Multivariate analysis of incision infection after posterior lumbar surgery in diabetic patients: A single-center retrospective analysis

Association of Elevated Perioperative Blood Glucose With Complications and Postoperative Outcomes Following Traumatic Spine Surgery

BACKGROUND

Perioperative blood glucose control has been demonstrated to influence outcomes following spine surgery, though this association has not been fully elucidated in patients with traumatic spine injuries. This study sought to determine the association between perioperative blood glucose levels and complications or outcomes in patients undergoing spine surgery due to injury.

METHODS

A retrospective review was conducted to identify patients who underwent spine surgery due to traumatic injuries between 1 March 2020 and 29 September 2022 at a single academic institution. Descriptive factors, complications, and outcomes were compared between those with a postoperative blood glucose level of <200 mg/dL and those with a preoperative glucose of <200 mg/dL.

RESULTS

Patients with a post- and preoperative blood glucose of ≥200 mg/dL had significantly higher odds of respiratory complications (OR = 2.1, 2.1, P = 0.02, 0.03), skin/wound complications (OR = 2.2, 2.8, P = 0.04, 0.03), and increased hospital length of stay (OR = 9.6, 12.1, P = 0.02, 0.03) compared with those with blood glucose of <200 mg/dL. Those with postoperative glucose ≥200 mg/dL also had significantly higher odds of inpatient mortality (OR = 4.5, P = 0.04) when controlling for confounding factors. Neither pre- nor postoperative blood glucose of ≥200 mg/dL was associated with an improvement in American Spinal Injury Association Impairment Scale score at the final follow-up when controlling for multiple confounding factors (P = 0.44, 0.06).

CONCLUSION

Elevated blood glucose both pre- and postoperatively was associated with an increased rate of postoperative complications and negative postoperative outcomes. However, there was no association between elevated blood glucose levels and neurological recovery following traumatic spinal injury.

LEVEL OF EVIDENCE: 3

Prediction models for risk assessment of surgical site infection after spinal surgery: A systematic review

Background

Spinal surgeries are a common procedure, but there is significant risk of adverse events following these operations. While the rate of adverse events ranges from 8% to 18%, surgical site infections (SSIs) alone occur in between 1% and 4% of spinal surgeries.

Methods

We completed a systematic review addressing factors that contribute to surgical site infection after spinal surgery. From the included studies, we separated the articles into groups based on whether they propose a clinical predictive tool or model. We then compared the prediction variables, model development, model validation, and model performance.

Results

About 47 articles were included in this study: 10 proposed a model and 5 validated a model. The models were developed from 7,720 participants in total and 210 participants with SSI. Only one of the proposed models was externally validated by an independent group. The other 4 validation papers examined the performance of the ACS NSQIP surgical risk calculator.

Conclusions

While some preoperative risk models have been validated, and even successfully implemented clinically, the significance of postoperative SSIs and the unique susceptibility of spine surgery patients merits the development of a spine-specific preoperative risk model. Additionally, comprehensive and stratified risk modeling for SSI would be of invaluable clinical utility and greatly improve the field of spine surgery.

The Effects of Blood Glucose Control in the Operative Spine Patient: A Systematic Review

OBJECTIVE

To our knowledge, this is the first systematic review to evaluate the available literature on the effects of perioperative serum glucose (SG) on outcomes for patients undergoing spine surgery. This review will add insight into how the perioperative management of SG affects the outcomes of patients undergoing spine surgery.

METHODS

Three databases were used in this review including Embase, PubMed, and Cochrane Library. The searches were from 2012 to 2022 and included the terms "spine surgery" and "glucose level" to identify studies that demonstrated a correlation between glucose level and postoperative outcomes. Pediatric studies, those that did not specify spine surgical outcomes related to glucose levels, and non-English studies were excluded. The methodological items for nonrandomized studies score was used to assess risk of bias in the included studies.

RESULTS

This review included a total of 9 cohort studies, both prospective and retrospective, encompassing a total of 431,156 subjects. Seven of the 9 studies reported an increased overall complication rate among patients with diabetes or with higher SG levels, and 4 studies demonstrated an increased infection rate among this population. Two studies reported an association between decreased SG levels and improved neurological recovery when a deficit was present preoperatively, and 1 of the studies found that this association was statistically significant.

LIMITATIONS

Limitations of this review include lack of standardization regarding type of surgery, location of the spine, and level of evidence.

CONCLUSION

Most of the current literature suggests that elevated SG levels in patients undergoing spine surgery likely leads to higher complication rates and may lead to increased infection rates, and this review reinforced the current evidence. Additionally, perioperative SG levels may be associated with the extent of neurological recovery after surgery, but further investigation may be warranted.

CLINICAL RELEVANCE

This review adds to the current body of evidence regarding perioperative SG levels and its association with complications.

LEVEL OF EVIDENCE: 2

Construction and validation of a nomogram prediction model for postoperative incisional infection in ankle fractures

The aim was to investigate the independent risk factors for postoperative incisional infection in ankle fractures and to establish a nomogram prediction model accordingly. Data were collected from ankle fracture patients in the Affiliated Hospital of Xinjiang Medical University from January 2018 to December 2022. Univariate and multivariate logistic regression analyses were used to determine the independent risk factors for postoperative incisional infection in ankle fractures and to establish the corresponding nomogram. Receiver operating characteristic curves were plotted and area under the curve was calculated, and calibration curves and decision curve analysis were plotted to evaluate the model performance. A total of 722 patients with ankle fractures were included in the study, and 76 patients developed postoperative incisional infections, with an incidence of 10.53%. After univariate and multivariate logistic regression analysis, a total of 5 variables were identified as independent risk factors for postoperative incisional infection in ankle fractures, namely, age ≥ 60 years (OR, 1.885; 95% CI, 1.156-3.045), having diabetes (OR1.625; 95% CI, 1.095-2.876), open fracture (OR, 5.564; 95% CI, 3.099-9.990), albumin < 35 g/L (OR, 2.618; 95% CI, 1.217-4.215), and operative time ≥ 2 hours (OR, 1.606; 95% CI, 1.077-3.247). The nomogram for postoperative incisional infection after ankle fracture constructed in this study has good predictive accuracy and helps orthopedic surgeons to intervene earlier in patients at high risk of postoperative incisional infection after ankle fracture.

The Effect of a Checklist for Perioperative Hyperglycemia Management on Surgical Site Infections: A Randomized Controlled Trial

PURPOSE

This study was conducted to evaluate the effect of managing perioperative normoglycemia using a structured and standardized normoglycemia checklist on surgical site infection (SSI).

DESIGN

The study is a prospective randomized controlled experimental case-control study.

METHODS

A normoglycemia checklist was applied to the patients selected for the experimental group preoperatively, intraoperatively, and postoperatively (continuous insulin infusion applied to keep the blood glucose level within the range of 80 to 150 mg/dl until 48 hours postoperative) according to their blood glucose levels. The routine practice available in the clinic was applied to the control group.

FINDINGS

The rate of SSI development in the control group (27.5%) was significantly higher than in the experimental group (2.5%) (P < .05). The culture was examined only in patients with deep incisional SSI, and E. Coli and Gram (-) Bacillus were the most prolific microorganisms. The risk of re-hospitalization of the control group patients was 2 times higher than the experimental group (P < .05).

CONCLUSIONS

This study reports the prevalence, diagnosis, and pathophysiology of perioperative hyperglycemia in patients undergoing cholecystectomy and provides a practical method for the management of blood glucose levels in surgery patients diagnosed with diabetes mellitus and developing stress hyperglycemia.

Management of Hyperglycemia in Hospitalized Adult Patients in Non-Critical Care Settings: An Endocrine Society Clinical Practice Guideline

BACKGROUND

Adult patients with diabetes or newly recognized hyperglycemia account for over 30% of noncritically ill hospitalized patients. These patients are at increased risk for adverse clinical outcomes in the absence of defined approaches to glycemic management.

OBJECTIVE

To review and update the 2012 Management of Hyperglycemia in Hospitalized Patients in Non-Critical Care Settings: An Endocrine Society Clinical Practice Guideline and to address emerging areas specific to the target population of noncritically ill hospitalized patients with diabetes or newly recognized or stress-induced hyperglycemia.

METHODS

A multidisciplinary panel of clinician experts, together with a patient representative and experts in systematic reviews and guideline development, identified and prioritized 10 clinical questions related to inpatient management of patients with diabetes and/or hyperglycemia. The systematic reviews queried electronic databases for studies relevant to the selected questions. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology was used to assess the certainty of evidence and make recommendations.

RESULTS

The panel agreed on 10 frequently encountered areas specific to glycemic management in the hospital for which 15 recommendations were made. The guideline includes conditional recommendations for hospital use of emerging diabetes technologies including continuous glucose monitoring and insulin pump therapy; insulin regimens for prandial insulin dosing, glucocorticoid, and enteral nutrition-associated hyperglycemia; and use of noninsulin therapies. Recommendations were also made for issues relating to preoperative glycemic measures, appropriate use of correctional insulin, and diabetes self-management education in the hospital. A conditional recommendation was made against preoperative use of caloric beverages in patients with diabetes.

CONCLUSION

The recommendations are based on the consideration of important outcomes, practicality, feasibility, and patient values and preferences. These recommendations can be used to inform system improvement and clinical practice for this frequently encountered inpatient population.

A Systematic Review Supporting the Endocrine Society Clinical Practice Guideline for the Management of Hyperglycemia in Adults Hospitalized for Noncritical Illness or Undergoing Elective Surgical Procedures

CONTEXT

Individuals with diabetes or newly recognized hyperglycemia account for over 30% of noncritically ill hospitalized patients. Management of hyperglycemia in these patients is challenging.

OBJECTIVE

To support development of the Endocrine Society Clinical Practice Guideline for management of hyperglycemia in adults hospitalized for noncritical illness or undergoing elective surgical procedures.

METHODS

We searched several databases for studies addressing 10 questions provided by a guideline panel from the Endocrine Society. Meta-analysis was conducted when feasible. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology was used to assess certainty of evidence.

RESULTS

We included 94 studies reporting on 135 553 patients. Compared with capillary blood glucose, continuous glucose monitoring increased the number of patients identified with hypoglycemia and decreased mean daily blood glucose (BG) (very low certainty). Data on continuation of insulin pump therapy in hospitalized adults were sparse. In hospitalized patients receiving glucocorticoids, combination neutral protamine hagedorn (NPH) and basal-bolus insulin was associated with lower mean BG compared to basal-bolus insulin alone (very low certainty). Data on NPH insulin vs basal-bolus insulin in hospitalized adults receiving enteral nutrition were inconclusive. Inpatient diabetes education was associated with lower HbA1c at 3 and 6 months after discharge (moderate certainty) and reduced hospital readmissions (very low certainty). Preoperative HbA1c level < 7% was associated with shorter length of stay, lower postoperative BG and a lower number of neurological complications and infections, but a higher number of reoperations (very low certainty). Treatment with glucagon-like peptide-1 agonists or dipeptidyl peptidase-4 inhibitors in hospitalized patients with type 2 diabetes and mild hyperglycemia was associated with lower frequency of hypoglycemic events than insulin therapy (low certainty). Caloric oral fluids before surgery in adults with diabetes undergoing surgical procedures did not affect outcomes (very low certainty). Counting carbohydrates for prandial insulin dosing did not affect outcomes (very low certainty). Compared with scheduled insulin (basal-bolus or basal insulin + correctional insulin), correctional insulin was associated with higher mean daily BG and fewer hypoglycemic events (low certainty).

CONCLUSION

The certainty of evidence supporting many hyperglycemia management decisions is low, emphasizing importance of shared decision-making and consideration of other decisional factors.

A new radiological index for the assessment of higher body fat status and lumbar spine degeneration

OBJECTIVE

Obesity has been proposed as a risk factor for low back pain (LBP) and intervertebral disc degeneration (IVDD). Even though body mass index (BMI) is used as a parameter for obesity, it could not represent percentage and distribution of the body fat. Subcutaneous fat tissue thickness (SFTT) was proposed as one of the magnetic resonance imaging (MRI) parameters to evaluate the percentage of the body fat. In this study, we aimed to find out whether SFTT at lower back correlated with LBP and spine degeneration.

MATERIALS AND METHODS

We retrospectively reviewed a database of the patients with LBP. Concomitantly, asymptomatic control subjects were retrieved. Patients and control subjects were evaluated in terms of IVDD and Modic changes at all lumbar levels on MRI. SFTT was measured both on MRI and computed tomography (CT) scans, where applicable.

RESULTS

SFTT at the lumbar spine had moderate-to-strong correlations with BMI. SFTT at L1-L2 level was significantly associated with severe IVDD at L5-S1 level, and Modic changes at L4-L5 and L5-S1 levels. BMI had no significant association with severe IVDD and Modic changes at lumbar spine. BMI and mean SFTT of all lumbar levels had ORs of 0.735 (95% CI: 0.631-0.857, p < 0.001) and 1.389 (95% CI: 1.266-1.524, p < 0.001) in predicting symptomatic subjects with LBP.

CONCLUSION

SFTT at upper lumbar levels could predict severe IVDD and Modic changes better than BMI, specifically in men. SFTT was better than BMI in predicting a symptomatic patient with LBP.

Postoperative Glycemic Variability as a Predictor of Adverse Outcomes Following Lumbar Fusion

STUDY DESIGN

A retrospective cross-sectional study.

OBJECTIVE

This study aims to evaluate the effect size of postoperative glycemic variability on surgical outcomes among patients who have undergone one- to three-level lumbar fusion.

SUMMARY OF BACKGROUND DATA

While numerous patient characteristics have been associated with surgical outcomes after lumbar fusion, recent studies have described the measuring of postoperative glycemic variability as another promising marker.

METHODS

A total of 850 patients were stratified into tertiles (low, moderate, high) based on degree of postoperative glycemic variability defined by coefficient of variation (CV). Surgical site infections were determined via chart review based on the Centers for Disease Control and Prevention definition. Demographic factors, surgical characteristics, inpatient complications, readmissions, and reoperations were determined by chart review and telephone encounters.

RESULTS

Overall, a statistically significant difference in 90-day adverse outcomes was observed when stratified by postoperative glycemic variability. In particular, patients with high CV had a higher odds ratio (OR) of readmission (OR = 2.19 [1.17, 4.09]; P = 0.01), experiencing a surgical site infection (OR = 3.22 [1.39, 7.45]; P = 0.01), and undergoing reoperations (OR = 2.65 [1.34, 5.23]; P = 0.01) compared with patients with low CV. No significant association was seen between low and moderate CV groups. Higher CV patients were more likely to experience longer hospital stays (β: 1.03; P = 0.01). Among the three groups, high CV group experienced the highest proportion of complications.

CONCLUSION

Our study establishes a significant relationship between postoperative glycemic variability and inpatient complications, length of stay, and 90-day adverse outcomes. While HbA1c has classically been used as the principal marker to assess blood glucose control, our results show CV to be a strong predictor of postoperative adverse outcomes. Future high-quality, prospective studies are necessary to explore the true effect of CV, as well as its practicality in clinical practice. Nevertheless, fluctuations in blood glucose levels during the inpatient stay should be limited to improve patient results.Level of Evidence: 4.

Association of Preoperative Hemoglobin A1c and Body Mass Index with Wound Infection Rate in Spinal Surgery

BACKGROUND

The deleterious effect of diabetes mellitus on surgical outcomes is well documented for joint replacement surgery. We analyzed the large national US Department of Veterans Affairs (VA) database for patients who had undergone elective spinal surgery.

METHODS

We retrospectively searched the VA database and identified 174 520 spine cases.

RESULTS

There were 7766 (4.5%) wound infections and 49 271 (28%) had hemoglobin A1c (HbA1c) testing (range: 3.0-17.8) prior to surgery. In the preoperative HbA1c-checked group, there were 2941 (6.0% of 49 271) infections and in the without-preoperative HbA1c group, there were 4825 (3.9% of 125 249) infections. The distribution of infections was significantly different (χ² = 372.577, P < .0001) and suggests a 2.12% increase in the absolute risk of infection based on the presence of preoperative HbA1c testing, regardless of the result. Logistic regression revealed a preoperative HbA1c test was associated with an odds ratio of 1.435 for infection (confidence interval 1.367-1.505, P < .0001). In a separate model based on HbA1c levels, we found that HbA1c is a significant predictor of infection with an odds ratio of 1.042 (confidence interval 1.017-1.068, P = .0009) for each 1% increase in the test result. This analysis differs from using a strict cutoff value of HbA1c of 6.5%. Similar testing for body mass index and age yielded an odds ratio of 1.027 for each increase of 1 kg/m² and an odds ratio of 1.009 for each 1-year increase in age respectively.

CONCLUSIONS

Hemoglobin A1c testing, HgA1c value, body mass index, and age all contribute to the risk of wound infection after elective spine surgery in a large national VA population. These data can be used to estimate surgical risks and to aid in patient counseling about proposed spine surgery.

LEVEL OF EVIDENCE

4.

Postoperative Glycemic Variability and Adverse Outcomes After Posterior Cervical Fusion

INTRODUCTION

Posterior cervical decompression and fusion (PCDF) is a procedure commonly performed to help alleviate symptoms and improve quality of life in patients experiencing cervical spondylotic myelopathy, multilevel stenosis, and cervical deformity. Although various risk factors have been linked to adverse outcomes in patients after PCDF, this is the first study that specifically explores postoperative glycemic variability and its association with adverse outcomes.

METHODS

A retrospective cohort study was conducted with a total of 264 patients after PCDF procedures that had available postoperative blood glucose measurements. Patients were divided into tertiles based on their coefficient of variation as an indicator of glycemic variability. Outcomes measured included inpatient complications, length of stay (LOS), 90-day readmission, revision, and surgical site infection rates.

RESULTS

Results showed a significant difference in glycemic variability among tertiles with respect to LOS (P = 0.01). The average LOS for the first, second, and third tertiles was 3.90 (3.20, 4.59), 5.73 (4.45, 7.00), and 6.06 (4.89, 7.22), respectively. Logistic regression analysis showed significantly higher odds of readmission (odds ratio: 4.77; P = 0.03) and surgical site infections (odds ratio: 4.35; P = 0.04) in the high glycemic variability group compared with the low glycemic variability group within 90 days of surgery. No significant difference was noted among tertiles with respect to inpatient complications.

DISCUSSION

This study establishes a relationship between postoperative glycemic variability and LOS, as well as 90-day readmission and surgical site infection rates after PCDF. Our results suggest that limiting fluctuations in blood glucose levels may curtail inpatient healthcare costs related to in-hospital stay. Although immediate postoperative glycemic variability is ultimately acceptable, before discharge, proper glucose management plans should be in place to help prevent adverse patient outcomes.

Smoking increases the risk of infectious diseases: A narrative review

Smoking is relevant to infectious diseases resulting in increased prevalence and mortality. In this article, we aim to provide an overview of the effects of smoking in various infections and to explain the potential mechanisms. We searched PubMed and other relevant databases for scientific studies that explored the relationship between smoking and infection. The mechanisms of susceptibility to infection in smokers may include alteration of the structural, functional and immunologic host defences. Smoking is one of the main risk factors for infections in the respiratory tract, digestive tract, reproductive tract, and other systems in humans, increasing the prevalence of HIV, tuberculosis, SARS-CoV, and the current SARS-CoV-2. Smoking cessation can reduce the risk of infection. Smoking increases the incidence of infections and aggravates the progress and prognosis of infectious diseases in a dose-dependent manner. Smoking cessation promotion and education are the most practical and economical preventive measures to reduce aggravation of disease infection owing to tobacco use.