CPET is the gold standard for objective, quantitative assessment of cardio-respiratory fitness. However, it is resource consuming in terms of cost and time for patients and institutions, and impossible to perform or contraindicated in some patients. The most commonly used variables for perioperative risk stratification are the anaerobic threshold (AT) and peak oxygen delivery (VO2 peak).
Resources | Hand grip strength (HGS) is only weakly related to CPET variables in preoperative patients
Hand grip strength (HGS) is only weakly related to CPET variables in preoperative patients
J. Hilton R. Laza-Cagigas D. Sumner T. Rampal
HGS is rapid, inexpensive and requires minimal training or equipment to undertake reproducibly. Impaired HGS has been shown to be associated with increased post operative mortality, morbidity and length of stay across various surgical specialities. We sought to establish whether HGS is related to variables derived from CPET at our institution
Methods
The study population consisted of a retrospective analysis of 95 patients presenting to the prehabilitation unit of a district general hospital in the UK undergoing CPET prior to surgery between August 2018 and May 2019. Resting HGS was measured using an analogue grip dynamometer (Grip-A, Takei Scientific). The maximum grip strength achieved bilaterally was used for analysis. CPET
was undertaken using a cycle ergometer (Ergostik, Lovemedical) according to a ramp protocol and analysis performed using Blue Cherry (Geratherm Respiratory). Statistical analysis of correlation was performed using the Pearson coefficient (r) and significance using a 2-sided test using Microsoft Excel for mac v16.
Results
In this group of patients AT and peak VO2 were only weakly related to HGS. This is perhaps surprising given previous findings suggesting that HGS is associated with loss of physical function. This negative finding may be due to inadequate sample size, effort dependence of VO2 peak, poor correlation between upper and lower limb muscle mass (CPET at our centre is performed on a cycle).
Strengths of this study include standardised testing, a range of age, sex and surgical specialities. Weaknesses are that no patient centred or clinical endpoints were investigated, and potential bias due to selective referrals and retrospective nature of the study.
These results reinforce that there is unlikely to be any universally applicable, reliable test to inform perioperative risk, as concordance of different markers of ‘fitness’ is limited. Hand grip strength, however, may be useful in combination with CPET to help guide personalised, shared decision making.
References
Sultan P, Hamilton MA, Ackland GL. Preoperative muscle weakness as defined by handgrip strength and postoperative outcomes: a systematic review. BMC Anesthesiology 2012; 12:1 Levett, D, Jack, S, Swart, M, et al. Perioperative cardiopulmonary exercise testing (CPET): Consensus clinical guidelines on indications, organization, conduct, and physiological interpretation. BJA 2018; 120(3): 484-500
