Effects of Increasing Mean Arterial Pressure on Renal Function in Patients With Shock and With Elevated Central Venous Pressure (MAPAKI)

Effects of Increasing Mean Arterial Pressure on Renal Function in Patients With Shock and With Elevated Central Venous Pressure

Effects of Increasing Mean Arterial Pressure on Renal Function in Patients With Shock and With Elevated Central Venous Pressure : a Pilot Study for the Individualization of Mean Arterial Pressure

The purpose of this study is to assess the effect of a higher mean arterial pressure on renal function for patients with shock and elevated central venous pressure.

Current recommandation for mean arterial pressure (MAP) target is 65 mmHg for septic shock, but optimal target to prevent acute renal failure (ARF) remains unknown. High central venous pressure (CVP) can lead to acute renal failure through venous congestion , and is associated with acute renal failure in intensive care unit. A decrease of renal perfusion pressure, defined by MAP - CVP, has been shown to be associated with risk of acute renal failure. The main objective of this trial is to evaluate if an optimisation of renal perfusion pressure, by a higher MAP when CVP is high (≥ 12 cmH2O), can improve renal function. In this interventional monocenter trial, each patient will be evaluated during 2 consecutive periods of 6 hours, with a temporary MAP target Target at 65-70mmHg during 6 hours Target at 80-85mmHg during 6 hours Patients will be randomized into two groups to define the order of targets. There will be a stratification on previous arterial hypertension. Renal function will be measured at the end of each period.

Target of mean arterial pressure (MAP) at 65-70 mmHg The therapeutic means used to obtain the MAP objectives within each group (increase in catecholamines and / or volume expansion) are left to the discretion of the clinician, in accordance with the recommendations.

Target of mean arterial pressure (MAP) at 80-85 mmHg The therapeutic means used to obtain the MAP objectives within each group (increase in catecholamines and / or volume expansion) are left to the discretion of the clinician, in accordance with the recommendations.

Increase of mean arterial pressure at 65-70 mmHg (with catecholamines or volemic expansion at the discretion of the clinician)

Increase of mean arterial pressure at 80-85mmHg (with catecholamines or volemic expansion at the discretion of the clinician).

Creatinine clearance is calculated with the formula UV/P as follow : U being the urinary creatinine concentration in μmol/l V the urinary volume expressed in ml per unit time P the plasmatic creatinine concentration in μmol/l

We will assess the changes of the renal resistive index with a low MAP target (65-70mmHg) and with a high MAP target (80-85mmHg). Renal resistive index is measured with the use of doppler sonography and is calculated as follow : (peak systolic velocity - end diastolic velocity / peak systolic velocity) Renal resistive index from 3 waveforms are averaged to arrive at mean RI values for each kidney.

We will report rate of pre-existing conditions : ischemic heart disease, chronic heart failure, chronic obstructive pulmonary disease, chronic kidney disease, chronic kidney disease requiring long-term dialysis, liver cirrhosis, diabetes, cancer or autoimmune disease, chronic arterial hypertension.

Number of day with supportive care in intensive care unit (cathecolamines, renal replacement therapy, mechanical ventilation, extracorporeal membrane oxygenation)

Quantification of the number of days with supportive care (catecholamine,renal replacement therapy, mechanical ventilation, extracorporeal membrane oxygenation)

We will report the tricuspid annular plane systolic excursion (mm) measured on echocardiographic to evaluate the right ventricular function.

We will report the right S' wave (cm/s) measured on echocardiographic to evaluate the right ventricular function.

The pulmonary compliance (in ml/mmHg) will be calculated using the formula : Pulmonary compliance = Tidal volume / (plateau pressure - end-expiratory pressure).

We will record continuous cardiac output monitoring on pulse contour analysis of the invasive arterial blood pressure curve if the patient is monitored with Pulse index Continuous Cardiac Output (PICCO).

Inclusion Criteria: Adult patients (≥ 18 years old ) Arterial hypotension requiring the etablishment of catecholamines Norepinephrine dose ⩾ 0.1µg/kg/min at the inclusion High central venous pressure ≥ 12mmHg Cardiac output monitoring (PICCO or Swan Ganz) Exclusion Criteria: Anuria Patient with an emergency indication of renal replacement therapy (severe hyperkalemia, severe metabolical acidosis with pH <7.15, acute pulmonary edema due to fluid overload resulting in severe hypoxemia, serum urea concentration > 40 mmol/l) Pregnant, lactating or parturient woman Patient deprived of liberty by judicial or administrative decision Patient with psychiatric compulsory care Patient subject to legal protection measures Patients with do-no-reanimate order or withdrawal of life sustaining support