Hemodynamic and Respiratory Tolerance of Intermittent Hemodialysis in Critically Ill Patients

University Hospital, Toulouse200 enrolled

Overview

Acute kidney injury (AKI) affects up to 30% of critically ill patients and is associated with increased rates of mortality. Up to 60% of patients with AKI will ultimately require renal replacement therapy (RRT). Intermittent hemodialysis (IHD) is one of the main methods of RRT worldwide. In IHD-bicar, dialysate is composed by electrolytes, including calcium, and bicarbonate. To avoid calcium carbonate precipitation, dialysate has to be supplemented with acids (citric acid, chloride acid or acetic acid). However, IHD-bicar may be associated with hemodynamic instability or respiratory intolerance, mainly related to the CO2 release in the circulation during IHD (HCO3- \<--\> CO2 + H2O). Some recent studies showed that acetate free biofiltration (AFB-K), a technique that does not require dialysate acidification, could be associated with better hemodynamic stability and to a lower amount of CO2 delivered to the patients. AFB-K may thus improve the hemodynamic and respiratory tolerance of intermittent RRT in critically ill patients.

In this prospective observational study, investigators aim to characterize the hemodynamic and respiratory tolerances of HDI-bicar and AFB-K in critically ill patients requiring RRT.

Study Type

OBSERVATIONAL

Enrollment

200

Conditions

Acute Kidney Injury

Interventions

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Patients ≥ 18 years old * Invasive monitoring of blood pressure * Non opposition to the research * Admission to the intensive care unit * Need of intermittent hemodialysis Exclusion Criteria: * Sodium bicarbonate infusion * Pregnancy or breastfeeding * Juridical protection

Outcomes

Primary Outcomes

Occurence of hemodynamic event

The occurrence of at least one of the following events will be considered a hemodynamic event : * Hypotension (decrease of systolic or mean blood pressures ≥ 15 and ≥ 10% respectively) * Tachycardia (increase of heart beating ≥ 20%) * Cardiac arrythmia (junctional tachycardia, atrial fibrillation, flutter, ventricular tachycardia or fibrillation) * Decrease of the cardiac output ≥ 15% (only in patients with invasive cardiac output monitoring) * Starting (or increase dosing) of norepinephrine ≥ 0.1 µg/kg/min

Time frame: From admission to discharge, up to 4 hours

Secondary Outcomes

Change in maximal PaCO2

Evaluation of PaCO2 by arterial blood gas test

Time frame: 1 hour after the beginning of dialysis , up to 4 hours

Maximum difference of tcPCO2 and etCO2

Evaluation of TcPCO2 and etCO2 by trans-cutaneous measurement

Time frame: From admission to discharge, up to 4 hours

Change in the "strong ion difference"

Evaluation of the "strong ion difference" by blood ionogram

Time frame: baseline, 4 hours

Change in plasma pH

Evaluation of plasma pH by blood ionogram

Time frame: 1 hour after the beginning of dialysis session, up to 4 hours