Abdominal Wall Thickness is a Predictor for Surgical Site Infections in Patients Undergoing Colorectal Operations

Surgical Site Infections in Colorectal Cancer Surgeries: A Systematic Review and Meta-Analysis of the Impact of Surgical Approach and Associated Risk Factors

BACKGROUND

Surgical site infections (SSIs) represent a noteworthy contributor to both morbidity and mortality in the context of patients who undergo colorectal surgery. Several risk factors have been identified; however, their relative significance remains uncertain.

METHODS

We conducted a meta-analysis of observational studies from their inception up until 2023 that investigated risk factors for SSIs in colorectal surgery. A random-effects model was used to pool the data and calculate the odds ratio (OR) and 95% confidence interval (CI) for each risk factor.

RESULTS

Our analysis included 26 studies with a total of 61,426 patients. The pooled results showed that male sex (OR = 1.45), body mass index (BMI) ≥ 25 kg/m2 (OR = 1.09), American Society of Anesthesiologists (ASA) score ≥ 3 (OR = 1.69), were all independent risk factors for SSIs in colorectal surgery. Conversely, laparoscopic surgery (OR = 0.70) was found to be a protective factor.

CONCLUSIONS

The meta-analysis conducted revealed various risk factors, both modifiable and non-modifiable, associated with surgical site infections (SSIs) in colorectal surgery. These findings emphasize the significance of targeted interventions, including optimizing glycemic control, minimizing blood loss, and using laparoscopic techniques whenever feasible in order to decrease the occurrence of surgical site infections in this particular group of patients.

S110-Opioid-free analgesia after outpatient general surgery: A qualitative study focused on the perspectives of patients and clinicians involved in a pilot trial

BACKGROUND

Opioid-free analgesia (OFA) may mitigate opioid-related harms after outpatient general surgery; however, the comparative effectiveness of this approach should be assessed in robust randomized controlled trials (RCTs). Undertaking an RCT on OFA raises important practical concerns, including surgeon and patient hesitation regarding pain management without opioids. We conducted a qualitative study to explore patients' and clinicians' perspectives and experiences with a pilot trial focused on OFA after outpatient general surgery.

METHODS

Patients undergoing outpatient abdominal and breast procedures were randomized to receive post-discharge opioid analgesia (OA) or OFA. Semi-structured interviews with patients and clinicians involved in the trial were conducted to elicit personal perspectives and experiences. Purposive sampling for maximum variation was used to recruit participants with diverse characteristics. Transcribed interviews were assessed using inductive thematic analysis.

RESULTS

Ten patients (5 abdominal, 5 breast) and 10 clinicians (6 surgeons, 2 anesthesiologists, 2 nurses) were interviewed. Five major themes emerged: readiness for trial engagement, pre-trial thoughts about the interventions, postoperative pain experiences, intervention acceptability, and trial refinement. Most patients were open to OFA. Clinicians expressed willingness to prescribe OFA, particularly after less invasive procedures and when using peripheral nerve blocks (PNBs). Concerns were raised regarding the adequacy of pain control and side effects of non-opioid drugs (e.g., NSAID-induced bleeding, kidney injury). Overall, participants were enthusiastic about the trial and recognized its relevance; clinicians praised the study design and organization; and patients valued the use of electronic questionnaires. Suggestions for improvements included preventing potential bias arising from the use of PNBs (i.e., via standardization or stratification) and reducing patient burden (i.e., decreasing postoperative questionnaires).

CONCLUSION

Patients and clinicians who participated in a pilot RCT generally accept the clinical equipoise between OA versus OFA after outpatient general surgery and recognize the need for methodologically robust trials to inform evidence-based analgesia prescribing.

Quantifying the Impact of Imaging Through Body Walls on Shear Wave Elasticity Measurements

In the context of ultrasonic hepatic shear wave elasticity imaging (SWEI), measurement success has been determined to increase when using elevated acoustic output pressures. As SWEI sequences consist of two distinct operations (pushing and tracking), acquisition failures could be attributed to (i) insufficient acoustic radiation force generation resulting in inadequate shear wave amplitude and/or (ii) distorted ultrasonic tissue motion tracking. In the study described here, an opposing window experimental setup that isolated body wall effects separately between the push and track SWEI operations was implemented. A commonly employed commercial track configuration was used, harmonic multiple-track-location SWEI. The effects of imaging through body walls on the pushing and tracking operations of SWEI as a function of mechanical index (MI), spanning 5 different push beam MIs and 10 track beam MIs, were independently assessed using porcine body walls. Shear wave speed yield was found to increase with both increasing push and track MI. Although not consistent across all samples, measurements in a subset of body walls were found to be signal limited during tracking and to increase yield by up to 35% when increasing electronic signal-to-noise ratio by increasing harmonic track transmit pressure.

The Association Between Metabolic Derangement and Wound Complications in Elective Plastic Surgery

INTRODUCTION

The incidence of metabolically unhealthy obesity is rising nationally. In this study, we compare wound and overall complications between metabolically unhealthy obese and healthy patients undergoing elective plastic surgery and model how operative time influences a complication risk.

METHODS

Patients undergoing elective breast and body plastic surgery procedures in the 2009-2019 National Surgical Quality Improvement Program (NSQIP) dataset were identified. Complications were compared between metabolically unhealthy obese (body mass index [BMI] > 30 with diabetes and/or hypertension) versus metabolically healthy obese patients (BMI > 30 without diabetes or hypertension). Logistic regression was used to model the probability of wound complications across operative times stratified by metabolic status.

RESULTS

Of 139,352 patients, 13.4% (n = 18,663) had metabolically unhealthy obesity and 23.8% (n = 33,135) had metabolically healthy obesity. Compared to metabolically healthy patients, metabolically unhealthy patients had higher incidence of wound complications (6.9% versus 5.6%; P < 0.001) and adverse events (12.4% versus 9.6%; P < 0.001), in addition to higher 30-d readmission, returns to the operating room, and length of stay (all P < 0.001). After adjustment, BMI (Odds ratio [OR] 7.86), hypertension (OR 1.15), and diabetes (OR 1.25) were independent risk factors for wound complications (all P < 0.001). Among metabolically unhealthy patients, the operative time was log-linear with a wound complication risk (OR 1.21; P < 0.001).

CONCLUSIONS

Diabetes and hypertension are additive risk factors with obesity for wound complications in elective plastic surgery. Among patients with metabolically unhealthy obesity, a risk of wound complications increases logarithmically with operative time. This distinction with regard to metabolic state might explain the unclear impact of obesity on surgical outcomes within existing surgical literature.

Abdominal subcutaneous obesity and the risk of burst abdomen: a matched case-control study

PURPOSE

The causes of burst abdomen after midline laparotomy remain uncertain. Obesity is a suspected risk factor. The purpose of this study was to investigate the association between abdominal subcutaneous obesity (ASO) and burst abdomen in patients undergoing emergency midline laparotomy.

METHODS

We conducted a single-centre, retrospective, matched case-control study of patients undergoing emergency midline laparotomy from May 2016 to August 2021. Patients suffering from burst abdomen were matched 1:4 with controls based on age and sex. Abdominal wall closure was standardized in the study period with the small bites, small stitches technique. ASO was defined as the highest sex-specific quartile (≥ 75%) of subcutaneous fat layer evaluated on CT. The primary outcome was the association between ASO and burst abdomen, stratified between cases and controls. Secondary outcomes included 30- and 90-day mortality, length of stay, and suspected risk factors of burst abdomen, assessed by multivariate analysis across cases and controls.

RESULTS

A total of 475 patients were included in this study, with 95 cases matched to 380 controls. Liver cirrhosis, active smoking, and high alcohol consumption were more common among cases in an unadjusted analysis. Liver cirrhosis (odds ratio (OR) 3.32, p = 0.045) and active smoking (OR 1.98, p = 0.009) remained significant in a multivariate analysis and were associated with burst abdomen. One hundred twenty-four patients had ASO. ASO was not significantly associated with burst abdomen (OR 1.11, p = 0.731).

CONCLUSION

ASO was not found to be associated with an increased risk of burst abdomen after emergency midline laparotomy.

The radiographic soft tissue thickness is associated with wound complications after open reduction and internal fixation of patella fractures

Background

Displaced patella fracture is commonly treated with open reduction and internal fixation (ORIF). Wound complications after surgery often lead to prolonged hospitalization and dissatisfaction of patients. Periarticular adiposity and swelling may be associated with wound complications. The purpose of this study is to determine the relationship between periarticular soft tissue thickness and wound complications after ORIF of patella fractures.

Methods

We retrospectively studied 237 patients undergoing ORIF for patella fractures from June 2017 to February 2021 at our institution. We established periarticular soft tissue thickness ratio (PSTTR) to evaluate soft tissue status on lateral knee X-ray radiographs. Univariate analysis was performed to identify the association between PSTTR and postoperative wound complication. A receiver-operating characteristic (ROC) curve analysis was performed to evaluate the predictive value of PSTTR.

Results

The incidence of postoperative wound complication was 10.5%. Minor wound complication occurred in 24 patients, and major wound complication occurred in one patient. The average femoral PSTTR (fPSTTR) was 0.94 ± 0.17 and the average tibial PSTTR (tPSTTR) was 0.66 ± 0.16. fPSTTR proved to be associated with postoperative wound complication. In the ROC analysis of fPSTTR predicting postoperative wound complication, the area under curve (AUC) was 0.676, which indicated a moderate predictive value.

Conclusions

PSTTR was a feasible method to assess periarticular soft tissue. The increased fPSTTR was associated with wound complications after ORIF of patella fractures.

Reading a preoperative CT scan to guide complex abdominal wall reconstructive surgery

Computed tomography (CT) scanning is the imaging modality of choice when planning the overall management and operative approach to complex abdominal wall hernias. Despite its availability and well-recognised benefits there are no guidelines or recommendations regarding how best to read or report such scans for this application. In this paper we aim to outline an approach to interpreting preoperative CT scans in abdominal wall reconstruction (AWR). This approach breaks up the interpretive process into 4 steps-concentrating on the hernia or hernias, any complicating features of the hernia(s), the surrounding soft tissues and the abdominopelvic cavity as a whole-and was developed as a distillation of the authors' collective experience. We describe the key features that should be looked for at each of the four steps and the rationale for their inclusion.