasound-guided V2 and V3 combined nerves block in patients undergoing double-jaw orthognathic surgery.

METHODS

In this single-blind, randomized control study, 50 patients were prospectively allocated to either bilateral ultrasound-guided V2 and V3 combined nerves block or intraoral infiltration of local anesthetic. Primary outcome was the cumulative oral morphine equivalent (OME) consumption assessed at postoperative day 1. Secondary outcomes were cumulative OME consumption and pain scores in recovery room and at postoperative day 2, intraoperative anesthetic consumption, and opioid-related side effects. Preoperative anxiety was investigated by the Amsterdam Preoperative Anxiety and Information Scale (APAIS).

RESULTS

Compared with infiltration, ultrasound-guided regional anesthesia reduced cumulative OME consumption on day 1 (45.7±37.6 mg vs 25.5±19.8 mg, respectively, mean difference of -20.1 (95% CI -37.4 to -2.9) mg, p=0.023) and day 2 (64.5±60 mg vs 35.8±30.2 mg, respectively, mean difference of -28.7 (95% CI -55.9 to -1.43) mg, p=0.040). Interestingly, worst pain score and cumulative OME consumptions on day 2 were positively correlated with the APAIS (Pearson's correlation coefficient of 0.42 (p=0.003) and 0.39 (p=0.006), respectively).

CONCLUSION

Bilateral ultrasound-guided V2 and V3 combined nerves block reduces postoperative opioid consumption by about 50% in patients undergoing double-jaw surgery.

TRIAL REGISTRATION NUMBER

NCT05351151.

Multisite prospective study of perioperative pain management practices for anterior cruciate ligament reconstruction in adolescents: Society for Pediatric Anesthesia Improvement Network (SPAIN) Project Report

INTRODUCTION

Although 200 000 adolescents undergo anterior cruciate ligament reconstruction (ACLR) surgery annually, no benchmarks for pediatric post-ACLR pain management exist. We created a multicenter, prospective, observational registry to describe pain practices, pain, and functional recovery after pediatric ACLR.

METHODS

Participants (n=519; 12-17.5 years) were enrolled from 15 sites over 2 years. Data on perioperative management and surgical factors were collected. Pain/opioid use and Lysholm scores were assessed preoperatively, on postoperative day 1 (POD1), POD3, week 6, and month 6. Descriptive statistics and trends for opioid use, pain, and function are presented.

RESULTS

Regional analgesia was performed in 447/519 (86%) subjects; of these, adductor canal single shot was most frequent (54%), nerve catheters placed in 24%, and perineural adjuvants used in 43%. On POD1, POD3, week 6, and month 6, survey response rates were 73%, 71%, 61%, and 45%, respectively. Over these respective time points, pain score >3/10 was reported by 64% (95% CI: 59% to 69%), 46% (95% CI: 41% to 52%), 5% (95% CI: 3% to 8%), and 3% (95% CI: 1% to 6%); the number of daily oxycodone doses used was 2.8 (SD 0.19), 1.8 (SD 0.13), 0, and 0. There was considerable variability in timing and tests for postdischarge functional assessments. Numbness and weakness were reported by 11% and 4% at week 6 (n=315) and 16% and 2% at month 6 (n=233), respectively.

CONCLUSION

We found substantial variability in the use of blocks to manage post-ACLR pain in children, with a small percentage experiencing long-term pain and neurological symptoms. Studies are needed to determine best practices for regional anesthesia and functional assessments in this patient population.

Incomplete sensorimotor paresis after upper abdominal surgery with TEA and spinal epidural lipomatosis: a case report

INTRODUCTION

This case report documents a postoperative, incomplete sensorimotor paraparesis from thoracic vertebral body 6 (Th6) after combined anesthesia for upper abdominal surgery in a patient who had a thoracic localization of spinal epidural lipomatosis (SEL).

CASE PRESENTATION

The patient was treated in our clinic with a thoracic epidural catheter (TEA) for perioperative analgesia during a partial duodenopancreatectomy. Paraparetic symptoms occurred 20 hours after surgery. Initial MRI did not show bleeding, infection or spinal cord damage and the neurosurgeon consultants recommended observation. The neurological examination and the third follow-up MRI on 15th postoperative day showed ventrolateral damage of the spinal cord at level Th6. It is possible that local anesthetic compressed the spinal cord in addition to the existing lipomatosis and the thoracic kyphosis. The paraparesis improved during follow-up paraplegiologic treatment.

CONCLUSION

So far, only two uncomplicated lumbar epidural catheter anesthesias have been described in patients who had a lumbar SEL. Epidural catheter anesthesia is a safe and effective method of pain control. But it is important to carefully identify and stratify patients with risk factors during the premedication visit. In patients who had kyphosis and thoracic localization of SEL, TEA may only be used after a risk-benefit assessment.

Transitioning from intrathecal bupivacaine to mepivacaine for same-day discharge total joint arthroplasty: a quality improvement study

INTRODUCTION

Same-day discharge total knee and hip arthroplasty is becoming more common. Anesthetic approaches that optimize readiness for discharge are important. Based on an institutional change from low-dose bupivacaine to mepivacaine, we aimed to assess the impact on postanesthesia care unit (PACU) recovery in a quaternary care, academic medical center.

METHODS

In this quality improvement retrospective study, a single surgeon performed 96 combined total knee and hip arthroplasties booked as same-day discharge from September 20, 2021 to December 20, 2021. Starting on November 15, 2021 the subarachnoid block was performed with isobaric mepivacaine 37.5-45 mg instead of hyperbaric bupivacaine 9-10.5 mg. We compare these cohorts for time to discharge from PACU, perioperative oral morphine milligram equivalent (OMME) administration, PACU pain scores, conversion to general anesthesia (GA), and overnight admission.

RESULTS

We found the use of isobaric mepivacaine as compared with hyperbaric bupivacaine for intrathecal block in same-day discharge total joint arthroplasty was associated with decreased length of PACU stay at our academic center (median 4.03 vs 5.33 hours; p=0.008), increased perioperative OMME (mean 22.5 vs 11.4 mg; p<0.001), increased PACU pain scores (mean 6.29 vs 3.41; p<0.01) and no difference in conversion to GA or overnight admission.

CONCLUSIONS

Intrathecal mepivacaine was associated with increased perioperative OMME consumption and PACU pain scores, but still realized a decreased PACU length of stay.

Prediction of successful revision surgery for mesh-related complaints after inguinal hernia and pelvic organ prolapse repair

PURPOSE

With this retrospective case series, we aim to identify predictors for reduction of pain after mesh revision surgery in patients operated for inguinal hernia or pelvic organ prolapse with a polypropylene implant. Identifying these predictors may aid surgeons to counsel patients and select appropriate candidates for mesh revision surgery.

METHODS

Clinical records before and after mesh revision surgery from 221 patients with chronic postoperative inguinal pain (CPIP) and 59 patients with pain after pelvic organ prolapse (POP) surgery were collected at two experienced tertiary referral centers. Primary outcome was patient reported improvement of pain after revision surgery. A multivariable logistic regression model was used to specify predictors for pain reduction.

RESULTS

The multivariable logistic regression was performed for each patient group separately. Patients with CPIP had higher chances of improvement of pain when time between mesh placement and mesh revision surgery was longer, with an OR of 1.19 per year. A turning point in chances of risks and benefits was demonstrated at 70 months, with improved outcomes for patients with revision surgery ≥ 70 months (OR 2.86). For POP patients, no statistically significant predictors for reduction of pain after (partial) removal surgery could be identified.

CONCLUSION

A longer duration of at least 70 months between implantation of inguinal mesh and revision surgery seems to give a higher chance on improvement of pain. Caregivers should not avoid surgery based on a longer duration of symptoms when an association between symptoms and the location of the mesh is found.

Adductor canal block techniques do not lead to involvement of sciatic nerve branches: a radiological cadaveric study

INTRODUCTION

Low and high volume mid-thigh (ie, distal femoral triangle) and distal adductor canal block approaches are frequently applied for knee surgical procedures. Although these techniques aim to contain the injectate within the adductor canal, spillage into the popliteal fossa has been reported. While in theory this could improve analgesia, it might also result in motor blockade due to coverage of motor branches of the sciatic nerve. This radiological cadaveric study, therefore, investigated the incidence of coverage of sciatic nerve divisions after various adductor canal block techniques.

METHODS

Eighteen fresh, unfrozen and unembalmed human cadavers were randomized to receive ultrasound-guided distal femoral triangle or distal adductor canal injections, with 2 mL or 30 mL injectate volume, on both sides (36 blocks in total). The injectate was a 1:10 dilution of contrast medium in local anesthetic. Injectate spread was assessed using whole-body CT with reconstructions in axial, sagittal and coronal planes.

RESULTS

No coverage of the sciatic nerve or its main divisions was found. The contrast mixture spread to the popliteal fossa in three of 36 nerve blocks. Contrast reached the saphenous nerve after all injections, whereas the femoral nerve was always spared.

CONCLUSIONS

Adductor canal block techniques are unlikely, even when using larger volumes, to block the sciatic nerve, or its main branches. Furthermore, injectate reached the popliteal fossa in a small minority of cases, yet if a clinical analgesic effect is achieved by this mechanism is still unknown.

Dorsal root ganglion: a key to understanding the therapeutic effects of the erector spinae plane (ESP) and other intertransverse process blocks?

Since its description in 2016, the erector spinae plane block (ESPB) has become a widely employed regional anesthetic technique and kindled interest in a range of related techniques, collectively termed intertransverse process blocks. There has been ongoing controversy over mechanism of action of the ESPB, mainly due to incongruities between results of cutaneous sensory testing, clinical efficacy studies, and investigations into the neural structures that are reached by injected local anesthetic (LA). This paper reviews the spread of LA to the paravertebral and epidural space and the cutaneous anesthesia in ESPB, with specific emphasis on the dorsal root ganglion (DRG). We hypothesize that the DRG, due to its unique and complex microarchitecture, represents a key therapeutic target for modulation of nociceptive signaling in regional anesthesia. This paper discusses how the anatomical and physiological characteristics of the DRG may be one of the factors underpinning the clinical analgesia observed in ESPB and other intertransverse process blocks.

Local anesthetic dosing and toxicity of adult truncal catheters: a narrative review of published practice

BACKGROUND/IMPORTANCE

Anesthesiologists frequently use truncal catheters for postoperative pain control but with limited characterization of dosing and toxicity.

OBJECTIVE

We reviewed the published literature to characterize local anesthetic dosing and toxicity of paravertebral and transversus abdominis plane catheters in adults.

EVIDENCE REVIEW

We searched the literature for bupivacaine or ropivacaine infusions in the paravertebral or transversus abdominis space in humans dosed for 24 hours. We evaluated bolus dosing, infusion dosing and cumulative 24-hour dosing in adults. We also identified cases of local anesthetic systemic toxicity and toxic blood levels.

FINDINGS

Following screening, we extracted data from 121 and 108 papers for ropivacaine and bupivacaine respectively with a total of 6802 patients. For ropivacaine and bupivacaine, respectively, bolus dose was 1.4 mg/kg (95% CI 0.4 to 3.0, n=2978) and 1.0 mg/kg (95% CI 0.18 to 2.1, n=2724); infusion dose was 0.26 mg/kg/hour (95% CI 0.06 to 0.63, n=3579) and 0.2 mg/kg/hour (95% CI 0.06 to 0.5, n=3199); 24-hour dose was 7.75 mg/kg (95% CI 2.1 to 15.7, n=3579) and 6.0 mg/kg (95% CI 2.1 to 13.6, n=3223). Twenty-four hour doses exceeded the package insert recommended upper limit in 28% (range: 17%-40% based on maximum and minimum patient weights) of ropivacaine infusions and 51% (range: 45%-71%) of bupivacaine infusions. Toxicity occurred in 30 patients and was associated with high 24-hour dose, bilateral catheters, cardiac surgery, cytochrome P-450 inhibitors and hypoalbuminemia.

CONCLUSION

Practitioners frequently administer ropivacaine and bupivacaine above the package insert limits, at doses associated with toxicity. Patient safety would benefit from more specific recommendations to limit excessive dose and risk of toxicity.

Cooled versus conventional radiofrequency treatment of the genicular nerves for chronic knee pain: 12-month and cost-effectiveness results from the multicenter COCOGEN trial

BACKGROUND

Radiofrequency (RF) treatment of the genicular nerves reduces chronic knee pain in patients with osteoarthritis (OA) or persistent postsurgical pain (PPSP) after total knee arthroplasty (TKA). The objective of this study is to compare long-term outcomes of cooled and conventional RF and perform an economic evaluation.

METHODS

The COCOGEN trial is a double-blinded, non-inferiority, pilot, randomized controlled trial that compared the effects up to 12 months of cooled and conventional RF in patients with chronic knee pain suffering from OA or PPSP after TKA following a 1:1 randomization rate. Outcomes were knee pain, functionality, quality of life, emotional health, medication use, and adverse events. A trial-based economic evaluation was performed with a 12-month societal perspective. Here, the primary outcome was the incremental costs per quality-adjusted life year (QALY).

RESULTS

41 of the 49 included patients completed the 12-month follow-up. One patient in the PPSP cooled RF group had substantial missing data at 12-month follow-up. The proportion of patients with ≥50% pain reduction at 12 months was 22.2% (4/18) in patients treated with conventional RF versus 22.7% (5/22) in patients treated with cooled RF (p>0.05). There was a statistically significant difference in the mean absolute numerical rating scale at 12 months after cooled RF and conventional RF in patients with PPSP (p=0.02). Differences between other outcomes were not statistically significant. The health economic analysis indicated that cooled RF resulted in lower costs and improved QALYs compared with conventional RF in PPSP but not in OA. There were no serious adverse events.

CONCLUSIONS

Both RF treatments demonstrated in approximately 22% of patients a ≥50% pain reduction at 12 months. In patients with PPSP, contrary to OA, cooled RF seems to be more effective than conventional RF. Additionally, cooled RF has in patients with PPSP, as opposed to OA, greater effectiveness at lower costs compared with conventional RF.

TRIAL REGISTRATION NUMBER

NCT03865849.

Percutaneous auricular neuromodulation (nerve stimulation) for the treatment of pain following total knee arthroplasty: a randomized, double-masked, sham-controlled pilot study

BACKGROUND

Percutaneous auricular nerve stimulation (neuromodulation) is an analgesic technique involving the percutaneous implantation of multiple leads at various points on/around the ear followed by the delivery of electric current using an external pulse generator. A device is currently available within the USA cleared to treat symptoms from opioid withdrawal, and multiple reports suggest a possible postoperative analgesic effect. The current randomized, controlled pilot study was undertaken to (1) determine the feasibility and optimize the protocol for a subsequent definitive clinical trial and (2) estimate the treatment effect of auricular neuromodulation on postoperative pain and opioid consumption following total knee arthroplasty.

METHODS

Within the recovery room following primary, unilateral, total knee arthroplasty, an auricular neuromodulation device (NSS-2 Bridge, Masimo, Irvine, California, USA) was applied using three percutaneous leads and one ground electrode. Participants were randomized to 5 days of either electrical stimulation or sham stimulation in a double-masked fashion. Participants were discharged with the stimulator in situ and removed the disposable devices at home. The dual primary treatment effect outcome measures were the cumulative opioid use (oral oxycodone) and the mean of the "average" daily pain measured with the Numeric Rating Scale for the first 5 postoperative days.

RESULTS

During the first five postoperative days, oxycodone consumption in participants given active stimulation (n=15) was a median (IQR) of 4 mg (2-12) vs 13 mg (5-23) in patients given sham (n=15) treatment (p=0.039). During this same period, the average pain intensity in patients given active stimulation was a median (IQR) of 2.5 (1.5-3.3) vs 4.0 (3.6-4.8) in those given sham (p=0.014). Awakenings due to pain over all eight postoperative nights in participants given active stimulation was a median (IQR) of 5 (3-8) vs 11 (4-14) in those given sham (p<0.001). No device-related localized cutaneous irritation, systemic side effects, or other adverse events were identified.

CONCLUSIONS

Percutaneous auricular neuromodulation reduced pain scores and opioid requirements during the initial week after total knee arthroplasty. Given the ease of application as well as the lack of systemic side effects and reported complications, a definitive clinical trial appears warranted.

TRIAL REGISTRATION NUMBER

NCT05521516.

Plantar compartment block for hallux valgus surgery: a proof-of-concept anatomic and clinical study

BACKGROUND

Hallux valgus surgery is associated with moderate to severe postoperative pain. We hypothesized that a plantar compartment block may be a good technique for postoperative analgesia. We describe an anatomic approach to ultrasound-guided plantar compartment block and assess the clinical efficacy of the block for outpatient surgery.

METHODS

The anatomic study was aimed to describe the plantar compartment, using both dissection methods and imaging, and to define a volume of local anesthetic. Patients scheduled for hallux valgus surgery with a popliteal sciatic nerve block, and combined plantar compartment and peroneal blocks were included in the clinical study. Data on attaining the criteria for rapid exit from the outpatient center, duration of sensory and analgesic block, visual analog scale (VAS) values for postoperative pain at rest and during movement, and the consumption of morphine as rescue analgesia were recorded.

RESULTS

Plane-by-plane dissections and cross-sections were done in five cadaveric lower limbs. The medial calcaneal nerve divides into medial plantar and lateral plantar nerves in the upper part of the plantar compartment. These nerves were surrounded by 5 mL of colored gelatin, and 10 mL of injectates dye spread to the medial calcaneal branches. Thirty patients (26 women) were included in the clinical study. There were no failures of surgical block. Ninety per cent of patients successfully passed functional testing for ambulatory exit from the center within 5 hours (25th-75th centiles, 3.8-5.5 hours). The median duration of plantar compartment sensory block was 17.3 hours (10.5-21.5 hours), and the first request for rescue analgesic was 11.75 hours (10.5-23 hours) after surgery. The median VAS score for maximum pain reported within the 48-hour period was 2 (1-6). Twelve patients received 2.5 mg (0-5 mg) of morphine on day 1. Patients were highly satisfied and no adverse events were noted.

CONCLUSIONS

This anatomic description of the ultrasound-guided plantar compartment block reported the injection area to target the medial and lateral plantar nerves with 5 mL of local anesthetic. Normal walking without assistance is attained rapidly with this regional anesthesia technique, and the time to request postoperative analgesia after hallux valgus surgery is long.

TRIAL REGISTRATION NUMBER

NCT03815422.

Lessons learnt in evidence-based perioperative pain medicine: changing the focus from the medication and procedure to the patient

Over time, the focus of evidence-based acute pain medicine has shifted, from a focus on drugs and interventions (characterized by numbers needed to treat), to an appreciation of procedure-specific factors (characterized by guidelines and meta-analyses), and now anesthesiologists face the challenge to integrate our current approach with the concept of precision medicine. Psychometric and biopsychosocial markers can potentially guide clinicians on who may need more aggressive perioperative pain management, or who would respond particularly well to a given analgesic intervention. The challenge will be to identify an easily assessable set of parameters that will guide perioperative physicians in tailoring the analgesic strategy to procedure and patient.

Empirical guide to a safe thoracic paravertebral block based on dimensions of paravertebral space when ultrasound visualization is challenging

Although ultrasound (US) guidance is the mainstay technique for performing thoracic paravertebral blocks, situations arise when US imaging is limited due to subcutaneous emphysema or extremely deep structures. A detailed understanding of the anatomical structures of the paravertebral space can be strategic to safely and accurately perform a landmark-based or US-assisted approach. As such, we aimed to provide an anatomic roadmap to assist physicians. We examined 50 chest CT scans, measuring the distances of the bony structures and soft-tissue surrounding the thoracic paravertebral block at the 2nd/3rd (upper), 5th/6th (middle), and 9th/10th (lower) thoracic vertebral levels. This review of radiology records controlled for individual differences in body mass index, gender, and thoracic level. Midline to the lateral aspect of the transverse process (TP), the anterior-to-posterior distance of TP to pleura, and rib thickness range widely based on gender and thoracic level. The mean thickness of the TP is 0.9±0.1 cm in women and 1.1±0.2 cm in men. The best target for initial needle insertion from the midline (mean length of TP minus 2 SDs) distance would be 2.5 cm (upper thoracic)/2.2 cm (middle thoracic)/1.8 cm (lower thoracic) for females and 2.7 cm (upper)/2.5 cm (middle)/2.0 cm (lower thoracic) for males, with consideration that the lower thoracic region allows for a lower margin of error in the lateral dimension because of shorter TP. There are different dimensions for the key bony landmarks of a thoracic paravertebral block between males and females, which have not been previously described. These differences warrant adjustment of landmark-based or US-assisted approach to thoracic paravertebral space block for male and female patients.

Trends of liposomal bupivacaine utilization in major lower extremity total joint arthroplasty in the USA: a population-based study

INTRODUCTION

Liposomal bupivacaine has been marketed for the achievement of long-acting local or regional anesthesia after major lower extremity total joint arthroplasty. However, it is comparatively expensive and controversy remains regarding its ability to decrease healthcare costs. With mounting evidence suggesting non-superiority in efficacy, compared with plain bupivacaine, we sought to investigate trends in liposomal bupivacaine use and identify changes in practice.

METHODS

We identified adult patients from the Premier Healthcare Database who underwent elective total joint arthroplasty between 2012 and 2021. Prevalence and trends of liposomal bupivacaine utilization were compared on the individual patient and hospital levels. Log-rank tests were performed to assess the influence of location, teaching status, or hospital size on time to hospital-level liposomal bupivacaine termination.

RESULTS

Among 103,165 total joint arthroplasty cases, liposomal bupivacaine use increased between 2012 and 2015 (from 0.4% to 22.8%) and decreased by approximately 1%-3% annually thereafter (15.7% in 2021). Liposomal bupivacaine was ever used in approximately 60% of hospitals. Hospital-level initiation of liposomal bupivacaine use peaked in 2014 and decreased thereafter (from 32.8% in 2013 to 4.3% in 2021), while termination rates increased (from 1.4% in 2014 to 9.9% in 2019). Non-teaching hospitals and those located in the South and West regions were more likely to retain liposomal bupivacaine longer than teaching or Midwest/Northeast hospitals, respectively (p=0.023 and p=0.014).

DISCUSSION

Liposomal bupivacaine use peaked around 2015 and has been declining thereafter on individual patient and hospital levels. How these trends correlate with health outcomes and expenditures would be a strategic target for future research.

Iliopsoas plane block does not improve pain after primary total hip arthroplasty in the presence of multimodal analgesia: a single institution randomized controlled trial

BACKGROUND

The clinical analgesic efficacy of iliopsoas plane block remains a subject of discussion. This study aimed to assess the analgesic efficacy of iliopsoas plane block under general anesthesia using multimodal analgesia.

METHODS

Fifty-six adult patients who underwent elective primary hip arthroplasty were enrolled. Patients were randomized to receive either a single-shot iliopsoas plane block (10 mL 0.75% ropivacaine with 1:200 000 epinephrine) or a sham block (10 mL normal saline). All patients received general anesthesia, multimodal analgesia (preoperative buprenorphine patch, 5 µg/h), intraoperative intravenous dexamethasone (8 mg) and nefopam (20 mg), and round-the-clock acetaminophen and celecoxib. The primary outcome was the numeric rating scale pain score at rest 6 hour after surgery.

RESULTS

Iliopsoas plane block did not have a notable advantage over the sham block in terms of pain relief at rest, as assessed by the numeric rating scale score, 6 hour after total hip arthroplasty (iliopsoas plane block: median, 4.0; IQR, 2.0-5.8; sham: median, 5.5; IQR, 2.3-6.8; median difference, -1.0; 95% CI -2.0 to 0.0; p≥0.999). Linear mixed model analysis showed no differences in pain scores, opioid consumption, quadriceps strength, or quality of recovery between the groups.

CONCLUSIONS

Iliopsoas plane block did not improve postoperative analgesia following total hip arthroplasty under general anesthesia with a multimodal analgesic regimen. The blockade of sensory femoral branches supplying the anterior hip capsule using iliopsoas plane block may not yield additional benefits concerning patient outcomes in the aforementioned clinical context.

TRIAL REGISTRATION NUMBER

NCT05212038, https://clinicaltrials.gov/ct2/show/NCT05212038.

Differences in the association between epidural analgesia and length of stay by surgery type: an observational study

INTRODUCTION

Despite a decline in the use of thoracic epidural analgesia related in part to concerns for delayed discharge, it is unknown whether changes in length of stay (LOS) associated with epidural analgesia vary by surgery type. Therefore, we determined the degree to which the association between epidural analgesia (vs no epidural) and LOS differed by surgery type.

METHODS

We conducted an observational study using data from 1747 patients who had either non-emergent open abdominal, thoracic, or vascular surgery at a single tertiary academic hospital. The primary outcome was hospital LOS and the incidence of a prolonged hospital LOS defined as 21 days or longer. Secondary endpoints included escalation of care, 30-day all-cause readmission, and reason for epidural not being placed. The association between epidural status and dichotomous endpoints was examined using logistic regression.

RESULTS

Among the 1747 patients, 85.7% (1499) received epidural analgesia. 78% (1364) underwent abdominal, 11.5% (200) thoracic, and 10.5% (183) vascular surgeries. After adjustment for differences, receiving epidural analgesia (vs no epidural) was associated with a 45% reduction in the likelihood of a prolonged LOS (p<0.05). This relationship varied by surgery type: abdominal (OR 0.42, 95% CI 0.23 to 0.79, p<0.001), vascular (OR 1.66, 95% CI 0.17 to 16.1, p=0.14), and thoracic (OR 1.07, 95% CI 0.20 to 5.70, p=0.93). Among abdominal surgical patients, epidural analgesia was associated with a median decrease in LOS by 1.4 days and a 37% reduction in the likelihood of 30-day readmission (adjusted OR 0.63, 0.41 to 0.97, p<0.05). Among thoracic surgical patients, epidural analgesia was associated with a median increase in LOS by 3.2 days.

CONCLUSIONS

The relationship between epidural analgesia and LOS appears to be different among different surgical populations.

Differential nerve blockade to explain anterior thoracic analgesia without sensory blockade after an erector spinae plane block may be wishful thinking

Ultrasound-guided erector spinae plane block (ESPB) is currently used as a component of multimodal analgesic regimen in a multitude of indications but the mechanism by which it produces anterior thoracic analgesia remains a subject of controversy. This is primarily the result of ESPB's failure to consistently produce cutaneous sensory blockade (to pinprick and cold sensation) over the anterior hemithorax. Nevertheless, ESPB appears to provide 'clinically meaningful analgesia' in various clinical settings. Lately, it has been proposed that the discrepancy between clinical analgesia and cutaneous sensory blockade could be the result of differential nerve blockade at the level of the dorsal root ganglion. In particular, it is claimed that at a low concentration of local anesthetic, the C nerve fibers would be preferentially blocked than the Aδ nerve fibers. However, the proposal that isolated C fiber mediated analgesia with preserved Aδ fiber mediated cold and pinprick sensation after an ESPB is unlikely, has never been demonstrated and, thus, without sufficient evidence, cannot be attributed to the presumed analgesic effects of an ESPB.

Effects of combined dexamethasone and dexmedetomidine as adjuncts to peripheral nerve blocks: a systematic review with meta-analysis and trial sequential analysis

BACKGROUND/IMPORTANCE

The effects of combining dexamethasone and dexmedetomidine on block duration are unclear.

OBJECTIVE

To investigate the effects of combining dexamethasone and dexmedetomidine on block duration.

EVIDENCE REVIEW

Systematic review of randomized controlled trials (RCTs) from Medline, Embase, CENTRAL, CINAHL, the Web of Science, and BIOSIS until June 8, 2023. RCTs with adults undergoing surgery with a peripheral nerve block randomized to combined dexamethasone and dexmedetomidine versus placebo or other adjuncts were eligible. Primary outcome was duration of analgesia. We performed meta-analysis, trial sequential analysis, risk of bias-2, and Grading Recommendations Assessment, Development, and Evaluation assessment.

FINDINGS

We included 9 RCTs with 14 eligible comparisons. The combination of dexamethasone and dexmedetomidine was compared with placebo in three RCTs (173 participants), dexamethasone in seven (569 participants), and dexmedetomidine in four (281 participants). The duration of analgesia was likely increased with the combination versus placebo (mean difference 460 min, 95% CI 249 to 671) and versus dexmedetomidine (mean difference 388 min, 95% CI 211 to 565). The duration was likely similar with the combination versus dexamethasone (mean difference 50 min, 95% CI -140 to 239). The certainty of the evidence was moderate because most trials were at high risk of bias.

CONCLUSIONS

Combined dexamethasone and dexmedetomidine likely increased the duration of analgesia when compared with placebo and dexmedetomidine. The combination likely provided a similar duration of analgesia as dexamethasone. Based on this systematic review, it seems reasonable to use dexamethasone as the sole adjunct if the goal is to increase the duration of analgesia.

Perioperative pain management for cleft palate surgery: a systematic review and procedure-specific postoperative pain management (PROSPECT) recommendations

BACKGROUND/IMPORTANCE

Cleft palate surgery is associated with significant postoperative pain. Effective pain control can decrease stress and agitation in children undergoing cleft palate surgery and improve surgical outcomes. However, limited evidence often results in inadequate pain control after cleft palate surgery.

OBJECTIVES

The aim of this review was to evaluate the available evidence and to develop recommendations for optimal pain management after cleft palate surgery using procedure-specific postoperative pain management (PROSPECT) methodology.

EVIDENCE REVIEW

MEDLINE, Embase, and Cochrane Databases were searched for randomized controlled trials and systematic reviews assessing pain in children undergoing cleft palate repair published in English language from July 2002, through August 2023.

FINDINGS

Of 1048 identified studies, 19 randomized controlled trials and 4 systematic reviews met the inclusion criteria. Interventions that improved postoperative pain, and are recommended, include suprazygomatic maxillary nerve block or palatal nerve block (if maxillary nerve block cannot be performed). Addition of dexmedetomidine to local anesthetic for suprazygomatic maxillary nerve block or, alternatively, as intravenous administration perioperatively is recommended. These interventions should be combined with a basic analgesic regimen including acetaminophen and nonsteroidal anti-inflammatory drugs. Of note, pre-incisional local anesthetic infiltration and dexamethasone were administered as a routine in several studies, however, because of limited procedure-specific evidence their contribution to pain relief after cleft palate surgery remains unknown.

CONCLUSION

The present review identified an evidence-based analgesic regimen for cleft palate surgery in pediatric patients.

PROSPERO REGISTRATION NUMBER

CRD42022364788.

Comparison analysis of safety outcomes and the rate of subsequent spinal procedures between interspinous spacer without decompression versus minimally invasive lumbar decompression

INTRODUCTION

Treatment for degenerative lumbar spinal stenosis (LSS) typically begins with conservative care and progresses to minimally invasive procedures, including interspinous spacer without decompression or fusion (ISD) or minimally invasive lumbar decompression (MILD). This study examined safety outcomes and the rate of subsequent spinal procedures among LSS patients receiving an ISD versus MILD as the first surgical intervention.

METHODS

100% Medicare Standard Analytical Files were used to identify patients with an ISD or MILD (first procedure=index date) from 2017 to 2021. ISD and MILD patients were matched 1:1 using propensity score matching based on demographics and clinical characteristics. Safety outcomes and subsequent spinal procedures were captured from index date until end of follow-up. Cox models were used to analyze rates of subsequent surgical interventions, LSS-related interventions, open decompression, fusion, ISD, and MILD. Cox models were used to assess postoperative complications during follow-up and logistic regression to analyze life-threatening complications within 30 days of index procedure.

RESULTS

A total of 3682 ISD and 5499 MILD patients were identified. After matching, 3614 from each group were included in the analysis (mean age=74 years, mean follow-up=20.0 months). The risk of undergoing any intervention, LSS-related intervention, open decompression, and MILD were 21%, 28%, 21%, and 81% lower among ISD compared with MILD patients. Multivariate analyses showed no significant differences in the risk of undergoing fusion or ISD, experiencing postoperative complications, or life-threatening complications (all p≥0.241) between the cohorts.

CONCLUSIONS

These results showed ISD and MILD procedures have an equivalent safety profile. However, ISDs demonstrated lower rates of open decompression and MILD.

Incidence and characteristics of chronic postsurgical pain at 6 months after total mastectomy under pectoserratus and interpectoral plane block combined with general anesthesia: a prospective cohort study

INTRODUCTION

Chronic postsurgical pain (CPSP) occurs in 20%-30% of patients who undergo total mastectomy (TM) performed under general anesthesia alone and significantly affects the quality of life. Pectoserratus and interpectoral plane block have been reportedly combined with general anesthesia to control immediate postoperative pain after TM. Our prospective cohort study aimed to evaluate the incidence of CPSP after TM when pectoserratus and interpectoral plane block were combined with general anesthesia.

METHODS

We recruited adult women scheduled to undergo TM for breast cancer. Patients planned for TM with flap surgery, those who underwent breast surgery in the past 5 years, or those presenting with residual chronic pain after prior breast surgery were excluded. After general anesthesia induction, an anesthesiologist performed pectoserratus and interpectoral plane block with a ropivacaine (3.75 mg/mL) and clonidine (3.75 µg/mL) in 40 mL of 0.9% sodium chloride. The primary endpoint was the occurrence of CPSP-defined as pain with a Numeric Rating Scale Score of ≥3, either at the breast surgical site and/or at axilla, without other identifiable causes-evaluated during a pain medicine consultation at 6 months post TM.

RESULTS

Overall, 43/164 study participants had CPSP (26.2%; 95% CI: 19.7 to 33.6); of these, 23 had neuropathic type of pain (53.5%), 19 had nociceptive (44.2%), and 1 had mixed (2.3%) type of pain.

CONCLUSION

Although postoperative analgesia has significantly improved in the last decade, there is still need for improvement to reduce CPSP after oncologic breast surgery.

TRIAL REGISTRATION NUMBER

NCT03023007.

What evidence is needed to inform postoperative opioid consumption guidelines? A cohort study of the Michigan Surgical Quality Collaborative

INTRODUCTION

To balance adequate pain management while minimizing opioid-related harms after surgery, opioid prescribing guidelines rely on patient-reported use after surgery. However, it is unclear how many patients are required to develop precise guidelines. We aimed to compare patterns of use, required sample size, and the precision for patient-reported opioid consumption after common surgical procedures.

METHODS

We analyzed procedure-specific 30-day opioid consumption data reported after discharge from 15 common surgical procedures between January 2018 and May 2019 across 65 hospitals in the Michigan Surgical Quality Collaborative. We calculated proportions of patients using no pills and the estimated number of pills meeting most patients' needs, defined as the 75th percentile of consumption. We compared several methods to model consumption patterns. Using the best method (Tweedie), we calculated sample sizes required to identify opioid consumption within a 5-pill interval and estimates of pills to meet most patients' needs by calculating the width of 95% CIs.

RESULTS

In a cohort of 10,688 patients, many patients did not consume any opioids after all types of procedures (range 20%-40%). Most patients' needs were met with 4 pills (thyroidectomy) to 13 pills (abdominal hysterectomy). Sample sizes required to estimate opioid consumption within a 5-pill wide 95% CI ranged from 48 for laparoscopic appendectomy to 188 for open colectomy. The 95% CI width for estimates ranged from 0.7 pills for laparoscopic cholecystectomy to 7.0 pills for ileostomy/colostomy.

CONCLUSIONS

This study demonstrates that profiles of opioid consumption share more similarities than differences for certain surgical procedures. Future investigations on patient-reported consumption are required for procedures not currently included in prescribing guidelines to ensure surgeons and perioperative providers can appropriately tailor recommendations to the postoperative needs of patients.

Local anesthetic dosing and toxicity of pediatric truncal catheters: a narrative review of published practice

BACKGROUND/IMPORTANCE

Despite over 30 years of use by pediatric anesthesiologists, standardized dosing rates, dosing characteristics, and cases of toxicity of truncal nerve catheters are poorly described.

OBJECTIVE

We reviewed the literature to characterize dosing and toxicity of paravertebral and transversus abdominis plane catheters in children (less than 18 years).

EVIDENCE REVIEW

We searched for reports of ropivacaine or bupivacaine infusions in the paravertebral and transversus abdominis space intended for 24 hours or more of use in pediatric patients. We evaluated bolus dosing, infusion dosing, and cumulative 24-hour dosing in patients over and under 6 months. We also identified cases of local anesthetic systemic toxicity and toxic blood levels.

FINDINGS

Following screening, we extracted data from 46 papers with 945 patients.Bolus dosing was 2.5 mg/kg (median, range 0.6-5.0; n=466) and 1.25 mg/kg (median, range 0.5-2.5; n=294) for ropivacaine and bupivacaine, respectively. Infusion dosing was 0.5 mg/kg/hour (median, range 0.2-0.68; n=521) and 0.33 mg/kg/hour (median, range 0.1-1.0; n=423) for ropivacaine and bupivacaine, respectively, consistent with a dose equivalence of 1.5:1.0. A single case of toxicity was reported, and pharmacokinetic studies reported at least five cases with serum levels above the toxic threshold.

CONCLUSIONS

Bolus doses of bupivacaine and ropivacaine frequently comport with expert recommendations. Infusions in patients under 6 months used doses associated with toxicity and toxicity occurred at a rate consistent with single-shot blocks. Pediatric patients would benefit from specific recommendations about ropivacaine and bupivacaine dosing, including age-based dosing, breakthrough dosing, and intermittent bolus dosing.

Role of supplemental regional blocks on postoperative neurocognitive dysfunction after major non-cardiac surgeries: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND/IMPORTANCE

Postoperative neurocognitive dysfunction (PNCD) is a frequent and preventable complication after surgery. The large high-quality evidence for the efficacy of supplemental regional analgesia blocks (RAB) for preventing PNCD is still elusive.

OBJECTIVE

The objective of this meta-analysis was to evaluate the effect of RAB versus standard anesthesia care on the incidence of PNCD in adult patients undergoing major non-cardiac surgery.

EVIDENCE REVIEW

PubMed, EMBASE, Scopus, and the Cochrane Central Registers of Controlled Trials (CENTRAL) were searched for randomized controlled trials (RCTs) from 2017 until June 2022. The primary outcome was the incidence of PNCD within 1 month of surgery. A random-effects model with an inverse variance method was used to pool results, and OR and mean differences were calculated for dichotomous and continuous outcomes. Various exploratory subgroup analyses were performed to explore the possibility of the association between the various patient, technique, and surgery-related factors. Grading of Recommendation, Assessment, Development, and Evaluation guidelines were used to determine the certainty of evidence.

FINDINGS

Twenty-six RCTs comprizing 4414 patients were included. The RAB group was associated with a significant reduction in the incidence of PNCD with an OR of 0.46 (95% CI 0.35 to 0.59; p<0.00001; I2=28%) compared with the control group (moderate certainty). Subgroup analysis exhibited that the prophylactic efficacy of RAB persisted for both delirium and delayed neurocognitive recovery.

CONCLUSIONS

Current evidence suggests that supplemental RAB are beneficial in preventing PNCD in patients after major non-cardiac surgery.

PROSPERO REGISTRATION NUMBER

CRD42022338820.

Financial model for a transitional pain service at a large tertiary academic center in the USA

Approximately 1 in 10 patients undergoing surgery is considered at high risk for poor pain and opioid-related outcomes due to chronic pain or persistent opioid use prior to surgery, leading to increased hospital lengths of stay, emergency department visits, hospital readmissions, and worse long-term outcomes. Multidisciplinary transitional pain services (TPSs) have been shown to effectively identify and optimize high-risk patients before surgery, leading to a reduction in healthcare utilization. We conducted a series of semistructured interviews, a literature search, and a financial analysis to develop a reproducible business case for establishing a TPS. These interviews involved discussions with clinicians and administrators at Michigan Medicine, as well as leaders of TPS initiatives at peer institutions across the USA and Canada. The aim was to understand possible operational structures and potential sources of revenue and cost savings that needed inclusion in our model. Subsequently, the authors developed a modifiable financial modeling tool, which is freely available for download and adaptable to any healthcare institution. The model suggests that the primary source of cost savings can be attributed to a reduction in length of stay. Furthermore, several operational options exist for incorporating a TPS that performs at breakeven or positive net profit. This tool and these findings are important for informing health systems of operational and financial considerations when implementing a TPS program. Future research should evaluate this financial tool's reproducibility in community health system contexts.

Alcohol use disorder in the perioperative period: a summary and recommendations for anesthesiologists and pain physicians

Excessive alcohol consumption and alcohol use disorder (AUD) increase the risk of perioperative morbidity and mortality. Aspiration, malnutrition, coagulopathies, seizures, and hemodynamic alterations are only a few of the major concerns related to acute alcohol intoxication and AUD. There are also numerous physiological effects, changes in medication metabolism and pharmacology, and adverse events related to chronic alcohol consumption. These are all important considerations for the anesthesiologist in the perioperative management of a patient with AUD. Pain perception and thresholds are altered in patients with acute and chronic alcohol use. Medications used to manage AUD symptoms, particularly naltrexone, can have significant perioperative implications. Patients on naltrexone who continue or stop this medication in the perioperative period are at an increased risk for undertreated pain or substance use relapse. This review highlights key considerations for the anesthesiologist and pain physician in the perioperative management of patients with active AUD (or those in recovery). It discusses the effects of acute and chronic alcohol use on pain perception and thresholds, provides guidance on the perioperative management of naltrexone and low-dose naltrexone, and reviews a multimodal approach to pain management.

Impact of a Transitional Pain Service on postoperative opioid trajectories: a retrospective cohort study

INTRODUCTION

It has been well described that a small but significant proportion of patients continue to use opioids months after surgical discharge. We sought to evaluate postdischarge opioid use of patients who were seen by a Transitional Pain Service compared with controls.

METHODS

We conducted a retrospective cohort study using administrative data of individuals who underwent surgery in Ontario, Canada from 2014 to 2018. Matched cohort pairs were created by matching Transitional Pain Service patients to patients of other academic hospitals in Ontario who were not enrolled in a Transitional Pain Service. Segmented regression was performed to assess changes in monthly mean daily opioid dosage.

RESULTS

A total of 209 Transitional Pain Service patients were matched to 209 patients who underwent surgery at other academic centers. Over the 12 months after surgery, the mean daily dose decreased by an estimated 3.53 morphine milligram equivalents (95% CI 2.67 to 4.39, p<0.001) per month for the Transitional Pain Service group, compared with a decline of only 1.05 morphine milligram equivalents (95% CI 0.43 to 1.66, p<0.001) for the controls. The difference-in-difference change in opioid use for the Transitional Pain Service group versus the control group was -2.48 morphine milligram equivalents per month (95% CI -3.54 to -1.43, p=0.003).

DISCUSSION

Patients enrolled in the Transitional Pain Service were able to achieve opioid dose reduction faster than in the control cohorts. The difficulty in finding an appropriate control group for this retrospective study highlights the need for future randomized controlled trials to determine efficacy.

Efficacy of the intertransverse process block: single or multiple injection? A randomized, non-inferiority, blinded, cross-over trial in healthy volunteers

INTRODUCTION

The intertransverse process block is increasingly used to ameliorate postoperative pain following a plethora of surgical procedures involving the thoracic wall. Nevertheless, the optimal approach and cutaneous extent of the sensory block are currently unknown. We aimed to further describe the intertransverse process block, single injection versus multiple injection, and we hypothesized that the single-injection intertransverse process block is a non-inferior technique.

METHODS

Twelve healthy male volunteers were cross-over randomized to receive either single-injection intertransverse process block with 21 mL ropivacaine 7.5 mg/mL, including two sham injections, at the thoracic level T4/T5 or multiple-injection intertransverse process block with three injections of 7 mL ropivacaine 7.5 mg/mL at the thoracic levels T2/T3, T4/T5 and T6/T7 at the first visit. At the second visit, the other technique was applied on the contralateral hemithorax. A non-inferiority margin of 1.5 anesthetized thoracic dermatomes was chosen.

RESULTS

The mean difference (95% CI) in the number of anesthetized thoracic dermatomes was 0.82 (-0.41 to 2.05) pnon-inf<0.01 indicating non-inferiority favoring the single-injection technique.Both techniques anesthetized the ipsilateral thoracic wall and demonstrated contralateral cutaneous involvement to a variable extent. The multiple-injection intertransverse process block anesthetized a significantly larger cutaneous area on the posterior hemithorax and decreased mean arterial pressure at 30 and 60 min postblock application. Thoracic thermography showed no intermodality temperature differences yet compared with baseline temperatures both techniques showed significant differences.

CONCLUSIONS

Single-injection intertransverse process block is non-inferior to multiple injection in terms of anesthetized thoracic dermatomes. Both techniques generally anesthetize the hemithoracic wall to a variable extent.

EU CLINICAL TRIALS REGISTER

2022-501312-34-01.

Intraoperative landmark-based genicular nerve block versus periarticular infiltration for postoperative analgesia in total knee arthroplasty: a randomized non-inferiority trial

INTRODUCTION

Genicular nerve blocks (GNBs) are an emerging technique that have been used as a part of multimodal analgesia for total knee arthroplasty. The efficacy of intraoperative landmark-based GNBs, a recently introduced technique, has been established. We hypothesized that it would provide non-inferior postoperative analgesia compared with periarticular infiltration (PAI) when combined with continuous adductor canal block.

METHODS

This study randomized 140 patients undergoing total knee arthroplasty to receive either intraoperative landmark-based GNB (GNB group) or PAI (PAI group), with 139 completing the study. The primary outcomes were the pain scores at rest and during movement at 12 hours postoperatively on an 11-point Numerical Rating Scale; the non-inferiority margin was 1. Pain scores at additional time points, intravenous morphine consumption, time to first rescue analgesia, functional performance and muscle strength tests, and sleep disturbance were also assessed.

RESULTS

At 12 hours postoperatively, the PAI and GNB groups had median resting pain scores of 0 (0-2) and 0 (0-2), respectively. The median difference was 0 (95% CI -0.4 to 0.4, p=1), with the 95% CI upper limit below the prespecified non-inferiority margin. The median pain score during movement was 1.5 (0-2.3) and 2 (1-3.1) in the PAI and GNB groups, respectively. The median difference was 0.9 (95% CI 0.3 to 1.6, p=0.004), failing to demonstrate non-inferiority. The GNB group had higher intravenous morphine consumption at 12 hours postoperatively and a shorter time to first rescue analgesia.

CONCLUSIONS

GNB compared with PAI provides non-inferior resting pain relief. Non-inferiority was not established for pain during movement.

TRIAL REGISTRATION NUMBER

TCTR20220406001 (www.thaiclinicaltrials.org).

Effect of preoperative patient education and simulated mouth breathing training on opioid requirements in the post-anesthesia care unit after nasal surgery: a randomized controlled study

BACKGROUND

A simulated education, prior to surgery about postoperative nasal stuffiness and ease of breathing through the mouth may help patients tolerate discomfort after nasal surgery. This study aimed to investigate the effect of preoperative simulated education on immediate postoperative opioid requirements in patients undergoing elective nasal surgery.

METHODS

This randomized controlled trial of 110 patients undergoing nasal surgery randomly allocated patients into either a control (group C) or an education group (group E). One day before surgery, patients in group E were intensively trained to breathe through the mouth by using a nasal clip, with informative explanations about inevitable nasal obstruction and discomfort following surgery. Patients in group C were provided with routine preoperative information. Total intravenous anesthesia (TIVA) with propofol and remifentanil was used for anesthesia. No further opioid was used for analgesia intraoperatively. The primary outcome was index opioid (fentanyl) requirements at the post-anesthesia recovery unit (PACU). Secondary outcomes were emergence agitation, pain scores at the PACU, and postoperative recovery using the Quality of Recovery-15 (QoR15-K).

RESULTS

The rate of opioid use in the PACU was 51.0% in the group E and 39.6% in the group C (p = 0.242). Additional request for analgesics other than index opioid was not different between the groups. Emergence agitation, postoperative pain severity, and QoR15-K scores were comparable between the groups.

CONCLUSION

Preoperative education with simulated mouth breathing in patients undergoing nasal surgery did not reduce opioid requirements.

TRIAL REGISTRATION

KCT0006264; 16/09/2021; Clinical Research Information Services ( https://cris.nih.go.kr ).

Anterior quadratus lumborum block for analgesia after living-donor renal transplantation: a double-blinded randomized controlled trial

INTRODUCTION

Limited non-opioid analgesic options are available for managing postoperative pain after renal transplantation. We aimed to investigate whether the unilateral anterior quadratus lumborum (QL) block would reduce postoperative opioid consumption after living-donor renal transplantation in the context of multimodal analgesia.

METHODS

Eighty-eight adult patients undergoing living-donor renal transplantation were randomly allocated to receive the unilateral anterior QL block (30 mL of ropivacaine 0.375%) or sham block (normal saline) on the operated side before emergence from anesthesia. All patients received standard multimodal analgesia, including the scheduled administration of acetaminophen and fentanyl via intravenous patient-controlled analgesia. The primary outcome was the total opioid consumption during the first 24 hours after transplantation. The secondary outcomes included pain scores, time to first opioid administration, cutaneous distribution of sensory blockade, motor weakness, nausea/vomiting, quality of recovery scores, time to first ambulation, and length of hospital stay.

RESULTS

The total opioid consumption in the first 24 hours after transplantation did not differ significantly between the intervention and control groups (median (IQR), 160.5 (78-249.8) vs 187.5 (93-309) oral morphine milligram equivalent; median difference (95% CI), -27 (-78 to 24), p=0.29). No differences were observed in the secondary outcomes.

CONCLUSIONS

The anterior QL block did not reduce opioid consumption in patients receiving multimodal analgesia after living-donor renal transplantation. Our findings do not support the routine administration of the anterior QL block in this surgical population.

TRIAL REGISTRATION NUMBER

NCT04908761.

Clavipectoral fascia plane block spread: an anatomical study

BACKGROUND

The clavipectoral fascia plane block (CPB) is a novel anesthetic management strategy proposed by Valdes-Vilches for clavicle fractures. This study aimed to investigate the distribution of the injected solution around the clavicle and the surrounding tissues.

METHODS

Twelve clavicle samples were acquired from six cadavers. CPB was conducted using a 20 mL solution comprising methylene blue and iodinated contrast agent to improve visibility of the injected substance's dispersion. Methylene blue spread was assessed through anatomical dissection across distinct planes (subcutaneous, superficial muscular, deep muscular, and periosteal layers of the clavicle) in five cadavers. For the purpose of comparing methylene blue distribution, CT scans were performed on three cadavers.

RESULTS

Methylene blue was detected in the medial, intermediate, and lateral supraclavicular nerves, as well as superficial muscles including the deltoid, trapezius, sternocleidomastoid, and pectoralis major. However, no staining was observed in the deep muscle plane, including the subclavius, pectoralis minor, and clavipectoral fascia (CPF). Anterosuperior periosteum exhibited staining in 54% of surface, while only 4% of the posteroinferior surface. CT images displayed contrast staining in anterosuperior periclavicular region, consistent with observations from sagittal sections and anatomical dissections.

CONCLUSION

The CPB effectively distributes the administered solution in the anterosuperior region of the clavicular periosteum, superficial muscular plane, and supraclavicular nerves. However, it does not affect the posteroinferior region of the clavicular periosteum or the deep muscular plane, including the CPF.

Comparison of injectate spread and nerve coverage between single-injection intertransverse process block and paravertebral block at the T2 level: a cadaveric study

BACKGROUND

We compared the spread of an injectate into the thoracic sympathetic chain resulting from a single-injection intertransverse process (ITP) block with that of a single-injection PV block at the T2 level.

METHODS

Sixteen soft-embalmed cadavers were used. The right hemithorax was randomly allocated to receive either an ultrasound-guided single-injection ITP block or ultrasound-guided single-injection PV block at the T2 vertebral level, with the opposite block administered to the other side. Approximately 10 mL of latex dye solution was injected into each hemithorax using a random allocation technique. The presence of dye at the nerve root in the sympathetic chain and intercostal nerves at the injection and additional levels was examined by dissection.

RESULTS

The injectate spread into the T2 sympathetic ganglion on both ITP (11/16, 68.8%) and PV (16/16, 100%) blocks. The ITP block demonstrated greater uniformity of dye staining in both the dorsal rami and dorsal root ganglion, which contrasts with the less consistent staining outcomes of the PV block in these regions.

CONCLUSIONS

At the T2 level, we observed a lower efficacy of the ITP block for analgesic coverage of the sympathetic nerve. This suggested a potential preference by clinicians for the application of the T2 PV block over the ITP block, specifically for the management of sympathetically maintained pain in the upper extremities. In addition, our findings may hint at the potential advantages of the ITP block in specific clinical contexts where targeted nerve involvement, such as the medial branch block or dorsal root ganglion block, is sought.