Narcotic Consumption Following Minimally Invasive Lumbar Decompression: A Comparison Between Hospital and Ambulatory-Based Surgery Centers.

BACKGROUND: Several studies have compared outcomes between hospital-based centers (HBCs) and ambulatory surgery centers (ASCs) following minimally invasive lumbar decompression (MIS LD). However, the association between narcotic consumption and pain in the immediate postoperative period has not been well characterized. As such, this study aims to examine pain, narcotic consumption, and length of stay (LOS) among patients discharged on postoperative day 0 following a 1-level MIS LD between HBCs or ASCs. METHODS: Patients who underwent a primary, 1-level MIS LD were retrospectively reviewed and stratified by operative location. Differences between groups in patient demographics were assessed using independent-sample t tests for continuous variables and χ2 analysis for categoric variables. The operative location and its effect on perioperative characteristics, inpatient pain scores, and narcotics consumption were analyzed using multivariate linear regression adjusted for significant patient characteristics. RESULTS: There were 235 patients identified, of whom 90 and 145 underwent surgery at an HBC or ASC, respectively. The HBC cohort exhibited an increased comorbidity burden and had a greater percentage of privately insured patients. The HBC cohort recorded shorter operative time and greater total estimated blood loss. Patients in the HBC cohort experienced prolonged LOS, and consumed greater total oral morphine equivalents compared with the ASC cohort. No differences were observed in the remaining outcomes. CONCLUSIONS: The results of the current study suggest that patients who underwent MIS LD at an ASC received fewer narcotics than patients treated at an HBC, which may contribute to shortened LOS. Additionally, there was no difference in patient-reported pain between cohorts despite the differences in narcotic use. As such, postoperative narcotics administration varied, indicating HBC patients perhaps required more narcotic pain medications to achieve the same pain scores that were sufficient enough to allow patient discharge, thus prolonging LOS. LEVEL OF EVIDENCE: III.

PROMIS Physical Function for prediction of postoperative pain, narcotics consumption, and patient-reported outcomes following minimally invasive transforaminal lumbar interbody fusion.

OBJECTIVEThis study aimed to determine if the preoperative Patient-Reported Outcomes Measurement Information System, Physical Function (PROMIS PF) score is predictive of immediate postoperative patient pain and narcotics consumption or long-term patient-reported outcomes (PROs) following minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).METHODSA prospectively maintained database was retrospectively reviewed. Patients who underwent primary, single-level MIS TLIF for degenerative pathology were identified and grouped by their preoperative PROMIS PF scores: mild disability (score 40-50), moderate disability (score 30-39.9), and severe disability (score 20-29.9). Postoperative pain was quantified using the visual analog scale (VAS), and narcotics consumption was quantified using Oral Morphine Equivalents. PROMIS PF, Oswestry Disability Index (ODI), 12-Item Short-Form Health Survey, Physical Component Summary (SF-12 PCS), and VAS back and leg pain were collected preoperatively and at 6-week, 3-month, 6-month, and 12-month follow-up. Preoperative PROMIS PF subgroups were tested for an association with demographic and perioperative characteristics using 1-way ANOVA or chi-square analysis. Preoperative PROMIS PF subgroups were tested for an association with immediate postoperative pain and narcotics consumption in addition to improvements in PROMIS PF, ODI, SF-12 PCS, and VAS back and leg pain by using linear regression controlling for statistically different demographic characteristics.RESULTSA total of 130 patients were included in this analysis. Patients were grouped by their preoperative PROMIS PF scores: 15.4% had mild disability, 63.8% had moderate disability, and 20.8% had severe disability. There were no significant differences among the subgroups in terms of age, sex, smoking status, and comorbidity burden. Patients with greater disability were more likely to be obese and to have workers' compensation insurance. There were no differences among subgroups in regard to operative levels, operative time, estimated blood loss, and hospital length of stay. Patients with greater disability reported higher VAS pain scores and narcotics consumption for postoperative day 0 and postoperative day 1. Patients with greater preoperative disability demonstrated lower PROMIS PF, ODI, SF-12 PCS, and worse VAS pain scores at each postoperative time point.CONCLUSIONSPatients with worse preoperative disability, as assessed by PROMIS PF, experienced increased pain and narcotics consumption, along with less improvement in long-term PROs. The authors conclude that PROMIS PF is an efficient and accurate instrument that can quickly assess patient disability in the preoperative period and predict both short-term and long-term surgical outcomes.

The Patient-Reported Outcomes Measurement Information System in spine surgery: a systematic review.

OBJECTIVEThe Patient-Reported Outcomes Measurement Information System (PROMIS) was developed to provide a standardized measure of clinical outcomes that is valid and reliable across a variety of patient populations. PROMIS has exhibited strong correlations with many legacy patient-reported outcome (PRO) measures. However, it is unclear to what extent PROMIS has been used within the spine literature. In this context, the purpose of this systematic review was to provide a comprehensive overview of the PROMIS literature for spine-specific populations that can be used to inform clinicians and guide future work. Specifically, the authors aimed to 1) evaluate publication trends of PROMIS in the spine literature, 2) assess how studies have used PROMIS, and 3) determine the correlations of PROMIS domains with legacy PROs as reported for spine populations.METHODSStudies reporting PROMIS scores among spine populations were identified from PubMed/MEDLINE and a review of reference lists from obtained studies. Articles were excluded if they did not report original results, or if the study population was not evaluated or treated for spine-related complaints. Characteristics of each study and journal in which it was published were recorded. Correlation of PROMIS to legacy PROs was reported with 0.1 ≤ |r| < 0.3, 0.3 ≤ |r| < 0.5, and |r| ≥ 0.5 indicating weak, moderate, and strong correlations, respectively.RESULTSTwenty-one articles were included in this analysis. Twelve studies assessed the validity of PROMIS whereas 9 used PROMIS as an outcome measure. The first study discussing PROMIS in patients with spine disorders was published in 2012, whereas the majority were published in 2017. The most common PROMIS domain used was Pain Interference. Assessments of PROMIS validity were most frequently performed with the Neck Disability Index. PROMIS domains demonstrated moderate to strong correlations with the legacy PROs that were evaluated. Studies assessing the validity of PROMIS exhibited substantial variability in PROMIS domains and legacy PROs used for comparisons.CONCLUSIONSThere has been a recent increase in the use of PROMIS within the spine literature. However, only a minority of studies have incorporated PROMIS for its intended use as an outcomes measure. Overall, PROMIS has exhibited moderate to strong correlations with a majority of legacy PROs used in the spine literature. These results suggest that PROMIS can be effective in the assessment and tracking of PROs among spine populations.

The Impact of Comorbidity Burden on Complications, Length of Stay, and Direct Hospital Costs After Minimally Invasive Transforaminal Lumbar Interbody Fusion.

STUDY DESIGN: A retrospective cohort. OBJECTIVE: The aim of this study was to determine whether comorbidity as determined by Charlson Comorbidity Index (CCI) is associated with inpatient complication rate, length of stay (LOS), or direct hospital costs after minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). SUMMARY OF BACKGROUND DATA: In the spine literature, comorbidity burden has been associated with an increased risk for complications, prolonged LOS, and greater hospital costs. Few studies have investigated the influence of comorbidity burden on these outcomes in minimally invasive spine surgery populations. METHODS: A prospectively maintained surgical registry of patients undergoing primary, single-level MIS-TLIF was retrospectively reviewed. Patients were stratified by CCI and tested for association with preoperative demographics and perioperative characteristics using Chi-squared analysis or one-way analysis of variance for categorical and continuous variables, respectively. Complication rates, LOS, and direct hospital costs were compared between groups using a one-way analysis of variance. RESULTS: Two hundred ninety-eight patients were included. About 19.8% had a CCI of 0, 41.3% had a CCI of 1 to 2, 27.2% had a CCI of 3 to 4, and 11.7% had a CCI ≥ 5. Elevated CCI was associated with older age, smoking, and insurance status. Elevated CCI was significantly associated with a greater total inpatient complication rate. Regarding LOS and total direct hospital costs, there were no associations identified. However, elevated CCI was associated with greater costs accrued in the intensive care unit, laboratory costs, and cardiology-related costs. CONCLUSION: Greater comorbidity burden as reflected by higher CCI was associated with increased postoperative complication rates following primary, single-level MIS-TLIF. However, this did not lead to prolongations in hospital stay or increased total direct hospital costs. This lack of association may suggest that the limited tissue trauma and operative exposure utilized in minimally invasive approaches may limit the utility of CCI as a predictor of surgical outcomes and costs. LEVEL OF EVIDENCE: 4.

PROMIS Physical Function Score Strongly Correlates With Legacy Outcome Measures in Minimally Invasive Lumbar Microdiscectomy.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: This study aims to determine the validity of the patient-reported outcomes measurement information system (PROMIS) physical function (PF) in minimally invasive lumbar discectomy (MIS LD) patients. SUMMARY OF BACKGROUND DATA: PROMIS was designed to allow for assessment of clinical outcomes in fewer questions than previous outcome measures with the goal of reducing noncompliance associated with longer, time-consuming surveys. However, there exists a paucity of evidence regarding the efficacy of the PROMIS PF domain in patients undergoing MIS LD. METHODS: A surgical database of patients undergoing 1-3 level MIS LD was retrospectively reviewed. Postoperative changes in PROMIS PF scores were analyzed at 6-weeks, 12-weeks, and 6-months using paired Student t tests. PROMIS scores were compared to Oswestry disability index (ODI), visual analog scale (VAS) back, and VAS leg scores. Correlations were tested using Pearson correlation coefficient. RESULTS: Forty-one MIS LD patients were identified, reporting an average preoperative PROMIS PF score of 35.36 ±â€Š7. Patients demonstrated significant improvement in ODI, VAS back, and VAS leg scores. Additionally, strong associations with PROMIS scores were observed for preoperative and postoperative ODI (r range: 0.5735-0.8543) and postoperative VAS back (r range: 0.5332-0.6522) and VAS leg pain (r range: 0.5257-0.6412). CONCLUSION: Patients undergoing MIS LD demonstrated significant improvements in PROMIS PF, ODI, VAS back, and VAS leg pain postoperatively. Additionally, improvements in PROMIS physical function scores at each postoperative time point were determined to be significantly correlated with ODI, VAS back, and VAS leg pain. The results of the current study demonstrate PROMIS PF has strong utility as a postoperative outcome assessment tool. LEVEL OF EVIDENCE: 4.

The Effect of Preoperative Medications on Length of Stay, Inpatient Pain, and Narcotics Consumption After Minimally Invasive Transforaminal Lumbar Interbody Fusion.

STUDY DESIGN: This is a retrospective cohort study. OBJECTIVE: To determine the association between preoperative medications and length of stay, inpatient pain, and narcotics consumption after a minimally invasive transforaminal lumbar interbody fusion (MIS TLIF). SUMMARY OF BACKGROUND DATA: Previous studies have identified risk factors for increased length of hospital stay, inpatient pain, and narcotics consumption. However, little is known regarding the effects of preoperative medications on outcomes after spine surgery. METHODS: A prospectively maintained surgical database of patients undergoing primary, single-level MIS TLIF was retrospectively reviewed. Preoperative medications taken within 30 days before surgery were recorded for each patient and categorized by medication type. Poisson regression with robust error variance was used to determine the association between preoperative medications and length of stay, pain scores, and narcotics consumption. Multivariate analysis was performed using a backwards, stepwise regression to identify independent risk factors. RESULTS: In total, 138 patients were included in this analysis. On bivariate analysis, benzodiazepines were associated with longer hospital stays [relative risk (RR)=2.03; P=0.031]. Benzodiazepines (RR=3.71; P<0.001) and preoperative narcotics (RR=2.60; P=0.012) were risk factors for pain ≥7 on postoperative day 0. On multivariate analysis, benzodiazepines were an independent risk factor for prolonged stay. Benzodiazepines, narcotics, and nonsteroidal anti-inflammatories were identified as independent risk factors for increased postoperative pain. CONCLUSIONS: These results suggest that benzodiazepines are a risk factor for increased length of stay and postoperative pain after MIS TLIF. Preoperative narcotics and nonsteroidal anti-inflammatories were also identified as risk factors for postoperative pain though this did not lead to increases in narcotics consumption. Patients taking these medications should undergo more vigilant perioperative monitoring for adequate pain management. More work must be done to further elucidate the association between preoperative medications and postoperative outcomes after MIS TLIF.

Risk Factors for a Long Hospital Stay Following Minimally Invasive Lumbar Discectomy.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The purpose of the study was to determine risk factors for discharge after postoperative day (POD) 0 in patients undergoing 1-level minimally invasive lumbar discectomy (MIS LD). SUMMARY OF BACKGROUND DATA: MIS LD has proven to be an effective treatment modality for low back pain and radiculopathy associated with intervertebral disc herniations. With increasing focus on cost reduction and value-based care, minimization of postoperative length of stay has become an important topic for physicians and hospital administrators. METHODS: A prospectively maintained surgical database of patients who underwent 1-level MIS LD by a single surgeon from 2011 to 2016 was reviewed. Long length of stay was defined as discharge after POD 0. Bivariate and stepwise multivariate Poisson regression with robust error variance was used to determine risk factors for discharge after POD 0. Variables analyzed included patient demographics, comorbidities, operative characteristics, preoperative pain scores, postoperative inpatient pain scores, and postoperative narcotics consumption. RESULTS: A total of 176 patients were included; 9.7% of included patients were discharged on POD 1 or later. On bivariate analysis, diabetic status (57.1% vs. 7.7%; relative risk [RR]=7.43; P<0.01) and narcotic consumption <6.00 oral morphine equivalents/h (13.1% vs. 1.2%; RR=11.11; P=0.019) were associated with a prolonged length of stay. On stepwise multivariate analysis, diabetic status (RR=10.5; 95% confidence interval, 3.60-30.98; P<0.001) was found to be independently associated with a prolonged length of stay after MIS LD. CONCLUSIONS: The results indicate that diabetic status is an independent risk factor for increased LOS following single-level MIS LD. Delayed hospital discharge can lead to increased costs, increased risk of complications, and decreased patient satisfaction. Thus, providers can use this information to better counsel diabetic patients and monitor them more closely following MIS LD. Additional work must be done to better understand risk factors for increased length of stay following MIS LD in procedure-specific populations. LEVEL OF EVIDENCE: Level II.

The Effect of Preoperative Symptom Duration on Postoperative Outcomes After a Tubular Lumbar Microdiscectomy.

STUDY DESIGN: This is a retrospective cohort study. OBJECTIVE: This study aims to characterize the effect of preoperative symptom duration on postoperative outcomes after minimally invasive lumbar microdiscectomy (MIS LD). SUMMARY OF BACKGROUND DATA: It is unknown whether extended nonoperative treatment before MIS LD has implications for long-term clinical outcomes even after surgery is performed. MATERIALS AND METHODS: A prospectively maintained surgical registry of patients undergoing MIS LD by a single surgeon between 2013 and 2017 was reviewed. Preoperative symptom duration was dichotomized into 2 groups (≤6 and >6 mo). Only patients with full clinical data at 6 months postoperative follow-up were included in the study. Clinical outcomes were assessed at 6, 12 weeks, and 6 months after surgery. The number of patients obtaining a minimum clinically important difference was assessed. Groups were compared with the χ analysis and the student t tests for categorical and continuous data, respectively. RESULTS: In total, 94 patients were identified. A total of 45 patients (47.9%) had symptom duration ≤6 months. No differences in baseline characteristics were found (P>0.05). Patients with shorter symptom duration had significantly greater improvement in Oswestry Disability Index scores at 6 weeks (P=0.004), 12 weeks (P=0.022), and 6 months (P=0.005). Patients with shorter duration of symptoms also obtained minimum clinically important difference for Oswestry Disability Index at a greater rate than those with longer duration of symptoms (P=0.015). CONCLUSIONS: Although patients who underwent MIS LD within 6 months of symptom onset had similar baseline characteristics compared with patients who underwent surgery after 6 months of symptoms, the patients with longer preoperative symptom duration had worse functional outcomes at 6 months after surgery. These results suggest that earlier MIS lumbar microdiscectomy may provide a functional benefit for patients. Further studies should therefore evaluate the efficacy of nonoperative treatment in the setting of lumbar herniated nucleus pulposus, as prolonged conservative management may potentially impair functional recovery after surgery.

Impact of local steroid application in a minimally invasive transforaminal lumbar interbody fusion: results of a prospective, randomized, single-blind trial.

OBJECTIVELocal epidural steroid application may be associated with decreased pain and narcotic use in the immediate postoperative period following lumbar discectomy. However, local steroid delivery following lumbar fusion procedures has not been well characterized. This study aims to characterize the effect of local intraoperative depomedrol application on perioperative and postoperative outcomes following a single-level minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).METHODSA prospective, randomized, single-blinded study was performed. A priori power analysis determined that 86 patients were needed to detect a difference of 1 point in the visual analog scale (VAS) pain score between groups. Ninety-three patients were randomized into depomedrol (DEPO) and no depomedrol (NODEPO) cohorts. Prior to surgical closure, DEPO patients received 1 ml depomedrol (80 mg) applied directly to the surgical site by using a Gelfoam carrier. NODEPO patients received 1 ml saline on the same Gelfoam carrier. Perioperative outcomes including acute postoperative pain and narcotic use were assessed for the duration of inpatient stay. Patient-reported outcomes (PROs) questionnaires including VAS back and leg pain scores, and Oswestry Disability Index (ODI) were administered preoperatively and at 6-week, 12-week, and 6-month follow-up. Outcomes for DEPO and NODEPO cohorts were compared using linear regression controlled for sex.RESULTSOf the 93 patients, 45 (48.4%) were randomized to DEPO and 48 (51.6%) to NODEPO. A greater percentage of DEPO patients were female (53.3% vs 27.1%, p = 0.010). There were no other significant differences in patient baseline characteristics. Similarly, operating time, estimated blood loss, and length of inpatient stay did not differ between cohorts. Patients in the DEPO cohort consumed fewer hourly narcotics on postoperative day 0 (5.3 vs 6.3 oral morphine equivalents/hour, p = 0.034). However, no differences in acute postoperative pain or total narcotics consumption were observed between groups. Preoperative VAS leg scores were statistically different between cohorts (p = 0.027). However, preoperative ODI and VAS back scores did not differ between groups. Additionally, DEPO and NODEPO groups experienced similar improvements in PROs at all postoperative time points.CONCLUSIONSLocal depomedrol use did not lead to decreases in acute postoperative pain or narcotics consumption after MIS TLIF. Additionally, local depomedrol was not associated with postoperative improvements in PROs. The findings of this randomized trial suggest that surgical and clinical outcomes following MIS TLIF may not be impacted by intraoperative application of depomedrol.Clinical trial registration no.: NCT03308084 (clinicaltrials.gov).