Accuracy and Methodological Considerations of Steep Ramp Test-Estimated Oxygen Uptake at Peak Exercise in Preoperative Risk Assessment for Esophagectomy

Steep ramp test protocol for preoperative risk assessment and short-term high-intensity interval training to evaluate, improve, and monitor cardiorespiratory fitness in surgical oncology.

The widespread implementation of a preoperative assessment of aerobic capacity requires a practical field test. This study investigated the validity of the modified steep ramp test (SRT) for evaluating preoperative aerobic capacity and to evaluate its usefulness for preoperative risk assessment in patients planned for pancreatic surgery. Patients scheduled for pancreatic surgery who preoperatively performed cardiopulmonary exercise testing (CPET) and the modified SRT within 14days were included. To assess its criterion validity, the correlation between the achieved work rate at peak exercise (WRpeak) at the modified SRT and oxygen uptake (VO2) at peak exercise (VO2peak) during CPET was determined. To evaluate the ability of the modified SRT to correctly classify patients as fit or unfit, receiver operating characteristic (ROC) analyses were performed based on the CPET VO2peak cutoff 18.0ml.kg-1.min-1 and VO2 at the ventilatory anaerobic threshold (VAT) cutoff 11.0ml.kg-1.min-1. Forty-eight patients (21 females) aged 68.7±7.6years were included. Modified SRT WRpeak (W/kg) demonstrated a very strong correlation with CPET VO2peak (ρ=0.865, r=0.926). The modified SRT WRpeak cutoff to most accurately classify patients as fit or unfit was 2.095W/kg for the CPET VO2peak cutoff (area under the curve (AUC) of 0.948) and the CPET VO2 at the VAT cutoff (AUC of 0.814). The modified SRT is a valid short-term practical exercise test to preoperatively assess aerobic capacity in patients undergoing pancreatic surgery. A modified SRT performance below 2.1W/kg seems clinically most suitable to select candidates for further preoperative CPET evaluation and/or prehabilitation, given its positive and negative predictive value.

Patients with a low cardiorespiratory fitness (CRF) undergoing colorectal cancer surgery have a high risk for postoperative complications. Cardiopulmonary exercise testing (CPET) to assess CRF is the gold standard for preoperative risk assessment. To aid interpretation of raw breath-by-breath data, different methods of data-averaging can be applied. This study aimed to investigate the influence of different data-averaging intervals on CPET variables used for preoperative risk assessment, as well as to evaluate whether different data-averaging intervals influence preoperative risk assessment. A total of 21 preoperative CPETs were interpreted by two exercise physiologists using stationary time-based data-averaging intervals of 10, 20, and 30 seconds and rolling average intervals of 3 and 7 breaths. Mean values of CPET variables between different data averaging intervals were compared using repeated measures ANOVA. The variables of interest were oxygen uptake at peak exercise (VO2peak), oxygen uptake at the ventilatory anaerobic threshold (VO2VAT), oxygen uptake efficiency slope (OUES), the ventilatory equivalent for carbon dioxide at the ventilatory anaerobic threshold (VE/VCO2VAT), and the slope of the relationship between the minute ventilation and carbon dioxide production (VE/VCO2-slope). Between data-averaging intervals, no statistically significant differences were found in the mean values of CPET variables except for the ventilatory equivalent for carbon dioxide at the ventilatory anaerobic threshold (P = 0.001). No statistically significant differences were found in the proportion of patients classified as high or low risk regardless of the used data-averaging interval. There appears to be no significant or clinically relevant influence of the evaluated data-averaging intervals on the mean values of CPET outcomes used for preoperative risk assessment. Clinicians may choose a data-averaging interval that is appropriate for optimal interpretation and data visualization of the preoperative CPET. Nevertheless, caution should be taken as the chosen data-averaging interval might lead to substantial within-patient variation for individual patients. Prospectively registered at ClinicalTrials.gov (NCT05353127).

ObjectiveProviding an overview of the clinimetric properties of the steep ramp test (SRT)—a short-term maximal exercise test—to assess cardiorespiratory fitness (CRF), describing its underlying physiological responses, and summarizing its applications in current clinical and research practice. Data SourcesMEDLINE (through PubMed), CINAHL Complete, Cochrane Library, EMBASE, and PsycINFO were searched for studies published up to July 2023, using keywords for SRT and CRF. Study SelectionEligible studies involved the SRT as research subject or measurement instrument and were available as full text articles in English or Dutch. Data ExtractionTwo independent assessors performed data extraction. Data addressing clinimetric properties, physiological responses, and applications of the SRT were tabulated. Data SynthesisIn total, 370 studies were found, of which 39 were included in this study. In several healthy and patient populations, correlation coefficients between the work rate at peak exercise (WRpeak) attained at the SRT and oxygen uptake at peak exercise during cardiopulmonary exercise testing (CPET) ranged from .771-.958 (criterion validity). Repeated measurements showed intraclass correlation coefficients ranging from .908-.996 for WRpeak attained with the first and second SRT (test-retest reliability). Physiological parameters, like heart rate and minute ventilation at peak exercise, indicated that the SRT puts a lower burden on the cardiopulmonary system compared to CPET. The SRT is mostly used to assess CRF, among others as part of preoperative risk assessment, and to personalize interval training intensity. ConclusionsThe SRT is a practical short-term maximal exercise test that is valid for CRF assessment and to monitor changes in CRF over time in various healthy and patient populations. Its clinimetric properties and potential applications make the SRT of interest for a widespread implementation of CRF assessment in clinical and research practice and for personalizing training intensity and monitoring longitudinal changes in CRF.

IntroductionPatients with a low cardiorespiratory fitness (CRF) undergoing colorectal cancer surgery have a high risk for postoperative complications. Cardiopulmonary exercise testing (CPET) to assess CRF is the gold standard for preoperative risk assessment. To aid interpretation of raw breath-by-breath data, different methods of data-averaging can be applied. This study aimed to investigate the influence of different data-averaging intervals on CPET variables used for preoperative risk assessment, as well as to evaluate whether different data-averaging intervals influence preoperative risk assessment.MethodsA total of 21 preoperative CPETs were interpreted by two exercise physiologists using stationary time-based data-averaging intervals of 10, 20, and 30 seconds and rolling average intervals of 3 and 7 breaths. Mean values of CPET variables between different data averaging intervals were compared using repeated measures ANOVA. The variables of interest were oxygen uptake at peak exercise (VO2peak), oxygen uptake at the ventilatory anaerobic threshold (VO2VAT), oxygen uptake efficiency slope (OUES), the ventilatory equivalent for carbon dioxide at the ventilatory anaerobic threshold (VE/VCO2VAT), and the slope of the relationship between the minute ventilation and carbon dioxide production (VE/VCO2-slope).ResultsBetween data-averaging intervals, no statistically significant differences were found in the mean values of CPET variables except for the ventilatory equivalent for carbon dioxide at the ventilatory anaerobic threshold (P = 0.001). No statistically significant differences were found in the proportion of patients classified as high or low risk regardless of the used data-averaging interval.ConclusionThere appears to be no significant or clinically relevant influence of the evaluated data-averaging intervals on the mean values of CPET outcomes used for preoperative risk assessment. Clinicians may choose a data-averaging interval that is appropriate for optimal interpretation and data visualization of the preoperative CPET. Nevertheless, caution should be taken as the chosen data-averaging interval might lead to substantial within-patient variation for individual patients.Clinical trial registrationProspectively registered at ClinicalTrials.gov (NCT05353127).

BackgroundAccurate determination of cardiopulmonary exercise test (CPET) derived parameters is essential to allow for uniform preoperative risk assessment. The objective of this prospective observational study was to evaluate the inter-observer agreement of preoperative CPET-derived variables by comparing a self-preferred approach with a systematic guideline-based approach.MethodsTwenty-six professionals from multiple centers across the Netherlands interpreted 12 preoperative CPETs of patients scheduled for hepatopancreatobiliary surgery. Outcome parameters of interest were oxygen uptake at the ventilatory anaerobic threshold (V̇O2VAT) and at peak exercise (V̇O2peak), the slope of the relationship between the minute ventilation and carbon dioxide production (V̇E/V̇CO2-slope), and the oxygen uptake efficiency slope (OUES). Inter-observer agreement of the self-preferred approach and the guideline-based approach was quantified by means of the intra-class correlation coefficient.ResultsAcross the complete cohort, inter-observer agreement intraclass correlation coefficient (ICC) was 0.76 (95% confidence interval (CI) 0.57–0.93) for V̇O2VAT, 0.98 (95% CI 0.95–0.99) for V̇O2peak, and 0.86 (95% CI 0.75–0.95) for the V̇E/V̇CO2-slope when using the self-preferred approach. By using a systematic guideline-based approach, ICCs were 0.88 (95% CI 0.74–0.97) for V̇O2VAT, 0.99 (95% CI 0.99–1.00) for V̇O2peak, 0.97 (95% CI 0.94–0.99) for the V̇E/V̇CO2-slope, and 0.98 (95% CI 0.96–0.99) for the OUES.ConclusionsInter-observer agreement of numerical values of CPET-derived parameters can be improved by using a systematic guideline-based approach. Effort-independent variables such as the V̇E/V̇CO2-slope and the OUES might be useful to further improve uniformity in preoperative risk assessment in addition to, or in case V̇O2VAT and V̇O2peak are not determinable.

What Maintains the Metabolic Cost at Maximal Exercise in Heart Transplant Recipients and Coronary Artery Disease Patients?

The aim was to evaluate the effects of digoxin, propranolol, and verapamil on exercise in patients with chronic isolated atrial fibrillation. Patients with chronic isolated atrial fibrillation underwent maximal exercise testing before and after the administration of digoxin, propranolol, or verapamil. Heart rate, oxygen uptake and oxygen pulse were observed at rest, at gas exchange anaerobic threshold, and at peak exercise. The subjects were 10 patients (aged 48-78 years, mean age 60, SD 9, years) with chronic isolated atrial fibrillation. During exercise without medication, the heart rate was 85 (SD 8) beats.min-1 at rest, 127(19) at the level of anaerobic threshold, and 175(17) at peak exercise. With digoxin, heart rate was reduced to 75(9) beats.min-1 at rest (control v digoxin, p less than 0.01). However, reduction of heart rate was not seen at anaerobic threshold or at peak exercise. With propranolol, heart rate was 63(7) beats.min-1 at rest, 99(16) at anaerobic threshold, and 138(28) at peak exercise (control v propranolol, all p less than 0.01). Heart rate with verapamil was 70(13) beats.min-1 at rest, 107(30) at anaerobic threshold, and 138(28) at peak exercise (control v verapamil, p less than 0.05 at rest and at anaerobic threshold, p less than 0.01 at peak exercise. Neither digoxin, nor propranolol, nor verapamil changed the oxygen uptake during exercise. Without medication, oxygen pulse was 6.5(2.0) ml.beat-1 at anaerobic threshold and 7.7(2.1) ml.beat-1 at peak exercise. With digoxin, the change of oxygen pulse, versus without medication, was not significant at rest or at anaerobic threshold but was increased at peak exercise, at 8.3(2.1) v 7.7(2.1) ml.beat-1, p less than 0.05. With propranolol, oxygen pulse was increased to 8.2(1.9) ml.beat-1 at anaerobic threshold and 9.2(2.3) ml.beat-1 at peak exercise (control v propranolol, both p less than 0.01). With verapamil, oxygen pulse was increased to 8.7(1.8) ml.beat-1 at anaerobic threshold and 10.0(2.1) ml.beat-1 at peak exercise (control v verapamil, both p less than 0.01). Digoxin was effective in reducing heart rate at rest, but failed to reduce it during exercise. Propranolol and verapamil reduced heart rate at all levels of exercise as well as at rest. Oxygen uptake during exercise (total exercise capacity) was not reduced with propranolol or verapamil; this was thought to have been accomplished by an increased oxygen pulse.

Comparison of the Peak Exercise Response Measured by the Ramp and 1-min Step Cycle Exercise Protocols in Patients With Exertional Dyspnea

Heart-Lung Interactions in HFpEF: Dynamic Hyperinflation and Exercise PCWP.

Determinants of Exercise Capacity in CKD Patients Treated With Hemodialysis

Application of risk assessment tools to predict opioid usage after shoulder surgery.

Introduction Exercise intolerance is a hallmark of heart failure with reduced ejection fraction (HFrEF) resulting from a variety of factors including comprised oxygen delivery. A common comorbidity of HFrEF is chronic obstructive pulmonary disease (COPD), which is independently associated with reduced exercise tolerance and cardiac output (Q) as well as peripheral dysfunction similar to HFrEF. It is currently unknown if HFrEF and coexisting COPD (HFrEF+COPD) exhibit worsened exercise tolerance and whether the mechanisms thereof are similar to HFrEF alone. We hypothesized that patients with HFrEF+COPD demonstrate further reductions in peak VO 2 and workload subsequent to a lower peak Q and arterio‐mixed venous O 2 content difference (C(a‐v)O 2 ) compared to HFrEF alone. Methods HFrEF+COPD (n=16) and HFrEF (n=17) (age: 57±7 vs 54±6 yrs; EF%: 20±5 vs 21±5; height: 173±7 vs 174±7 cm; weight: 88±14 vs 86±17 kg; all p>0.18) underwent peak exercise testing during right heart catheterization. At rest and peak exercise, invasive hemodynamic, cardiac pressures, and arterial pressures were performed. Heart rate and oxygen uptake (VO 2 ) were measured at rest and peak exercise via 12‐lead ECG and metabolic measurement system, respectively. Convective oxygen delivery was calculated as Q multiplied by CaO 2 . Results Peak exercise VO 2 and workload were lower in HFrEF+COPD compared to HFrEF (7.0±1.9 vs. 9.9±2.7 mL/min/kg; 34±7 vs. 45±12 watts; both p<0.01). At peak exercise, Q and stroke volume were lower in HFrEF+COPD than HFrEF (4.8±1.3 vs. 7.0±3.0 L/min; 52±16 vs. 75±28 mL; both p<0.01). Significant relationships existed between delta VO 2 and Q (peak exercise minus resting) in HFrEF+COPD and HFrEF (r=0.84 and r=0.89; both p<0.01); however, HFrEF+COPD had a significantly lower slope (p=0.02). Peak exercise C(a‐v)O 2 was not different between HFrEF+COPD and HFrEF (12.9±2.3 vs. 12.8±2.6 mL/dL; p=0.89). No differences were present in heart rate or hemoglobin at peak exercise (p>0.73). Delta VO 2 and C(a‐v)O 2 was significantly related for HFrEF+COPD (r=0.68; p<0.01), but not HFrEF (r=0.14, p=0.57). At peak exercise, HFrEF+COPD had lower convective oxygen delivery (845±239 vs. 1230±517 mL/min; p<0.01). Conclusions Patients with HFrEF and concurrent COPD demonstrate worsened exercise tolerance compared to HFrEF resulting from reduced oxygen delivery. These data suggest HFrEF with COPD exhibit more severe central and peripheral abnormalities than HFrEF alone. Support or Funding Information NHLBI RO1 HL126638 This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .

Exercise testing in aortic regurgitation: Comparison of radionuclide left ventricular ejection fraction with exercise performance at the anaerobic threshold and peak exercise

Aims Formal preoperative assessment of risk of complications and death in all patients undergoing Emergency Laparotomy is recommended by NELA (National Emergency Laparotomy Audit) in the UK. In addition, frailty assessment in patients who are 65years or older and frail undergoing Emergency Laparotomy is also recommended. In a previous 2018 audit, we had recorded Preoperative Mortality Risk in 77% patients undergoing Emergency Laparotomy and Frailty was not part of our assessment in these patients. In this audit our aim was to evaluate documentation of preoperative frailty and risk assessment in patients undergoing Emergency Laparotomy from 2019 to 2023. Methods Details of all patients who underwent Emergency Laparotomy at a University Hospital under care of one surgical team between January 2019 and December 2023 were obtained from theatre logbooks. Patient notes were retrospectively reviewed to see if frailty assessment and preoperative risk assessment scores were recorded. This data was collected and analyzed using Microsoft Excel. Results During this period, sixty-seven patients were identified. The median age was sixty-seven with an age range from four to ninety-one. Of these 38 (57%) were females. A preoperative p-possum score was documented in 59 (88.1%), 39 (58.2%) patients were 65 years or older of these 26 (66.7%) had frailty assessment carried out. Conclusions Our data suggests that we have over time made progress in the use of Perioperative Risk assessment scores and incorporated frailty assessment in our perioperative practice in patient’s undergoing Emergency Laparotomy. However there remains room for improvement.