Effects of awake caudal anesthesia on mean arterial blood pressure in very low birthweight infants

Object. It is taken for granted that patients with hypertension are at greater risk for intracerebral hemorrhage during neurosurgical procedures than patients with normal blood pressure. The anesthesiologist, therefore, maintains mean arterial blood pressure (MABP) near the lower end of the autoregulation curve, which in patients with preexisting hypertension can be as high as 110 to 130 mm Hg. Whether patients with long-standing hypertension experience more hemorrhage than normotensive patients after brain surgery if their blood pressure is maintained at the presurgical hypertensive level is currently unknown. The authors tested this hypothesis experimentally in a rodent model.Methods. Hemorrhage and edema in the brain after needle biopsy was measured in vivo by using three-dimensional magnetic resonance (MR) microscopy in the following groups: WKY rats, acutely hypertensive WKY rats, spontaneously hypertensive rats (SHR strain), and SHR rats treated with either sodium nitroprusside or nicardipine. Group differences were compared using Tukey's studentized range test followed by individual pairwise comparisons of groups and adjusted for multiple comparisons.There were no differences in PaCO2, pH, and body temperature among the groups. The findings in this study indicated that only acutely hypertensive WKY rats had larger volumes of hemorrhage. Chronically hypertensive SHR rats with MABPs of 130 mm Hg did not have larger hemorrhages than normotensive rats. There were no differences in edema volumes among groups.Conclusions. The brains of SHR rats with elevated systemic MABPs are probably protected against excessive hemorrhage during surgery because of greater resistance in the larger cerebral arteries and, thus, reduced cerebral intravascular pressures.

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Cerebroelectrical Depression Following Surfactant Treatment in Preterm Neonates

PEDIATRICS ◽

10.1542/peds.89.4.643 ◽

1992 ◽

Vol 89 (4) ◽

pp. 643-647 ◽

Cited By ~ 4

Author(s):

Lena Hellström-Westas ◽

Nils W. Svenningsen ◽

Angela H. Bell ◽

Liselotte Skov ◽

Gorm Greisen

Keyword(s):

Blood Pressure ◽

Arterial Blood Pressure ◽

Mean Arterial Blood Pressure ◽

Intraventricular Hemorrhage ◽

Preterm Neonates ◽

Cerebral Function ◽

Surfactant Treatment ◽

Arterial Blood ◽

Cerebral Dysfunction ◽

Almost All

During surfactant treatment of respiratory distress syndrome, 23 premature newborns were investigated with continuous amplitude-integrated electroencephalography (cerebral function monitors). Simultaneously, arterial blood pressure and transcutaneous blood gas values were recorded. A short(<10 minutes) but significant decrease in cerebral activity was seen in almost all neonates immediately after the surfactant instillation, in spite of an improved pulmonary function. In 21 of 23 neonates, a transient fall in mean arterial blood pressure of 9.3 mm Hg (mean) occurred coincidently with the cerebral reaction. Neonates in whom intraventricular hemorrhage developed tended to have lower presurfactant mean arterial blood pressure (P> .05), but they had a significantly lower mean arterial blood pressure after surfactant instillation (P < .05). No other differences were found between neonates in whom intraventricular hemorrhage developed and those without intraventricular hemorrhage. The present findings demonstrate that an acute cerebral dysfunction may occur after surfactant instillation. In some vulnerable neonates with arterial hypotension and severe pulmonary immaturity,the fall in mean arterial blood pressure may increase the risk of cerebral complications and could be related to an unchanged rate of intraventricular hemorrhage after surfactant treatment.

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Modeling Cerebral Blood Flow Dependence on Carbon Dioxide and Mean Arterial Blood Pressure in the Immature Brain With Accounting for the Germinal Matrix

Frontiers in Neurology ◽

10.3389/fneur.2018.00812 ◽

2018 ◽

Vol 9 ◽

Cited By ~ 7

Author(s):

Irina Sidorenko ◽

Varvara Turova ◽

Nikolai Botkin ◽

Laura Eckardt ◽

Ana Alves-Pinto ◽

...

Keyword(s):

Carbon Dioxide ◽

Blood Pressure ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Arterial Blood Pressure ◽

Mean Arterial Blood Pressure ◽

Immature Brain ◽

Germinal Matrix ◽

Arterial Blood ◽

Flow Dependence

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Effect of the Ace Inhibitor Ceronapril on Cerebral Blood flow in Hypertensive Patients

Annals of Pharmacotherapy ◽

10.1177/106002809603000601 ◽

1996 ◽

Vol 30 (6) ◽

pp. 578-582 ◽

Cited By ~ 5

Author(s):

Neal R Cutler ◽

John J Sramek ◽

Azucena Luna ◽

Ismael Mena ◽

Eric P Brass ◽

...

Keyword(s):

Blood Pressure ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Diastolic Blood Pressure ◽

Arterial Blood Pressure ◽

Mean Arterial Blood Pressure ◽

Enzyme Inhibitor ◽

Blood Pressure Response ◽

Combined Therapy ◽

Arterial Blood

Objective To assess the effect of the angiotensin-converting enzyme inhibitor ceronapril on cerebral blood flow (CBF) in patients with moderate hypertension. Design Patients received chlorthalidone 25 mg for 4 weeks, and if diastolic blood pressure remained in the range of 100–115 mm Hg, they were given titrated doses of ceronapril (10–40 mg/d based on blood pressure response) in addition to chlorthalidone for 9 weeks. Setting Outpatient research clinic. Subjects Eligible patients had moderate essential hypertension (diastolic blood pressure 100–115 mm Hg) assessed when the patients were receiving no medications. Thirteen patients were entered into the study; 1 withdrew for reasons unrelated to the study drug. Twelve patients (11 men, 1 woman; mean age 52 y) completed the study. Intervention Ceronapril, given with chlorthalidone. Main Outcome Measures CBF measurements were taken at the start and end of ceronapril therapy using intravenous 133Xe; blood pressures were determined weekly. Results Mean arterial blood pressure decreased from 130 ± 4 to 120 ±7 mm Hg after 4 weeks of chlorthalidone administration, and fell further to 108 ± 8 mm Hg after an additional 9 weeks of combined chlorthalidone-ceronapril therapy (p < 0.05). CBF fell from 44 ± 15 to 34 ± 5 mL/min/100 g during the 9 weeks of combined therapy (p = 0.05). No adverse effects consistent with decreased CBF were observed. The decrease in CBF was not linearly correlated with the change in systemic blood pressure, but was strongly correlated (r = –0.937; p < 0.001) with the initial CBF. Conclusions The decrease in mean arterial blood pressure was not associated with a decrease in CBF. Patients with high CBF may be predisposed to a decrease in CBF when treated with ceronapril and chlorthalidone.

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