Preoperative exercise induces endothelial progenitor cell mobilisation in patients undergoing major surgery – A prospective randomised controlled clinical proof-of-concept trial

Prehabilitation to Enhance Vascular Surgery Outcomes: A Narrative Review

Prehabilitation, an emerging strategy, prepares patients for elective surgery by encouraging healthy behaviors, including physical exercise and healthy nutrition, while providing psychological support, to improve postoperative outcomes and foster healthier lifestyles. Despite growing interest, there is little research on prehabilitation. Specifically, studies involving prehabilitation in vascular surgery are heterogeneous with small sample sizes. This review aimed to investigate the reported positive impact of prehabilitation on vascular surgery patients, discuss prehabilitation models, highlight prehabilitation program-associated challenges, and suggest appropriate interventions. Prehabilitation improves physical fitness, reduces postoperative complications, and enhances overall recovery. Multimodal prehabilitation programs can positively impact vascular surgery patients, with benefits including improved cardiovascular fitness, reduced postoperative complications, shorter postoperative hospital stays, enhanced overall recovery, and improved quality of life. The currently reported prehabilitation programs are heterogeneous, with limitations regarding patient adherence and lack of long-term outcomes, posing challenges to their widespread adoption. Overall, prehabilitation shows promise for improving vascular surgery outcomes and fostering long-term healthy behaviors. The systematic implementation of prehabilitation in vascular surgery care pathways, overcoming reported limitations, and integrating multimodal prehabilitation into routine preoperative care hold potential benefits. This review underscores the need for high-quality research to establish best practices in prehabilitation and integrate them into the standard of care for vascular surgery patients.

FGR-associated placental insufficiency and capillary angiogenesis involves disruptions in human placental miRNAs and mRNAs

Fetal growth restriction (FGR) is one of the most common pregnancy complications culminating in adverse fetal outcome, including preterm birth, neonatal mortality and stillbirth. Compromised placental development and function, especially disruption in angiogenesis and inadequate nutrient supply are contributing factors. Fetal sex also influences placental function. Knowledge of gene expression changes and epigenetic factors contributing to placental dysfunction in FGR pregnancies will help identify biomarkers and help target interventions. This study tested the hypothesis that FGR pregnancies are associated with disruptions in miRNA - an epigenetic factor and mRNAs involving key mediators of angiogenesis and microvessel development. Changes in expression of key genes/proteins involved in placental dysfunction by RT-PCR and immunohistochemistry and miRNA changes by RNA sequencing were undertaken with term placenta from 12 control and 20 FGR pregnancies. Findings showed changes in expression of genes involved in steroidogenesis, steroid action, IGF family members, inflammatory cytokines and angiogenic factors in FGR pregnancies. In addition, upregulation of MIR451A and downregulation of MIR543 in placentas from FGR group with female newborns and upregulation of MIR520G in placentas from FGR group with male newborns were also noted. MIR451A and MIR543 have been implicated in angiogenesis. Consistent with gene changes, CD34, the microvessel angiogenesis marker, also showed reduced staining only in female FGR group. These findings provide evidence that epigentically regulated gene expression changes in angiogenesis and capillary development influence placental impairment in FGR pregnancies. Our preliminary observations also support for these changes to be driven in a sex-specific manner.

[Pre-rehabilitation of oncological patients before extensive abdominal and thoracic surgery: a literature review]

Surgery is one of the leading treatment methods of patients with primary or recurrent malignant neoplasms in the thoracic or abdominal cavity. Extensive abdominal interventions are accompanied by such adverse outcomes as blood loss, hypoxia, inflammation, blood clotting abnormality, emotional and cognitive disorders, that increases the incidence of serious complications and worsens the treatment outcome and life quality in weakened oncological patients. Multimodal pre-rehabilitation before surgery can significantly decrease the incidence and severity of postoperative complications. The rehabilitation complex includes exercise therapy, nutritional and psychological support, smoking cessation and pharmacotherapy. Currently, there are a number of questions facing rehabilitation specialists and oncologists, that are related to the determination of pre-rehabilitation optimal timing and process duration, the choice of specific physical exercises, determining the load intensity. This review presents a current view on understanding of surgical stress in extensive abdominal interventions, its effect on the oncological process course, summarizes the experience of last years in choosing pre-rehabilitation program taking into account pathogenetic mechanisms of surgical stress and individual patient's characteristics. Special attention is paid to the comparison of physical exercises' various types, their action mechanisms at different stages of pathological process, the issues of load dosing during pre-rehabilitation activities.

Sex-related differences in functional capacity and its implications in risk stratification before major non-cardiac surgery: a post hoc analysis of the international METS study

Background

Poor functional capacity has been identified as an important modifiable risk factor for postoperative complications. Cardiopulmonary exercise testing (CPET) provides objective parameters of functional capacity (e.g., oxygen consumption at peak exercise, peak VO2), with significant prognostication for postoperative complications. However, sex-specific thresholds for functional capacity to predict surgical risk are yet to be established. Therefore, we performed a post hoc analysis of the international, multicentre, prospective observational METS (Measurement of Exercise Tolerance before Surgery) study to evaluate if sex-specific thresholds of peak VO2 improve risk prediction of postoperative complications.

Methods

We undertook a post hoc analysis (HREC/71824/PMCC) of the METS study, which was performed between March 2013 and March 2016. We investigated whether sex-specific differences exist for CPET-derived parameters and associated thresholds for predicting postoperative complications in this large cohort of patients that had major non-cardiac surgery (n = 1266). Logistic regression models were analyzed for the association of low peak VO2 with moderate-to-severe in-hospital postoperative complications. Optimal sex-specific peak VO2 thresholds were obtained by maximizing the Youden index of receiver operating characteristic (ROC) curves. Finally, multivariable logistic regression models tested the resulting sex-specific thresholds against the established non-sex-specific peak VO2 threshold (14 mL kg-1 min-1) adjusted for clinically relevant features such as comorbidities and surgical complexity. Models were evaluated by bootstrapping optimism-corrected area under the ROC curve and the net reclassification improvement index (NRI).

Findings

Female patients (n = 480) had a lower mean (SD) peak VO2 than males (16.7 (4.9) mL kg-1 min-1 versus 21.2 (6.5) mL kg-1 min-1, p < 0.001) and a lower postoperative complication rate (10.4% versus 15.3%; p = 0.018) than males (n = 786). The optimal peak VO2 threshold for predicting postoperative complications was 12.4 mL kg-1 min-1 for females and 22.3 mL kg-1 min-1 for males, respectively. In the multivariable regression model, low non-sex-specific peak VO2 did not independently predict postoperative complications. In contrast, low sex-specific peak VO2 was an independent predictor of postoperative complications (OR 2.29; 95% CI: 1.60, 3.30; p < 0.001). The optimism-corrected AUC-ROC of the sex-specific model was higher compared with the non-sex-specific model (0.73 versus 0.7; DeLong's test: p = 0.021). The sex-specific model classified 39% of the patients more correctly than the baseline model (NRI = 0.39; 95% CI: 0.24, 0.55). In contrast, the non-sex-specific model only classified 9% of the patients more correctly when compared against the baseline model (NRI = 0.09; 95% CI: -0.04, 0.22).

Interpretation

Our data report sex-specific differences in preoperative CPET-derived functional capacity parameters. Sex-specific peak VO2 thresholds identify patients at increased risk for postoperative complications with a higher discriminatory ability than a sex-unspecific threshold. As such, sex-specific threshold values should be considered in preoperative CPET to potentially improve risk stratification and to guide surgical decision-making, including eligibility for surgery, preoperative optimization strategies (prehabilitation) or seeking non-surgical options.

Funding

There was no funding for the present study. The original METS study was funded by Canadian Institutes of Health Research, Heart and Stroke Foundation of Canada, Ontario Ministry of Health and Long-Term Care, Ontario Ministry of Research, Innovation and Science, UK National Institute of Academic Anaesthesia, UK Clinical Research Collaboration, Australian and New Zealand College of Anaesthetists, and Monash University.

Clinical Potential of Hydrogen Sulfide in Peripheral Arterial Disease

Peripheral artery disease (PAD) affects more than 230 million people worldwide. PAD patients suffer from reduced quality of life and are at increased risk of vascular complications and all-cause mortality. Despite its prevalence, impact on quality of life and poor long-term clinical outcomes, PAD remains underdiagnosed and undertreated compared to myocardial infarction and stroke. PAD is due to a combination of macrovascular atherosclerosis and calcification, combined with microvascular rarefaction, leading to chronic peripheral ischemia. Novel therapies are needed to address the increasing incidence of PAD and its difficult long-term pharmacological and surgical management. The cysteine-derived gasotransmitter hydrogen sulfide (H₂S) has interesting vasorelaxant, cytoprotective, antioxidant and anti-inflammatory properties. In this review, we describe the current understanding of PAD pathophysiology and the remarkable benefits of H₂S against atherosclerosis, inflammation, vascular calcification, and other vasculo-protective effects.