Nasal Decongestant to Reduce Perioperative Adverse Events in Children With Upper Respiratory Track Infections Having Anesthesia.

The goal of this multicentre, double-blind, randomised controlled trial study is to learn if the use of a nasal spray to open the nasal passages and increase airflow before surgery can reduce the occurrence of perioperative respiratory adverse events in children with upper respiratory tract infection who are undergoing anesthesia. The main questions it aims to answer are: * Does use of a nasal decongestant (Oxymetazoline 0.05%) reduce perioperative respiratory adverse events during emergence (when waking up from anesthesia) or in the post-anesthesia care unit in children. * Is it easy and acceptable to doctors, children and parents to use the nasal decongestant treatment? Researchers will compare the nasal decongestant to a placebo (a look-alike substance that contains no drug) to see if it works to reduce perioperative respiratory adverse effects. Participants will: * Take a nasal decongestant or a placebo prior to surgery (just before anaesthesia is given) * Be monitored during and after surgery in the post-anaesthesia care unit for any perioperative respiratory adverse events. * Be asked about how acceptable they found the treatment.