Anesthesia, Cardiac Surgery, Echocardiography, Hemodynamics, Phenylephrine, Renal Perfusion, Ultrasonography, Renal
Conditions
Brief summary
To investigate the influence of PEEP (Positive end-expiratory pressure), changes in preload (patient position) and changes in afterload (phenylephrine) on ultrasound measures of renal perfusion in patients after uncomplicated cardiac surgery. To investigate the effects of phenylephrine on both invasive measures of the systemic- and pulmonary circulation and, secondarily, to assess the induced changes in echocardiographic indices of left- and right ventricular systolic- and diastolic function.
Interventions
DRUGPhenylephrine
Three time points: before, during and 20-30 minutes after infusion of phenylephrine. Patients will receive an infusion of up to 1 mcg/kg/min phenylephrine intravenously to raise mean arterial pressure with 20 mmHg for 10 minutes. Infusion of phenylephrine will start at 0.1 mcg/kg/min with subsequent titration to effect.
OTHERCombination of PEEP and positioning
Six time points based on combinations of the following: Three different levels of PEEP (as set on the ventilator): 0, 6 and 12 mmHg. Two different positions: 1) torso elevated 30 degrees, legs horizontal and 2) torso horizontal, legs elevated 30 degrees.
Sponsors
Aarhus University Hospital
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE
Masking description
Ultrasound analysis is performed offline and details on participants and time of measurement are blinded for the person doing the analysis. The personnel responsible for obtaining data will not be blinded towards any of the interventions.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* All patients ≥ 18 years scheduled for open elective cardiac surgery at the Department of Cardiothoracic & Vascular Surgery, Aarhus University Hospital.
Exclusion criteria
* Insufficient ultrasonographic imaging of the kidneys * Known morphological kidney disease * Preoperative dialysis * Chronic atrial fibrillation * Planned mitral valve surgery
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Renal arterial resistive index (RI). | 75 minutes |
| The ratio SVR/PVR (systemic vascular resistance/pulmonary vascular resistance) | 75 minutes |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Portal vein pulsatility fraction. | 75 minutes | — |
| Cardiac output | 75 minutes | — |
| Arterial blood pressure, central venous pressure, pulmonary blood pressure, pulmonary capillary wedge pressure. | 75 minutes | — |
| Transoesophageal measurement of left and right ventricular function 1 | 75 minutes | Systolic measure (ejection fraction (EF)) |
| Renal venous impedance index. | 75 minutes | — |
| Transoesophageal measurement of left and right ventricular function 3 | 75 minutes | Systolic measure (strain) |
| Transoesophageal measurement of left and right ventricular function 4 | 75 minutes | Diastolic measures (E, A,) |
| Transoesophageal measurement of left and right ventricular function 5 | 75 minutes | Diastolic measures (e', a') |
| Transoesophageal measurement of left and right ventricular function 6 | 75 minutes | Diastolic measure (deceleration time) |
| Transoesophageal measurement of left and right ventricular function 2 | 75 minutes | Systolic measure (s') |
| Renal venous stasis index. | 75 minutes | — |
Countries
Denmark
Outcome results
None listed