Hi. Chait et al., INFERIOR VENA-CAVAL PRESSURE RELIABLY PREDICTS RIGHT ATRIAL PRESSURE IN PEDIATRIC CARDIAC SURGICAL PATIENTS, Critical care medicine, 22(2), 1994, pp. 219-224
Objective: To compare ''central venous pressure'' in pediatric patient
s in a clinical setting as measured from catheters in the infrahepatic
inferior vena cava and the right atrium. Design: Prospective, unblind
ed study. Setting: Cardiothoracic intensive care unit of a tertiary ca
re university hospital. Patients: Thirty-three pediatric cardiac surgi
cal patients, 2 days to 92 months of age (mean 24 +/- 4 months). Inter
ventions: Ah patients had intraoperative placement of an 8-cm, double-
lumen, femoral venous catheter and a transthoracic right atrial cathet
er. Patients were studied for 0 to 2 days after surgery. Measurements
and Main Results: Measurements were obtained during mechanical and spo
ntaneous ventilation. Although not statistically identical, measuremen
ts of ''central'' venous pressure in the inferior vena cava and right
atrium correlated well (r(2) = .87 for mechanical ventilation; r(2) =
.83 for spontaneous ventilation). Of 31 data pairs in mechanically ven
tilated patients, the absolute difference in pressures was as large as
3 mm Hg in three patients and <3 mm Hg in all the rest. In 15 spontan
eously breathing patients, there were only three data measurements whe
re the difference in pressure was 2 mm Hg and none of the differences
was greater. In spontaneously breathing patients, the phasic changes d
ue to respiratory variations in venous pressure were in phase in both
the intrathoracic and intra-abdominal catheter positions. Conclusions:
We conclude that while ''central'' venous pressures measured in the i
nferior vena cava and in the right atrium are not statistically identi
cal, any differences are well within clinically important limits, Plac
ement of central venous pressure catheters in the inferior vena cava b
y the femoral venous approach is a reliable alternative to cannulating
the superior vena cava in pediatric patients without clinically impor
tant intra-abdominal pathology and with anatomic continuity of the inf
erior vena cava with the right atrium. Relatively short femoral vein c
atheters allow adequate measurement of central venous pressure without
concern for exact catheter tip position and without the risk of right
atrial perforation, intracardiac arrhythmias, and inadvertent punctur
e of carotid and intrathoracic structures. Unlike previously reported
results in neonates, we found that the phasic changes of venous pressu
re with the respiratory cycle were similar in both intrathoracic and i
ntra-abdominal recordings, making this an inappropriate clinical indic
ator of venous catheter tip position.