Respiratory Alterations of Acid-base Equilibrium: Acute and Chronic Renal Response

NCT ID: NCT01540916

Last Updated: 2015-11-10

Basic Information

• Recruitment Status: UNKNOWN
• Clinical Phase: NA
• Total Enrollment: 50 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2012-02-29
• Study Completion Date: 2015-11-30

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.

Conditions

Acute Respiratory Variations of Acid-base Equilibrium

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

Hyperventilation

Minute ventilation will be increased of about 30% of baseline value, through an increase in respiratory rate

Group Type: EXPERIMENTAL

Increase minute ventilation

Intervention Type: OTHER

Respiratory rate will be increase in order to have a 30% increase of minute ventilation

Hypoventilation

Minute ventilation will be decreased of about 30% of baseline value, through a decrease in respiratory rate

Group Type: EXPERIMENTAL

Decrease minute ventilation

Intervention Type: OTHER

Respiratory rate will be decrease in order to have a 30% decrease of minute ventilation

Interventions

Increase minute ventilation

Respiratory rate will be increase in order to have a 30% increase of minute ventilation

Intervention Type: OTHER

Decrease minute ventilation

Respiratory rate will be decrease in order to have a 30% decrease of minute ventilation

Intervention Type: OTHER

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

• Minimum Eligible Age: 16 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Pietro Caironi, MD

Role: PRINCIPAL_INVESTIGATOR

Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico

Locations

Terapia Intensiva Postoperatoria; Rianimazione Generale - Fondazione IRCCS Ca' Granda - Ospedale Maggiore Policlinico

Milan, , Italy

Countries

Italy

Other Identifiers

842

Identifier Type: -

Identifier Source: org_study_id