Assessing functional capacity before surgery
Addressing the lack of consensus
Functional capacity, a strong prognostic indicator, can help identify patients at heightened risk of complications following surgery. However, the lack of consensus on appropriate clinical tools for assessing functional capacity poses a challenge.
The importance of functional capacity assessment
Functional capacity, also referred to as cardiopulmonary fitness or cardiorespiratory fitness, gauges an individual's ability to perform sustained aerobic activities by optimising oxygen delivery to tissues. It is a cornerstone in risk assessment before non-cardiac surgery, as it assists medical practitioners in making informed decisions and optimising patient care before surgical procedures. This assessment is formally quantified as oxygen consumption during exercise at maximal effort, often expressed as metabolic equivalents of task (METs).
Functional capacity assessment has proved valuable in various medical contexts, such as predicting outcomes post-acute myocardial infarction, guiding therapy for heart failure patients, and distinguishing between cardiac and pulmonary causes of exertional dyspnea. In perioperative settings, it serves as a prognostic tool, aiding shared decision-making and preoperative optimisation.
Challenges in functional capacity assessment
Several methods to measure functional capacity exist, including cardiopulmonary exercise testing (CPET), the 6-minute walk test, and questionnaires like the Duke Activity Status Index. However, applying these methods to a surgical population presents challenges. CPET requires incremental exercise performance on a bicycle or treadmill, which can be difficult for patients with surgical-related functional limitations unrelated to cardiopulmonary fitness. Patient-reported questionnaires offer an alternative, indirectly assessing functional capacity with reasonable accuracy. However, these tools may inadequately capture sedentary individuals or those with non-cardiorespiratory restrictions. This oversight could perpetuate disparities in perioperative outcomes for vulnerable populations.
Scoping review
A scoping review is underway to consolidate existing knowledge on functional capacity assessment tools for adults undergoing elective non-cardiac surgery. The review aims to summarise the tools available, assess the depth of investigation supporting each tool, and identify gaps in their development. Moreover, the review will focus on the extent of validation for each tool, especially in populations with physical limitations that might influence the accuracy of functional capacity assessments. This includes those that depend on physical performance.
The protocol for the Scoping review is available in the August issue of JBI Evidence Synthesis
Daza, Julian F.; Chesney, Tyler R.; Alibhai, Shabbir M.H.; Kennedy, Erin D.; Lebovic, Gerald; Lightfoot, David; Mbadjeu Hondjeu, Arnaud R.; Morales, Juan F.; Pivetta, Bianca; Jolley, Rachel; Racz, Elizabeth; Wilmshurst, Luke; Wijeysundera, Duminda N.
JBI Evidence Synthesis 21(8):p 1632-1647, August 2023. | DOI: 10.11124/JBIES-22-00397