Oxygen delivery and consumption in critically ill pregnant patients: association with ophthalmic artery diastolic velocity.
OBJECTIVE
We aimed to investigate the relation between orbital vessel flow velocity and oxygen delivery, oxygen consumption, cardiac index, and systemic vascular resistance index in critically ill pregnant patients.


METHODS
Eighteen pregnant or early postpartum patients requiring invasive monitoring were prospectively studied with Doppler ultrasonography. The blood flow velocity and resistance index from the central retinal and ophthalmic arteries were plotted against the oxygen delivery index, oxygen consumption index, cardiac index, and systemic vascular resistance index. Linear and polynomial regression analysis and receiver-operator characteristic curves were used to examine the data.


RESULTS
The ophthalmic artery resistance index correlated with oxygen consumption, oxygen delivery index, and cardiac index. Only the cardiac index was independently related to the the ophthalmic artery resistance index. The ophthalmic artery diastolic velocity correlated with oxygen consumption index, oxygen delivery index, and cardiac index. The ophthalmic artery diastolic velocity correlated independently with mixed venous oxygen content and arteriovenous oxygen content difference. The central retinal artery Doppler index did not correlate with any of the invasively measured parameters. An ophthalmic artery diastolic velocity of > 7.12 cm/sec identified 75% of patients with an oxygen consumption index of < 140 ml/min per square meter and 91% of patients with an oxygen delivery index of < 600 ml/min per square meter.


CONCLUSIONS
These data suggest that the ophthalmic artery flow velocity is correlated with systemic oxygen delivery and consumption. This relationship may have potential research applications in the noninvasive assessment of oxygen delivery index and oxygen consumption index in critically ill pregnant patients.
Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX.
M A
MA
Belfort
G R
GR
Saade
D000293:Adolescent; D000328:Adult; D001783:Blood Flow Velocity; D002302:Cardiac Output; D016638:Critical Illness; D003971:Diastole; D005260:Female; D006801:Humans; D009880:Ophthalmic Artery / Q000000981:diagnostic imaging / Q000503:physiopathology*; D010100:Oxygen / Q000097:blood*; D010101:Oxygen Consumption; D011225:Pre-Eclampsia / Q000378:metabolism / Q000503:physiopathology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000378:metabolism* / Q000503:physiopathology; D011704:Pyelonephritis / Q000378:metabolism / Q000503:physiopathology; D012128:Respiratory Distress Syndrome / Q000378:metabolism / Q000503:physiopathology; D012680:Sensitivity and Specificity; D014463:Ultrasonography; D014655:Vascular Resistance
D010100:Oxygen