GapCO2 and Respiratory Rate in Patients Under Volume Mechanical Ventilation

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

Status

UNKNOWN

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT02867943

Acronym

gapCO2

Enrollment

Registered

2016-08-16

Start date

2015-10-31

Completion date

2016-12-31

Last updated

2016-08-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Shock

Keywords

sepsis, shock,Lactate,volume controlled ventilation

Brief summary

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.

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.

Interventions

OTHEREffects 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

Study design

Observational model

COHORT

Time perspective

PROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

18 Years to 90 Years

Healthy volunteers

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.

Design outcomes

Primary

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

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026