Catherine Vandepitte

The minimum effective anesthetic volume of 0.75% ropivacaine in ultrasound-guided interscalene brachial plexus block.

BACKGROUND:The use of ultrasound to monitor needle placement and spread of local anesthetics (LA) has allowed reductions in the volume of LA required to anesthetize peripheral nerves. In the current study we investigated the minimal volume necessary to accomplish surgical anesthesia with interscalene brachial plexus block. METHODS:Twenty ASA physical status I–III patients, ages 18 to 75 years and scheduled for shoulder surgery under interscalene brachial plexus block, were enrolled. Using a previously validated step-up/step-down method, we determined the injection volume of 0.75% ropivacaine used for consecutive patients by the outcome of the preceding block. The starting volume was 15 mL (3 injections of 5 mL per each trunk); in the case of block failure, the volume was increased by 1 mL, whereas after successful block, the volume was reduced by 1 mL. The study was stopped upon achieving the secondary stopping rule of 10 consecutive successful interscalane blocks using 5 mL of ropivacaine 0.75%. Successful surgical anesthesia with the brachial plexus block was defined as presence of adequate motor block (motor score of ⩽2 on 0 to 4 scale), absent sensation to cold and pinprick sensation within 30 minutes of injection, and absence of the need for general anesthesia for completion of surgery. Duration of sensory blockade was assessed by asking the patient to record the time of first pain sensation. RESULTS:Under our study conditions, successful surgical anesthesia for arthroscopic shoulder surgery can be achieved with 5 mL of 0.75% ropivacaine, or approximately 1.7 mL per each of the 3 trunks of the brachial plexus (superior, middle, and inferior). The study was stopped after 10 consecutive successful blocks with 5 mL of LA (100%, 95% confidence interval [CI]: 74.1%–100%). For the group as a whole, the median (range) sensory block onset time was 5 (5–20) minutes, the median (range) motor block for the biceps was 7.5 (5–15) minutes, and for abduction 10 (5–15) minutes. The median (range) block duration was 9.9 (5–19) hours, and the mean (SD) block performance time was 8.0 ± 3.2 minutes. Mean duration of analgesia was 9.9 ± 3.7 hours. Duration of analgesia was not associated with volume of LA (r = 0.05, P = 0.83). CONCLUSIONS:All patients in our study had successful surgical blocks with 5 mL of LA. However, the lower limit of the CI (calculated on the assumption of a single failure) does include the possibility of a 25% failure rate; thus studies using similar stopping rules for doses higher than 5 mL are nonetheless warranted.

Fascia lliaca block for analgesia after hip arthroplasty: a randomized double-blind, placebo-controlled trial.

Background and Objectives Fascia iliaca block (FIB) is often used to treat pain after total hip arthroplasty (THA), despite a lack of randomized trials to evaluate its efficacy for this indication. The objective of this study was to assess the analgesic benefit of FIB after THA. Our primary hypothesis was administration of FIB decreases the intensity of postoperative pain (numeric rating scale [NRS-11] score) compared with sham block (SB) in patients after THA. Methods After institutional review board approval and informed consent, 32 eligible patients having THA were recruited. In the postoperative care unit, although all patients received intravenous morphine sulfate patient-controlled analgesia, patients reporting pain of 3 or greater on the NRS-11 scale were randomized to receive ultrasound-guided fascia iliaca (30 mL 0.5% ropivacaine) or SB (30 mL 0.9% NaCl) using identical technique, below fascia iliaca. The primary outcome was pain intensity (NRS-11) after FIB. Results Thirty-two patients (16 in each group) completed the study; all patients received an FIB. There was no difference in pain intensity (NRS-11 = 5.0 ± 0.6 vs 4.7 ± 0.6, respectively) after FIB versus SB or in opioid consumption (8.97 ± 1.6 vs 5.7 ± 1.6 mg morphine, respectively) between the groups at 1 hour. The morphine consumption after 24 hours was similar in both groups (49.0 ± 29.9 vs 50.4 ± 34.5 mg, P = 0.88, respectively). Conclusions The evidence in these data suggests that the difference in average pain intensity after FIB versus SB was not significant (95% confidence interval, −2.2–1.4 NRS units).

Feasibility and analgesic efficacy of the transversus abdominis plane block after single-port laparoscopy in patients having bariatric surgery.

Purpose The transversus abdominis plane (TAP) block is a technique increasingly used for analgesia after surgery on the anterior abdominal wall. We undertook this study to determine the feasibility and analgesic efficacy of ultrasound-guided TAP blocks in morbidly obese patients. We describe the dermatomal spread of local anesthetic in TAP blocks administered, and test the hypothesis that TAP blocks decrease visual analog scale (VAS) scores. Patients and methods After ethics committee approval and informed consent, 35 patients with body mass index >35 undergoing single-port sleeve gastrectomy (SPSG) were enrolled. All patients received balanced general anesthesia, followed by intravenous patient-controlled analgesia (IV-PCA; hydromorphone) postoperatively; all reported VAS >3 upon arrival to the recovery room. From the cohort of 35 patients having single-port laparoscopy (SPL), a sealed envelope method was used to randomly select ten patients to the TAP group and 25 patients to the control group. The ten patients in the TAP group received ultrasound-guided TAP blocks with 30 mL of 0.2% Ropivacaine injected bilaterally. The dermatomal distribution of the sensory block (by pinprick test) was recorded. VAS scores for the first 24 hours after surgery and opioid use were compared between the IV-PCA+TAP block and IV-PCA only groups. Results Sensory block ranged from T5–L1. Mean VAS pain scores decreased from 8 ± 2 to 4 ± 3 (P=0.04) within 30 minutes of TAP block administration. Compared with patients given IV-PCA only, significantly fewer patients who received TAP block had moderate or severe pain (VAS 4–10) after block administration at 6 hours and 12 hours post-surgery. However, cumulative consumption of hydromorphone at 24 hours after SPSG surgery was similar for both groups. Conclusion Ultrasound-guided TAP blocks in morbidly obese patients are feasible and result in satisfactory analgesia following SPSG in the immediate postoperative period.

Effective Volume of Ropivacaine 0.75% Through a Catheter Required for Interscalene Brachial Plexus Blockade

Background:Ultrasound guidance during peripheral nerve blocks has allowed for reduction in dose and volume of local anesthetic required to accomplish successful blockade using multiple injections through a needle. The authors undertook this study to determine the minimal effective volume required to accomplish successful interscalene brachial plexus block (ISB) through the catheter. Methods:After obtaining institutional ethics committee approval and written informed consent, patients aged 18–75 yr and scheduled for arthroscopic shoulder surgery under ISB were enrolled. All patients using a step-up/step-down method and the starting dose of 15 ml of 0.75% ropivacaine received an ultrasound-guided ISB catheter. The injection volume was increased or decreased by 1 ml in case of block failure or block success, respectively. Results:The authors found that the proportion of patients with successful blockade increased sharply from approximately 57% at 6 ml to 100% by 7 ml, indicating that a small increase in volume of ropivacaine 0.75% markedly affects the success rate. A total of 12 ISB with injection volume less than 7 ml resulted in successful anesthesia within 30 min, yielding an ED95 of 7 ml (95% CI 6.8–7.2) ropivacaine 0.75%. For the group as a whole, the median (min–max) sensory block onset time was 5 (5–20) min, the median (min–max) motor blocks for the biceps and the deltoid muscles were 7.5 (5–15) min and 10 (5–15) min, respectively. The median (min–max) block duration was 8.9 (3–15) h. Conclusions:An injection of a minimum of 7 ml of ropivacaine 0.75% through the catheter is required for success rate and timely onset of surgical anesthesia with ISB.

Ultrasound-guided Continuous Thoracic Paravertebral Block for Outpatient Acute Pain Management of Multilevel Unilateral Rib Fractures

A 61-year-old man with multiple unilateral rib fractures (T3-T8) gained the ability to breathe deeply and to ambulate after ultrasound-guided continuous thoracic paravertebral block and was discharged home after being observed for 15 hours after the block. The ultrasound guidance was helpful in determining the site of rib fractures and the optimal level for catheter placement. This report also discusses the management of analgesia using continuous paravertebral block in an outpatient with trauma.

Addition of Liposome Bupivacaine to Bupivacaine HCl Versus Bupivacaine HCl Alone for Interscalene Brachial Plexus Block in Patients Having Major Shoulder Surgery

Background and Objectives We examined whether liposome bupivacaine (Exparel) given in the interscalene brachial plexus block lowers pain in the setting of multimodal postoperative pain management for major shoulder surgery. Methods Fifty-two adult patients were randomized to receive either 5 mL of 0.25% bupivacaine HCl immediately followed by 10 mL of liposome bupivacaine 133 mg (n = 26) or 15 mL of 0.25% standard bupivacaine alone (n = 26) in interscalene brachial plexus block. The primary outcome (worst pain in the first postoperative week) was assessed by the Modified Brief Pain Inventory short form. Secondary outcomes were overall satisfaction with analgesia (OBAS), functionality of the surgical arm, sleep duration, time to first opioid (tramadol) request and opioid consumption (mEq), sensory-motor block characteristics, and the occurrence of adverse effects. Results Worst pain was lower in patients given liposome bupivacaine added to standard bupivacaine than in patients given standard bupivacaine alone (generalized estimating equation [GEE] estimated marginal mean values, 3.6 ± 0.3 vs 5.3 ± 0.4 points on the Numeric Rating Scale, respectively, although the effect was modest, 1.6 ± 0.5; 95% confidence interval, 0.8–2.5). Total OBAS scores indicated greater satisfaction (GEE estimated marginal mean values, 1.8 ± 0.3 vs 3.3 ± 0.4 on total OBAS, respectively, with modest effect, difference, 1.4 ± 0.5; 95% confidence interval, 0.5–2.4). There were no differences in any of the other secondary outcomes. Conclusions Liposome bupivacaine added to standard bupivacaine may lower pain and enhance patients satisfaction in the first postoperative week even in the setting of multimodal analgesia for major shoulder surgery. This study was registered with clinicaltrials.gov (NCT02554357) on July 11, 2015, by Principal Investigator Catherine Vandepitte, MD.

Standard approaches for upper extremity nerve blocks with an emphasis on outpatient surgery.

Purpose of review Currently, no standards exist with regard to the techniques and administration of ultrasound-guided peripheral nerve blocks. Consequently, the techniques and teaching substantially vary among practitioners and institutions. The purpose of this review is to propose a set of standard US-guided techniques for upper extremity nerve blocks. Recent findings On the basis of the synthesis of information in available literature and the consensus of an internationally recognized collaborative panel of regional anaesthesia experts, the review recommends a standardized approach to common upper extremity nerve blocks using ultrasound guidance. Summary A set of structured recommendations and approaches are suggested to help standardize clinical practice and teaching of ultrasound-guided upper extremity nerve blocks. Additional emphasis is placed on the discussion of nerve blocks in outpatient surgery.

Aberrant vein within common connective tissue sheath of the sciatic nerve at the popliteal fossa.

To the Editor: We thank Dr Egeler and colleagues for their interest in our study and for their thoughtful comments regarding the nerve supply to the knee. We agree that the deposition of local anesthetic within the adductor canal (AC) is likely to result in blockade of the nerve to vastus medialis, since it has been demonstrated to reliably lie within this space. However, we were not able to demonstrate

Dislocation of a femur fracture after femoral nerve block.

Objective Femoral nerve block (FNB) is increasingly used as an analgesic modality in patients with femoral fracture both in the emergency department and preoperatively. We describe an occurrence of unexpected dislocation of the fracture after FNB. Case Report An FNB was administered to treat pain in a 48-year-old patient with metastatic breast carcinoma and multiple bone metastases. A diagnostic FNB with 20 mL of 0.25% levobupivacaine resulted in analgesia but also in unexpected gross deformity in the proximal right femur. An x-ray revealed a pathologic fracture of the proximal third femur diaphysis, with reduction and angulation of fragments, necessitating urgent surgery. Conclusions Femoral nerve block confers effective analgesia for femur fracture. However, relaxation of the quadriceps femoris muscle may destabilize the fracture because of an unopposed tone of the hamstrings and/or thigh adductors.

Evoked motor response of the sartorius muscle and femoral nerve blockade.

quality. According to the documentation of the anesthetic spread by ultrasound, all injections seemingly occurred at the point at which the branch(es) to the sartorius and femoral nerves were contiguous. Of note, the Anns et al. study excluded patients with difficult anatomy (obesity). However, 2 factors make it difficult to predict whether a sartorius motor response occurs where the branches to sartorius and femoral nerve are contiguous: the anatomical variability in the departure of the (often multiple) branches to the sartorius muscle, and the unpredictable relationship between surface anatomy and underlying neurovascular anatomy in the obese population (Fig. 1). An injection of local anesthetic after stimulation of a branch to the sartorius at a sufficient distance from the femoral nerve may preclude successful femoral nerve blockade (Fig. 1). Therefore, when using a nerve stimulator alone to guide femoral nerve block, obtaining quadriceps motor response should result in a more consistent blockade in different practice/skill settings and/or in patients with less than ideal anatomy.