Am. J. Respir. Crit. Care Med.,
Volume 161, Number 5, May 2000, 1567-1571
Thoracoabdominal Compression and Respiratory System
Compliance in HIV-infected Infants
ARNOLD C. G.
PLATZKER,
ANDREW A.
COLIN,
XIN C.
CHEN,
PETER
HIATT,
JANICE
HUNTER,
ANATASSIOS C.
KOUMBOURLIS,
MARK D.
SCHLUCHTER,
ANDREW
TING,
and
MARY ELLEN
WOHL, for the Pediatric Pulmonary and Cardiovascular Complications of Vertically Transmitted HIV
(P2C2 HIV) Study
The Divisions of Pediatric Pulmonology, Childrens Hospital Los Angeles, and UCLA Children's Hospital, Los Angeles, California; Pulmonary Division,
Children's Hospital, Boston, Massachusetts; Department of Biostatistics and Epidemiology, The Cleveland Clinic Foundation, Cleveland, Ohio;
Clinical Care Center, Texas Children's Hospital, Houston, Texas; the Pediatric Pulmonary and Critical Care Division, Columbia Presbyterian
Medical Center, and the Pediatric Pulmonary and Critical Care Division, Mount Sinai School of Medicine, New York, New York
The thoracoabdominal compression technique (TAC) is used to
measure expiratory flow in infants. We investigated whether TAC caused a change in total thoracic compliance (Crs), resistance (Rrs), and respiratory system time constant (Trs). We studied 41 infants (mean age, 12.4 mo; SD, 7.5) from five centers studying longitudinal lung and cardiovascular function of infants from HIV-infected mothers. We measured Crs, Rrs, and Trs before and after
TAC. Changes in Crs, Rrs, and Trs after TAC were not dependent on the length of time since TAC. Crs and Trs were reduced after TAC, p = 0.013 and p = 0.003, respectively, whereas Rrs did not change. When compared with uninfected infants, HIV-infected infants had a larger post-pre TAC percent decline in Crs (p = 0.003)
and a post-pre TAC rise in mean Rrs (p = 0.03). These differences remained significant after adjusting for sex and age. When performing infant pulmonary function testing, TAC itself produces a
temporary decrease in Crs and Trs that is more significant in infants at risk for abnormal lung volume or compliance. Therefore,
the sequence of performing the infant lung function parameters
should be the same each time the testing is repeated with TAC as
the last parameter tested at each testing session.
