The aim of this study is to investigate the effect of addition of intranasal ketamine to midazolam compared to midazolam alone as a premedication on the occurrence of PRAEs

Perioperative respiratory adverse events (PRAEs) are the most common complication during pediatric anesthesia furthermore, most children presenting for AT have sleep-disordered breathing and obstructive sleep apnea syndrome (OSAS) caused by tonsillar hypertrophy which could aggravate the PRAEs specially with the use of the conventional sedatives as a premedication. A recent randomized controlled trial has shown that more than 50% of children premedicated with midazolam had experienced PRAEs . Midazolam and ketamine are commonly used as preoperative sedative drugs for pediatric populations. Ketamine is a safe and widely used sedative and analgesic in the pediatric emergency department (ED) with less profound effects on the upper airway and respiratory muscles. Intranasal ketamine administration is well tolerated and without serious adverse effects. The addition of ketamine to midazolam as a preoperative sedation to reduce the occurrence of PRAEs was not investigated before in children undergoing AT. The authors hypothesize that combination of ketamine to midazolam could offer optimum sedation condition while reducing the occurrence of PRAEs in children undergoing AT.

Inclusion Criteria:

• Children both sexes male and female.
• Age from 3 to 12 years old.
• ASA grade I, II.
• undergoing elective AT procedures.

Exclusion Criteria:

• Congenital heart diseases (cyanotic and a cyanotic).
• Congenital syndromes affecting airway anatomy such as Pierre-Robin syndrome and Down syndrome.
• Severe lung diseases affecting either lung tissue such as pulmonary cystic fibrosis and idiopathic pulmonary fibrosis or affecting lung circulation such as pulmonary hypertension with marked limitation of Physical activity or inability to carry out any physical activity according to NHYA classification.
• Recent upper respiratory tract infection (less than two weeks).
• Neuromuscular diseases including cerebral palsy and epilepsy.

The drug will be prepared by an anesthesia nurse who will not be involved in the study. The active drug will be administered by a fully trained anesthesiologist and Clear definitions of the respiratory adverse events will be provided to the involved anesthetist. All researchers directly involved in the study will be blinded to the drug which will be administered