[Study on the respiratory failure with cardiac failure--focus on hypoventilation respiratory failure]

Respiratory failure accompanied by cardiac failure occurs mostly due to decreased PaO2. However, sometimes we encounter patients with cardiac failure having on increase of PaCO2, who develop CO2 narcosis in the ICU. In this study we evaluated hypoventilation respiratory failure in patients with cardiac failure. Seventy-six patients with both respiratory failure and cardiac failure caused by intrinsic heart disease, who required mechanical ventilation in the ICU were studied. The patients were divided into 2 groups; hypoxic respiratory failure group (n = 53) and hypoventilation respiratory failure group (n = 23). Blood gas analysis and cardiovascular hemodynamics including arterial blood pressure, heart rate and Swan-Ganz catheter findings were performed before, during and after mechanical ventilation in each patient. Mortality rate and its relation to hemodynamic variables were also evaluated in each group. In both groups even when it was possible to maintain oxygenation capacity by conducting mechanical ventilation against severe respiratory failure, what can be said about the prognosis is that it depended totally on the improvement of cardiac function. The mechanism by which hypoxemia is displayed due to cardiogenic pulmonary edema is already well known, but in regard to the mechanism of hypercapnia in cases with hypersensitivity of the airways it is thought that through induction of cardiogenic pulmonary edema bronchial spasms is induced, and this causes hypercapnia. However, it is also possible to consider cardiac asthma as the cause. Among respiratory failure cases due to cardiogenic pulmonary edema that occurs in association with heart failure, there is both hypoxic respiratory failure as well as hypoventilation respiratory failure.(ABSTRACT TRUNCATED AT 250 WORDS)