[Invasive and non-invasive diagnosis of pulmonary hypertension in the intensive care unit].

The diagnosis of chronic primary and secondary pulmonary hypertension is difficult. Important indications result from physical examination and the patient's history. Non-invasive diagnostic tools are chest X-ray, ECG, blood gas analysis and 2-D-Doppler-echocardiography. If, despite these investigations, no reason for the pulmonary hypertension is found, perfusion scintigraphy of the lungs and a right-heart catheter investigation should be performed. If there is no intracardiac shunting and perfusion scintigraphy of the lungs is normal, repeated pulmonary embolism must be excluded by pulmonary angiography. Only after elimination of this possibility can primary pulmonary hypertension be regarded as the reason for the patient's condition. Pulmonary hypertension is usually more acute in the critically ill patient. Under these circumstances, only direct pressure measurements are of clinical relevance. In the critical care setting, many of the non-invasive methods are either difficult to perform or hard to interpret. Furthermore, many of the typical signs of pulmonary hypertension derived from non-invasive investigations do not appear in acute pulmonary hypertension.