Smoking is Associated with Increased Blood Loss and Transfusion Use After Lumbar Spinal Surgery

Smoking impacts outcomes in transcervical Zenker's diverticulectomy

PURPOSE

There is sparse literature discussing the impact of smoking on postoperative outcomes following surgical treatment of Zenker's diverticulum. In this study, we seek to characterize differences in the management and outcomes of open Zenker's diverticulectomy based on patient smoking status.

METHODS AND MATERIALS

This paper is a retrospective cohort review. The 2005-2018 American College of Surgeons National Surgical Quality Improvement (ACS-NSQIP) database was queried for patients undergoing open Zenker's diverticulectomy. Chi-square and multivariable logistic regression were performed to determine statistical associations between postoperative outcomes and smoking status.

RESULTS

Of the 715 identified patients, 70 (9.8 %) were smokers and 645 (91.2 %) were non-smokers. Smokers were younger than non-smokers (mean 63.9 vs. 71.7 years, p < 0.001) and more likely to have a prolonged operative time (20.0 % vs. 11.6 %, p = 0.044). On multivariable regression analysis controlling for demographics and comorbidities, smokers had greater odds than non-smokers for developing overall postoperative complications (OR: 2.776, p = 0.013), surgical infections (OR: 3.194, p = 0.039), medical complications (OR: 3.563, p = 0.011), and medical infections (OR: 1.247, p = 0.016). Smokers also had greater odds for requiring ventilation/intubation (OR: 8.508, p = 0.025) and having a prolonged postoperative stay (OR: 2.425, p = 0.030).

CONCLUSION

In a cohort of patients undergoing transcervical Zenker's diverticulectomy, smokers are at increased risk for overall complications, medical complications, medical infections, surgical infections, prolonged postoperative stay, and ventilation/intubation.

Risk factors and prognostic significance of early postoperative complications for patients who underwent pneumonectomy for lung cancer

BACKGROUND

Although pneumonectomy has relatively high mortality and morbidity rates, it remains valid in the surgical treatment of lung cancer. This study aims to evaluate the prognostic significance of postoperative complications after pneumonectomy and demonstrate the risk factors related to early postoperative complications.

METHODS

Patients who underwent pneumonectomy for non-small cell lung cancer between January 2008 and May 2021 were included in the study. Factors related to the development of early postoperative complications and overall survival were evaluated by univariate and multivariate analyses.

RESULTS

A total of 136 patients were included in the study. Early postoperative complications were seen in 33 (24.3%) patients and late postoperative complications in 7 (5.1%) patients. The amount of cigarette smoking, and the operation side were the independent variables that affect the development of early postoperative complications. In multivariate analysis, smoking amount and pericardial invasion were associated with the development of postoperative hemorrhage, and advanced age was associated with the development of postoperative pneumonia.

CONCLUSIONS

Early postoperative complications have a negative effect on the prognosis after pneumonectomy therefore careful patient selection and preoperative risk assessment are essential to minimize the occurrence of complications and improve patient outcomes.

TRIAL REGISTRATION

This observational study was approved by the (Ethical Committee of Dr. Suat Seren Chest Diseases and Chest Surgery Education and Research Center) Institutional Review Board of our center (E-49109414-604.02.02-218625439).

The effect of perioperative sequential application of multiple doses of tranexamic acid on postoperative blood loss after PLIF: a prospective randomized controlled trial

BACKGROUND

Tranexamic acid (TXA) has been utilized in spinal surgery to effectively reduce intraoperative blood loss (IBL) and allogeneic blood transfusion rates. However, the traditional TXA regimen might last the entire duration of hyperfibrinolysis caused by surgical trauma, resulting in its limited ability to reduce postoperative blood loss (PBL). Therefore, the aim of this study was to investigate the effectiveness of perioperative sequential administration of multiple doses of TXA in reducing PBL in patients who underwent posterior lumbar interbody fusion (PLIF).

METHODS

From October 2022 to June 2023, 231 patients who were diagnosed with lumbar degenerative disease and scheduled to undergo PLIF were prospectively enrolled in the present study. The patients were randomly divided into three groups. Moreover, all patients received an intravenous injection of TXA at a dose of 15 mg/kg 15 min before the surgical skin incision. Patients in Group A received a placebo of normal saline after surgery, while patients in Group B received three additional intravenous injections of TXA at a dose of 15 mg/kg every 24 h. Patients in Group C received three additional intravenous injections of TXA at a dose of 15 mg/kg every 5 h. The primary outcome measure was PBL. In addition, this study assessed total blood loss (TBL), IBL, routine blood parameters, liver and kidney function, coagulation parameters, fibrinolysis indexes, inflammatory indicators, drainage tube removal time (DRT), length of hospital stay (LOS), blood transfusion rate, and incidence of complications for all subjects.

RESULTS

The PBL, TBL, DRT, and LOS of Group B and Group C were significantly lower than those of Group A ( P <0.05). The level of D-dimer (D-D) in Group C was significantly lower than that in Group A on the first day after the operation ( P =0.002), and that in Group B was significantly lower than that in Group A on the third day after the operation ( P =0.003). The interleukin-6 levels between the three groups from 1 to 5 days after the operation were in the order of Group A > Group B > Group C. No serious complications were observed in any patient. The results of multiple stepwise linear regression analysis revealed that PBL was positively correlated with incision length, IBL, smoking history, history of hypertension, preoperative fibrinogen degradation product level, and blood transfusion. It was negatively correlated with preoperative levels of fibrinogen, red blood cells, blood urea nitrogen, and age. Compared to female patients, male patients had an increased risk of PBL. Finally, the incidence of PBL was predicted.

CONCLUSIONS

Sequential application of multiple doses of TXA during the perioperative period could safely and effectively reduce PBL and TBL, shorten DRT and LOS, reduce postoperative D-D generation, and reduce the postoperative inflammatory response. In addition, this study provided a novel prediction model for PBL in patients undergoing PLIF.

Bone Mineral Density T-Score is an Independent Predictor of Major Blood Loss in Adult Spinal Deformity Surgery

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVE

The purpose of this study was to determine the effect of low bone mineral density (BMD), as assessed by preoperative Dual-energy X-ray Absorptiometry (DEXA) scans, on intraoperative blood loss following adult spinal deformity (ASD) surgery.

METHODS

Patients who received spinal fusion for ASD (>5 levels fused) at a single academic center from 2010-2018 were included in this study. The lowest preoperative T-score was recorded for patients who had preoperative DEXA scans within a year of surgery. Patients with liver/kidney disease or on prescription anticoagulant medication were excluded. Major blood loss was a binary variable defined as above or below the 90th percentile of our cohort. Binomial regression was performed controlling for age, number of vertebrae fused, 3-column osteotomy, primary vs. revision surgery, preoperative platelet count, and if the patient was taking medication for osteoporosis.

RESULTS

91 patients were identified in the cohort. Mean age was 63 ± 11.6 years, 81% female. 56 (62%) of cases included revision of previous instrumentation. Patients had a mean SVA of 9.6 ± 8.6 cm and median of 9 vertebrae fused (range 5-22). The average T-score was -1.2 ± 1.0. Each point lower T-score was associated with significantly higher odds of major blood loss (OR 2.5, 95% CI 1.0 - 5.9) when controlling for age, number of vertebrae fused, 3-column osteotomy, preoperative platelet count and primary vs. revision surgery.

CONCLUSIONS

Preoperative T-score is independently associated with increased odds of major blood loss in ASD surgery.

Development and validation of a web-based artificial intelligence prediction model to assess massive intraoperative blood loss for metastatic spinal disease using machine learning techniques

BACKGROUND CONTEXT

Intraoperative blood loss is a significant concern in patients with metastatic spinal disease. Early identification of patients at high risk of experiencing massive intraoperative blood loss is crucial as it allows for the development of appropriate surgical plans and facilitates timely interventions. However, accurate prediction of intraoperative blood loss remains limited based on prior studies.

PURPOSE

The purpose of this study was to develop and validate a web-based artificial intelligence (AI) model to predict massive intraoperative blood loss during surgery for metastatic spinal disease.

STUDY DESIGN/SETTING

An observational cohort study.

PATIENT SAMPLE

Two hundred seventy-six patients with metastatic spinal tumors undergoing decompressive surgery from two hospitals were included for analysis. Of these, 200 patients were assigned to the derivation cohort for model development and internal validation, while the remaining 76 were allocated to the external validation cohort.

OUTCOME MEASURES

The primary outcome was massive intraoperative blood loss defined as an estimated blood loss of 2,500 cc or more.

METHODS

Data on patients' demographics, tumor conditions, oncological therapies, surgical strategies, and laboratory examinations were collected in the derivation cohort. SMOTETomek resampling (which is a combination of Synthetic Minority Oversampling Technique and Tomek Links Undersampling) was performed to balance the classes of the dataset and obtain an expanded dataset. The patients were randomly divided into two groups in a proportion of 7:3, with the most used for model development and the remaining for internal validation. External validation was performed in another cohort of 76 patients with metastatic spinal tumors undergoing decompressive surgery from a teaching hospital. The logistic regression (LR) model, and five machine learning models, including K-Nearest Neighbor (KNN), Decision Tree (DT), XGBoosting Machine (XGBM), Random Forest (RF), and Support Vector Machine (SVM), were used to develop prediction models. Model prediction performance was evaluated using area under the curve (AUC), recall, specificity, F1 score, Brier score, and log loss. A scoring system incorporating 10 evaluation metrics was developed to comprehensively evaluate the prediction performance.

RESULTS

The incidence of massive intraoperative blood loss was 23.50% (47/200). The model features were comprised of five clinical variables, including tumor type, smoking status, Eastern Cooperative Oncology Group (ECOG) score, surgical process, and preoperative platelet level. The XGBM model performed the best in AUC (0.857 [95% CI: 0.827, 0.877]), accuracy (0.771), recall (0.854), F1 score (0.787), Brier score (0.150), and log loss (0.461), and the RF model ranked second in AUC (0.826 [95% CI: 0.793, 0.861]) and precise (0.705), whereas the AUC of the LR model was only 0.710 (95% CI: 0.665, 0.771), the accuracy was 0.627, the recall was 0.610, and the F1 score was 0.617. According to the scoring system, the XGBM model obtained the highest total score of 55, which signifies the best predictive performance among the evaluated models. External validation showed that the AUC of the XGBM model was also up to 0.809 (95% CI: 0.778, 0.860) and the accuracy was 0.733. The XGBM model, was further deployed online, and can be freely accessed at https://starxueshu-massivebloodloss-main-iudy71.streamlit.app/.

CONCLUSIONS

The XGBM model may be a useful AI tool to assess the risk of intraoperative blood loss in patients with metastatic spinal disease undergoing decompressive surgery.

Risk Factors for Significant Intraoperative Blood Loss during Anterior Cervical Decompression and Fusion for Degenerative Cervical Diseases

OBJECTIVES

Anterior cervical decompression and fusion (ACF) has become a widely accepted surgical treatment for degenerative cervical diseases, but occasionally, significant intraoperative blood loss (SIBL), which is defined as IBL of 500 mL or more, will occur. We aimed to investigate the independent risk factors for SIBL during ACF for degenerative cervical diseases.

METHODS

We enrolled 1150 patients who underwent ACF for degenerative cervical diseases at our hospital between 2013 and 2019. The patients were divided into two groups: the SIBL group (n = 38) and the non-SIBL group (n = 1112). Demographic, surgical and radiographic data were recorded prospectively to investigate the independent risk factors for SIBL. For counting data, the chi-square test or Fisher's exact probability test was used. Student's t-test or the Mann-Whitney rank sum test was used for comparisons between groups of measurement data. Univariate analysis and multivariate logistic regression analysis were further used to analyze the significance of potential risk factors.

RESULTS

The incidence of SIBL during ACF was 3.3% (38/1150). A multivariate analysis revealed that female sex (odds ratio [OR], 6.285; 95% confidence interval [CI], 2.707-14.595; p < 0.001), corpectomy (OR, 3.872; 95% CI, 1.616-9.275; p = 0.002), duration of operation ≥150 min (OR, 8.899; 95% CI, 4.042-19.590; p < 0.001), C3 involvement (OR, 4.116; 95% CI, 1.808-9.369; p = 0.001) and ossification of posterior longitudinal ligament (OPLL) at the surgical level (OR, 6.007; 95% CI, 2.218-16.270; p < 0.001) were independent risk factors for SIBL. Patients with SIBL had more days of first-degree/intensive nursing (p = 0.003), longer length of stay (p = 0.003) and higher hospitalization costs (p = 0.023).

CONCLUSION

Female sex, corpectomy, duration of operation, C3 involvement and OPLL at the surgical level were independent risk factors for SIBL during ACF. SIBL in ACF was associated with more days of first-degree/intensive nursing, longer length of stay and higher hospitalization costs.

Perioperative Transfusions in Veterans Following Noncardiac Procedures

Background: Perioperative blood transfusions are associated with increased morbidity and mortality. Each surgical specialty is associated with unique operative variables. Moreover, transfusion rates vary across specialty. This article seeks to elucidate variables both common and unique to surgical specialties. Materials and Methods: This study was a retrospective review of 5344 patients from the prospectively maintained Veterans Affairs Surgical Quality Improvement Project at a single-level 1A tertiary Veterans Affairs Medical Center. Data collected included demographic information, preoperative clinical variables, postoperative outcomes, and perioperative transfusion (within 72 hours of procedure). Patients were stratified based on whether they received a transfusion. Univariate and multivariate analyses were performed. P values <.05 were significant. Results: Of the 5344 patients included in the study, 153 required perioperative transfusion of at least one unit of packed red blood cells. Patients who underwent transfusion were more likely to be men, have an underlying bleeding disorder, and have more preoperative risk factors. Although unique risk factors were found within most specialties, there was no statistically significant difference in postoperative complications between surgical specialties. Patients requiring transfusion had higher rates of morbidity and mortality. Elevated preoperative hematocrit was significantly protective against requiring transfusion across most specialties. Conclusions: Specialty-based differences in transfusion requirement may be due to the proportion of older and more frail patients, hospital transfusion thresholds, and surgical complexity. Hematocrit, however, could be an effective target for mitigating cost and morbidity associated with transfusion. Preoperative hematocrit optimization through B12, folate, iron dosing, and erythropoietin supplementation could be a useful strategy.

Principles of minimize bleeding and the transfusion of blood and its components in operated patients - surgical aspects

One of the target of perioperative tratment in surgery is decreasing intraoperative bleeding, which increases the number of perioperative procedures, mortality and treatment costs, and also causes the risk of transfusion of blood and its components. Trying to minimize the blood loss(mainly during the operation) as well as the need to transfuse blood and its components (broadly understood perioperative period) should be standard treatment for a patient undergoing a procedure. In the case of this method, the following steps should be taken: 1) in the preoperative period: identyfication of risk groups as quickly as possible, detecting and treating anemia, applying prehabilitation, modyfying anticoagulant treatment, considering donating one's own blood in some patients and in selected cases erythropoietin preparations; 2) in the perioperative period: aim for normothermia, normovolemia and normoglycemia, use of surgical methods that reduce bleeding, such as minimally invasive surgery, high-energy coagulation, local hemostatics, prevention of surgical site infection, proper transfusion of blood and its components if it occurs; 3) in the postoperative period: monitor the condition of patients, primarily for the detection of bleeding, rapid reoperation if required, suplementation (oral administration preferred) nutrition with microelements (iron) and vitamins, updating its general condition. All these activities, comprehensively and in surgical cooperation with the anesthesiologist, should reduce the blood loss and transfusion of blood and its components.

Perioperative Management of Comorbidities in Spine Surgery

The number of spinal operations performed in the United States has significantly increased in recent years. Along with these rising numbers, there has been a corresponding increase in the number of patient comorbidities. The focus of this article is to review comorbidities in Spine surgery patients and outline strategies to optimize patients and avoid complications.

Effects of smoking on controlled hypotension with nitroglycerin during ear-nose-throat surgery

Background and Aim

In this study, the aim was to research the effects of smoking habits on controlled hypotension administered with nitroglycerin during ear-nose-throat surgery.

Materials and Methods

This study administered controlled hypotension with nitroglycerin and total intravenous anesthesia to a total of 80 patients undergoing septoplasty operations. The patients were divided into two groups of 40 non-smokers (Group 1) and 40 smokers (Group 2). Intravenous propofol infusion was used for anesthesia maintenance. Nitroglycerin with 0.25-1 μg/kg/min dose was titrated to provide controlled hypotension. During this process, the hemodynamic parameters of patients, total propofol and nitroglycerin amounts used, operation duration, and duration of controlled hypotension were recorded at the end of the operation. At the end of the operation, the surgeon assessed the lack of blood in the surgical field with Fromme Scale.

Results

Fromme scale values were significantly higher in Group 2 compared to Group 1. The MAP values at 10, 20, 30 min, and end of operation were lower, while 10- and 20-min heart rate values were higher in Group 2 compared to Group 1.

Conclusion

Nitroglycerin, chosen for controlled hypotension to reduce hemorrhage in the surgical field during nasal surgery, was shown to cause more pronounced hypotension and reflex tachycardia due to endothelial dysfunction linked to nicotine in patients who smoke. Despite lower pressure values in the smoking group, the negative effects of nicotine on platelet functions combined with similar effects of nitroglycerin to increase bleeding amounts.

Patient-reported outcomes after posterior surgical stabilization for thoracolumbar junction fractures: A pilot study with combined patient-reported outcome measure methodology

Background

Thoracolumbar junction fractures (TLJFs) attract controversy for several parameters, including surgery versus conservative treatment, fusion versus stabilization, open versus percutaneous surgery, construct length, and downstream metalwork extraction.

Aims and Objectives

The aim of this pilot study was to assess the effectiveness of surgical treatment in patients with burst (AO Classification Type A4) TLJFs using patient-reported outcome measures (PROMs) and evaluate and compare different PROMs in this clinical scenario.

Materials and Methods

Patient records of consecutive patients who underwent posterior stabilization surgery for TLJFs were retrospectively reviewed. Data were collected on demographics, medical and social history, neurological examination, and postoperative complications. Telephone interviews and a combined PROM methodology (Numerical Rating Scale [NRS], EuroQol [EQ]-5D-5L, and Oswestry Disability Index [ODI]) were utilized to assess the effectiveness of intervention. Descriptive statistics were used to analyze exposure variables and outcome measures. Spearman's rank correlation was used for the outcome measures.

Results

Thirteen patients were included. The mean age was 42 ± 16 years; the male: female ratio was 8:5; the mean follow-up was 18.9 ± 6.4 months. The mean NRS score was 3.3 ± 2.5, in line with a median score of 2 (2) on EQ-5D-5L pain/discomfort scale. Statistically significant correlations were found between several PROMs: pain-EQ-5D-5L and NRS (rs = 0.8, P = 0.002), pain-EQ-5D-5L and ODI (rs = 0.8, P = 0.001), usual anxiety/depression-EQ-5D-5L, and ODI (rs = 0.7, P = 0.008).

Conclusion

A combined PROM methodology showed supportive evidence for safety and efficacy in the surgical stabilization of burst TLJFs. This alleviated significant pain and prevented neurological deficit and major disability. The preliminary widespread correlation between these PROMs supports further larger studies of their combined use in clinical practice, to measure the outcomes of spine trauma patients.

Unplanned Readmission Following Early Postoperative Complications After Fusion Surgery in Adult Spine Deformity: A Multicentric Study

STUDY DESIGN

Multicentric retrospective study, Level of evidence III.

OBJECTIVE

The objective of this multicentric study was to analyze the prevalence and risk factors of early postoperative complications in adult spinal deformity patients treated with fusion. Additionally, we studied the impact of complications on unplanned readmission and hospital length of stay.

METHODS

Eight spine centers from 6 countries in Latin America were involved in this study. Patients with adult spinal deformity treated with fusion surgery from 2017 to 2019 were included. Baseline and surgical characteristics such as age, sex, comorbidities, smoking, number of levels fused, number of surgical approaches were analyzed. Postoperative complications at 30 days were recorded according to Clavien-Dindo and Glassman classifications.

RESULTS

172 patients (120 females/52 males, mean age 59.4 ± 17.6) were included in our study. 78 patients suffered complications (45%) at 30 days, 43% of these complications were considered major. Unplanned readmission was observed in 35 patients (20,3%). Risk factors for complications were: Smoking, previous comorbidities, number of levels fused, two or more surgical approaches and excessive bleeding. Hospital length of stay in patients without and with complications was of 7.8 ± 13.7 and 17 ± 31.1 days, respectively (P 0.0001).

CONCLUSION

The prevalence of early postoperative complications in adult spinal deformity patients treated with fusion was of 45% in our study with 20% of unplanned readmissions at 30 days. Presence of complications significantly increased hospital length of stay.

Anesthesiologists and the Other Pandemic: Tobacco Use

Tobacco use will kill a projected 1 billion people in the 21st century in one of the deadliest pandemics in history. Tobacco use disorder is a disease with a natural history, pathophysiology, and effective treatment options. Anesthesiologists can play a unique role in fighting this pandemic, providing both immediate (reduction in perioperative risk) and long-term (reduction in tobacco-related diseases) benefits to their patients who are its victims. Receiving surgery is one of the most powerful stimuli to quit tobacco. Tobacco treatments that combine counseling and pharmacotherapy (e.g., nicotine replacement therapy) can further increase quit rates and reduce risk of morbidity such as pulmonary and wound-related complications. The perioperative setting provides a great opportunity to implement multimodal perianesthesia tobacco treatment, which combines multiple evidence-based tactics to implement the four core components of consistent ascertainment and documentation of tobacco use, advice to quit, access to pharmacotherapy, and referral to counseling resources.

Smoking Is Associated With Lower Satisfaction in Nondiabetic Patients Undergoing Minimally Invasive Single-level Transforaminal Lumbar Interbody Fusion

STUDY DESIGN

This was a retrospective review of prospectively collected registry data.

OBJECTIVE

The objective of this study was to investigate the effect of smoking on 2 years postoperative functional outcomes, satisfaction, and radiologic fusion in nondiabetic patients undergoing minimally invasive transforaminal lumbar interbody fusion (TLIF) for degenerative spine conditions.

SUMMARY OF BACKGROUND DATA

There is conflicting data on the effect of smoking on long-term functional outcomes following lumbar fusion. Moreover, there remains a paucity of literature on the influence of smoking within the field of minimally invasive spine surgery.

METHODS

Prospectively collected registry data of nondiabetic patients who underwent primary single-level minimally invasive TLIF in a single institution was reviewed. Patients were stratified based on smoking history. All patients were assessed preoperatively and postoperatively using the Numerical Pain Rating Scale for back pain and leg pain, Oswestry Disability Index, Short-Form 36 Physical and Mental Component Scores. Satisfaction was assessed using the North American Spine Society questionnaire. Radiographic fusion rates were compared.

RESULTS

In total, 187 patients were included, of which 162 were nonsmokers, and 25 had a positive smoking history. In our multivariate analysis, smoking history was insignificant in predicting for minimal clinically important difference attainment rates in Physical Component Score and fusion grading outcomes. However, in terms of satisfaction score, positive smoking history remained a significant predictor (odds ratio=4.7, 95% confidence interval: 1.10-20.09, P=0.036).

CONCLUSIONS

Nondiabetic patients with a positive smoking history had lower satisfaction scores but comparable functional outcomes and radiologic fusion 2 years after single-level TLIF. Thorough preoperative counseling and smoking cessation advice may help to improve patient satisfaction following minimally invasive spine surgery.

LEVEL OF EVIDENCE

Level III-nonrandomized cohort study.

The effect of smoking on achieving meaningful clinical outcomes one year after lumbar tubular microdecompression: a matched-pair cohort analysis

BACKGROUND CONTEXT

There has been a shift in the spine literature in reporting meaningful outcomes, including meaningful clinically important difference (MCID), after surgery. The evidence on the effect of tobacco smoking at the time of lumbar tubular microdecompression (LTMD) on meaningful outcomes is limited.

PURPOSE

To compare differences in 1-year functional outcomes and rates of achieving MCID between current smokers and non-smokers who underwent LTMD for lumbar spinal stenosis (LSS).

STUDY DESIGN

A nested case control study to compare the difference in patient reported outcomes (PROs) between smokers and non-smokers 1-year after undergoing LTMD.

PATIENT SAMPLE

This study included patients that underwent single level LTMD by a single surgeon between January 2014 through August 2019.

OUTCOME MEASURES

Preoperative and postoperative PROs were recorded using the questionnaires EQ-5D, Oswestry Disability Index (ODI), and the visual analog scale (VAS) for back pain and leg pain. The MCID was also used.

METHODS

Current tobacco smokers at the time of surgery were matched 1:2 to non-smokers by age (+/- 1year). Preoperative and postoperative functional scores were compared between the two groups using independent t-tests. Additionally, thresholds for achieving MCID were calculated for each individual functional score, and were compared using Fisher's exact test.

RESULTS

Of the 183 patients with 1-year follow-up who met inclusion criteria, 35 patients were identified as smokers and were matched to 70 non-smokers. No statistical differences were identified between age, BMI, or gender. Comparison of preoperative PROs showed no statistically significant differences between smokers and non-smokers (p>0.05 for all), while smokers had statistically lower EQ-5D (p<0.001) and higher ODI (p=0.05), VAS back (p=0.033), and VAS leg (p=0.03) score averages at a minimum of one year follow-up. Evaluation of meaningful outcomes demonstrated non-smokers had higher rates of achieving MCID on at least 1 threshold score as compared to smokers (98.5% vs. 91.1%; p=0.043).

CONCLUSIONS

Current smokers at the time of surgery have inferior postoperative EQ-5D scores, increased pain and disability, and lower odds of achieving the MCID at 1-year after undergoing LTMD when compared to patients without any smoking history.

Risk Factors for Increased Surgical Drain Output After Transforaminal Lumbar Interbody Fusion

OBJECTIVE

To investigate the risk factors for increased surgical drain output after transforaminal lumbar interbody fusion (TLIF).

METHODS

Patients who underwent TLIF in a single center from June 2017 to January 2020 were included in this study. They were divided into the increased surgical drain output group and no increased surgical drain output group according to the boundary of the median drain output. Patients' demographic and clinical parameters were compared between the 2 groups. Risk factors for increased surgical drain output were identified by univariate and multivariate logistic regression analysis.

RESULTS

This study enrolled 368 patients who underwent TLIF. Among them, 187 patients had increased surgical drain output (drain output ≥50th percentile or 480 mL). Univariate analysis showed that age (P < 0.001), smoking status (P = 0.002), number of fused levels (P < 0.001), intraoperative blood loss (P < 0.001), intraoperative end plate injury (P < 0.001), administration of tranexamic acid (TXA) (P = 0.002), and surgical duration (P < 0.001) were significantly associated with increased surgical drain output. Multiple logistic regression analysis revealed that older age (P = 0.001), smoking (P = 0.005), more fused levels (P < 0.001), and intraoperative end plate injury (P = 0.017) were the independent risk factors, while administration of TXA (P = 0.012) was a protective factor.

CONCLUSIONS

This study showed that older age, smoking, more fused levels, and intraoperative end plate injury were the independent risk factors, while administration of TXA was a protective factor for increased surgical drain output after TLIF.

How Does Smoking Influence Patient-reported Outcomes in Patients After Lumbar Fusion?

STUDY DESIGN

A retrospective cohort study.

OBJECTIVE

The goal of this study was to determine the effect of smoking on patient-reported outcome measurements (PROMs) after lumbar fusion surgery.

SUMMARY OF BACKGROUND DATA

Although smoking is known to decrease fusion rates after lumbar fusion, there is less evidence regarding the influence of smoking on PROMs after surgery.

METHODS

Patients undergoing between 1 and 3 levels of lumbar fusion were divided into 3 groups on the basis of preoperative smoking status: never smokers (NS); current smokers (CS); and former smokers (FS). PROMs collected for analysis include the Physical Component Score (PCS-12), Mental Component Score (MCS-12), Oswestry Disability Index (ODI), and Visual Analogue Scale back (VAS back) and leg (VAS leg) pain scores. Preoperative and postoperative PROMs were compared between groups. A multiple linear regression analysis was performed to determine whether preoperative smoking status was a predictor of change in PROM scores.

RESULTS

A total of 220 (60.1%) NS, 52 (14.2%) CS, and 94 (25.7%) FS patients were included. Patients in most groups improved within each of the PROMs analyzed (P<0.05). VAS leg pain (P=0.001) was found to significantly differ between groups, with NS and FS having less disability than CS (3.6 vs. 2.0, P=0.010; and 3.6 vs. 2.4, P=0.022; respectively). Being a CS significantly predicted less improvement in ODI (P=0.035), VAS back (P=0.034), and VAS leg (P<0.001) compared with NS. In addition, NS had a significantly lower 30-day readmission rate than CS or FS (3.2% vs. 5.8% and 10.6%, respectively, P=0.029).

CONCLUSION

CS exhibited worse postoperative VAS leg pain and a lower recovery ratio than never smokers. In addition, being in the CS group was a significant predictor of decreased improvement in ODI, VAS back, and VAS leg scores.

LEVEL OF EVIDENCE

Level III.

The influence of smoking in minimally invasive spinal fusion surgery

Background

The impact of smoking on spinal surgery has been studied extensively, but few investigations have focused on minimally invasive surgery (MIS) of the spine and the difference between complication rates in smokers and non-smokers. We evaluated whether a history of at least one pack-year preoperatively could be used to predict adverse peri- and postoperative outcomes in patients undergoing minimally invasive fusion procedures of the lumbar spine. In a prospective study, we assessed the clinical effectiveness of MIS in an unselected population of 187 patients.

Methods

We evaluated perioperative and postoperative complication rates in MIS fusion techniques of the lumbar spine in smoking and non-smoking patients. MIS fusion was performed using interbody fusion procedures and/or posterolateral fusion alone.

Results

Smokers were significantly younger than non-smokers. We did not encounter infection at the site of surgery or severe wound healing disorder in smokers. We registered no difference between the smoking and non-smoking groups with regard to peri- or postoperative complication rate, blood loss, or length of stay in hospital. We found a significant influence of smoking (p = 0.049) on the overall perioperative complication rate.

Conclusion

MIS fusion techniques seem to be a suitable tool for treating degenerative spinal disorders in smokers.

A novel predictive model of intraoperative blood loss in patients undergoing elective lumbar surgery for degenerative pathologies

BACKGROUND CONTEXT

Intraoperative blood loss (IOBL) is unavoidable during surgery; however, high IOBL is associated with increased morbidity and increased risk for requiring allogenic blood transfusion, itself associated with poorer outcomes.

PURPOSE

Here we sought to develop and validate a predictive calculator for IOBL that could be used by surgeons to estimate likely blood loss.

STUDY DESIGN/SETTING

Retrospective cohort.

PATIENT SAMPLE

Series of consecutive patients who underwent elective lumbar spine surgery for degenerative pathologies over a 27-month period at a single tertiary care center.

OUTCOME MEASURES

Primary outcome was IOBL. Secondary outcome was the occurrence of "major intraoperative bleeding," defined as IOBL exceeding 1 L.

METHODS

Charts of included patients were reviewed for medical comorbidities, preoperative laboratory data, surgical plan, and anesthesia records. Univariate linear regressions were performed to find significant predictors of IOBL, which were then subjected to a multivariate analysis to identify the final model. Model training was performed using 70% of the included cohort and external validation was performed using 30% of the cohort. Results of the model were deployed as a freely available online calculator.

RESULTS

We identified 1,281 patients who met inclusion/exclusion criteria. Mean age was 60±15 years, mean Charlson Comorbidity score was 1.1±1.6, and 51.8% were male. There were no significant differences between the training and validation cohorts with regard to any of the demographic variables or intraoperative variables; tranexamic acid use and surgical invasiveness were also similar in both cohorts. Multivariate analysis identified body mass index (βₙ=7.14; 95% confidence interval [3.15, 11.13]; p<.001), surgical invasiveness (βₙ=29.18; [24.62, 33.74]; p<.001), tranexamic acid use (βₙ=-0.093; [-0.171, -0.014]; p=.02), and surgical duration (βₙ=2.13; [1.75, 2.51]; p<.001) as significant predictors of IOBL. The model had an overall fit of r=0.693 in the validation cohort. Construction of a receiver-operating curve for predicting major IOBL showed a C-statistic of 0.895 within the validation cohort.

CONCLUSION

Here we identify and validate a model for predicting IOBL in patients undergoing lumbar spine surgery. The model was a moderately strong predictor of absolute IOBL and was demonstrated to predict the occurrence of major IOBL with a high degree of accuracy. We propose it may have future utility when counseling patients about surgical morbidity and the probability of requiring transfusion.

Smoking and risk of surgical bleeding: nationwide analysis of 5,452,411 surgical cases

BACKGROUND

Although smoking is associated with several postoperative complications, a possible association with surgical bleeding remains unclear. We examined if smoking is associated with a higher risk of surgical bleeding.

STUDY DESIGN AND METHODS

We included patients from the American College of Surgeons National Surgical Quality Improvement Program 2007-2016 from 680 hospitals across the United States. Patients with information on age, sex, surgical specialty, and smoking status were included. Surgical bleeding was defined as 1 or more red blood cell (RBC) units transfused intraoperatively to 72 hours postoperatively. The association between smoking and surgical bleeding was examined using logistic regressions adjusted for age, sex, body mass index, ethnicity, comorbidities, laboratory values, American Society of Anesthesiologists score, type of anesthesia, duration of surgery, work relative value unit (surrogate for operative complexity), surgical specialty, and procedure year.

RESULTS

A total of 5,452,411 cases were recorded, of whom 19% smoked and 6% received transfusion. Odds ratios for transfusion were 1.06 (95% confidence interval [CI], 1.05-1.07) for smokers versus nonsmokers and 1.06 (95% CI, 1.04-1.09) for current smokers versus never-smokers. Odds ratios for cumulative smoking were 0.97 (95% CI, 0.95-1.00) for greater than 0 to 20 versus 0 pack-years, 1.04 (95% CI, 1.01-1.07) for greater than 20 to 40, and 1.12 (95% CI, 1.09-1.15) for greater than 40 (p for trend < 0.001). Hazard ratios for reoperations due to any cause and to bleeding were 1.28 (95% CI, 1.27-1.31) and 0.99 (95% CI, 0.93-1.04).

CONCLUSION

Smoking was associated with a higher risk of RBC transfusion as a proxy for surgical bleeding across all surgical specialties combined.

Impacts of Preoperative Smoking and Smoking Cessation Time on Preoperative Peripheral Blood Inflammatory Indexes and Postoperative Hospitalization Outcome in Male Patients with Lung Cancer and Surgery Treatment

Objective s To investigate the effects of preoperative smoking and smoking cessation time on preoperative peripheral blood inflammatory indexes and postoperative hospitalization outcomes in male patients with lung cancer and surgery therapy.Methods We retrospectively enrolled 637 male patients who underwent curative-intent lung cancer resection between January 2014 and December 2016. Patients were classified as the current smokers, the never smokers, and the ex-smokers based on their smoking history, and the ex-smokers were allocated into five subgroups according to their smoking cessation times (CeT): CeT≤6 weeks, 6weeks<CeT≤1year, 1year<CeT≤5years, 5years<CeT≤10years, CeT>10years. The preoperative peripheral blood white blood cells (WBCs), albumin, neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), intraoperative blood loss, 30-day mortality, in-hospital days, hospitalization costs, intensive care unit (ICU), admission days and placement time of closed thoracic drainage tube were compared among different groups.Results There were significant differences in WBC (F=5.275, P<0.001) and albumin (F=2.470, P<0.05) among patients of current smokers, ex-smokers with different smoking cessation time, and never-smokers. The blood WBC count in current smokers (7.7×10 ⁹/L) was significantly higher than that in ex-smokers (7.0×10 ⁹/L)and never-smokers (5.9×10 ⁹/L) (t=-2.145, P<0.05; t=-6.073, P<0.01, respectively). The level of peripheral blood albumin in current smokers (41.1 g/L) was lower than that in ex-smokers (42.1 g/L) and never-smokers (43.2 g/L) (t=2.323, P<0.05; t=3.995, P<0.01, respectively). The level of peripheral blood NLR in current smokers (3.7) was higher than that in ex-smokers (3.1) and never smokers (2.8) (t=-1.836, P<0.05; t=-2.889, P<0.01, respectively). There was no significant difference in WBC, albumin and NLR among five subgroups of different smoking cessation time. No significant difference was observed in intraoperative blood loss, 30-day mortality, hospitalization costs, hospital stay, ICU stay and placement time of closed thoracic drainage tube among groups either. Conclusion Smoking increases the preoperative inflammatory indexes in peripheral blood of lung cancer patients. Smoking cessation has beneficial effect on reducing levels of these inflammatory indexes, which may be not impacted by the time length of smoking cessation. Therefore, lung cancer patients should be encouraged to quit smoking at any time.

The Effect of Tobacco Smoking on Adverse Events Following Adult Complex Deformity Surgery: Analysis of 270 Patients From the Prospective, Multicenter Scoli-RISK-1 Study

STUDY DESIGN

Post-hoc analysis of a prospective, multicenter cohort study.

OBJECTIVE

To analyze the impact of smoking on rates of postoperative adverse events (AEs) in patients undergoing high-risk adult spine deformity surgery.

SUMMARY OF BACKGROUND DATA

Smoking is a known predictor of medical complications after adult deformity surgery, but the effect on complications, implant failure and other AEs has not been adequately described in prospective studies.

METHODS

Twenty-six patients with a history of current smoking were identified out of the 272 patients enrolled in the SCOLI-RISK-1 study who underwent complex adult spinal deformity surgery at 15 centers, with 2-year follow-up. The outcomes and incidence of AEs in these patients were compared to the nonsmoking cohort (n = 244) using univariate analysis, with additional multivariate regression to adjust for the effect of patient demographics, complexity of surgery, and other confounders.

RESULTS

The number of levels and complexity of surgery in both cohorts were comparable. In the univariate analysis, the rates of implant failure were almost double (odds ratio 2.28 [0.75-6.18]) in smoking group (n = 7; 26.9%)) that observed in the nonsmoking group (n = 34; 13.9%), but this was not statistically significant (P = 0.088). Surgery-related excessive bleeding (>4 L) was significantly higher in the smoking group (n = 5 vs. n = 9; 19.2% vs. 3.7%; OR 6.22[1.48 - 22.75]; P = 0.006). Wound infection rates and respiratory complications were similar in both groups. In the multivariate analysis, the smoking group demonstrated a higher incidence of any surgery-related AEs over 2 years (n = 13 vs. n = 95; 50.0% vs. 38.9%; OR 2.12 [0.88-5.09]) (P = 0.094).

CONCLUSION

In this secondary analysis of patients from the SCOLI-RISK-1 study, a history of smoking significantly increased the risk of excessive intraoperative bleeding and nonsignificantly increased the rate of implant failure or surgery-related AEs over 2 years. The authors therefore advocate a smoking cessation program in patients undergoing complex adult spine deformity surgery.

LEVEL OF EVIDENCE

2.

The Role of Potentially Modifiable Factors in a Standard Work Protocol to Decrease Complications in Adult Spinal Deformity Surgery: A Systematic Review, Part 1

STUDY DESIGN

Structured Literature Review.

OBJECTIVES

We sought to evaluate the peer-reviewed literature for potentially modifiable patient and surgical factors that could be incorporated into a Standard Work protocol to decrease complications in adult spinal deformity (ASD) surgery.

SUMMARY OF BACKGROUND DATA

Lean Methodology uses Standard Work to improve efficiency and decrease waste and error. ASD is known to have a high surgical complication rate. Several patient and surgical potentially modifiable factors have been suggested to affect complications, including preoperative hemoglobin, bone density, body mass index (BMI), age-appropriate realignment, preoperative albumin/prealbumin, and smoking status. We sought to evaluate the literature for evidence supporting these factors to include in a Standard Work protocol to decrease complications.

METHODS

Each of these six factors was developed into an appropriate clinical question that included the patient population, surgical intervention, a comparison group, and outcomes measure (PICO question). A comprehensive literature search was then performed. The authors reviewed abstracts and analyzed data from included studies. From 456 initial citations with abstract, 173 articles underwent full-text review. The best available evidence for clinical questions regarding the influence of these factors was provided by 93 included studies.

RESULTS

We found fair evidence supporting a low preoperative hemoglobin level associated with increased transfusion rates and decreased BMD and increased BMI associated with increased complication rates. Fair evidence supported low albumin/prealbumin associated with increased complications. There was fair evidence associating smoking exposure to increased reoperations, but conflicting evidence associating it with increased complications. There was no evidence in the literature evaluating age-appropriate realignment and complications.

CONCLUSION

Preoperative hemoglobin, bone density, body mass index, preoperative albumin/prealbumin, and smoking status all are potentially modifiable risk factors that are associated with increased complications in the adult spine surgery population. Developing a Standard Work Protocol for patient evaluation and optimization should include these factors.

LEVEL OF EVIDENCE

Level II.

Effect of preoperative smoking cessation on postoperative pain outcomes in elderly patients with high nicotine dependence

OBJECTIVE

To investigate the effect of smoking cessation before surgery on postoperative pain and analgesic consumption after thoracoscopic radical resection of lung cancer in elderly patients with high nicotine dependence.

METHODS

A total of 107 male patients, ages 60 to 70 years, undergoing elective thoracoscopic radical lung cancer surgery from July 2017 to July 2018 were enrolled into 3 groups: group A (highly nicotine-dependent and discontinued smoking <3 weeks before surgery, n = 36), group B (highly nicotine-dependent and discontinued smoking >3 weeks before surgery, n = 38), and group C (nonsmokers, n = 33). Postoperative sufentanil consumption, visual analog scale (VAS) pain scores at rest and during cough, rescue analgesia, opioid-related adverse events, and patient satisfaction were assessed from 0 to 48 h postoperatively.

RESULTS

Patient characteristics were comparable among the 3 groups. Sufentanil consumption and VAS pain scores from postoperative 0 to 48 h were significantly higher in groups A and B than in group C. In addition, group B had lower sufentanil consumption and pain scores than group A. No differences in the need for rescue analgesia, patient satisfaction, or occurrence of postoperative adverse events, including nausea, vomiting, respiratory depression, and oversedation, were observed among the 3 groups.

CONCLUSION

Compared with nonsmokers, highly nicotine-dependent male patients who were deprived of cigarettes experienced more severe pain and required treatment with more sufentanil after thoracoscopic radical lung cancer surgery. Moreover, preoperative smoking cessation at least 3 weeks before surgery led to better postoperative pain outcomes than smoking cessation within 3 weeks of surgery.

Surgical and Clinical Results of Minimally Invasive Spinal Fusion Surgery in an Unselected Patient Cohort of a Spinal Care Unit

OBJECTIVES

To review the surgical results and to identify possible parameters influencing the clinical outcomes in an unselected patient collective undergoing minimally invasive lumbar interbody fusion in a spinal care unit.

METHODS

A total of 229 adult patients who underwent minimally invasive lumbar spinal fusion between 2008 and 2016 were included in this retrospective analysis. Lumbar fusion was performed using transforaminal interbody fusion (TLIF) devices and posterolateral fusion. To eliminate confounding parameters, in all patients interbody fusion was indicated by lumbar degenerative pathologies, and surgery was performed using the same fusion device. Treatment efficacy was evaluated using scores describing pain (visual analogue scale [VAS]) and health impairment (EQ-5D, Oswestry Disability Index [ODI]). The influence of patient age, obesity, active smoking status, and co-morbidities on clinical outcome and perioperative complications was analyzed.

RESULTS

The patient population reviewed had improved VAS (P_{(leg pain)} ≤ 0.0001, P_{(back pain)} ≤ 0.0001), ODI (P ≤ 0.0001), EQ-VAS (P ≤ 0.0001), and EQ-5D subscales "mobility", "self-care", "pain", and "anxiety" (P_(mobility) ≤ 0.0001, P_(self-care)  = 0.41, P_(pain) ≤ 0.0001, P_(anxiety)  = 0.011) postoperatively. Neither advanced patient age, nor increased body mass index (BMI), hypertension, or active smoking status had a significantly limiting influence on the success of minimally invasive spinal surgeries (MIS). Duration of surgery strongly correlated with the number of spinal levels treated and with intraoperative blood loss (r = 0.774, P ≤ 0.0001, n = 208). Weak positive correlations were found between patient age and duration of surgery (r = 0.184, P = 0.005, n = 229), intraoperative blood loss (r = 0.165, P = 0.012, n = 229), and duration of hospitalization (r = 0.270, P ≤ 0.0001, n = 228), respectively. When compared to non-smokers, smokers were younger (P ≤ 0.0001), and had a significantly lower BMI (P = 0.001), shorter durations of surgery (P ≤ 0.0001), decreased intraoperative blood loss (P = 0.022), and shorter hospital stays (P = 0.006), respectively. Complications occurred in 17 patients (7%) and were not affected by patient age, BMI, hypertension, or active smoking status.

CONCLUSION

Minimally invasive spinal surgery is a safe and effective treatment option and may be superior to open surgery in subpopulations with significant co-morbidities and risk factors, such as elderly and obese patients as well as patients with an active smoking status.

Does the severity of pain correlate with severity of functional disability? Factors influencing 'patient reported outcome measures' in spinal patients

Aims: To assess correlation between the Visual Analogue Scale (VAS) pain score and the Oswestry Disability Index (ODI) and which patient factors can influence patient-reported outcome measures (PROMs). This study also aims to assess the response to the sexual function question of the ODI.

Methods: Retrospective analysis of 200 consecutive patients undergoing a range of different lumbar spinal procedures between July 2012 and September 2015 was performed. Subgroup analysis was also performed on the 122 patients who underwent microdiscectomy and/or decompression procedures only. Data from notes and clinical letters from the patient's first clinic appointment were collected. In addition to these outcome measures, data were also extracted regarding patients' gender, age, smoking status, alcohol use, employment and mental health status.

Results: Significant correlation was found between VAS pain score and ODI (p = 0.002) and between VAS pain score and question 1 of ODI (p = 0.0001). A lower ODI score was reported at time of surgery by those in employment compared to those who are unemployed (p = 0.008). In addition to this, a lower ODI score was reported in those who are self-employed compared to those in employment (p = 0.048) in both cohorts. A significantly higher mean ODI score was shown within the subgroup analysis for current smokers (p = 0.02). None of the other patient factors that were analysed were found to affect PROMs. 65% of patients answered the sexual function question of the ODI.

Conclusions: Significant correlation was demonstrated between VAS pain score and ODI. Those who are in employment are far more likely to report a lower ODI score than those who are unemployed at the time of surgery. Self-employed patients were found to have reported a significantly lower ODI score than those who are in employment. Smoking cessation should be encouraged as those who are current smokers may be more likely to report a higher ODI. As 65% of patients decided to answer the sexual function question of the ODI, this supports its further use.

Allograft Versus Demineralized Bone Matrix in Instrumented and Noninstrumented Lumbar Fusion: A Systematic Review

STUDY DESIGN

Systematic review.

OBJECTIVES

The aim was to determine the fusion efficacy of allograft and demineralized bone matrix (DBM) in lumbar instrumented and noninstrumented fusion procedures for degenerative lumbar disorders.

METHODS

A literature search was conducted using the PubMed and Cochrane databases. To be considered, publications had to meet 4 criteria: patients were treated for a degenerative lumbar disorder, a minimum group size of 10 patients, use of allograft or DBM, and at least a 2-year follow-up. Data on the study population, follow-up time, surgery type, grafting material, fusion rates, and its definition were collected.

RESULTS

The search yielded 692 citations with 17 studies meeting the criteria including 4 retrospective and 13 prospective studies. Six studies used DBM and 11 employed allograft alone or in the combination with autograft. For the allograft, fusion rates ranged from 58% to 68% for noninstrumented and from 68% to 98% for instrumented procedures. For DBM, fusion rates were 83% for noninstrumented and between 60% and 100% for instrumented lumbar fusion procedures.

CONCLUSIONS

Both allograft and DBM appeared to provide similar fusion rates in instrumented fusions. On the other hand, in noninstrumented procedures DBM was superior. However, a large variation in the type of surgery, outcomes collection, lack of control groups, and follow-up time prevented any significant conclusions. Thus, studies comparing the performance of allograft and DBM to adequate controls in large, well-defined patient populations and with a sufficient follow-up time are needed to establish the efficacy of these materials as adjuncts to fusion.

Determinants of perioperative transfusion risk in patients with adult spinal deformity

OBJECTIVE

To determine predictors of perioperative allogeneic packed red blood cell (pRBC) transfusion requirement (total units transfused) in patients with adult spinal deformity (ASD).

METHODS

The authors retrospectively analyzed records of patients aged 18 years or older who underwent surgical correction of ASD that involved 4 or more spinal levels by the same spine surgeon between 2010 and 2016. Data regarding patient characteristics, comorbidities, surgical factors, and perioperative transfusions (up to 10 days after surgery) were analyzed using a linear regression model. Significance was set at p < 0.05.

RESULTS

The authors analyzed 165 patients (118 women) with a mean (± SD) age of 61 ± 12 years. Three-column osteotomies were associated with a mean intraoperative transfusion volume of 1.74 additional units of pRBCs. Each unit of intraoperatively salvaged blood used was associated with a mean 0.39-U increase in postoperative transfusion volume (p = 0.031). Every unit of allogeneic blood transfused intraoperatively was associated with a mean 0.23-U decrease in postoperative transfusion volume (p = 0.001). A preoperative hemoglobin concentration of 11.5 g/dl or more was associated with significantly fewer units transfused intraoperatively; a preoperative hemoglobin concentration of 14.0 g/dl or more was associated with fewer units transfused postoperatively. A history of smoking and intraoperative antifibrinolytic use were associated with increased and decreased numbers of units transfused postoperatively, respectively.

CONCLUSIONS

Effective blood management is key to perioperative care of patients with ASD. Three-column osteotomies were associated with a greater number of units of blood transfused. When considering postoperative transfusion requirements, surgeons should note that intraoperative blood salvage might be inferior to intraoperative allogeneic blood transfusion. Using antifibrinolytics and increasing the preoperative hemoglobin concentration to 11.5 g/dl or more are strategies for decreasing the need for perioperative transfusion. A history of smoking is a risk factor for postoperative transfusion requirement (total units transfused).

Do Former Smokers Exhibit a Distinct Profile Before and After Lumbar Spine Surgery?

STUDY DESIGN

Retrospective longitudinal cohort.

OBJECTIVES

To determine if former smokers undergoing lumbar spine surgery have distinct baseline and postoperative patient-reported outcomes (PROs) compared with never smokers and current smokers.

SUMMARY OF BACKGROUND DATA

Smoking has known deleterious effects on patients undergoing lumbar spine surgery. However, former smokers have not been extensively evaluated. There are few studies regarding the relationship between pack-years or duration of smoking cessation, and subsequent clinical outcome.

METHODS

Patients undergoing lumbar spine surgery at three Quality Outcomes Database participating sites were identified. Demographic, surgical and PRO data including pre-op and 12-month post-op back and leg pain scores, Oswestry Disability Index (ODI) and EuroQOL-5D were collected. Smoking status was assessed from individual medical records. Three cohorts, never smokers, former smokers and current smokers, were compared. Association between PROs and quantitative smoking history and duration of pre-op smoking cessation were evaluated in the former smokers.

RESULTS

Of 1187 eligible cases, 843 (71%) had complete data, with 477 never, 250 former, and 116 current smokers. Among patients who had a fusion, baseline and 12-month post-op PROs were significantly different between cohorts, with former smokers having intermediate scores between current and never smokers. In the decompression only group, 12-month ODI was worse in the Current smokers, but overall the effects were much less pronounced. There was a significant negative correlation between smoke-free days before surgery and baseline back pain, ODI, 12-month leg pain and ODI and improvement in ODI. However, the correlation coefficients were small.

CONCLUSION

Former smokers have distinct baseline and 12-month post-op PROs that are intermediate between those of never smokers and current smokers. Smoking cessation does not entirely mitigate the negative effects of smoking on baseline and postoperative PROs for patients undergoing lumbar fusion surgery. This effect is less pronounced in patients undergoing decompression alone.

LEVEL OF EVIDENCE

2.

Risk factors for predicting increased surgical drain output in patients after anterior cervical corpectomy and fusion

Background

Although measures to reduce and treat the postoperative surgical drain output are discussed, along with the increased interest in causative factors related to the prevention and treatment reported by many studies, these are still controversial.

Methods

A retrospective study was conducted on a consecutive series of 217 patients who had underwent ACCF between January 2016 and March 2017. Patients were categorized based on normal or increased total drain output. These two groups were compared for demographic distribution and clinical data to investigate the predictive factors of increased drain output by multivariate analysis.

Results

The overall incidence rate of increased drain output after ACCF was 16.6%. There are no significant differences in sex, BMI, history of taking aspirin, and ASA classification between the two groups (P > 0.05). Of the patients with increased drain output, a significantly higher proportion of patients have OPLL in the surgical level, 18 (50.0%) versus 33 (18.2%) (P = 0.000). The mean age was 60.67 ± 8.18 years versus 54.41 ± 10.05 years (P = 0.001). Number of discs involved was 2.42 ± 0.50 versus 2.02 ± 0.65 (P = 0.001). Operation time was 112.22 ± 16.49 min versus 105.21 ± 17.89 min (P = 0.031). Intraoperative blood loss was 109.86 ± 62.02 mL versus 87.83 ± 56.40 mL (P = 0.036). Logistic regression analysis showed that age (OR, 1.075; p = 0.003), history of smoking (OR, 2.792; p = 0.021), OPLL in surgical level (OR, 2.107; p = 0.001), and number of discs involved (OR, 2.764; p = 0.003) maintained its significance in predicting likelihood of increased surgical drain output.

Conclusions

The occurrence of increased drain output after ACCF is most likely multifactorial and is related to age, history of smoking, OPLL in surgical level, and number of discs involved.

Reduced Impact of Smoking Status on 30-Day Complication and Readmission Rates After Elective Spinal Fusion (≥3 Levels) for Adult Spine Deformity: A Single Institutional Study of 839 Patients

BACKGROUND

Smoking status has been shown to affect postoperative outcomes after surgery. The aim of this study was to determine whether patients' smoking status impacts 30-day complication and readmission rates after elective complex spinal fusion (≥3 levels).

METHODS

The medical records of 839 adult spinal deformity patients undergoing elective complex spinal fusion (≥3 levels) at a major academic institution from 2005 to 2015 were reviewed. We identified 124 (14.8%) smokers and 715 (85.2%) nonsmokers. Patient demographics, comorbidities, intraoperative and postoperative complications, and 30-day readmission rates were collected for each patient. The primary outcome investigated in this study was the rate of 30-day postoperative complication and readmission rates.

RESULTS

Patient demographics and comorbidities were similar between both groups, including age, sex, and body mass index. Median [interquartile] number of fusion levels and operative time were similar between the cohorts (smoker: 5 [4-7] vs. nonsmoker: 5 [4-8], P = 0.58) and (smoker: 309.6 ± 157.9 minutes vs. nonsmoker: 287.5 ± 131.7 minutes, P = 0.16), respectively. Both cohorts had similar postoperative complication rates and lengths of hospital stay. There was no significant difference in 30-day readmission between the cohorts (smoker: 12.9% vs. nonsmoker: 10.8%, P = 0.48). There were no observed differences in 30-day complication rates, including pain (P = 0.46), UTI (P = 0.54), hardware failure (P = 0.36), wound dehiscence (P = 0.29), and wound drainage (P = 0.86). Smokers had greater rates of 30-day cellulitis (smoker: 1.6% vs. nonsmoker: 0.3%, P = 0.05) and DVT (smoker: 0.8% vs. nonsmoker: 0.0%, P = 0.02).

CONCLUSIONS

Our study suggests that smoking does not significantly affect 30-day readmission rates after complex spinal surgery requiring ≥3 levels of fusion. Further studies are necessary to corroborate our findings.

Association Between Allogeneic Blood Transfusion and Postoperative Infection in Major Spine Surgery

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The objective of this study is to compare the incidence of infection in patients who do and do not receive blood transfusions in major deformity surgery (>8 levels).

SUMMARY OF BACKGROUND DATA

Postoperative infections increase morbidity and mortality rates in spine surgery and generate additional costs for the health care system. It has been proposed that blood transfusions increase the risk of wound infection, urinary tract infection, pneumonia, and sepsis.

METHODS

A total of 56 patients met the study criteria, receiving spine surgery involving the fusion of 8 levels or more. Patient-specific characteristics, starting and ending hematocrits, number of units transfused and infections including urinary tract infection, wound infection, pneumonia, and sepsis were documented. Differences in infection risk between those who did and did not undergo a transfusion and their 95% confidence intervals were calculated.

RESULTS

Groups were similar with respect to baseline and surgical characteristics except for smoking status, operative time, estimated blood loss, and ending hematocrit. The overall infection rate was greater in patients who underwent transfusion than those who did not (36% vs. 10%; P=0.03). Wound infections (n=5) were only observed in those who underwent a transfusion. Smokers were more likely to receive a transfusion and more likely to experience infection. A stratified analysis demonstrated an increased risk of infection associated with transfusion; however, the risk was greater in smokers, suggesting the effect of transfusion on infection could be modified by smoking. Patients undergoing transfusion experienced a significantly longer hospital stay (P=0.01).

CONCLUSIONS

Allogeneic red blood cell transfusion in major spine surgery could be a risk factor for postoperative infection. This increased risk seems to be magnified in those who smoke. Further studies are warranted, and risks of blood loss and transfusion-related complications in smokers also potentially merit exploration.

LEVEL OF EVIDENCE

Level 3.

Incidence and Risk Factors of Postoperative Hematoma Requiring Reoperation in Single-level Lumbar Fusion Surgery

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

The purpose of the present study was to examine the incidence and risk factors for postoperative hematoma requiring reoperation in patients undergoing single-level lumbar fusion surgery.

SUMMARY OF BACKGROUND DATA

Postoperative hematoma can cause devastating neurological consequences after spine surgery. Risk factors for hematoma in specific spine procedures have not been well established.

METHODS

A cohort of patients undergoing single-level lumbar fusion surgery was constructed from the 2012 to 2013 American College of Surgeons National Surgical Quality Improvement Program dataset using Current Procedural Terminology codes (22533, 22558, 22612, 22630, and 22633). In cases requiring reoperation within 30 days after initial surgery, postoperative hematoma was identified using the ICD-9 code 998.1. Risk factors for postoperative hematoma were assessed with logistic regression modeling.

RESULTS

Of 5280 patients undergoing single-level lumbar fusion surgery, 27 patients (0.5%) developed a postoperative hematoma requiring reoperation for hematoma evacuation. A heightened incidence of postoperative hematoma was found in patients who were smokers (1.0% vs. 0.4% for nonsmokers, P = 0.016) or who had a diagnosis of bleeding disorder (3.8% vs. 0.5% for those without bleeding disorder, P = 0.007). Multivariate logistic regression analysis indicated that the adjusted odds ratios for postoperative hematoma associated with smoking and bleeding disorder were 3.34 (95% confidence interval, 1.15-9.71) and 10.2 (95% confidence interval, 1.9-54.8), respectively.

CONCLUSION

Smoking and bleeding disorder appear to be major risk factors for postoperative hematoma requiring reoperation after single-level lumbar fusion surgery. Intervention programs targeting patients with these risk factors are needed to reduce their excess risk of postoperative hematoma.

LEVEL OF EVIDENCE

3.

Risk Factors for 30-Day Unplanned Readmission and Major Perioperative Complications After Spine Fusion Surgery in Adults: A Review of the National Surgical Quality Improvement Program Database

STUDY DESIGN

Retrospective review of a prospective cohort.

OBJECTIVE

The aim of the study was to determine the patient characteristics and surgical procedure factors related to increased rates of 30-day unplanned readmission and major perioperative complications after spinal fusion surgery, and the association between unplanned readmission and major complications.

SUMMARY OF BACKGROUND DATA

Reducing unplanned readmissions can reduce the cost of healthcare. Payers are implementing penalties for 30-day readmissions after discharge. There is limited data regarding the current rates and risk factors for unplanned readmission and major complications related to spinal fusion surgery.

METHODS

Spine fusion patients were identified using the 2012 and 2013 American College of Surgeons National Surgical Quality Improvement Program Participant User File. Rates of readmissions within 30 days after spine fusion surgery were calculated using the person-years method. Cox proportional hazards models were used to assess the independent associations of spine surgical procedure types, diagnoses, patient profiles, and major perioperative complications with unplanned related readmissions. Independent risk factors for major complications were assessed by multivariable logistic regression.

RESULTS

Of the 18,602 identified patients, there was a 5.2% overall major perioperative complication rate. There was a rate of 4.4% per 30 person-days for unplanned readmissions related to index surgery. Independent risk factors for both readmissions and major perioperative complications included combined anterior and posterior surgery, diagnosis of solitary tumor, older age, and higher American Society of Anesthesiologists class. Patients with deep/organ surgical site infection carried higher risk of having unplanned readmission, followed by pulmonary embolism, acute renal failure, and stroke/cerebral vascular accident with neurological deficit.

CONCLUSION

This study provides benchmark rates of 30-day readmission based on diagnosis and procedure codes from a high-quality database for adult spinal fusion patients and showed increased rates of 30-day unplanned readmission and major perioperative complications for patients with specific risk factors. Targeted preoperative planning on modifiable risk factors with proportional reimbursement may promote higher-quality healthcare.

LEVEL OF EVIDENCE

3.