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.

Comparison of equipotent doses of intrathecal hyperbaric prilocaine 2% and hyperbaric bupivacaine 0.5% for elective caesarean section: A prospective, randomised, controlled, two-centre clinical trial

BACKGROUND

Elective caesarean section is performed mainly under spinal anaesthesia using hyperbaric bupivacaine combined with opioids. Despite rapid onset, good quality anaesthesia, bupivacaine provides a long duration of motor block and is related to maternal hypotension. Current policies appeal for implementation of enhanced recovery procedures after caesarean section. Hyperbaric prilocaine is an intermediate-acting local anaesthetic known for its efficacy in ambulatory surgery. Evidence on the clinical relevance of intrathecal prilocaine use for caesarean section is currently lacking.

OBJECTIVES

We aimed to investigate whether hyperbaric prilocaine would offer a shorter motor block and recovery than bupivacaine, when comparing equipotent doses. We also assessed the characteristics of sensory block, maternal haemodynamics and side effects for both mother and newborn.

DESIGN

Prospective, randomised, double-blind, controlled, two-centre, clinical trial.

SETTING

One university teaching hospital and one general teaching hospital in Brussels, Belgium.

PATIENTS

American Society of Anesthesiologists' physical status 2 parturients (n = 40) undergoing caesarean section under spinal anaesthesia.

INTERVENTIONS

Patients were randomly assigned to receive spinal anaesthesia using hyperbaric prilocaine 50 mg or hyperbaric bupivacaine 10 mg, both given with sufentanil 2.5 μg and morphine 100 μg. An epidural catheter was introduced as a backup in case of failure.

MAIN OUTCOMES

The primary outcome was the motor block regression (modified Bromage scale 1 to 6). Secondary outcomes included sensory block characteristics, first unassisted ambulation, maternal side effects, newborns' parameters and overall satisfaction.

RESULTS

Median [IQR] motor block was significantly shorter in the hyperbaric prilocaine group (110 [104 to 150] min versus 175 [135 to 189] min, P = 0.001). First unassisted ambulation was achieved earlier after prilocaine (204.5 [177 to 246.5] min versus 314 [209.25 to 400] min, P = 0.007), and the incidence of maternal hypotension was significantly higher with bupivacaine (P = 0.033). No supplementary epidural analgesia was needed.

CONCLUSION

Prilocaine provides shorter motor block, faster recovery and better haemodynamic stability than bupivacaine while offering equivalent surgical anaesthesia.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT02973048, EudraCT: 2016-003010-26.

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.

Intrathecal ropivacaine for ambulatory surgery

BACKGROUND

The rationale of this study was to evaluate intrathecal ropivacaine for ambulatory surgery.

METHODS

One hundred fifty patients with American Society of Anesthesiologists physical status 1 scheduled for knee arthroscopy were studied. Patients were randomly assigned to receive 4 ml of one of five isobaric intrathecal solutions: Patients in group 1 (n = 30) received 8 mg of bupivacaine; patients in group 2 (n = 30) received 8 mg ropivacaine; patients in group 3 (n = 30) received 10 mg ropivacaine; patients in group 4 (n = 30) received 12 mg ropivacaine; and patients in group 5 (n = 30) received 14 mg ropivacaine. The level and duration of sensory anesthesia were recorded along with the intensity and duration of motor block. Patients were interviewed to identify transient neurologic symptoms.

RESULTS

Intrathecal ropivacaine 10 mg produced shorter sensory anesthesia and motor blockade than bupivacaine 8mg (152 +/- 44 min and 135 +/- 41 min vs. 181 +/- 44 min and 169 +/- 52 min, mean +/- SD; P < 0.05). However, the quality of intraoperative analgesia was significantly lower in the 10-mg ropivacaine group (P < 0.05). Ropivacaine 12 mg produced sensory and motor block almost comparable to bupivacaine 8 mg. Ropivacaine 14 mg produced sensory and motor block comparable to ropivacaine 12 mg but significantly increased the time to void. No sign of transient radicular irritation were noted.

CONCLUSION

Intrathecal ropivacaine 12 mg is approximately equivalent to bupivacaine 8 mg. At this dose, ropivacaine offers no significant advantage compared with bupivacaine.

Intrathecal clonidine combined with sufentanil for labor analgesia

BACKGROUND

Intrathecal sufentanil provides rapid-onset and complete analgesia for the first stage of labor. The dose required to produce this effect can be associated with maternal respiratory depression, hypotension, nausea, or pruritus. Because clonidine potentiates the analgesic effects of opioids without increasing their side effects, the authors wanted to determine the efficacy of low doses of intrathecal clonidine (15 and 30 microg) combined with sufentanil.

METHODS

Ninety-eight parturient requesting labor analgesia were studied. In a combined spinal-epidural technique, patients were randomly assigned to receive one of the following intrathecal solutions: either 15 microg clonidine (n = 10); 30 microg clonidine (n = 10); 2.5 microg sufentanil (n = 13); 5 microg sufentanil (n = 13); 2.5 microg sufentanil and 15 microg clonidine (n = 13); 2.5 microg sufentanil and 30 microg clonidine (n = 13); 5 microg sufentanil and 15 microg clonidine (n = 13); or 5 microg sufentanil and 30 microg clonidine (n = 13). Visual analog scores for pain, blood pressure, heart rate, sensory levels, incidence of nausea and pruritus, and motor blockade, and maternal and cord blood concentrations of clonidine were recorded.

RESULTS

Patients receiving 30 microg intrathecal clonidine with 2.5 or 5 microg intrathecal sufentanil had significantly longer-lasting analgesia (145 +/- 36 and 145 +/- 43 min vs. 104 +/- 35 for those receiving 5 microg intrathecal sufentanil alone). Clonidine levels were undetectable in maternal serum.

CONCLUSIONS

Thirty micrograms of intrathecal clonidine combined with 2.5 or 5 microg intrathecal sufentanil significantly increased the duration of analgesia during the first stage of labor without adverse maternal or fetal effects.

Ambulatory combined spinal-epidural analgesia for labor. Influence of epinephrine on bupivacaine-sufentanil combination

BACKGROUND AND OBJECTIVES

Subarachnoid sufentanil 5 micrograms during labor is known to have variable results. However, subarachnoid sufentanil 5 micrograms plus bupivacaine 1 mg provides good quality labor analgesia of 100 minutes' average duration. The objective of this study was to examine the effects of adding epinephrine 25 micrograms to this mixture.

METHODS

Forty-two parturients with less than 5 cm cervical dilation participated in this double-blind, randomized study. A combined spinal-epidural technique was used for subarachnoid administration of sufentanil 5 micrograms and bupivacaine 1 mg with or without epinephrine 25 micrograms. Analgesia was assessed by visual analog scores. Time elapsed until first request for additional analgesia, blood pressure, heart rate, sensory levels, motor block, and incidence of pruritus, nausea, and sedation were noted.

RESULTS

Addition of epinephrine prolonged the duration of analgesia from 103.8 +/- 28.2 minutes to 142 +/- 54.3 minutes and lowered the median cephalad level of sensory block from T3 to T6. The incidence of side effects was similar in both groups, as was the motor performance; 19 patients were able to ambulate in each group.

CONCLUSIONS

This minimal bupivacaine-sufentanil-epinephrine mixture allows high-quality analgesia of 142 +/- 54.3 minutes' duration, with a low sensory block level and no motor block. However, hypotension can occur as a late side effect.

Fatal Capnocytophaga canimorsus septicemia in a previously healthy woman

A previously healthy 47-year-old woman presented to the emergency department with septic shock five days after a small dog bite on the dorsum of her hand. Capnocytophaga canimorsus was isolated from blood cultures. Despite intensive therapy, multiple organ failure developed, and the patient died 27 days after admission. Characteristics of Capnocytophaga (formerly CDC group Dysgonic Fermenter-2) infection are briefly discussed. This unusual outcome in a previously healthy patient and the need for careful management of dog bite wounds, even if initially very small, is emphasized.

Intensive care management of Guillain-Barré syndrome during pregnancy

A particularly severe case of Guillain-Barré syndrome occurring during pregnancy is reported. The therapeutic approach including plasmapheresis, ventilation, analgesia, sedation, metabolic requirements and heparin therapy is discussed with the consequences on foetal development and the early days of life.

Guillain-Barre syndrome after obstetrical epidural analgesia

Guillain Barre Syndrome (GBS) occurred 24 hours post-partum following an obstetrical epidural anesthetic (OEA) procedure. Clinical diagnosis was confirmed by cerebrospinal fluid (CSF) findings and nerve conduction velocity studies. GBS is an immune mediated process. Because of short latency between the onset of symptoms and the performance of the epidural block, a cause and effect relationship between epidural block and GBS in this patient is unlikely.