Standardizing nomenclature in regional anesthesia: an ASRA-ESRA Delphi consensus study of upper and lower limb nerve blocks

BACKGROUND

Inconsistent nomenclature and anatomical descriptions of regional anesthetic techniques hinder scientific communication and engender confusion; this in turn has implications for research, education and clinical implementation of regional anesthesia. Having produced standardized nomenclature for abdominal wall, paraspinal and chest wall regional anesthetic techniques, we aimed to similarly do so for upper and lower limb peripheral nerve blocks.

METHODS

We performed a three-round Delphi international consensus study to generate standardized names and anatomical descriptions of upper and lower limb regional anesthetic techniques. A long list of names and anatomical description of blocks of upper and lower extremities was produced by the members of the steering committee. Subsequently, two rounds of anonymized voting and commenting were followed by a third virtual round table to secure consensus for items that remained outstanding after the first and second rounds. As with previous methodology, strong consensus was defined as ≥75% agreement and weak consensus as 50%-74% agreement.

RESULTS

A total of 94, 91 and 65 collaborators participated in the first, second and third rounds, respectively. We achieved strong consensus for 38 names and 33 anatomical descriptions, and weak consensus for five anatomical descriptions. We agreed on a template for naming peripheral nerve blocks based on the name of the nerve and the anatomical location of the blockade and identified several areas for future research.

CONCLUSIONS

We achieved consensus on nomenclature and anatomical descriptions of regional anesthetic techniques for upper and lower limb nerve blocks, and recommend using this framework in clinical and academic practice. This should improve research, teaching and learning of regional anesthesia to eventually improve patient care.

Standardizing nomenclature in regional anesthesia: an ASRA-ESRA Delphi consensus study of abdominal wall, paraspinal, and chest wall blocks

BACKGROUND

There is heterogeneity in the names and anatomical descriptions of regional anesthetic techniques. This may have adverse consequences on education, research, and implementation into clinical practice. We aimed to produce standardized nomenclature for abdominal wall, paraspinal, and chest wall regional anesthetic techniques.

METHODS

We conducted an international consensus study involving experts using a three-round Delphi method to produce a list of names and corresponding descriptions of anatomical targets. After long-list formulation by a Steering Committee, the first and second rounds involved anonymous electronic voting and commenting, with the third round involving a virtual round table discussion aiming to achieve consensus on items that had yet to achieve it. Novel names were presented where required for anatomical clarity and harmonization. Strong consensus was defined as ≥75% agreement and weak consensus as 50% to 74% agreement.

RESULTS

Sixty expert Collaborators participated in this study. After three rounds and clarification, harmonization, and introduction of novel nomenclature, strong consensus was achieved for the names of 16 block names and weak consensus for four names. For anatomical descriptions, strong consensus was achieved for 19 blocks and weak consensus was achieved for one approach. Several areas requiring further research were identified.

CONCLUSIONS

Harmonization and standardization of nomenclature may improve education, research, and ultimately patient care. We present the first international consensus on nomenclature and anatomical descriptions of blocks of the abdominal wall, chest wall, and paraspinal blocks. We recommend using the consensus results in academic and clinical practice.

Is Supraclavicular Block as Good as Interscalene Block for Acute Pain Control Following Shoulder Surgery? A Systematic Review and Meta-analysis

BACKGROUND

Interscalene block (ISB) is the acute pain management technique of choice for shoulder surgery, but its undesirable respiratory side effects have prompted seeking alternatives. Supraclavicular block (SCB) is proposed as an ISB alternative, but evidence of comparative analgesic and respiratory-sparing effects is inconsistent. We compared the analgesic and respiratory effects of SCB and ISB for shoulder surgery.

METHODS

Trials comparing ISB to SCB for shoulder surgery were sought. We decided a priori that SCB would be an acceptable alternative if it were noninferior for (1) postoperative 24-hour cumulative oral morphine equivalent consumption (primary outcome, noninferiority margin Δ = -25 mg) and (2) postoperative pain (secondary outcome, noninferiority margin Δ = 4.0 cm·hour); and superior for (3) postblock respiratory dysfunction (primary outcome). Opioid-related side effects and block-related complications were also evaluated.

RESULTS

Fifteen studies (1065 patients) were analyzed. In single-injection blocks, SCB was noninferior to ISB for 24-hour morphine consumption (mean difference for SCB-ISB, MD [95% confidence interval {CI}] = -3.11 mg [-9.42 to 3.19], Δ = -25 mg); it was also noninferior for 24-hour pain scores (MD = 0.78 cm·hour [0.07-1.49], Δ = 4.0 cm·hour); and decreased the odds of respiratory dysfunction (odds ratio [OR] [95% CI] = 0.08 [0.01-0.68]). Similarly, in continuous blocks, SCB was noninferior to ISB for 24-hour morphine consumption (MD = 0.46 mg [-6.08 to 5.15], Δ = -25 mg), and decreased the odds of respiratory dysfunction (OR = 0.22 [0.08-0.57]). SCB also decreased odds of minor block-related complications (OR = 0.36 [0.20-0.68] and OR = 0.25 [0.15-0.41] for single-injection and continuous blocks, respectively). Consequently, the null joint-hypothesis was rejected, and SCB can be considered an acceptable alternative to ISB.

CONCLUSIONS

For acute pain control following shoulder surgery, high-quality evidence indicates that SCB can be used as an effective ISB alternative. SCB is noninferior for postoperative opioid consumption and acute pain, and it reduces the odds of postblock respiratory dysfunction.

Analgesic benefits and clinical role of the posterior suprascapular nerve block in shoulder surgery: a systematic review, meta-analysis and trial sequential analysis

The posterior suprascapular nerve block has been proposed as an analgesic alternative for shoulder surgery based on the publication of several comparisons with interscalene block that failed to detect differences in analgesic outcomes. However, quantification of the absolute treatment effect of suprascapular nerve block on its own, in comparison with no block (control), to corroborate the aforementioned conclusions has been lacking. This study examines the absolute analgesic efficacy of suprascapular nerve block compared with control for shoulder surgery. We systematically sought electronic databases for studies comparing suprascapular nerve block with control. The primary outcomes included postoperative 24-h cumulative oral morphine consumption and the difference in area under the curve for 24-h pooled pain scores. Secondary outcomes included the incidence of opioid-related side-effects (postoperative nausea and vomiting) and patient satisfaction. Data were pooled using random-effects modelling. Ten studies (700 patients) were analysed; all studies examined landmark-guided posterior suprascapular nerve block performed in the suprascapular fossa. Suprascapular nerve block was statistically but not clinically superior to control for postoperative 24-h cumulative oral morphine consumption, with a weighted mean difference (99%CI) of 11.41 mg (-21.28 to -1.54; p = 0.003). Suprascapular nerve block was also statistically but not clinically superior to control for area under the curve of pain scores, with a mean difference of 1.01 cm.h. Nonetheless, suprascapular nerve block reduced the odds of postoperative nausea and vomiting and improved patient satisfaction. This review suggests that the landmark-guided posterior suprascapular nerve block does not provide clinically important analgesic benefits for shoulder surgery. Investigation of other interscalene block alternatives is warranted.

Midpoint transverse process to pleura catheter placement for postoperative analgesia following video-assisted thoracoscopic surgery

The ultrasound-guided midpoint transverse process to pleura block has been described as an alternative end-point for thoracic paravertebral blockade. Although originally described as a single-level block, midpoint transverse process to pleura blockade may cover more than one level when larger volumes of injectate are used. Moreover, a continuous catheter midpoint transverse process to pleura blockade technique was previously thought to be unfeasible. We report three cases where a midpoint transverse process to pleura continuous catheter technique was successfully used for postoperative analgesia following video-assisted thoracoscopic surgery.

Mid-point transverse process to pleura block for surgical anaesthesia

The use of ultrasound in regional anaesthesia has expanded our understanding of regional anaesthesia techniques and allowed for the development of novel strategies to achieve blockade of the trunk. Several alternatives to paravertebral block have recently been proposed, but none of these new techniques have yet been shown to provide surgical anaesthesia equivalent to a paravertebral block. This case report describes the successful use of the mid-point transverse process to pleura (MTP) block as the sole anaesthetic technique for a patient undergoing breast surgery.

Pain management within an enhanced recovery program after thoracic surgery

Evidence for ERAS within thoracic surgery (ERATS) is building. The key to enabling early recovery and ambulation is ensuring that postoperative pain is well controlled. Surgery on the chest is considered to be one of the most painful of surgical procedures for both open and minimally invasive surgery (MIS) approaches. Increasing use of MIS and improved perioperative care pathways has resulted in shorter length of stay (LOS), requiring patients to achieve optimal pain control earlier and meet discharge criteria sooner, sometimes on the same day as surgery. This requires optimizing pain control earlier in the postoperative recovery phase in order to enable ambulation and a better recovery profile, as well as to minimize the risk for development of chronic persistent postoperative pain (CPPP). This review will focus on the options for pain management protocols within an ERAS program for thoracic surgery patients (ERATS).

Single-Dose Haloperidol for the Prophylaxis of Postoperative Nausea and Vomiting After Intrathecal Morphine

Postoperative nausea and vomiting (PONV) occurs frequently with the use of intrathecal morphine. We studied the ability of a single, small dose of the inexpensive, long-acting, dopamine receptor-blocking drug, haloperidol, to prevent PONV after spinal anesthesia using local anesthetic with morphine 0.3 mg. One-hundred-eight adult patients undergoing elective lower limb orthopedic or endoscopic urologic procedures under spinal anesthesia were randomized to receive IM haloperidol 1 mg (H1), haloperidol 2 mg (H2), or placebo (P) after an intrathecal injection. Patients were assessed for 24 h after surgery, with treatment failure being defined as nausea >1 on a 10-cm visual analog scale or any vomiting or request for rescue antiemetic. Most treatment failures occurred during the first 12 h (60% overall), and haloperidol led to a dose-dependent decrease in PONV (first 12 h: 76% P, 56% H1, and 50% H2; P = 0.012). A history of PONV was strongly associated with PONV in the current study, regardless of treatment group. There were no dystonic reactions noted to either dose of haloperidol. We conclude that haloperidol reduces the incidence of PONV after intrathecal morphine, although this incidence remains a significant problem even with treatment.

IMPLICATIONS

In this randomized, double-blinded, placebo-controlled trial, a single, small IM dose of haloperidol 1 mg or 2 mg reduced the incidence of postoperative nausea and vomiting after spinal anesthesia with local anesthetic and intrathecal morphine.