The use of neuromuscular blockers (NMB) is essential to optimize surgical conditions, ensure patient immobility during the intervention and prevent complications derived from involuntary movements. Intraoperative monitoring of neuromuscular relaxation allows the depth of neuromuscular blockade to be accurately evaluated, guaranteeing ideal conditions for the surgical team. Residual neuromuscular blockade (RNMB) is the persistence of muscle paralysis after the administration of NMB during a surgical intervention. The appearance of RNMB poses substantial challenges in the postoperative period, as it has negative repercussions for the safety and well-being of the patient.

The use of neuromuscular blockers (NMB) is essential to optimize surgical conditions, ensure patient immobility during the intervention and prevent complications derived from involuntary movements. Intraoperative monitoring of neuromuscular relaxation allows the depth of neuromuscular blockade to be accurately evaluated, guaranteeing ideal conditions for the surgical team. Residual neuromuscular blockade (RNMB) is the persistence of muscle paralysis after the administration of NMB during a surgical intervention. The appearance of RNMB poses substantial challenges in the postoperative period, as it has negative repercussions for the safety and well-being of the patient. In this prospective observational study, all patients who underwent general anesthesia with neuromuscular blockade were studied consecutively to evaluate the presence of residual neuromuscular blockade and its potential consequences during hospital admission.Considering that the percentage of residual curarization is 19% (PORCzero study), with a 95% confidence interval and a 3% error margin, 236 patients are needed to accurately estimate the prevalence of residual curarization in the study population. With an expected loss proportion of 20%, the chosen sample size is 296 patients.

Inclusion Criteria:

• Patient undergoing surgical intervention under general anesthesia that requires the use of neuromuscular block during the study time and that required hospital admission.
• Informed consent signature.

Exclusion Criteria:

• Neuromuscular disease
• Not having received neuromuscular block during the intervention
• Admission to the outpatient surgery unit
• Admission to the postoperative intensive care unit
• Patients who signed informed consent, but postoperative data could not be collected upon arrival at the PACU.

Patients undergoing surgical intervention under general anesthesia that requires the use of neuromuscular block during the study time.