Volume 3 Supplement 1
Assessment of intrathoracic blood volume and extravascular lung water by single transpulmonary thermodilution
© Current Science Ltd 1999
Published: 16 March 2000
The transpulmonary double-indicator dilution technique enables to measure the intrathoracic blood volume (ITBV) and extravascular lung water (EVLW). Since this technique is relatively time consuming and expensive, we studied whether the global end-diastolic volume (GEDV) which can be derived only from single indicator dilution (thermodilution) allows the estimation of intrathoracic blood volume.
In a heterogeneous population of 57 critically ill patients (56 ± 15 years) we found by structural regression analysis a correlation of ITBV = (1.25 × GEDV)–28.4 [ml]. We then applied this equation on the first double-indicator measurements in 209 other patients (52 ± 19 years) with sepsis (n = 98), ARDS (n = 31), head injury (n = 38, hemorrhagic shock (n = 19), intracranial hemorrhage (n = 19), brain infarction (n = 3), and heart failure (n = 1). Each patient received a 4 F flexible aortic catheter with an integrated thermistor and fiberoptic. Bolus injections used cooled (0–4°C) indocyanine green dissolved in glucose 5% in a concentration of 2 mg/ml.
At least for patients on a surgical intensive care unit, single transpulmonary thermodilution is sufficiently accurate for the estimation of intrathoracic blood volume and extravascular lung water.