Search

Background: This study assessed the cost-effectiveness of ultrasound (US) vs nerve stimulation (NS) guidance for continuous sciatic nerve block in Danish elective patients undergoing major foot and ankle surgery.Methods: > A cost-effectiveness analysis was conducted alongside a randomized controlled trial. A total of 100 consecutive patients were randomly assigned to either traditional electrical NS or US technique for catheter insertion guidance. Information on effects and costs were collected prospectively. An incremental cost-effectiveness ratio (ICER) was calculated as the extra cost per extra successful nerve block. The robustness of the ICER was investigated using 4000 non-parametric bias-corrected bootstrap replicates to calculate the likelihood that US leads to better effect and lower costs compared with NS guidance.Results: The mean ICER was negative, indicating that US was a dominating technology providing both higher quality and lower costs. The likelihood of US being more effective and cheaper than NS was estimated to 84.7%.Conclusions: In this trial, US was cost-effective. Assuming that the results are fairly generalizable, US should be the preferred catheter insertion technique in larger anaesthesia departments. [ABSTRACT FROM AUTHOR]

Background: Dorsal root ganglion stimulation (DRGS) is an established method for treating persistent and severe pain conditions. However, performing DRGS has significant challenges. Current DRGS systems are expensive, hindering accessibility for many patients and health care systems. Additionally, placing DRGS devices requires specialized training in epidural techniques and lead anchoring methods. Technical and financial requirements also limit the clinical applicability and availability of DRGS., Objectives: This study evaluated the feasibility of a new method for rapidly delivering near- DRG stimulation in human cadavers. The method involves a fluoroscopy-guided transforaminal approach using a fully implantable, injectable electrode, and its associated delivery system., Study Design: A human cadaver feasibility study., Setting: A cadaver laboratory., Methods: In this study, 3 anesthesiologist pain physicians received training on the injectable electrode device and delivery system using spine phantom models. They then applied the device's associated implantation techniques to 2 adult male cadavers. In the first cadaver, a single injectable electrode was placed near the left L2 lumbar DRG. In the second cadaver, injectable electrodes were placed near the left L1 and L2 DRG levels, and a benchmark DRGS device was installed at the left L1 level using fluoroscopic guidance. A careful anatomical dissection was then performed for each implanted device., Results: The stimulating contacts of the injectable electrodes were accurately positioned within one mm of the DRG at the lumbar L1 and L2 levels in both cadavers. The distances of both the injectable lead and benchmark DRGS device at the L1 level were measured as one mm from the posterior aspect of the DRG., Limitations: The findings of this study are based on anatomical examinations of a limited number of human cadavers and may not fully represent living human anatomy., Conclusions: To our knowledge, this feasibility cadaver study is the first of its kind to examine the accuracy and efficiency of a fluoroscopy-guided transforaminal approach to place injectable electrodes near the DRG. These promising results suggest that this method could be a viable alternative to existing DRGS techniques, warranting further investigation into its clinical potential.

Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Background/Objectives: The intermediate femoral cutaneous nerve (IFCN), the saphenous nerve, and the medial femoral cutaneous nerve (MFCN) innervate the skin of the anteromedial knee region. However, it is unknown whether the MFCN has a deeper innervation. This would be relevant for total knee arthroplasty (TKA) that intersects deeper anteromedial genicular tissue layers. Primary aim: to investigate deeper innervation of the anterior and posterior MFCN branches (MFCN-A and MFCN-P). Secondary aim: to investigate MFCN innervation of the skin covering the anteromedial knee area and medial parapatellar arthrotomy used for TKA. Methods: This study consists of (1) a dissection study and (2) unpublished data and post hoc analysis from a randomized controlled double-blinded volunteer trial (EudraCT number: 2020-004942-12). All volunteers received bilateral active IFCN blocks (nerve block round 1) and saphenous nerve blocks (nerve block round 2). In nerve block round 3, all volunteers were allocated to a selective MFCN-A block. Results: (1) The MFCN-A consistently innervated deeper structures in the anteromedial knee region in all dissected specimens. No deep innervation from the MFCN-P was observed. (2) Sixteen out of nineteen volunteers had an unanesthetized skin gap in the anteromedial knee area and eleven out of the nineteen volunteers had an unanesthetized gap on the skin covering the medial parapatellar arthrotomy before the active MFCN-A block. The anteromedial knee area and medial parapatellar arthrotomy was completely anesthetized after the MFCN-A block in 75% and 82% of cases, respectively. Conclusions: The MFCN-A shows consistent deep innervation in the anteromedial knee region and the area of MFCN-A innervation overlaps the skin area covering the medial parapatellar arthrotomy. Further trials are mandated to investigate whether an MFCN-A block translates into a clinical effect on postoperative pain after total knee arthroplasty or can be used for diagnosis and interventional pain management for chronic neuropathic pain due to damage to the MFCN-A during surgery.

Objective: The utility of single-injection and continuous peripheral nerve blocks is limited by short duration of analgesia and catheter-related complications, respectively. This double-blind, multicenter trial evaluated the efficacy, safety, and pharmacokinetics of single-injection, ultrasound-guided brachial plexus block (BPB) with liposomal bupivacaine (LB) added to a standardized pain management protocol for shoulder surgery., Methods: Adults undergoing total shoulder arthroplasty or rotator cuff repair were randomized to receive LB 133 mg, LB 266 mg (pharmacokinetic and safety analyses only), or placebo, added to a standardized analgesia protocol. The primary end point was area under the curve (AUC) of visual analog scale pain intensity scores through 48 hours postsurgery. Secondary end points were total opioid consumption, percentage of opioid-free patients, and time to first opioid rescue through 48 hours. Pharmacokinetic samples were collected through 120 hours and on days 7 and 10. Adverse events were documented., Results: One hundred fifty-five patients received treatment (LB 133 mg, N = 69; LB 266 mg, N = 15; placebo, N = 71). BPB with LB 133 mg was associated with significantly improved AUC of pain scores (least squares mean [SE] = 136.4 [12.09] vs 254.1 [11.77], P < 0.0001), opioid consumption (least squares mean [SE] = 12.0 [2.27] vs 54.3 [10.05] mg, P < 0.0001), median time to opioid rescue (4.2 vs 0.6 h, P < 0.0001), and percentage of opioid-free patients (treatment difference = 0.166, 95% confidence interval = 0.032-0.200, P = 0.008) through 48 hours vs placebo. Adverse event incidence was comparable between groups., Conclusions: Single-injection BPB with LB 133 mg provided analgesia through 48 hours postsurgery with reduced opioid use compared with placebo after shoulder surgery., (© 2019 American Academy of Pain Medicine.)

Background: Percutaneous nephrolithotomy (PNL) is associated with severe postoperative pain. The current study aimed to investigate the analgesic efficacy of transmuscular quadratus lumborum (TQL) block for patients undergoing PNL surgery., Methods: Sixty patients were enrolled in this single centre study. The multimodal analgesic regime consisted of oral paracetamol 1 g and i.v. dexamethasone 4 mg before surgery and i.v. sufentanil 0.25 μg kg -1 30 min before emergence. After operation, patients received paracetamol 1 g regularly at 6 h intervals. Subjects were allocated to receive a preoperative TQL block with either ropivacaine 0.75%, 30 ml (intervention) or saline 30 ml (control). Primary outcome was oral morphine equivalent (OME) consumption 0-6 h after surgery. Secondary outcomes were OME consumption up to 24 h, pain scores, time to first opioid, time to first ambulation, and hospital length of stay. Results were reported as mean (standard deviation) or median (inter-quartile range)., Results: Morphine consumption was lower in the intervention group at 6 h after surgery (7.2 [8.7] vs 90.6 [69.9] mg OME, P<0.001) and at 24 h (54.0 [36.7] vs 126.2 [85.5] mg OME, P<0.001). Time to first opioid use was prolonged in the intervention group (678 [285-1020] vs 36 [19-55] min, P<0.0001). Both the time to ambulation (302 [238-475] vs 595 [345-925] min, P<0.004) and length of stay (2.0 [0.8] vs 3.0 [1.2] days, P≤0.001) were shorter in the intervention group., Conclusions: This is the first blinded, RCT that confirms that unilateral TQL block reduces postoperative opioid consumption and hospital length of stay. Further study is required for confirmation and dose optimisation., Clinical Trial Registration: NCT02818140., (Copyright © 2019 British Journal of Anaesthesia. All rights reserved.)

Postoperative pain after laparoscopic cholecystectomy can be severe. Despite multimodal analgesia regimes, administration of high doses of opioids is often necessary. This can further lead to several adverse effects such as drowsiness and respiratory impairment as well as postoperative nausea and vomiting. This will hinder early mobilization and discharge of the patient from the day surgery setting and is suboptimal in an Early Recovery after Surgery setting. The ultrasound-guided Erector Spinae Plane (ESP) block is a novel truncal interfascial block technique providing analgesia of the thoracic or abdominal segmental innervation depending on the level of administration. Local anesthetic penetrates anteriorly presumably through the costotransverse foramina to the paravertebral space. We demonstrate the analgesic efficacy of the ESP block in a case series of three patients scheduled for ambulatory laparoscopic cholecystectomy.

Background: The spread of injectate resulting from a transmuscular quadratus lumborum (TQL) block and a transverse oblique paramedian (TOP) TQL block has never been examined. The aim of this cadaveric study was to investigate by which pathway the injectate spreads cephalad into the thoracic paravertebral space and which nerves were dyed by the injectate cephalad and caudad to the diaphragm when performing a TQL and a TOP TQL block. We also aimed to investigate whether the thoracic and lumbar sympathetic trunks as well as the lumbar plexus were covered by the injectate., Methods: Ultrasound-guided bilateral TQL and TOP TQL injections were administered in 8 cadavers. A total of 16 injections were performed. With the TQL injection, the curvilinear transducer was oriented in the transverse plane above the iliac crest at the posterior axillary line to identify the Shamrock sign. With the TOP TQL injection, the same transducer was placed with a TOP orientation 3 cm lateral to the L2 spinous process to identify the L2 transverse process and the adjoining quadratus lumborum muscle. For both techniques, the needle was advanced in-plane to the transducer, with the end point in the interfascial plane between the quadratus lumborum and psoas major muscles. Thirty milliliters of dye solution was injected bilaterally for each technique. The spread of the dye was evaluated by subsequent dissection., Results: In all successful injections, the dye was seen to spread into the thoracic paravertebral space and the intercostal spaces to surround the somatic nerves and the thoracic sympathetic trunk. The main pathway of spread of injectate was posterior to the medial and lateral arcuate ligaments. Caudad to the diaphragm, the injected dye surrounded the subcostal, iliohypogastric, and ilioinguinal nerves in all cases, whereas the genitofemoral and lateral femoral cutaneous nerves were dyed in a varying degree. No dye was seen to surround the lumbar plexus, femoral nerve, or lumbar sympathetic trunk. The pattern of spread was similar with the TQL and TOP TQL injections., Conclusions: The spread of injectate with the TQL and TOP TQL approaches is cephalad from the lumbar point of administration between the quadratus lumborum and psoas major muscles, predominantly via a pathway posterior to the arcuate ligaments and into the thoracic paravertebral space to reach the somatic nerves and the thoracic sympathetic trunk in the intercostal and paravertebral spaces. The lumbar plexus and lumbar sympathetic trunk are not affected.

Background: The currently best-established ultrasound-guided lumbar plexus block (LPB) techniques use a paravertebral location of the probe, such as the lumbar ultrasound trident (LUT). However, paravertebral ultrasound scanning can provide inadequate sonographic visibility of the lumbar plexus in some patients. The ultrasound-guided shamrock LPB technique allows real-time sonographic viewing of the lumbar plexus, various anatomical landmarks, advancement of the needle, and spread of local anaesthetic injectate in most patients. We aimed to compare block procedure outcomes, effectiveness, and safety of the shamrock vs LUT., Methods: Twenty healthy men underwent ultrasound-guided shamrock and LUT LPBs (2% lidocaine–adrenaline 20 ml, with 1 ml diluted contrast added) in a blinded randomized crossover study. The primary outcome was block procedure time. Secondary outcomes were procedural discomfort, number of needle insertions, injectate spread assessed with magnetic resonance imaging, sensorimotor effects, and lidocaine pharmacokinetics., Results: The shamrock LPB procedure was faster than LUT (238 [sd 74] vs 334 [156] s; P=0.009), more comfortable {numeric rating scale 0–10: 3 [interquartile range (IQR) 2–4] vs 4 [3–6]; P=0.03}, and required fewer needle insertions (2 [IQR 1–3] vs 6 [2–12]; P=0.003). Perineural injectate spread seen with magnetic resonance imaging was similar between the groups and consistent with motor and sensory mapping. Zero/20 (0%) and 1/19 (5%) subjects had epidural spread after shamrock and LUT (P=1.00), respectively. The lidocaine pharmacokinetics were similar between the groups., Conclusions: Shamrock was faster, more comfortable, and equally effective compared with LUT., Clinical Trial Registration: NCT02255591, (© The Author 2017. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com)

Fused real-time ultrasound and magnetic resonance imaging (MRI) may be used to improve the accuracy of advanced image guided procedures. However, its use in regional anesthesia is practically nonexistent. In this randomized controlled crossover trial, we aim to explore effectiveness, procedure-related outcomes, injectate spread analyzed by MRI, and safety of ultrasound/MRI fusion versus ultrasound guided Suprasacral Parallel Shift (SSPS) technique for lumbosacral plexus blockade. Twenty-six healthy subjects aged 21-36 years received two SSPS blocks (20 mL 2% lidocaine-epinephrine [1 : 200,000] added 1 mL diluted contrast) guided by ultrasound/MRI fusion versus ultrasound. Number (proportion) of subjects with motor blockade of the femoral and obturator nerves and the lumbosacral trunk was equal (ultrasound/MRI, 23/26 [88%]; ultrasound, 23/26 [88%]; p = 1.00). Median (interquartile range) preparation and procedure times (s) were longer for the ultrasound/MRI fusion guided technique (686 [552-1023] versus 196 [167-228], p < 0.001 and 333 [254-439] versus 216 [176-294], p = 0.001). Both techniques produced perineural spread and corresponding sensory analgesia from L2 to S1. Epidural spread and lidocaine pharmacokinetics were similar. Different compartmentalized patterns of injectate spread were observed. Ultrasound/MRI fusion guided SSPS was equally effective and safe but required prolonged time, compared to ultrasound guided SSPS. This trial is registered with EudraCT (2013-004013-41) and ClinicalTrials.gov (NCT02593370)., Competing Interests: None of the authors have any potential conflicts of interests to declare.

Background: Popliteal sciatic nerve catheters (PSNCs) are associated with a high frequency of displacement. We aimed to estimate the frequency of catheter displacement after 48 h with magnetic resonance imaging (MRI) in patients with PSNCs after major foot and ankle surgery randomized to catheter insertion either with a short-axis in-plane (SAX-IP) approach perpendicular to the nerve or with a short-axis out-of-plane (SAX-OOP) approach parallel to the nerve., Methods: Forty patients were randomly allocated to SAX-IP or SAX-OOP PSNC. Ropivacaine 0.75% 20 ml was injected via the catheter followed by ropivacaine 0.2% 10 ml h(-)1 infusion. Correct primary catheter placement was ensured after initial injection of local anaesthetic via the catheter. Forty-eight hours after insertion, MRI was performed after injection of saline with added contrast (Dotarem) via the catheter. The primary outcome was catheter displacement estimated as the frequency of spread of contrast exclusively outside the paraneurium., Results: All patients had correct primary catheter placement. The frequency of displacement 48 h after insertion of the PSNC was 40% when inserted perpendicular to the nerve vs 10% parallel to the nerve (difference was 30 percentage points, 95% CI: 3-53 percentage points). The relative risk of displacement was four times larger (95% CI: 0.8-10, P<0.028) in the SAX-IP vs the SAX-OOP group. The morphine consumption was 150% greater in the SAX-IP compared with the SAX-OOP group., Conclusion: Popliteal sciatic nerve catheters for major foot and ankle surgery inserted with ultrasound guidance parallel to the sciatic nerve have a significantly lower frequency of displacement compared with those inserted perpendicular to the nerve., Clinical Trial Registration: NCT02200016., (© The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background . Distal arm surgery is widely performed under regional anesthesia with brachial plexus block. The preponderance of evidence for the efficacy relies upon injection of local anesthetic in excess of 30 mL. We aimed to compare three different ultrasound-guided brachial plexus block techniques restricting the total volume to 20 mL. Methods . 120 patients were prospectively randomized to ultrasound-guided brachial plexus block with 20 mL ropivacaine 0.75% at either the supraclavicular, infraclavicular, or axillary level. Multiinjection technique was performed with all three approaches. Primary outcome measure was performance time. Results . Performance time and procedural pain were similar between groups. Needle passes and injection numbers were significantly reduced in the infraclavicular group ( P < 0.01). Nerve visibility was significantly reduced in the axillary group ( P = 0.01). Success-rate was significantly increased in the supraclavicular versus the axillary group ( P < 0.025). Total anesthesia-related time was significantly reduced in the supraclavicular compared to the infraclavicular group ( P < 0.01). Block duration was significantly increased in the infraclavicular group ( P < 0.05). No early adverse effects occurred. Conclusion . Supraclavicular and infraclavicular blocks exhibited favorable characteristics compared to the axillary block. Supraclavicular brachial plexus block with the multiinjection intracluster technique exhibited significantly reduced total anesthesia-related time and higher success rate without any early adverse events., Competing Interests: The authors declare that there are no competing interests regarding the publication of this paper.

Purpose. Transversus abdominis plane (TAP) blocks have been shown to reduce pain and opioid requirements after abdominal surgery. The aim of the present case series was to demonstrate the use of TAP catheter injections of bupivacaine after major abdominal surgery. Methods. Fifteen patients scheduled for open colonic resection surgery were included. After induction of anesthesia, bilateral TAP catheters were placed, and all patients received a bolus dose of 20 mL bupivacaine 2.5 mg/mL with epinephrine 5 μg/mL through each catheter. Additional bolus doses were injected bilaterally 12, 24, and 36 hrs after the first injections. Supplemental pain treatment consisted of paracetamol, ibuprofen, and gabapentin. Intravenous morphine was used as rescue analgesic. Postoperative pain was rated on a numeric rating scale (NRS, 0-10) at regular predefined intervals after surgery, and consumption of intravenous morphine was recorded. Results. The TAP catheters were placed without any technical difficulties. NRS scores were ≤3 at rest and ≤5 during cough at 4, 8, 12, 18, 24, and 36 hrs after surgery. Cumulative consumption of intravenous morphine was 28 (23-48) mg (median, IQR) within the first 48 postoperative hours. Conclusion. TAP catheter bolus injections can be used to prolong analgesia after major abdominal surgery.

Unlabelled: These studies were undertaken to ascertain if there is any association between low birth weight, and low kidney weight, few and/or small glomeruli, in kidneys from a control group and a group of non-insulin-dependent diabetic (NIDDM) patients. The background for this study comes from findings suggesting a correlation between low birth weight and the development of NIDDM and high blood pressure. Furthermore, Brenner has postulated that humans born with a low number of glomeruli, thereby having a low glomerular filtration surface area, have a greater tendency to develop high blood pressure. We examined 79 autopsy kidneys, with known weight from normal and NIDDM patients, which had previously been used for studies of glomerular number and volume. In the archives of the Danish midwives we were able to find birth weight for 26 NIDDM patients and an age- and sex-matched sample of 19 control persons. The kidney weight (g) (, Control: 137 +/- 36; NIDDM: 150 +/- 38; 2p = 0.26), glomerular number (10(3)) (CONTROL: 670 +/- 176; NIDDM: 673 +/- 200; 2p = 0.95), glomerular volume (10(6) micron3) (CONTROL: 6.25 +/- 1.48; NIDDM: 5.71 +/- 1.74; 2p = 0.28) or birth weight (g) (, Control: 3577 +/- 400; NIDDM: 3489 +/- 429; 2p = 0.49) were not different between the groups. There was no significant correlation between birth weight and glomerular number (, Control: 2p = 0.80; r = 0.06 and NIDDM: 2p = 0.10; r = -0.33), glomerular volume (, Control: 2p = 0.43; r = 0.19 and NIDDM: 2p = 0.78; r = 0.06) or kidney weight (, Control: 2p = 0.56; r = 0.14 and NIDDM: 2p = 0.81; r = 0.05). Our results on a limited number of subjects in Denmark do not support the hypothesis that there is any association between low birth weight and low kidney weight or low birth weight and few and/or small glomeruli in NIDDM patients.

The number of glomeruli per kidney in Type 1 (insulin-dependent) and Type 2 (non-insulin-dependent) diabetic patients was estimated by an unbiased stereological method: the fractionator. No significant differences were observed between Type 1 and Type 2 diabetic patients without severe diabetic glomerulopathy and non-diabetic patients. Diabetic patients with proteinuria who were in the early stages of diabetic nephropathy also had a normal number of glomeruli. On the other hand, a subgroup classified as Type 1 diabetic patients with severe diabetic glomerulopathy had significantly less glomeruli compared with Type 1 diabetic patients with mild or no glomerulopathy. A probable explanation is that Type 1 diabetic patients lose glomeruli in relation to the progression of diabetic glomerulopathy. A more theoretical alternative is, however, that development of diabetic glomerulopathy is facilitated by a low number of glomeruli.