Respiratory CO2 response depends on plasma bicarbonate concentration in mechanically ventilated patients.
Med Intensiva
; 38(4): 203-10, 2014 May.
Article
em En
| MEDLINE
| ID: mdl-24411401
ABSTRACT
OBJECTIVE:
There is controversy about the effects of high plasma bicarbonate concentration ([HCO3(-)]) and the CO2 response test. We analyzed the relationship between [HCO3(-)] and the variation in hydrogen ion concentration (pH) for a given change in PaCO2, and its effects upon CO2 response.DESIGN:
A retrospective study was carried out.SETTING:
Two intensive care units. PATIENTS Subjects with and without chronic obstructive pulmonary disease (COPD), at the beginning of weaning from mechanical ventilation.INTERVENTIONS:
The CO2 response was evaluated by the re-inhalation of expired air method, measuring the hypercapnic ventilatory response (ΔVE/ΔPaCO2) and hypercapnic drive response (ΔP01/ΔPaCO2), where VE is minute volume and P0.1 is airway occlusion pressure 0.1s after the initiation of inspiration. MAIN OUTCOMEMEASURES:
[HCO3(-)] and CO2 response.RESULTS:
A total of 120 patients in the non-COPD group and 48 in the COPD group were studied. COPD patients had higher mean [HCO3(-)] than non-COPD patients (33.2 ± 5.4 vs. 25.7 ± 3.7 mmol/l, p<0.001). In both non-COPD and COPD patients we observed a significant inverse linear relationship between [HCO3(-)] and pH change per mmHg of PaCO2 (p<0.001), ΔVE/ΔPaCO2 (p<0.001) and ΔP0.1/ΔPaCO2 (p<0.001).CONCLUSIONS:
There is an inverse linear relationship between [HCO3(-)] and the variation of pH for a given change in PaCO2 and the CO2 response.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Respiração Artificial
/
Bicarbonatos
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Dióxido de Carbono
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Doença Pulmonar Obstrutiva Crônica
Tipo de estudo:
Observational_studies
Limite:
Aged
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Female
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Humans
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Male
/
Middle aged
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article