Ventilatory efficiency as a prognostic factor for postoperative complications in patients undergoing elective major surgery: a systematic review

BACKGROUND

Major surgery is associated with high complication rates. Several risk scores exist to assess individual patient risk before surgery but have limited precision. Novel prognostic factors can be included as additional building blocks in existing prediction models. A candidate prognostic factor, measured by cardiopulmonary exercise testing, is ventilatory efficiency (VE/VCO2). The aim of this systematic review was to summarise evidence regarding VE/VCO2 as a prognostic factor for postoperative complications in patients undergoing major surgery.

METHODS

A medical library specialist developed the search strategy. No database-provided limits, considering study types, languages, publication years, or any other formal criteria were applied to any of the sources. Two reviewers assessed eligibility of each record and rated risk of bias in included studies.

RESULTS

From 10,082 screened records, 65 studies were identified as eligible. We extracted adjusted associations from 32 studies and unadjusted from 33 studies. Risk of bias was a concern in the domains 'study confounding' and 'statistical analysis'. VE/VCO2 was reported as a prognostic factor for short-term complications after thoracic and abdominal surgery. VE/VCO2 was also reported as a prognostic factor for mid- to long-term mortality. Data-driven covariable selection was applied in 31 studies. Eighteen studies excluded VE/VCO2 from the final multivariable regression owing to data-driven model-building approaches.

CONCLUSIONS

This systematic review identifies VE/VCO2 as a predictor for short-term complications after thoracic and abdominal surgery. However, the available data do not allow conclusions about clinical decision-making. Future studies should select covariables for adjustment a priori based on external knowledge.

SYSTEMATIC REVIEW PROTOCOL

PROSPERO (CRD42022369944).

Measurement and optimization of perioperative risk among patients undergoing surgery for esophageal cancer

Esophagectomy is an exemplar of complex oncological surgery and is associated with a relatively high risk of major morbidity and mortality. In the modern era, where specific complications are targeted in prevention and treatment pathways, and where the principles of enhanced recovery after surgery are espoused, optimum outcomes are targeted via a number of approaches. These include comprehensive clinical and physiological risk assessment, specialist perioperative care by a high-volume team, and multimodal inputs throughout the patient journey that aim to preserve or restore nutritional deficits, muscle mass and function.

Effectiveness of prehabilitation during neoadjuvant therapy for patients with esophageal or gastroesophageal junction cancer: a systematic review

Progression of the physical weakness during neoadjuvant therapy (NAT) in patients with esophageal or gastroesophageal junction cancer is a serious problem; however, prehabilitation during NAT has the potential to overcome the unmet need. Nevertheless, systematic reviews on this topic have not been summarized. Therefore, this systematic review aimed to determine prehabilitation's effectiveness, acceptability, and safety during NAT for patients with esophageal or gastroesophageal junction cancer. An electronic search was performed in the MEDLINE, Web of Science, CENTRAL, CINAHL, and PEDro databases. A meta-analysis was conducted to assess the effectiveness of prehabilitation during NAT, along with a descriptive analysis of acceptance and safety. This study analyzed data from three randomized controlled trials (RCTs) and nine non-RCTs involving 664 patients. The meta-analysis of two RCTs demonstrated that prehabilitation during NAT may be more effective than usual care in enhancing tolerance to NAT and grip strength; moreover, one RCT and three non-RCTs revealed that prehabilitation may reduce the risk of postoperative complications. The adherence rates for exercise programs in two RCTs and seven non-RCTs were 55-76%. Additionally, two studies reported a 76% adherence rate for multimodal prehabilitation programs, including exercise, dietary, and psychological care. Six studies reported no serious prehabilitation-related adverse events during NAT. Prehabilitation during NAT may be a safe and beneficial intervention strategy for patients with esophageal or gastroesophageal junction cancer. However, the investigation of strategies to enhance adherence is essential. Furthermore, additional high-quality RCTs are needed to examine the effect of prehabilitation during NAT.

The association between cardiopulmonary exercise testing and postoperative outcomes in patients with lung cancer undergoing lung resection surgery: A systematic review and meta-analysis

BACKGROUND

Exercise capacity should be determined in all patients undergoing lung resection for lung cancer surgery and cardiopulmonary exercise testing (CPET) remains the gold standard. The purpose of this study was to investigate associations between preoperative CPET and postoperative outcomes in patients undergoing lung resection surgery for lung cancer through a review of the existing literature.

METHODS

A search was conducted on PubMed, Scopus, Cochrane Library and CINAHL from inception until December 2022. Studies investigating associations between preoperative CPET and postoperative outcomes were included. Risk of bias was assessed using the QUIPS tool. A random effect model meta-analysis was performed. I2 > 40% indicated a high level of heterogeneity.

RESULTS

Thirty-seven studies were included with 6450 patients. Twenty-eight studies had low risk of bias. [Formula: see text] peak is the oxygen consumption at peak exercise and serves as a marker of cardiopulmonary fitness. Higher estimates of [Formula: see text] peak, measured and as a percentagege of predicted, showed significant associations with a lower risk of mortality [MD: 3.66, 95% CI: 0.88; 6.43 and MD: 16.49, 95% CI: 6.92; 26.07] and fewer complications [MD: 2.06, 95% CI: 1.12; 3.00 and MD: 9.82, 95% CI: 5.88; 13.76]. Using a previously defined cutoff value of > 15mL/kg/min for [Formula: see text] peak, showed evidence of decreased odds of mortality [OR: 0.55, 95% CI: 0.28-0.81] and but not decreased odds of postoperative morbidity [OR: 0.82, 95% CI: 0.64-1.00]. There was no relationship between [Formula: see text] slope, which depicts ventilatory efficiency, with mortality [MD: -9.60, 95% CI: -27.74; 8.54] however, patients without postoperative complications had a lower preoperative [Formula: see text] [MD: -2.36, 95% CI: -3.01; -1.71]. Exercise load and anaerobic threshold did not correlate with morbidity or mortality. There was significant heterogeneity between studies.

CONCLUSIONS

Estimates of cardiopulmonary fitness as evidenced by higher [Formula: see text] peak, measured and as a percentage of predicted, were associated with decreased morbidity and mortality. A cutoff value of [Formula: see text] peak > 15mL/kg/min was consistent with improved survival but not with fewer complications. Ventilatory efficiency was associated with decreased postoperative morbidity but not with improved survival. The heterogeneity in literature could be remedied with large scale, prospective, blinded, standardised research to improve preoperative risk stratification in patients with lung cancer scheduled for lung resection surgery.

Clinical tools to assess functional capacity before elective non-cardiac surgery: a scoping review protocol

OBJECTIVE

The objective of this scoping review is to map the evidence on clinical tools to assess functional capacity prior to elective non-cardiac surgery.

INTRODUCTION

Functional capacity is a strong prognostic indicator before surgery, which can be used to identify patients at elevated risk of postoperative complications, yet, there is no consensus on which clinical tools should be used to assess functional capacity in patients prior to non-cardiac surgery.

INCLUSION CRITERIA

This review will consider any randomized or non-randomized studies that evaluate the performance of a functional capacity assessment tool in adults (≥18 years) prior to non-cardiac surgery. For studies to be included, the tool must be used clinically for risk stratification. We will exclude studies on lung and liver transplant surgery, as well as ambulatory procedures performed under local anesthesia.

METHODS

The review will be conducted in line with the JBI methodology for scoping reviews. A peer-reviewed search strategy will be used to query relevant databases (ie, MEDLINE, Embase, EBM Reviews). Additional sources of evidence will include databases of non-peer-reviewed literature and the reference lists of included studies. Two independent reviewers will identify eligible studies in 2 stages: stage 1, based on titles and abstracts; and stage 2, based on full texts. Information on study details, measurement properties, pragmatic qualities, and/or clinical utility metrics will be charted in duplicate onto standardized data collection forms. The results will be presented using descriptive summaries, frequency tables, and visual plots that highlight the extent of evidence and remaining gaps in the validation process of each tool.

REVIEW REGISTRATION

Open Science Framework https://osf.io/6nfht.

Preoperative risk modelling for oesophagectomy: A systematic review

BACKGROUND

Oesophageal cancer is a frequently observed and lethal malignancy worldwide. Surgical resection remains a realistic option for curative intent in the early stages of the disease. However, the decision to undertake oesophagectomy is significant as it exposes the patient to a substantial risk of morbidity and mortality. Therefore, appropriate patient selection, counselling and resource allocation is important. Many tools have been developed to aid surgeons in appropriate decision-making.

AIM

To examine all multivariate risk models that use preoperative and intraoperative information and establish which have the most clinical utility.

METHODS

A systematic review of the MEDLINE, EMBASE and Cochrane databases was conducted from 2000-2020. The search terms applied were ((Oesophagectomy) AND (Risk OR predict OR model OR score) AND (Outcomes OR complications OR morbidity OR mortality OR length of stay OR anastomotic leak)). The applied inclusion criteria were articles assessing multivariate based tools using exclusively preoperatively available data to predict perioperative patient outcomes following oesophagectomy. The exclusion criteria were publications that described models requiring intra-operative or post-operative data and articles appraising only univariate predictors such as American Society of Anesthesiologists score, cardiopulmonary fitness or pre-operative sarcopenia. Articles that exclusively assessed distant outcomes such as long-term survival were excluded as were publications using cohorts mixed with other surgical procedures. The articles generated from each search were collated, processed and then reported in accordance with PRISMA guidelines. All risk models were appraised for clinical credibility, methodological quality, performance, validation, and clinical effectiveness.

RESULTS

The initial search of composite databases yielded 8715 articles which reduced to 5827 following the deduplication process. After title and abstract screening, 197 potentially relevant texts were retrieved for detailed review. Twenty-seven published studies were ultimately included which examined twenty-one multivariate risk models utilising exclusively preoperative data. Most models examined were clinically credible and were constructed with sound methodological quality, but model performance was often insufficient to prognosticate patient outcomes. Three risk models were identified as being promising in predicting perioperative mortality, including the National Quality Improvement Project surgical risk calculator, revised STS score and the Takeuchi model. Two studies predicted perioperative major morbidity, including the predicting postoperative complications score and prognostic nutritional index-multivariate models. Many of these models require external validation and demonstration of clinical effectiveness.

CONCLUSION

Whilst there are several promising models in predicting perioperative oesophagectomy outcomes, more research is needed to confirm their validity and demonstrate improved clinical outcomes with the adoption of these models.

Identifying the limitations of cardiopulmonary exercise testing prior to esophagectomy using a pooled analysis of patient-level data

Preoperative cardiopulmonary exercise testing (CPET) provides an objective assessment of aerobic fitness in patients undergoing surgery. While peak oxygen uptake during exercise (VO2peak) and anaerobic threshold have demonstrated a moderate correlation with the development of complications following esophagectomy, no clinically useful threshold values have been defined. By pooling patient level data from existing studies, we aimed to define optimal thresholds for preoperative CPET parameters to predict patients at high risk of postoperative complications. Studies reporting on the relationship between preoperative CPET variables and post-esophagectomy complications were determined from a comprehensive literature search. Patient-level data were obtained from six contributing centers for pooled-analyses. Outcomes of interest included cardiopulmonary and non-cardiopulmonary complications, unplanned intensive care unit readmission, and 90-day and 12-month all-cause mortality. Receiver operating characteristic curves and logistic regression models estimated the predictive value of CPET parameters for each individual outcome of interest. This analysis comprised of 621 patients who underwent CPET prior to esophagectomy during the period from January 2004 to March 2017. For both anaerobic threshold and VO2peak, none of the receiver operating characteristic curves achieved an area under the curve value > 0.66 for the outcomes of interest. The discriminatory ability of CPET for determining high-risk patients was found to be poor in patients undergoing an esophagectomy. CPET may only carry an adjunct role to clinical decision-making.

A feasibility trial of prehabilitation before oesophagogastric cancer surgery using a multi-component home-based exercise programme: the ChemoFit study

BACKGROUND

Treatment for locally advanced oesophagogastric adenocarcinoma involves neoadjuvant chemotherapy which has a negative impact on patient fitness. Using 'prehabilitation' to increase activity levels and fitness may affect physiology, postoperative outcomes and improve patient wellbeing and quality of life. The aims of the trial were to address the feasibility and acceptability of recruiting participants to a home-based prehabilitation programme and provide data to allow design of future studies.

METHODS

We recruited patients to a single-arm feasibility trial of home-based exercise prehabilitation. Eligible patients were aged ≥18years, had operable oesophageal or gastric adenocarcinoma and were receiving neoadjuvant chemotherapy at our tertiary referral hospital. All participants commenced a home-based exercise programme utilising pedometers and step counting to target daily aerobic exercise sessions alongside daily strengthening exercises. A weekly telephone consultation directed the exercise programme and facilitated weekly data collection. The primary (feasibility) outcomes for the trial were (a) recruitment rate, (b) completion rate, (c) engagement with the programme (use of pedometers, recording step counts, telephone consultations) and (d) compliance with exercise sessions, exercise intensity and strengthening exercises.

RESULTS

There were 42 patients recruited, and the recruitment rate was 72.4% (42/58). 92.3% (36/39) of patients completed the exercise programme. There was 98.7% (IQR 93.2-100.0%) compliance with wearing a pedometer and recording data, and 100.0% (IQR 93.1-100.0%) compliance with a weekly telephone consultation. Exercise sessions and strengthening exercises were completed 70.2% (IQR 53.1-88.9%) and 69.4% (IQR 52.1-84.3%) of the time, respectively. Appropriate exercise intensity was recorded 96% (IQR 85.4-99.4%) of the time. There were no adverse events. Participants were enrolled in the exercise programme for a median of 91 days (IQR 84 to 105 days).

CONCLUSIONS

The results of this trial support the feasibility and acceptability of recruiting participants to an appropriately powered randomised controlled trial of prehabilitation.

TRIAL REGISTRATION

Clinicaltrials.gov NCT04194463 . Registered on 11th December 2019-retrospectively registered.

Cardiopulmonary exercise testing for cardiovascular risk assessment in patients undergoing gastric and oesophageal cancer surgery: results from a prospective interventional cohort study

Background

Cardiopulmonary exercise testing (CPET) has shown to be useful for preoperative risk stratification in various types of intra-abdominal and thoracic surgery. However, data about the predictive value of CPET for cardiovascular outcome after gastric or oesophageal cancer surgery are inconclusive. The aim of this study was to evaluate the prognostic value of CPET parameters for the prediction of cardiovascular complications in patients with this type of surgery.

Methods

This is a prospective single-centre interventional cohort study including 200 consecutive patients who underwent elective surgery for oesophageal and/or gastric cancer. Symptom-limited CPET was performed preoperatively to evaluate the potential of various test-derived parameters including anaerobic threshold (AT) to predict cardiovascular complications within 30 days after surgery.

Results

200 patients (mean age 68±14.2 years) met inclusion and exclusion criteria: oesophageal surgery 54 pts, gastric surgery 132 pts and combined oesophageal/gastric surgery 14 pts. 41/200 pts (20.5%) experienced cardiovascular complications during and within 30 days after surgery including 4 non-fatal myocardial infarctions (2%), 1 stroke (0.5%); 6 dead from cardiovascular causes (3%) and less serious complications in 30 patients (15%) including angina attacks and antiarrhythmic therapy for ventricular arrhythmias or for atrial fibrillation/flutter. Results from preoperative CPET indicate that an AT level below 11 mL/kg/min was highly predictive for any cardiovascular complication (p=0.02, OR 6.33, 95% CI 1.78 to 22.47). An AT level <9.5 had the best predictive accuracy for major perioperative cardiac complications (sensitivity 93%, specificity 68%, positive predicative value 75%, negative predicative value 98.8%).

Conclusion

CPET is a useful perioperative risk assessment tool for patients undergoing surgery for oesophageal and gastric cancer, which carries a particularly high risk for cardiovascular complications. An AT <9.5 mL/kg/min turned out to be the most reliable predictor for major cardiovascular complications.

Preoperative functional capacity and postoperative outcomes following abdominal and pelvic cancer surgery: a systematic review and meta-analysis

BACKGROUND

There is clinical uncertainty regarding an association between preoperative functional capacity of cancer patients, and postoperative outcomes. The aim of this systematic review and meta-analysis is to investigate whether poor performance on preoperative six-minute walk test (6MWT) or five-times sit to stand test (5STS) is associated with worse postoperative complication rates and prolonged length of hospital stay (LOS) in cancer patients.

METHODS

An electronic search was performed from earliest available record to 26th February 2021 in MEDLINE, Embase and AMED. Studies investigating the association between preoperative physical function (measured using either 6MWT or 5STS) and postoperative outcomes (complications and LOS) in patients with gastrointestinal, abdominal and pelvic cancers were included. Risk of bias was assessed using the Quality in Prognosis Studies (QUIPS) tool. Where possible, summary odds ratios (OR) or mean differences (MD), and 95% confidence intervals (CI) were calculated using random-effect models.

RESULTS

Five studies (379 patients) were included, of which none utilized the 5STS. Overall, studies were rated as having low to moderate risk of bias. Higher preoperative performance on the 6MWT (≥400 m) was associated with low grade postoperative complications (OR = 0.38; 95% CI = 0.15-0.95) but was not associated with a shorter LOS (MD = 3.29; 95%CI = -1.07-7.66).

CONCLUSION

The available evidence suggests that in cancer patients, a higher preoperative functional capacity may be associated with reduced postoperative complications. Conversely, there is no significant association between preoperative function and LOS. Further high-quality studies are needed in this area, including studies involving 5STS.

Peri-operative approach to esophagectomy: a narrative review from the anesthesiological standpoint

Objective

This review summarizes the peri-operative anesthesiological approaches to esophagectomy considering the best up-to-date, evidence-based medicine, discussed from the anesthesiologist’s standpoint.

Background

Esophagectomy is the only curative therapy for esophageal cancer. Despite the many advancements made in the surgical treatment of this tumour, esophagectomy still carries a morbidity rate reaching 60%. Patients undergoing esophagectomy should be referred to high volume centres where they can receive a multidisciplinary approach to treatment, associated with better outcomes. The anesthesiologist is the key figure who should guide the peri-operative phase, from diagnosis through to post-surgery rehabilitation. We performed an updated narrative review devoted to the study of anesthesia management for esophagectomy in cancer patients.

Methods

We searched MEDLINE, Scopus and Google Scholar databases from inception to May 2021. We used the following terms: “esophagectomy”, “esophagectomy AND pre-operative evaluation”, “esophagectomy AND protective lung ventilation”, “esophagectomy AND hemodynamic monitoring” and “esophagectomy AND analgesia”. We considered only articles with abstract written in English and available to the reader. We excluded single case-reports.

Conclusions

Pre-operative anesthesiological evaluation is mandatory in order to stratify and optimize any medical condition. During surgery, protective ventilation and judicious fluid management are the cornerstones of intraoperative “protective anesthesia”. Post-operative care should be provided by an intensive care unit or high-dependency unit depending on the patient’s condition, the type of surgery endured and the availability of local resources. The provision of adequate post-operative analgesia favours early mobilization and rapid recovery. Anesthesiologist has an important role during the peri-operative care for esophagectomy. However, there are still some topics that need to be further studied to improve the outcome of these patients.

Exercise capacity in the stair-climbing test predicts outcomes of operable esophageal cancer in minimally invasive era

INTRODUCTION

The risk of complications after esophagectomy highlights the need for careful preoperative assessment. Aim was to assess whether stair-climbing test (SCT) could predict outcomes of patients with operable esophageal cancer in minimally invasive era.

MATERIALS AND METHODS

Patients with esophageal cancer were evaluated for surgical treatment in Central Finland Central Hospital from 2012 to March 2021. Of evaluated 162 patients, 138 were scheduled to eventually undergo surgery. The exercise capacity was evaluated with symptom limited SCT. Patients were divided into four study groups on intent-to-treat basis: surgery and the SCT >14 m (Group 1), surgery and the SCT <11 m (Group 2), non-surgical therapy and the SCT <11 m (Group 3) and non-surgical therapy and the SCT >14 m (Group 4). Results were adjusted for confounders.

RESULTS

Major complication rate was 10.1% vs 40.0% between Group 1 and 2 (p = 0.006), and 90-day mortality 0% vs 20.0% (p < 0.001). Overall survival rates in Groups 1-4 at 1-year were 92.3% vs 72.2% vs 46.8% vs 81.8%, at 3-year 68.5% vs 52.7% vs 15.6% vs 27.3% and at 5-year 58.7% vs 39.5% vs 0% vs 0%, respectively (p < 0.001). In adjusted analysis when compared to Group 1, other groups had increased 5-year mortality hazard (Group 2 HR 2.88 (95% CI 1.25-6.63), Group 3 HR 15.6 (95% CI 5.57-43.5) and Group 4 HR 5.35 (95% CI 2.08-13.7)).

CONCLUSION

Exercise capacity measured with SCT in esophageal cancer patients is a strong predictor of complications and survival, and is a potential parameter to be included in any risk or prognostic models.

Preoperative Cardiopulmonary Exercise Test Associated with Postoperative Outcomes in Patients Undergoing Cancer Surgery: A Systematic Review and Meta-Analyses

BACKGROUNDS

There is mixed evidence on the value of preoperative cardiorespiratory exercise test (CPET) to predict postoperative outcomes in patients undergoing a cancer surgical procedure. The purpose of this review was to investigate the association between preoperative CPET variables and postoperative complications, length of hospital stay, and quality of life in patients undergoing cancer surgery.

METHODS

A search was conducted on MEDLINE, Embase, AMED, and Web of science from inception to April 2020. Cohort studies investigating the association between preoperative CPET variables, including peak oxygen uptake (peak VO₂), anaerobic threshold (AT), or ventilatory equivalent for carbon dioxide (V_E/V_CO2), and postoperative outcomes (complications, length of stay, and quality of life) were included. Risk of bias was assessed using the QUIPS tool. A random-effect model meta-analysis was performed whenever possible.

RESULTS

Fifty-two unique studies, including 10,030 patients were included. Overall, most studies were rated as having low risk of bias. Higher preoperative peak VO₂ was associated with absence of postoperative complications (mean difference [MD]: 2.28; 95% confidence interval [CI]: 1.26-3.29) and no pulmonary complication (MD: 1.47; 95% CI: 0.49-2.45). Preoperative AT and V_E/V_CO2 also demonstrated some positive trends. None of the included studies reported a negative trend.

CONCLUSIONS

This systematic review and meta-analysis demonstrated a significant association between superior preoperative CPET values, especially peak VO₂, and better postoperative outcomes. The assessment of preoperative functional capacity in patients undergoing cancer surgery has the potential to facilitate treatment decision making.

Perioperative risk assessment - focus on functional capacity

PURPOSE OF REVIEW

This review examines how functional capacity informs preoperative risk stratification, as well as strengths and limitations of options for estimating functional capacity.

RECENT FINDINGS

Functional capacity (or cardiopulmonary fitness) overlaps with other important characteristics, including muscular strength, balance, and frailty. Poor functional capacity is associated with postoperative morbidity, especially noncardiovascular complications. Both patient interviews and exercise tests are used to assess functional capacity. The usual approach of an unstructured patient interview does not predict outcomes. Structured interviews that incorporate validated questionnaires (Duke Activity Status Index) or standardized questions about physical activity (ability to climb stairs) do predict moderate-or-severe complications and cardiovascular complications. Among exercise tests, cardiopulmonary exercise testing (CPET) has shown the most consistent association with risks of complications. Other tests (6-min walk test, incremental shuttle walk test, stair climbing) might predict complications, but still require further high-quality evaluation.

SUMMARY

A straightforward way to better assess functional capacity is a structured interview with validated questionnaires or standardized questions about physical activities. Functional capacity can also be assessed by exercise tests, with the strongest evidence supporting CPET. Although some simpler exercise tests have shown promise, more research remains needed to better define their role in preoperative evaluation.