The Rationale for Developing Scoring Systems for Clinical Practice

Predicting Mortality Following Odontoid Fracture Fixation in Elderly Patients: CAADS-16 Score

STUDY DESIGN

Retrospective Review of a National Database.

INTRODUCTION

By utilizing a national database, this study aims to quantify the predictors of 30-day mortality after odontoid fixation and guide appropriate management for patients in whom the choice between operative and non-operative management is unclear.

METHODS

The American College of Surgeons National Surgical Quality Improvement Database was queried using Current Procedural Terminology (CPT) codes and International Classification of Disease (ICD) codes to identify patients 60 or older who underwent surgical fixation of an odontoid fracture from 2005 to 2020. Risk factors for mortality significant in univariate and subsequent multivariate analysis were used to develop a scoring system to predict post-operative mortality.

RESULTS

608 patients were identified. Patients were split into a non-mortality 30 days post-op group, and into a mortality 30 days post-op group. The following risk factors were included in the scoring system: functional dependency, disseminated cancer, albumin less than 3.5, WBC count greater than 16 k, anterior surgical approach, and pre-op SIRS. Using a cutoff value of 2, the CAAD-16 score had a sensitivity and specificity of 82% and 81%, respectively. The ASA score, cutoff at 4, showed a sensitivity and specificity of 64% and 75% respectively.

CONCLUSIONS

This sample of 294 patients represents one of the largest samples of odontoid fracture fixation patients available in the literature and comes from a nationally representative database. We structure relevant risk factors into the CAADS-16 score, which has the potential to be a clinically relevant tool to prevent short-term postoperative mortality.

Practical Risk Scoring System for Predicting Severity of COVID-19 Disease

OBJECTIVES

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19 disease, has become an international pandemic with numerous casualties. It had been noted that the severity of the COVID-19 disease course depends on several clinical, laboratory, and radiological factors. This has led to risk scoring systems in various populations such as in China, but similar risk scoring systems based on the American veteran population are sparse, particularly with the vulnerable Veteran population. As a simple risk scoring system would be very useful, we propose a simple Jhala Risk Scoring System (JRSS) to assess the severity of disease risk.

METHODS

A retrospective review of all SARS-CoV-2 reverse transcriptase-polymerase chain reaction (RT-PCR) tests collected and performed at the regional Veterans Administration Medical Center (VAMC) serving the Philadelphia and surrounding areas from March 17th, 2020 to May 20th, 2020. Data was collected and analyzed in the same year. These tests were reviewed within the computerized medical record system for demographic, medical history, laboratory test history, and clinical course. Information from the medical records were then scored based on the criteria of the Jhala Risk Scoring System (JRSS).

RESULTS

The JRSS, based on age, ethnicity, presence of any lung disease, presence of cardiovascular disease, smoking history, and diabetes history with laboratory parameters correlated and predicted (with statistical significance) which patients would be hospitalized.

CONCLUSION

The JRSS may play a role in informing which COVID-19 positive patients in the emergency room/urgent care for risk stratification.

The CARDE-B Scoring System Predicts 30-Day Mortality After Revision Total Joint Arthroplasty

BACKGROUND

There exists a substantial risk of having a perioperative complication after revision total joint arthroplasty (TJA). The complex shared decision-making between surgeon and patient would benefit from a high-fidelity tool to identify patients at risk for mortality after revision TJA. Therefore, we developed the CARDE-B score. CARDE-B is an acronym for congestive heart failure, albumin or malnutrition (<3.5 mg/dL), renal failure on dialysis, dependence for daily living, elderly (>65 years of age), and body mass index <25 kg/m2. We developed and validated the CARDE-B score to determine the risk of death within 30 days of a revision TJA.

METHODS

A total of 13,118 revision TJAs (40% hip and 60% knee) from the National Surgical Quality Improvement Program (NSQIP) database were analyzed. A simple 1-point scoring system, CARDE-B, was created for predicting 30-day mortality after revision TJA, based on a logistic regression model. The CARDE-B scoring system assigns 1 point to each criterion in the acronym: congestive heart failure, albumin (<3.5 mg/dL), renal failure on dialysis, dependence for daily living, elderly (>65 years of age), and body mass index of <25 kg/m2. The CARDE-B scoring system was compared with 2 commonly utilized scores: American Society of Anesthesiologists (ASA) physical status classification and the 5-factor modified frailty index (mFI-5). The area under the curve (AUC) was used to assess the accuracy of each model. The Hosmer-Lemeshow test was used to assess goodness of fit. Finally, the Nationwide Inpatient Sample (NIS) was used for external validation of the CARDE-B score in 19,153 patients who underwent revision TJA in 2017.

RESULTS

Eighty-eight patients (0.7%) did not survive 30 days after revision TJA. The AUC for the logistic regression model was 0.88 in both the derivation and internal validation samples using NSQIP. The predicted probability of 30-day mortality after revision TJA increased stepwise from <0.01% for a CARDE-B score of 0 points to 39% for a CARDE-B score of 5 points. The AUC for the CARDE-B score predicting 30-day mortality after revision TJA was 0.85. This was more accurate (p < 0.001) than the ASA physical status classification (AUC, 0.77) and the mFI-5 (AUC, 0.67). The AUC for the CARDE-B score in the NIS external validation set was 0.75. The Hosmer-Lemeshow p value for goodness of fit was 0.34, indicating goodness of fit in the external validation sample.

CONCLUSIONS

The CARDE-B score is a simple system that predicts the risk of death within 30 days of a revision TJA, offering surgeons and patients a valuable and validated risk-stratification tool.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Clinical and Microbiologic Characteristics of Clostridium difficile Infection Caused by Binary Toxin Producing Strain in Korea

BACKGROUND

Binary toxin-producing Clostridium difficile infections (CDI) are known to be more severe and to cause higher case fatality rates than those by binary toxin-negative isolates. There has been few data of binary toxin-producing CDI in Korea. Objective of the study is to characterize clinical and microbiological trait of CDI cause by binary-toxin producing isolates in Korea.

MATERIALS AND METHODS

From September 2008 through January 2010, clinical characteristics, medication history and treatment outcome of all the CDI patients were collected prospectively. Toxin characterization, PCR ribotyping and antibiotic susceptibility were performed with the stool isolates of C. difficile.

RESULTS

During the period, CDI caused by 11binary toxin-producing isolates and 105 toxin A & toxin B-positive binary toxin-negative isolates were identified. Comparing the disease severity and clinical findings between two groups, leukocytosis and mucoid stool were more frequently observed in patients with binary toxin-positive isolates (OR: 5.2, 95% CI: 1.1 to 25.4, P = 0.043; OR: 7.6, 95% CI: 1.6 to 35.6, P = 0.010, respectively), but clinical outcome of 2 groups did not show any difference. For the risk factors for acquisition of binary toxin-positive isolates, previous use of glycopeptides was the significant risk factor (OR: 6.2, 95% CI: 1.4 to 28.6, P = 0.019), but use of probiotics worked as an inhibitory factor (OR: 0.1, 95% CI: 0.0 to 0.8; P = 0.026). PCR ribotypes of binary toxinproducing C. difficile showed variable patterns: ribotype 130, 4 isolates; 027, 3 isolates; 267 and 122, 1 each isolate and unidentified C1, 2 isolates. All 11 binary toxin-positive isolates were highly susceptible to clindamycin, moxifloxacin, metronidazole, vancomycin and piperacillin-tazobactam, however, 1 of 11 of the isolates was resistant to rifaximin.

CONCLUSIONS

Binary toxin-producing C. difficile infection was not common in Korea and those isolates showed diverse PCR ribotypes with high susceptibility to antimicrobial agents. Glycopeptide use was a risk factor for CDI by those isolates.

Estimating lung resection risk: a pilot study of trainee and practicing surgeons

BACKGROUND

Most surgeons believe that experience-based risk estimates for major lung resection are reliable. Elements that influence such estimates are poorly understood.

METHODS

Clinical vignettes were created for patients who underwent lung resection; 48 patients who had major complications were matched to 48 patients without complications. Ten senior surgical trainees and 9 practicing thoracic surgeons blinded to outcomes estimated the risk of complications using a seven-point scale (uninformed estimates). After review of a calculated risk score, risk was again estimated (informed estimates).

RESULTS

Risk estimates did not differentiate between patient groups with and without complications (4.8 versus 4.9; p=0.94 for trainees; 4.5 versus 4.2; p=0.21 for practicing surgeons). The accuracy of predicting complications was only fair, but was better for practicing surgeons than for trainees (58% versus 51%; p=0.041). Risk estimates correlated moderately well with baseline pulmonary function and possibly with age, but not with performance status or extent of resection. Knowledge of a calculated risk score resulted in more frequent alterations of trainee risk scores, improved interobserver agreement in both groups, and aligned trainee and practicing surgeon estimates more closely.

CONCLUSIONS

Surgeon estimates are not accurate in predicting lung resection complications using vignette-based, matched-pair methodology. Practicing surgeons and trainees base risk estimates on limited objective clinical data. Trainee estimates are more susceptible to modification by a standard risk score than are estimates of practicing surgeons. Prospective studies are necessary to further explore the etiology, accuracy, and utility of surgeon risk estimates.

Risk modelling of outcome after general and trauma surgery (the IRIS score)

Background

A practical, easy to use model was developed to stratify risk groups in surgical patients: the Identification of Risk In Surgical patients (IRIS) score.

Methods

Over 15 years an extensive database was constructed in a general surgery unit, containing all patients who underwent general or trauma surgery. A logistic regression model was developed to predict mortality. This model was simplified to the IRIS score to enhance practicality. Receiver operating characteristic (ROC) curve analysis was performed.

Results

The database contained a consecutive series of 33 224 patients undergoing surgery. Logistic regression analysis gave the following formula for the probability of mortality: P (mortality) = A/(1 + A), where A = exp (−4·58 + (0·26× acute admission) + (0·63× acute operation) + (0·044× age) + (0·34× severity of surgery)). The area under the ROC curve (AUC) was 0·92. The IRIS score also included age (divided into quartiles, 0–3 points), acute admission, acute operation and grade of surgery. The AUC predicting postoperative mortality was 0·90.

Conclusion

The IRIS score accurately predicted mortality after general or trauma surgery.

Clinical characteristics and risk factors of colistin-induced nephrotoxicity

Since multidrug-resistant gram-negative organisms have been increasing, polymyxin E (colistin) has been reintroduced despite its nephrotoxicity. A case-control study was performed to investigate the incidence, clinical characteristics and risk factors of colistin-induced nephrotoxicity. From August 2006 to June 2008, 47 cases receiving at least one defined daily dose (DDD) of intravenous colistin were included; 15 (31.9%) of the 47 cases developed nephrotoxicity with preserved urine output, 3 (20%) of whom underwent renal replacement therapy. The mean dosage of colistimethate sodium was 2.25 g (22.5 DDD; range 0.6-8.7 g) at the time of nephrotoxicity. Of 10 patients who were re-assessed for renal function after 1 month, 9 (90%) recovered their renal function. In the univariate analysis, site of infection, hypoalbuminaemia and cumulative dosage of the second-generation fluoroquinolones, aminoglycosides and non-steroidal anti-inflammatory drugs (NSAIDs) co-administered during colistin treatment as well as concomitant use of NSAIDs were risk factors for nephrotoxicity. However, in the logistic regression hypoalbuminaemia and the use of NSAIDs were significant risk factors for increased nephrotoxicity during colistin administration, suggesting that free colistin might cause renal toxicity. In conclusion, colistin-induced nephrotoxicity occurred at a high rate, and hypoalbuminaemia and concomitant use of NSAIDs were significant risk factors.