Use of Gabapentin in Posterior Spinal Fusion is Associated With Decreased Postoperative Pain and Opioid Use in Children and Adolescents

Abstract

Study Design: Retrospective cohort study. Objective: The objective of this study was to examine associations of gabapentin use with inpatient postoperative daily pain scores and opioid use in children undergoing PSF for AIS. Summary of Background Data: Gabapentin use in posterior spinal fusion (PSF) postoperative pain management for adolescent idiopathic scoliosis (AIS) is increasingly common in order to decrease opioid use and improve pain control, though there is conflicting data on dosing and effectiveness to support this practice in real world settings. Methods: Retrospective cohort study of children aged 10 to 21 years undergoing PSF for AIS between January 2013 and June 2016 at an urban academic tertiary care center. Adjuvant gabapentin exposure was defined as at least 15 mg/kg/d by postoperative day (POD) 1 with an initial loading dose of 10 mg/kg on day of surgery. Primary outcomes were daily postoperative mean pain score and opioid use [morphine milligram equivalents/kg/day(mme/kg/d)]. Secondary outcomes were short and long-term complications. Results: Among 129 subjects (mean age, 14.6 y, 74% female, mean coronal cobb, 55.2 degrees), 24 (19%) received gabapentin. Unadjusted GABA exposure was associated with significantly lower opioid use on POD1 and 2 (49% and 31%mme/kg/d, respectively) and lower pain scores (14%) on POD2. Adjusting for preexisting back pain, preoperative coronal Cobb angle, and site, GABA use was associated with significantly lower mean pain scores on POD1 through POD3 (−0.68, P=0.01; −0.86, P=0.002; −0.63, P=0.04). Gabapentin use was also associated with decreased opioid use on POD1 and POD2 (−0.39mme/kg/d, P<0.001; −0.27, P=0.02). There was no difference in complications by gabapentin exposure. Conclusions: Addition of gabapentin as adjuvant therapy for adolescent PSF, beginning on day of surgery, is associated with improved pain scores and decreased opioid use in the first 48 to 72 hours postoperatively. Level of Evidence: This is a retrospective cohort study, classified as Level III under “Therapeutic Studies Investigating the Results of a Treatment.”

Gabapentin and Intrathecal Morphine Combination Therapy Results in Decreased Oral Narcotic Use and More Consistent Pain Scores After Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis

“…Trzcinski et al reported nausea/vomiting in 75% of their entire retrospective cohort. 5 The patients who received perioperative gabapentin in our study experienced a signi cantly lower rate of postoperative nausea/vomiting and pruritus, possibly secondary to receiving a lower dose of intrathecal morphine. However, this difference may also be directly related to antiemetic effects of gabapentin at central nervous system sites 18 as some prior studies have shown that it appears to have antiemetic effects in at least some patient populations, 19 including spinal surgery.…”

“…Similarly, Trzcinski et al retrospectively found that patients who received perioperative gabapentin had improved pain scores and decreased opioid use for 48 to 72 hours after surgery. 5 Thomas et al demonstrated a decrease in time to complete physical therapy goals when patients received perioperative gabapentin but there was no difference in length of hospital stay. 4 Choudhry et al retrospectively showed that PSF patients who received perioperative gabapentin combined with intravenous PCA had decreased total PCA doses, decreased morphine use on POD 1, and shorter time to transition to orals compared to patients who received PCA alone.…”

“…1 Prior studies have shown no difference in the rate of adverse events, including postoperative nausea/vomiting, pruritus, and oversedation, with the addition of perioperative gabapentin to intravenous PCA after PSF for AIS. 1,3,5 Nausea/vomiting is a common adverse event after PSF. Trzcinski et al reported nausea/vomiting in 75% of their entire retrospective cohort.…”

“…Multimodal pain management has been found to improve the quality of analgesia and reduce medication-related side effects after posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS). [1][2][3][4][5][6][7] Prior studies have shown that perioperative gabapentin, an effective drug for neuropathic pain, combined with intravenous patient-controlled analgesia (PCA) reduces initial postoperative pain scores, postoperative opioid use, and time to completing physical therapy goals compared to PCA alone after PSF for AIS. 1,3−5 Postoperative pain is not a Food and Drug Administration-approved indication for gabapentin usage.…”

Trajectory analysis for postoperative pain using electronic health records: A nonparametric method with robust linear regression and K-medians cluster analysis

“…The trajectory analyses were compared with other basic analytical approaches that are common in the literature, that is last recorded pain score, mean pain score on discharge day, and max pain score on discharge day (Supplementary Figure 1). 27 –30 In terms of predictions and model fits, our trajectory analyses outperform all the single score discharge pain methods in regard to their area under curve (AUC) and Akaike information criterion (AIC). (Supplementary Table 3).…”