Efficacy of Recruitment Maneuver in Pediatric Patients Under General Anesthesia

Study Overview
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Brief Summary
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During general anesthesia lung collapses and atelectasis occurs. Preservation of atelectasis can cause pulmonary disfunction. The goal of safe anesthesia is to protect the lungs intraoperatively. Positive end-expiratory pressure (PEEP) is distending pressure that prevents alveolar collapse during mechanical ventilation and is a part of recruitment maneuver that is often used in patients on mechanical ventilation. Overall effect of PEEP is improvement in lung function. PEEP can have adverse effects on hemodynamics. The objective of this study was to assess the effect of step up and down PEEP titration on lung function and hemodynamics in healthy preschool children during general anesthesia. One group of children was ventilated with constant PEEP. the other was submitted to PEEP titration. Changes in lung compliance, gas exchange and hemodynamic status were documented as well as any unwanted effects.

Detailed Description
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Seventy preschool children American Society of Anesthesiologists classification system (ASA) I and II scheduled for non-cardiothoracic surgery were allocated in two groups. Interventional group (n=35) received PEEP titration and Control group (n=35) didn't. They were ventilated only with PEEP 3. PEEP titration: In Intervention group, 20 minutes before the end of anesthesia PEEP was increased by 2 on every 5 breaths to 11. Ventilation with PEEP 11 was maintained for 2 minutes. Then PEEP was reduced by 2 on every 5 breaths to 5 and remain as until awakening. Total time to perform titration was 5 minutes. Blood was collected in both groups, in equal points of time that is: after induction, 20 minutes before the end of surgery and after the end of surgery (20th minute). Investigators tested differences of outcome variables between groups and within the Interventional group before and after PEEP titration. Hemodynamic monitoring and monitoring of lung function were conducted in Interventional group to observe changes during PEEP titration.

Official Title
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The Assessment of Efficacy and Safety of Step-wise up and Down PEEP Titration in Healthy Pediatric Patients Under General Anesthesia

Conditions
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Healthy

Intervention / Treatment
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* Procedure: increase and decrease positive end-expiratory pressure


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age 3-7; ASA I and II absence of cardiovascular and respiratory comorbidity Exclusion criteria: current or recent (up to 4 weeks) upper airway infection present of gastroesophageal reflux allergic reactions to anesthetics contraindication to chosen anesthetics

Ages Eligible for Study
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Minimum Age: 3 Years
Maximum Age: 7 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: randomized parallel controlled clinical trial
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intervention group<br>Intervention: increase and decrease positive end-expiratory pressure. PEEP titration: 20 minutes before the end of anesthesia and surgery PEEP was increased by 2 on every 5 breaths to 11 ventilation was maintained on PEEP 11 for 2 minutes.Then, PEEP was reduced by 2 for every 5 breaths to 5.Total time to titrate was 5 minutes. | Procedure: increase and decrease positive end-expiratory pressure<br>* 20 minutes before the end of anesthesia and surgery PEEP was increased by 2 on every 5 breaths to 11. Ventilation with PEEP 11 was maintained for 2 minutes. Then, PEEP was reduced by 2 on every 5 breaths to 5 cmH2O<br>* Other names: ventilation with PEEP 3;|
| No Intervention: Control<br>Ventilation with PEEP 3 during anesthesia and surgery | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Partial pressure of oxygen | measured partial pressure of oxygen in arterial blood at the end of surgery in Interventional and Control group. | 10 minutes after PEEP titration | 
| Partial pressure of carbon dioxide | measured partial pressure carbon dioxide in arterial blood at the end of surgery in Interventional and in Control group | 10 minutes after PEEP titration | 
| Lung compliance | spirometric measurement of dynamic lung compliance at the end of surgery in Interventional and Control group | 10 minutes after PEEP titration | 
| Lung compliance | spirometric measurement of dynamic lung compliance on different PEEP levels in Interventional group | 5 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| postoperative hemoglobin oxygen saturation | hemoglobin oxygen saturation measured with puls oximeter | 4 hours after extubation | 
| intraoperative hemodynamic status | invasive blood pressure monitoring during PEEP titration in Interventional group | 5 minutes | 
| intraoperative respiratory adverse effect | airway pressure monitoring during PEEP titration in Interventional group | 5 minutes |