Twenty-four critically ill pediatric patients admitted from March 2007 to September 2007 were chosen for the present study. All patients selleck chemicals JQ1 were mechanically ventilated and had been followed to select cases of late-onset VAP (after the first 72 hours of mechanical ventilation) by broncho-alveolar lavage (BAL) cultures at end of third, fifth and seventh day of mechanical ventilation. Moreover, if the Clinical Pulmonary Infection Score (CPIS) was found to be above 6 at any time, additional BAL culture was considered. All patients were mechanically ventilated on pressure mode Pressure-Synchronized Intermittent Mandatory Ventilation (P-SIMV) and Continuous Positive Airway Pressure with Pressure support (CPAP with PS) using non-cuffed Polyvinyl endotraceal tubes.

Patients with evidence of pneumonia at the time of mechanical ventilation, patients on antacids, H2 blockers or proton pump inhibitors were excluded from the study. All patients were nutritionally supported through total parenteral nutrition during the study period and use of nasogastric tube feeding was an exclusion criterion.The study protocol was approved by the ethical committee of the Pediatrics Department, Ain Shams Faculty of Medicine in December 2006. Informed written consent was given by the parents/caregivers of all patients. When parents/caregivers were illiterate, the consent was read to them by a hospital social worker who was not involved in the study, and the consent form was witnessed by an independent third party.

A full medical history was taken from all patients which included name, age, sex, date, and cause of PICU admission, duration of PICU stay, setting of mechanical ventilation, history of medications, type of nutrition and the fate of all patients. Full clinical examination and estimation of the angle of back rest elevation was performed for all subjects. Evaluation was performed through applying the ‘pediatric risk of mortality score’ (PRISM II) [7] at the time of admission.All subjects were studied with esophageal 24 hours pH-metry using Quick Start Orion II pH monitor MMS (Medical Measurement Systems Company, Enschede, The Netherlands) using a single-use, one-way catheter. The study has been performed within the first 24 hours from starting mechanical ventilation and after hemodynamic stabilization of the patient.

The catheter was calibrated before use with two solutions, one acidic (pH = 4) and the other alkaline (pH = 7). The catheter was inserted in the lower esophagus 5 cm above the gastro-esophageal Dacomitinib sphincter (as detected by a plain film), and then the pH was recorded in 24 hours. The pH monitor recorded the reflux either acidic or alkaline through recording the pH, total reflux time, number of reflux episodes, and longest reflux [8]. The reflux was considered pathological when the total reflux time exceeds 4% of total recording time [9].Statistical methodsAll data were tabulated.