What are the risk factors for surgical site infection after spinal fusion? A meta-analysis

Readmission rate after adult scoliosis surgery on primary cases over 45 years-old with long term follow-up

PURPOSE

Scoliosis surgery is becoming increasingly frequent. Rate of readmission is little discussed in the literature. It is an interesting data for the patient's information and for public authorities to calculate cost-effectiveness. Aim of the study was to evaluate rate and causes of short and long-term readmissions in patients > 45 years old operated on for a scoliosis primary cases, then to look for predictors of these readmissions.

METHODS

In this monocentric retrospective cohort study, over 45 years-old scoliosis primary cases operated on between 2015 and 2018 and with a minimum of 2 years follow-up were included. The number of readmissions and their causes were analyzed. Rehospitalized patients (RH) were then compared to non-rehospitalized patients (NRH). Risk factors were sought using a multivariate analysis by logistic regression.

RESULTS

105 patients were included (90% female; 64 ± 8 years). 56% were readmitted at least once. Main cause of readmission as pseudarthrosis (70%). Among the RH patients, fifty-eight required at least one revision. We found no significant difference between RH and NRH, apart from the rate of immediate post-operative medical complications which was significantly higher in RH (17% (n = 11) vs. 4% (n = 2), p = 0.04). According to multivariate analysis, BMI and age were found as predictors of readmission of mechanical origin, and BMI for readmissions of septic origin.

CONCLUSION

The readmission rate after scoliosis surgery was 56%. The main cause was pseudarthrosis. Rehospitalized patients had more immediate post-operative medical complications. The elderly and overweight patients are more likely to be readmitted for mechanical or septic reasons.

Comparison of Surgical Site Infection After Instrumented Spine Surgery in Patients With High Risk of Infection According to Different Antibiotic Prophylaxis Protocols: A Cohort Study of 132 Patients With a Minimum Follow-Up of 1 year

STUDY DESIGN

Observational Study.

OBJECTIVES

Surgical site infections (SSIs) are one of the major complications in spine surgery. Numerous factors that increase the risk of SSI have been widely described. However, clinical guidelines on antibiotic prophylaxis are usually common for all patients. There are no specific guidelines for patients with a high risk of infection. The aim of this paper is to create a specific protocol for patients at high risk of SSI.

METHODS

This is a three-cohort study using a prospective database. Risk patients are those who meet at least two of the following criteria: obesity, diabetes, reoperation and immunosuppression. Between October 2021 and April 2023, 132 patients were recruited.They were divided into three cohorts: cohort A, 46 patients, standard prophylaxis with cefazolin 2 g/8 h for 24 h; cohort B, 46 patients, cefazolin 2 g/8h and amikacin 500 mg/12 h for 24 h; cohort C, 40 patients, cefazolin 2 g/8h and amikacin 500 mg/12 h for 72 h.

RESULTS

There was a significant decrease in the infection rate depending on the prophylaxis (23.9% in cohort A, 8.7% in cohort B, and 2.5% in cohort C). When logistic regression models were applied and cohorts B and C were compared with A, the following results were obtained: OR of 0.30 (CI: 0.08 - 0.97; P = 0.057) and 0.08 (IC: 0.00 - 0.45; P = 0.019), respectively.

CONCLUSIONS

Prophylaxis with prolonged double antibiotic therapy with cefazolin and amikacin is associated with a statistically significant decrease in the rate of SSI in patients with a high risk of infection.

Surgical and procedural antibiotic prophylaxis in the surgical ICU: an American Association for the Surgery of Trauma Critical Care Committee clinical consensus document

The use of prophylactic measures, including perioperative antibiotics, for the prevention of surgical site infections is a standard of care across surgical specialties. Unfortunately, the routine guidelines used for routine procedures do not always account for many of the factors encountered with urgent/emergent operations and critically ill or high-risk patients. This clinical consensus document created by the American Association for the Surgery of Trauma Critical Care Committee is one of a three-part series and reviews surgical and procedural antibiotic prophylaxis in the surgical intensive care unit. The purpose of this clinical consensus document is to provide practical recommendations, based on expert opinion, to assist intensive care providers with decision-making for surgical prophylaxis. We specifically evaluate the current state of periprocedural antibiotic management of external ventricular drains, orthopedic operations (closed and open fractures, silver dressings, local, antimicrobial adjuncts, spine surgery, subfascial drains), abdominal operations (bowel injury and open abdomen), and bedside procedures (thoracostomy tube, gastrostomy tube, tracheostomy).

Reduction of Instrumentation-Related Spine Surgical Site Infections After Optimization of Surgical Techniques. A Single Center Retrospective Analysis

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

Although surgical risk factors for developing spine surgical site infections (S-SSI) have been identified, the impact of such knowledge in its prevention has not been demonstrated.

METHODS

We evaluated in 500 patients undergoing spine surgery between 2011 and 2019 at Hospital 12 de Octubre the changes in S-SSI rates over time. Surgical variables independently related to S-SSI were analyzed by univariate and multivariate analysis using binary logistic regression models. A case-control sub-analysis (1:4), matched by the surgical variables identified in the overall cohort was also performed.

RESULTS

Twenty cases of S-SSI were identified (4%), with a significant decrease in the incidence rate across consecutive time periods (6.6% [2011-2014] vs .86% [2015-2019]; P-value <.0001)). Multivariate analysis identified arthrodesis involving sacral levels (odds ratio [OR]: 2.57; 95% confidence interval [95%CI]: 1.02-6.47; P-value = .044) and instrumentation over 4-8 vertebrae (OR: 2.82; 95%CI: 1.1-7.1; P-value = .027) as independent risk factors for S-SSI. The reduction in the incidence of S-SSI concurred temporally with a reduction in instrumentations involving 4-8 vertebrae (55% vs 21.8%; P-value <.0001) and sacral vertebrae (46.9% vs 24.6%; P-value <.0001) across both periods. The case-control analysis matched by these surgical variables failed to identify other factors independently related to the occurrence of S-SSI.

CONCLUSIONS

Spinal fusion of more than 4 levels and the inclusion of sacral levels were independently related to the risk of S-SSI. Optimization of surgical techniques by reducing these two types of instrumentation could significantly reduce S-SSI rates.

Investigating the efficacy of vacuum sealing drainage versus traditional negative pressure drainage in treating deep incision infections following posterior cervical internal fixation-a retrospective cohort study

BACKGROUND

Assessing the efficacy and safety of Vacuum Sealing Drainage (VSD) in treating deep incision infections (DII) following posterior cervical internal fixation.

METHODS

We retrospectively studied the clinical effects of VSD and Traditional Negative Pressure Drainage (TND) on 12 patients with deep incision infection after posterior cervical fixation surgery who were treated in our department from 2012 to 2020. A comparison of patient-related factors (age, gender, BMI, comorbidities, initial internal fixation surgery segment, preoperative laboratory inflammation indicators) and surgical-related factors (postoperative duration of fever, positive rate of drainage fluid bacterial culture, Visual Analogue Scale (VAS) score at 3 days after surgery, laboratory indicators at 3 days after surgery, debridement frequency and drainage time, hospital stay, internal fixation retention rate, and infection recurrence rate) between the VSD group and the TND group was conducted using independent sample t tests to draw experimental conclusions.

RESULTS

This study included 12 patients, with six cases of VSD (5 males and 1 female) and six cases of TND (4 males and 2 females). The VSD group had significantly lower postoperative fever time (1.50 ± 0.46 days vs. 4.28 ± 0.97 days, P < 0.05), a higher positive rate of bacterial cultures in drainage fluid (5/6 vs. 2/6, P < 0.05), lower 3 day VAS scores (3.13 ± 0.83 vs. 3.44 ± 0.88, P < 0.05), lower 3 day CRP levels (66.89 ± 23.65 mg/L vs. 57.11 ± 18.18 mg/L, P < 0.05), a shorter total drainage time (14.50 ± 2.98 days vs. 22.56 ± 3.01 days, P < 0.05), and a higher total drainage flow rate (395.63 ± 60.97 ml vs. 155.56 ± 32.54 ml, P < 0.05) than the TND group (the total drainage volume throughout the entire treatment process). In addition, the frequency of debridement (2.67 ± 0.52 times vs. 3.17 ± 0.41 times, P < 0.05) and average hospital stay (23.13 ± 3.27 days vs. 34.33 ± 6.86 days, P < 0.05) were significantly lower in the VSD group, although both groups retained internal fixation.

CONCLUSIONS

VSD is a secure and effective treatment for deep incision infections that results from cervical posterior internal fixation surgery.

Association between malnutrition and surgical site wound infection among spinal surgery patients: A meta-analysis

A surgical site infection (SSI) is one of the most common complications of spinal surgery. Malnutrition has also been linked to SSI after other surgical procedures. However, whether malnutrition is a risk factor for SSI after spinal surgery remains controversial. Therefore, we performed a meta-analysis to comprehensively evaluate the relationship between malnutrition and SSI. Relevant studies of the correlation between malnutrition and SSI were retrieved from the Cochrane Library, EMBASE, PubMed, Web of Science, China National Knowledge Infrastructure and Wanfang Data from database inception to 21 May 2023. Two reviewers independently assessed the included studies, and a meta-analysis was performed using STATA 17.0 software. A total of 24 articles with 179 388 patients were included: 3919 and 175 469 cases comprised the SSI and control groups, respectively. The meta-analysis results showed that malnutrition significantly increased the SSI incidence (odds ratio, 1.811; 95% confidence interval, 1.512-2.111; p < 0.001). These results suggest that patients with malnutrition are at higher risk for SSI after surgery. However, because of significant differences in sample sizes among studies, and because some studies had limitations to their methodological quality, further validation of these results by additional high-quality studies with larger sample sizes is necessary.

Effects of Preoperative Use of Povidone-Iodine-Impregnated Dressing on Postoperative Rate of Surgical Site Infection in Patients Undergoing Posterolateral Lumbar Spinal Fusion Surgery: A Randomized, Nonblinded, Active-Controlled Trial

BACKGROUND AND OBJECTIVES

No study has evaluated the efficacy of using preoperative antiseptic dressings in reducing the rate of surgical site infection (SSI) in spine surgery thus far. To investigate the efficacy of the use of preoperative povidone-iodine-impregnated antiseptic dressings in patients undergoing instrumented posterolateral lumbar spinal fusion.

METHODS

This was a randomized, nonblinded, active-controlled, parallel-group clinical trial. Patients were randomly assigned to the 2 study groups, including treatment and control. Patients in the treatment group received povidone-iodine-impregnated antiseptic dressing applied to the anticipated incision site 12 hours before the operation. The control group merely received the standard perioperative care with no additional intervention or placebo. Patients were followed up for 90 days, and SSIs were recorded.

RESULTS

A total of 200 patients were included in this study (100 in each arm). Three cases of SSI were observed in the treatment group compared with 12 in the control one. A significant reduction in the postoperative rate of SSI was observed in the treatment group compared with the control one (P = .029). In addition to study intervention (P = .029), body mass index (P = .005), smoking status (P = .005), duration of the procedure (P = .003), American Society of Anesthesiologists class (P = .002), and diabetes mellitus (P < .001) were significantly associated with the postoperative rate of SSI.

CONCLUSION

To the best of our knowledge, this study for the first time showed that preoperative use of antiseptic dressings is significantly effective in reducing the rate of SSI in instrumented posterior lumbar spinal fusion surgery. Future studies are warranted to evaluate the efficacy of different preparations or the effectiveness of the present one in patients undergoing spine procedures with other surgical characteristics.

Does surgical site infection affect patient-reported outcomes after spinal surgery? A multicenter cohort study

BACKGROUND

Surgical site infections are common in spinal surgeries. It is uncertain whether outcomes in spine surgery patients with vs. without surgical site infection are equivalent. Therefore, we assessed the effects of surgical site infection on postoperative patient-reported outcomes.

METHODS

We enrolled patients who underwent elective spine surgery at 12 hospitals between April 2017 and February 2020. We collected data regarding the patients' backgrounds, operative factors, and incidence of surgical site infection. Data for patient-reported outcomes, namely numerical rating scale, Neck Disability Index/Oswestry Disability Index, EuroQol Five-Dimensional questionnaire, and 12-Item Short-Form Health Survey scores, were obtained preoperatively and 1 year postoperatively. We divided the patients into with and without surgical site infection groups. Multivariate logistic regression analyses were performed to identify the risk factors for surgical site infection. Using propensity score matching, we obtained matched surgical site infection-negative and -positive groups. Student's t-test was used for comparisons of continuous variables, and Pearson's chi-square test was used to compare categorical variables between the two matched groups and two unmatched groups.

RESULTS

We enrolled 8861 patients in this study; 74 (0.8 %) developed surgical site infections. Cervical spine surgery and American Society of Anesthesiologists physical status classification ≥3 were identified as risk factors; microendoscopy was identified as a protective factor. Using propensity score matching, we compared surgical site infection-positive and -negative groups (74 in each group). No significant difference was found in postoperative pain or dysesthesia of the lower back, buttock, leg, and plantar area between the groups. When comparing preoperative with postoperative pain and dysesthesia, statistically significant improvement was observed for both variables in both groups (p < 0.01 for all variables). No significant differences were observed in postoperative outcomes between the matched surgical site infection-positive and -negative groups.

CONCLUSIONS

Patients with surgical site infections had comparable postoperative outcomes to those without surgical site infections.

Effects of different sponge implantation methods of negative pressure wound therapy on wound healing of deep surgical site infection after spinal surgery

PURPOSE

After spinal surgery, negative pressure wound treatment (NPWT) improves deep surgical site infection (DSSI) wound healing. This research compared the healing benefits of two sponge implantation strategies in NPWT for DSSI.

METHODS

21 patients with DSSI utilized NPWT to improve wound healing following spine surgery were followed from January 1, 2012 to December 31, 2021. After antibiotic treatment failure, all these patients with DSSI received extensive debridement and NPWT. They are grouped by sponge placement method: centripetal reduction and segment reduction. The two groups' hospital stays, NPWT replacement frequency, wound healing time, healing speed, and quality of wound healing (POSAS score) were compared.

RESULTS

All patients had been cured by the end of December 2022, and the mean follow-up time was 57.48 ± 29.6 months. Surgical incision length did not vary across groups (15.75±7.61 vs. 15.46±7.38 cm, P = 0.747). The segmental reduction approach had shorter hospital stay and NPWT treatment times than the centripetal reduction method (39.25±16.04 vs. 77.38±37.24 days, P = 0.027). Although there is no statistically significant difference, the mean wound healing duration of segmental reduction group is faster than that of centripetal reduction group (0.82±0.39 vs 0.45±0.28 cm/d, P = 0.238), wound healing quality (POSAS) (33.54±8.63 vs 48.13±12.17, P = 0.408) is better in segmental reduction group, and NPWT replacement frequency (2.62 ± 1.04 vs 3.88 ± 1.25, P < .915) is smaller in segmental reduction group.

CONCLUSIONS

NPWT heals wounds and controls infection. Segmental reduction method accelerates wound healing, reduces hospital stay, and improves wound quality compared to central reduction method.

Risk Factors for Surgical Site Infection in Spinal Surgery and Interventions: A Retrospective Study

BACKGROUND

Surgical site infection following spinal surgery causes prolonged delay in recovery after surgery, increases cost, and sometimes leads to additional surgical procedures. We investigated risk factors for the occurrence of surgical site infection events in terms of patient-related, surgery-related, and postoperative factors.

METHODS

This retrospective study included 1000 patients who underwent spinal surgery in our hospital between April 2016 and March 2019.

RESULTS

Patient-related factors were dementia, length of preoperative hospital stay (≥ 14 days), and diagnosis at the time of surgery (traumatic injury or deformity). The one surgery-related factor was multilevel surgery (≥ 9 intervertebral levels), and the one postoperative factor was time to ambulation (≥ 7 days) were statistically significant risk factors for spinal surgical site infection.

CONCLUSION

One risk factor identified in this study that is amenable to intervention is time to ambulation. As delayed ambulation is a risk factor for postoperative surgical site infection, how medical staff can intervene in postoperative ambulation to further reduce the incidence of surgical site infection is a topic for future research.

Local contamination is a major cause of early deep wound infections following open posterior lumbosacral fusions

PURPOSE

Postoperative surgical site infection in patients treated with lumbosacral fusion has usually been thought to be caused by perioperative contamination. With the proximity of these incisions to the perineum, this study sought to determine if contamination by gastrointestinal and/or urogenital flora should be considered as a major cause of this complication.

METHODS

We conducted a retrospective review of adults treated with open posterior lumbosacral fusions between 2014 and 2021 to identify common factors in deep postoperative infection and the nature of the infecting organisms. Cases of tumor, primary infection and minimally invasive surgery were excluded.

RESULTS

489 eligible patients were identified, 20 of which required debridement deep to the fascia (4.1%). Mean age, operative time, estimated blood loss and levels fused were similar between both groups. The infected group had a significantly higher BMI. The mean time from primary procedure to debridement was 40.8 days. Four patients showed no growth, 3 showed Staphylococcus sp. infection (Perioperative Inside-Out) requiring debridement at 63.5 days. Thirteen showed infection with intestinal or urogenital pathogens (Postoperative Outside-In) requiring debridement at 20.0 days. Postoperative Outside-In infections led to debridement 80.3 days earlier than Perioperative Inside-Out infections (p = 0.007).

CONCLUSIONS

65% of deep infections in patients undergoing open lumbosacral fusion were due to early contamination by pathogens associated with the gastrointestinal and/or urogenital tracts. These required earlier debridement than Staphylococcus sp.

INFECTIONS

There should be renewed focus on keeping these pathogens away from the incision during the early stages of wound healing.

Association between immediate postoperative hypoalbuminemia and surgical site infection after posterior lumbar fusion surgery

PURPOSE

In this study, we intended to investigate the association between immediate postoperative hypoalbuminemia and surgical site infection (SSI), and determine a threshold value for postoperative hypoalbuminemia that can assist in risk stratification in patients after posterior lumbar fusion surgery.

METHODS

From January 2017 to December 2021, 466 consecutive patients who underwent posterior lumbar fusion surgery were selected to analyze the relationship between immediate postoperative hypoalbuminemia and SSI. Multivariate logistic regression analysis was performed to identify the independent risk factors of SSI and postoperative hypoalbuminemia. Receiver Operating Characteristic (ROC) analysis was used to determine the optimal value for postoperative hypoalbuminemia, and subsequent grouping was based on the identified threshold.

RESULTS

Of the total 466 patients, 25 patients (5.4%) developed SSI after surgery, and lower postoperative albumin (OR: 0.716, 95% CI: 0.611-0.840, p < 0.001) was independently associated with SSI. ROC analysis showed that the cutoff value of postoperative hypoalbuminemia was 32 g/L with a sensitivity of 0.760, specificity of 0.844, and a Youden index of 0.604. Postoperative SSI was more common in patients with postoperative hypoalbuminemia than in those without (21.6% vs. 1.6%, p < 0.001). Age, gender and operative duration were found to be independent predictors of postoperative hypoalbuminemia.

CONCLUSIONS

This study showed that immediate postoperative hypoalbuminemia was an independent risk factor for the development of SSI in patients who underwent posterior lumbar fusion. Even in patients with a normal preoperative serum albumin level, there was an increased risk of SSI when the postoperative albumin within 24 h was < 32 g/L.

Does Tobacco Smoking Affect the Postoperative Outcome of MIS Lumbar Decompression Surgery?

BACKGROUND

Tobacco smoking is a major cause of morbidity and mortality worldwide. Several authors reported a significant negative impact of smoking on the outcome of spinal surgeries. However, comparative studies on the effect of smoking on the outcome of minimally invasive (MIS) spinal decompression are rare with conflicting results. In this study, we aimed to evaluate clinical outcomes and postoperative complications following MIS decompression in current and former smoking patients compared to those of non-smoking patients.

METHODS

We used our prospectively collected database to retrospectively analyse the records of 188 consecutive patients treated with MIS lumbar decompression at our institution between November 2013 and July 2017. Patients were divided into groups of smokers (S), previous smokers (PS) and non-smokers (N). The S group and the PS group comprised 31 and 40 patients, respectively. The N group included 117 patients. The outcome measures included perioperative complications, revision surgery and length of stay. Patient-reported outcome measures included a visual analogue scale (VAS) for back pain and leg pain, as well as the Oswestry disability index (ODI) for evaluating functional outcomes.

RESULTS

Demographic variables, comorbidity and other preoperative variables were comparable between the three groups. A comparison of perioperative complications and revision surgery rates showed no significant difference between the groups. All groups showed significant improvement in their ODI and VAS scores at 12 and 24 months following surgery. As shown by a multivariate analysis, current smokers had lower chances of improvement, exceeding the minimal clinical important difference (MCID) in ODI and VAS for leg pain at 12 months but not 24 months postoperatively.

CONCLUSIONS

Our findings show that except for a possible delay in improvement in leg pain and disability, tobacco smoking has no substantial adverse impact on complications and revision rates following MIS spinal decompressions.

Surgical Site Infection After Primary Spinal Fusion Surgery for Adolescent Idiopathic Scoliosis: An Analysis of Risk Factors From a Nationwide Insurance Database

STUDY DESIGN

Retrospective review.

OBJECTIVE

The purpose of this study was to quantify the incidence and factors associated with surgical site infection (SSI) in pediatric patients undergoing spinal fusion for adolescent idiopathic scoliosis (AIS).

SUMMARY OF BACKGROUND DATA

Infection is a morbid complication after spinal fusion. The incidence of SSI after pediatric spinal fusion is likely underestimated; the use of a national database allows for a comprehensive assessment of this rare outcome.

MATERIALS AND METHODS

The PearlDiver Database was used to identify AIS patients who underwent primary instrumented spinal fusion between 2010 and 2019 and relevant patient records were queried to identify infections within 7, 30, and 90 postoperative days. Patients with nonidiopathic scoliosis were excluded. Logistic regression was used to evaluate risk factors associated with postoperative infection.

RESULTS

Out of 9801 patients who underwent primary fusion for AIS, 44 patients (0.4%) developed an infection within 7 postoperative days. The 30 days and 90 days incidences were 1.9% and 2.7%, respectively. Within 90 days, 154 (57.7%) of the patients with infection had undergone reoperation, of whom 72 underwent multiple reoperations. Obesity and male sex ( P < 0.05) were significantly associated with postoperative infection. The length of fusion was not a significant factor in the development of SSI ( P > 0.05). Eleven patients underwent an operation requiring hardware removal within 90 days. There were no significant factors associated with those undergoing hardware removal compared with those undergoing surgical debridement.

CONCLUSIONS

The study identified a 2.7% 90 days incidence of SSI after posterior spinal fusion for AIS, with 57.7% of all infections requiring a return to the operating room. Preoperative patient-related characteristics associated with increased risk of postoperative SSI were male sex and obesity. The current study can be used to provide preoperative counseling regarding the risk of this postoperative complication.

LEVEL OF EVIDENCE

Level III.

Significance of surgical first assistant expertise for surgical site infection prevention: Propensity score matching analysis

Surgical site infection (SSI) is one of the most common postoperative complications in patients undergoing major operations, such as spinal fusion surgery, and a major contributor to patient morbidity and mortality. SSI is considered the most preventable type of infection; however, the risk of SSI is multifactorial. This study aimed to determine the extent to which the expertise of the surgical first assistant (SFA) affected SSI rates. We retrospectively reviewed 528 patients at a single institution who underwent lumbar spine fusion surgery via the posterior approach performed by a single surgeon between January 2012 and May 2020. The SFAs participating in the surgeries were classified into 2 groups: a certified neurosurgery specialist and relatively less experienced neurosurgery resident trainees. To reduce potential selection bias and confounding factors, propensity score matching was performed between the 2 groups. In 170 of the 528 lumbar spine fusion surgeries, the SFA was a certified neurosurgery specialist. In the other 358 surgeries, the SFA was a resident trainee. Seventeen patients met the SSI criteria. The SSI rate was significantly different between the 2 groups (0.6% (1 patient) and 4.5% (16 patients) in the certified specialist and resident trainee groups, respectively; P = .02). After propensity score matching, 170 paired patients were selected. After adjusting for confounding factors, SFAs that were certified neurosurgery specialists were associated with a lower likelihood of SSI (adjusted OR 0.09; 95% CI, 0.01 to 0.79; P = .029) than SFAs that were neurosurgery residents. A higher level of SFA expertise was significantly associated with a lower overall SSI rate in lumbar spine fusion surgeries. It is difficult to predict the incidence of SSI; however, this finding suggests the importance of SFA expertise in preventing SSI.

Unexpected intraoperative positive culture (UIPC) in presumed aseptic revision spine surgery: a systematic review and meta-analysis

BACKGROUND CONTEXT

Unexpected intraoperative positive culture (UIPC) has recently become increasingly common in revision spine surgery, being implicated as an etiological factor in revision spine surgery indications such as implant failure or pseudoarthrosis.

PURPOSE

Utilizing the available literature, this study aimed to investigate the prevalence of UIPC, and its clinical importance in patients following presumed aseptic revision spine surgery.

STUDY DESIGN

Meta-analysis and systematic review.

METHODS

Multiple databases and reference articles were searched until May 2022. The primary outcome was the pooled rate of UIPC, and the secondary outcomes were the microbiological profile of UIPC, the risk factors of UIPC, and the clinical fate of UIPC.

RESULTS

Twelve studies were eligible for meta-analysis, with a total of 1,108 patients. The pooled rate of UIPC was 24.3% (95% CI=15.8%-35.5%) in adult patients, and 43.2% (95% CI=32.9%-54.2%) in pediatric patients. The UIPC rate was higher when both conventional wound culture and sonication were used together compared to sonication alone or conventional wound culture alone. The rates were 28.9%, 23.6%, and 15.5 %, respectively. In adult and pediatric patients, the most commonly cultured organism was Cutibacterium acnes (42.5% vs 57.7%), followed by coagulase-negative Staphylococcus (39.9% vs 30.5%). Male patients had a higher rate of UIPC (OR= 2.6, 95% CI=1.84-3.72, p<.001), as did patients with a longer fusion construct (MD=0.76, 95% CI=0.27-1.25, p<.001).

CONCLUSIONS

The pooled rate of UIPC in aseptic spine revision surgery was 24.3% and 43.2% in adult and pediatric patients respectively. The most common organisms were C. acnes and coagulase-negative Staphylococcus. The impact of UIPC on patients` clinical outcomes is not fully understood. We are not able to recommend routine culture in revision spine surgery, however, adding sonication may aid in the diagnosis of UIPC. There is not enough evidence to recommend specific treatment strategies at this time, and further studies are warranted.

Cutibacterium spp. Infections after Instrumented Spine Surgery Have a Good Prognosis Regardless of Rifampin Use: A Cross-Sectional Study

Infection after spinal instrumentation (IASI) by Cutibacterium spp. is being more frequently reported. The aim of this study was to analyse the incidence, risk factors, clinical characteristics, and outcome of a Cutibacterium spp. IASI (CG) compared with non-Cutibacterium IASI (NCG) infections, with an additional focus on the role of rifampin in the treatment. All patients from a multicentre, retrospective, observational study with a confirmed IASI between January 2010 and December 2016 were divided into two groups: (CG and NCG) IASI. Baseline, medical, surgical, infection treatment, and follow-up data were compared for both groups. In total, 411 patients were included: 27 CG and 384 NCG. The CG patients were significantly younger. They had a longer median time to diagnosis (23 vs. 13 days) (p = 0.025), although 55.6% debuted within the first month after surgery. Cutibacterium patients were more likely to have the implant removed (29.6% vs. 12.8%; p = 0.014) and received shorter antibiotic regimens (p = 0.014). In 33% of Cutibacterium cases, rifampin was added to the baseline therapy. None of the 27 infections resulted in treatment failure during follow-up regardless of rifampin use. Cutibacterium spp. is associated with a younger age and may cause both early and late IASIs. In our experience, the use of rifampin to improve the outcome in the treatment of a Cutibacterium spp. IASI is not relevant since, in our series, none of the cases had therapeutic failure regardless of the use of rifampin.

Health Care Utilization and Associated Economic Burden of Postoperative Surgical Site Infection after Spinal Surgery with Follow-Up of 24 Months

BACKGROUND

 Surgical site infection (SSI) may lead to vertebral osteomyelitis, diskitis, paraspinal musculoskeletal infection, and abscess, and remains a significant concern in postoperative management of spinal surgery. SSI is associated with greater postoperative morbidity and increased health care payments.

METHODS

 We conducted a retrospective analysis using MarketScan to identify health care utilization payments and risk factors associated with SSI that occurs postoperatively. Known patient- or procedure-related risk factors were searched across those receiving spine surgery who developed postoperative infection.

RESULTS

 A total of 33,061 patients who developed infection after spinal surgery were identified in Marketscan. Overall payments at 6 months, including index hospitalization for those with infection, were $53,573 and $46,985 for the cohort with no infection. At 24 months, the infection group had overall payments of $83,280 and $66,221 for no infection. Risk factors with largest effect size most likely to contribute to infection versus no infection were depression (4.6%), diabetes (3.7), anemia (3.3%), two or more levels (2.8%), tobacco use (2.2%), trauma (2.1%), neoplasm (1.8%), congestive heart failure (1.3%), instrumentation (1.1%), renal failure (0.9%), intravenous drug use (0.8%), and malnutrition (0.5%).

CONCLUSIONS

 SSIs were associated with significant health care utilization payments at 24 months of follow-up. The following clinical and procedural risk factors appear to be predictive of postoperative SSI: depression, diabetes, anemia, two or more levels, tobacco use, trauma, neoplasm, congestive heart failure, instrumentation, renal failure, intravenous drug use, and malnutrition. Interpretation of modifiable and nonmodifiable risk factors for infection informs surgeons of expected postoperative course and preoperative risk for this most common and deleterious postoperative complication to spinal surgery.

Risk and economic burden of surgical site infection following spinal fusion in adults

BACKGROUND

Spinal fusion surgery (SFS) is one of the most common operations in the United States, >450,000 SFSs are performed annually, incurring annual costs >$10 billion.

OBJECTIVES

We used a nationwide longitudinal database to accurately assess incidence and payments associated with management of postoperative infection following SFS.

METHODS

We conducted a retrospective, observational cohort analysis of 210,019 patients undergoing SFS from 2014 to 2018 using IBM MarketScan commercial and Medicaid-Medicare databases. We assessed rates of superficial/deep incisional SSIs, from 3 to 180 days after surgery using Cox proportional hazard regression models. To evaluate adjusted payments for patients with/without SSIs, adjusted for inflation to 2019 Consumer Price Index, we used generalized linear regression models with log-link and γ distribution.

RESULTS

Overall, 6.6% of patients experienced an SSI, 1.7% superficial SSIs and 4.9% deep-incisional SSIs, with a median of 44 days to presentation for superficial SSIs and 28 days for deep-incisional SSIs. Selective risk factors included surgical approach, admission type, payer, and higher comorbidity score. Postoperative incremental commercial payments for patients with superficial SSI were $20,800 at 6 months, $26,937 at 12 months, and $32,821 at 24 months; incremental payments for patients with deep-incisional SSI were $59,766 at 6 months, $74,875 at 12 months, and $93,741 at 24 months. Corresponding incremental Medicare payments for patients with superficial incisional at 6, 12, 24-months were $11,044, $17,967, and $24,096; while payments for patients with deep-infection were: $48,662, $53,757, and $73,803 at 6, 12, 24-months.

CONCLUSIONS

We identified a 4.9% rate of deep infection following SFS, with substantial payer burden. The findings suggest that the implementation of robust evidence-based surgical-care bundles to mitigate postoperative SFS infection is warranted.

Safety and efficacy of negative pressure wound therapy in treating deep surgical site infection after lumbar surgery

PURPOSE

To evaluate the efficacy and safety of negative pressure wound therapy (NPWT) for post-operative deep surgical site infection (SSI) after posterior instrumented spinal surgery.

METHODS

We retrospectively compared the clinical outcomes of NPWT with standard debridement for deep SSI after posterior instrumented spinal surgery from 2012 to 2020 in our department. The primary outcomes were peri-operative characteristics including positive organism results, duration of fever, and visual analogue scale (VAS) pain scores three days after re-operation. The secondary outcomes were post-operative characteristics including implant infection recurrence, implant retention rate, duration of hospitalization, and VAS at discharge. Pearson's chi-squared analysis (categorical) and Student's t test (continuous) were used to determine the differences.

RESULTS

Thirty-four patients were included, of which 19 underwent NPWT, and 15 underwent standard debridement. Patients in the NPWT group all significantly improved primary outcomes including duration of fever after re-operation (0.95 ± 1.13 vs 4.07 ± 5.35, P = 0.001), positive organism results (14 of 19 vs 2 of 15, P < 0.01), and VAS at 3 days after re-operation (2.58 ± 0.69 vs 3.40 ± 1.06, P < 0.05). Patients in NPWT group exhibited significant decrease in implant infection recurrence (0 of 19 vs 5 of 15, P < 0.01), implant retention rate (19 of 19 vs 10 of 15, P < 0.01), duration of hospitalization (27.74 ± 10.95 vs 37.67 ± 13.67, P < 0.01).

CONCLUSIONS

NPWT is a feasible and safe treatment option for deep SSI after posterior instrumented spinal surgery.

Clinical Outcomes at One-year Follow-up for Patients With Surgical Site Infection After Spinal Fusion

STUDY DESIGN

Retrospective case-control study.

OBJECTIVE

To compare health-related quality of life outcomes at one-year follow-up between patients who did and did not develop surgical site infection (SSI) after thoracolumbar spinal fusion.

SUMMARY OF BACKGROUND DATA

SSI is among the most common healthcare-associated complications. As healthcare systems increasingly emphasize the value of delivered care, there is an increased need to understand the clinical impact of SSIs.

MATERIALS AND METHODS

A retrospective 3:1 (control:SSI) propensity-matched case-control study was conducted for adult patients who underwent thoracolumbar fusion from March 2014 to January 2020 at a single academic institution. Exclusion criteria included less than 18 years of age, incomplete preoperative and one-year postoperative patient-reported outcome measures, and revision surgery. Continuous and categorical data were compared via independent t tests and χ 2 tests, respectively. Intragroup analysis was performed using paired t tests. Regression analysis for ∆ patient-reported outcome measures (postoperative minus preoperative scores) controlled for demographics. The α was set at 0.05.

RESULTS

A total of 140 patients (105 control, 35 SSI) were included in final analysis. The infections group had a higher rate of readmission (100% vs. 0.95%, P <0.001) and revision surgery (28.6% vs. 12.4%, P =0.048). Both groups improved significantly in Physical Component Score (control: P =0.013, SSI: P =0.039), Oswestry Disability Index (control: P <0.001, SSI: P =0.001), Visual Analog Scale (VAS) Back (both, P <0.001), and VAS Leg (control: P <0.001, SSI: P =0.030). Only the control group improved in Mental Component Score ( P <0.001 vs. SSI: P =0.228), but history of a SSI did not affect one-year improvement in ∆MCS-12 ( P =0.455) on regression analysis. VAS Leg improved significantly less in the infection group (-1.87 vs. -3.59, P =0.039), which was not significant after regression analysis (β=1.75, P =0.050).

CONCLUSION

Development of SSI after thoracolumbar fusion resulted in increased revision rates but did not influence patient improvement in one-year pain, functional disability, or physical and mental health status.

Incidence, Management and Outcome of Delayed Deep Surgical Site Infection Following Spinal Deformity Surgery: 20-Year Experience at a Single Institution

STUDY DESIGN

A retrospective study.

OBJECTIVES

To investigate the incidence, management and outcome of delayed deep surgical site infection (SSI) after the spinal deformity surgery.

METHODS

This study reviewed 5044 consecutive patients who underwent spinal deformity corrective surgery and had been followed over 2 years. Delayed deep SSI were defined as infection involving fascia and muscle and occurring >3 months after the initial procedure. An attempt to retain the implant were initially made for all patients. If the infection failed to be eradicated, the implant removal should be put off until solid fusion was confirmed, usually more than 2 years after the initial surgery. Radiographic data at latest follow-up were compared versus that before implant removal.

RESULTS

With an average follow-up of 5.3 years, 56 (1.1%) patients were diagnosed as delayed deep SSI. Seven (12.5%) patients successfully retained instrumentation and there were no signs of recurrence during follow-up (average 3.4 years). The remaining patients, because of persistent or recurrent infection, underwent implant removal 2 years or beyond after the primary surgery, and solid fusion was detected in any case. However, at a minimum 1-year follow-up (average 3.9 years), an average loss of 9° in the thoracic curve and 8° in the thoracolumbar/lumbar curves was still observed.

CONCLUSIONS

Delayed deep SSI was rare after spinal deformity surgery. To eradicate infection, complete removal of implant may be required in the majority of delayed SSI. Surgeons must be aware of high likelihood of deformity progression after implant removal, despite radiographic solid fusion.

Tobacco Use Is Associated With Increased 90-Day Readmission Among Patients Undergoing Surgery for Degenerative Spine Disease

STUDY DESIGN

Retrospective database study.

OBJECTIVE

Tobacco use is associated with complications after surgical procedures, including poor wound healing, surgical site infections, and cardiovascular events. We used the Nationwide Readmissions Database (NRD) to determine if tobacco use is associated with increased 30- and 90-day readmission among patients undergoing surgery for degenerative spine disorders.

METHODS

Patients who underwent elective spine surgery were identified in the NRD from 2010 to 2014. The study population included patients with degenerative spine disorders treated with discectomy, fusion, or decompression. Descriptive and multivariate logistic regression analyses were performed to identify patient and hospital factors associated with 30- and 90-day readmission, with significance set at P value <.001.

RESULTS

Within 30 days, 4.8% of patients were readmitted at a median time of 9 days. The most common reasons for 30-day readmission were postoperative infection (12.5%), septicemia (3.5%), and postoperative pain (3.0%). Within 90 days, 7.3% were readmitted at a median time of 18 days. The most common reasons for 90-day readmission were postoperative infection (9.6%), septicemia (3.5%), and pneumonia (2.3%). After adjustment for patient and hospital characteristics, tobacco use was independently associated with readmission at 90 days (odds ratio 1.05, 95% confidence interval 1.03-1.07, P < .0001) but not 30 days (odds ratio 1.02, 95% confidence interval 1.00-1.05, P = .045).

CONCLUSIONS

Tobacco use is associated with readmission within 90 days after cervical and thoracolumbar spine surgery for degenerative disease. Tobacco use is a known risk factor for adverse health events and therefore should be considered when selecting patients for spine surgery.

Does Cigarette Smoking Affect Cervical Laminoplasty Clinical and Radiologic Outcomes?

STUDY DESIGN

Retrospective review.

OBJECTIVE

This study aimed to investigate if smokers have both poorer early clinical and radiologic outcomes in cervical laminoplasty when compared with nonsmokers.

SUMMARY OF BACKGROUND DATA

Cigarette smoking had been reported to increase rates of pseudoarthrosis following spinal instrumentation with fusion.

METHODOLOGY

A retrospective review of all patients who underwent open-door cervical laminoplasty was performed. Nurick, neck pain visual analog scale, and neck disability index scores were reviewed. Cervical lordosis, range of motion (ROM), and intervertebral disc height were measured. The rates and reasons for revision surgery were recorded and classified according to the etiology of laminoplasty revision surgery.

RESULTS

Sixty patients were recruited, of which 20 patients (18 males, 2 females) were smokers and 40 patients (27 males, 13 females) were nonsmokers. There was no statistically significant difference between smokers and nonsmokers in preoperative and postoperative visual analog scale, neck disability index, and Nurick scores. A trend was noted toward a greater postoperative reduction in cervical lordosis (13±8 vs. 11±11 degrees). Furthermore, 41% of smokers versus 30% in nonsmokers had >10% loss of postoperative ROM, and 59% smokers versus 50% nonsmokers had >5% loss of postoperative ROM.Postoperative complications and intervertebral disc deterioration were similar in both groups. A higher reoperation rate was noted in smokers with 6 smokers (30%) as compared with 4 nonsmokers (10%), although this did not reach statistical significance. Among the smokers, 4 (20%) were because of cervical disease progression while 2 were technique related. In nonsmokers, all 4 (10%) were because of cervical disease progression.

CONCLUSION

This study showed that while there was a nonstatistically significant trend noted toward higher rates of revision surgery in smokers, the laminoplasty outcomes were not significantly poorer in smokers. In heavy smokers with multilevel cervical myelopathy, laminoplasty may be the treatment of choice over anterior spinal decompression and fusion where a high risk of pseudoarthrosis is anticipated.

Is the Use of Intraoperative 3D Navigation for Thoracolumbar Spine Surgery a Risk Factor for Post-Operative Infection?

Pedicle screw fixation is a technique used to provide rigid fixation in thoracolumbar spine surgery. Safe intraosseous placement of pedicle screws is necessary to provide optimal fixation as well as to avoid damage to adjacent anatomic structures. Despite the wide variety of techniques available, none thus far has been able to fully eliminate the risk of malpositioned screws. Intraoperative 3-dimensional navigation (I3DN) was developed to improve accuracy in the placement of pedicle screws. To our knowledge, no previous studies have investigated whether infection rates are higher with I3DN. A single-institution, retrospective study of patients age > 18 undergoing thoracolumbar fusion and instrumentation was carried out and use of I3DN was recorded. The I3DN group had a significantly greater rate of return to the operating room for culture-positive incision and drainage (17 (4.1%) vs. 1 (0.6%), p = 0.025). In multivariate analysis, the use of I3DM did not reach significance with an OR of 6.49 (0.84−50.02, p = 0.073). Post-operative infections are multifactorial and potential infection risks associated with I3DN need to be weighed against the safety benefits of improved accuracy of pedicle screw positioning.

Lack of association of post-discharge prophylactic antibiotics with decreased risk of surgical site infection following spinal fusion

OBJECTIVES

To determine the prevalence and factors associated with post-discharge prophylactic antibiotic use after spinal fusion and whether use was associated with decreased risk of surgical site infection (SSI).

METHODS

Persons aged 10-64 years undergoing spinal fusion between 1 January 2010 and 30 June 2015 were identified in the MarketScan Commercial Database. Complicated patients and those coded for infection from 30 days before to 2 days after the surgical admission were excluded. Outpatient oral antibiotics were identified within 2 days of surgical discharge. SSI was defined using ICD-9-CM diagnosis codes within 90 days of surgery. Generalized linear models were used to determine factors associated with post-discharge prophylactic antibiotic use and with SSI.

RESULTS

The cohort included 156 446 fusion procedures, with post-discharge prophylactic antibiotics used in 9223 (5.9%) surgeries. SSIs occurred after 2557 (1.6%) procedures. Factors significantly associated with post-discharge prophylactic antibiotics included history of lymphoma, diabetes, 3-7 versus 1-2 vertebral levels fused, and non-infectious postoperative complications. In multivariable analysis, post-discharge prophylactic antibiotic use was not associated with SSI risk after spinal fusion (relative risk 0.98; 95% CI 0.84-1.14).

CONCLUSIONS

Post-discharge prophylactic oral antibiotics after spinal fusion were used more commonly in patients with major medical comorbidities, more complex surgeries and those with postoperative complications during the surgical admission. After adjusting for surgical complexity and infection risk factors, post-discharge prophylactic antibiotic use was not associated with decreased SSI risk. These results suggest that prolonged prophylactic antibiotic use should be avoided after spine surgery, given the lack of benefit and potential for harm.

Diabetes Is Predictive of Postoperative Outcomes and Readmission Following Posterior Lumbar Fusion

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The present study analyzes complication rates and episode-based costs for patients with and without diabetes mellitus (DM) following posterior lumbar fusion (PLF).

METHODS

PLF cases at a single institution from 2008 to 2016 were queried (n = 3226), and demographic and perioperative data were analyzed. Patients with and without the diagnosis of DM were compared using chi-square, Student's t test, and multivariable regression modeling.

RESULTS

Patients with diabetes were older (63.10 vs 56.48 years, P < .001) and possessed a greater number of preoperative comorbidities (47.84% of patients had Elixhauser Comorbidity Index >0 vs 42.24%, P < .001) than did patients without diabetes. When controlling for preexisting differences, diabetes remained a significant risk factor for prolonged length of stay (OR = 1.59, 95% CI 1.26-2.01, P < .001), intensive care unit stay (OR = 1.52, 95% CI 1.07-2.17, P = .021), nonhome discharge (OR = 1.86, 95% CI 1.46-2.37, P < .001), 30-day readmission (OR = 2.15, 95% CI 1.28-3.60, P = .004), 90-day readmission (OR = 1.65, 95% CI 1.05-2.59, P = .031), 30-day emergency room visit (OR = 2.15, 95% CI 1.27-3.63, P = .004), and 90-day emergency room visit (OR = 2.27, 95% CI 1.41-3.65, P < .001). Cost modeling controlling for overall comorbidity burden demonstrated that diabetes was associated with a $1709 increase in PLF costs (CI $344-$3074, P = .014).

CONCLUSIONS

The present findings indicate a correlation between diabetes and a multitude of postoperative adverse outcomes and increased costs, thus illustrating the substantial medical and financial burdens of diabetes for PLF patients. Future studies should explore preventive measures that may mitigate these downstream effects.

Medicosurgical management of deep wound infections after thoracolumbar instrumentation: risk factors of poor outcomes

BACKGROUND

Surgical site infection (SSI) after thoracolumbar osteosynthesis is a common complication. Its management relies on surgical revision and antibiotic therapy, but treatment failure is not uncommon. The aim of our study was to assess the frequency of SSI management failure and its risk factors.

METHODS

A retrospective study of patients hospitalized from 2011 to 2019 at the University Hospital of Caen was carried out. The infection rate and the time to onset of failure were assessed over a minimum follow-up of 1 year. Treatment failure was defined as the occurrence of a new intervention in the spine in the year following the end of antibiotic therapy, the establishment of long-term suppressive antibiotic therapy, or death from any cause within 1 year of the end of antibiotic therapy. We compared the treatment failure group with the treatment success group to determine risk factors for treatment failure.

RESULTS

A total of 2881 patients underwent surgery during the study period, and 92 developed an SSI, corresponding to an SSI rate of 3.19%. Thirty-six percent of the patients with an SSI presented treatment failure. The median time to failure was 31 days. On multivariate analysis, diabetes mellitus was identified as a risk factor for treatment failure, whereas prolonged postoperative drainage for 4 to 5 days was a protective factor.

CONCLUSIONS

The number of failures was significant, and failure occurred mainly during the early phase. To decrease the risk of treatment failure, prolonged duration of postoperative drainage seems to be helpful. Additionally, as diabetes is a risk factor for treatment failure, good control of glycemia in these patients might impact their outcomes.

A Novel Technique for Treating Early Deep Surgical Site Infection After Posterior Lumbar Fusion with Instrumentation

OBJECTIVE

To introduce a novel technique of using incisional vacuum-assisted closure (VAC) after 1-stage incision suture combined with closed suction irrigation system (CSIS) for treating early deep surgical site infection (SSI) after posterior lumbar fusion with instrumentation and to compare it with traditional CSIS.

METHODS

This was a retrospective study. Patients with early deep SSI after posterior lumbar fusion with instrumentation from January 2013 to May 2020 who were treated by meticulous debridement followed by either CSIS or incisional VAC after 1-stage incision suture combined with CSIS were identified. The demographic characteristics, treatment features, and outcomes were analyzed and compared between the 2 treatment methods.

RESULTS

A total of 48 patients (48/5016, 0.96%) developed early deep SSI, 46 of whom were enrolled in this study. This included 24 patients in the CSIS group (group 1) and 22 patients in the incisional VAC after 1-stage incision suture combined with CSIS group (group 2). All patients received follow-up, with an average of 19.7 months (range, 13-30 months). There were no significant differences in demographic characteristics in both groups (P > 0.05). The number of VAC foam dressing or ordinary dressing changes (P < 0.001), number of debridements (P = 0.028), intravenous antibiotic duration (P = 0.042), oral antibiotic duration (P = 0.019), and hospital stay (P = 0.029) in group 1 were significantly higher than those in group 2. The irrigation duration in group 1 was significantly shorter than that in group 2 (P = 0.007). All patients were eventually cured with satisfactory outcomes.

CONCLUSIONS

Compared with CSIS, incisional VAC after 1-stage incision suture combined with CSIS may be recommended considering that it has fewer dressing changes, fewer debridements, longer irrigation duration, shorter duration of antibiotic use, shorter hospital stay, and more convenient nursing care.

Diabetes is associated with greater leg pain and worse patient-reported outcomes at 1 year after lumbar spine surgery

Although patients with diabetes reportedly have more back pain and worse patient-reported outcomes than those without diabetes after lumbar spine surgery, the impact of diabetes on postoperative recovery in pain or numbness in other regions is not well characterized. In this study, the authors aimed to elucidate the impact of diabetes on postoperative recovery in pain/numbness in four areas (back, buttock, leg, and sole) after lumbar spine surgery. The authors retrospectively reviewed 993 patients (152 with diabetes and 841 without) who underwent decompression and/or fixation within three levels of the lumbar spine at eight hospitals during April 2017–June 2018. Preoperative Numerical Rating Scale (NRS) scores in all four areas, Oswestry Disability Index (ODI), and Euro quality of life 5-dimension (EQ-5D) were comparable between the groups. The diabetic group showed worse ODI/EQ-5D and greater NRS scores for leg pain 1 year after surgery than the non-diabetic group. Although other postoperative NRS scores tended to be higher in the diabetic group, the between-group differences were not significant. Diabetic neuropathy caused by microvascular changes may induce irreversible nerve damage especially in leg area. Providers can use this information when counseling patients with diabetes about the expected outcomes of spine surgery.

Impact of intrawound vancomycin powder on prevention of surgical site infection after posterior spinal surgery

OBJECTIVE

Surgical site infection (SSI) after posterior spinal surgery is one of the severe complications that may occur despite administration of prophylactic antibiotics and the use of intraoperative aseptic precautions. The use of intrawound vancomycin powder for SSI prevention is still controversial, with a lack of high-quality and large-scale studies. The purpose of this retrospective study using a propensity score-matched analysis was to clarify whether intrawound vancomycin powder prevents SSI occurrence after spinal surgery.

METHODS

The authors analyzed 1261 adult patients who underwent posterior spinal surgery between 2010 and 2018 (mean age 62.3 years; 506 men, 755 women; follow-up period at least 1 year). Baseline and surgical data were assessed. After a preliminary analysis, a propensity score model was established with adjustments for age, sex, type of disease, and previously reported risk factors for SSI. The SSI rates were compared between patients with intrawound vancomycin powder treatment (vancomycin group) and those without (control group).

RESULTS

In a preliminary analysis of 1261 unmatched patients (623 patients in the vancomycin group and 638 patients in the control group), there were significant differences between the groups in age (p = 0.041), body mass index (p = 0.013), American Society of Anesthesiologists classification (p < 0.001), malnutrition (p = 0.001), revision status (p < 0.001), use of steroids (p = 0.019), use of anticoagulation (p = 0.033), length of surgery (p = 0.003), estimated blood loss (p < 0.001), and use of instrumentation (p < 0.001). There was no significant difference in SSI rates between the vancomycin and control groups (21 SSIs [3.4%] vs 33 SSIs [5.2%]; OR 0.640, 95% CI 0.368-1.111; p = 0.114). Using a one-to-one propensity score-matched analysis, 444 pairs of patients from the vancomycin and control groups were selected. There was no significant difference in the baseline and surgical data, except for height (p = 0.046), between both groups. The C-statistic for the propensity score model was 0.702. In the score-matched analysis, 12 (2.7%) and 24 (5.4%) patients in the vancomycin and control groups, respectively, developed SSIs (OR 0.486, 95% CI 0.243-0.972; p = 0.041). There were no systemic complications related to the use of vancomycin.

CONCLUSIONS

The current study showed that intrawound vancomycin powder was useful in reducing the risk of SSI after posterior spinal surgery by half, without adverse events. Intrawound vancomycin powder use is a safe and effective procedure for SSI prevention.

Risk factors for deep surgical site infection following posterior instrumented fusion for degenerative diseases in the thoracic and/or lumbar spine: a multicenter, observational cohort study of 2913 consecutive cases

PURPOSE

Surgical site infection (SSI) is one of the most devastating complications following spinal instrumented fusion surgeries because it may lead to a significant increase in morbidity, mortality, and poor clinical outcomes. Identifying the risk factors for SSI can help in developing strategies to reduce its occurrence. However, data on the risk factors for SSI in degenerative diseases are limited. This study aimed to identify risk factors for deep SSI following posterior instrumented fusion for degenerative diseases in the thoracic and/or lumbar spine in adult patients.

METHODS

This was a multicenter, observational cohort study conducted at 10 study hospitals between July 2010 and June 2015. The subjects were consecutive adult patients who underwent posterior instrumented fusion surgery for degenerative diseases in the thoracic and/or lumbar spine and developed SSI. Detailed patient-specific and procedure-specific potential risk variables were prospectively recorded using a standardized data collection chart and retrospectively reviewed.

RESULTS

Of the 2913 enrolled patients, 35 developed postoperative deep SSI (1.2%). Multivariable regression analysis identified three independent risk factors: male sex (P = 0.002) and American Society of Anesthesiologists (ASA) score of ≥ 3 (P = 0.003) as patient-specific risk factors, and operation including the thoracic spine (P = 0.018) as a procedure-specific risk factor.

CONCLUSION

Thoracic spinal surgery, an ASA score of ≥ 3, and male sex were risk factors for deep SSI after routine thoracolumbar instrumented fusion surgeries for degenerative diseases. Awareness of these risk factors can enable surgeons to develop a more appropriate management plan and provide better patient counseling.

Deep Brain Stimulation-Related Surgical Site Infections: A Systematic Review and Meta-Analysis

BACKGROUND

Over the last decades, the increased use of deep brain stimulation (DBS) has raised concerns about the potential adverse health effects of the treatment. Surgical site infections (SSIs) following an elective surgery remain a major challenge for neurosurgeons. Few studies have examined the prevalence and risk factors of DBS-related complications, particularly focusing on SSIs.

OBJECTIVES

We systematically searched published literature, up to June 2020, with no language restrictions.

MATERIALS AND METHODS

Eligible were studies that examined the prevalence of DBS-related SSIs, as well as studies that examined risk and preventive factors in relation to SSIs. We extracted information on study characteristics, follow-up, exposure and outcome assessment, effect estimate and sample size. Summary odds ratios (sOR) and 95% confidence intervals (CI) were calculated from random-effects meta-analyses; heterogeneity and small-study effects were also assessed.

RESULTS

We identified 66 eligible studies that included 12,258 participants from 27 countries. The summary prevalence of SSIs was estimated at 5.0% (95% CI: 4.0%-6.0%) with higher rates for dystonia (6.5%), as well as for newer indications of DBS, such as epilepsy (9.5%), Tourette syndrome (5.9%) and OCD (4.5%). Similar prevalence rates were found between early-onset and late-onset hardware infections. Among risk and preventive factors, the perioperative implementation of intra-wound vancomycin was associated with statistically significantly lower risk of SSIs (sOR: 0.26, 95% CI: 0.09-0.74). Heterogeneity was nonsignificant in most meta-analyses.

CONCLUSION

The present study confirms the still high prevalence of SSIs, especially for newer indications of DBS and provides evidence that preventive measures, such as the implementation of topical vancomycin, seem promising in reducing the risk of DBS-related SSIs. Large clinical trials are needed to confirm the efficacy and safety of such measures.

Hypoalbuminemia Increased the Length of Stay in the Treatment of Postoperative Acute Surgical Site Infection in Spinal Surgery

STUDY DESIGN

Multicenter retrospective study.

OBJECTIVE

The aim of this study was to identify specific risk factors for increased length of stay (LOS) in the management of acute surgical site infection (SSI) following spinal surgery.

SUMMARY OF BACKGROUND DATA

Postoperative SSI is a serious complication of spinal surgery and is known to be associated with increased LOS and additional cost. Although many risk factors contribute to the development of SSI following spinal surgery, little is known about risk factors associated with the treatment of SSI that contribute to increased LOS.

METHODS

Patients at two institutions experiencing deep SSI following spinal surgery between January 2009 and December 2016 were identified. The patients were divided into two groups depending upon the median LOS attributable to SSI. The effects of patient characteristics, comorbidities, disease history, and invasiveness of the elective surgery on the risk of increased LOS were determined using univariate analyses and multivariate logistic regression.

RESULTS

Of the 1656 spinal surgery cases, 40 (2.4%) experienced deep SSI. The median LOS was 67 days. Multivariate logistic regression analysis revealed that hypoalbuminemia during hospitalization was associated with increased LOS (odds ratio 0.042, confidence interval 0.005-0.342; P = 0.003). We determined the appropriate diagnostic cutoff of hypoalbuminemia during hospitalization using receiver-operating characteristic curves. A serum albumin level <3.1 g/dL (sensitivity, 86.4%; specificity, 75.0%; area under the curve, 0.84) was indicative of a longer hospital stay.

CONCLUSION

Low serum albumin level during hospitalization was an independent risk factor for increased LOS in the treatment of SSI following spinal surgery. When the serum albumin level is <3.1 g/dL in patients with SSI, we should consider interventions aimed at correcting this hypoalbuminemia.

LEVEL OF EVIDENCE

4.

Negative pressure wound therapy in spinal fusion patients

Post-operative wound complications are some of the most common acute complications following spine surgery. These surgical site infections (SSI) contribute to increased healthcare related costs. Negative pressure wound therapy (NPWT) has long been used for treatment of soft tissue injury or defects. NPWT may reduce the incident of SSI following spinal fusion procedures; however, its potential applications need further clarification. Thus, we conducted a retrospective analysis of two cohorts to compare NPWT to traditional sterile dressings following spinal fusions in regards to post-operative outcomes. Following institutional review board approval, 42 patients who had a NPWT were matched by type of surgery to 42 patients who had traditional dressings. A retrospective chart-review was completed. Outcome measures, particularly SSI and need for reoperation, were analyzed using one-way ANOVA for both univariate and multivariate analysis. When controlled for sex and body-mass index, the use of a NPWT was independently correlated with decreased SSI (P = .035). Superficial dehiscence, seroma, need for additional outpatient care, and need for operative revision were all found to occur at higher rates in the traditional dressing cohort. Closed incisional negative pressure wound therapy provides a cost-effective method of decreasing surgical site infection for posterior elective spine surgeries.

Healthcare resources attributable to methicillin-resistant Staphylococcus aureus orthopedic surgical site infections

The number of orthopedic surgeries is increasing as populations steadily age, but surgical site infection (SSI) rates remain relatively consistent. This study aimed to quantify the healthcare resources attributable to methicillin-resistant Staphylococcus aureus (MRSA) SSIs in orthopedic surgical patients. The analysis was conducted using a national claims database comprising data from almost all Japanese residents. We examined patients who underwent any of the following surgeries between April 2012 and March 2018: amputation (AMP), spinal fusion (FUSN), open reduction of fracture (FX), hip prosthesis (HPRO), knee prosthesis (KPRO), and laminectomy (LAM). Propensity score matching was performed to identify non-SSI control patients, and generalized estimating equations were used to estimate the differences in outcomes between the case and control groups. The numbers of MRSA SSI cases (infection rates) ranged from 64 (0.03%) to 1,152 (2.33%). MRSA SSI-attributable increases in healthcare expenditure ranged from $11,630 ($21,151 vs. $9,521) for LAM to $35,693 ($50,122 vs. $14,429) for FX, and increases in hospital stay ranged from 40.6 days (59.2 vs. 18.6) for LAM to 89.5 days (122.0 vs. 32.5) for FX. In conclusion, MRSA SSIs contribute to substantial increases in healthcare resource utilization, emphasizing the need to implement effective infection prevention measures for orthopedic surgeries.

Does preoperative prognostic nutrition index predict surgical site infection after spine surgery?

PURPOSE

Malnutrition is reported as one of the risk factors for surgical site infection (SSI). The prognostic nutritional index (PNI) is a simple method for nutritional evaluation. However, little is known about the relationship between SSI and the PNI in patients after spine surgery. We aimed to determine independent predictors of SSI after spine surgery.

METHODS

We analyzed 1115 patients who underwent spine surgery (369 males, 746 females, mean age 56 years, follow-up period: at least 1 year). Patients were divided into SSI and non-SSI groups. Preoperative risk factors, including PNI (10 × serum albumin [g/dL] + 0.005 × total lymphocyte count [/μL]), were assessed.

RESULTS

Postoperatively, 43 patients (3.9%) experienced SSI. Univariate analysis showed that preoperative PNI (48.5 vs 51.7; p < 0.01), revision status (p < 0.05), male sex (p < 0.01), body mass index (BMI) (p < 0.05), and usage of anticoagulant agents (p < 0.05) differed significantly between the SSI and non-SSI groups. Multivariate logistic regression analysis showed that preoperative PNI (odds ratio [OR], 0.94; 95% confidence interval [CI]: 0.90-0.98; p < 0.01), male sex (OR, 2.64; 95% CI: 1.40-4.99; p < 0.01), length of surgery ≥ 180 min (OR, 2.78; 95% CI: 1.30-5.96; p < 0.01), BMI ≥ 30 kg/m² (OR, 2.89; 95% CI: 1.20-6.97; p < 0.05), and revision status (OR, 2.30; 95% CI: 1.07-4.98; p < 0.05) were independently associated with SSI postoperatively.

CONCLUSION

Lower preoperative PNI was found to be a risk factor for SSI after spine surgery. Patients with lower preoperative PNI values should be cautioned about the risk of SSI and provide adequate informed consent.

Postdischarge antibiotic use for prophylaxis following spinal fusion

OBJECTIVE

Despite recommendations to discontinue prophylactic antibiotics after incision closure or <24 hours after surgery, prophylactic antibiotics are continued after discharge by some clinicians. The objective of this study was to determine the prevalence and factors associated with postdischarge prophylactic antibiotic use after spinal fusion.

DESIGN

Multicenter retrospective cohort study.

PATIENTS

This study included patients aged ≥18 years undergoing spinal fusion or refusion between July 2011 and June 2015 at 3 sites. Patients with an infection during the surgical admission were excluded.

METHODS

Prophylactic antibiotics were identified at discharge. Factors associated with postdischarge prophylactic antibiotic use were identified using hierarchical generalized linear models.

RESULTS

In total, 8,652 spinal fusion admissions were included. Antibiotics were prescribed at discharge in 289 admissions (3.3%). The most commonly prescribed antibiotics were trimethoprim/sulfamethoxazole (22.1%), cephalexin (18.8%), and ciprofloxacin (17.1%). Adjusted for study site, significant factors associated with prophylactic discharge antibiotics included American Society of Anesthesiologists (ASA) class ≥3 (odds ratio [OR], 1.31; 95% CI, 1.00-1.70), lymphoma (OR, 2.57; 95% CI, 1.11-5.98), solid tumor (OR, 3.63; 95% CI, 1.62-8.14), morbid obesity (OR, 1.64; 95% CI, 1.09-2.47), paralysis (OR, 2.38; 95% CI, 1.30-4.37), hematoma/seroma (OR, 2.93; 95% CI, 1.17-7.33), thoracic surgery (OR, 1.39; 95% CI, 1.01-1.93), longer length of stay, and intraoperative antibiotics.

CONCLUSIONS

Postdischarge prophylactic antibiotics were uncommon after spinal fusion. Patient and perioperative factors were associated with continuation of prophylactic antibiotics after hospital discharge.

Intervention to reduce the incidence of surgical site infection in spine surgery

BACKGROUND

This study examines the incidence, characteristics, and risk factors of surgical site infections (SSIs) after spine surgery and evaluates the efficacy of a preventive intervention.

METHODS

This was a quasi-experimental pretest/posttest study in patients undergoing spinal surgery in an orthopedic surgery department from December 2014 to November 2016. Based on the results of the study, we revised the preventive protocol with modification of wound dressing, staff training, and feedback. SSI rates were compared between the pre-intervention (December 2014 to November 2015) and post-intervention (December 2015 to November 2016) periods. The risk factors were analyzed using univariate and multivariate analyses.

RESULTS

Of the 139 patients included, 14 cases of SSI were diagnosed, with a significant decrease in the incidence of SSIs from the pre-intervention period to the post-intervention period (19.4% vs 2.6%; P = .001). The etiology was known in 13 cases, with enteric flora being predominant in the pre-intervention group. Univariate analysis showed that age, body mass index, days until sitting and ambulation, and incontinence were statistically significant risk factors. After multivariate analysis, only body mass index and days until ambulation remained significant. When the effect of intervention was adjusted with other risk factors, this variable remained statistically significant.

CONCLUSIONS

An intervention that includes modification of wound dressing and early mobilization, as well as staff awareness training, monitoring, and feedback, allowed a significant reduction in the incidence of SSI following spinal surgery, particularly infections caused by enteric flora.

The Effect of Prolonged Postoperative Antibiotic Administration on the Rate of Infection in Patients Undergoing Posterior Spinal Surgery Requiring a Closed-Suction Drain: A Randomized Controlled Trial

BACKGROUND

Closed-suction drains are frequently used following posterior spinal surgery. The optimal timing of antibiotic discontinuation in this population may influence infection risk, but there is a paucity of evidence. The aim of this study was to determine whether postoperative antibiotic administration for 72 hours (24 hours after drain removal as drains were removed on the second postoperative day) decreases the incidence of surgical site infection compared with postoperative antibiotic administration for 24 hours.

METHODS

Patients undergoing posterior thoracolumbar spinal surgery managed with a closed-suction drain were prospectively randomized into 1 of 2 groups of postoperative antibiotic durations: (1) 24 hours, or (2) 24 hours after drain removal (72 hours). Drains were discontinued on the second postoperative day. The duration of antibiotic administration was not blinded. All subjects received a single dose of preoperative antibiotics, as well as intraoperative antibiotics if the surgical procedure lasted >4 hours. The primary outcome was the rate of complicated surgical site infection (deep or organ or space) within 1 year of the surgical procedure.

RESULTS

The trial was terminated at an interim analysis, when 552 patients were enrolled, for futility with respect to the primary outcome. In this study, 282 patients were randomized to postoperative antibiotics for 24 hours and 270 patients were randomized to postoperative antibiotics for 72 hours. A complicated infection developed in 17 patients (6.0%) in the 24-hour group and in 14 patients (5.2%) in the 72-hour group (p = 0.714). The superficial infection rate did not differ between the groups (p = 0.654): 9.6% in the 24-hour group compared with 8.1% in the 72-hour group. Patients in the 72-hour group had a median hospital stay that was 1 day longer (p < 0.001). At 1 year, patient-rated outcomes including leg and back pain and physical and mental functioning were not different between the groups.

CONCLUSIONS

The extension of postoperative antibiotics for 72 hours, when a closed-suction drain is required, was not associated with a reduction in the rate of complicated surgical site infection after posterior thoracolumbar spinal surgery.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of Levels of Evidence.

Preoperative Narcotic Use, Impaired Ambulation Status, and Increased Intraoperative Blood Loss Are Independent Risk Factors for Complications Following Posterior Cervical Laminectomy and Fusion Surgery

OBJECTIVE

This retrospective cohort study seeks to identify risk factors associated with complications following posterior cervical laminectomy and fusion (PCLF) surgery.

METHODS

Adults undergoing PCLF from 2012 through 2018 at a single center were identified. Demographic and radiographic data, surgical characteristics, and complication rates were compared. Multivariate logistic regression models identified independent predictors of complications following surgery.

RESULTS

A total of 196 patients met the inclusion criteria and were included in the study. The medical, surgical, and overall complication rates were 10.2%, 23.0%, and 29.1% respectively. Risk factors associated with medical complications in multivariate analysis included impaired ambulation status (odds ratio [OR], 2.27; p=0.02) and estimated blood loss over 500 mL (OR, 3.67; p=0.02). Multivariate analysis revealed preoperative narcotic use (OR, 2.43; p=0.02) and operative time (OR, 1.005; p=0.03) as risk factors for surgical complication, whereas antidepressant use was a protective factor (OR, 0.21; p=0.01). Overall complication was associated with preoperative narcotic use (OR, 1.97; p=0.04) and higher intraoperative blood loss (OR, 1.0007; p=0.03).

CONCLUSION

Preoperative narcotic use and estimated blood loss predicted the incidence of complications following PCLF for CSM. Ambulation status was a significant predictor of the development of a medical complication specifically. These results may help surgeons in counseling patients who may be at increased risk of complication following surgery.

Persistent Postoperative Hyperglycemia as a Risk Factor for Operative Treatment of Deep Wound Infection After Spine Surgery

BACKGROUND

Surgical site infections (SSIs) affect 1% to 9% of all spine surgeries. Though previous work has found diabetes mellitus type 2 (DM2) to increase the risk for wound infection, the influence of perioperative hyperglycemia is poorly described.

OBJECTIVE

To investigate perioperative hyperglycemia as an independent risk factor for surgical site infection.

METHODS

We retrospectively identified patients undergoing operative management of SSIs occurring after spinal surgery for degenerative pathologies. These patients were individually matched to controls based upon age, surgical invasiveness, ICD-10CM, race, and sex. Cases and controls were compared regarding medical comorbidities (including diabetes), postoperative hyperglycemia, and operative time.

RESULTS

Patients in the infection group were found to have a higher BMI (33.7 vs 28.8), higher prevalence of DM2 (48.5% vs 14.7%), and longer inpatient stay (8.8 vs 4.3 d). They also had higher average (136.6 vs 119.6 mg/dL) and peak glucose levels (191.9 vs 153.1 mg/dL), as well as greater variability in glucose levels (92.1 vs 58.1 mg/dL). Multivariable logistic regression identified BMI (odds ratio [OR] = 1.13), diabetes mellitus (OR = 2.12), average glucose on the first postoperative day (OR = 1.24), peak postoperative glucose (OR = 1.31), and maximal daily glucose variation (OR = 1.32) as being significant independent predictors of postoperative surgical site infection.

CONCLUSION

Postoperative hyperglycemia and poor postoperative glucose control are independent risk factors for surgical site infection following surgery for degenerative spine disease. These data suggest that, particularly among high-risk diabetic patients, strict perioperative glucose control may decrease the risk of SSI.

Preoperative measures to prevent/minimize risk of surgical site infection in spinal surgery

Background:

Multiple measures prior to spine surgery may reduce the risks of postoperative surgical site infections (SSIs).

Methods:

The incidence of SSI following spinal surgery (including reoperations and readmissions) may be markedly reduced by performing less extensive procedures and avoiding fusion where feasible. Preoperative testing up to 3 weeks postoperatively should include other studies to limit the perioperative SSI risk; cardiac stress tests (e.g., older patients/cardiac comorbidities), starting tamsulosin in males over 60 (e.g. avoid urinary retention due to benign prostatic hypertrophy), albumin/prealbumin levels (e.g., low levels increase SSI risk), and HBA1C levels to identify new/treat known diabetics (normalize/reduce preoperative levels).

Results:

Other measures include the timely administration of preoperative antibiotics (e.g., cefazolin 2 g nonpenicillin allergic), one dose of gentamicin (adjusted dose/weight), nasal cultures for methicillin-resistant Staphylococcus aureus (patients/health-care workers), and bathing 2 weeks preoperatively with chlorhexidine gluconate 4% (not just night before/morning of surgery). Additionally, prior to surgery, the following medications that increase the bleeding risk should be stopped (e.g. for varying periods); anticoagulants, antiplatelet therapies (e.g., aspirin for at least 7–10 days), nonsteroidal anti-inflammatories (NSAIDS: timing depends on the drug), vitamin E, and herbal supplements. Additionally, avoiding elective spinal surgery in morbidly obese patients and recognizing other major medical contraindications to spinal surgery should help reduce infection, morbidity, and mortality rates.

Conclusions:

Appropriate preoperative and intraoperative prophylactic maneuvers may reduce the risk of postoperative spinal SSI. Specific attention to these details may avoid infections and improve outcomes.