Neonatal Shock in the First Postnatal Day

Abstract

\s=b\ Advances in neonatal medicine have markedly reduced mortality in preterm infants. Current emphasis should be placed on early detection and treatment of neonatal hypotension and shock. Ideal clinical management includes perinatal recognition of low birth weight infants at risk for hypotension. All critically ill preterm infants should be closely monitored for tachycardia, hypotension, and/ or decreased urinary output. By use of noninvasive blood pressure screening techniques, hypotensive infants may be identified in the first hours of life. Judicious use of whole blood or balanced salt solutions will result in reduction of mortality from 50% to 10%.(Am J Dis Child 132: [509][510][511][512][513][514] 1978) A dvances in perinatal care have led *l\. to marked reductions in both maternal and neonatal mortality. Dis¬ cussions of the factors resulting in the increased survival of the small pre¬ term infant have centered around the importance of temperature and venti¬ latory support. Although this empha¬ sis has been appropriate up to now, it is becoming increasingly apparent that the vascular compartment and its support deserve the same critical attention. The purpose of this article is to present a review of infants exhib¬ iting shock in the first postnatal day, and to emphasize some of the factors vital to proper medical management. PRESSURE MONITORING Since the first determination of neonatal blood pressure by Ribemont1 in 1879, physicians have sought reli¬ able devices for measuring blood pres¬ sure in the neonate. Some investiga¬ tors have expressed confidence in indirect monitoring methods; others, however, have stated that such meth¬ ods are unreliable because of the reduced peripheral blood flow in sick From the NE 68105 (Dr Paxson). infants.2 Those who prefer to avoid indirect methods suggest the use of direct blood pressure monitoring via vessel catheterization. Although di¬ rect methods are useful in certain infants, the complications of catheter¬ ization prevent its routine use for evaluating all infants at risk for hypo¬ tension.3-4Recent reports have claimed preci¬ sion for two noninvasive blood pres¬ sure devices that may be used for testing all infants for impending hypotension: the xylol pulse indica¬ tor5·6 and the Doppler ultrasound device.7" The xylol pulse indicator is a reliable blood pressure device for obtaining systolic pressures in the neonate. Unfortunately, the device is not readily available in this country for routine clinical use. Much experi¬ ence has been reported with the Doppler device, and the values re¬ ported correlate well with those obtained by the direct technique in both normotensive and hypotensive patients.8"' Criticism specifically di¬ rected against the Doppler technique has been that it is time-consuming and awkward.7 This criticism has not been confirmed by additional experi¬ ence, however, and the technique is considerably more reliable than the methods of flush, palpation, or ausculation.8-11

Neonatal effects of maternal administration of acebutolol.

“…A mean of three successive readings that did not differ by more than 5 mm Hg was noted. The "expected" systolic blood pressure (SBP) was calculated using the formula of Bucci et all' as adapted by Paxson,12 which uses the principal determinative factors of birth weight (BW; in kg), gestational age (GA; in weeks), and postnatal age (PA; in days): SBP=23-2+8 13 BW+0 503 GA+0 226 PA-0 0016 PA2. The measured systolic blood pressure was expressed as the percentage of that expected.…”

Usefulness of a New Doppler Index for Assessing Both Ventricular Functions and Pulmonary Circulation in Newborn Piglet With Hypoxic Pulmonary Hypertension

“…Historically, these infants may have had severe perinatal asphyxia (26,27) or an obstetric complication (e.g. abruptio placentae or placenta previa) that caused significant fetal hemorrhage (28). A significant number of stressed infants experience myocardial infarcts in the context of perinatal asphyxia (27,29).…”