Lymphocyte Count at 4 Days Postoperatively and CRP Level at 7 Days Postoperatively: Reliable and Useful Markers for Surgical Site Infection Following Instrumented Spinal Fusion

Efficacy of Antibiotic Bone Cement in the Treatment of Burkholderia cepacia Infection After Spinal Internal Fixation Surgery: Case Report and Literature Review

BACKGROUND

In recent years, the number of spinal internal fixation operations has increased significantly, correlating with an elevated risk of postoperative surgical site infection and a rising incidence rate. While the conventional treatment approach involves surgical debridement combined with antibiotic administration, there is a notable gap in reported strategies for Burkholderia cepacia infection and patients exhibiting multidrug resistance.

METHODS

Surgical site infection occurred in a patient following internal fixation surgery for thoracic vertebral fractures. Despite the application of systemic antibiotics and regular dressing changes, no improvement was observed. Bacterial culture and drug sensitivity experiments revealed a multidrug-resistant Burkholderia cepacia infection. Two comprehensive debridement procedures were performed along with continuous post-operative irrigation combined with antibiotic administration; however, no significant improvement was observed. The patient's infection was significantly controlled following treatment with vancomycin loaded bone cement.

RESULTS

Following spinal internal fixation surgery, the management of a B. cepacian infection with multidrug resistance presented a significant challenge, despite the application of debridement procedures and systemic antibiotics. In this case, after 20 days of treatment with vancomycin-loaded bone cement, the patient's C-reactive protein level decreased to 54 mg/L, was normalized by February, and normal levels were maintained in the surgical area 1 month and 6 months after bone cement removal.

CONCLUSIONS

The use of vancomycin-loaded bone cement proves effective in treating postoperative B. cepacian infection in a multidrug-resistant case following spinal internal fixation surgery.

Short-term clinical efficacy and safety of unilateral biportal endoscopic transforaminal lumbar interbody fusion versus minimally invasive transforaminal lumbar interbody fusion in the treatment of lumbar degenerative diseases: a systematic review and meta-analysis

BACKGROUND

The aim of this study was to comprehensively evaluate the short-term clinical efficacy and safety of unilateral biportal endoscopic transforaminal lumbar interbody fusion (UBE-TLIF) versus minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for the treatment of lumbar degenerative diseases by meta-analysis.

METHODS

A computer-based search of PubMed, Embase, Web of Science, Cochrane Database, China National Knowledge Infrastructure (CNKI), Wanfang Database, and Chinese Science and Technology Journal Database (VIP) was conducted from the inception of the each database to April 2023. The searched literature was then screened according to strict inclusion and exclusion criteria. The critical data were extracted and analyzed using Review Manager software5.4.1. Pooled effects were calculated on the basis of data attributes by mean difference (MD) or odds ratio (OR) with 95% confidence interval (CI). The Newcastle-Ottawa Scale was used to assess the quality of the studies.

RESULTS

A total of 13 studies and 949 patients met the inclusion criteria for this meta-analysis, 445 in the UBE-LIF group and 504 in the MIS-TLIF group. UBE-TLIF was superior to MIS-TLIF in terms of intraoperative blood flow, postoperative drainage flow, duration of hospital stay, VAS score for low back pain and ODI score, but the operative time was longer than MIS-TLIF group. There were no significant differences between the two groups in terms of total complication rate, modified Macnab grading criteria, fusion rate, VAS score of leg pain, lumbar lordosis, intervertebral disk height.

CONCLUSION

Both UBE-TLIF and MIS-TLIF are effective surgical modalities for the treatment of degenerative lumbar spine diseases. They have similar treatment outcomes, but UBE-TLIF has the advantages of less intraoperative blood loss, shorter postoperative hospital stay, and faster recovery.

TRIAL REGISTRATION

This study has been registered at INPLASY.COM (No. INPLASY202320087).

Using multiple indicators to predict the risk of surgical site infection after ORIF of tibia fractures: a machine learning based study

Objective

Surgical site infection (SSI) are a serious complication that can occur after open reduction and internal fixation (ORIF) of tibial fractures, leading to severe consequences. This study aimed to develop a machine learning (ML)-based predictive model to screen high-risk patients of SSI following ORIF of tibial fractures, thereby aiding in personalized prevention and treatment.

Methods

Patients who underwent ORIF of tibial fractures between January 2018 and October 2022 at the Department of Emergency Trauma Surgery at Ganzhou People's Hospital were retrospectively included. The demographic characteristics, surgery-related variables and laboratory indicators of patients were collected in the inpatient electronic medical records. Ten different machine learning algorithms were employed to develop the prediction model, and the performance of the models was evaluated to select the best predictive model. Ten-fold cross validation for the training set and ROC curves for the test set were used to evaluate model performance. The decision curve and calibration curve analysis were used to verify the clinical value of the model, and the relative importance of features in the model was analyzed.

Results

A total of 351 patients who underwent ORIF of tibia fractures were included in this study, among whom 51 (14.53%) had SSI and 300 (85.47%) did not. Of the patients with SSI, 15 cases were of deep infection, and 36 cases were of superficial infection. Given the initial parameters, the ET, LR and RF are the top three algorithms with excellent performance. Ten-fold cross-validation on the training set and ROC curves on the test set revealed that the ET model had the best performance, with AUC values of 0.853 and 0.866, respectively. The decision curve analysis and calibration curves also showed that the ET model had the best clinical utility. Finally, the performance of the ET model was further tested, and the relative importance of features in the model was analyzed.

Conclusion

In this study, we constructed a multivariate prediction model for SSI after ORIF of tibial fracture through ML, and the strength of this study was the use of multiple indicators to establish an infection prediction model, which can better reflect the real situation of patients, and the model show great clinical prediction performance.

Comparison of surgical invasiveness, hidden blood loss, and clinical outcome between unilateral biportal endoscopic and minimally invasive transforaminal lumbar interbody fusion for lumbar degenerative disease: a retrospective cohort study

BACKGROUND

Currently, hidden blood loss (HBL) has been paid more and more attention by spine surgeons. Simultaneously, it has been the effort of spine surgeons to explore more advantages of minimally invasive surgery. More and more articles have compared unilateral biportal endoscopic lumbar interbody fusion (BE-LIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). But so far, there is no HBL comparison between BE-LIF and MIS-TLIF. This study aims to compare the surgical invasiveness, hidden blood loss, and clinical outcome of BE-LIF and MIS-TLIF and to provide insight regarding minimally invasive surgery for lumbar degenerative disease (LDD).

METHODS

We enrolled 103 eligible patients with LDD who underwent BE-LIF (n = 46) and MIS-TLIF (n = 57) during August 2020-March 2021. We collected data, including demographics, perioperative haematocrit, operative and postoperative hospital times, serum creatine kinase (CK) and C-reactive protein (CRP) levels, and hospitalization costs. Total and hidden blood loss was calculated. Clinical outcomes were assessed using a visual analogue scale (VAS) score for back and leg pain, Oswestry Disability Index (ODI), modified MacNab criteria, fusion rate, and complications.

RESULTS

Basic demographics and surgical data were comparable. The CRP and CK levels were generally lower in the BE-LIF than in the MIS-TLIF group, especially CRP levels on postoperative day (POD) three and CK levels on POD one. True total blood loss, postoperative blood loss, and hidden blood loss were significantly reduced in the BE-LIF group compared with the MIS-TLIF group. Postoperative hospital times was statistically significantly shorter in the BE-LIF group. The VAS pain and ODI scores improved in both groups. At three days and one month, the VAS lower back pain scores were significantly better after BE-LIF. Clinical outcomes did not otherwise differ between groups.

CONCLUSIONS

Compared with MIS-TLIF, BE-LIF has similar medium and short-term clinical outcomes. However, it is better regarding surgical trauma, early lower back pain, total and hidden blood loss, and recovery time. BE-LIF is an adequate option for selected LDD.

C-reactive protein to lymphocyte ratio as a new biomarker in predicting surgical site infection after posterior lumbar interbody fusion and instrumentation

Purpose

This study aims to evaluate the potential of C-reactive protein to lymphocyte count ratio (CLR) for the prediction of surgical site infection (SSI) following posterior lumbar interbody fusion (PLIF) and the instrumentation of lumbar degenerative diseases.

Methods

In this retrospective study, we considered patients with a lumbar degenerative disease diagnosis surgically treated by the instrumented PLIF procedure from 2015 to 2021. Patient data, including postoperative early SSI and other perioperative variables, were collected from their respective hospitalization electronic medical records. The receiver operator characteristic curve was constructed to determine the optimal cut-off value for CLR, and the ability to predict SSI was evaluated by the area under the curve (AUC). According to the cut-off value, patients were dichotomized with high- or low-CLR, and between-group differences were compared using univariate analysis. The independent impact of CLR on predicting SSI was investigated by multivariate logistics regression analysis.

Results

A total of 773 patients were included, with 26 (3.4%) developing an early SSI post-operation. The preoperative CLR was 11.1 ± 26.1 (interquartile range, 0.4–7.5), and the optimal cut-off was 2.1, corresponding to a sensitivity of 0.856, a specificity of 0.643, and an AUC of 0.768 (95% CI, 0.737–0.797). CLR demonstrated a significantly improved prediction ability than did lymphocyte count (P = 0.021) and a similar ability to predict an infection as C-response protein (P = 0.444). Patients with a high CLR had a significantly higher SSI incidence than those with a low CLR (7.6% vs. 0.8%, P < 0.001). After adjustment for numerous confounding factors, CLR ≥ 2.1 was associated with an 11.16-fold increased risk of SSI, along with other significant variables, i.e., diabetes, preoperative waiting time, and surgical duration.

Conclusion

A high CLR exhibited an improved ability to predict incident SSI and was associated with a substantially increased risk of SSI following instrumented PLIF. After better-design studies verified this finding, CLR could potentially be a beneficial tool in surgical management.

Preoperative Lymphocyte to Monocyte Ratio as a Predictive Biomarker for Disease Severity and Spinal Fusion Failure in Lumbar Degenerative Diseases Patients Undergoing Lumbar Fusion

Objective

This study was designed to determine whether lymphocyte to monocyte ratio (LMR) correlated with the intervertebral disc degeneration (IDD) severity and the postoperative spinal fusion rate in patients with lumbar disc disease.

Methods

303 patients undergoing posterior lumbar decompression and fusion were retrospectively analyzed. An examination of the blood count was performed before surgery. The cumulative grade was calculated by summing the pfirrmann grades of all lumbar discs. Grouping was based on the 50th percentile of cumulative grade and spinal fusion. The relationship between LMR and IDD severity and spinal fusion was explored using correlation analyses and logistic regression models. The receiver operating characteristic (ROC) curve was performed to measure model discrimination, and Hosmer-Lemeshow (H-L) test was used to measure calibration. Meanwhile, the ROC curve evaluated the discrimination ability of LMR in predicting severe degeneration and fusion failure.

Results

LMR was significantly lower in the severe degeneration group (cumulative grade > 18) than in the mild to moderate degeneration group (cumulative grade ≤ 18). Furthermore, the LMR of the fusion group was significantly higher than that of the non-fusion group. The multivariate binary logistic models revealed that LMR was an independently influencing factor of the severe degeneration and fusion failure (OR: 0.793, 95% CI: 0.638–0.987, p = 0.038; OR: 0.371, 95% CI: 0.258–0.532, p < 0.001). The models showed excellent discrimination and calibration. The area under the curve (AUC) of severe degeneration and fusion failure identified by LMR were 0.635 and 0.643, respectively, and the corresponding cut-off values were 3.16 and 3.90.

Conclusion

LMR is significantly associated with the risk of severe disc degeneration and spinal fusion failure.

Temporal Evolution of White Blood Cell Count and Differential: Reliable and Early Detection Markers for Surgical Site Infection Following Spinal Posterior Decompression Surgery

Introduction

For early detection of surgical site infection (SSI) following spinal decompression surgery, we compared temporal changes in the values of laboratory markers that are not affected by operative parameters.

Methods

The study included 302 patients, which were divided into an SSI group (patients who developed deep SSI) and a non-SSI group for analysis. We reviewed data on C-reactive protein level, total white blood cell (WBC) count, and WBC differential percentage and count before spinal decompression, on postoperative day 1, and on postoperative day 4. We identified laboratory markers that are not affected by operative parameters (operating time, intraoperative blood loss, and number of operative segments). Laboratory markers with a significant difference observed between the peak or nadir value and the value in the subsequent survey day were considered as an indicator of SSI. We examined the utility of each indicator by calculating sensitivity and specificity. Furthermore, we investigated the utility of the combination of all five indicators (wherein the recognition of one marker was considered positive).

Results

Temporal changes in five laboratory markers were considered indicators of SSI. The changes from postoperative day 1 to postoperative day 4 were as follows: (1) increased WBC count (42% sensitivity, 88% specificity), (2) increased neutrophil percentage (25% sensitivity, 96% specificity), (3) increased neutrophil count (25% sensitivity, 94% specificity), (4) decreased lymphocyte percentage (25% sensitivity, 95% specificity), and (5) decreased lymphocyte count (25% sensitivity, 85% specificity). The combination of these five markers showed a 50% sensitivity, 81% specificity, and 0.65 AUC.

Conclusions

Five markers were found to be reliable indicators of SSI following spinal decompression surgery because they were not affected by operative parameters. The combination of all five indicators had moderate sensitivity and high specificity. Therefore, this may be reliable and useful for the early detection of SSI.

A novel approach for identifying serological markers indicative of surgical-site infection following spine surgery: Postoperative lymphopenia is a risk factor

BACKGROUND

Postoperative lymphopenia (PL) after spine surgery is reported to be an indicator of surgical-site infection (SSI). PL without SSI is often encountered, resulting in a treatment dilemma. We focused on PL, so as to improve the accuracy of detecting SSI.

METHODS

In total, 329 patients underwent spine surgery, including nine patients presenting with SSI. The complete blood cell counts, differential counts, and C-reactive protein (CRP) level were measured pre-surgery and on postoperative days 2, 7, and 14. The relationships between PL and SSI were evaluated, and PL and non-PL conditions were compared among all cases. We then divided the patients into two groups: PL and non-PL, and determined the useful serological markers using receiver operating characteristic curves.

RESULTS

Sixty-one patients presented with PL, including four with SSI. However, PL was not directly suggested as a biomarker of SSI (p = 0.067). We revealed PL as a risk factor for SSI (p = 0.004, Odds ratio: 7.54). Among all cases, the lymphocyte count and CRP level differed significantly between the PL and non-PL groups at all perioperative time-points. The white blood cell count, neutrophil count, and CRP levels on postoperative day 7 significantly differed between the SSI and non-SSI cases in the PL group. The area under the curve (AUC) for CRP was greater than that of the other parameters. The neutrophil count was only effective as a marker in the non-PL group. The combination of two cutoff values (CRP: 3.7 mg/dL (PL group) and neutrophil count: 6172/μL (non-PL group)) presented high specificity (87.2%) and sensitivity (88.9%), while only one cutoff value (CRP: 2.9 mg/dL) had a specificity of 77.4% and sensitivity of 77.8%.

CONCLUSIONS

Approximately one-fifth of patients developed PL post-surgery, which was a risk factor for SSI, with constant high inflammation. Grouping based on PL and establishing diagnostic cutoff values are more appropriate than establishing only one cutoff value for overall cases.

Establishment of a suitable combination of serological markers to diagnose surgical site infection following spine surgery: A novel surgical site infection scoring system

BACKGROUND

The accuracy rates of several effective serological markers of surgical site infection following spine surgery are unclear. We aimed to verify the accuracy of each significant marker and identify the most suitable and effective combination of these markers for the diagnosis of surgical site infection following spine surgery.

METHODS

This retrospective study enrolled 329 patients who underwent spine surgery for causes other than infectious spondylitis, including 9 patients with surgical site infection. Complete blood cell count, differential counts, and C-reactive protein levels were measured preoperatively and postoperatively (days 2 and 7). Serological data were compared among non-surgical site infection and surgical site infection cases. Cutoff values for items presenting significant differences were determined using receiver operating characteristic curves. Ratios in each serological factor at each time-point were compared. Combinations of these factors on postoperative day 7 and ratio items were investigated to determine the most suitable combination comprising the least number of items.

RESULTS

Significant differences were noted among four factors on postoperative day 7, except for the lymphocyte count. For the ratio items, significant differences were observed among 6 items. The combination of these ten markers was examined; each factor was assigned 1 point. The most suitable combination comprising 4 items, including neutrophil count, neutrophil-to-lymphocyte ratio, lymphocyte count ratio, and C-reactive protein ratio, presented an AUC of 0.95, with a cutoff value, sensitivity, and specificity of 3 points, 0.89, and 0.92, respectively.

CONCLUSION

The combination of four markers is the most suitable criterion for the surgical site infection scoring system following spine surgery, where scores of ≥3 points strongly indicate surgical site infection. This criterion may be a strong tool for detecting surgical site infection.

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Background

We aimed to determine the prevalence and risk factors of surgical site infection (SSI) after cesarean delivery (CD) in a rural area in China.

Methods

We identified 155 patients with incisional and organ/space SSIs by International Classification of Disease codes and matched them with 465 patients (controls) in a time-matched retrospective quality assurance analysis. Multiple logistic regression analyses were performed to examine the risk factors for SSI: the work-years of providers, the number of antenatal care (ANC) visits, CD after labor, positive discharge culture, postoperative C-reactive protein (CRP) levels and fever.

Results

and discussion: During the study, 155 women with SSI were identified among the 8640 patients who delivered by CD. The incidence of SSIs was 179 per 10 000patients (95%CI: 151–207 per 10 000 patients). The total duration of hospitalization in patients with SSI was 14.49 ± 8.68 days compared with 7.96 ± 2.35 days in patients with no SSI (P < 0.01). Multiple logistic regression analysis showed that the work-years of providers (odds ratio [OR] = 3.729, 95% confidence interval [CI]: 1.463–9.501, p = 0.006), irregular ANC visits (OR = 3.245, 95% CI: 1.264–8.329, p = 0.028), CD after labor (OR = 2.545, 95% CI: 0.935–6.926, p = 0.020), postoperative CRP level (OR = 2.545, 95% CI: 0.935–6.926, p = 0.016) and a positive discharge culture (OR = 2.954, 95% CI: 0.305–28.643, p = 0.019) were positively associated with SSI. However, the rates of maternal request (OR = 0.186, 95% CI: 0.065–0.535, p = 0.002) and postoperative fever (OR = 0.208, 95% CI: 0.087–0.494, p = 0.001) were negatively related to SSI.

Conclusions

Special attentions should be paid to CD patients who had irregular ANC visits, attempted labor, a positive discharge culture, higher CRP levels and fever after surgery, who had a greater risk of SSI.

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The incidence of SSIs was 179 per 10 000 patients (95%CI: 151–207).

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Risk factors of SSIs included: irregular ANC visits, a positive discharge culture.

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Higher CRP levels and fever after surgery had a greater risk of SSI.

Application of an index derived from the area under a neutrophil curve as a predictor of surgical site infection after spinal surgery

Background

Patients with prolonged and intense neutrophilia after spinal surgery are at high risk of developing surgical site infection (SSI). To date, there is no standard method for the objective assessment of the intensity and duration of neutrophilia. Thus, this retrospective observational study aimed to test a new index (I-index), developed by combining the duration and intensity of neutrophilia, as a predictor of SSI.

Methods

I-index was calculated based on the postoperative neutrophil percentage. A total of 17 patients with SSI were enrolled as cases, and 51 patients without SSI were selected as controls. The groups were matched at a ratio of 1:3 by age, sex, and surgery type. The differences in the I-index were compared between the groups. Moreover, we checked the cumulative I-index (c-I-index), which we defined as the area under the neutrophil curve from postoperative day 1 until the first clinical manifestation of SSI in each case. Furthermore, a cutoff for SSI was defined using the receiver operating characteristic curve.

Results

The median I-index-7, I-index-14, and c-I-index were significantly higher in the SSI group than those in the control group. For a cutoff point of 42.1 of the I-index-7, the sensitivity and specificity were 0.706 and 0.882, respectively. For a cutoff point of 45.95 of the I-index-14, the sensitivity and specificity were 0.824 and 0.804, respectively. For a cutoff point of 45.95 of the c-I-index, the sensitivity and specificity were 0.824 and 0.804, respectively.

Conclusion

We devised a new indicator of infection, i.e., the I-Index and c-I-index, and confirmed its usefulness in predicting SSI.

Changes in Invasiveness and Latent Infection Rate Associated with Switching the Approach in Total Hip Replacement

Purpose:

Muscle-sparing approaches for total hip replacement (THR) involve learning curves. This study aimed to clarify changes in invasiveness and infection rate with changes in approach.

Methods:

One surgeon changed the approach of THR from Dall’s approach (Dall) to anterolateral modified Watson-Jones approach (OCM). Another changed from Dall to a direct anterior approach (DAA). Another 3 surgeons changed from posterolateral approach (PL) to OCM. Subjects were 150 cases, comprising the last 25 cases with conventional approaches and the first 25 cases with new approaches (Dall to OCM: 25 + 25; Dall to DAA: 25 + 25; PL to OCM: 25 + 25 cases). Differences in operative time, bleeding volume, hospital stay, haemoglobin (Hb), white blood cell count, lymphocyte count, creatine kinase (CK) and C-reactive protein (CRP) were investigated.

Results:

In the change from Dall to OCM, only hospital stay decreased. In the change from Dall to DAA, hospital stay and CRP decreased, but bleeding volume increased. In the change from PL to OCM, operative time, CRP and CK decreased, but Hb also decreased. Cases with lymphocyte count <1000/μL or lymphocytes comprising <10% of total white blood cells at around day 4 after surgery were defined as latent infection cases. In these cases, operative time was longer, Hb was lower and CK was higher.

Conclusion:

Introducing muscle-sparing approaches improved many markers of invasiveness, but some items deteriorated. In the early stages of introducing a new approach, choosing cases without obesity and without high muscle volume may reduce the risk of infection.

Interleukin-6 as inflammatory marker of surgical site infection following spinal surgery

BACKGROUND

In order to elucidate whether serum inflammatory markers identify patients with local surgical site infection(SSI) as underlying disease for recurrent or new symptomatology following spine surgery, we evaluated the diagnostic potential of interleukin-6(IL-6) as a marker of SSI. The diagnostic significance of IL-6 was compared to the standard serum inflammatory markers C-reactive protein(CRP) and white blood cell count (WBCC).

METHOD

Ninety-eight consecutive patients with readmission due to recurrent or new symptomology after spinal surgery of degenerative spine disorders entered the study. Baseline patients' characteristics and the abovementioned inflammatory markers were collected, and arithmetical means with standard deviation, area under the curve (AUC), thresholds, sensitivity, specificity, positive(+)likelihood ratio (LR), and negative(-)LR with corresponding 95% confidence interval(95%CI) were calculated and correlated with presence or absence of SSI.

RESULTS

Nine patients suffered from a SSI, whereas the remaining 89 patients had a recurrent/adjacent-segment degenerative disorder without evidence of infection. The most significant parameter for diagnosing a SSI was serum IL-6 (cut-off value > 15.3 pg/ml, AUC = 0.954, SE = 85.7%, SP = 97.3%), followed by CRP (cut-off value = 0.8 mg/dl, AUC = 0.916, SE = 88.9%, SP = 84.5%) CONCLUSIONS: In the case of recurrent or new symptomatology following spinal surgery, serum IL-6 has the highest diagnostic potential for diagnosing spinal SSI.

Surgical Site Infection, Readmission, and Reoperation After Posterior Long Segment Fusion

STUDY DESIGN

Retrospective case series.

OBJECTIVE

We sought to identify risk factors associated with surgical site infection (SSI) after posterior long segment spinal fusion (PLSF).

SUMMARY OF BACKGROUND DATA

Patients who undergo PLSF may be at elevated risk of SSI. Identifying factors associated with SSI in these operations can help risk stratify patients and tailor management.

METHODS

We analyzed PLSFs-seven or more levels-at our institution from 2000 to 2015. Data on patients' clinical characteristics, procedural factors, and antimicrobial management were collected. Multivariable analysis identified factors independently associated with outcomes of interest.

RESULTS

In 628 cases, SSI was associated with steroid use (P = 0.024, odds ratio [OR] = 2.54) and using cefazolin (P < 0.001, OR = 4.37) or bacitracin (P = 0.010, OR 3.49) irrigation, as opposed to gentamicin or other irrigation. Gram-positive infections were more likely with staged procedures (P = 0.021, OR 4.91) and bacitracin irrigation (P < 0.001, OR = 17.98), and less likely with vancomycin powder (P = 0.050, OR 0.20). Gram-negative infections were more likely with a history of peripheral arterial disease (P = 0.034, OR = 3.21) or cefazolin irrigation (P < 0.001, OR 25.47). Readmission was more likely after staged procedures (P = 0.003, OR = 3.31), cervical spine surgery (P = 0.023, OR = 2.28), or cefazolin irrigation (P = 0.039, OR = 1.85). Reoperation was more common with more comorbidities (P = 0.022, OR 1.09), staged procedures (P < 0.001, OR = 4.72), cervical surgeries (P = 0.013, OR = 2.36), more participants in the surgery (P = 0.011, OR = 1.06), using cefazolin (P < 0.001, OR = 3.12) or bacitracin (P = 0.009, OR = 3.15) irrigation, and higher erythrocyte sedimentation rate at readmission (P = 0.009, OR = 1.04). Washouts were more likely among patients with more comorbidities (P = 0.013, OR = 1.16), or who used steroids (P = 0.022, OR = 2.92), and less likely after cervical surgery (P = 0.028, OR = 0.24). Instrumentation removal was more common with bacitracin irrigation (p = 0.013, OR = 31.76).

CONCLUSION

Patient factors, whether a procedure is staged, and choice of antibiotic irrigation affect the risk of SSI and ensuing management required.Level of Evidence: 4.

Postoperative lymphocyte percentage and neutrophil-lymphocyte ratio are useful markers for the early prediction of surgical site infection in spinal decompression surgery

PURPOSE

Although the neutrophil-lymphocyte ratio (NLR) is a simple biomarker for inflammation, its diagnostic value for predicting surgical site infection (SSI) after spinal decompression surgery has not been extensively investigated. We aimed to determine the predictive value of NLR for SSI in patients undergoing spinal decompression surgery.

METHODS

We performed a retrospective observational study of patients who underwent spinal decompression surgery. Consecutive 254 patients were divided into an SSI group and a non-SSI group based on the presence of SSI. We evaluated which markers, including NLR, differed significantly between groups. We then determined the diagnostic cutoff values of these markers for the prediction of SSI based on the significance in the univariate analysis.

RESULTS

The incidence of SSI was 7 of 254 patients (2.8%). Univariate analysis showed that there were significant differences in the C-reactive protein (CRP) level at 1 day postoperatively; neutrophil and lymphocyte percentage and NLR at 3-4 days postoperatively; and CRP level, white blood cell count, neutrophil count and percentage, lymphocyte percentage, and NLR at 6-7 days postoperatively between SSI and non-SSI groups. Among these markers, the cutoff values of lymphocyte percentage and NLR at 3-4 days postoperatively for the prediction of SSI were ≤15.1% and ≥4.91, respectively. The cutoff values of lymphocyte percentage and NLR at 6-7 days postoperatively were ≤19.8% and ≥3.21, respectively.

CONCLUSIONS

Lymphocyte percentage and NLR at 3-4 and 6-7 days postoperatively were useful markers for the early prediction of SSI in patients who had undergone spinal decompression surgery. These parameters may aid in identifying patients at higher risk of SSI after spinal decompression surgery.

Usefulness of inflammatory markers and clinical manifestation for an earlier method to diagnosis surgical site infection after spinal surgery

PURPOSE

To put forward a method for earlier diagnosis of surgical site infection (SSI) after spinal surgery and identify the best cut-offs of the selective signs.

METHODS

Ninety cases were prospectively collected in consecutive patients who underwent spinal surgery. The patients were divided into the SSI group and the normal group. White blood cell (WBC) count, lymphocyte count, serum amyloid A (SAA), procalcitonin (PCT) and C-reactive protein (CRP) were collected pre-operatively and at three andsix days post-operatively. Erythrocyte sedimentation rates (ESR) were acquired pre-operatively and at six days post-operatively. Body temperature (BT) was measured every day during hospitalisation. The conditions of the surgical sites were recorded at three and six days post-operatively. Differences of BT, the conditions of the wound and the values of the inflammatory markers between the two groups were studied. Finally, we used the receiver operating characteristic curve (ROC curve) to determine the best cut-offs of the selected signs.

RESULTS

Of the 90 patients, SSI occurred in seven and five of them reached a definite diagnosis of SSI as their bacterial cultures were positive. Significant differences were found in CRP levels at three and six days post-operatively with a cut-off of > 59.4 mg/L and > 34.9 mg/L, respectively; ESR level at six days post-operatively with a cut-off of > 51.5 mm/h; PCT at three days post-operatively with a cut-off of > 0.11 ng/mL; and BT at three days post-operatively with a cut-off of > 37 °C. Also, examination of the wound is also an important sign of SSI.

CONCLUSION

CRP, ESR and PCT are considered useful markers for earlier diagnosis of SSI. Combining the above markers with BT and the wound condition yields more accurate results.

Increased interleukin-6 and C-reactive protein levels after instrumented lumbar spine fusion in older patients

PURPOSE

Interleukin 6 (IL-6) and the acute phase C-reactive protein (CRP) blood concentrations after lumbar spine fusion may be affected by age. The purpose of this prospective observational study was to assess postoperative serum levels of pro-inflammatory IL-6 and CRP after instrumented lumbar spine fusion surgery. We hypothesized that older patients would have increased levels of IL-6 and CRP after surgery.

METHODS

IL-6 and high-sensitive CRP biochemical marker levels were measured before instrumented spinal fusion, and postoperatively at 1 and 3 days, 6 weeks, and 3 months. The 49 patients in this sample were divided into two groups: age ≤ 60 years ( n = 23) and age > 60 years ( n = 26).

RESULTS

Acute changes in IL-6 high-sensitivity and CRP from preoperative levels to postoperative day (POD) 1 increased with age. Mean (95% CI) difference between the age-groups in changes of IL-6 at PODs 1 and 3 was 45 pg/ml (10-83, p = 0.014) and 20 pg/ml (5-36, p = 0.021), respectively. Mean (95% CI) difference between groups in changes of CRP at PODs 1 and 3 was 9.6 mg/l (-3.5 to 22.7, p = 0.47) and 24.8 mg/l (-17 to 67, p = 0.33), respectively. Both groups had decreased IL-6 and CRP levels at 6 weeks after surgery compared to the preoperative level.

CONCLUSIONS

Elevation of IL-6 and CRP is stronger in patients over 60 years old after instrumented lumbar spinal fusion. The CRP and IL-6 are sensitive markers for acute postoperative inflammation. Even high acute CRP values do not necessarily indicate postoperative infection.

Comparison of Preliminary clinical outcomes between percutaneous endoscopic and minimally invasive transforaminal lumbar interbody fusion for lumbar degenerative diseases in a tertiary hospital: Is percutaneous endoscopic procedure superior to MIS-TLIF? A prospective cohort study

BACKGROUND

Percutaneous endoscopic transforaminal lumbar interbody fusion (PETLIF) has been used in the treatment of lumbar degenerative diseases, as a novel minimally invasive technique.

OBJECTIVES

To compare the surgical trauma and the medium-short term postoperative outcomes of PETLIF and traditional minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF).

METHODS

From April to August of 2018, 75 patients with lumbar degenerative diseases received PETLIF (Group PE, 35 cases) or MIS-TLIF (Group MIS, 40 cases) were enrolled in the prospective cohort study. We recorded the serum creatine kinase (CK) and C-reactive protein (CRP), blood loss, visual analog scale (VAS), Oswestry Disability Index (ODI), modified Macnab criteria score, complications, and fusion rates of the 2 groups.

RESULTS

There were significant reductions in CRP (P = 0.002) on postoperative day (POD) 3, and CK (P = 0.011) on POD 1 for Group PE than Group MIS. The mean true total blood loss (P < 0.001), intraoperative blood loss (P < 0.001), postoperative drains (P < 0.001), and hidden blood (P = 0.020) in the Group PE were significantly less compared with Group MIS. The VAS score for low-back pain, leg pain and ODI score improved significantly in both groups after surgery (P < 0.05). The VAS of low-back pain on POD 1 was significant less (P < 0.001) for Group PE. There was no statistical difference (P = 0.561) in CT fusion rates between Group PE (85%) and Group MIS (92%). No serious complication was observed in any patients.

CONCLUSION

The study indicated that PETLIF had advantages of less surgical trauma, less postoperative low-back pain, less hidden blood loss, and faster recovery, compared with MIS-TLIF. There was no significant difference in medium-short term surgical outcomes between the 2 techniques. However, the indications of PETLIF is relatively limited, and the learning curve of PETLIF is deep, surgeons need to select indications strictly. Further study with big sample size and long-term follow-up is needed.

Procalcitonin and Neutrophil Lymphocyte Ratio After Spinal Instrumentation Surgery

STUDY DESIGN

This was a retrospective observational study.

OBJECTIVE

To assess the diagnostic value of procalcitonin (PCT) and neutrophil lymphocyte ratio (NLR) for predicting surgical site infection (SSI) in patients undergoing spinal instrumentation surgery, we analyzed a large consecutive cohort of patients who had undergone spinal instrumentation surgery.

SUMMARY OF BACKGROUND DATA

Although PCT and NLR are commonly used as markers for bacterial infection, the diagnostic value of these factors for predicting SSI in the context of spinal instrumentation surgery has not been extensively investigated.

METHODS

We retrospectively investigated 242 patients who underwent spinal instrumentation surgery and evaluated the significance of various postoperative measures for predicting SSI, including PCT and NLR. We then determined the diagnostic cut-off values for these markers in the prediction of SSI using receiver operating characteristic curve analysis.

RESULTS

Among the 242 patients analyzed, 10 were diagnosed with infection. Even though univariate analysis showed that neutrophil percentage and NLR at 6 to 7 days postoperatively were significant predictors for SSI, PCT at 6 to 7 days postoperatively did not differ significantly between the SSI and non-SSI groups. The cut-off value used for neutrophil percentage at 6 to 7 days postoperatively was more than 69.0% [sensitivity, 80.0%; specificity, 70.0%; area under the curve, 0.737]. The cut-off value used for NLR at 6 to 7 days postoperatively was 3.87 (sensitivity, 70.0%; specificity, 73.2%; area under the curve, 0.688).

CONCLUSION

Neutrophil percentage and NLR at 6 to 7 days postoperatively were more useful markers than PCT at 6 to 7 days postoperatively for early prediction of SSI in patients who had undergone spinal instrumentation surgery. Therefore, routine use of PCT as a predictor of postoperative infection is not supported by the results of this study.

LEVEL OF EVIDENCE

4.

Retrospective study to evaluate the clinical significance of a second rise in C-reactive protein level following instrumented spinal fusion surgery

BACKGROUND

This study aimed to identify the incidence and causes of a second rise in C-reactive protein (CRP) levels following spinal instrumentation surgery and to help determine how an abnormal CRP response should be interpreted and managed during postoperative care.

METHODS

The medical records of 948 patients who underwent instrumented spine fusion surgery and met the inclusion criteria were retrospectively reviewed to assess the frequency and causes of a second rise (SR) of CRP. A SR of CRP was defined when the CRP level after postoperative day 7 increased by more than 0.5 mg/dl from that at the previous time-point. The diagnostic cut-off value of CRP elevation for detection of surgical site infection (SSI) was determined. Cut-off values were analyzed using receiver operating characteristic (ROC) curves. Bayes' theorem was used to determine blood test posterior probabilities for SSI-positive cases using cutoff values of re-evaluated CRP levels.

RESULTS

SR of CRP occurred in 107 of the 948 patients. Of the patients with SR of CRP, 38 (35%) patients had developed SSI, 33 (31%) patients had causes other than SSI, and the remaining 36 patients had unidentified causes. Among the patients with SR, excluding those with causes other than SSI, the best diagnostic cut-off value of SR for detection of SSI was 3.04 mg/dl (area under the curve was 0.74). The posterior test probability was 84.4%.

CONCLUSIONS

For patients with SR of CRP, who had no causes other than SSI, an SR value of 3.04 mg/dl correlated with a high probability of developing SSI.

Predictive value of post-operative neutrophil/lymphocyte count ratio for surgical site infection in patients following posterior lumbar spinal surgery

OBJECTIVE

Surgical site infection (SSI) is a common complication in patients following posterior lumbar spinal surgery. Various laboratory data such as laboratory parameters derived neutrophil/lymphocyte count ratio (NLR), have been applied for the prediction of SSI, but more studies are necessary to evaluate the significance of these indicators. Here, our study aims to investigate the predictive value of total white blood cells (WBCs), count and percentages of neutrophils and leukocytes, NLR, and C-reactive protein (CRP) for surgical site infection (SSI) in patients after posterior lumbar spinal surgery.

METHODS

A total of 293 patients who underwent posterior lumbar spinal surgery were enrolled in this study. Each patient's medical history was retrospectively reviewed, and patients were divided into the deep SSI group (n = 13) and the non-SSI group (n = 280). Laboratory data including total WBC, count and percentages of neutrophils and leukocytes, NLR at 1 week before the operation and the 4 and 7 days post-operation, and CRP at 4 and 7 days post-operation were analysed between the SSI and non-SSI groups. Moreover, predictive power and cut-off of NLR for SSI were determined by receiver operating characteristic curve (ROC) results.

RESULTS

Data revealed that the medians of NLR were markedly increased in the SSI group as compared to that in non-SSI group at 4 days (p = 0.011) and 7 days (p = 0.047) post-operation. Moreover, the neutrophil percentage was also dramatically increased in the SSI group at both 4 and 7 days post-operation (p = 0.010 and p = 0.030) respectively compared to the non-SSI group. However, no significant difference was observed between the groups 1 week before the operation. ROC results showed that NLR at 4 days (cut-off >5.19; sensitivity: 61.5%; specificity: 77.6%; AUC = 0.708) and 7 days (cut-off >3.85; sensitivity: 69.2%; specificity: 62.7%; AUC = 0.663) post-operation could significantly discriminate the SSI and non-SSI groups. Logistic regression analysis showed that NLR at both post-operative time points (OR = 1.218; p = 0.003 and OR = 1.296; p = 0.048) could be valuable predictors for SSI.

CONCLUSION

NLR at 4 and 7 days post-operation are valuable laboratory predictors for SSI in patients with posterior lumbar spinal surgery.

Postoperative lymphopenia: An independent risk factor for postoperative pneumonia after lung cancer surgery, results of a case-control study

Objective

Postoperative lymphopenia has been proposed as a risk factor for postoperative infections but has never been identified as such in a multivariate analysis. Postoperative pneumonia (POP) is one of the most common complications after lung cancer surgery and is associated with a worse outcome. We aimed to evaluate the association between postoperative lymphopenia and POP after lung cancer surgery.

Methods

Patients admitted for lung cancer surgery (lobectomy, bilobectomy, or pneumonectomy) aged ≥ 18 years and with no history of an immunosuppressive state were eligible for inclusion. Lymphocyte counts were determined in blood drawn on the day before surgery and at postoperative days 1, 3 and 7. POP diagnosis was based on clinical, biological and radiological data. A logistic regression model adjusted on currently described risk factors for POP was used to explain the onset of this condition.

Results

Two hundred patients were included, of whom 43 (21.5%) developed POP. Preoperative lymphocyte count was 1.8±0.6x10⁹ cells/L and 2.0±0.7x10⁹ cells/L in patients with and without POP, respectively (P = .091). In both groups, the lymphocyte count nadir occurred at postoperative day 1. In multivariate analysis, lymphopenia at postoperative day 1 was significantly associated with increased risk of POP (odds ratio: 2.63, 95% CI [1.03–5.40]). POP rate at postoperative day 7 was higher in patients presenting low lymphocyte counts (≤1.19x10⁹ cells/L) at postoperative day 1 (P = .003).

Conclusions

Our study showed that lymphopenia following lung cancer surgery was maximal at postoperative day 1 and was associated with POP.

Lymphocyte Count at 4 Days Postoperatively: A Reliable Screening Marker for Surgical Site Infection After Posterior Lumbar Decompression Surgery

STUDY DESIGN

Case-control study.

OBJECTIVE

To identify laboratory markers for surgical site infection (SSI) in posterior lumbar decompression surgery, which are not affected by operative factors, and to determine the diagnostic cutoffs of these markers.

SUMMARY OF BACKGROUND DATA

Numerous laboratory markers are used for the early detection of SSI; however, these markers may be affected by operative factors.

METHODS

The study included 182 participants. They were divided into an SSI group (patients who developed deep SSI; n = 8) and a no-SSI group (n = 174). We reviewed data on the C-reactive protein level and total white blood cell count and differential count before posterior lumbar decompression surgery and 1 and 4 days postoperatively. We determined which markers differed significantly between the groups and identified the markers that were not affected by operative factors (operative time, intraoperative blood loss, and number of operative segments) in the no-SSI group. We then determined the diagnostic cutoffs of these unaffected markers using receiver operating characteristic curves.

RESULTS

We identified the lymphocyte percentage at 4 days postoperatively (cutoff, <19.4%; sensitivity, 80.0%; specificity, 62.5%; area under the curve, 0.78) and lymphocyte count at 4 days postoperatively (cutoff, <1010/μL; sensitivity, 93.7%; specificity, 62.5%; area under the curve, 0.78) as reliable markers.

CONCLUSION

Lymphocyte percentage and count at 4 days postoperatively are reliable markers for SSI after posterior lumbar decompression surgery. Lymphocyte count at 4 days postoperatively can be considered as a superior marker for screening because it has a high sensitivity and can be measured early.

LEVEL OF EVIDENCE

4.

Comparison of neutrophil and lymphocyte at 1 and 4 days postoperatively: reliable and early detection markers for surgical site infection following instrumented spinal fusion

Introduction

To identify the temporal comparison of biochemical markers for early detection of surgical site infection (SSI) following instrumented spinal fusion that are not affected by operative factors.

Methods

We reviewed data on C-reactive protein level and total white blood cell count and differential count before instrumented spinal fusion and at 1, 4, and 7 days postoperatively. The 141 patients in our sample were divided into an SSI group (patients who developed deep SSI) and a non-SSI group. We investigated the peak or nadir value day and identified those not affected by operative circumstances (operating time, intraoperative blood loss, and number of fusion segments) in the non-SSI group. If there was a significant difference between the peak or nadir value day and the next survey day, we considered the temporal comparison between these unaffected markers as an indicator of SSI and examined the usefulness of these indicators by calculating sensitivity and specificity. Furthermore, we investigated the usefulness of the combination of these markers (if even each one marker was recognized, we considered it positive).

Results

Four biochemical markers of SSI were selected: neutrophil percentage at postoperative day 4 more than day 1 (sensitivity 36%, specificity 95%), neutrophil count at postoperative day 4 more than day 1 (sensitivity 46%, specificity 93%), lymphocyte percentage at postoperative day 4 less than day 1 (sensitivity 36%, specificity 90%), and lymphocyte count at postoperative day 4 less than day 1 (sensitivity 36%, specificity 90%). The combination of these markers showed sensitivity 100%, specificity 80%, respectively.

Conclusions

Four markers are reliable indicators for early detection of SSI following spinal instrumented fusion because they are not affected by operative factor. The combination of each indicator had both high sensitivity and specificity. Therefore, it is reliable and much useful for early detection of SSI.