What can we learn from sarcopenia with curarisation in the context of cancer surgery? A review of the literature

Introduction: The monitoring of the curarisation is a unique opportunity to investigate the function of the neuromuscular junction (NMJ) during cancer surgery, especially in frailty-induced and age-related sarcopenia. Method: We conducted a comprehensive literature review in PubMed, without any limit of time related to frailty, sarcopenia, age and response to neuromuscular blockers in the context of cancer surgery. Results: Several modifications appear with age: changes in cardiac output, a decrease in muscle mass and increase in body fat, the deterioration in renal and hepatic function, the plasma clearance and the volume of distribution in elderly are smaller. These changes can be exacerbated in cancer patients. We also find modifications of the NMJ: dysfunctional mitochondria, modifications in the innervation of muscle fibers and motor units, uncoupling of the excitation-contraction of muscle fibers, inflammation. Neuromuscular blocking agents (NMBAs) compete with acetylcholine and prevent it from fixing itself on its receptor. Many publications reported guidelines for using NMBAs in the elderly, based on studies comparing old people with young people. No one screened frailty before, and thus, no studies compared frail elderly and non-frail elderly undergoing cancer surgery. Conclusion: Despite many studies about curarisation in the specific populations, and many arguments for a potential interest for investigation, no studies investigated specifically the response to NMBAs in regard of the frailty-induced and age-related sarcopenia.