Ramin 1994.

Study characteristics
Methods	RCT
Participants	32 women Inclusion criteria: healthy pregnant women undergoing elective caesarean at term (38 to 40 weeks' gestation) with spinal anaesthesia Exclusion criteria: women in labour, hypertension, diabetes, platelet counts < 100,000 mm3, prolonged thromboplastin time, fetal distress, cardiac or pulmonary disease, any medical illness, or a known history of drug abuse
Interventions	Prophylactic angiotensin versus prophylactic ephedrine versus control Group 1: angiotensin II (1000 ng/mL in 0.9% sodium chloride) Group 2: ephedrine (1 mg/mL) Group 3: control (no prophylactic intervention) All women received a standardised crystalloid preload and a standardised spinal anaesthetic technique with slight variation in spinal anaesthetic doses.
Outcomes	Maternal: hypotension (defined as decrease of > 30% from baseline); arterial BP (mean and SD); angiotensin levels Neonatal: Apgar scores at 1 min and 5 min (mean and SD); pH < 7.2; umbilical artery pH (mean and SD); umbilical venous pH (mean and SD); pCO2; BE
Notes	Hypotension was defined as a decrease in BP of > 30% from baseline.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"Randomised" but method otherwise not described
Allocation concealment (selection bias)	Unclear risk	Method not described
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Blinding not stated
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Blinding not stated
Incomplete outcome data (attrition bias) All outcomes	Low risk	Losses to follow‐up: 2/32 – 1 woman in the control group with a fetal death; 1 woman (group not specified) gave birth before her scheduled procedure
Selective reporting (reporting bias)	Unclear risk	Unclear reporting
Other bias	Unclear risk	Unclear reporting