Continuous chloroprocaine paravertebral infusions for postoperative analgesia in infants and very young children

Perioperative Regional Anesthesia Pain Outcomes in Children: A Retrospective Study of 3160 Regional Anesthetics in Routine Practice

OBJECTIVE

Randomized controlled trials indicate regional anesthesia (RA) improves postoperative outcomes with reduced pain and opioid consumption. Therefore, we hypothesized children who received RA, regardless of technique, would have reduced pain/opioid use in routine practice.

METHODS

Using a retrospective cohort, we assessed the association of RA with perioperative outcomes in everyday practice at our academic pediatric hospital. Patients 18 years or below undergoing orthopedic, urologic, or general surgeries with and without RA from May 2014 to September 2021 were categorized as single shot, catheter based, or no block. Outcomes included intraoperative opioid exposure and dose, preincision anesthesia time, postanesthesia care unit (PACU) opioid exposure and dose, PACU antiemetic/antipruritic administration, PACU/inpatient pain scores, PACU/inpatient lengths of stay, and cumulative opioid exposure. Regression models estimated the adjusted association of RA with outcomes, controlling for multiple variables.

RESULTS

A total of 11,292 procedures with 3160 RAs were included. Compared with no-block group, single-shot and catheter-based blocks were associated with opioid-free intraoperative anesthesia and opioid-free PACU stays. Post-PACU (ie, while inpatient), single-shot blocks were not associated with improved pain scores or reduced opioid use. Catheter-based blocks were associated with reduced PACU and inpatient opioid use until 24 hours postop, no difference in opioid use from 24 to 36 hours, and a higher probability of use from 36 to 72 hours. RA was not associated with reduced cumulative opioid consumption.

DISCUSSION

Despite adjustment for confounders, the association of RA with pediatric pain/opioid use outcomes was mixed. Further investigation is necessary to maximize the benefits of RA.

Evolving approaches in neonatal postoperative pain management

Neonates experience significant moderate and severe postoperative pain. Effective postoperative pain management in neonates is required to minimize acute and long-term effects of neonatal pain. Protecting the developing nervous system from persistent sensitization of pain pathways and developing primary hyperalgesia is essential. Opioids and acetaminophen are commonly analgesics used for pain control. Regional anesthesia provides adequate intraoperative and postoperative analgesia in neonates. It decreases exposure to opioids, reduces adverse drug effects, and facilitates early extubation. It suppresses the stress response and can prevent long-term behavioral responses to pain. The most common blocks performed in neonates are neuraxial blocks. Using ultrasound increased the number of peripheral nerve blocks performed in neonates. Recently, various peripheral nerve blocks (paravertebral, transverse abdominis plane, rectus sheath, quadratus lumborum, erector spinae plane blocks) were safely used. Many studies support analgesic efficacy but highlight neonates' unpredictability and variability of fascial blocks.

Evaluation of neurotoxicity and long-term function and behavior following intrathecal 1 % 2-chloroprocaine in juvenile rats

Spinally-administered local anesthetics provide effective perioperative anesthesia and/or analgesia for children of all ages. New preparations and drugs require preclinical safety testing in developmental models. We evaluated age-dependent efficacy and safety following 1 % preservative-free 2-chloroprocaine (2-CP) in juvenile Sprague-Dawley rats. Percutaneous lumbar intrathecal 2-CP was administered at postnatal day (P)7, 14 or 21. Mechanical withdrawal threshold pre- and post-injection evaluated the degree and duration of sensory block, compared to intrathecal saline and naive controls. Tissue analyses one- or seven-days following injection included histopathology of spinal cord, cauda equina and brain sections, and quantification of neuronal apoptosis and glial reactivity in lumbar spinal cord. Following intrathecal 2-CP or saline at P7, outcomes assessed between P30 and P72 included: spinal reflex sensitivity (hindlimb thermal latency, mechanical threshold); social approach (novel rat versus object); locomotor activity and anxiety (open field with brightly-lit center); exploratory behavior (rearings, holepoking); sensorimotor gating (acoustic startle, prepulse inhibition); and learning (Morris Water Maze). Maximum tolerated doses of intrathecal 2-CP varied with age (1.0 μL/g at P7, 0.75 μL/g at P14, 0.5 μL/g at P21) and produced motor and sensory block for 10-15 min. Tissue analyses found no significant differences across intrathecal 2-CP, saline or naïve groups. Adult behavioral measures showed expected sex-dependent differences, that did not differ between 2-CP and saline groups. Single maximum tolerated in vivo doses of intrathecal 2-CP produced reversible spinal anesthesia in juvenile rodents without detectable evidence of developmental neurotoxicity. Current results cannot be extrapolated to repeated dosing or prolonged infusion.

Local anesthetic systemic toxicity in children: a review of recent case reports and current literature

BACKGROUND

Local anesthetic systemic toxicity (LAST) in children occurs at an estimated rate of 8 per 100 000 blocks (95% CI 0.3 to 1.6). Due to the potential lethality of this iatrogenic complication, a better clarity of risk factors, clinical presentation, and prognosis may be clinically useful for contemporary treatment and prevention.

METHODS

An extensive literature search and detailed analysis of reported cases of LAST in patients less than 18 years of age published between April 2014 and August 2019 was performed. Clinical patterns were summarized.

RESULTS

Thirty-two cases of LAST were described in 17 published articles and 2 additional cases reported to lipidrescue.org, for a total of 34 cases. Three patients did not meet the inclusion criteria. Thirty-one cases were included in the analysis.

DISCUSSION

Infants represented a disproportionately large number of reports of LAST. The majority of local anesthetic doses were within currently published guidelines. Among the reported cases, penile and caudal blocks were the most commonly associated with LAST. Needle aspiration and test dosing with epinephrine failed to predict LAST with certainty. When LAST presented with severe cardiac compromise, intravenous lipid emulsion was given within 10 min in 43% of cases (13 of 30 reported cases). The vast majority of children were under general anesthesia when local anesthetic medications were administered. In children under general anesthesia, LAST presented with cardiac manifestations in 90% of cases (19 of 21 cases). There were no deaths or long-term morbidity reported.