Association of Obesity With Septic Complications After Major Abdominal Surgery: A Secondary Analysis of the RELIEF Randomized Clinical Trial

Phase angle is a predictor for postoperative complications in colorectal cancer

Aim

The aim of this study was to develop a validated nomogram to predict the risk of postoperative complications in colorectal cancer (CRC) patients by analyzing the factors that contribute to these complications.

Methods

We retrospectively collected clinical information on patients who underwent CRC surgery at a single clinical center from January 2021 to December 2021. Univariate and multivariate logistic regression analysis to identify independent risk factors for postoperative complications and to develop a predictive model. A receiver operating characteristic (ROC) curve was used to calculate the area under the curve (AUC) to assess the predicted probability. Calibration curve was drawn to compare the predicted probability of the nomogram with the actual probability, and decision curve analysis (DCA) was employed to evaluate the clinical utility of the nomogram.

Results

A total of 190 CRC patients were included in this study. We retrospectively collected baseline information, clinical information, surgical information, and nutrition-related indicators for all patients. Through multivariate logistic regression analysis, preoperative albumin (p = 0.041, OR = 0.906, 95% CI = 0.824-0.996), surgical time (p = 0.009, OR = 1.006, 95% CI = 1.001-1.010), waistline (p = 0.049, OR = 1.011, 95% CI = 1.002-1.020) and phase angle (PA) (p = 0.022, OR = 0.615, 95% CI = 0.405-0.933) were identified as independent risk factors for postoperative complications in CRC, and a nomogram prediction model was established using the above four variables. The AUC of 0.706 for the ROC plot and the high agreement between predicted and actual probabilities in the calibration curves suggested that the prediction model has good predictive power. The DCA also confirmed the good clinical performance of the nomogram.

Conclusion

This study developed a nomogram to predict the risk of postoperative complications in CRC patients, providing surgeons with a reliable reference to personalized patient management in the perioperative period and preoperative nutritional interventions.

Impact of Metabolic Syndrome on Post-Operative Infection in Patients Undergoing Flexible Ureteroscopy Lithotripsy

Background: To investigate retrospectively whether metabolic syndrome (MetS) of flexible ureteroscopy (fURS) lithotripsy can be used to predict post-operative infection. Patients and Methods: After screening, 1,110 patients who received fURS lithotripsy for upper urinary tract stones in our center between January 2015 and December 2022 were analyzed retrospectively. Patients were divided into MetS-positive group and MetS-negative group. Post-operative infection was divided into fever, urosepsis, and septic shock. Relevant data during the peri-operative period were collected. Univariable and multivariable logistic regression analyses were adopted to estimate the impact of metabolic syndrome on post-operative infection in patients undergoing fURS lithotripsy. Results: Among the 1,110 patients, 427 tested positive for MetS, whereas 683 tested negative. Eighty-eight patients suffered from fever (67 patients in the MetS-positive group and 21 in the MetS-negative group). Forty-nine patients had urosepsis (29 patients in the MetS-positive group and 20 in the MetS-negative group), of whom seven patients developed septic shock. No patient developed multiple organ failure or died because of infection. The prevalence of post-operative infections in the MetS-positive group was higher than that in the MetS-negative group (p < 0.001). Multivariable logistic regression analyses showed that diabetes mellitus, MetS-positive, positive urine culture, and longer operation time were positively correlated with post-operative fever. Positive MetS, positive urine culture, and longer operation time were strongly correlated with post-operative urosepsis. Conclusions: Metabolic syndrome was found to be associated with post-operative infection in patients undergoing fURS lithotripsy, suggesting it can serve as a predictive factor.

Incidence and predictors of deep incisional and organ/space surgical site infection following radical cystectomy

OBJECTIVE

To investigate clinical risk factors associated with postoperative deep incisional or organ/space surgical site infections (SSI) following radical cystectomy (RC) in a well characterized and large contemporary cohort.

METHODS

We used the American College of Surgeons National Surgical Quality Improvement Program database to identify adult patients who underwent RC for bladder cancer between 2015 and 2020 (n = 13,081). We conducted multivariable-adjusted logistic regression and Cox adjusted proportional hazards regression analysis to identify clinical predictors of deep incisional or organ/space SSI in the 30-day postoperative-period following RC.

RESULTS

Deep incisional or organ/space SSI risk increased with continent urinary diversion (HR = 1.61, 95% CI: 1.38-1.88; P < 0.001), obesity (HR = 1.60, 95% CI: 1.35-1.90; P < 0.001), diabetes mellitus (HR = 1.30, 95% CI: 1.13-1.51; P < 0.001), and being functionally dependent before surgery (HR = 2.09, 95% CI: 1.44-3.03; P < 0.001).

CONCLUSIONS

Postoperative deep incisional or organ/space SSIs following RC occur more frequently in patients who were obese, diabetic, functionally dependent before surgery, and those who underwent continent urinary diversion. These findings may assist urologists in preoperative counseling, medical optimization, and choice of urinary diversion approach, as well as improved patient monitoring and identification of candidates for intervention postoperatively.

[Surgical site infection and perioperative antibiotics in dermatosurgery]

BACKGROUND

Postoperative wound infections represent the most common complication in dermatosurgery. Given the low incidence and heterogeneous data, no standards for perioperative antibiotic prophylaxis (PAP) have been established in clinical practice.

OBJECTIVES

To summarize the current evidence on risk factors for postoperative wound infection in dermatosurgery and the new recommendations on PAP.

MATERIALS AND METHODS

Relevant study data and current recommendations were summarized descriptively.

RESULTS

Current evidence suggests that the following factors are associated with an increased risk of wound infection after dermatosurgical procedures: surgery to the lower extremity or the ear, postoperative hemorrhage, defect closure by flap or skin graft, large wound defect, immunosuppression, and male sex. Probably not affecting the risk of infection are diabetes, obesity, age, smoking, use of a blood thinner, multiple surgeries, or wound healing by second intention. Not all risk factors affect the risk of infection equally. They must be weighted differently and only in combination do they increase the risk of wound infection in a clinically relevant way. According to a current position paper of the German Society for Dermatosurgery, the indication for PAP should be made individually and only if multiple factors are present. Furthermore, patients with increased risk for bacterial endocarditis or hematogenic endoprosthesis infection should receive PAP prior to septic skin surgery.

CONCLUSION

In dermatologic surgery, PAP should be restricted to patients at high risk for wound infection. Further indications are the prevention of bacterial endocarditis and hematogenic endoprosthesis infection in high-risk individuals prior to septic surgery.

Perioperative antibiotic prophylaxis in skin surgery - Position paper of the Antibiotic Stewardship working group of the German Society for Dermatologic Surgery (DGDC), Part 1: Procedure- and patient-related risk factors

The aim of perioperative antibiotic prophylaxis (PAP) is to prevent the occurrence of surgical site infections (SSIs) or other infectious complications (especially bacterial endocarditis or septic arthritis). PAP is effective in surgeries where overall infection rates are high even without considering patient-related risk factors (such as orthopedic surgery or fracture repair). Surgery on airways, gastrointestinal, genital, or urinary tract is also considered to be associated with a risk of infection and may require PAP. Overall, SSIs in skin surgery are relatively rare and vary between 1% and 11% depending on the localization, complexity of the wound closure and patient cohort. Therefore, the general surgical recommendations regarding PAP only partially reflect the needs of dermatologic surgery. In contrast to the USA, where recommendations on the use of PAP in skin surgery already exist, there are currently no guidelines for the use of PAP specifically designed for dermatologic surgery in Germany. In the absence of an evidence-based recommendation, the use of PAP is guided by the experience of the surgeons and leads to a heterogeneous use of antimicrobial substances. In this work, we summarize the current scientific literature on the use of PAP and make a recommendation depending on procedure- and patient-related risk factors.

Perioperative Antibiotikaprophylaxe in der Dermatochirurgie - Positionspapier der Arbeitsgruppe Antibiotic Stewardship der Deutschen Gesellschaft für Dermatochirurgie (DGDC), Teil 1: Eingriffs- und patientenbezogene Risikofaktoren

Die perioperative Antibiotikaprophylaxe (PAP) hat das Ziel, postoperative Wundinfektionen und Infektionskomplikationen (insbesondere bakterielle Endokarditis oder septische Arthritis) bei chirurgischen Eingriffen zu vermeiden. Die PAP hat sich besonders bei Eingriffen bewährt, bei denen die Infektionsraten auch ohne Berücksichtigung der patientenbezogenen Risikofaktoren insgesamt hoch sind (wie für orthopädische Eingriffe oder die Versorgung von Frakturen). Auch Operationen mit Eröffnung der Atemwege, des Verdauungs‐, Genital‐ oder Harntrakts gelten als mit Infektionsrisiko behaftet und können eine PAP erfordern. In der Dermatochirurgie sind Infektionskomplikationen insgesamt verhältnismäßig selten und variieren in Abhängigkeit von der Lokalisation, Komplexität des Eingriffes und der Patientenkohorte zwischen 1% und 11%. Daher spiegeln die allgemeinchirurgischen Empfehlungen bezüglich der PAP die Bedürfnisse der Dermatochirurgie nur begrenzt wider. Im Gegensatz zu den USA, wo eine entsprechende Empfehlung vorliegt, existiert in Deutschland zurzeit keine speziell für dermatochirurgische Eingriffe konzipierte Leitlinie zur Anwendung von PAP. In Abwesenheit evidenzbasierter Empfehlungen wird die PAP durch die Erfahrung der einzelnen Operateure geprägt, was zu einer heterogenen Anwendung antimikrobieller Substanzen führt. In der vorliegenden Arbeit wird die aktuelle wissenschaftliche Literatur zu dem Thema zusammengefasst und die daraus resultierende Empfehlung zur Anwendung der PAP in Abhängigkeit von eingriffs‐ und patientenbezogenen Risikofaktoren formuliert.

Obesity Is Associated With Increased Risk for Adverse Postoperative Outcomes After Distal Pancreatectomy for Pancreatic Ductal Adenocarcinoma

INTRODUCTION

Conflicting reports exist about the effect obesity has on adverse postoperative surgical outcomes after distal pancreatectomy (DP). The aim of this study is to explore the role of obesity in terms of morbidity and pancreas-specific complications following DP for pancreatic ductal adenocarcinoma (PDAC).

METHODS

All patients who underwent DP at a single institution over 10 y were analyzed (2009-2020). Patients were categorized as nonobese (body mass index [BMI] < 30 kg/m2) and obese (BMI ≥ 30 kg/m2). Independent predictors of adverse postoperative outcomes were calculated using multivariate logistic regression models. Overall survival was assessed using Kaplan-Meier survival analysis.

RESULTS

Of the 178 patients included, 58 (32.5%) were obese. Clinically relevant postoperative pancreatic fistula (CR-POPF) formation rate was significantly higher in the obese group (20.6% versus 7.5%, P value = 0.011). We did not identify any significant difference between obese and nonobese patients in median overall survival (30.2 mon versus 28.9 mon, P value = 0.811). On multivariate binary logistic regression analysis, BMI ≥ 30 was an independent predictor of morbidity (any complication) and CR-POPF formation after DP for PDAC.

CONCLUSIONS

Obesity is associated with a significantly increased risk for CR-POPF in patients undergoing DP for PDAC. Obesity should be considered as a variable in fistula risk calculators for DP.

Obesity and mid-term outcomes following robotic cholecystectomy

BACKGROUND

As obese adults often suffer from gallbladder disease, more data on postoperative outcomes following robotic cholecystectomy(RC) is needed.

METHODS

RC candidates with a body mass index(BMI) > 30 kg/m² were included. Postoperative course was documented and analyzed. A logistic regression analysis was performed to determine possible risk factors associated with complications.

RESULTS

617 patients with a BMI of 35.9 ± 6.4 kg/m² were included of which 65 had complicated gallbladders (gangrenous, fistulated, or abscessed). Eight cases were converted to open. Sixty-five(10.5%) patients revisited the emergency department within 30 days, and 35(5.7%) were readmitted to the hospital. Average follow-up time was 35 months. Fifty(9.1%) patients experienced complications, eight(1.5%) underwent reoperation. Postoperative complications were associated with chronic obstructive pulmonary disease[p < 0.001, Odds-Ratio(OR):8.418, 95%-Confidence-interval(CI):4.029-17.585], BMI(p < 0.024, OR:1.045, 95%-CI:[1.006-1.086]), class-III obesity (p < 0.021, OR:2.221, 95%-CI:[1.126-4.379], and complicated gallbladders (p < 0.001, OR:3.659, 95%CI:[1.665-8.041]).

CONCLUSION

This is the first study to establish a link between higher obesity classes and postoperative complications following RC.

Sepsis and postoperative surgical site infections

Surgical site infections remain a significant cause of morbidity and mortality. High-quality evidence supports several measures to prevent surgical site infections that should be applied with high compliance, although effective application remains suboptimal. Recognizing high-risk patients and avoiding potential pitfalls in the diagnosis of surgical site infections is paramount in preventing progression to sepsis, particularly in emergency surgical patients with physiologic derangement. A high index of suspicion postoperatively is critical to identify patients with surgical site infections and to prevent failure to rescue.

Towards interpretable, medically grounded, EMR-based risk prediction models

Machine-learning based risk prediction models have the potential to improve patient outcomes by assessing risk more accurately than clinicians. Significant additional value lies in these models providing feedback about the factors that amplify an individual patient's risk. Identification of risk factors enables more informed decisions on interventions to mitigate or ameliorate modifiable factors. For these reasons, risk prediction models must be explainable and grounded on medical knowledge. Current machine learning-based risk prediction models are frequently 'black-box' models whose inner workings cannot be understood easily, making it difficult to define risk drivers. Since machine learning models follow patterns in the data rather than looking for medically relevant relationships, possible risk factors identified by these models do not necessarily translate into actionable insights for clinicians. Here, we use the example of risk assessment for postoperative complications to demonstrate how explainable and medically grounded risk prediction models can be developed. Pre- and postoperative risk prediction models are trained based on clinically relevant inputs extracted from electronic medical record data. We show that these models have similar predictive performance as models that incorporate a wider range of inputs and explain the models' decision-making process by visualizing how different model inputs and their values affect the models' predictions.

Systemic Complications of Obesity in Operative Acetabular Fractures

OBJECTIVE

To determine the effect of obesity on rates of systemic complications in operatively treated acetabular fractures.

DESIGN

Retrospective Case-Control study.

SETTING

Level 1 Trauma Center.

PATIENTS/PARTICIPANTS

All patients with acetabular fractures managed operatively from January 2015 to December 2019. Patients were divided into groups based on their body mass index (BMI) (normal weight = BMI <25 kg/m2, overweight = BMI 25-30, obese = BMI 30-40, and morbidly obese = BMI >40).

INTERVENTION

Operative management of an acetabular fracture.

MAIN OUTCOME MEASUREMENT

Systemic complications, including mortality, sepsis, pneumonia, acute respiratory distress syndrome, deep vein thrombosis, pulmonary embolism, or venous thrombotic event.

RESULTS

A total of 428 patients were identified. One hundred nine patients (25.4%) were in normal weight, 133 (31.1%) were overweight, 133 (31.1%) were obese, and 53 (12.4%) were morbidly obese. The rate of systemic complications was 17.5%, and overall mortality rate was 0.005%. There were no significant differences between the different BMI groups in all-cause complications or any individual complications. When the morbidly obese group was compared with all other patients, there were also no significant differences in all-cause complications or any individual complications.

CONCLUSION

In conclusion, in this study, there was no association with increasing BMI and inpatient systemic complications after operative management of acetabular fractures. As we continue to refine our understanding of how obesity affects outcomes after acetabular fracture surgery, other indices of obesity might prove more useful in predicting complications. In the obese population, there are well-documented risks of postoperative infections and challenges in obtaining an anatomic reduction, but the fear of postoperative systemic complications should not deter surgeons from undertaking operative management of acetabular fractures in the obese population. Because the prevalence of obesity in trauma patients continues to increase, it is incumbent on us to continue to improve our understanding of optimal treatment for our patients.

LEVEL OF EVIDENCE

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

Predicting recovery and disability after surgery in patients with severe obesity: The role of the six-minute walk test

The most appropriate method to predict postoperative outcomes in patients with severe obesity undergoing elective non-bariatric surgery is not known. We conducted a single-centre prospective cohort study in patients with a body mass index of at least 35 kg/m² undergoing non-bariatric, non-cardiac surgery. Patients completed the six-minute walk test prior to surgery. Disability was measured before and six months after surgery using the World Health Organization disability assessment schedule. Primary outcome measures included quality of recovery at one month and significantly increased disability at six months after surgery. A total of 293 patients participated. The median body mass index was 41 kg/m². Patients generally recovered well. Following surgery, 9% of patients experienced a poor quality of recovery and 7% developed a significant increase in disability. The proportion of patients free from clinically significant disability increased from 66% prior to surgery to 90% at six months after surgery. The distance walked in six minutes was weakly predictive of poor recovery at one month and significantly increased disability at six months; weight and body mass index were not. The area under the receiver operating characteristic curve was 0.65 (95% confidence intervals 0.51 to 0.78) for poor recovery and 0.64 (95% confidence intervals 0.51 to 0.77) for increased disability. A preoperative six-minute walk test distance of 308 m was the best cut-off value for predicting increased postoperative disability (sensitivity 0.68, specificity 0.63). The six-minute walk test was most discriminatory at shorter distances. This population of patients with severe obesity appeared to recover well and had few adverse outcomes. The degree of functional capacity was more important than the degree of obesity in predicting postoperative outcomes.

Obesity and Anterior Abdominal Gunshot Wounds: A Cushion Effect

Background

Although the standard of care for anterior abdominal gunshot wounds (AAGSWs) is immediate laparotomy, these operations are associated with a high rate of negativity and potentially serious complications. Recent data suggest the possibility of selective non-operative management (SNOM) of AAGSWs, but none implicate body mass index (BMI) as a factor in patient selection. Anecdotal experience at our trauma center suggested a protective effect of obesity among patients with AAGSWs, and given the exceptionally high rate of obesity in the Bronx, we sought to analyze the associations of AAGSWs and BMI to inform future trauma research and management. In this study, we aimed to evaluate whether BMI is associated with injury severity, resource utilization, and clinical outcomes of AAGSWs.

Methodology

From our prospectively accrued trauma registry, we retrospectively abstracted all patients greater than 16 years old with Current Procedural Terminology codes associated with gunshot wounds from 2008 to 2016. The electronic medical record was reviewed to define a cohort of patients with at least one AAGSW. Patients were divided into the following cohorts based on BMI: underweight (UW, BMI: <18.5), normal weight (NW, BMI: 18.5-24.9), overweight (OW, BMI: 25-29.9), and obese (OB, BMI: ≥30). Among these cohorts, we analyzed data regarding injury severity, resource utilization, and clinical outcomes.

Results

In this study, none of the patients were UW, 17 (42.5%) patients were NW, 15 (37.5%) patients were OW, and eight (20%) patients were OB. One patient each in the NW and OB cohorts was successfully managed non-operatively, while all others underwent immediate exploratory laparotomy. The mean new injury severity score was significantly lower as BMI increased (NW = 30.9 ± 17.0, OW = 22.9 ± 16.1, and OB = 12.8 ± 13.7; p = 0.039). Patients in the OB cohort were less likely to have abdominal fascial penetration compared to the OW and NW cohorts (p = 0.027 and 0.004, respectively) and sustained fewer mean visceral injuries compared to the OW and NW cohorts (p = 0.027 and 0.045, respectively). OB patients were significantly more likely to have sustained two or more AAGSWs (OB = 27.5%, OW = 6.7%, and NW = 5.9%; p = 0.033), suggesting higher rates of tangential soft tissue injuries. The mean hospital length of stay down-trended as BMI increased but did not achieve statistical significance (NW = 7.4 ± 5.3, OW = 6.6 ± 6.7, and OB = 3.1 ± 2.3; p = 0.19). The OB cohort had the lowest mean hospital charges.

Conclusions

Obesity may yield a protective effect among AAGSW victims, and BMI may provide trauma surgeons another tool to triage patients for SNOM of AAGSWs, potentially diminishing the risks associated with negative laparotomy. Our data serve as the basis for the analysis of a larger patient cohort.