Risk factors and associated complications for postoperative urinary retention after lumbar surgery for lumbar spinal stenosis

Intraoperative bulbocavernosus reflex monitoring for predicting postoperative voiding dysfunction in patients with distal intraspinal tumors

OBJECTIVE

To investigate the predictive value of intraoperative bulbocavernosus reflex (BCR) monitoring for voiding dysfunction post-operatively in patients with distal intraspinal tumors and to determine an appropriate timing for postoperative follow-up assessment.

METHODS

Patients with distal intraspinal tumors who underwent surgery with BCR monitoring were collected. Patients were classified into BCR absent and present groups according to the monitoring responses at the end of surgery. Voiding function was evaluated at 1 week, 2 months, 4 months, and 6 months after surgery.

RESULTS

A total of 52 patients were included. There were 30 (57.7 %) males and the mean age was (48.6 ± 17.2) years. Forty-nine (94.2 %) patients were adult. BCR was preserved in 50 (96.2 %) patients and completely disappeared in 2 cases at the end of the surgery. The sensitivity of intraoperative BCR loss for worsened voiding were 20.0 %, 33.3 %, 66.7 %, and 100.0 % at 1 week, 2 months, 4 months, and 6 months post-operatively respectively. The specificity was all 100.0 % at the four follow-ups. Preoperative voiding difficulty was more common in patients suffering from worsened voiding than those maintained at 1 week post-operatively (P < 0.05).

CONCLUSIONS

Intraoperative BCR monitoring is a reliable technique to predict the postoperative voiding dysfunction in patients with distal intraspinal tumors. Preservation of the BCR is a robust indication for favorable postoperative urinary function as time goes on and 6-month post-operatively may be an optimal timing for functional assessment with high sensitivity and specificity. Preoperative voiding symptoms may be a risk factor for voiding difficulty at early stage after surgery.

Economic Impact of Postoperative Urinary Retention in the US Hospital Setting

Background: Postoperative urinary retention (POUR) is a common and distressing surgical complication that may be associated with the pharmacological reversal technique of neuromuscular blockade (NMB). Objective: This study aimed to investigate the impact that POUR has on medical charges. Methods: This was a retrospective observational study of adult patients undergoing select surgeries who were administered neuromuscular blockade agent (NMBA), which was pharmacologically reversed between February 2017 and November 2021 using data from the PINC-AI™ Healthcare Database. Patients were divided into 2 groups: those experiencing POUR (composite of retention of urine, insertion of temporary indwelling bladder catheter, insertion of non-indwelling bladder catheter) during index hospitalization following surgery and those without POUR. Surgeries in inpatient and outpatient settings were analyzed separately. A cross-sectional comparison was performed to report total hospital charges for the 2 groups. Furthermore, patients experiencing subsequent POUR events within three days after discharge from index hospitalization were studied. Results: A total of 330 838 inpatients and 437 063 outpatients were included. POUR developed in 13 020 inpatients and 2756 outpatients. Unadjusted results showed that POUR was associated with greater charges in both inpatient ( 92   529 w i t h P O U R v s 78 556 without POUR, p < .001) and outpatient ( 48   996 w i t h P O U R v s 35 433 without POUR, p < .001) settings. After adjusting for confounders, POUR was found to be associated with greater charges with an overall mean adjusted difference of 10   668 ( 95 95 760- 11   760 , p   <   .001 ) i n i n p a t i e n t a n d 13 160 (95% CI 11   750 - 14  571, p < .001) in outpatient settings. Charges associated with subsequent POUR events following discharge ranged from 9418 i n p a t i e n t c h a r g e s t o 1694 outpatient charges. Conclusions: Surgical patients who were pharmacologically reversed for NMB and developed a POUR event incurred greater charges than patients without POUR. These findings support the use of NMB reversal agents associated with a lower incidence of POUR.

Leveraging machine learning to develop a postoperative predictive model for postoperative urinary retention following lumbar spine surgery

Introduction

Postoperative urinary retention (POUR) is the inability to urinate after a surgical procedure despite having a full bladder. It is a common complication following lumbar spine surgery which has been extensively linked to increased patient morbidity and hospital costs. This study hopes to development and validate a predictive model for POUR following lumbar spine surgery using patient demographics, surgical and anesthesia variables.

Methods

This is a retrospective observational cohort study of 903 patients who underwent lumbar spine surgery over the period of June 2017 to June 2019 in a tertiary academic medical center. Four hundred and nineteen variables were collected including patient demographics, ICD-10 codes, and intraoperative factors. Least absolute shrinkage and selection operation (LASSO) regression and logistic regression models were compared. A decision tree model was fitted to the optimal model to classify each patient's risk of developing POUR as high, intermediate, or low risk. Predictive performance of POUR was assessed by area under the receiver operating characteristic curve (AUC-ROC).

Results

903 patients were included with average age 60 ± 15 years, body mass index of 30.5 ± 6.4 kg/m2, 476 (53%) male, 785 (87%) white, 446 (49%) involving fusions, with average 2.1 ± 2.0 levels. The incidence of POUR was 235 (26%) with 63 (7%) requiring indwelling catheter placement. A decision tree was constructed with an accuracy of 87.8%.

Conclusion

We present a highly accurate and easy to implement decision tree model which predicts POUR following lumbar spine surgery using preoperative and intraoperative variables.

Risk factors for postoperative urinary retention in fragility hip fracture patients: a prospective study

BACKGROUND

Postoperative urinary retention (POUR) among older patients with hip fractures is common and may result in delayed ambulation, prolonged hospital stays, and urinary tract infections. Although preoperative urinary catheter indwelling and early postoperative removal can prevent perioperative urinary retention, this condition may occur in some patients after catheter removal, which requires urinary catheter re-indwelling or intermittent catheterization. Therefore, this study aims to identify risk factors and develop a screening tool for postoperative urinary retention in patients who have undergone operative treatment for fragility hip fractures subsequent to urinary catheter removal.

METHODS

A prospective cohort study of 145 fragility hip fracture in older patients who were operatively treated between September 2020 and May 2022 was conducted. All patients were evaluated for urine retention after urinary catheter removal using a bladder scan. In addition, factors related to urinary retention were collected and utilized for screening tool development.

RESULTS

Of the included patients, 22 (15.2%) were diagnosed with POUR. A multivariable logistic regression model using a stepwise backward elimination algorithm identified the current use of drugs with anticholinergic effect (OR = 11.9, p = 0.012), international prostate symptom score (IPSS) ≥ 8 (OR = 9.3, p < 0.001), and inability to independently get out of bed within 24 h postoperatively (OR = 6.5, p = 0.051) as risk factors of POUR. The screening tool that has been developed revealed an excellent performance (AuROC = 0.85, 95%CI 0.75 to 0.91) with good calibration and minimal optimism.

CONCLUSIONS

Current use of drugs with anticholinergic effects, IPSS ≥ 8, and inability to independently get out of bed within 24 h postoperatively are significant variables of POUR. For additional external validation, a proposed scoring system for POUR screening was developed.

TRIAL REGISTRATION

The study protocol was retrospectively registered in The Thai Clinical Trials Registry (TCTR20220502001: 2 May 2022).

Postoperative complications after surgery for lumbar spinal stenosis, assessment using two different data sources

PURPOSE

Lumbar spinal stenosis (LSS) is a prevalent disorder, and surgery for LSS is a common procedure. Postoperative complications occur after any surgery and impose costs for society and costs and additional morbidity for patients. Since complications are relatively rare, medical registries of large populations may provide valuable knowledge. However, recording of complications in registries can be incomplete. To better estimate the true prevalence of complications after LSS surgery, we reviewed two different sources of data and recorded complications for a sample of Norwegian LSS patients.

METHODS

474 patients treated surgically for LSS during 2015 and 2016 at four hospitals reported to a national spine registry (NORspine). Postoperative complications were recorded by patients in NORspine, and we cross-referenced complications documented in NORspine with the patients´ electronic patient records (EPR) to re-test the complication rates. We performed descriptive statistics of complication rates using the two different data sources above, and analyzed the association between postoperative complications and clinical outcome with logistic regression.

RESULTS

The mean (95%CI) patient age was 66.3 (65.3-67.2) years, and 254 (53.6%) were females. All patients were treated with decompression, and 51 (10.7%) received an additional fusion during the index surgery. Combining the two data sources, we found a total rate for postoperative complications of 22.4%, the NORspine registry reported a complication rate of 15.6%, and the EPR review resulted in a complication rate of 16.0%. However, the types of complications were inconsistent across the two data sources. According to NORspine, the frequency of reoperation within 90 days was 0.9% and according to EPR 3.4%. The rates of wound infection were for NORspine 3.1% and EPR review 2.1%. There was no association between postoperative complication and patient reported outcome.

CONCLUSION

Postoperative complications occurred in 22% of LSS patients. The frequency of different postoperative complications differed between the two data sources.

Construct validation of machine learning for accurately predicting the risk of postoperative surgical site infection following spine surgery

BACKGROUND

This study aimed to evaluate the risk factors for machine learning (ML) algorithms in predicting postoperative surgical site infection (SSI) following spine surgery.

METHODS

This prospective cohort study included 986 patients who underwent spine surgery at Taizhou People's Hospital Affiliated to Nanjing Medical University from January 2015 to October 2022. Supervised ML algorithms included support vector machine, logistic regression, random forest, XGboost, decision tree, k-nearest neighbour, and naïve Bayes (NB), which were tested and trained to develop a predicting model. The ML model performance was evaluated from the test dataset. We gradually analysed their accuracy, sensitivity, and specificity, as well as the positive predictive value, negative predictive value, and area under the curve.

RESULTS

The rate of SSI was 9.33%. Using a backward stepwise approach, we identified that the remarkable risk factors predicting SSI in the multi-variate Cox regression analysis were age, body mass index, smoking, cerebrospinal fluid leakage, drain duration and pre-operative albumin level. Compared with other ML algorithms, the NB model had the highest performance in seven ML models, with an average area under the curve of 0.95, sensitivity of 0.78, specificity of 0.88, and accuracy of 0.87.

CONCLUSIONS

The NB model in the ML algorithm had excellent calibration and accurately predicted the risk of SSI compared with the existing models, and might serve as an important tool for the early detection and treatment of SSI following spinal infection.

Risk Factors for Postoperative Urinary Retention After Lumbar Fusion Surgery: Anesthetics and Surgical Approach

INTRODUCTION

Postoperative urinary retention (POUR) after lumbar fusion surgery can lead to longer hospital stays and thus increased risk of developing other postoperative complications. Therefore, we aimed to determine the relationship between POUR and (1) surgical approach and (2) anesthetic agents, including sugammadex and glycopyrrolate.

METHODS

After institutional review board approval, L4-S1 single-level lumbar fusion surgeries between 2018 and 2021 were identified. A 3:1 propensity match of patients with POUR to those without was conducted, controlling for patient age, sex, diabetes status, body mass index, smoking status, history of benign prostatic hyperplasia, and the number of levels decompressed. POUR was defined as documented straight catheterization yielding >400 mL. We compared patient demographic, surgical, anesthetic, and postoperative characteristics. A bivariant analysis and backward multivariable stepwise logistic regression analysis ( P -value < 0.200) were performed. Significance was set to P < 0.05.

RESULTS

Of the 899 patients identified, 51 met the criteria for POUR and were matched to 153 patients. No notable differences were observed between groups based on demographic or surgical characteristics. On bivariant analysis, patients who developed POUR were more likely to have been given succinylcholine (13.7% vs. 3.92%, P = 0.020) as an induction agent. The independent predictors of POUR identified by multivariable analysis included the use of succinylcholine {odds ratio (OR), 4.37 (confidence interval [CI], 1.26 to 16.46), P = 0.022} and reduced postoperative activity (OR, 0.99 [CI, 0.993 to 0.999], P = 0.049). Factors protective against POUR included using sugammadex as a reversal agent (OR, 0.38 [CI, 0.17 to 0.82], P = 0.017). The stepwise regression did not identify an anterior surgical approach as a notable predictor of POUR.

CONCLUSION

We demonstrate that sugammadex for anesthesia reversal was protective against POUR while succinylcholine and reduced postoperative activity were associated with the development of POUR. In addition, we found no difference between the anterior or posterior approach to spinal fusion in the development of POUR.

Pre-operative prediction of post-operative urinary retention in lumbar surgery: a prospective validation of machine learning model

PURPOSE

Predicting urinary retention is difficult. The aim of this study is to prospectively validate a previously developed model using machine learning techniques.

METHODS

Patients were recruited from pre-operative clinic. Prediction of urinary retention was completed pre-operatively by 4 individuals and compared to ground truth POUR outcomes. Inter-rater reliability was calculated with intercorrelation coefficient (2,1).

RESULTS

171 patients were included with age 63 ± 14 years, 58.5% (100/171) male, BMI 30.4 ± 5.9 kg/m2, American Society of Anesthesiologists class 2.6 ± 0.5, 1.7 ± 1.0 levels, 56% (96/171) fusions. The observed rate of POUR was 25.7%. The model's performance was found to be 0.663 (0.567-0.759). With a regression model probability cutoff of 0.24 and a neural network cutoff of 0.23, the following predictive power was achieved: specificity 90.6%, sensitivity 22.7%, negative predictive value 77.2%, positive predictive value 45.5%, and accuracy 73.1%. Intercorrelation coefficient for the regression aspect of the model was found to be 0.889 and intercorrelation coefficient for the neural network aspect of the model was found to be 0.874.

CONCLUSIONS

This prospective study confirms performance of the prediction model for POUR developed with retrospective data, showing great correlation. This supports the use of machine learning techniques in the prediction of postoperative complications such as urinary retention.

Effect of systemic lidocaine on postoperative quality of recovery, the gastrointestinal function, inflammatory cytokines of lumbar spinal stenosis surgery: a randomized trial

Surgery is one of the most frequent and effective intervention strategies for lumbar spinal stenosis, however, one-third of patients are not satisfied with postoperative outcomes. It is not clear whether perioperative systemic lidocaine could accelerate the early postoperative quality of recovery in patients undergoing lumbar spinal stenosis surgery. 66 patients were enrolled in this trial. Lidocaine or placebo was administered at a loading dose of 1.5 mg/kg for 10 min and then infused at 2.0 mg/kg/hour till the end of surgery. Continued infusion by postoperative patient-controlled intravenous analgesia with a dose of 40 mg/hour. The primary outcome was the quality of recovery. Secondary outcomes included the time of the patient's first flatus, catheter removal time, underground time from the end of the surgery, pain score, levels of inflammatory factors (IL-6, IL-10, TNF-α), postoperative nausea and vomiting (PONV), sufentanil rescues, patients' satisfaction scores, and complications of lidocaine. Eventually, 56 patients were in the final analysis with similar age, Body Mass Index (BMI), duration of surgery and anesthesia, and median QoR-15 score (a development and Psychometric Evaluation of a Postoperative Quality of Recovery Score). The difference in median QoR-15 score in placebo versus lidocaine patients was statistically significant (IQR, 106 (104-108) versus 114 (108.25-119.25), P < 0.001). The Numeric Rating Scale (NRS) score at the 12th hour, median sufentanil rescue consumption, IL-6, tumor necrosis factor-alpha (TNF-α) of patients treatment with lidocaine were lower. Nevertheless, patients given lidocaine had high satisfaction scores. Suggesting that lidocaine enhanced the postoperative quality of recovery, met early postoperative gastrointestinal function recovery, provided superior pain relief, lessened inflammatory cytokines, etc., indicating it may be a useful intervention to aid recovery following lumbar spinal stenosis surgery.

Construction and validation of a predictive model for postoperative urinary retention after lumbar interbody fusion surgery

BACKGROUND

Postoperative urine retention (POUR) after lumbar interbody fusion surgery may lead to recatheterization and prolonged hospitalization. In this study, a predictive model was constructed and validated. The objective was to provide a nomogram for estimating the risk of POUR and then reducing the incidence.

METHODS

A total of 423 cases of lumbar fusion surgery were included; 65 of these cases developed POUR, an incidence of 15.4%. The dataset is divided into a training set and a validation set according to time. 18 candidate variables were selected. The candidate variables were screened through LASSO regression. The stepwise regression and random forest analysis were then conducted to construct the predictive model and draw a nomogram. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve and the calibration curve were used to evaluate the predictive effect of the model.

RESULTS

The best lambda value in LASSO was 0.025082; according to this, five significant variables were screened, including age, smoking history, surgical method, operative time, and visual analog scale (VAS) score of postoperative low back pain. A predictive model containing four variables was constructed by stepwise regression. The variables included age (β = 0.047, OR = 1.048), smoking history (β = 1.950, OR = 7.031), operative time (β = 0.022, OR = 1.022), and postoperative VAS score of low back pain (β = 2.554, OR = 12.858). A nomogram was drawn based on the results. The AUC of the ROC curve of the training set was 0.891, the validation set was 0.854 in the stepwise regression model. The calibration curves of the training set and validation set are in good agreement with the actual curves, showing that the stepwise regression model has good prediction ability. The AUC of the training set was 0.996, and that of the verification set was 0.856 in the random forest model.

CONCLUSION

This study developed and internally validated a new nomogram and a random forest model for predicting the risk of POUR after lumbar interbody fusion surgery. Both of the nomogram and the random forest model have high accuracy in this study.

Preventing Postoperative Urinary Retention (POUR) in Patients Undergoing Elective Lumbar Surgery: A Quality Improvement Project

BACKGROUND AND OBJECTIVES

Postoperative urinary retention (POUR) is associated with significant morbidity. Our institution's POUR rate was elevated among patients undergoing elective lumbar spinal surgery. We sought to demonstrate that our quality improvement (QI) intervention would significantly lower our POUR rate and length of stay (LOS).

METHODS

A resident-led QI intervention was implemented from October 2017 to 2018 on 422 patients in an academically affiliated community teaching hospital. This consisted of standardized intraoperative indwelling catheter utilization, postoperative catheterization protocol, prophylactic tamsulosin, and early ambulation after surgery. Baseline data on 277 patients were collected retrospectively from October 2015 to September 2016. Primary outcomes were POUR and LOS. The focus, analyze, develop, execute, and evaluate (FADE) model was used. Multivariable analyses were used. P value <.05 was considered significant.

RESULTS

We analyzed 699 patients (277 pre-intervention vs 422 post-intervention). The POUR rate (6.9% vs 2.6%, Δ confidence interval [CI] 1.15-8.08, P = .007) and mean LOS (2.94 ± 1.87 days vs 2.56 ± 2.2 days, Δ CI 0.066-0.68, P = .017) were significantly improved following our intervention. Logistic regression demonstrated that the intervention was independently associated with significantly decreased odds for developing POUR (odds ratio [OR] = 0.38, CI 0.17-0.83, P = .015). Diabetes (OR = 2.25, CI 1.03-4.92, P = .04) and longer surgery duration (OR = 1.006, CI 1.002-1.01, P = .002) were independently associated with increased odds of developing POUR.

CONCLUSIONS

After implementing our POUR QI project for patients undergoing elective lumbar spine surgery, the institutional POUR rate significantly decreased by 4.3% (62% reduction) and LOS, by 0.37 days. We demonstrated that a standardized POUR care bundle was independently associated with a significant decrease in the odds of developing POUR.

Risk Factors for Postoperative Urinary Retention Following Lumbar Spine Surgery: A Review of Current Literature and Meta-Analysis

STUDY DESIGN

Systematic Review and Meta-analysis.

OBJECTIVE

Postoperative urinary retention (POUR) is a common complication following lumbar spine surgery (LSS) and timely recognition is imperative to avoid long-term consequences. The aim of the current meta-analysis was to systematically review the literature in order to identify risk factors associated with POUR after LSS.

METHODS

In accordance with PRISMA guidelines, a systematic review of the literature was performed using Pubmed, EMBASE, and MEDLINE database for articles on POUR following LSS. A meta-analysis was performed comparing patients with and without POUR; and the factors associated with this adverse event were analyzed. The pooled data were reported as mean differences with 95% confidence intervals (CI; P < .05). Heterogeneity among the studies was evaluated using the I2 statistic.

RESULTS

The meta-analysis included 10 studies compromised of 30,300 patients. Based on our analysis, patients who were male, were older in age, underwent instrumented fusion, had diabetes mellitus, coronary artery disease, or benign prostatic hypertrophy had significantly higher risk of developing POUR. Additionally, patients in who developed POUR had significantly longer surgical times and higher volumes of intra-operative fluid administration, as compared with non-POUR patients. The POUR patients also had a significantly higher association with urinary tract infection. Prior surgery, BMI, length of stay, and smoking status did not reveal any statistical association with POUR.

CONCLUSIONS

Risk factors associated with POUR following LSS include male gender, older age, longer surgical times, fusion procedures, larger volumes of intraoperative infusions, and associated comorbidities like DM, CAD, and BPH.

Voluntary Urinary Retention Effects on Cognitive Performance

INTRODUCTION: Aircrew in-flight bladder relief remains an understudied stressor; specifically the effects of withholding urination on flight-relevant cognitive performance. This quasi-experimental study investigated whether voluntary urinary retention over a 3-h period negatively impacted cognitive performance.METHODS: We assessed vigilance using the psychomotor vigilance task (PVT) and measured the P3b event-related potential (ERP) in response to PVT stimuli. We also measured working memory (WM) performance using a change detection task and assessed the contralateral delay activity during the WM task using electroencephalography (EEG). Subjects (N = 29) completed a baseline test on both tasks, following bladder voiding and immediately after consuming 0.75 L of water. Subjects performed tasks at 1, 2, and 3 h post-void and urgency to void one's bladder was assessed regularly. A total of 17 subjects were able to complete the entire study protocol. Repeated-measures ANOVAs assessed changes in PVT and WM outcomes.RESULTS: Reaction time (RT) on the PVT was significantly impaired (5% slower) with longer urinary retention time and showed a 2.5-fold increase in the number of lapses (RT > 500 ms) with increased retention time. Together these results indicate that sustained attention was impaired with increased voluntary urine retention. We did not see significant changes in WM performance with our manipulations. Additionally, neural measures acquired with EEG for both tasks did not show any significant effect.DISCUSSION: As measured with the PVT, sustained attention was impaired during 3 h of voluntary urinary retention, highlighting the need for further development of adequate bladder relief systems in military aviation.Griswold CA, Vento KA, Blacker KJ. Voluntary urinary retention effects on cognitive performance. Aerosp Med Hum Perform. 2023; 94(2):79-85.

Intraoperative bulbocavernosus reflex monitoring in posterior lumbar fusion surgery

OBJECTIVE

To assess the utility of intraoperative bulbocavernosus reflex (BCR) monitoring in posterior lumbar fusion surgery.

METHODS

We retrospectively evaluated 153 patients undergoing posterior lumbar fusion with intraoperative BCR monitoring. Voiding function was assessed at discharge and two follow-ups.

RESULTS

BCR was preserved in 151 patients and completely disappeared in two patients at the end of surgery. For patients in whom BCR was preserved, voiding difficulties at discharge and 1-month and 6-month follow-ups were noted in 16 (10.6%), 9 (6.0%), and 0 (0.0%) patients, respectively. However, patients with BCR loss experienced voiding difficulties at all three time-points. Statistical analysis showed a significant difference in voiding between those with preserved and disappeared BCRs at 6 months postoperatively. BCR disappeared during surgery but recovered before the end of surgery in six patients. Among these patients, one experienced transient voiding difficulties postoperatively but with good recovery. However, the other five patients did not experience postoperative voiding difficulties.

CONCLUSIONS

BCR had low sensitivity for voiding dysfunction at discharge, but had high accuracy at 6-month follow-up examinations. BCR loss was associated with new voiding dysfunction.

SIGNIFICANCE

Intraoperative BCR monitoring is a potentially useful tool for enhancing safety during posterior lumbar fusion by predicting postoperative voiding dysfunction.

Patient outcomes following implementation of an enhanced recovery after surgery pathway for patients with metastatic spine tumors

BACKGROUND

Metastatic spine tumor surgery consists of palliative operations performed on frail patients with multiple medical comorbidities. Enhanced recovery after surgery (ERAS) programs involve an evidence-based, multidisciplinary approach to improve perioperative outcomes. This study presents clinical outcomes of a metastatic spine tumor ERAS pathway implemented at a tertiary cancer center.

METHODS

The metastatic spine tumor ERAS program launched in April 2019, and data from January 2018 to May 2020 were reviewed. Measured outcomes included the following: hospital length of stay (LOS), time to ambulation, urinary catheter duration, time to resumption of diet, intraoperative fluid intake, estimated blood loss (EBL), and intraoperative and postoperative day 0-5 cumulative opioid use (morphine milligram equivalent [MME]).

RESULTS

A total of 390 patients were included in the final analysis: 177 consecutive patients undergoing metastatic spine tumor surgery enrolled in the ERAS program and 213 consecutive pre-ERAS patients. Although the mean case durations were similar in the ERAS and pre-ERAS cohorts (265 vs. 274 min; p = .22), the ERAS cohort had decreased EBL (157 vs. 215 ml; p = .003), decreased postoperative day 0-5 cumulative mean opioid use (178 vs. 396 MME; p < .0001), earlier ambulation (mean, 34 vs. 57 h; p = .0001), earlier discontinuation of urinary catheters (mean, 36 vs. 56 h; p < .001), and shorter LOS (5.4 vs. 7.5 days; p < .0001).

CONCLUSIONS

The implementation of a multidisciplinary ERAS program designed for metastatic spine tumor surgery led to improved clinical quality metrics, including shorter hospitalizations and significant reductions in opioid consumption.

Does tamsulosin decrease postoperative urinary retention in spine surgery? A double-blind, randomized controlled trial

OBJECTIVE

The authors' objective was to determine whether preoperative administration of tamsulosin decreases postoperative urinary retention after spine surgery.

METHODS

In this randomized, double-blind, placebo-controlled clinical trial performed at a single institution between 2016 and 2019, eligible males aged 50 to 85 years were administered tamsulosin or placebo for 5 days prior to elective spine surgery. Patients were excluded if they were taking alpha adrenergic blocking drugs; were allergic to tamsulosin, lactose, or sulfa drugs; had a preexisting indwelling urinary catheter, orthostatic hypotension, history of urological surgery, or renal failure; or were scheduled for cataract surgery within 2 weeks. Screening identified 1051 eligible patients (140 declined participation, 150 did not meet the inclusion criteria, and 151 did not enroll for other reasons). A total of 610 patients were randomly assigned to receive 0.4 mg oral tamsulosin or an identical placebo capsule for 5 days preoperatively and 2 days postoperatively.

RESULTS

A total of 497 patients were included in the final statistical analysis. The overall rate of postoperative urinary retention was 9.7%, and tamsulosin had no observed effect on reducing the rate of postoperative urinary retention as compared with placebo (9.4% vs 9.9%, p = 0.96). There were no significant differences in the reported adverse events between groups. Multivariate logistic regression was performed to model the effects of patient, surgical, and anesthetic factors on postoperative urinary retention, and the study drug remained an insignificant factor.

CONCLUSIONS

This study did not detect an effect of perioperative tamsulosin on reducing the rate of postoperative urinary retention in male patients aged 50 to 85 years who underwent elective spine surgery. This study does not support the routine use of tamsulosin to reduce postoperative urinary retention in patients without a previous prescription. It is unknown if subpopulations exist for which prophylactic tamsulosin may reduce postoperative urinary retention.

Enhanced recovery after surgery (ERAS) protocol in spine surgery

Enhanced recovery after surgery (ERAS) protocols are a set of interventions which are carried out in the preoperative and perioperative period. They are aimed to decrease the harmful effects of surgery on the body and help the patient recover better post-surgery. The effectiveness of ERAS has been well established in various other surgical specialities. Earlier spine surgery was thought to be very complex for application of ERAS protocols. However, this has changed over the last decade with (ERAS) protocols gaining widespread popularity in spine surgery. Initial studies involving ERAS in spine surgery were limited to lumbar spine. However, over the years the horizon of ERAS has expanded to include anterior cervical surgeries, spine deformity, spinal tumors and spine surgery in the elderly. ERAS has been shown to reduce the length of hospital stay, overall hospital costs, opioid consumption in perioperative and postoperative period and to lower complication rates in spine surgery. In this narrative review, we discuss various aspects of ERAS in spine surgery including the benefits of ERAS in spine surgery, the various components of preoperative, intraoperative and postoperative measures of ERAS protocol.

Construction and Validation of a Risk Prediction Model for Postoperative Urinary Retention in Lung Cancer Patients

Indwelling catheter is a routine procedure in surgical patients. Studies have shown that prolonged indwelling urinary catheterization increases the risk of postoperative urinary tract infection. Although early removal of the urinary catheter after operation can reduce the risk of postoperative urinary symptoms and tract infections, it may lead to postoperative anesthetic dysuria. Therefore, this study investigates the urinary retention and related risk factors in patients after thoracoscopic lobectomy under general anesthesia. The clinical data of 214 patients who underwent thoracoscopic lobectomy in the Department of Thoracic Surgery of a tertiary class A cancer hospital in Beijing from July 2020 to April 2021 were collected. A risk prediction model was established by logistic regression analysis, and the prediction effect was determined using the area under the receiver operating characteristic (ROC) curve. The incidence of indwelling catheter after thoracoscopic lobectomy was 44.8% (96/214). Sex (OR = 21.102, 95% CI: 2.906-153.239, P=0.003), perception of shame (OR = 74.256, 95% CI: 6.171-893.475, P=0.001), age (OR = 1.095, 95% CI: 1.014-1.182, P=0.021), and bed rest time (OR = 1.598, 95% CI: 1.263-2.023, P < 0.021) were the factors influencing urinary retention after thoracoscopic lobectomy. This model can effectively predict the occurrence of postoperative urinary retention in patients with lung cancer and help medical staff to intervene effectively before the onset of urinary retention, which provides reference for preventive treatment and nursing intervention.

Interdisciplinary Surgical Treatments and Long-Term Outcomes of Lumbar Spinal Tumors With Retroperitoneal Involvements: A Retrospective Case Series Study

Purpose

Surgical treatments are technically challenging for lumbar spinal tumor (LST) with extensive retroperitoneal involvements. Our study aimed to report the experience and outcomes concerning interdisciplinary surgical collaborations in managing such LSTs.

Patients and Methods

Nine patients underwent interdisciplinary surgical treatments which were performed by specialists, namely, spinal, vascular, and urinary surgeries. Data on clinical characteristics were collected, and the Visual Analogue Scale (VAS) and the Japanese Orthopaedic Association Score (JOAS) were used in the evaluation before and after surgery. The postoperative complications and the long-term outcomes were reported as well.

Results

The interdisciplinary work included double J catheter indwelling (n = 9), nephrostomy (n = 5), replacement of the common iliac vein (n = 2), abdominal aorta repair (n = 3), and vital vessel repair (n = 8). The early-stage complications included complaints of moderate low back pain and slight implant shift (n = 1, 11.1%) and tardive ureterodialysis (n = 1, 11.1%). The 3- and 5-year disease-free survival rates were 76.2 ± 14.8 and 50.8 ± 23.0%, respectively, during the mean follow-up of 34.6 ± 17.9 months (range, 9.5–68.7). Besides this, more blood loss was associated with recurrent and metastatic tumor status (p = 0.043) and surgery time >5 h (p = 0.023). Remarkable pain relief and favorable quality of life were achieved based on the postoperative VAS (3.3 ± 0.9, p < 0.001) and JOAS (16.6 ± 0.5, p < 0.001).

Conclusions

The treatments of LSTs with wide-range retroperitoneal involvements require interdisciplinary surgical collaborations to lower the risks and improve the long-term outcomes. High-quality prospective cohort studies with large samples are warranted to establish general surgical protocols in managing LSTs with extensive retroperitoneal involvements.

Preoperative prediction of postoperative urinary retention in lumbar surgery: a comparison of regression to multilayer neural network

OBJECTIVE

Postoperative urinary retention (POUR) is a common complication after spine surgery and is associated with prolongation of hospital stay, increased hospital cost, increased rate of urinary tract infection, bladder overdistention, and autonomic dysregulation. POUR incidence following spine surgery ranges between 5.6% and 38%; no reliable prediction tool to identify those at higher risk is available, and that constitutes an important gap in the literature. The objective of this study was to develop and validate a preoperative risk model to predict the occurrence of POUR following routine elective spine surgery.

METHODS

The authors conducted a retrospective chart review of consecutive adults who underwent lumbar spine surgery between June 1, 2017, and June 1, 2019. Patient characteristics, preexisting ICD-10 codes, preoperative pain and opioid use, preoperative alpha-1 blocker use, details of surgical planning, development of POUR, and management strategies were abstracted from electronic medical records. A binomial logistic model and a multilayer perceptron (MLP) were optimized using training and validation sets. The models' performance was then evaluated on model-naïve patients (not a part of either cohort). The models were then stacked to take advantage of each model's strengths and to avoid their weaknesses. Four additional models were developed from previously published models adjusted to include only relevant factors (i.e., factors known preoperatively and applied to the lumbar spine).

RESULTS

Overall, 891 patients were included in the cohort, with a mean of 59.6 ± 15.5 years of age, 52.7% male, BMI 30.4 ± 6.4, American Society of Anesthesiologists class 2.8 ± 0.6, and a mean of 5.6 ± 5.7 comorbidities. The rate of POUR was found to be 25.9%. The two models were comparable, with an area under the curve (AUC) of 0.737 for the regression model and 0.735 for the neural network. By combining the two models, an AUC of 0.753 was achieved. With a regression model probability cutoff of 0.24 and a neural network cutoff of 0.23, maximal sensitivity and specificity were achieved, with specificity 68.2%, sensitivity 72.9%, negative predictive value 88.2%, and positive predictive value 43.4%. Both models individually outperformed previously published models (AUC 0.516-0.645) when applied to the current data set.

CONCLUSIONS

This predictive model can be a powerful preoperative tool in predicting patients who will be likely to develop POUR. By using a combination of regression and neural network modeling, good sensitivity, specificity, and NPV are achieved.

Postoperative Urinary Retention Following Thoracolumbosacral Spinal Fusion: Prevalence, Risk Factors, and Outcomes

Objective

Postoperative urinary retention (POUR) is an often-underestimated common complication following spine surgery, and it is essential to avoid its untoward long-term consequences. Besides, a dilemma exists regarding the appropriate timing for the postoperative removal of indwelling catheter (IDC). Hence, we aim to describe the prevalence, risk factors, and outcomes of POUR and also come up with recommendations for the removal of IDC.

Methods

Electronic records of patients who underwent elective thoracolumbosacral spinal fusion surgery from January 2017 to December 2019 were retrospectively reviewed. Excluded were those who underwent fusion for indications such as trauma, cauda equina syndrome, infection, and malignancy. Both surgery-related and patient-related risk factors were tabulated, and their association with the likely development of POUR was assessed by univariate and multivariate analysis.

Results

One hundred sixty-eight patients (median age=64.1 years; 58.9% female) were included, with the incidence of POUR being 7.8%. Our findings suggest surgery-related factors, both intra- and postoperative, including operating time (p=0.008), anesthetic time (p=0.005), number of fusion levels (p<0.001), mobilization status prior to trial off catheter (TOC; p=0.021), and TOC timing (p=0.029) may have an association with POUR. In addition, patient-related factors, including the use of beta-blockers (p=0.020) and pre-operative mobility status (p<0.001), may also be associated with the likely development of POUR.

Conclusion

POUR seems to be a frequent complication following thoracolumbosacral spinal fusion surgery, which was found to have an association with some surgery-related and patient-related factors. While most of these factors are non-modifiable, certain modifiable risk factors provide the surgeon an opportunity to prevent POUR. Considering these factors, we recommend appropriate and timely mobilization of the patient prior to removal of IDC, which is to be performed preferably in the daytime.

Risk factors for postoperative urinary retention following elective spine surgery: a meta-analysis

BACKGROUND CONTEXT

Limited studies have investigated risk factors for postoperative urinary retention (POUR) following elective spine surgery. Furthermore, some discrepancies have been found in the results of existing observational studies.

PURPOSE

This study aimed to review the available literature on risk factors associated with POUR following elective spine surgery.

STUDY DESIGN

A systematic review with meta-analysis was performed.

PATIENT SAMPLE

A total of 31,251 patients (POUR=2,858, no POUR=28,393) were included in the meta-analysis.

OUTCOME MEASURES

Demographics, type of elective spine surgery, country, definition of POUR, and potential risk factors for POUR were evaluated.

METHODS

The Cochrane Library, Embase, and Medline electronic databases were searched to identify relevant studies. Binary outcomes were reported as odds ratio (OR). Weighted mean differences (WMD) or standardized mean differences (SMD), with 95% confidence intervals (CI), were used for meta-analysis of continuous outcomes.

RESULTS

Eleven studies (2 prospective and 9 retrospective) were included in the analysis. Patients with POUR were older than those without POUR (WMD, 7.13; 95% CI, 4.50-9.76). Male patients were found to have an increased risk of POUR (OR, 1.31; 95% CI, 1.04-1.64). The following variables were also identified as significant risk factors for POUR: benign prostatic hyperplasia (BPH; OR, 3.79; 95% CI, 1.89-7.62), diabetes mellitus (DM; OR, 1.50; 95% CI, 1.17-1.93), and previous urinary tract infection (UTI; OR, 1.70; 95% CI, 1.28-2.24). Moreover, longer operative time (WMD, 19.88; 95% CI, 5.01-34.75) and increased intraoperative fluid support (SMD, 0.37; 95% CI, 0.23-0.52) were observed in patients with POUR. In contrast, spine surgical procedures involving fewer levels (OR, 0.75; 95% CI, 0.65-0.86), and ambulation on the same day as surgery (OR, 0.65; 95% CI, 0.52-0.81) were associated with a decreased risk of POUR.

CONCLUSIONS

Based on our meta-analysis, older age, male gender, BPH, DM, and a history of UTI are risk factors for POUR following elective spine surgery. We also found that longer operative time and increased intravenous fluid support would increase the risk of POUR. Additionally, multi-level spine surgery may have a negative effect on postoperative voiding.

Predictors of postoperative urinary retention after posterior spinal fusion for adolescent idiopathic scoliosis

PURPOSE

To determine predictors for postoperative urinary retention in adolescents undergoing posterior spinal fusion for idiopathic scoliosis. Postoperative urinary retention affects almost every third adolescent after spinal fusion for idiopathic scoliosis. There are limited data regarding the risk factors of postoperative urinary retention in this patient group.

METHODS

A retrospective study with prospectively collected urinary retention data from paediatric spine register with 159 consecutive patients (114 females, mean age 15.6 years, range 10-21 years) undergoing pedicle screw instrumentation for adolescent idiopathic scoliosis at a university hospital between May 2010 and April 2020. Postoperative urinary retention was defined as an inability to void after catheter removal and documented residual over 300 mL as confirmed using an ultrasound or by catheterization.

RESULTS

Postoperative urinary retention was diagnosed in 33% (53 of 159) of the patients during hospital stay. Opioid amount on the day of catheter removal (OR 6.74 [95% CI: 2.47, 18.36], p < 0.001), male gender (OR 2.26 [95% CI: 1.01, 5.05], p = 0.048), and increasing weight (OR 1.04 [95% CI: 1.01, 1.07], p = 0.014) were associated with postoperative urinary retention. Mean opioid consumption on the day of catheter removal was 0.81 mg/kg (95% CI: 0.66, 0.96) in the retention group vs 0.57 mg/kg (95% CI: 0.51, 0.64) in the non-retention group, p < 0.001.

CONCLUSIONS

Higher total opioid consumption, opioid amount on the day of catheter removal, higher weight, and male gender increases the risk of postoperative urinary retention in adolescents with idiopathic scoliosis undergoing posterior spinal fusion.

A prediction model for postoperative urinary retention after thoracic surgery

Background

Urinary retention remains a frequent postoperative complication, associated with patient discomfort and delayed discharge following general thoracic surgery (GTS). We aimed to develop and prospectively validate a predictive model of postoperative urinary retention (POUR) among GTS patients.

Methods

We retrospectively developed a predictive model using data from the Society of Thoracic Surgeons GTS Database at our institution. The patient study cohort included adults undergoing elective in-patient surgical procedures without a history of renal failure or Foley catheter on entry to the recovery suite (August 2013 to March 2017). Multivariable logistic regression models identified factors associated with urinary retention, and a nomogram to aid medical decision making was developed. The predictive model was validated in a cohort of GTS patients between April 2017 and November 2018 using receiver operating characteristic (ROC) analysis.

Results

The predictive model was developed from 1484 GTS patients, 284 of whom (19%) experienced postoperative urinary retention within 24 hours of the operation. Risk factors for POUR included older age, male sex, higher preoperative creatinine, chronic obstructive pulmonary disease, primary diagnosis, primary procedure, and use of postoperative patient-controlled analgesia. A logistic nomogram for estimating the risk of POUR was created and validated in 646 patients, 65 of whom (10%) had urinary retention. The ROC curves of development and validation models had similar favorable c-statistics (0.77 vs 0.72; P > .05).

Conclusions

Postoperative urinary retention occurs in nearly 20% of patients undergoing major GTS. Using a validated predictive model may help by targeting certain patients with prophylactic measures to prevent this complication.

Incidence and Risk Factors for Postoperative Urinary Retention Following Lumbar Spine Fusion

STUDY DESIGN

This was a prospective cohort study (observational-retrospective chart review).

OBJECTIVE

The objective of this study was to determine clinical rates and correlations of postoperative urinary retention (POUR) in elective spine decompression and fusion procedures.

SUMMARY OF BACKGROUND DATA

POUR is a common postoperative complication that often has a major adverse impact on a patient's recovery from elective lumbar spine surgery. The etiology of POUR in most cases is unknown. Patients undergoing lumbar spine surgery are considered to be at increased risk for POUR due to prone positioning during surgery and intraoperative cauda equina nerve root manipulation. Current studies reporting on POUR after elective spine surgery provide limited insight regarding risk factors and effective prevention strategies for this at-risk population. The purpose of this study is to identify risk factors for POUR after elective lumbar spine surgery and strategies for reducing its incidence.

MATERIALS AND METHODS

Two hundred consecutive patients aged 50 years or older undergoing combined lumbar decompression and fusion procedures over a 5-month period at a single institution were prospectively observed. Demographic and clinical data were prospectively recorded, including: medical history, surgical data, medications administered, complications, and postoperative hospital course. Factors correlating with POUR through a univariate analysis with P≤0.20 were considered for multivariate analysis.

RESULTS

POUR occurred in 19 of 200 patients. Those with POUR were more likely to be male (20% vs. 4%, odds ratio=6.2). Administration of scopolamine (P=0.02), neostigmine (P=0.01), and the total number of levels operated on (P=0.02) were found to be independent risk factors for the development of POUR. Length of surgery, surgical level, the performance of an interbody fusion did not have a bearing on the development of POUR (P>0.05).

DISCUSSION

We describe a single institution's experience of POUR incidence in 200 consecutive patients aged 50 years or older undergoing single or multilevel lumbar spine fusion procedures by 1 of 4 surgeons. Specific demographic and clinical risk factors were identified and a codified classification for POUR in a surgical population is presented.The results of this study will help clinicians appropriately counsel patients undergoing elective lumbar fusion about the potential development of POUR. The perioperative administration of scopolamine and neostigmine should be cautiously considered in men over 50 years of age due to the increased POUR risk.

CONCLUSIONS

Perioperative scopolamine and neostigmine administration in men over 50 should be avoided when possible to minimize the risk of POUR.

LEVEL OF EVIDENCE

Level III.

Consensus statement for perioperative care in lumbar spinal fusion: Enhanced Recovery After Surgery (ERAS®) Society recommendations

BACKGROUND

Enhanced Recovery After Surgery (ERAS) evidence-based protocols for perioperative care have led to improvements in outcomes in numerous surgical areas, through multimodal optimization of patient pathway, reduction of complications, improved patient experience and reduction in the length of stay. ERAS represent a relatively new paradigm in spine surgery.

PURPOSE

This multidisciplinary consensus review summarizes the literature and proposes recommendations for the perioperative care of patients undergoing lumbar fusion surgery with an ERAS program.

STUDY DESIGN

This is a review article.

METHODS

Under the impetus of the ERAS® society, a multidisciplinary guideline development group was constituted by bringing together international experts involved in the practice of ERAS and spine surgery. This group identified 22 ERAS items for lumbar fusion. A systematic search in the English language was performed in MEDLINE, Embase, and Cochrane Central Register of Controlled Trials. Systematic reviews, randomized controlled trials, and cohort studies were included, and the evidence was graded according to the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system. Consensus recommendation was reached by the group after a critical appraisal of the literature.

RESULTS

Two hundred fifty-six articles were included to develop the consensus statements for 22 ERAS items; one ERAS item (prehabilitation) was excluded from the final summary due to very poor quality and conflicting evidence in lumbar spinal fusion. From these remaining 21 ERAS items, 28 recommendations were included. All recommendations on ERAS protocol items are based on the best available evidence. These included nine preoperative, eleven intraoperative, and six postoperative recommendations. They span topics from preoperative patient education and nutritional evaluation, intraoperative anesthetic and surgical techniques, and postoperative multimodal analgesic strategies. The level of evidence for the use of each recommendation is presented.

CONCLUSION

Based on the best evidence available for each ERAS item within the multidisciplinary perioperative care pathways, the ERAS® Society presents this comprehensive consensus review for perioperative care in lumbar fusion.

Evaluation of Risk Factors for Postoperative Urinary Retention in Elective Thoracolumbar Spinal Fusion Patients

STUDY DESIGN

Retrospective case series.

OBJECTIVES

Postoperative urinary retention (POUR) represents a common postoperative complication of all elective surgeries. The aim of this study was to identify demographic, comorbid, and surgical factors risk factors for POUR in patients who underwent elective thoracolumbar spine fusion.

METHODS

Following institutional review board approval, patients who underwent elective primary or revision thoracic and lumbar instrumented spinal fusion in a 2-year period in tertiary and academic institution were reviewed. Sex, age, BMI, preoperative diagnosis, comorbid conditions, benign prostatic hyperplasia, diabetes, primary or revision surgery status, narcotic use, and operative factors were collected and analyzed between patients with and without POUR.

RESULTS

Of the 217 patients reviewed, 54 (24.9%) developed POUR. The average age for a patient with POUR was 67 ± 9, as opposed to 59 ± 10 for those without (P < .0001). Single-level fusions were associated with a 0% incidence of POUR, compared with 54.5% in 6 or more levels. The average hospital stay was increased by 1 day for those who had POUR (5.8 ± 3.3 vs 4.9 ± 3.9 days). There was no significant association with other demographic variables, comorbid conditions, or surgical factors.

CONCLUSIONS

POUR was a common complication in our patient cohort, with an incidence of 24.9%. Our findings demonstrate that patients who developed POUR are significantly older and have larger constructs. Patients who developed POUR also had longer in-hospital stays. Although our study supports other findings in the spine literature, more prospective data is needed to define diagnostic criteria of POUR as well as its management.

Efficacy of intraoperative bulbocavernosus reflex monitoring for the prediction of postoperative voiding function in adult patients with lumbosacral spinal tumor

Lumbosacral spinal tumor surgery is associated with a relatively high risk of postoperative voiding dysfunction. This study aimed to investigate the correlation between intraoperative bulbocavernosus reflex (BCR) changes and postoperative voiding function in adult patients with lumbosacral spinal tumors. We retrospectively reviewed 63 patients who underwent intradural conus and cauda equina tumor surgeries with intraoperative BCR monitoring. We evaluated patients' voiding functions for 6 months postoperatively. BCR was maintained in 60 patients and disappeared in 3 patients at the end of the surgery. Among the patients in whom BCR was maintained, examinations conducted at discharge and at 1- and 6-month follow-ups revealed that 7 (11.7%), 4 (6.7%), and zero (0.0%) patients experienced voiding difficulty, respectively. However, all 3 (100%) patients without BCR experienced voiding difficulty at the three corresponding follow-ups. Data analysis indicated no significant difference in voiding between the maintained and disappeared BCR groups 6-months postoperatively. The sensitivity, specificity, positive predictive, and negative predictive values of intraoperative BCR monitoring for detecting new and worsening difficulty in voiding were all 100% 6 months postoperatively. Our results shows that intraoperative BCR monitoring is a reliable predictor of voiding function following surgery in adult patients undergoing lumbosacral spinal tumor surgery. Intraoperative BCR monitoring can be useful for assessing and monitoring the integrity of the voiding function during lumbosacral spinal tumor surgery.

Urinary Tract Infection after Elective Spine Surgery: Timing, Predictive Factors, and Outcomes

STUDY DESIGN

Retrospective review of prospectively collected data.

OBJECTIVE

The aim of this study was to investigate risk factors associated with the timing of urinary tract infection (UTI) after elective spine surgery, and to determine whether postoperative UTI timing affects short-term outcomes.

SUMMARY OF BACKGROUND DATA

Urinary tract infection (UTI) is a common post-surgical complication; however, the predominant timing, location, and potential differential effects have not been carefully studied.

METHODS

We analyzed elective spine surgery patients from 2012 to 2018 in the ACS National Surgical Quality Improvement Program (NSQIP). We grouped patients with postoperative UTI by day of onset relative to discharge, to create cohorts of patients who developed inpatient UTI and post-discharge UTI. We compared both UTI cohorts with a control (no UTI) population and with each other to identify differences in baseline characteristics including demographic, comorbidity and operative factors. We performed multivariate logistic regression to identify predictors of UTI in each cohort and to assess adjusted risks of poor outcomes associated with UTI timing.

RESULTS

A total of 289,121 patients met inclusion criteria and 0.88% developed UTI (n = 2553). Only 31.6% of UTIs occurred before discharge (n = 806), with 68.4% occurring after discharge (n = 1747). The inpatient UTI cohort had significantly longer operative time, more fusion procedures, more posterior procedures, and more procedures involving the lumbar levels than the post-discharge cohort. Predictors of inpatient UTI included procedure type, spine region, and approach. Predictors of post-discharge UTI included length-of-stay and discharge destination. Both UTI cohorts were significantly associated with sepsis; however, post-discharge UTI carried a higher odds (adjusted odds ratio [aOR] = 24.90, 95% confidence interval [CI] = 21.05-29.45, P < 0.001 vs. aOR = 14.31, 95% CI = 11.09-18.45, P < 0.001). Inpatient UTI was not associated with 30-day readmission, although post-discharge UTI was (aOR = 8.23, 95% CI = 7.36-9.20, P < 0.001). Conversely, inpatient UTI was associated with increased odds of 30-day mortality (aOR = 3.23, 95% CI = 1.62-6.41, P = 0.001), but post-discharge UTI was not.

CONCLUSION

Predictive factors and outcomes differ based on timing of UTI after elective spine surgery. Before discharge, procedure -specific details predict UTI, but after discharge they do not. These findings suggest that traditional thinking about UTI prevention may need modification.Level of Evidence: 3.

Risk Factors Associated With Development of Urinary Retention Following Posterior Lumbar Spinal Fusion: Special Attention to the Use of Glycopyrrolate in Anesthesia Reversal

STUDY DESIGN

The study is designed as a retrospective cohort study.

OBJECTIVE

The aim of this study was to identify modifiable and nonmodifiable risk factors of postoperative urinary retention in spine surgery patients.

SUMMARY OF BACKGROUND DATA

Postoperative urinary retention is a common complication in patients undergoing operative procedures requiring anesthesia. Current studies have shown significant risk factors for postoperative urinary retention, but most are nonmodifiable and subsequently of limited usefulness in preventing this complication. Several new studies have shown possible modifiable risk factors, but current data are inconsistent in terms of their statistical significance.

METHODS

A total of 814 consecutive patients who underwent open posterior lumbar laminectomy and fusion were included in the retrospective cohort study. Pre, intra-, and postoperative characteristics were collected in all patients to identify risk factors for postoperative urinary retention.

RESULTS

Glycopyrrolate use (odds ratio [OR] 2.60; P = 0.001), decreased body mass index (OR 0.96; P = 0.018), previous diagnosis of benign prostate hyperplasia (OR 3.34; P ≤ 0.001), and postoperative urinary tract infection (OR 5.60, P = 0.005) were associated with postoperative urinary retention. Previous history of lumbar spine surgery (OR 0.55; P = 0.019) was associated with decreased rates of postoperative urinary retention.

CONCLUSION

Glycopyrrolate use, benign prostate hyperplasia, and postoperative urinary tract infection were independent risk factors for postoperative urinary retention. The use of glycopyrrolate is a potentially modifiable risk factor for postoperative urinary retention.Level of Evidence: 3.

Spinal surgery and urinary retention: A review of the literature

Objective:

Postoperative urinary retention is a common complication for patients recovering from general anesthesia or invasive surgery near the spinal column. However, no study has systematically reviewed the incidence of postoperative urinary retention for spinal surgeries performed at the cervical, thoracic, or lumbar spinal regions. In this review, we critically analyze and summarize the known literature on the incidence and risk factors associated with postoperative urinary retention after spinal surgery.

Methods:

A comprehensive literature review was performed at the end of September 2019 within the PubMed database.

Results:

The average incidence of postoperative urinary retention from nine of the 10 studies was 17.2% with one paper that did not report on postoperative urinary retention incidence. Furthermore, age, male gender, location and history of spinal surgery, duration of surgery, benign prostatic hypertrophy, and Foley catheter were reported as major risk factors for postoperative urinary retention and spinal surgery.

Conclusion:

Overall, spinal cord and postoperative urinary retention remains a poorly understood area requiring further investigation into the incidence, risk factors, and surgical methods influence postoperative urinary retention and post-operative outcomes. We believe an overview of such data can help revise guidelines for the management of postoperative urinary retention and raise awareness of its prevalence in elderly patients undergoing spinal surgery.

Level of evidence:

Not applicable for this multicentre audit.

Intraoperative Fluid Management in Patients Undergoing Spine Surgery: A Narrative Review

Fluid management has been widely recognized as an important component of the perioperative care in patients undergoing major procedures including spine surgeries. Patient- and surgery-related factors such as age, length of the surgery, massive intraoperative blood loss, and prone positioning, may impact the intraoperative administration of fluids. In addition, the type of fluid administered may also affect post-operative outcomes. Published literature describing intraoperative fluid management in patients undergoing major spine surgeries is limited and remains controversial. Therefore, we reviewed current literature on intraoperative fluid management and its association with post-operative complications in spine surgery.

Does minimally invasive spine surgery reduce the rate of perioperative medical complications? A retrospective single-center experience of 1435 degenerative lumbar spine surgeries

PURPOSE

It is unclear if minimally invasive techniques reduce the rate of perioperative complications when compared to traditional open approaches to the lumbar spine. Our aim was to evaluate perioperative complications in patients that underwent MIS and conventional open techniques for degenerative lumbar pathology.

METHODS

A retrospective review of a prospectively collected database identified 1435 patients that underwent surgery for degenerative lumbar pathology from January 2013-2016. We evaluated the rates of deep vein thrombosis, pulmonary embolism, urinary tract infection, and pneumonia. Groups were analyzed based on decompression alone as compared with decompression and fusion for both MIS and traditional open techniques.

RESULTS

Patients that underwent traditional open lumbar decompression surgery were more likely to develop a DVT (P = .01) than those undergoing MIS decompression. There was no significant difference in rates of PE (P = .99), UTI (P = .24), or pneumonia (P = .56). Patients that underwent traditional open lumbar fusion surgery compared to MIS fusion were also more likely to have a PE (P = .03). There was no significant difference in rates of DVT (P = .22), UTI (P = .43), or pneumonia (P = .24).

CONCLUSION

Minimally invasive spinal surgery was found to reduce the rate of DVT for decompression surgeries and reduce the rate of PE for fusion surgeries.

Incidence, prognosis, and risk factors for bladder and bowel dysfunction due to incidental dural tears in lumbar microendoscopic surgery

BACKGROUND CONTEXT

Despite the common occurrence of incidental dural tears, the incidence and prognosis of bladder and bowel dysfunction (BBD) due to incidental dural tears in lumbar spinal surgery are not well known because of the lack of reported cases.

PURPOSE

To analyze the incidence, prognosis, and risk factors for BBD after lumbar microendoscopic surgery with or without incidental dural tears.

STUDY DESIGN/SETTING

A retrospective cohort study.

PATIENT SAMPLE

We analyzed 2,421 patients who underwent lumbar microendoscopic surgery and investigated patients with BBD after an incidental durotomy during surgery.

OUTCOME MEASURES

Patients were divided into three groups on the basis of dysuria and defecation disorders: severe BBD, mild BBD, and no BBD. The post void residual volumes before and after surgery were compared using an ultrasound bladder scanner or bladder catheterization after confirmation of urination. Bowel dysfunction was evaluated by subjective symptomatic deterioration and the increase in the frequency and duration of postoperative medical care.

METHODS

Risk factors for BBD were analyzed using surgical video documentation to determine the dural tear site and cauda equina exposure from the dural sac. Patients with BBD were prospectively followed up for prognosis determination. The chi-square test was used to compare the incidence of BBD between patients with dural tears and those without. Propensity score-adjusted logistic regression analysis was performed to evaluate the effects of various factors on the incidence of postoperative BBD.

RESULTS

The incidence of dural tears was 6.9% (168/2,421). The overall incidence of BBD was 3.0% (73/2,421), while the incidences of BBD (mild+severe BBD) and severe BBD due to incidental dural tears were 1.2% (30/2,421) and 0.8% (20/2,421), respectively. The incidence of BBD in patients with dural tears and those without tears was 17.9% [30/168] and 1.9% [43/2,253; p<.001]), respectively. BBD rates at 1 week, 1 month, 3 months, 6 months, and 1 year after surgery were 64.0%, 44.0%, 40.0%, 28.0%, and 13.6%, respectively. Logistic regression analysis revealed that the male sex (odds ratio [OR], 4.20), dural tears in the central area (OR, 10.15), and exposure of the cauda equina (OR, 51.04) were significant risk factors.

CONCLUSIONS

The incidence of dural tears in lumbar microendoscopic surgeries are associated with an increased incidence of BBD. The recovery rate for BBD due to incidental dural tears is generally good; however, some patients experience long-term symptoms. Clinicians should be aware that incidental dural tears with cauda equina exposure can increase the risk of BBD.

Considering healthcare value and associated risk factors with postoperative urinary retention after elective laminectomy

BACKGROUND

Mitigating common complications such as postoperative urinary retention (POUR) following elective spine surgery is prudent. Identifying patients at risk for POUR and recognizing associated factors, to avoid a more complicated postoperative episode should be a priority and easily achievable. Understanding the financial burden of complications, such as POUR, is also important for value-based healthcare, not only for providers, but for employers and payors as well.

PURPOSE

The purpose of this study is to examine patient and surgical factors that may lead to increased risk for POUR and its associated cost following elective lumbar laminectomies.

STUDY DESIGN/SETTING

This is a retrospective study of the incidence of postoperative urinary retention after elective one- and two-level primary lumbar laminectomies.

PATIENT SAMPLE

We followed patients undergoing one- and two-level primary elective lumbar laminectomies performed between April 2014 and December 2016.

OUTCOME MEASURES

Patient factors included age, gender, body-mass index, and comorbidities. Surgical factors included surgical time, intraoperative fluid volume requirements, anesthesia type, and surgical levels involved. Other outcome variables included length of stay, discharge disposition, 30-day all-cause readmissions and emergency department visits, 90-day complications, and variable direct costs.

METHODS

The incidence of POUR was evaluated and compared with patient and surgical factors and cost-specific variables to identify correlations and potential risk for POUR after one- and two-level primary lumbar laminectomies.

RESULTS

Analysis included 333 patients - 203 one-level laminectomies and 130 two-level laminectomies. The overall incidence of POUR was 17.4%. Age, male gender, and history of urinary retention were significantly associated with POUR. There was a significantly increased risk of POUR with increased surgical time, but not with anesthesia type. There were also no significant differences in body-mass index, other study comorbidities, intraoperative fluid requirements, readmission, emergency department visit, and complication rates between groups. On average, patients with POUR had a significantly longer length of stay than patients without POUR. In addition, more POUR patients were discharged to acute rehabilitation facilities and had higher average variable direct cost compared tonon-POUR patients.

CONCLUSIONS

POUR is a significant risk after elective laminectomy. This study supports several widely accepted beliefs regarding POUR risk, while challenging others. It also highlights the burden of POUR development after surgery. At our institution, we developed a protocol supported by these findings.

A machine learning approach for predictive models of adverse events following spine surgery

BACKGROUND

Rates of adverse events following spine surgery vary widely by patient-, diagnosis-, and procedure-related factors. It is critical to understand the expected rates of complications and to be able to implement targeted efforts at limiting these events.

PURPOSE

To develop and evaluate a set of predictive models for common adverse events after spine surgery.

STUDY DESIGN

A retrospective cohort study.

PATIENT SAMPLES

We extracted 345,510 patients from the Truven MarketScan (MKS) and MarketScan Medicaid Databases and 760,724 patients from the Centers for Medicare and Medicaid Services (CMS) Medicare database who underwent spine surgeries between 2009 and 2013.

OUTCOME MEASURES

Overall adverse event (AE) occurrence and types of AE occurrence during the 30-day postoperative follow-up.

METHODS

We applied a least absolute shrinkage and selection operator regularization method and a logistic regression approach for predicting the risks of an overall AE and the top six most commonly observed AEs. Predictors included patient demographics, location of the spine procedure, comorbidities, type of surgery performed, and preoperative diagnosis.

RESULTS

The median ages of MKS and CMS patients were 49 years and 69, respectively. The most frequent individual AE was a cardiac dysfunction in CMS (10.6%) patients and a pulmonary complication (4.7%) in MKS. The area under the curve (AUC) of a prediction model for an overall AE was 0.7. Among the six individual prediction models, the model for predicting the risk of a pulmonary complication showed the greatest accuracy (AUC 0.76), and the range of AUC for these six models was 0.7 and 0.76. Medicaid status was one of the most important factors in predicting the occurrences of AEs; Medicaid recipients had increased odds of AEs by 20%-60% compared with non-Medicaid patients (odds ratios 1.28-1.6; p<10^-10). Logistic regression showed higher AUCs than least absolute shrinkage and selection operator across these different models.

CONCLUSIONS

We present a set of predictive models for AEs following spine surgery that account for patient-, diagnosis-, and procedure-related factors which can contribute to patient-counseling, accurate risk adjustment, and accurate quality metrics.

Would early removal of indwelling catheter effectively prevent urinary retention after hip fracture surgery in elderly patients?

BACKGROUND

This study aimed to investigate the incidence and risk factors of postoperative urinary retention (POUR) among elderly patients who underwent hip fracture surgery and to evaluate the effect of indwelling catheterization on the occurrence of POUR.

MATERIALS AND METHODS

From January 2012 to January 2015, consecutive patients aged over 70 years who underwent hip fracture surgery were enrolled in this study. All patients underwent indwelling catheterization due to voiding difficulty upon admission. Demographic data, perioperative variables, and postoperative duration of patient-controlled analgesia and indwelling catheterization, postoperative complications, and mortality were collected. The incidence of POUR was investigated, and the risk factors related to POUR were analyzed using a logistic regression analysis. The cutoff value for the timing of catheter removal was determined using receiver operating characteristic (ROC) curve analysis.

RESULTS

POUR developed in 68 patients (31.8%) of the 214 patients. Of these, 24 (35.3%) were male. The indwelling catheter was left in place for an average of 3.4 days (range, 0-7 days) postoperatively. A significant difference was noted in gender and duration of indwelling catheterization between patients with POUR and without. The cutoff value for the timing of catheter removal as determined by ROC curve analysis was 3.5 postoperative day with 51.4% sensitivity and 71.5% specificity. Multiple logistic regression revealed that the duration of the indwelling catheter [odds ratios (OR), 0.31; p = 0.016)] and male gender (OR, 2.22; p = 0.014) were independent risk factors related to the occurrence of POUR.

CONCLUSIONS

The significant risk factors of POUR among elderly patients undergoing hip fracture surgery were early indwelling catheter removal and male gender. Therefore, early removal of indwelling catheter in elderly patients following hip fracture surgery may increase the risk of POUR, especially in male patients.

Risk factors for 90-day reoperation and readmission after lumbar surgery for lumbar spinal stenosis

OBJECTIVES

The objective of this study was to evaluate the incidence and risk factors for 90-day readmission and reoperation after elective surgery for lumbar spinal stenosis (LSS).

METHODS

The authors performed a retrospective consecutive cohort analysis of patients undergoing posterior lumbar decompression with or without fusion for LSS with claudication from January 2014 through December 2015.

RESULTS

Data were collected on 1592 consecutive patients. The mean age at surgery was 67.4 ± 10.1 years and 45% of patients were female. The 90-day reoperation rate was 4.7%, and 69.3% of the reoperations occurred within the first 30 days. The 90-day readmission rate was 7.2%. Multivariable analysis showed that postoperative development of a surgical site infection (SSI; odds ratio [OR] 14.09, 95% confidence interval [CI] 7.86–25.18), acute kidney injury (AKI; OR 6.76, 95% CI 2.39–19.57), and urinary tract infection (UTI; OR 3.96, 95% CI 2.43–6.37), as well as a history of congestive heart failure (CHF; OR 3.03, 95% CI 1.69–5.28), were significant risk factors for readmission within 90 days. Male sex (OR 0.60, 95% CI 0.38–0.92) was associated with decreased odds for readmission. With regards to reoperation, development of SSI (OR 25.06, 95% CI 13.54–46.51), sepsis (OR 7.63, 95% CI 1.52–40.59), UTI (OR 2.54, 95% CI 1.31–4.76), and increased length of stay (LOS; OR 1.25, 95% CI 1.17–1.33) were found to be significant risk factors. A subsequent analysis found that morbid obesity (OR 6.99), history of coronary artery disease (OR 2.263), increased duration of surgery (OR 1.004), and LOS (OR 1.07) were significant risk factors for developing an SSI.

CONCLUSIONS

Overall, this study found rates of 4.7% and 7.2% for reoperation and readmission, respectively, within 90 days: 30.7% of the reoperations and 44.7% of the readmissions occurred beyond the first 30 days. A diagnosis of SSI, AKI, UTI, and history of CHF were significant factors for readmission, while male sex was associated with decreased odds for readmission. A diagnosis of SSI, sepsis, UTI, and increased LOS were found to be significant predictors for reoperation. Understanding 90-day complication rates is imperative because there has been increased discussion and healthcare policy extending the global postoperative window to 90 days. Current literature supports a readmission rate of 3%–9% after spine surgery. However, this literature either is limited to a 30-day window or does not stratify between different types of spine surgeries.

ABBREVIATIONS

AKI = acute kidney injury; BPH = benign prostate hyperplasia; CAD = coronary artery disease; CHF = congestive heart failure; CI = confidence interval; CMS = Centers for Medicare and Medicaid Services; COPD = chronic obstructive pulmonary disease; DM = diabetes mellitus; EBL = estimated blood loss; LOS = length of stay; LSS = lumbar spinal stenosis; OR = odds ratio; POUR = postoperative urinary retention; SSI = surgical site infection; UTI = urinary tract infection.

Adverse events and their risk factors 90 days after cervical spine surgery: analysis from the Michigan Spine Surgery Improvement Collaborative

OBJECTIVE

The Michigan Spine Surgery Improvement Collaborative (MSSIC) is a statewide, multicenter quality improvement initiative. Using MSSIC data, the authors sought to identify 90-day adverse events and their associated risk factors (RFs) after cervical spine surgery.

METHODS

A total of 8236 cervical spine surgery cases were analyzed. Multivariable generalized estimating equation regression models were constructed to identify RFs for adverse events; variables tested included age, sex, diabetes mellitus, disc herniation, foraminal stenosis, central stenosis, American Society of Anesthesiologists Physical Classification System (ASA) class > II, myelopathy, private insurance, anterior versus posterior approach, revision procedures, number of surgical levels, length of procedure, blood loss, preoperative ambulation, ambulation day of surgery, length of hospital stay, and discharge disposition.

RESULTS

Ninety days after cervical spine surgery, adverse events identified included radicular findings (11.6%), readmission (7.7%), dysphagia requiring dietary modification (feeding tube or nothing by mouth [NPO]) (6.4%), urinary retention (4.7%), urinary tract infection (2.2%), surgical site hematoma (1.1%), surgical site infection (0.9%), deep vein thrombosis (0.7%), pulmonary embolism (0.5%), neurogenic bowel/bladder (0.4%), myelopathy (0.4%), myocardial infarction (0.4%), wound dehiscence (0.2%), claudication (0.2%), and ileus (0.2%). RFs for dysphagia included anterior approach (p < 0.001), fusion procedures (p = 0.030), multiple-level surgery when considering anterior procedures only (p = 0.037), and surgery duration (p = 0.002). RFs for readmission included ASA class > II (p < 0.001), while preoperative ambulation (p = 0.001) and private insurance (p < 0.001) were protective. RFs for urinary retention included increasing age (p < 0.001) and male sex (p < 0.001), while anterior-approach surgery (p < 0.001), preoperative ambulation (p = 0.001), and ambulation day of surgery (p = 0.001) were protective. Preoperative ambulation (p = 0.010) and anterior approach (p = 0.002) were protective of radicular findings.

CONCLUSIONS

A multivariate analysis from a large, multicenter, prospective database identified the common adverse events after cervical spine surgery, along with their associated RFs. This information can lead to more informed surgeons and patients. The authors found that early mobilization after cervical spine surgery has the potential to significantly decrease adverse events.

Risk factors for surgical site infection following lumbar spinal surgery: a meta-analysis

Objective

To identify risk factors for surgical site infection (SSI) in patients who had undergone lumbar spinal surgery.

Methods

Studies published in PubMed, Web of Science, and Embase were systematically reviewed to determine risk factors for SSI following lumbar spinal surgery. Results are expressed as risk ratios (RRs) with 95% CIs and weighted mean difference (WMD) with 95% CI. A fixed-effect or random-effect model was used to pool the estimates according to heterogeneity among the studies included.

Results

Sixteen studies involving 13,393 patients were included in this meta-analysis. Pooled estimates suggested that diabetes (RR 2.19, 95% CI 1.43–3.36; P<0.001), obesity (RR 2.87, 95% CI 1.62–5.09; P<0.001), BMI (WMD 1.32 kg/m², 95% CI 0.39–2.25; P=0.006), prolonged operating time (WMD 24.96 minutes, 95% CI 14.77–35.15; P<0.001), prolonged hospital stay (WMD 2.07 days, 95% CI 0.28–3.87; P=0.024), hypertension (RR 1.28, 95% CI 1.08–1.52; P=0.005), and previous surgery (RR 2.06, 95% CI 1.39–3.06; P<0.001) were independent risk factors for SSI in patients who had undergone lumbar spine surgery. Current smoking (RR 0.89, 95% CI 0.75–1.06; P=0.178), American Society of Anesthesiologists grade >2 (RR 2.63, 95% CI 0.84–8.27; P=0.098), increased age (WMD 1.43 years, 95% CI −1.15 to 4.02; P=0.278), COPD (RR 1.21, 95% CI 0.68–2.17; P=0.521), cardiovascular disease (RR 1.63, 95% CI 0.40–6.70; P=0.495), rheumatoid arthritis (RR 1.76, 95% CI 0.53–5.90; P=0.359), and osteoporosis (RR 1.91, 95% CI 0.79–4.63; P=0.152) were not risk factors for postoperative SSI.

Conclusion

Our results identified several important factors that increased the risk of postoperative SSI. Knowing these risk factors, surgeons could adequately analyze and evaluate risk factors in patients and then develop prevention measurements to reduce the rate of SSI.