Diaphragmatic function in Anesthesia and Intensive Care Unit: Role of ultrasonography in assessing postoperative residual curarization

The extensive use of neuromuscular blocking agents (NMBAs) during surgical procedures has increased the concern of residual paralyzing effect in the post-operative period. In order to avoid residual effects neuromuscular monitoring is advocated in intra-operative setting to improve patient safety. For many years Acetyl Cholinesterase inhibitors (AChEi), has been used to reverse muscle block but their short half-life can cause a partial recurarization in ward setting especially if intermediate-long acting agents are administered. Sugammadex is the first selective reversal drug for steroidal neuromuscular blocking agents, and it has been proved to give full and rapid recovery of muscle strength, thus minimizing the occurrence of residual curarization. Acceleromyography of the adductor of pollicis is the gold standard to detect residual curarization but is not affordable in awake patients. Diaphragm is the major respiratory muscle and its dysfunction is associated with the occurrence of respiratory failure. Introduction of ultrasonography made studying the diaphragm thickness more reliable and a good tool individuate residual effect of NMBAs in awake patients.