Use of Intravenous Acetaminophen in Children for Analgesia After Spinal Fusion Surgery: A Randomized Clinical Trial

Comparison of preemptive and preventive intravenous acetaminophen on opioid consumption in pediatrics undergoing posterior spinal fusion surgery: a randomized controlled trial

BACKGROUND

Posterior spinal fusion (PSF), commonly used for adolescent idiopathic scoliosis (AIS), causes severe postoperative pain. Intravenous (IV) administration of acetaminophen has shown promise for opioid-sparing analgesia; however, its analgesic effect and optimal timing for its standard use remain unclear. Our study aimed to evaluate the analgesic effect and optimal timing of IV acetaminophen administration in pediatric and adolescent patients undergoing PSF and requiring adequate pain control.

METHODS

This prospective, randomized, triple-blind trial was conducted in patients aged 11-20 undergoing PSF. Participants were randomized into three groups: the preemptive group (received IV acetaminophen 15 mg/kg after anesthetic induction/before surgical incision), the preventive group (received IV acetaminophen 15 mg/kg at the end of surgery/before skin closure), and the placebo group. The primary outcome was cumulative opioid consumption during the first 24 h postoperatively.

RESULTS

Among the 99 enrolled patients, the mean ± standard deviation (SD) amount of opioid consumption during the postoperative 24 h was 60.66 ± 23.84, 52.23 ± 22.43, and 66.70 ± 23.01 mg in the preemptive, preventive, and placebo groups, respectively (overall P = 0.043). A post hoc analysis revealed that the preventive group had significantly lower opioid consumption than the placebo group (P = 0.013). However, no significant differences between the groups were observed for the secondary outcomes.

CONCLUSIONS

The preventive administration of scheduled IV acetaminophen reduces cumulative opioid consumption without increasing the incidence of drug-induced adverse events in pediatric and adolescent patients undergoing PSF.

Systematic Review of Systemic and Neuraxial Effects of Acetaminophen in Preclinical Models of Nociceptive Processing

Acetaminophen (APAP) in humans has robust effects with a high therapeutic index in altering postoperative and inflammatory pain states in clinical and experimental pain paradigms with no known abuse potential. This review considers the literature reflecting the preclinical actions of acetaminophen in a variety of pain models. Significant observations arising from this review are as follows: 1) acetaminophen has little effect upon acute nociceptive thresholds; 2) acetaminophen robustly reduces facilitated states as generated by mechanical and thermal hyperalgesic end points in mouse and rat models of carrageenan and complete Freund’s adjuvant evoked inflammation; 3) an antihyperalgesic effect is observed in models of facilitated processing with minimal inflammation (eg, phase II intraplantar formalin); and 4) potent anti-hyperpathic effects on the thermal hyperalgesia, mechanical and cold allodynia, allodynic thresholds in rat and mouse models of polyneuropathy and mononeuropathies and bone cancer pain. These results reflect a surprisingly robust drug effect upon a variety of facilitated states that clearly translate into a wide range of efficacy in preclinical models and to important end points in human therapy. The specific systems upon which acetaminophen may act based on targeted delivery suggest both a spinal and a supraspinal action. Review of current targets for this molecule excludes a role of cyclooxygenase inhibitor but includes effects that may be mediated through metabolites acting on the TRPV1 channel, or by effect upon cannabinoid and serotonin signaling. These findings suggest that the mode of action of acetaminophen, a drug with a long therapeutic history of utilization, has surprisingly robust effects on a variety of pain states in clinical patients and in preclinical models with a good therapeutic index, but in spite of its extensive use, its mechanisms of action are yet poorly understood.

Comparison of interventions and outcomes of enhanced recovery after surgery: a systematic review and meta-analysis of 2456 adolescent idiopathic scoliosis cases

PURPOSE

The objective of this meta-analysis and systematic review is to compare the methodology and evaluate the efficacy of Enhanced recovery after Spine Surgery (ERAS) for adolescent idiopathic scoliosis (AIS) and to compare the outcomes with traditional discharge (TD) pathways.

METHODS

Using major databases, a systematic search was performed. Studies comparing the implementation of ERAS or ERAS-like and TD pathways in patients with AIS were identified. Data regarding methodology and outcomes were collected and analyzed.

RESULTS

Fourteen studies (n = 2456) were included, comprising 1081 TD and 1375 ERAS or ERAS-like patients. Average age of patients was 14.6 ± 0.4 years. Surgical duration was on average 35.6 min shorter for the ERAS group compared to TD cohort ([2.8, 68.3], p = 0.03), and blood loss was 112.3 milliliters less ([102.4, 122.2], p < 0.00001). ERAS group reached first ambulation 29.6 h earlier ([11.2, 48.0], p-0.002), patient-controlled-analgesia (PCA) discontinuation 0.53 day earlier ([0.4, 0.6], p < 0.00001), urinary catheter discontinuation 0.5 day earlier ([0.4, 0.6], p < 0.00001), and length-of-stay (LOS) was 1.6 days shorter ([1.4, 1.8], p < 0.00001). Rates of complications and 30-day-readmission-to-hospital were similar between both groups. Pain scores were significantly lower for ERAS group on days 0 through 2 post-operatively.

CONCLUSIONS

Use of ERAS after AIS is safe and effective, decreasing surgical duration and blood loss. ERAS methodology effectively focused on reducing time to first ambulation, PCA discontinuation, and urinary catheter removal. Outcomes showed significantly decreased LOS without a significant increase in complications. There should be efforts to incorporate ERAS in AIS surgery. Further studies are necessary to assess patient satisfaction.

LEVEL OF EVIDENCE III

Meta-analysis of Level 3 studies.

Does Intravenous Acetaminophen Reduce Opioid Requirement in Pediatric Emergency Department Patients With Acute Sickle Cell Crises?

OBJECTIVE

We evaluated the ability of intravenous (IV) acetaminophen to reduce the amount of opioid medication administered in pediatric patients with sickle cell disease (SCD) having vasoocclusive crisis (VOC) in an emergency department (ED) setting.

METHODS

This was a prospective, randomized, double-blind placebo-controlled trial at an academic urban pediatric ED. Participants included patients with SCD, aged 4 to 16 years, with VOC pain. All patients received a 0.1 mg/kg dose of IV morphine, 0.5 mg/kg ketorolac, or both. Patients were randomized to receive either 15 mg/kg IV acetaminophen or placebo. Patients were reassessed every 30 minutes to see whether additional opioid doses were indicated to a maximum of three doses. The total morphine given, pain scores, rates of admissions, 72-hour return visits, and adverse events were assessed for each group.

RESULTS

Of 71 subjects randomized, 35 patients in the acetaminophen group and 36 patients in the control group were analyzed. Baseline characteristics and initial pain scores were similar in both groups. The mean total amount of morphine given was 8.6 mg (95% confidence interval [CI] = 6.5 to 10.8) in the acetaminophen group and 8.0 mg (95% CI = 5.9 to 10.2) in the placebo group. The mean total cumulative morphine dosing was 0.2 mg/kg (95% CI = 0.1 to 0.2 mg/kg) in the acetaminophen group and 0.2 mg/kg (95% CI = 0.1 to 0.2 mg/kg) in the control group. The mean pain score at time of disposition was 5.5 (95% CI = 4.3 to 6.6) in the acetaminophen group and 5.2 (95% CI = 4.2 to 6.3) in the placebo group. There were no clinical or statistically significant differences between the rates of admission, 72-hour return visits, or adverse events.

CONCLUSION

In this study, patients who received IV acetaminophen did not receive less morphine than patients in the placebo group. Disposition pain scores for the two groups were also equivalent. We conclude that IV acetaminophen, when used in addition to morphine for pediatric sickle cell VOC pain, does not provide an opioid-sparing effect. Further searches for adjunctive nonaddictive pain medicines are indicated.

Quantification evaluation of structural autograft versus morcellized fragments autograft in patients who underwent single-level lumbar laminectomy

Posterolateral fusion (PLIF) with autogenous bone graft is considered the gold standard for lumbar spinal fusion. However, the fusion rate and effectiveness of locally derived corticocancellous structural autograft vs. morcellized fragments autograft for lumbar PLIF, following single level lumbar laminectomy in patients with symptomatic lumbar spinal stenosis, remain unknown. Thus, the present study aimed to compare the fusion rates of corticocancellous structural autograft and morcellized fragments autograft for the treatment of lumbar PLIF. A randomized self-controlled trial was conducted comprising of 135 patients with symptomatic lumbar spinal stenosis, single level lumbar laminectomy and PLIF, with corticocancellous structural autograft (group 1) and morcellized fragments autograft (group 2). The primary outcome measurements included the PLIF rate, radio density and dimensions of PLIF mass on both sides, which were assessed via X-rays at 3, 6 and 12 months, postoperatively. Furthermore, changes in bilateral bone fusion bridges were assessed via CT scanning, according to the Lenke CT fusion measurement criteria. The follow-up period lasted for 1 year (period between January 2013 and January 2018). Of the 135 patients were initially included in the present study, 7 patients were lost during the following up process. Therefore, data from 128 patents were eventually assessed, 94.8% of surgical levels were observed at Honghui Hospital. According to the Lenke CT fusion measurement criteria, the overall unilateral fusion rates were 71.9% (92/128) in group 1 and 31.3% (40/128) in group 2. Furthermore, both the radio density and dimensions of PLIF mass significantly decreased at a faster rate in group 1 compared with group 2 (radio density; 0.65-0.49 vs. 0.63-0.61; P<0.05 and PLIF mass; 398-124 vs. 376-223 mm²; P<0.05). The CT scan results demonstrated that the mean volume of bone graft was significantly greater in group 1 compared with group 2, at 12 months postoperatively (1.47 vs. 1 cm³; P<0.05). Taken together, the results of the present study suggested that corticocancellous structural autograft is more effective for earlier resorption and stabilization of patients undergoing PLIF, compared with morcellized fragments autograft.