Hypovolemic
Conditions
Brief summary
The purpose of this study is to evaluate predictability of carotid corrected flow time for fluid responsiveness in mechanically ventilated patients with low tidal volume in the intensive care unit.
Interventions
Corrected carotid artery flow time is measured using 6-13 MHz linear probe on a portable ultrasound machine. On the two-dimensional image, the optimal image of the long-axis view is obtained at the left common carotid artery. The sample volume is placed on the center of the lumen, 2 cm proximal to the bulb, and a pulsed wave Doppler examination was performed while the Doppler beams were adjusted to ensure \< 60° of angle for the best signal. Then, cardiac cycle time and carotid flow time is measured. Carotid flow time is measured between the upstroke of the flow tracing and the dicrotic notch, and it is corrected for pulse rate by dividing flow time by the square root of the cardiac cycle time to calculate corrected carotid artery flow time (flow time/√cycle time).
Sponsors
Yonsei University
Study design
Observational model
CASE_ONLY
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
19 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1. Adult patients with age more than 19 2. Undergoing postoperative mechanical ventilation with low tidal volume 3. Clinically diagnosed with hypovolemic status 4. If one of follow criteria is satisfied 1) Systolic blood pressure \<90mmHg 2) Mean arterial pressure(MBP)\<70mmHg or fall more than 20% from baseline 3) Heart rate \>100bpm 4) Urine output \<0.5mg/kg/hr more than 1 hour 5) Arterial lactate \>2mmol/L 6) Capillary refilling time \>3secs
Exclusion criteria
1. Body mass index \<40 or \>15 kg/m2 2. Medical history of carotid artery stenosis \>50% or diagnosed while examination 3. Cardiac arrhythmia other than normal sinus rhythm 4. Moderate or severe valvular heart disease, intracardiac shunt, heart failure, pulmonary hypertension 5. Moderate or severe chronic obstructive pulmonary disease 6. Increased intracranial pressure 7. Using vasopressor 8. Pregnancy
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Corrected carotid artery flow time during low tidal volume ventilation | Procedure (During low tidal volume ventilation before fluid resuscitation) | Area under the receiver operating curve of Corrected carotid artery flow time for fluid responsiveness in low tidal volume ventilator setting before fluid resuscitation |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pulse pressure variation during low tidal volume ventilation | Procedure (During low tidal volume ventilation before fluid resuscitation) | Area under the receiver operating curve of pulse pressure variation for fluid responsiveness in low tidal volume ventilator setting before fluid resuscitation |
Countries
South Korea
Outcome results
None listed