Surgical Wound Misclassification: A Multicenter Evaluation

Preoperative Prediction of Postoperative Infections Using Machine Learning and Electronic Health Record Data

OBJECTIVE

To estimate preoperative risk of postoperative infections using structured electronic health record (EHR) data.

BACKGROUND

Surveillance and reporting of postoperative infections is primarily done through costly, labor-intensive manual chart reviews on a small sample of patients. Automated methods using statistical models applied to postoperative EHR data have shown promise to augment manual review as they can cover all operations in a timely manner. However, there are no specific models for risk-adjusting infectious complication rates using EHR data.

METHODS

Preoperative EHR data from 30,639 patients (2013-2019) were linked to the American College of Surgeons National Surgical Quality Improvement Program preoperative data and postoperative infection outcomes data from 5 hospitals in the University of Colorado Health System. EHR data included diagnoses, procedures, operative variables, patient characteristics, and medications. Lasso and the knockoff filter were used to perform controlled variable selection. Outcomes included surgical site infection, urinary tract infection, sepsis/septic shock, and pneumonia up to 30 days postoperatively.

RESULTS

Among >15,000 candidate predictors, 7 were chosen for the surgical site infection model and 6 for each of the urinary tract infection, sepsis, and pneumonia models. Important variables included preoperative presence of the specific outcome, wound classification, comorbidities, and American Society of Anesthesiologists physical status classification. The area under the receiver operating characteristic curve for each model ranged from 0.73 to 0.89.

CONCLUSIONS

Parsimonious preoperative models for predicting postoperative infection risk using EHR data were developed and showed comparable performance to existing American College of Surgeons National Surgical Quality Improvement Program risk models that use manual chart review. These models can be used to estimate risk-adjusted postoperative infection rates applied to large volumes of EHR data in a timely manner.

A Spanish Survey on the Perioperative Use of Antimicrobials in Small Animals

Appropriate use of perioperative antimicrobials can significantly reduce the risk of post-operative infections. However, inappropriate antimicrobial use can result in the creation of multidrug-resistant bacteria, increased costs, host flora disruption, side effects and increased risk of hospital-acquired infections. This survey evaluated the current perioperative use of antimicrobials in small animals by Spanish veterinarians using a web-based questionnaire. Responses were represented using descriptive statistics and a statistical analysis of the association between demographic data and perioperative antimicrobial use was performed. Pre-operative antimicrobials were administered in clean surgery by up to 68.3% of participants, 81.0% in clean-contaminated surgery and 71.3% in dirty surgery, while in the post-operative period, antimicrobials were administered by up to 86.3% of participants in clean surgery, 93.2% in clean-contaminated surgery and 87.5% in dirty surgery. Factors considered "very important" for antimicrobial selection were the degree of wound contamination, patient immunosuppression and use of prosthesis. The most frequently used antimicrobial was beta-lactamase-resistant (or potentiated) penicillin. Post-operative antimicrobial use was associated with participants without specific surgical postgraduate training. This study highlights an overuse of antimicrobials in perioperative procedures in small animal surgery in Spain. Therefore, evidence-based guidelines and further education regarding the correct use of antimicrobial prophylaxis are recommended.

Reoperation following urgent and emergent colectomy in the State of Michigan

BACKGROUND

Reoperation is associated with unfavorable outcomes and increased healthcare utilization. This study seeks to investigate the incidence and factors related to reoperation in patients undergoing urgent/emergent colectomies.

METHODS

The Michigan Surgical Quality Collaborative (MSQC) database was used to identify patients undergoing urgent/emergent colectomies. Outcomes and risk factors of patients who underwent reoperation within 30 days were compared to those who did not.

RESULTS

16,004 patients undergoing urgent/emergent colon resection were identified. Reoperation occurred in 12.4% and was associated with increased 30-day mortality (16.7% vs. 9.6%, p < .0001), median hospital length of stay (17 vs. 10 days, p < .0001), readmission rate (21.0% vs. 12.1%, p < .001), and discharge to a location other than home (62.3% vs. 36.8%, p < .0001). Reoperation rate was highest for vascular-related indications (23.5%), and was associated with several clinical factors (male gender, low albumin, ASA classification, and presence of pre-operative sepsis, dialysis or ventilator dependence) CONCLUSIONS: Reoperation following urgent/emergent colectomy occurs frequently. Additional study into strategies to reduce reoperations in this population is warranted.

A Comparison of Interobserver Reliability Between Orthopedic Surgeons Using the Centers for Disease Control Surgical Wound Class Definitions

BACKGROUND

The Centers for Disease Control (CDC) created a classification to help stratify surgical wounds based on contamination and risk of developing a surgical site infection. The classification includes four options (I to IV) depending on the level of contamination present. Although universally applied to a variety of surgical specialties, it is unknown whether the current system is reliable when considering orthopaedic surgeries. The purpose of this study was to compare the degree of interobserver reliability between orthopaedic surgeons using the current CDC wound class definitions.

METHODS

A questionnaire containing 30 clinical vignettes was completed by 39 orthopaedic surgeons at our institution. After each vignette, respondents were asked to determine the appropriate wound class based on information provided in the vignette. The overall interobserver agreement among all participants was analyzed. In addition, respondents were queried about the adequacy of the current classification system in describing orthopaedic surgical wound class.

RESULTS

Interobserver agreement was poor at 66%, with a coefficient of concordance of 0.48. Only six physicians (15.4%) thought that the current wound classification system adequately covered orthopaedic surgery.

CONCLUSIONS

There is poor interobserver reliability using the CDC surgical wound class definitions for orthopaedic surgeries. Alternate definitions are needed to improve the validity of the system for subspecialty procedures.

Wound Classification Score Discordance in Pediatric Operations - A Quality Improvement Study

BACKGROUND

Wound classification scores are used to categorize the risk of postoperative infections. It was noted at our academic institution that wound classifications were often inaccurately recorded in the electronic health record. We thus instituted a quality improvement program, hypothesizing that this would improve charting accuracy.

METHODS

On June 1, 2019, we posted the wound classifications in each pediatric operating room (OR), provided OR nurses with teaching, and began including the classification in the postoperative surgeon debriefing. We performed a retrospective chart review of all general pediatric operations from June 19 to December 19 to compare classifications recorded in the electronic health record to the "correct" classification determined by manual review of operating reports. These data were compared with a similar chart review from 2018. To compare the efficacy of nursing versus physician focused changes, we compared our appendectomy data with a nearby community institution where the same group of surgeons practice. Pearson's Chi-squared test was used to report the significance of the differences observed in the concordance proportion, with 95% confidence intervals calculated using the Clopper-Pearson procedure.

RESULTS

Overall, 444 pre- and 179 postpractice change charts were reviewed. There were no significant differences pre or postpractice change. At the community institution, we noted a significant improvement in charting accuracy for appendectomies from 3.33% to 44.83%.

DISCUSSION

Despite implementing nursing and physician focused quality improvement practices, there was not a significant improvement in charting accuracy at the academic institution. However, we did note an improvement at the community facility where our pediatric surgeons also practice. We thus suspect that our nursing focused changes may have been inadequate. Future efforts will focus on providing intensive and sustained OR nurse training to help improve the wound classification charting accuracy.

Risk of peri-operative complications in children receiving preoperative steroids

BACKGROUND

Steroid use predisposes adult patients to increased perioperative complications including wound dehiscence and delayed wound healing. A similar large study investigating the perioperative impact of steroid use in pediatric patients has not been performed.

METHODS

The National Surgical Quality Improvement Project Pediatric Database was queried from 2012-2017 to identify patients who received steroid preoperatively. Patient demographics, comorbidities, surgical variables, and outcomes were compared between cohorts. Patients were propensity score matched and thirty-day adverse events were compared.

RESULTS

Of 425,251 pediatric surgery patients, 9716 (2.3%) received preoperative steroids. Pediatric patients treated with steroids were older and had more comorbidities. After propensity score matching, the steroid population had a significantly higher rate of adverse events, including prolonged hospital stay (15.3% vs. 9.1%, p < 0.001), seizure (0.9% vs. 0.4%, p < 0.001), readmission (14.4% vs. 9.2%, p < 0.001), and death (2.2% vs. 1.1%, p < 0.001).

CONCLUSION

Preoperative steroid use is independently associated with increased 30-day postoperative adverse events among pediatric patients. Given the significant impact of steroid use on surgical outcomes, the risks and benefits of steroid treatment in children receiving surgery should be carefully evaluated.

Actionable Risk Model for the Development of Surgical Site Infection after Emergency Surgery

Background: Surgical site infections (SSIs) increase mortality and the economic burden associated with emergency surgery (ES). A reliable and sensitive scoring system to predict SSIs can help guide clinician assessment and patient counseling of post-operative SSI risk. We hypothesized that after quantifying the ES post-operative SSI incidence, readily abstractable parameters can be used to develop an actionable risk stratification scheme. Patients and Methods: We reviewed retrospectively all patients who underwent ES operations at an urban academic hospital system (2005-2013). Comorbidities and operative characteristics were abstracted from the electronic health record (EHR) with a primary outcome of post-operative SSIs. Risk of SSI was calculated using logistic regression modeling and validated using bootstrapping techniques. Beta-coefficients were calculated to correlate risk. A simplified clinical risk assessment tool was derived by assigning point values to the rounded β-coefficients. Results: A total of 4,783 patients with a 13.2% incidence of post-operative SSIs were identified. The strongest risk factors associated with SSIs included acute intestinal ischemia, weight loss, intestinal perforation, trauma-related laparotomy, radiation exposure, previous gastrointestinal surgery, and peritonitis. The assessment tool defined three patient groups based on SSI risk. Post-operative SSI incidence in high-risk patients (34%; score = 6-10) exceeded that of medium- (11.1%; score = 3-5) and low-risk patients (1.5%; score = 1-2) (C statistic = 0.802). Patients with a risk score ≥10 points evidenced the highest post-operative SSI risk (71.9%). Conclusion: Pre-operative identification of ES patient risk for post-operative SSI may inform pre-operative patient counseling and operative planning if the proposed procedure includes medical device implantation. A clinically relevant seven-factor risk stratification model such as this empirically derived one may be suitable to incorporate into the EHR as a decision-support tool.

Clinical feasibility and safety of third space robotic and endoscopic cooperative surgery for gastric gastrointestinal stromal tumors dissection : A new surgical technique for treating gastric GISTs

Background

Surgical management of gastric gastrointestinal stromal tumors (GISTs) has evolved towards minimal invasiveness. Laparoscopic wedge resection and laparoscopic and endoscopic cooperative surgery had been considered as standard surgical treatments for gastric GISTs > 2 cm. However, stomach deformation and the full-thickness gastric defect caused by these procedures may increase the risk of morbidity. To address these problems, we developed a novel technique, third space robotic and endoscopic cooperative surgery (TS-RECS), which could dissect the tumor entirely while preserving the intact mucosal layer. Here we performed a prospective evaluation of the feasibility and safety of TS-RECS.

Methods

Patients with gastric GISTs were recruited between April 2018 and April 2019. During the operation, the gastric GIST was located by endoscopic view firstly and the submucosal injection was performed. The tumor was then dissected through robotic surgery. Clinicopathological characteristics, operative data, adverse events, and follow-ups were prospectively collected and analyzed.

Results

A total of 20 patients with gastric GISTs received TS-RECS. The mean tumor size was 33.0 ± 7.3 mm. R0 resection was achieved in all patients with a median operation time of 115 min and a median blood loss of 20 ml. The integrity of mucosal layer was maintained in 95% (19/20) of the patients. All patients started oral diet on postoperative day 1 or 2, staying in the hospital for a median of 6 days after surgery. There were no major adverse events. Local or distant recurrences were not observed during a median follow-up period of 10 months.

Conclusions

Our study suggests that TS-RECS appears to be a feasible and safe technique which could be an alternative method for resecting gastric GISTs > 2 cm.

Clinical Trials

ClinicalTrials.gov NCT03804762.

Electronic supplementary material

The online version of this article (10.1007/s00464-019-07223-w) contains supplementary material, which is available to authorized users.

Surgical Wound Misclassification to Clean From Clean-Contaminated in Common Abdominal Operations

BACKGROUND

Wound classification helps predict wound-related complications and is useful in stratifying surgical site infection reporting. We sought to evaluate misclassification among commonly performed surgeries that are at least clean-contaminated.

MATERIALS AND METHODS

The National Surgical Quality Improvement Program database was queried from 2005 to 2016 by Current Procedural Terminology codes identifying common surgeries that are, by definition, not clean: colectomy, cholecystectomy, hysterectomy, and appendectomy. Univariate analysis and multivariate logistic regression were performed.

RESULTS

Of the 1,208,544 operative cases reviewed, 22,925 (1.90%) were misclassified as clean. Hysterectomy was the most commonly misclassified operation (3.11%), and colectomy the least (0.82%). Misclassification was higher in laparoscopic cases (1.92% versus 1.82%; P < 0.01). Misclassification increased from 2005 to 2016 (0.22% versus 3.11%; P < 0.01). Misclassified patients were younger (46.7 versus 47.7 y; P < 0.01); had lower rates of hypertension, chronic obstructive pulmonary disease, smoking history, and steroid use (P < 0.01); and had shorter length of stay (2.2 versus 3.2 d; P < 0.01), lower 30-d readmission rates (3.7% versus 5.0%; P < 0.01), and less surgical site infections (1.7% versus 3.4%; P < 0.01). Open hysterectomy was the most significant positive predictor for misclassification (odds ratio 3.34; P < 0.01). Open appendectomy was the most significant negative predictor (odds ratio 0.20; P < 0.01).

CONCLUSIONS

There is an increasing trend of misclassifying wounds as clean. Misclassified patients have better outcomes, and misclassification may be affected by patient characteristics, operative approach, and type of procedure rather than reflecting the true infectious burden. Further research is warranted.

Protective effect of intraoperative re-dose of prophylactic antibiotics on surgical site infection in diabetic patients: a retrospective cohort study

Background

Surgical site infection (SSI) has a high incidence in diabetic surgical patients. Preoperative antibiotic prophylaxis followed by an intraoperative re-dose was a common strategy in diabetic prolonged procedures. However, there were lacking studies on the relative benefits of this strategy on SSI. Our study aimed to clarify the effect of intraoperative re-dose of prophylactic antibiotics on SSI in diabetic patients.

Methods

A total of 1,840 diabetic patients with prolonged surgeries were included and Cefazolin was the only type of antibiotic prophylaxis. We assessed the relationship between intraoperative re-dose of cefazolin and 30-day incidence of SSI using a retrospective cohort study method.

Results

There were 361 diabetic cases with preoperative antibiotics only and 1,479 cases with pre- plus intraoperative antibiotics, in which 60 subjects suffered from SSI. Pre- plus intraoperative prophylaxis group had a lower rate of SSI in the overall and subgroup analyses when compared with preoperative only group. Operation location, combined with hypertension, poor blood glucose control, high WBC count and ASA score >2 were significantly associated with an increased risk of SSI for diabetic surgical patients (all P<0.05). Intraoperative re-dose of prophylactic antibiotics was statistically related to a lower incidence rate of SSI than preoperative prophylaxis alone (crude RR =0.47; 95% CI, 0.27-0.82; P<0.01), while the association remained significant even after adjusting the potential confounders (adjusted RR =0.51; 95% CI, 0.29-0.90; P=0.02).

Conclusions

For diabetic patients, intraoperative re-dose of prophylactic antibiotics may be an independent protective factor for the prevention of SSI. A specific perioperative antibiotics injection strategy should be encouraged for diabetic patients with prolonged surgeries to minimize the possibility of SSI.

Operating room staff and surgeon documentation curriculum improves wound classification accuracy

BACKGROUND

Misclassification of wounds in the operating room (OR) can adversely affect surgical site infection (SSI) reporting and reimbursement. This study aimed to measure the effects of a curriculum on documentation of surgical wound classification (SWC) for operating room staff and surgeons.

METHODS

Accuracy of SWC was determined by comparing SWC documented by OR staff during the original operation to SWC determined by in-depth chart review. Patients 18 years or older undergoing inpatient surgical procedures were included. Two plan-do-act-study (PDSA) cycles were implemented over the course of 9 months. A total of 747 charts were reviewed. Accuracy of SWC documentation was retrospectively assessed across 248 randomly selected surgeries during a 5-week period prior to interventions and compared to 244 cases and 255 cases of post-intervention data from PDSA1 and PDSA2, respectively. Changes in SWC accuracy were assessed pre- and post-intervention using the kappa coefficient. A p-value for change in agreement was computed by comparing pre- and post-intervention kappa.

RESULTS

Inaccurate documentation of surgical wound class decreased significantly following curriculum implementation (kappa improved from 0.553 to 0.739 and 0.757; p = 0.001). Classification accuracy improved across all wound classes; however, class III and IV wounds were more frequently misclassified than class I and II wounds, both before and after the intervention.

CONCLUSION

Implementation of a multidisciplinary documentation curriculum resulted in a significant decrease in SWC documentation error. Improved accuracy of SWC reporting may facilitate a better assessment of SSI risk in a complex patient population.

Skin Wound Healing: Refractory Wounds and Novel Solutions

This overview of the current state of skin wound healing includes in vitro and in vivo approaches along with some recent clinical trials. From an introduction to wound healing, to tissue engineering as applied to the skin, we cover the basis for the current wound care techniques as well as novel and promising approaches. Special emphasis is given to refractory wounds which include wounds in diabetic patients. Natural compounds have been ever present in wound healing, and so we devote a section to highlighting current attempts to understand their mechanisms and to use them in novel ways.

Surgical Wound Classification and Surgical Site Infections in the Orthopaedic Patient

INTRODUCTION

The Centers for Disease Control and Prevention created a surgical wound classification system (SWC: I, clean; II, clean/contaminated; III, contaminated; and IV, dirty) to preemptively identify patients at risk of surgical site infection (SSI). The validity of this system is yet to be demonstrated in orthopaedic surgery. We hypothesize a poor association between the SWC and the rate of subsequent SSI in orthopaedic trauma cases.

METHODS

Nine hundred fifty-six orthopaedic cases were reviewed. Wounds were risk stratified intraoperatively using the SWC grades (I-IV). SSI was diagnosed clinically or with objective markers. The SWC was compared with SSI rates using a Fisher exact test. Significance was set at P < 0.05.

RESULTS

Four hundred patients met the selection criteria. The rate of infection was not significantly different across the SWC grades (P = 0.270). There was a significantly higher risk of SSI among patients with diabetes (P = 0.028).

CONCLUSIONS

The Centers for Disease Control and Prevention SWC showed poor utility in predicting and risk stratifying postoperative SSIs in orthopaedic surgical cases.

Patients at High-Risk for Surgical Site Infection

BACKGROUND

Surgical site infections (SSIs) are a significant healthcare quality issue, resulting in increased morbidity, disability, length of stay, resource utilization, and costs. Identification of high-risk patients may improve pre-operative counseling, inform resource utilization, and allow modifications in peri-operative management to optimize outcomes.

METHODS

Review of the pertinent English-language literature.

RESULTS

High-risk surgical patients may be identified on the basis of individual risk factors or combinations of factors. In particular, statistical models and risk calculators may be useful in predicting infectious risks, both in general and for SSIs. These models differ in the number of variables; inclusion of pre-operative, intra-operative, or post-operative variables; ease of calculation; and specificity for particular procedures. Furthermore, the models differ in their accuracy in stratifying risk. Biomarkers may be a promising way to identify patients at high risk of infectious complications.

CONCLUSIONS

Although multiple strategies exist for identifying surgical patients at high risk for SSIs, no one strategy is superior for all patients. Further efforts are necessary to determine if risk stratification in combination with risk modification can reduce SSIs in these patient populations.

Clinical relevance and effect of surgical wound classification in appendicitis: Retrospective evaluation of wound classification discrepancies between surgeons, Swissnoso-trained infection control nurse, and histology as well as surgical site infection rates by wound class

BACKGROUND

Surgical wound classification (SWC) is used for risk stratification of surgical site infection (SSI) and serves as the basis for measuring quality of care. The objective was to examine the accuracy and reliability of SWC. This study was purposed to evaluate the discrepancies in SWC as assessed by three groups: surgeons, an infection control nurse, and histopathologic evaluation. The secondary aim was to compare the risk-stratified SSI rates using the different SWC methods for 30 d postoperatively.

METHODS

An analysis was performed of the appendectomies from January 2013 to June 2014 in the Cantonal Hospital of Schaffhausen. SWC was assigned by the operating surgeon at the end of the procedure and retrospectively reviewed by a Swissnoso-trained infection control nurse after reading the operative and pathology report. The level of agreement among the three different SWC assessment groups was determined using kappa statistic. SSI rates were analyzed using a chi-square test.

RESULTS

In 246 evaluated cases, the kappa scores for interrater reliability among the SWC assessments across the three groups ranged from 0.05 to 0.2 signifying slight agreement between the groups. SSIs were more frequently associated with trained infection control nurse-assigned SWC than with surgeons based SWC.

CONCLUSIONS

Our study demonstrated a considerable discordance in the SWC assessments performed by the three groups. Unfortunately, the currently practiced SWC system suffers from ambiguity in definition and/or implementation of these definitions is not clearly stated. This lack of reliability is problematic and may lead to inappropriate comparisons within and between hospitals and surgeons.

Utilization of the NSQIP-Pediatric Database in Development and Validation of a New Predictive Model of Pediatric Postoperative Wound Complications

BACKGROUND

Surgical wound classification, introduced in 1964, stratifies the risk of surgical site infection (SSI) based on a clinical estimate of the inoculum of bacteria encountered during the procedure. Recent literature has questioned the accuracy of predicting SSI risk based on wound classification. We hypothesized that a more specific model founded on specific patient and perioperative factors would more accurately predict the risk of SSI.

STUDY DESIGN

Using all observations from the 2012 to 2014 pediatric National Surgical Quality Improvement Program-Pediatric (NSQIP-P) Participant Use File, patients were randomized into model creation and model validation datasets. Potential perioperative predictive factors were assessed with univariate analysis for each of 4 outcomes: wound dehiscence, superficial wound infection, deep wound infection, and organ space infection. A multiple logistic regression model with a step-wise backwards elimination was performed. A receiver operating characteristic curve with c-statistic was generated to assess the model discrimination for each outcome.

RESULTS

A total of 183,233 patients were included. All perioperative NSQIP factors were evaluated for clinical pertinence. Of the original 43 perioperative predictive factors selected, 6 to 9 predictors for each outcome were significantly associated with postoperative SSI. The predictive accuracy level of our model compared favorably with the traditional wound classification in each outcome of interest.

CONCLUSIONS

The proposed model from NSQIP-P demonstrated a significantly improved predictive ability for postoperative SSIs than the current wound classification system. This model will allow providers to more effectively counsel families and patients of these risks, and more accurately reflect true risks for individual surgical patients to hospitals and payers.

A call for a standardized definition of perforated appendicitis

BACKGROUND

Abscess rates have been reported to be as low as 1% and as high as 50% following perforated appendicitis (PA). This range may be because of lack of universal definition for PA. An evidence-based definition (EBD) is crucial for accurate wound classification, risk-stratification, and subsequent process optimization. ACS NSQIP-Pediatric guidelines do not specify a definition of PA. We hypothesize that reported postoperative abscess rates underrepresent true incidence, as they may include low-risk cases in final calculations.

METHODS

Local institutional records of PA patients were reviewed to calculate the postoperative abscess rate. The ACS NSQIP-Pediatric participant use file (PUF) was used to determine cross-institutional postoperative abscess rates. A PubMed literature review was performed to identify trials reporting PA abscess rates, and definitions and rates were recorded.

RESULTS

20.9% of our patients with PA developed a postoperative abscess. The ACS NSQIP-Pediatric abscess rate was significantly lower (7.61%, p<0.001). In the eighteen published studies analyzed, average abscess rate (14.49%) was significantly higher than ACS NSQIP-Pediatric (p<0.001). There was significantly more variation in trials that do not employ an EBD of perforation (Levene's test F-value =6.980, p=0.018).

CONCLUSIONS

A standard EBD of perforation leads to lower variability in reported postoperative abscess rates following PA. Nonstandard definitions may be significantly altering the aggregate rate of postoperative abscess formation. We advocate for adoption of a standard definition by all institutions participating in ACS NSQIP-Pediatric data submission.

LEVEL OF EVIDENCE

III.

Operative wound classification: an inaccurate measure of pediatric surgical morbidity

BACKGROUND

Wound classification has catapulted to the forefront of surgical literature and quality care discussions. However, it has not been validated in laparoscopy or children. We analyzed pediatric infection rates based on wound classification and reviewed the most common noninfectious complications which could be a more appropriate measure for quality assessment.

METHODS

We performed a retrospective review of 800 patients from 2011 to 2014 undergoing common procedures at a tertiary pediatric hospital. Demographics, procedure, wound classification and complications were analyzed using descriptive statistics.

RESULTS

Infection rates were in the expected low range for clean procedures. However, 5% of pyloromyotomy patients required readmission and 10% of circumcision patients developed penile adhesions; 2% required reoperation. Ostomy reversal, a clean contaminated case, had 17% wound infections, whereas acute appendicitis, a contaminated case had only a 4% infection rate. Laparoscopic cholecystectomy (clean-contaminated or contaminated depending on inflammation) had 2% postoperative infections. Perforated appendicitis, a dirty procedure had an 18% infection rate, below the expected >27% for dirty cases in adults.

CONCLUSIONS

Current wound classifications do not accurately approximate the risk of surgical site infections in children, particularly for laparoscopic procedures. It would be more appropriate to grade hospitals based on disease and procedure specific complications.

Surgical site infections in the NICU

BACKGROUND

Surgical site infections (SSI) increase morbidity and mortality. In adult and pediatric populations, the incidence ranges from 1.5-12%. Studies in neonates have shown an association between preoperative stay in an intensive care unit and development of SSI. To date, there has only been a single study looking exclusively at SSI in the Neonatal Intensive Care Unit (NICU). Additionally, there has been a suggestion that prematurity may be a risk factor for SSI, but this has come from studies looking at all neonates less than 28days, rather than only neonates hospitalized in a NICU.

OBJECTIVE

Primary outcome variable was to calculate the incidence of SSI in a NICU population. Secondary outcome variables were to determine if SSI is more common in premature infants and to identify additional risk factors for the development of SSI.

METHODS

An IRB-approved retrospective chart review of all patients undergoing surgical procedures in a level IIIC NICU over a 2-year period was used. We utilized the CDC's definitions of surgical procedures and SSI. An epidemiologist reviewed charts if the diagnosis of SSI was questionable. Statistical analysis was done with t test and Fisher's exact test.

RESULTS

We identified 165 patients who underwent 264 surgical procedures. Incidence of SSI was 11.7%. There were 31 SSI that occurred in 29 neonates over the 2-year period, with no mortality in that group. In patients who developed an SSI, 34.5% occurred after the 1st procedure, 41.4% occurred after a 2nd procedure, and 24.1% occurred after the 3rd or later procedure. There was no difference in perioperative antibiotic usage.

CONCLUSIONS

This study describes SSI in a strictly neonatal population in a large academic NICU. Prematurity does not appear to be a risk factor for SSI. SSI is more common in neonates who have undergone an abdominal procedure or multiple procedures. Perioperative antibiotics are not significantly associated with prevention of SSI.

Wound classification in pediatric surgical procedures: Measured and found wanting

PURPOSE

Surgical wound classification has emerged as a measure of surgical quality of care, but scant data exist in the era of minimally invasive procedures, especially in children. The aim of this study is to examine the surgical site infection (SSI) rate by wound classification during common pediatric surgical procedures.

METHODS

A retrospective analysis of the 2013 Pediatric-National Surgical Quality Improvement Program (Peds-NSQIP) dataset was conducted. Patients undergoing pyloromyotomy, cholecystectomy, ostomy reversal, and appendectomy were included. Wound classification, SSI rate, reoperation, and readmission were analyzed.

RESULTS

A total of 10,424 records were included. Pyloromyotomy, a clean case, had a 0.7% SSI rate, while ostomy reversal, a clean contaminated case, had an SSI in 6.9% of cases. Appendectomy for nonperforated acute appendicitis and laparoscopic cholecystectomy for cholecystitis, both contaminated cases, had SSI rates of 2.1% and <1%, respectively. Appendectomy for perforated appendicitis, a dirty procedure, had a 9.1% SSI rate, below the expected >40% for dirty cases. Reoperations and readmission rates ranged from <1% to 9% and increased with case complexity.

CONCLUSION

Current wound classifications systems do not reflect surgical risk in children and remain questionable tools for benchmarking surgical care in children. Role of readmissions and reoperations as quality of care indices needs further investigation.

A multicenter, pediatric quality improvement initiative improves surgical wound class assignment, but is it enough?

BACKGROUND/PURPOSE

Surgical wound classification (SWC) is widely utilized for surgical site infection (SSI) risk stratification and hospital comparisons. We previously demonstrated that nearly half of common pediatric operations are incorrectly classified in eleven hospitals. We aimed to improve multicenter, intraoperative SWC assignment through targeted quality improvement (QI) interventions.

METHODS

A before-and-after study from 2011-2014 at eleven children's hospitals was conducted. The SWC recorded in the hospital's intraoperative record (hospital-based SWC) was compared to the SWC assigned by a surgeon reviewer utilizing a standardized algorithm. Study centers independently performed QI interventions. Agreement between the hospital-based and surgeon SWC was analyzed with Cohen's weighted kappa and chi square.

RESULTS

Surgeons reviewed 2034 cases from 2011 (Period 1) and 1998 cases from 2013 (Period 2). Overall SWC agreement improved from 56% to 76% (p<0.01) and weighted kappa from 0.45 (95% CI 0.42-0.48) to 0.73 (95% CI 0.70-0.75). Median (range) improvement per institution was 23% (7-35%). A dose-response-like pattern was found between the number of interventions implemented and the amount of improvement in SWC agreement at each institution.

CONCLUSIONS

Intraoperative SWC assignment significantly improved after resource-intensive, multifaceted interventions. However, inaccurate wound classification still commonly occurred. SWC used in SSI risk-stratification models for hospital comparisons should be carefully evaluated.

Pediatric surgeon-directed wound classification improves accuracy

BACKGROUND

Surgical wound classification (SWC) communicates the degree of contamination in the surgical field and is used to stratify risk of surgical site infection and compare outcomes among centers. We hypothesized that by changing from nurse-directed to surgeon-directed SWC during a structured operative debrief, we will improve accuracy of documentation.

METHODS

An institutional review board-approved retrospective chart review was performed. Two time periods were defined: initially, SWC was determined and recorded by the circulating nurse (before debrief, June 2012-May 2013) and allowing 6 mo for adoption and education, we implemented a structured operative debriefing including surgeon-directed SWC (after debrief, January 2014-August 2014). Accuracy of SWC was determined for four commonly performed pediatric general surgery operations: inguinal hernia repair (clean), gastrostomy ± Nissen fundoplication (clean contaminated), appendectomy without perforation (contaminated), and appendectomy with perforation (dirty).

RESULTS

One hundred eighty-three cases before debrief and 142 cases after debrief met inclusion criteria. No differences between time periods were noted in regard to patient demographics, ASA class, or case mix. Accuracy of wound classification improved before debrief (42% versus 58.5%, P = 0.003). Before debrief, 26.8% of cases were overestimated or underestimated by more than one wound class, versus 3.5% of cases after debrief (P < 0.001). Interestingly, most after debrief contaminated cases were incorrectly classified as clean contaminated.

CONCLUSIONS

Implementation of a structured operative debrief including surgeon-directed SWC improves the percentage of correctly classified wounds and decreases the degree of inaccuracy in incorrectly classified cases. However, after implementation of the debriefing, we still observed a 41.5% rate of incorrect documentation, most notably in contaminated cases, indicating further education and process improvement is needed.

Implementation of the World Health Organization checklist and debriefing improves accuracy of surgical wound class documentation

BACKGROUND

Surgical wound classification (SWC) is a component of surgical site infection risk stratification. Studies have demonstrated that SWC is often incorrectly documented. This study examines the accuracy of SWC after implementation of a multifaceted plan targeted at accurate documentation.

METHODS

A reviewer examined operative notes of 8 pediatric operations and determined SWC for each case. This SWC was compared with nurse-documented SWC. Percent agreement pre- and postintervention was compared. Analysis was performed using chi-square and a P value less than .05 was significant.

RESULTS

Preintervention concordance was 58% (112/191) and postintervention was 83% (163/199, P = .001). Appendectomy accuracy was 28% and increased to 80% (P = .0005). Fundoplication accuracy increased from 44% to 84% (P = .016) and gastrostomy tube from 56% to 100% (P = .0002). The most accurate operation preintervention was pyloromyotomy and postintervention was gastrostomy tube and inguinal hernia. The least accurate pre- and postintervention was cholecystectomy.

CONCLUSION

Implementation of a multifaceted approach improved accuracy of documented SWC.

Mesh herniorrhaphy with simultaneous colorectal surgery: a case-matched study from the American College of Surgeons National Surgical Quality Improvement Program

BACKGROUND

The aim of this study is to evaluate the impact of concurrent mesh herniorrhaphy on short-term outcomes of colorectal surgery by using a large, nationwide database.

METHODS

Patients who underwent simultaneous ventral hernia repair (VHR) and colorectal surgery between 2005 and 2010 were identified from the American College of Surgeons National Surgical Quality Improvement Program. Patients who underwent VHR with mesh repair were case matched with patients who underwent VHR without mesh based on the type of colorectal procedure, diagnosis, and American Society of Anesthesiologists score.

RESULTS

Two hundred sixty-two patients who underwent VHR with mesh were case matched with 524 patients who underwent VHR without mesh. Mean operating time was significantly longer in patients who underwent VHR with mesh (195.8 ± 98.7 vs 164.3 ± 84.4 minutes, P < .001). Postoperative morbidity (P = .58), mortality (P = .27), superficial surgical site infection (SSI) (P = .14), deep SSI (P = .38), organ space SSI (P = .17), wound disruption (P > .99), reoperation (P = .48), and length of hospital stay (P = .71) were comparable between the groups.

CONCLUSION

The American College of Surgeons National Surgical Quality Improvement Program data suggest that VHR with mesh does not increase 30-day mortality, medical or surgical morbidity in colorectal surgery setting.

Development and validation of a risk stratification score for ventral incisional hernia after abdominal surgery: hernia expectation rates in intra-abdominal surgery (the HERNIA Project)

BACKGROUND

Ventral incisional hernias (VIH) develop in up to 20% of patients after abdominal surgery. No widely applicable preoperative risk-assessment tool exists. We aimed to develop and validate a risk-assessment tool to predict VIH after abdominal surgery.

STUDY DESIGN

A prospective study of all patients undergoing abdominal surgery was conducted at a single institution from 2008 to 2010. Variables were defined in accordance with the National Surgical Quality Improvement Project, and VIH was determined through clinical and radiographic evaluation. A multivariate Cox proportional hazard model was built from a development cohort (2008 to 2009) to identify predictors of VIH. The HERNIAscore was created by converting the hazards ratios (HR) to points. The predictive accuracy was assessed on the validation cohort (2010) using a receiver operator characteristic curve and calculating the area under the curve (AUC).

RESULTS

Of 625 patients followed for a median of 41 months (range 0.3 to 64 months), 93 (13.9%) developed a VIH. The training cohort (n = 428, VIH = 70, 16.4%) identified 4 independent predictors: laparotomy (HR 4.77, 95% CI 2.61 to 8.70) or hand-assisted laparoscopy (HAL, HR 4.00, 95% CI 2.08 to 7.70), COPD (HR 2.35; 95% CI 1.44 to 3.83), and BMI ≥ 25 kg/m(2) (HR1.74; 95% CI 1.04 to 2.91). Factors that were not predictive included age, sex, American Society of Anesthesiologists (ASA) score, albumin, immunosuppression, previous surgery, and suture material or technique. The predictive score had an AUC = 0.77 (95% CI 0.68 to 0.86) using the validation cohort (n = 197, VIH = 23, 11.6%). Using the HERNIAscore: HERNIAscore = 4(∗)Laparotomy+3(∗)HAL+1(∗)COPD+1(∗) BMI ≥ 25, 3 classes stratified the risk of VIH: class I (0 to 3 points),5.2%; class II (4 to 5 points),19.6%; and class III (6 points), 55.0%.

CONCLUSIONS

The HERNIAscore accurately identifies patients at increased risk for VIH. Although external validation is needed, this provides a starting point to counsel patients and guide clinical decisions. Increasing the use of laparoscopy, weight-loss programs, community smoking prevention programs, and incisional reinforcement may help reduce rates of VIH.