Comparison of Dynamic Compliance and Airway Resistance in Pressure Versus Volume Controlled Ventilation Among Pediatric Patients With Left to Right Intra-Cardiac Shunt Undergoing Corrective Surgery
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 72
- 试验地点
- 1
- 主要终点
- Airway resistance
研究概览
简要总结
The goal of this clinical trial was to compare two settings on a breathing machine used during heart surgery in children.
The children in this study were born with a hole inside the heart. The hole lets extra blood flow to the lungs. Over time this can make the lungs stiffer and harder to inflate. All the children had surgery to close the hole, using a heart-lung machine.
During surgery, a machine breathes for the child. It can be set in two ways. One way controls the pressure of each breath. The other way controls the amount of air in each breath.
The main questions it aimed to answer were:
Which setting kept the lungs easier to inflate during and after surgery? Which setting made it easier for air to move through the breathing tubes? Researchers compared children who got pressure-controlled ventilation with children who got volume-controlled ventilation, to see if lung function differed between the two groups.
Participants:
Had surgery to close the hole in the heart Got one of the two breathing machine settings, chosen at random Had lung measurements taken at eight points, from just after the breathing tube was placed until they were ready to come off the machine.
详细描述
Children with acyanotic left-to-right intracardiac shunt lesions (atrial septal defect or ventricular septal defect) with raised pulmonary artery pressure underwent corrective surgery on cardiopulmonary bypass and were allocated to pressure-controlled or volume-controlled ventilation.
Allocation used pair matching on age, sex and lesion type. One member of each matched pair was assigned by concealed coin toss, and the other was assigned to the alternate group.
Sample size was calculated from the expected difference in mean airway resistance between ventilation modes reported by Tan et al., assuming a standard deviation of 5.82, a between-group difference of 3.9, 5% type I error and 80% power, giving 35 participants per group. Two additional participants were enrolled to allow for protocol deviations or incomplete datasets, giving 36 per group.
Anaesthesia was delivered by a single experienced paediatric cardiac anaesthesiologist so that protocol execution stayed uniform. All intraoperative and postoperative data were recorded by an independent observer blinded to allocation, and analysis used anonymised datasets. The anaesthesiologist managing ventilation could not be blinded to allocation.
Ventilation was standardised across both groups: target tidal volume 6-8 mL/kg, end-tidal carbon dioxide maintained at 35-45 mmHg, positive end-expiratory pressure 4-5 cm H2O, and an inspiratory-to-expiratory ratio of 1:2. Respiratory rate was adjusted to maintain normocapnia and fraction of inspired oxygen was guided by oxygenation status. In the volume-controlled group, tidal volume was set at 6-8 mL/kg. In the pressure-controlled group, inspiratory pressure was titrated to achieve the same tidal volume while keeping peak inspiratory pressure at or below 30 cm H2O.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Single (Outcomes Assessor)
盲法说明
Intraoperative and postoperative data were recorded by an independent observer blinded to group allocation, and analysis used anonymised datasets. The anaesthesiologist managing ventilation could not be blinded, since ventilator settings are visible during use.
入排标准
- 年龄范围
- 1 Month 至 18 Years（Child, Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Paediatric patients aged 1 month to 18 years
- •Left-to-right intracardiac shunt lesions (atrial septal defect or ventricular septal defect) undergoing corrective surgery under cardiopulmonary bypass - Elevated pulmonary artery pressure: pulmonary artery systolic pressure 30 mmHg or above, and/or mean pulmonary artery pressure 20 mmHg or above
排除标准
- •Refusal to participate
- •Presence of any other associated cardiac anomaly
- •Allergy to milrinone
- •Associated coagulation disorder
- •Neurological disorder
- •Hepatic or renal dysfunction
- •Failure to wean from cardiopulmonary bypass
研究组 & 干预措施
Group P - Pressure Controlled Ventilation
Inspiratory pressure titrated to achieve a tidal volume of 6-8 mL/kg while keeping peak inspiratory pressure at or below 30 cm H2O, with an inspiratory-to-expiratory ratio of 1:2 and respiratory rate adjusted to maintain end-tidal carbon dioxide at 35-45 mmHg.
干预措施: Pressure Controlled Ventilation (Other)
Group V - Volume Controlled Ventilation
Tidal volume set at 6-8 mL/kg, with an inspiratory-to-expiratory ratio of 1:2 and respiratory rate adjusted to maintain end-tidal carbon dioxide at 35-45 mmHg.
干预措施: Volume Controlled Ventilation (Other)
结局指标
主要结局
Airway resistance
时间窗: Eight perioperative timepoints: immediate post-intubation, ten minutes post-intubation, pre-sternotomy, pre-bypass, immediate post-bypass, five minutes after protamine administration, post-sternal closure, and pre-weaning from mechanical ventilation
Airway resistance derived from ventilator measurements, expressed in cm H2O/L/second
Dynamic compliance
时间窗: Eight perioperative timepoints: immediate post-intubation, ten minutes post-intubation, pre-sternotomy, pre-bypass, immediate post-bypass, five minutes after protamine administration, post-sternal closure, and pre-weaning from mechanical ventilation
Dynamic respiratory system compliance derived from ventilator measurements, expressed in mL/cm H2O
PaO2/FiO2 ratio
时间窗: Eight perioperative timepoints: immediate post-intubation, ten minutes post-intubation, pre-sternotomy, pre-bypass, immediate post-bypass, five minutes after protamine administration, post-sternal closure, and pre-weaning from mechanical ventilation
Ratio of arterial partial pressure of oxygen to fraction of inspired oxygen, calculated from arterial blood gas analysis, expressed in mmHg
次要结局
- Mean Airway Pressure(Eight perioperative timepoints: immediate post-intubation, ten minutes post-intubation, pre-sternotomy, pre-bypass, immediate post-bypass, five minutes after protamine administration, post-sternal closure, and pre-weaning from mechanical ventilation)
研究者
Prateek Purkayastha
DM Post-doctoral Trainee, Department of Cardiac Anaesthesia
Nilratan Sircar Medical College