Jessica T. Wegener

Value of single-injection or continuous sciatic nerve block in addition to a continuous femoral nerve block in patients undergoing total knee arthroplasty: a prospective, randomized, controlled trial

Background and Objectives: Continuous femoral nerve block in patients undergoing total knee arthroplasty (TKA) improves and shortens postoperative rehabilitation. The primary aim of this study was to investigate whether the addition of sciatic nerve block to continuous femoral nerve block will shorten the time-to-discharge readiness. Methods: Ninety patients undergoing TKA were prospectively randomized to 1 of 3 groups: patient-controlled analgesia via femoral nerve catheter alone (F group) or combined with a single-injection (Fs group) or continuous sciatic nerve block (FCS group) until the second postoperative day. Discharge readiness was defined as the ability to walk and climb stairs independently, average pain on a numerical rating scale at rest lower than 4, and no complications. In addition, knee function, pain, supplemental morphine requirement, local anesthetic consumption, and postoperative nausea and vomiting (PONV) were evaluated. Results: Median time-to-discharge readiness was similar: F group, 4 days (range, 2-16 days); Fs group, 4 days (range, 2-7 days); and FCS group, 4 days (range, 2-9 days; P = 0.631). No significant differences were found regarding knee function, local anesthetic consumption, or postoperative nausea and vomiting. During the day of surgery, pain was moderate to severe in the F group, whereas Fs and FCS groups experienced minimal pain (P < 0.01). Patients in the F group required significantly more supplemental morphine on the day of surgery and the first postoperative day. Until the second postoperative day, pain was significantly less in the FCS group (P < 0.01). Conclusions: A single-injection or continuous sciatic nerve block in addition to a femoral nerve block did not influence time-to-discharge readiness. A single-injection sciatic nerve block can reduce severe pain on the day of the surgery, whereas a continuous sciatic nerve block reduces moderate pain during mobilization on the first 2 postoperative days.

Effect of Local Anesthetic Volume (15 vs 40 mL) on the Duration of Ultrasound-Guided Single Shot Axillary Brachial Plexus Block A Prospective Randomized, Observer-Blinded Trial

Background and Objectives One of the advantages of ultrasound-guided peripheral nerve block is that visualization of local anesthetic spread allows for a reduction in dose. However, little is known about the effect of dose reduction on sensory and motor block duration. The purpose of the present study was to compare the duration of sensory and motor axillary brachial plexus block (ABPB) with 15 or 40 mL mepivacaine 1.5%. Methods Thirty patients were randomly allocated to receive ultrasound-guided ABPB with either 15 (group 15 mL, n = 15) or 40 mL (group 40 mL, n = 15) mepivacaine 1.5%. Onset, efficacy, and duration of sensory and motor block were compared. Results Two patients in group 15 mL needed an additional rescue block before surgery and were excluded from subsequent analysis. The overall median duration of sensory and motor block was significantly shorter in group 15 mL (225 [148–265] mins vs 271 [210–401] mins and 217 [144–250] mins vs 269 [210–401] mins, respectively; P < 0.01). Duration of sensory and motor block of individual nerves was significantly shorter in group 15 mL (20%–40% reduction for sensory and 18%–37% for motor block). Time to first request of postoperative analgesia was also significantly reduced in group 15 mL (163 [SD, 39] vs 235 [SD, 59] mins, respectively, P < 0.05). There were no differences in the other block characteristics. Conclusions In ABPB with mepivacaine 1.5%, reducing the dose from 40 mL to 15 mL (62.5%) shortens the overall duration of sensory and motor block by approximately 17% to 19%, reduces sensory and motor block duration of individual nerves by 18% to 40%, and decreases the time to first request of postoperative analgesia by approximately 30%.

Long-term pain and functional disability after total knee arthroplasty with and without single-injection or continuous sciatic nerve block in addition to continuous femoral nerve block: a prospective, 1-year follow-up of a randomized controlled trial.

Background and Objectives This is a follow-up to determine long-term outcomes after total knee arthroplasty (TKA) in patients enrolled in a previous randomized trial that found reduced postoperative pain after addition of sciatic nerve block to continuous femoral nerve block for TKA. Methods Physical function after TKA was evaluated at 3 and 12 months in patients (n = 89) receiving continuous femoral nerve block alone (group F), combined with a single-injection (group Fs) or continuous sciatic nerve block (group FCS) after TKA, until the second postoperative day. Physical function, stiffness, and pain were measured by using Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Oxford Knee Score 12-item knee questionnaires, and visual analog scale at rest and during mobilization before TKA and 3 and 12 months afterward. Post hoc, a median split on poor functioning (WOMAC) was analyzed. Results Western Ontario and McMaster Universities Osteoarthritis Index, Oxford Knee Score 12-item knee, and visual analog scale scores improved significantly in all patients, without any differences among groups. Median (range) WOMAC at 3 months were in group F, 83 (20–97); group Fs, 72 (25–99); and group, FCS 76 (28–100) and at 12 months 87 (35–98), 77 (43–100), and 89 (35–100), respectively. Conclusions No differences were detected in the secondary outcomes we examined. Thus, improved postoperative outcome did not translate into improved functional outcome or long-term pain.

Value of an electronic tutorial for image interpretation in ultrasound-guided regional anesthesia.

Background and Objectives Use of ultrasound-guided regional anesthesia (UGRA) requires considerable training. An embedded electronic tutorial as an element of an ultrasound machine may help to identify sonoanatomy for novices. Therefore, we investigated whether an electronic tutorial could improve accuracy or speed of performance in identifying anatomical structures. Methods Thirty-five novices in UGRA participated in a workshop on brachial plexus sonoanatomy. Following a lecture and training in handling of ultrasound machines and hand-eye coordination, participants were randomized in either group S, using a standard ultrasound machine, or group T, using the same type of machine with an onboard electronic tutorial. Each participant had to identify 27 anatomical structures from the brachial plexus of a volunteer. A correctly identified structure scored 1 point. An experienced observer noted scores and time required. Scores ± SD (in %) and times ± SD (in seconds) were compared between groups by analyses of independent-samples t test and analysis of variance. Influence of anesthesia experience was determined by multivariate analyses. Results Group T scored significantly higher (16.8 ± 3.6 [62%] vs 13.4 ± 4.4 [50%], P = 0.018), whereas time required was longer (1053 ± 244 vs 740 ± 244 seconds, P = 0.001). Multivariate analysis revealed that experience had no influence on scores or time required. Examination of structures took more time in the beginning than at the end in group T. Conclusions An electronic tutorial can help novices in UGRA identify anatomical structures. A significant increase in correct identifications was gained at the expense of significantly longer time required for this process. Increased time required may partly be related to unfamiliarity with the tutorial.

Comparison of percutaneous electrical nerve stimulation and ultrasound imaging for nerve localization

BACKGROUND Percutaneous nerve stimulation (PNS) is a non-invasive technique to localize superficial nerves before performing peripheral nerve blocks, but its precision has never been evaluated by high-resolution ultrasound. This study compared stimulating points at the skin with the position of nerve structures determined by ultrasound. Correlations between distances and percutaneous stimulation thresholds were determined. METHODS PNS was performed in 20 healthy volunteers systematically with a stimulating pen at the neck after attaching a transparent film with 49 (7×7) perforations. Stimulation thresholds were measured and impedance was controlled. Thereafter, an independent observer measured the depth (D) of the most superficial nerve structure with ultrasound. Distances between stimulating points and the most superficial nerve structure (S) were measured. Correlations between associated stimulating thresholds and distances D and S were calculated. RESULTS The stimulating point with the lowest current was identical to the point closest to the nerve in only 10% of measurements. Median S was 12.6 (3.4-32.0) mm and D 7.6 (0.3-28.6) mm. Distances did not correlate with percutaneous stimulation thresholds. CONCLUSION PNS with a stimulating pen is not a reliable technique for nerve localization in the brachial plexus as verified by high-resolution ultrasound.

Anesthesia and Analgesia Practice Pathway Options for Total Knee Arthroplasty: An Evidence-Based Review by the American and European Societies of Regional Anesthesia and Pain Medicine

Abstract In 2014, the American Society of Regional Anesthesia and Pain Medicine in collaboration with the European Society of Regional Anaesthesia and Pain Therapy convened a group of experts to compare pathways for anesthetic and analgesic management for patients undergoing total knee arthroplasty in North America and Europe and to develop a practice pathway. This review is intended to be an analysis of the current literature to assist individuals and institutions in designing a pathway for total knee arthroplasty that is based on existing evidence and expert recommendation and may be customized according to individual settings.

Low-dose dexamethasone during arthroplasty

Dexamethasone is commonly applied during arthroplasty to control post-operative nausea and vomiting (PONV). However, conflicting views of orthopaedic surgeons and anaesthesiologists regarding the use of dexamethasone raise questions about risks of impaired wound healing and surgical site infections (SSI). The aim of this systematic review is to determine the level of evidence for the safety of a peri-operative single low dose of dexamethasone in hip and knee arthroplasty. We systematically reviewed literature in PubMed, EMBASE and Cochrane databases and cited references in articles found in the initial search from 1980 to 2013 based on predefined inclusion criteria. The review was completed with a ‘pro’ and ‘con’ discussion. After identifying 11 studies out of 104, only eight studies met the inclusion criteria. In total, 1335 patients were studied without any incidence of SSI. Causes of SSI are multifactorial. Therefore, 27 205 patients would be required (power = 90%, alpha = 0.05) to provide substantiated conclusions on safety of a single low dose of dexamethasone. Positively, many studies demonstrated showed convincing effects of low-dose dexamethasone on prevention of PONV and dose-dependent effects on post-operative pain and quality of recovery. Dexamethasone induces hyperglycaemia, but none of the studies demonstrated a concomitant SSI. Conversely, animal studies showed that high dose dexamethasone inhibits wound healing. A team approach of anaesthesiologists and orthopaedic surgeons is mandatory in order to balance the risk–benefit ratio of peri-operatively applied steroids for individual arthroplasty patients. We did not find evidence that a single low dose of dexamethasone contributes to SSI or wound healing impairment from the current studies. Cite this article: Wegener JT, Kraal T, Stevens MF, Hollman MW, Kerkhoffs GMMJ, Haverkamp D. Low-dose dexamethasone during arthroplasty: what do we know about the risks? EFORT Open Rev 2016;1:303-309. DOI: 10.1302/2058-5241.1.000039.

Teaching concepts in ultrasound-guided regional anesthesia

Purpose of review Ultrasound-guided regional anesthesia is a challenging, complex skill and requires competence in teaching. The aim of this study was to review current literature on identification of education and learning of ultrasound-guided regional anesthesia and to summarize recent findings on teaching concepts. Recent findings Several teaching programs have been described and implemented into daily routine. Factors relevant to current practice are the knowledge of sonoanatomy, the acquisition of manual skills, the teaching ability, and the feedback given to the trainee. Simulation is a rapidly growing field and is supported by the development of phantoms. Needle visualization is one of the core competencies that is necessary for successful ultrasound-guided procedures and could be supported by technical developments in the future to improve teaching concepts. Summary Although a lot of key questions cannot be answered by the latest study results, some interesting findings were able to improve existing education programs. These results should be tailored to the individual need of a trainee, and the effects of improved training programs on patient safety and quality of care have to be investigated. The see one, do one, teach one approach is obsolete and should be abandoned.

Influence of arm position on ultrasound visibility of the axillary brachial plexus

BACKGROUND Contemporary axillary brachial plexus block is performed by separate injections targeting radial, median, ulnar and musculocutaneous nerve. These nerves are arranged around the axillary artery, making ultrasound visualisation sometimes challenging. In particular, the radial nerve can be difficult to localise deep to the artery. OBJECTIVES The primary aim of this study was to investigate which arm position optimises the visibility of the radial nerve. Secondary aims were the visibility and position of the other nerves during varying arm positions. DESIGN A prospective observational study. SETTING University teaching hospital, November 2012. PARTICIPANTS Twenty volunteers, recruited by an advertisement on the Departments bulletin board. Inclusion criterion age more than 18 years. Exclusion criteria: refusal of ultrasound examination, restricted shoulder movement, local infection, BMI greater than 30 kg m–2. INTERVENTION One anaesthesiologist performed bilateral ultrasound examinations of the axillary brachial plexus on 20 volunteers. Each arm was placed in different positions [shoulder (S) 90° or 180° abduction, elbow (E) 0° or 90° extension] and scans were performed proximally in the axilla, and additionally 5 cm distally to this point [proximal (P) vs. distal (D)], resulting in eight different scans stored for off-line analysis performed by two blinded anaesthesiologists. MAIN OUTCOME MEASURES For radial, median, ulnar and musculocutaneous nerve, visibility was assessed on a six-point visibility scale. Distances and angles of the nerves relative to the axillary artery and distances relative to the skin were measured. RESULTS No significant differences between arm positions were found in the visibility score of radial (P = 0.359) and musculocutaneous nerves (P = 0.073). Visibility of the median nerve was improved in positions S90°/E0°/D and S180°/E0°/P (P = 0.02). The ulnar nerve was more visible in position S180°/E 0°/P and D (P = 0.007). The greatest distance between artery and radial nerve was 7.4 ± 4.7 mm at an angle of 120 ± 14° in position S180°/E 0°/D. CONCLUSION The visibility of the radial nerve was not improved by varying positions of the arm. S180°/E0° provided the best overall visibility and accessibility of nerves. TRIAL REGISTRATION https://www.toetsingonline.nl/to/ccmo_search.nsf/Searchform?OpenForm Identifier: NL42116.018.12.