Pediatric surgeon-directed wound classification improves accuracy

Centers for Disease Control (CDC) Wound Classification is Prognostic of 30-Day Readmission Following Surgery

BACKGROUND

The goal of this study was to investigate factors associated with 30-day readmission in a multivariate model, including the CDC wound classes "clean," "clean/contaminated," "contaminated," and "dirty/infected."

METHODS

The 2017-2020 American College of Surgeons-National Surgical Quality Improvement Program (ACS-NSQIP) database was queried for all patients undergoing total hip replacement, coronary artery bypass grafting, Ivor Lewis esophagectomy, pancreaticoduodenectomy, distal pancreatectomy, pneumonectomy, and colectomies. ACS-defined wound classes were concordant with CDC definitions. Multivariate linear mixed regression was used to determine risk factors for readmission while adjusting for type of surgery as a random intercept.

RESULTS

477,964 cases were identified, with 38,734 (8.1%) patients having experienced readmission within 30 days of surgery. There were 181,243 (37.9%) cases classified as wound class "clean", 215,729 (45.1%) cases classified as "clean/contaminated", 40,684 cases (8.5%) classified as "contaminated", and 40,308 (8.4%) cases classified as "dirty/infected". In the multivariate generalized mixed linear model adjusting for type of surgery, sex, body mass index, race, American Society of Anesthesiologists class, presence of comorbidity, length of stay, urgency of surgery, and discharge destination, "clean/contaminated" (p < .001), "contaminated" (p < .001), and "dirty/infected" (p < .001) wound classes (when compared to "clean") were significantly associated with 30-day readmission. Organ/space surgical site infection and sepsis were among the most common reasons for readmission in all wound classes.

CONCLUSIONS

Wound classification was strongly prognostic for readmission in multivariable models, suggesting that it may serve as a marker of readmissions. Surgical procedures that are "non-clean" are at significantly greater risk for 30-day readmission. Readmissions may be due to infectious complications; optimizing antibiotic use or source control to prevent readmission are areas of future study.

Surgical wound classification in otolaryngology: A state-of-the-art review

Objective

To describe the issues related to the assignment of surgical wound classification as it pertains to Otolaryngology-Head & Neck surgery, and to present a simple framework by which providers can assign wound classification.

Data Sources

Literature review.

Conclusion

Surgical wound classification in its current state is limited in its utility. It has recently been disregarded by major risk assessment models, likely due to inaccurate and inconsistent reporting by providers and operative staff. However, if data accuracy is improved, this metric may be useful to inform the risk of surgical site infection. In an era of quality-driven care and reimbursement, surgical wound classification may become an equally important indicator of quality.

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.

Surgical site infection after open and laparoscopic surgery in children: a systematic review and meta-analysis

Surgical site infections (SSIs) are the most common healthcare-associated infections in patients undergoing surgery. Various randomised control trials (RCTs) indicate that laparoscopic procedures can be associated with better outcomes compared to open procedures. However, how open versus laparoscopic approaches compare across various paediatric procedures with respect to SSI rate remains poorly defined. In this review, we examined RCTs that directly compare SSI rates after open versus laparoscopic operations for appendicitis, gastro-esophageal reflux, inguinal hernia, and pyloric stenosis. MEDLINE, Embase, and Web of Science were searched for RCTs comparing four types of open versus laparoscopic operations in children. The operations included appendectomy, fundoplication for gastro-esophageal reflux, inguinal hernia repair, or pyloromyotomy. 364 records were identified and screened, 54 full-text articles were assessed for eligibility, and 17 RCTs were included in the analysis. SSI rate was the primary outcome. Operative time and length of stay (LOS) were the secondary outcomes. A meta-analysis was conducted using RevMan 5.4 software. Laparoscopic appendectomy had a lower SSI rate than open appendectomy (odds ratio of 2.22 [1.19, 4.15] p = 0.01). Laparoscopic fundoplication for gastro-esophageal reflux, inguinal hernia repair, or pyloromyotomy for pyloric stenosis were not associated with lower SSI rate compared to open surgery. Operative time was shorter in open fundoplication (- 71.22 min [- 89.79,  - 52.65] p < 0.00001) than laparoscopic fundoplication. There was no significant difference in operative time of any of the other procedures. There was no significant difference in LOS between open and laparoscopic procedures for all types of operations analysed. Based on the findings of this review, it is recommended to utilise the laparoscopic approach over the open approach to reduce SSI risk in paediatric appendectomy.

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.

Improvement of surgical wound classification following a targeted training program at a children's hospital

BACKGROUND

Inaccurate assignment of surgical wound class (SWC) remains a challenge in perioperative documentation. The purpose of our intervention was to increase the accuracy of SWC through a targeted training program directed toward pediatric surgeons and nurses.

METHODS

A retrospective electronic medical record (EMR) chart review of 400 operations was performed according to NSQIP criteria during specified periods in 2014 and 2017, assessing SWC errors before and after a training program and posting of reference materials in operating rooms at a 165-bed children's hospital. After each operation, nurses confirmed SWC with the surgeon before recording the value in the EMR. Differences in proportions of misclassified SWC were evaluated with a chi-square test.

RESULTS

Following the educational program, misclassified SWC improved from 70/200 (35.0%) to 18/200 (9.0%), p < 0.001. Misclassified SWC for appendectomies improved from 46/95 (48.4%) to 12/108 (11.1%), p < 0.001.

CONCLUSIONS

Accurate SWC assignment in the EMR was improved by an educational program and posting of materials to aid assignment, as well as enhanced communication between surgeons and nurses at the conclusion of each operation. We present the first known attempt to list all pediatric surgery procedures according to SWC. Accurate SWC allows stratification of risks and more effective targeted interventions.

LEVEL OF EVIDENCE

Level III.

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.

Enhanced neonatal surgical site infection prediction model utilizing statistically and clinically significant variables in combination with a machine learning algorithm

BACKGROUND

Machine-learning can elucidate complex relationships/provide insight to important variables for large datasets. This study aimed to develop an accurate model to predict neonatal surgical site infections (SSI) using different statistical methods.

METHODS

The 2012-2015 National Surgical Quality Improvement Program-Pediatric for neonates was utilized for development and validations models. The primary outcome was any SSI. Models included different algorithms: full multiple logistic regression (LR), a priori clinical LR, random forest classification (RFC), and a hybrid model (combination of clinical knowledge and significant variables from RF) to maximize predictive power.

RESULTS

16,842 patients (median age 18 days, IQR 3-58) were included. 542 SSIs (4%) were identified. Agreement was observed for multiple covariates among significant variables between models. Area under the curve for each model was similar (full model 0.65, clinical model 0.67, RF 0.68, hybrid LR 0.67); however, the hybrid model utilized the fewest variables (18).

CONCLUSIONS

The hybrid model had similar predictability as other models with fewer and more clinically relevant variables. Machine-learning algorithms can identify important novel characteristics, which enhance clinical prediction models.

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.

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.