Anesthetic techniques for fetal surgery: effects of maternal anesthesia on intraoperative fetal outcomes in a sheep model.
BACKGROUND
Use of high-dose inhalational anesthesia during open fetal surgery may induce maternal-fetal hemodynamic instability and fetal myocardial depression. The authors' preliminary human retrospective study demonstrated less fetal bradycardia and left ventricular systolic dysfunction with lower dose desflurane supplemented with propofol and remifentanil IV anesthesia (SIVA). In this animal study, the authors compare maternal-fetal effects of high-dose desflurane anesthesia (HD-DES) and SIVA.


METHODS
Of 26 instrumented midgestational ewes, data from 11 animals exposed to both SIVA and HD-DES in random sequences and six animals exposed to HD-DES while maternal normotension was maintained were analyzed. Maternal electroencephalography was used to guide comparable depths of anesthesia in both techniques. Hemodynamic parameters, blood gas, and fetal cardiac function from echocardiography were recorded.


RESULTS
Compared with SIVA, HD-DES resulted in significant maternal hypotension (mean arterial pressure difference, 19.53 mmHg; 95% CI, 17.6-21.4; P < 0.0001), fetal acidosis (pH 7.11 vs. 7.24 at 150 min, P < 0.001), and decreased uterine blood flow. In the HD-DES group with maternal normotension, uterine blood flow still declined and fetal acidosis persisted, with no statistically significant difference from the group exposed to HD-DES that had maternal hypotension. There was no statistically significant difference in fetal cardiac function.


CONCLUSIONS
In sheep, SIVA affects maternal hemodynamics less and provides better fetal acid/base status than high-dose desflurane. Fetal echocardiography did not reflect myocardial dysfunction in this model.
Department of Anesthesiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA. pornswan.ngamprasertwong@cchmc.org
Pornswan
P
Ngamprasertwong
Erik C
EC
Michelfelder
Shahriar
S
Arbabi
Yun Suk
YS
Choi
Christopher
C
Statile
Lili
L
Ding
Anne
A
Boat
Pirooz
P
Eghtesady
Katherine
K
Holland
Senthilkumar
S
Sadhasivam
D000136:Acid-Base Equilibrium / Q000187:drug effects; D000138:Acidosis / Q000139:chemically induced; D000773:Anesthesia, Obstetrical / Q000379:methods*; D019162:Anesthetics, Combined / Q000494:pharmacology; D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D018686:Anesthetics, Intravenous / Q000494:pharmacology*; D000818:Animals; D062186:Arterial Pressure / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D018592:Cross-Over Studies; D000077335:Desflurane; D004569:Electroencephalography / Q000379:methods; D005260:Female; D005333:Fetus; D006340:Heart Rate, Fetal / Q000187:drug effects*; D007431:Intraoperative Complications / Q000139:chemically induced*; D007530:Isoflurane / Q000031:analogs & derivatives / Q000494:pharmacology; D016343:Monitoring, Intraoperative / Q000379:methods; D010880:Piperidines / Q000494:pharmacology; D011247:Pregnancy; D015742:Propofol / Q000494:pharmacology; D012039:Regional Blood Flow / Q000187:drug effects; D000077208:Remifentanil; D012756:Sheep; D014599:Uterus / Q000098:blood supply / Q000187:drug effects*
D019162:Anesthetics, Combined; D018685:Anesthetics, Inhalation; D018686:Anesthetics, Intravenous; D010880:Piperidines; D000077335:Desflurane; D007530:Isoflurane; D000077208:Remifentanil; D015742:Propofol