Indications for Cardiopulmonary Bypass During Pregnancy and Impact on
                    Fetal Outcomes

S.-M. Yuan

doi:10.1055/s-0033-1350997

Geburtshilfe und Frauenheilkunde, Inhaltsverzeichnis

Geburtshilfe Frauenheilkd 2014; 74(1): 55-62
DOI: 10.1055/s-0033-1350997

Review

GebFra Science

Georg Thieme Verlag KG Stuttgart · New York

Indications for Cardiopulmonary Bypass During Pregnancy and Impact on Fetal Outcomes

Indikationen für kardiopulmonalen Bypass in der Schwangerschaft und Auswirkung auf fetale Sterblichkeit

Authors

S.-M. Yuan

Department of Cardiothoracic Surgery, The First Hospital of Putian, Teaching Hospital, Fujian Medical University, Putian, Fujian Province, China

Abstract

Background: Cardiac operations in pregnant patients are a challenge for physicians in multidisciplinary teams due to the complexity of the condition which affects both mother and baby. Management strategies vary on a case-by-case basis. Feto-neonatal and maternal outcomes after cardiopulmonary bypass (CPB) in pregnancy, especially long-term follow-up results, have not been sufficiently described. Methods: This review was based on a complete literature retrieval of articles published between 1991 and April 30, 2013. Results: Indications for CPB during pregnancy were cardiac surgery in 150 (96.8 %) patients, most of which consisted of valve replacements for mitral and/or aortic valve disorders, resuscitation due to amniotic fluid embolism, autotransfusion, and circulatory support during cesarean section to improve patient survival in 5 (3.2 %) patients. During CPB, fetuses showed either a brief heart rate drop with natural recovery after surgery or, in most cases, fetal heart rate remained normal throughout the whole course of CPB. Overall feto-neonatal mortality was 18.6 %. In comparison with pregnant patients whose baby survived, feto-neonatal death occurred after a significantly shorter gestational period at the time of onset of cardiac symptoms, cardiac surgery/resuscitation under CPB in the whole patient setting, or cardiac surgery/resuscitation with CPB prior to delivery. Conclusions: The most common surgical indications for CPB during pregnancy were cardiac surgery, followed by resuscitation for cardiopulmonary collapse. CPB was used most frequently in maternal cardiac surgery/resuscitation in the second trimester. Improved CPB conditions including high flow, high pressure and normothermia or mild hypothermia during pregnancy have benefited maternal and feto-neonatal outcomes. A shorter gestational period and the use of CPB during pregnancy were closely associated with feto-neonatal mortality. It is therefore important to attempt delivery ahead of surgery/CPB or to defer surgery till late pregnancy.

Zusammenfassung

Einleitung: Herzoperationen an schwangeren Patientinnen stellen wegen der damit verbunden Komplexität, die Mutter und Kind gleichermaßen betreffen, eine Herausforderung für Chirurgen in interdisziplinären Teams dar. Die Behandlungsentscheidung hängt von der Einzelfallbewertung ab. Bislang wurden Müttersterblichkeit sowie das Überleben von Feten/Neugeborenen nach kardiopulmonalem Bypass („cardiopulmonary bypass“ CPB) der Mutter nicht ausreichend in der Literatur beschrieben, es fehlen insbesondere Ergebnisse der Langzeit-Verlaufsbeobachtung. Methodik: Dieser Übersichtsartikel basiert auf einer umfassenden Literaturrecherche für den Zeitraum von 1991 bis zum 30. April 2013. Ergebnisse: Die Indikation für den Einsatz von CPB während der Schwangerschaft stellten Herzoperationen in 150 (96,8 %) Patientinnen dar. Die häufigsten Eingriffe waren Herzklappenersatzoperationen wegen Aorten- und Mitralklappeninsuffizienz, Reanimation wegen Fruchtwasserembolie, Autotransfusion sowie Kreislaufunterstützung während des Kaiserschnitts in 5 Patientinnen. Während des CPB war entweder ein kurzer Abfall der fetalen Herzfrequenz zu verzeichnen, die sich nach der Operation wieder von selbst normalisierte, oder die fetale Herzfrequenz blieb während des ganzen CPB im Normalbereich. Die Gesamtsterblichkeit von Feten und Neugeborenen betrug 18,6 %. Verglichen mit Müttern, deren Feten/Kinder überlebten, war die fetale/neugeborenen Sterblichkeit signifikant höher, wenn mütterliche Herzinsuffizienzsymptome schon im früheren Gestationsalter auftraten bzw. bei kürzerer Schwangerschaftsdauer zum Operationszeitpunkt mit CPB. Schlussfolgerung: Die häufigsten chirurgischen Indikationen für CPB während der Schwangerschaft waren Herzoperationen, gefolgt von Reanimationen wegen kardiopulmonalem Kollaps. Die häufigsten Eingriffe mit CPB wurden während des 2. Trimesters vorgenommen. Bessere CPB-Bedingungen, darunter höhere Fließgeschwindigkeiten, höhere Blutdruckwerte und Normothermie, oder nur milde Hypothermie haben zu einer Verbesserung der mütterlichen und fetalen Ergebnisse geführt. Kurze Schwangerschaftsdauer zum Zeitpunkt des CPB war eng mit fetaler/neugeborener Sterblichkeit korreliert. Es wird empfohlen, die Entbindung vor dem Eingriff mit CPB vorzunehmen oder aber den Eingriff mit CPB auf einem möglichst späten Zeitpunkt zu verschieben.

Key words

birth - pregnancy - gynecology

Schlüsselwörter

Geburt - Schwangerschaft - Gynäkologie

Volltext

Referenzen

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