Copyright © European Society of Anaesthesiology. Unauthorized reproduction of this article is prohibited. A randomised comparison of the effects of low-dose spinal or general anaesthesia on umbilical cord blood gases during caesarean delivery of growth-restricted foetuses with impaired Doppler flow Kajal Jain, Neerja Bhardwaj, Anchal Sharma, Jaswinder Kaur and Praveen Kumar Context Hypotension following spinal anaesthesia for caesarean delivery may decrease uteroplacental perfusion and produce foetal acidosis. The optimal anaesthetic technique for mothers with foetal growth restriction and impaired Doppler flow is unclear. Objective To compare the effects of low-dose spinal anaesthesia and general anaesthesia on neonatal outcome and maternal haemodynamics. Design Prospective, randomised clinical trial. Setting Tertiary care hospital. Patients Forty pregnant women with foetal growth restriction and impaired Doppler flow scheduled for elective caesarean delivery. Interventions The women were allocated randomly to receive a low-dose spinal anaesthetic (8-mg hyperbaric bupivacaine 0.5% with fentanyl 20 mg) or standard general anaesthesia for elective caesarean delivery. SBP was maintained between 80 and 100% of baseline using bolus doses of phenylephrine. The total duration of hypotension, dose of phenylephrine used and any incidence of hypotension, nausea or vomiting were recorded. Main outcome measures The primary outcome variable was arterial and venous umbilical cord base deficit. Neonatal outcome and maternal haemodynamics were analysed as secondary endpoints. Results The mean umbilical artery pH was significantly lower in the low-dose spinal anaesthesia group than in the general anaesthesia group (7.23  0.06 vs. 7.27  0.04, P ¼ 0.01). Cord base deficit was similar in the two groups. Higher partial pressures of oxygen occurred in the general anaesthesia group (20.9  6.5kPa) than in the low-dose spinal anaesthesia group (13.6  6.1 kPa, P ¼ 0.001). No difference was observed between groups in 1 and 5-min Apgar scores. There appeared to be a greater need for immediate resuscitation of neonates in the general anaesthesia group, but the difference was not statistically significant (P ¼ 0.51). Low-dose spinal anaesthesia was associated with hypotension of short duration (0.7  1.1 min). Conclusion In this study, there was no difference in umbilical cord base deficit between the groups. Larger studies would be required to assess whether the mode of anaesthesia influences the incidence of clinically important neonatal acidosis in neonates with foetal growth restriction. Eur J Anaesthesiol 2013; 30:9–15 Published online 6 September 2012 Keywords: anaesthesia, fetal growth restriction, general, spinal Introduction Subarachnoid block (SAB) is considered simpler and safer than other techniques of anaesthesia for caesarean delivery and is, therefore, the technique of choice of most anaesthesiologists. Current evidence suggests that it may not be safer than general or epidural anaesthesia for foetal wellbeing. 1–4 Maternal hypo- tension following SAB may potentially decrease utero- placental perfusion, leading to foetal acidosis. However, studies have shown that this is not an issue when hypotension is treated promptly with phenylephrine or when it is used prophylactically to prevent hypotension induced by spinal anaesthesia. 5,6 Further, as the newborns are generally vigorous, foetal acidosis may not be of concern in healthy, term parturient women; however, in situations of uteroplacental insufficiency with growth- restricted foetuses, the effect of SAB on neonatal outcome may be detrimental. 2–4,7 Chronic uteroplacental insufficiency decreases foetal physiological reserve and, therefore, increases the risk of intrapartum asphyxia. Hence, small changes in perfusion for even a short duration may produce signifi- cant changes in foetal blood gas values. 7 Doppler velocimetry studies demonstrate abnormal flow velocity in the umbilical arteries, suggesting severe placental dysfunction with foetal growth restriction (FGR) and ORIGINAL ARTICLE From the Department of Anaesthesia and Intensive Care (KJ, NB, AS), Department of Obstetrics and Gynaecology (JK), Department of Paediatric Medicine (PK), Postgraduate Institute of Medical Education and Research, Chandigarh, and All India Institute of Medical Sciences, New Delhi (AS), India Correspondence to Kajal Jain, Department of Anaesthesia and Intensive Care, Postgraduate Institute of Medical Education and Research, Chandigarh, 1600012, India Fax: +91 172 2744401/2745078; e-mail: kajalteji@gmail.com This report was previously presented, in part, at the Annual Conference of the Indian Society of Anaesthetists; December 2008; Jodhpur, Rajasthan, India. This article is accompanied by the following Invited Commentary: Habib AS. Anaesthesia for caesarean delivery of growth-restricted foetuses: a bird in the hand is worth two in the bush. Eur J Anaesthesiol 2013; 30:5–6. 0265-0215 ß 2012 Copyright European Society of Anaesthesiology DOI:10.1097/EJA.0b013e3283564698