Croup 1 consisted of 36 subjects with chronic lung disease and REM sleep-related NOD discovered during nocturnal polysomnography. The NOD was defined as follows: (1) a baseline awake and non-rapid eye-movement (NREM) ear oximeter saturation of ^90 percent; (2) a fall below this value for five minutes or more, usually coinciding with but not limited to REM sleep; and (3) a nadir Sa02 value reaching 85 percent or lower. The predominant disease in all but one subject in group 1 was COPD.
That subject had symptoms of bronchitis but predominant restrictive disease based upon pulmonary function tests along with roentgenographic evidence of a thick peel over one lung from an old pleural empyema. In addition to symptomatic airflow obstruction, 11 patients may have had an element of restriction based upon history, or chest roentgenogram. Causes of the superimposed restrictive disease included pulmonary tuberculosis with parenchymal scarring, occupation related or idiopathic pulmonary fibrosis, or segmental lung resections for various reasons. www.cfm-online-shop.com
Group 2 consisted of 13 patients with historic, roentgenographic, and pulmonary function evidence of COPD. This group resembled the subjects in group 1 for age and FEV, but showed no evidence of REM sleep-related NOD under similar sleep laboratory monitoring conditions.
After classification into one of the two groups, subjects underwent extensive cardiopulmonary evaluation. Pooled radionuclide cardiac scans using previously described techniques were obtained to quantitate left ventricular (LVEF) and right ventricular ejection fractions (RVEF). Red blood cell (RBC) mass (chromium labeled technique) was determined in all subjects. Single breath carbon monoxide diffusion (Deo) was measured using standard techniques and published normal values. Alveolar oxygen tension (PaOJ was calculated from the equation Pa02 = (BP—Ph2o)0.21 – PaCO/R where BP is barometric pressure, Ph2o is alveolar water vapor pressure, PaC02 is arterial carbon dioxide tension, and R is the respiratory quotient (assumed to be 0.80).
Category: Lung Disease
Tags: chronic lung disease, Pulmonary function, pulmonary vascular hemodynamics