Manual Valsalva Maneuver As a Preventive Measure of Postoperative Laryngospasm in Laryngomalacia Cases Undergoing Supraglottoplasty

Congenital Laryngomalacia is the main cause of stridor in newborns and infants, affecting 45-75% of all infants with congenital stridor. Short aryepiglottic folds, redundant arytenoid, omega-shaped epiglottis, and inspiratory stridor are features of laryngomalacia. Pediatric laryngospasm is a glottic closure due to reflex constriction of the laryngeal muscles that produce partial or complete obstruction of the larynx. When complete and sustained, laryngospasm is considered an anesthetic Emergency.

The valsalva maneuver involves expiratory effort against a closed glottis in the sitting or supine position with the intraoral and intrathoracic pressures raised to 40 mmHg for 15-20 sec, after which the pressure is suddenly released and the breathing restored to normal.

We hypothesized that manual valsalva maneuver prevent incidence of postoperative laryngospasm after supraglottoplasty for cases of congenital laryngomalacia.

After approval of IRB, Mansoura University, this study will be conducted on infants and children ASA I or II aging from 1 month age- 6 years undergoing supraglottoplasty in Mansoura university hospitals. After obtaining a written informed consent from patients parents, random number generator with closed envelope technique will randomize patients into two groups \[control\] group ( C group ), Valsalva group ( V group)\].

Anesthesia will be induced by inhalational induction using sevoflurane at concentration (6:8%). After that, a proper sized cannula will be introduced with giving atropine 0,01mg/kg and hydrocortisone 4mg/ kg. Then, patients will be seen by fiberoptic endoscopy by the surgeon to detect the stage of laryngomalacia and the supraglottic pathology. After that, proper sized ETT will be inserted using succinylcholine 1mg\\kg IV and fixed in place after confirmation of correct positioning , with maintenance of anesthesia with isoflurane. All patients will be given 0.5-1mic /kg fentanyl and 15 mg /kg paracetamol.

A pilot study will be done including 5 patients in each study group. The Incidence of postoperative stridor will be used as the primary variable with difference between studied groups was 40% (50% in group C versus 10% in group V). G\*power software version 3.1.9.2 will be utilized to detect the required sample size for a study power of 90% and alpha error of 0.05. Cases involved in the pilot study will not be included in the total sample size of the study. Then total sample size will be 26 in each group and by adding 10% to compensate for possible drop out then total sample size per group will be 29 cases in each group. Perioperative data will be tabulated and analyzed using IBM SPSS software version 26.

• incidence of reintubation [Time frame: 24 HOURS]
• Postoperative oxygen saturation measurement [Time frame: 1 HOUR]
• Incidence of postoperative nausea and vomiting [Time frame: 24 HOURS]
• Duration of postoperative hospital stay [Time frame: 24 HOURS]