Clinical trial NCT01540916: Respiratory Alterations of Acid-base Equilibrium: Acute and Chronic Renal Response
Official title: Respiratory Alterations of Acid-base Equilibrium: Acute and Chronic Renal Response
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Acute Respiratory Variations of Acid-base Equilibrium
Keywords: acid-base equilibrium
renal system
urinary electrolytes
Lead sponsor: Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico
Sponsor class: OTHER
First posted: 2012-02-29
Enrollment: 50
Sex: ALL
Minimum age (years): 16
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: Alterations of acid-base equilibrium are very common in critically ill patients. Thus, understanding their pathophysiology and the possible compensatory mechanisms acting in different organs may play an important role in better set the consequent clinical treatment. The lung and the kidney are the two principal actors of such regulations. Although the respiratory response to acid-base alterations is well understood, less information are available for what the renal system is concerned. Such lack of information is partially due to: 1) the historical consideration of the kidney as a "slow" organ, in response to variations in acid-base equilibrium; 2) the lack of a monitoring system to closely assess renal response.

Our group has recently developed a monitoring system aimed at analyzing, in a quasi-continuous and non-invasive manner (every 10 min) the urinary profile in terms of urinary pH and electrolyte concentrations (sodium, potassium, chloride, ammonium).

The investigators hypothesize that the renal system reacts to large as well as to minimal variations of the acid-base equilibrium (especially induced by a variation in the respiratory function) in a very fast way, modifying the urinary concentration (and therefore the urinary excretion) of ammonium and some electrolytes (especially chloride).

Detailed description: Primary aim:

To investigate the acute renal response to respiratory alterations of acid-base equilibrium in order to better understand the underlying physiological mechanisms and to evaluate the validity of a renal monitoring system to indirectly assess the effectiveness of the respiratory function.

Secondary aim:

To collect data on the chronic response of the renal system in patients affected by chronic obstructive pulmonary disease (COPD), as well as on the acute response to acute variation of the chronic respiratory acidosis characterizing patients affected by COPD exacerbation.

Study protol:

Mechanically ventilated patients will undergo controlled variation of the ventilatory setting (hyperventilation vs. hypoventilation) in order to induce a controlled reduction or increase in arterial partial pressure of carbon dioxide (and an increase or reduction of arterial pH), within normal range of pH (7.35 - 7.45) During the variations, urinary concentrations of electrolytes and pH will be monitored.

Eligibility criteria: Inclusion Criteria:

1. Presence of mechanical ventilation
2. Presence of arterial and central venous line
3. Presence of urinary catheter

Exclusion Criteria:

1. acute or chronic renal failure with anuria
2. presence of continuous renal replacement therapy
3. hemodynamic instability
4. less than 16 years of age

Primary outcomes:
measure: Variations in urinary electrolyte concentrations and pH
timeFrame: From 0 to 4 hours
Secondary outcomes:
Other outcomes:
Locations:
city: Milan
country: Italy
facility: Terapia Intensiva Postoperatoria; Rianimazione Generale - Fondazione IRCCS Ca' Granda - Ospedale Maggiore Policlinico
Study officials:
affiliation: Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico
name: Pietro Caironi, MD
role: PRINCIPAL_INVESTIGATOR
References: