During general anesthesia, the administration of anesthetics and muscle relaxants induces apnea, wherein spontaneous breathing ceases . Pediatric patients, characterized by their higher oxygen consumption rate and smaller functional residual capacity, are particularly susceptible to hypoxemia during apneic episodes . This vulnerability to hypoxemia underscores the critical need for effective oxygenation strategies during anesthesia. Apneic oxygenation, the provision of oxygen without concurrent tidal volume delivery, emerges as a vital technique in pediatric anesthesia, playing a pivotal role in both routine and challenging airway management scenarios .

In modern practice, apneic oxygenation during airway management denotes the uninterrupted supply of oxygen, extending the window for maintaining safe oxygen saturation levels during the apneic phase . This technique holds particular significance in pediatric patients undergoing adenotonsillectomy, where the delicate balance of oxygenation is paramount .

Adenotonsillectomy, a common surgical procedure in pediatric patients, poses unique challenges in airway management . The procedure involves the removal of the adenoids and tonsils, often necessitating general anesthesia and temporary airway obstruction . Furthermore, the potential for blood and secretions in the oropharynx increases the risk of airway compromise during the perioperative period. In this context, ensuring adequate oxygenation is essential to mitigate the risk of hypoxemia and its associated complications In this randomized clinical trial, the investigators aim to evaluate the efficacy and safety of apneic oxygenation using nasal cannula in pediatric patients undergoing adenotonsillectomy under general anesthesia. By assessing our primary outcome and secondary outcomes, the investigators seek to contribute valuable insights into optimizing anesthesia management protocols for this vulnerable patient population.

Following permission from the local institutional review board and institutional ethics committee, this study will be carried out at the FAYOUM University hospital. The research will employ a single -blinded, randomized, and controlled approach.

Prior to recruitment and randomization, detailed consent will be obtained from the parents or legal guardians of eligible patients.

Patients were randomly allocated 1: 1 to the two study groups:

Group (A):

Patients in the group A will undergo tracheal intubation without apneic oxygenation

Group (B):

Patients in the group B will undergo tracheal intubation in addition to apneic oxygenation at a flow 0.2 mg/kg using nasal cannula The randomization will be computer generated random number and the randomization sequence will be kept hidden in sealed opaque envelopes just opened after recruitment and admittance to the operating room. The group's allocations will be only blinded to parents of children.

In both the control and experimental groups, subjects will undergo a standardized general anesthesia protocol. All pediatric participants will receive premedication in the form of 0.5 mg/kg rectal midazolam upon admission to the operating theater, patients will be comfortably positioned on the operating table. Standard monitoring devices, including electrocardiography (ECG), non-invasive blood pressure (NIBP) measurement, pulse oximetry, and end-tidal carbon dioxide (EtCO2) monitoring, will be affixed. Intravenous access will be established to facilitate fluid and medication administration. In instances where venous access proves challenging, patients will be induced with inhaled sevoflurane at 8% concentration, followed by the insertion of an intravenous cannula. Subsequently, anesthetic induction will be achieved using a combination of 2 - 3 mg/kg of Propofol, 1 mcg/kg of Fentanyl, and 0.5 mg/kg of Atracurium. Following induction, bag-mask ventilation with 100% oxygen and flow rates of 6-8 litres min will be initiated for 3 minutes Ventilation will then be discontinued. In the apneic oxygenation group, nasal cannula will be employed to administer continuous oxygenation, utilizing a flow rate of 0.2 L/kg, during the apneic phase while tracheal intubation is performed. Successful intubation will be confirmed by auscultation and the appearance of a square wave capnogragh.

Following intubation, SpO2 levels will be recorded, and mechanical ventilation will be instituted to maintain normocapnia and oxygenation within predetermined target ranges.

In case of desaturation, the procedure will be discontinued as soon as the SpO2 reach 92%. Bag mask ventilation with 100% oxygen will be started until spo2 reach 100%, Intubation will then be performed by the supervising consultant anesthesiologist

Inclusion Criteria:

• Patients (3 - 10 Years).
• Patients who were scheduled for adenotonsillectomy.
• ASA I and II

Exclusion Criteria:

• When nasal intubation is needed.
• Patients reported with nasal obstruction.
• Patients with any respiratory disease like asthma or recent upper respiratory tract infection.
• Patients with obstructive sleep apnea
• Patients with congenital heart disease
• Patients suspected difficult intubation or syndromatic patients eg : down syndrome , Goldenhar Syndrome , Pierre Robin syndrome … etc