GapCO2 and Respiratory Rate in Patients Under Volume Mechanical Ventilation (gapCO2)

August 16, 2016 updated by: 105 Hospital of Chinese People's Liberation Army

Effects of Respiratory Rate on Venous-to-arterial CO2 Tension Difference in Septic Shock Patients Under Volume Mechanical Ventilation

As an approximate of the difference between venous-to-arterial CO2 tension (∆PCO2), ∆PCO2 is proportional to CO2 production and inversely related to cardiac output (Fick equation). Anaerobic CO2 production is thought to occur when tissue hypoxia is present, mostly because of buffering of bicarbonate ions by the protons produced in excess secondary to the hydrolysis of adenosine triphosphate. Therefore ∆PCO2 has been proposed as a marker of tissue hypoxia.

Study Overview

Status

Unknown

Conditions

Intervention / Treatment

Detailed Description

An increased ∆PCO2 (> 6 mmHg) could be used to identify patients who still remain inadequately resuscitated, when deciding when to continue resuscitation despite a central venous oxygen saturation (ScvO2) > 70% associated with elevated blood lactate levels.

Under steady states of both VO2 and VCO2, P (v-a) CO2 was observed to increase in parallel with the reduction in cardiac output. However, spontaneous breathing and hyperventilation may reduce PaCO2 and prevent the CO2 stagnation-induced rise in PvCO2.

To date,these studies of ∆PCO2 and respiratory rate in septic shock patients Under Volume Mechanical Ventilation are rarely.

Study Type

Observational

Enrollment (Anticipated)

28

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 90 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

The subjects were sequentially admitted to the Department of Critical Care Medicine of 105 Hospital of PLA from March of 2016 till the end of this study.

Description

Inclusion Criteria:

Patients were included in the study, if the attending physician find the persistence of signs of hypoperfusion (oliguria, mottled skin, central venous oxygen saturation (ScvO2) <70 % despite a hemoglobin > 8 g/dl),despite achieving adequate intravascular volume and adequate mean arterial pressure (MAP) > 65 mmHg as recommended by the Surviving Sepsis Campaign.

Exclusion Criteria:

Exclusion criteria were pregnancy, COPD，age less than 18 years old, unstable hemodynamic condition (change of vasoactive drug dosage or fluid administration within 1 h preceding the protocol) and uncontrolled tachyarrhythmias (heart rate>140 beats/min).

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Observational Models: Cohort
  • Time Perspectives: Prospective

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
respiratory rate is 10 breaths/min

GapCO2=Pv-aCO2 = PvCO2 - PaCO2;

Effects of venous-to-arterial CO2 tension difference after increased respiratory rate.
Other: Effects of respiratory rate on gapCO2
respiratory rate was started at 10 breaths/min and added by 2 breaths/min every 60 min up to 16 breaths/min
respiratory rate is 12 breaths/min

GapCO2=Pv-aCO2 = PvCO2 - PaCO2;

Effects of venous-to-arterial CO2 tension difference after increased respiratory rate.
Other: Effects of respiratory rate on gapCO2
respiratory rate was started at 10 breaths/min and added by 2 breaths/min every 60 min up to 16 breaths/min
respiratory rate is 14 breaths/min

GapCO2=Pv-aCO2 = PvCO2 - PaCO2;

Effects of venous-to-arterial CO2 tension difference after increased respiratory rate.
Other: Effects of respiratory rate on gapCO2
respiratory rate was started at 10 breaths/min and added by 2 breaths/min every 60 min up to 16 breaths/min
respiratory rate is 16 breaths/min

GapCO2=Pv-aCO2 = PvCO2 - PaCO2;

Effects of venous-to-arterial CO2 tension difference after increased respiratory rate.
Other: Effects of respiratory rate on gapCO2
respiratory rate was started at 10 breaths/min and added by 2 breaths/min every 60 min up to 16 breaths/min

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Effects of respiratory rate on venous-to-arterial CO2 tension difference in septic shock patients Under Volume Mechanical Ventilation
Time Frame: 1 year
1 year

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

105 Hospital of Chinese People's Liberation Army

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

October 1, 2015

Primary Completion (Anticipated)

October 1, 2016

Study Completion (Anticipated)

December 1, 2016

Study Registration Dates

First Submitted

August 11, 2016

First Submitted That Met QC Criteria

August 11, 2016

First Posted (Estimate)

August 16, 2016

Study Record Updates

Last Update Posted (Estimate)

August 18, 2016

Last Update Submitted That Met QC Criteria

August 16, 2016

Last Verified

August 1, 2016

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • PLA-105-ICU

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

Yes

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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