Background and Goal of Study: Respiratory adverse events represent a major cause of perioperative morbidity, in children. The aim of this study was to determine the incidence of and risk factors for PRAE in children undergoing elective surgical procedures under general anesthesia.
Materials and Methods: It´s a prospective observational study, including children undergoing general anesthesia for elective surgical procedures in pediatric anesthesiology department from November 2014 to November 2016. We collected demographic data, medical history of asthma, allergy, second hand smoking, night-snoring and sleep apnea and recent upper respiratory tract infection. Induction techniques and agents, airway management and the occurrence of PRAE (moment, management strategy and evolution) were recorded. Pearson´s Chi-square and Fisher´s exact tests were used. P < 0.05 was considered significant. Multivariate Cox regression was employed to identify independent predictors for PRAE.
Results and Discussion: 1022 children were included in the study. PRAE occurred in 96 (9,4%) patients. Laryngospasm, bronchospasm, desaturation, upper airway obstruction and coughing occured in 7 (7,4%), 36 (37,5%), 18 (18,7%), 18 (18,7%) and 17 (17,7%), respectively. The incidence of PRAE was higher at the emergence period (61; 63,5%) compared to the induction (19; 19,8%) and the maintenance (16; 16,7%) of anesthesia. Children under 12 month-old, ASA (American Society of Anesthesiologist) class superior to 1, upper respiratory tract infection, night snore, use of laryngeal mask airways and endotracheal intubation were independently associated with a higher risk of PRAE; with an Odds-Ratio equal to 2,41 (95% CI [1,29-4,50] ; p=0,005), 2,89 (95% CI [1,01-8,27] ; p=0,047), 2,22 (95% CI [1,36-3,61] ; p=0,001), 1,78 (95% CI [1,00-3,17] ; p=0,047), 2,44 (95% CI [1,18-5,05] ; p=0,016) and 2,67 (95% CI [1,25-5,71] ; p=0,011) Respectively. Factors that were independently associated with lower incidence of PRAE were management of peripheral regional nerve block (OR=0,51 95% CI [0,30-0,88] ; p=0,015) and inhalatory induction (OR=0,47 95% CI [0,25-0,87] ; p=0,018 ). Asthma and second hand smoking were not associated with a higher risk of PRAE in our cohort.
Conclusion(s): PRAE occur more often in the emergence period. Age under 3 and a recent history of upper airway tract infection are the main predictive factors of PRAE in our study.

Incidence of and Risk factors for perioperative respiratory adverse events in children: a prospective cohort study