Interventions to prevent and treat sarcopenia in a surgical population: a systematic review and meta-analysis

Personalizing patient risk of a life-altering event: An application of machine learning to hemiarch surgery

OBJECTIVE

The study objective was to assess a machine learning model's ability to predict the occurrence of life-altering events in hemiarch surgery and determine contributing patient characteristics and intraoperative factors.

METHODS

In total, 602 patients who underwent hemiarch replacement at a high-volume aortic center from 2009 to 2022 were included. Patients were randomly divided into training (80%) and testing (20%) sets with various eXtreme gradient boosting candidate models constructed to predict the risk of experiencing life-altering events, including stroke, mortality, or new renal replacement therapy requirement. A total of 64 input parameters from the index hospitalization were identified, including 24 demographic characteristics as well as 8 preoperative and 32 intraoperative variables. A SHapley Additive exPlanation beeswarm plot was generated to identify and interpret the impact of individual features on the predictions of the final model.

RESULTS

A life-altering event was noted in 15% (90/602) of patients who underwent hemiarch replacement, including urgent/emergency cases and dissections. The final eXtreme Gradient Boosting model demonstrated a cross-validation accuracy of 88% on the testing set and was well calibrated as evidenced by a low Brier score of 0.12. The best performing model achieved an area under the receiver operating characteristic curve of 0.76 and an area under the precision recall curve of 0.55. The SHapley Additive exPlanation beeswarm plot provided insights into key features that significantly influenced model prediction.

CONCLUSIONS

Machine learning demonstrated superior accuracy in predicting hemiarch patients who would experience a life-altering event. This model may help to guide patients and clinicians in stratifying risk on an individual basis, which may in turn influence clinical decision-making.

Combination of Parenteral Amino Acid Infusion and Intermittent Loading Exercise Ameliorates Progression of Postoperative Sarcopenia in Rat Model

Postoperative sarcopenia is associated with poor outcomes in hospitalized patients. However, few studies have focused on short-term postoperative sarcopenia. Furthermore, the influence of nutritional management using amino acids (AAs) comprising a peripheral parenteral nutrition (PPN) solution and its combination with exercise (Exc) is unclear. Hence, we established a postoperative sarcopenic rat model to evaluate the effects of parenteral AA infusion combined with Exc on skeletal muscles and investigate the underlying mechanisms involved in the amelioration of muscle atrophy. Male F344 rats underwent surgery followed by hindlimb suspension (HS) for 5 days. The rats were divided into AA (-), AA (+), AA (-)-Exc, and AA (+)-Exc groups. They were continuously administered a PPN solution with or without AA at 98 kcal/kg/day. The Exc groups were subjected to intermittent loading for 1 h per day. Postoperative sarcopenic rats exhibited decreased muscle strength and mass and an upregulated ubiquitin-proteasome system, autophagy-lysosome system, and fast-twitch fiber-related genes, especially in the AA (-) group. The AA (+)-Exc group exhibited attenuated decreased muscle strength, increased gastrocnemius mass, and a suppressed upregulation of muscle atrophy- and fast-twitch fiber-related genes. Therefore, parenteral AA infusion combined with Exc may be effective in preventing postoperative sarcopenia in hospitalized patients.

Sarcopenia and its effects on outcome of lumbar spine surgeries

PURPOSE

Sarcopenia, defined as progressive impairment of muscle function secondary to loss of skeletal muscle mass, has prevalence of 24-56% in patients > 60 years. Forty-four per cent of elderly patients undergoing orthopaedic surgery are found to be sarcopenic. It is a known risk factor for fall, fractures, disability, increased post-operative morbidity and mortality. If diagnosed pre-operatively, it can help prepare the patient and surgical team to foresee complications and thereby reduce morbidity and mortality. In the present study, we evaluated and correlated sarcopenia with the surgical outcome of operated patients with lumbar spine pathology.

MATERIALS AND METHODS

A prospective, observational study was conducted on 114 patients > 40 years undergoing lumbar spine surgeries, who were studied and followed up for 3 months. They were segregated into 5 groups based on age (40-50 year, 50-60 year, 60-70 year, 70-80 year, and  > 80 year) and were assessed separately. Data on demography, grip strength analysis, 30-s chair stand test, Psoas muscle index (calculated on pre-operative MRI), pre- and post-operative ODI (Oswestry Disability Index) scores at 2 weeks and 3 months, Dindo-Clavien Classification of peri-operative complications, 90-day readmission rates and mortality (if any) were included. Patients were segregated into sarcopenic and non-sarcopenic groups based on the definition and set parameters as per the European Working Group on Sarcopenia in Older People (EWGSOP). A comparative analysis between these groups was performed.

RESULTS

Of 114 patients, there were 18 patients in 40-49 years, 24 in 50-59 years, 33 in 60-69 years, 30 in 70-79 years and 9 in > 80 years age group. Statistically significant difference in peri-operative ODI scores was seen in sarcopenic vs non-sarcopenic patients in all age groups (p < 0.05) except 40-49 years. The results showed that sarcopenic group had higher rate of peri-operative complications, delayed mobilisation, longer stay and mortality compared to non-sarcopenic group.

CONCLUSION

We conclude that sarcopenic patients have poor outcome in lumbar spine surgery compared to those without. So, by diagnosing sarcopenia using tests routinely done as pre-operative requirement, one can reduce radiation exposure and cost of treatment. The management can be revolutionised by predicting those who are at high risk of developing post-operative complications and poor surgical outcomes by mere diagnosis of sarcopenia. This knowledge will benefit both the patients and the surgeons.

Correlation between anthropometric measurements and graft size in anterior cruciate ligament reconstruction: a systematic review and meta-analysis

PURPOSE

This systematic review and meta-analysis aimed to investigate the correlation between anthropometric measurements and graft size in anterior cruciate ligament (ACL) reconstruction.

METHODS

A systematic search of Ovid MEDLINE, Embase, and Cochrane Library databases was conducted for observational studies published until March 2023 that reported the relationship between anthropometric data [height, weight, body mass index (BMI), age, gender, thigh length, and circumference] and ACL graft size. Correlation coefficients (COR) and their associated 95% confidence intervals were used as the primary effect size. This review was conducted in line with PRISMA guidelines.

RESULTS

A total of 42 observational studies involving 7110 patients were included, with a mean age of 29.8 years. Statistically significant, moderately positive correlations were found between graft size and height (COR: 0.49; 95% CI: 0.41-0.57; p-value: < 0.001), weight (COR: 0.38; 95% CI: 0.31-0.44; p-value: < 0.001), thigh circumference (COR: 0.40; 95% CI: 0.19-0.58; p-value: < 0.001), and thigh length (COR: 0.35; 95% CI: 0.18-0.50; p-value: < 0.001). However, age and gender were insignificantly correlated with graft size (p-value: NS). A subanalysis based on graft type showed a significant positive correlation between height and graft diameter, which was more significant in the peroneus tendon than in hamstring grafts (COR: 0.76 vs. 0.45; p-value: 0.020).

CONCLUSION

This study demonstrated a moderate positive correlation between anthropometric measurements (height, weight, thigh circumference, and length) and ACL graft size, along with a weak positive correlation with BMI. Age and gender showed no significant correlation. These findings support the predictability and selection of ACL graft size based on pre-operative patient anthropometric data.

LEVEL OF EVIDENCE

Level of Evidence: IV. PROSPERO registration number: CRD42023416044.

Consensus-defined sarcopenia predicts adverse outcomes after elective abdominal surgery: meta-analysis

BACKGROUND

Sarcopenia refers to the progressive age- or pathology-associated loss of skeletal muscle. When measured radiologically as reduced muscle mass, sarcopenia has been shown to independently predict morbidity and mortality after elective abdominal surgery. However, the European Working Group on Sarcopenia in Older People (EWGSOP) recently updated their sarcopenia definition, emphasizing both low muscle 'strength' and 'mass'. The aim of this systematic review and meta-analysis was to determine the prognostic impact of this updated consensus definition of sarcopenia after elective abdominal surgery.

METHODS

MEDLINE, Embase, Scopus, and Cochrane Central Register of Controlled Trials (CENTRAL) databases were systematically searched for studies comparing prognostic outcomes between sarcopenic versus non-sarcopenic adults after elective abdominal surgery from inception to 15 June 2022. The primary outcomes were postoperative morbidity and mortality. Sensitivity analyses adjusting for confounding patient factors were also performed. Methodological quality assessment of studies was performed independently by two authors using the QUality in Prognosis Studies (QUIPS) tool.

RESULTS

Twenty articles with 5421 patients (1059 sarcopenic and 4362 non-sarcopenic) were included. Sarcopenic patients were at significantly greater risk of incurring postoperative complications, despite adjusted multivariate analysis (adjusted OR 1.56, 95 per cent c.i. 1.39 to 1.76). Sarcopenic patients also had significantly higher rates of in-hospital (OR 7.62, 95 per cent c.i. 2.86 to 20.34), 30-day (OR 3.84, 95 per cent c.i. 1.27 to 11.64), and 90-day (OR 3.73, 95 per cent c.i. 1.19 to 11.70) mortality. Sarcopenia was an independent risk factor for poorer overall survival in multivariate Cox regression analysis (adjusted HR 1.28, 95 per cent c.i. 1.13 to 1.44).

CONCLUSION

Consensus-defined sarcopenia provides important prognostic information after elective abdominal surgery and can be appropriately measured in the preoperative setting. Development of targeted exercise-based interventions that minimize sarcopenia may improve outcomes for patients who are undergoing elective abdominal surgery.

Low Preoperative Serum Creatinine is Common and Associated With Poor Outcomes After Nonemergent Inpatient Surgery

OBJECTIVE

To assess the association between low preoperative serum creatinine and postoperative outcomes.

BACKGROUND

The association between low creatinine and poor surgical outcomes is not well understood.

METHODS

We identified patients with creatinine in the 7 days preceding nonemergent inpatient surgery in the American College of Surgeons National Surgical Quality Improvement Program database from 2005 to 2020. Multivariable logistic regression was used to examine the association between creatinine and 30-day mortality and major complications.

RESULTS

Of 1,809,576 patients, 27.8% of males and 23.5% of females had low preoperative serum creatinine, 14.6% experienced complications, and 1.2% died. For males, compared with the reference creatinine of 0.85 to 1.04, those with serum creatinine ≤0.44 had 55% increased odds of mortality [ adjusted odds ratio (aOR), 1.55; 95% CI, 1.29-1.86] and 82% increased odds of major complications (aOR, 1.82; 95% CI, 1.69-1.97). Similarly, for females, compared with the reference range of 0.65 to 0.84, those with serum creatinine ≤0.44 had 49% increased odds of mortality (aOR, 1.49; 95% CI, 1.32-1.67) and 76% increased odds of major complications (aOR, 1.76; 95% CI, 1.70-1.83). These associations persisted for the total cohort, among those with mildly low albumin, and for those with creatinine values measured 8 to 30 days preoperatively.

CONCLUSIONS

A low preoperative creatinine is common and associated with poor outcomes after nonemergent inpatient surgery. A low creatinine may help identify high-risk patients who may benefit from further evaluation and optimization.

Supportive treatment during the periprocedural period of endoscopic treatment for pancreatic fluid collections: a critical review of current knowledge and future perspectives

Pancreatic fluid collections (PFCs) commonly develop as complications of acute pancreatitis and ductal disruption due to chronic pancreatitis. In the revised Atlanta classification, PFCs were classified based on the presence of necrosis and duration following the onset of acute pancreatitis. Interventions are required in cases of symptomatic pancreatic pseudocysts or walled-off necrosis (WON). In the management of these PFCs, endoscopic ultrasound-guided transluminal drainage and subsequent direct endoscopic necrosectomy for WON are increasingly utilized as less invasive treatment modalities compared to surgical debridement. To date, researchers have focused predominantly on the technical aspects of endoscopic therapy for symptomatic PFCs. Given the poor physical condition of patients receiving endoscopic treatment for PFCs, systemic support may have a substantial impact on the short- and long-term outcomes of these patients. A multidisciplinary approach is required to improve the clinical outcomes of patients with infected PFCs and their associated comorbidities. However, non-interventional support during the periprocedural period of endoscopic treatment of PFCs has not been fully discussed, and there have been considerable variations in the selection of treatment options between endoscopists and centers. To address these unmet needs in the clinical management of PFCs and promote future research to improve the clinical outcomes, we conducted a review of the literature within a multicenter consortium of expert endoscopists with specific expertise in the endoscopic treatment of PFCs. In this review, we summarize the current evidence on non-interventional supportive care (e.g., continuous lavage, medications, nutritional support, and antimicrobials) and propose potential topics for future research.

Acute Sarcopenia after Elective and Emergency Surgery

Sarcopenia is an increasingly recognised condition of loss of muscle mass and function. The European Working Group on Sarcopenia in Older People 2 (EWSOP2) updated their definition in 2018, emphasising the importance of low muscle strength in diagnosis. Acute sarcopenia has been arbitrarily defined as sarcopenia lasting less than 6 months. This review highlights the pathophysiology involved in muscle wasting following surgery, focussing on hormonal factors, inflammation, microRNAs, and oxidative stress. Biomarkers such as GDF-15, IGF-1 and various microRNAs may predict post-surgical muscle loss. The impact of existing sarcopenia on various types of surgery and incident muscle wasting following surgery is also described. The gaps in research found include the need for longitudinal studies looking in changes in muscle strength and quantity following surgery. Further work is needed to examine if biomarkers are replicated in other surgery to consolidate existing theories on the pathophysiology of muscle wasting.

Incidence and factors associated with postoperative delirium in patients undergoing transurethral resection of bladder tumor

Background

Postoperative delirium is an important complication after surgery, including urological surgery. This study evaluated the incidence of postoperative delirium and its associated factors after transurethral resection of bladder tumor in adult patients.

Methods

Patients aged ≥20 years who underwent elective transurethral resection of bladder tumor under general anesthesia from April 2016 to November 2020 were included. Patient demographic and intraoperative data, including the administration of 5-aminolevulinic acid and hypotension, defined as a mean arterial pressure value < 60 mmHg, were evaluated. The primary outcome was the incidence of postoperative delirium assessed using a chart-based method. The factors associated with postoperative delirium were explored using multiple logistic regression analysis. Postoperative lengths of stay between patients with and without postoperative delirium were compared using the Mann–Whitney U-test.

Results

Of 324 eligible patients with a median age of 76, 26 patients experienced postoperative delirium, with an incidence rate of 8.0% (95% confidence interval, 5.06–10.9). Age (odds ratio 1.13, 95% confidence interval 1.05–1.22, p = 0.001) and body mass index (odds ratio 0.83, 95% confidence interval 0.71–0.97, p = 0.02) were associated with postoperative delirium. Postoperative length of stay between patients with or without postoperative delirium was not significantly different (6 vs 6 days, p = 0.18).

Conclusions

The incidence of postoperative delirium after transurethral resection of bladder tumor under general anesthesia in this study was 8.0%. Older age and low body mass index were associated with development of postoperative delirium.

Association of physiological reserve measures with adverse outcomes following liver transplantation

Background and Aim

The comparative utility of physiological reserve measures in predicting important clinical outcomes following liver transplantation (LT) requires further study. The aim of this work was therefore to compare the utility of physiological reserve measures in predicting early adverse clinical outcomes post‐LT.

Methods

A single‐center, retrospective cohort study of LT patients consecutively recruited between 1 January 2015, and 31 August 2020. Outcomes measured were sepsis and death within 12 months of LT, hospital length of stay (LOS), and intensive care LOS. Physiological reserve measures were handgrip strength, mid‐arm muscle circumference, and cardiopulmonary exercise testing (CPET) measures. Analysis was performed using univariate and multivariate logistic regression for sepsis and death, and univariate and multivariate Cox regression for hospital and intensive care LOS.

Results

Data were obtained for 109 subjects. Patients were predominantly (64%) male with a median (interquartile range [IQR]) age of 57 (49–63) and median (IQR) Model for End‐Stage Liver Disease score of 16 (11–21). In multivariate analysis, the odds of sepsis were lower in patients in the highest versus lowest tertile (odds ratio = 0.004; 95% confidence interval [CI] 0.00–0.13; P = 0.002). Hospital LOS was linearly associated with handgrip strength (hazard ratio [HR] = 1.03; 95% CI 1.00–1.06; P = 0.03) in multivariate analysis. Intensive care LOS was associated with peak VO₂ (HR 1.83; 95% CI 1.06–3.16; P = 0.03) and V_E/VCO₂ slope (HR 0.71; 95% CI 0.58–0.88; P = 0.002) in multivariate analysis.

Conclusion

Handgrip strength and CPET both identify candidates at high risk of adverse outcomes after LT.

Body composition assessment and sarcopenia in patients with biliary tract cancer: A systematic review and meta-analysis

BACKGROUND

Sarcopenia, as assessed by body composition, can affect morbidity and survival in several gastrointestinal cancer. However, the impact of sarcopenia, referring to both quantity and quality of skeletal muscle, in biliary tract cancer (BTC) is debatable. We aimed to investigate the impact of sarcopenia on morbidity and mortality in patients with BTC.

METHODS

Electronic databases and trial registries were searched through July 2021 to perform random-effects meta-analyses. Study selection, data abstraction and quality assessment were independently performed using the Grading of Recommendations, Assessment, Development, and Evaluation approach.

RESULTS

Twenty-nine studies (4443 patients) were included; 28 used computed tomography and one used dual-energy X-ray absorptiometry to assess body composition. Eighteen studies reported the impact of pre-operative sarcopenia on postoperative outcomes; namely, sarcopenia increased postoperative complications (risk ratio = 1.23, 95% confidence interval [CI] = 1.07 to 1.41; I² = 2%), and decreased recurrence-free survival (hazard ratio [HR] = 2.20, 95% CI = 1.75 to 2.75; I² = 0%) in multivariable analyses. Low muscle quantity (HR = 2.26, 95% CI = 1.75 to 2.92; I² = 66%) and quality (HR = 1.75, 95% CI = 1.33 to 2.29; I² = 50%) decreased overall survival in multivariable analyses. The certainty of the evidence was low because of heterogeneity and imprecision.

CONCLUSIONS

In sarcopenia, low muscle quantity and quality by body composition conferred an independent risk of morbidity and mortality in patients with BTC. Further studies are needed to confirm these findings and mitigate risk.

Preoperative physical performance as predictor of postoperative outcomes in patients aged 65 and older scheduled for major abdominal cancer surgery: A systematic review

BACKGROUND

Abdominal cancer surgery is associated with considerable morbidity in older patients. Assessment of preoperative physical status is therefore essential. The aim of this review was to describe and compare the objective physical tests that are currently used in abdominal cancer surgery in the older patient population with regard to postoperative outcomes.

METHODS

Medline, Embase, CINAHL and Web of Science were searched until 31 December 2020. Non-interventional cohort studies were eligible if they included patients ≥65 years undergoing abdominal cancer surgery, reported results on objective preoperative physical assessment such as Cardiopulmonary Exercise Testing (CPET), field walk tests or muscle strength, and on postoperative outcomes.

RESULTS

23 publications were included (10 CPET, 13 non-CPET including Timed Up & Go, grip strength, 6-minute walking test (6MWT) and incremental shuttle walk test (ISWT)). Meta-analysis was precluded due to heterogeneity between study cohorts, different cut-off points, and inconsistent reporting of outcomes. In CPET studies, ventilatory anaerobic threshold and minute ventilation/carbon dioxide production gradient were associated with adverse outcomes. ISWT and 6MWT predicted outcomes in two studies. Tests addressing muscle strength and function were of limited value. No study compared different physical tests.

DISCUSSION

CPET has the ability to predict adverse postoperative outcomes, but it is time-consuming and requires expert assessment. ISWT or 6MWT might be a feasible alternative to estimate aerobic capacity. Muscle strength and function tests currently have limited value in risk prediction. Future research should compare the predictive value of different physical instruments with regard to postoperative outcomes in older surgical patients.