Plasma Volume, Tidal Volume
Conditions
Keywords
Fluid Therapy, Hemodynamic Monitoring
Brief summary
This study evaluates predictability of fluid responsiveness of pressure-based dynamic variables such as pulse pressure variation and systolic pressure variation, according to tidal volume change in patients undergoing cardiac surgery.
Detailed description
Pressure-based dynamic variables such as pulse pressure variation(PPV) and systolic pressure variation(SPV) are known to be unreliable for prediction of fluid responsiveness in children. The hypothesis is that tidal volume change in mechanically ventilated children undergoing anesthesia would affect reliability of aforementioned dynamic variables in prediction of fluid responsiveness, especially in the way that reliability increases for high tidal volume. In children undergoing cardiac surgery, tidal volume is changed to 6mL/kg, 10mL/kg and 14mL/kg after closure of sternum, followed by measurement of PPV, SPV. We also measure the respiratory variation of aortic blood peak velocity(△Vpeak) via transesophageal echocardiography, which is known to best predict fluid responsiveness. Afterward, 10mL/kg of crystalloid solution is administered for fluid loading. 'Fluid responder' is defined as subjects with increase of stroke volume index more than 15% after fluid loading of 10mL/kg. With these data, whether the predictability of fluid responsiveness of PPV and SPV changes according to change in tidal volume is evaluated by comparing the area under the curve of the receiver-operating characteristics curve between themselves and △Vpeak.
Interventions
PROCEDURETidal volume_6mL/kg
Set tidal volume to 6mL/kg for 1 minute
PROCEDURETidal volume_10mL/kg
Set tidal volume to 10mL/kg for 1 minute
PROCEDURETidal volume_14mL/kg
Set tidal volume to 10mL/kg for 1 minute
PROCEDUREFluid loading
Administer 10mL/kg of crystalloid for 5 minutes
Sponsors
Seoul National University Hospital
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
SCREENING
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
No minimum to 5 Years
Healthy volunteers
No
Inclusion criteria
* Children younger than 6 years old planned to undergo ventricular septal defect closure or atrial septal defect closure under general anesthesia
Exclusion criteria
* Children with other complex cardiac defects * Children with arrhythmia * Children with preoperatively measured ejection fraction of less than 30% * Children with underlying pulmonary disease
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Stroke volume index | From sternal closure to 5 minutes after fluid loading | Define subject that shows increase of stroke volume index more than 15% after 10mL/kg of fluid loading as fluid responder, otherwise as non-responder |
| Predictability_PPV and SPV | From sternal closure to 5 minutes after fluid loading | Area under the curve of the receiver-operative characteristic curve for prediction of fluid responder of pulse pressure variation and systolic pressure variation after each change of set tidal volume |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Predictability_△Vpeak | From sternal closure to 5 minutes after fluid loading | Area under the curve of the receiver-operative characteristic curve for prediction of fluid responder of respiratory variation of aortic blood flow peak velocity measured via transesophageal echocardiography at tidal volume of 10mL/kg |
| Grey zone | From sternal closure to 5 minutes after fluid loading | Compare the range that the prediction of fluid responsiveness is unreliable (grey zone) for each variable in each set tidal volume |
Other
| Measure | Time frame | Description |
|---|---|---|
| Pulse oximetry | From start of anesthesia to end of anesthesia | Pulse oximetry determined by photoplethysmography (%) |
| End-tidal carbon dioxide | From start of anesthesia to end of anesthesia | End-tidal carbon dioxide measured from ventilatory circuit (mmHg) |
| Heart rate | From start of anesthesia to end of anesthesia | Heart rate determined by electrocardiogram (beats/min) |
Countries
South Korea
Outcome results
None listed