Peripheral venous blood gases and pulse-oximetry in acute cardiogenic pulmonary oedema.
Eur Heart J Acute Cardiovasc Care
; 1(4): 275-80, 2012 Dec.
Article
em En
| MEDLINE
| ID: mdl-24062917
ABSTRACT
BACKGROUND:
The role of venous blood gases as an alternative to arterial blood gases in patients with severe acute heart failure has not been established.OBJECTIVE:
To assess the correlation between arterial and peripheral venous blood gases together with pulse-oximetry (SpO2), as well as to estimate arterial values from venous samples in the first hours upon admission of patients with acute cardiogenic pulmonary oedema.METHODS:
Simultaneous venous and arterial blood samples were extracted on admission and over the next 1, 2, 3, 4, and 10 hours. SpO2 was also registered at the same intervals.RESULTS:
A total of 178 pairs of samples were obtained from 34 consecutive patients with acute cardiogenic pulmonary oedema. Arterial and venous blood gases followed a parallel course in the first hours, showing high correlation rates at all time intervals. Venous samples underestimated pH (mean difference -0.028) and overestimated CO2 (+5.1 mmHg) and bicarbonate (+1 mEq/l). Conversely, SpO2 tended to underestimate SaO2 (mean±SD 93.1±9.1 vs. 94.2±8.4). Applying simple mathematical formulae based on these differences, arterial values were empirically calculated from venous samples, showing acceptable agreement in the Bland-Altman test. Likewise, a venous pH <7.32, pCO2 >51.3 mmHg, and bicarbonate <22.8 mEq/l could fairly identify arterial acidosis, either respiratory or metabolic, with a test accuracy of 92, 68, and 91%, respectively.CONCLUSIONS:
In patients with cardiogenic pulmonary oedema, arterial blood gas disturbances may be estimated from peripheral venous samples. By monitoring SpO2 simultaneously, arterial punctures could often be avoided.
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Base de dados:
MEDLINE
Idioma:
En
Ano de publicação:
2012
Tipo de documento:
Article