The effect of exogenous surfactant therapy on lung function following cardiopulmonary bypass.

OBJECTIVE

Pilot study to investigate the effect of exogenous surfactant therapy on lung function following cardiopulmonary bypass (CPB).

DESIGN

Prospective randomized controlled study.

SETTING

Adult intensive care unit of a postgraduate cardiothoracic hospital.

PATIENTS

Sixteen adult patients undergoing elective coronary artery revascularization surgery without a history of preoperative respiratory disease.

INTERVENTIONS

Artificial lung-expanding compound (ALEC, Britannia Pharmaceuticals, Crawley, UK) 3.2 g, was given via a bronchoscope 60 min after bypass in eight patients. Eight control subjects received air.

MAIN OUTCOME MEASUREMENTS

Lung function tests during IPPV (arterial blood gas tensions, Crs, FRC, TLco, KCO) were measured prior to CPB, before therapy, and at regular intervals up to 180 min afterwards.

RESULTS

The CPB caused a significant impairment of lung function in both groups with an increase in A-a gradient (+47 +/- 11 mm Hg in the ALEC group and +44 +/- 17 mm Hg in controls) and reductions in FRC (-290 +/- 121 ml in the ALEC group and -470 +/- 132 ml in controls), TLco (-1.6 +/- 0.3 ml/min/mm Hg in the ALEC group and -2.2 +/- 0.3 ml/min/mm Hg in controls), and Crs (-10 +/- 1 ml/cm H2O in the ALEC group and -21 +/- 4 ml/cm H2O in controls). The ALEC therapy did not affect A-a gradient, FRC, and Crs compared with controls. However, TLco was significantly lower in the ALEC group following therapy (120 min after treatment -0.1 +/- 0.3 ml/min/mm Hg in ALEC group and +1.0 +/- 0.3 ml/min/mm Hg in controls).

CONCLUSIONS

A single 3.2-g dose of ALEC administered as a bolus bronchoscopically does not improve lung function following CPB and may impair gas transfer.