Pulmonary artery pressure monitoring in the surgical intensive care unit. Benefits vs difficulties.

The process of pulmonary artery pressure monitoring in 50 consecutive patients in the surgical intensive care unit was analyzed to determine the number and types of problems that occurred in relation to the benefit obtained. Twenty-six percent of the patients had a change in their cardiorespiratory therapy and their conditions were improved after the pressure data were obtained. Many technical and interpretative problems that tended to decrease the desirability of using pulmonary artery pressure monitoring were identified. Most problems could be avoided by carefully calibrating the monitor system, clearing the catheter system of air bubbles and blood clots, learning to property interpret pulmonary artery pressure tracings despite large respiratory variations, and obtaining a hard-copy printout of the pressure tracing with the simultaneous ECG signal. A protocol for avoiding many difficulties was developed.