Clinical application of transepithelial potential difference measurements in cystic fibrosis.

We studied transepithelial potential difference (PD) in normal persons, patients with chronic disease, and patients with cystic fibrosis (CF), using the technique described by Knowles and co-workers. A maximal PD value (PDmax) and an average PD value (PDmean) were determined for each study of the nasal respiratory epithelium. The voltage response to superfusion of 10(-4) mol/L amiloride onto nasal mucosa was noted. The PD of the palm, wrist, and between two fingertips was also measured. Nasal PDmax and PDmean of the CF group were more negative than the control (P less than 0.01) and chronic disease groups (P less than 0.01). After application of amiloride, the voltage change in nasal PD was greater in the CF group than in the non-CF control groups (P less than 0.01). There were no clinically significant differences in the PD of the palm, wrist, or fingertips of the three groups. These data confirm the observation that patients with CF have hyperpolarized nasal epithelia that demonstrate greater change in response to amiloride than that in non-CF controls. These results indicate a possible role for the use of in vivo nasal PD measurements as a diagnostic test for cystic fibrosis.

Total lung lavage for pulmonary alveolar proteinosis in an infant without the use of cardiopulmonary bypass.

Pulmonary alveolar proteinosis is a rare disease that usually affects the adult patient, but is now being recognized as a possible cause of neonatal respiratory distress. In the adult patient, whole lung lavage, as described by Ramirez-R in 1965, is considered the most effective therapy for management of this condition. The lavage can be accomplished safely and with relative ease by using a Carlens or Robertshaw tube to isolate and lavage one lung while ventilating the other. The unavailability of a small double-lumen tube makes this procedure impossible in the pediatric age group. Therefore, whole lung lavage has been possible in only a few children in the past with the help of cardiopulmonary bypass to allow simultaneous oxygenation during the pulmonary lavage. Due to the hazards and technical difficulties of cardiopulmonary bypass, total pulmonary lavage can not be considered a practical option in the very small infant. A 15-week-old infant is reported, weighing 2 kg with a diagnosis of pulmonary alveolar proteinosis, who underwent total pulmonary lavage safely on three different occasions without employing cardiopulmonary bypass. A double-lumen Swan-Ganz catheter, introduced transbronchoscopically through the side-arm of a rigid, 3.5-mm Storz bronchoscope was used to isolate and lavage one lung while ventilation to the other lung was maintained through the bronchoscope. A Nellcor oximeter, utilized for transcutaneous monitoring, revealed satisfactory oxygen saturation during the entire pulmonary lavage. The transbronchoscopic lavage was monitored under direct vision with a video monitor, ensuring correct position of the bronchoscope and the catheter at all times.(ABSTRACT TRUNCATED AT 250 WORDS)