title: Randomised double-blinded comparison of phenylephrine vs ephedrine for maintaining blood pressure during spinal anaesthesia for non-elective Caesarean section*.
abstract: In a randomised, double-blinded study, we compared boluses of phenylephrine 100 microg with ephedrine 10 mg for treating hypotension (systolic blood pressure < 100 mmHg) in 204 patients having non-elective Caesarean section under spinal anaesthesia. Umbilical arterial (UA) and venous (UV) pH and base excess were similar between groups. In the ephedrine group, UA lactate concentration was higher (median 2.6 [interquartile range 2.3-3.3] vs 2.4 [1.9-3.0] mmolxl(-1), p = 0.002) and UV lactate concentration was higher (2.5 [2.2-3.2] vs 2.3 [1.9-2.8] mmolxl(-1), p = 0.016) and more patients had nausea or vomiting (12.7% vs 3.9%, p = 0.02). Clinical neonatal outcome was similar. Of the protocol-compliant patients (n = 148), UA Po(2) and UV Po(2) were lower in the phenylephrine group although oxygen content was similar. We conclude that phenylephrine and ephedrine are both suitable vasopressors for use in non-elective Caesarean sections.
authors.affiliation: Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong, China. warwick@cuhk.edu.hk
authors.forename: W D
authors.initials: WD
authors.lastname: Ngan Kee
authors.forename: K S
authors.initials: KS
authors.lastname: Khaw
authors.forename: T K
authors.initials: TK
authors.lastname: Lau
authors.forename: F F
authors.initials: FF
authors.lastname: Ng
authors.forename: K
authors.initials: K
authors.lastname: Chui
authors.forename: K L
authors.initials: KL
authors.lastname: Ng
mesh_terms: D000328:Adult; D000773:Anesthesia, Obstetrical / Q000009:adverse effects*; D000775:Anesthesia, Spinal / Q000009:adverse effects*; D001794:Blood Pressure / Q000187:drug effects; D002245:Carbon Dioxide / Q000097:blood; D002585:Cesarean Section; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D004809:Ephedrine / Q000008:administration & dosage / Q000627:therapeutic use*; D005260:Female; D005312:Fetal Blood / Q000378:metabolism; D006801:Humans; D007022:Hypotension / Q000209:etiology / Q000517:prevention & control*; D007431:Intraoperative Complications / Q000517:prevention & control; D019344:Lactic Acid / Q000097:blood; D010100:Oxygen / Q000097:blood; D010313:Partial Pressure; D010656:Phenylephrine / Q000008:administration & dosage / Q000627:therapeutic use*; D011247:Pregnancy; D014662:Vasoconstrictor Agents / Q000008:administration & dosage / Q000627:therapeutic use*
chemical_list: D014662:Vasoconstrictor Agents; D002245:Carbon Dioxide; D010656:Phenylephrine; D019344:Lactic Acid; D004809:Ephedrine; D010100:Oxygen