Cerebral oxygénation during prostaglandin E1 induced hypotension

Abstract

Purpose: To evaluate the cerebral oxygenation effects of hypotension induced by prostaglandin E t(PGEI) during fentanyl-oxygen anaesthesia. Methods: Ten patients who underwent elective cardiac surgery received infusion of PGE I . After measuring the baseline arterial, mixed venous and internal jugular vein blood gases, systemic haemodynamics, and regional cerebral oxygen saturation (rSO2) estimated by INVOS 3100 R, PGE, was continuously infused at 0.25-0.65 ~g'kg -*'min -t (mean dosage: 410 -+ 41.4 mg'kg -* -min -*) intravenously. Ten, 20 and 30 minutes after the start of drug infusions, blood gases described above were obtained simultaneously with the measurement of systemic haemodynamics and rSO 2. Thirty minutes from the start of drug infusions, administration of PGE, was stopped. The same parameters were measured again I 0, 30 minutes after the stop of drug infusion. Results: PGE, decreased mean arterial pressure (MAP) to approximately 70% of the baseline value (P < 0.05). PGE, increased mixed venous saturation, but in contrast did not effect internal jugular pressure, internal jugular oxygen saturation and rSO 2. Conclusions: These results suggest that PGE, is a suitable drug for induced hypotension because flow/metabolism coupling of brain and regional cerebral oxygenation were well maintained during hypotension.Objectif : l~valuer les effets de l'hypotension, induite par la prostaglandine E,(PGE~), sur l'oxygEnation c&Ebrale pendant l'anesthEsie avec fentanyl et oxygEne. M&hodes : Dix patients qui devaient subir une chirurgie cardiaque Elective ont re~u une perfusion de PGE i. Apt& avoir procEdE ~ la gazomEtrie art&ielle de base, ~ celle du sang veineux mEIE et ~ celle de la veine jugulaire interne, EvaluE rhEmodynamie systEmique et la saturation en oxygEne cErEbral regional (SO2r) par INVOS 3100R, la PGE, a EtE administrEe en perfusion intraveineuse continue ~ 0,25-0,65/~g'kg -l'min -l (dosage moyen : 410 +_ 41,4 ~g.min-i). Dix, 20 et 30 minutes apr& le debut des perfusions de medicaments, les gaz du sang dEj~ cites ont &6 obtenus simultanEment avec la mesure de l'hEmodynamie systEmique et laSOzr. Trente minutes aprEs le debut des perfusions, l'administration de la PGE I a EtE arr&Ee. Les m~mes paramEtres ont EtE mesurEs encore aprEs I0 et 30 minutes apr~s rarr& de la perfusion de medicament. R~sultats : La PGE i abaisse la tension art&ielle moyenne (TAM) ~. 70 % de sa valeur de base environ (P < 0,05). La PGE, augmente la saturation en oxygEne du sang veineux m~IE mais, au contraire, n'a pas d'effet sur la tension de la veine jugulaire interne, sur la saturation en oxygEne de cette veine et sur la SO2r. Conclusion : Ces rEsultats montrent que la PGE, est un medicament appropriE pour induire de l'hypotension parce que le couplage dEbit/mEtabolisme du cerveau et l'oxygEnation cEr~brale rEgionale ont EtE maintenus pendant l'hypotension.

Risks and benefits of deliberate hypotension in anaesthesia: a systematic review

“…The effect of induced hypotension on cerebral blood flow and oxygenation has been investigated using Doppler ultrasonography 47,49,50,85 , infrared spectroscopy 82 , thermal gradient blood flow meter 6 , measurement of difference in oxygen content in arterial and venous blood samples 60,72 , clearance of intra-arterially injected xenon 133 60 and electroencephalography 82,179,186 . Most studies showed no decrease in cerebral blood flow during hypotensive anaesthesia 4-6,8, 23,24,50,82,85,94,107,116,131,142,163,181,184,186,199 and even if there were a statistically significant reduction there was no evidence of a long-term adverse outcome clinically. One study entered in the final review showed no significant difference in cognitive test scores between patients receiving normotensive and hypotensive anaesthesia 153 .…”

Reduction of cerebral hyperemia with anti-hypertensive medication after electroconvulsive therapy

“…Drug doses were chosen based on the literature 6,12-13 and on previous clinical experience. [14][15] The identities of the study drugs were unknown to all persons present at the ECT session. The data obtained during this study were analyzed later by an individual who was also unaware of treatment regimens.…”

Cerebral oxygenation monitoring using near infrared spectroscopy during controlled hypotension

“…Nineteen patients (15 boys and four girls) ranging in age from 6 to 18 years (12.8 ± 3.5 years) and in weight from 25 to 70 kg (46.7 ± 13.8 kg) were enrolled in the study. The surgical procedures included anterior chest wall thoracoplasty (8), anterior spinal fusion (7), and femoral osteotomy (4). There were a total of 268 readings obtained from the cerebral oximeter.…”

“…Several studies have demonstrated the correlation of NIRS with cerebral tissue oxygenation or other measures of cerebral oxygenation such as jugular bulb venous oxygen saturation (4–8). Kim et al compared the correlation of NIRS and arterial oxygen saturation with jugular bulb venous oxygen saturation in 42 adult volunteers during hypoxemia (6).…”