Residual neuromuscular blockade (RNB) is frequent and it is associated with negative impact on postoperative morbidity and mortality. The incidence of the RNB in adult is well described, however in pediatric subpopulation it is currently not known. The aim of this prospective observational cohort study is to evaluate the early RNB just before extubation and late RNB at the time of arrival to postanesthetic care unit (PACU). In the trial will be enrolled all pediatric patients (28 weeks of age and older - 19 years old) whom will be administered neuromuscular blocking agent during anesthesia. The demographic data will be collected including: age, weight, type of surgery, ASA status. The anesthesia management will be described including: airway management, type and cumulative dose of neuromuscular blocking agent (NMBA) and time and dose of the last administered bolus of NMBA. The residual neuromuscular blockade will be measured according to the standards: TOF Watch accelerometry at the moment prior to extubation (two measurements) in TOF mode and at the arrival to postanesthetic care unit (PACU) (two measurements) in TOF mode.