Anaesthesia for assisted conception: a survey of UK practice.

A telephone survey was undertaken of all UK centres (total 70) licensed for performing in vitro fertilization (IVF) and gamete intra-fallopian transfer (GIFT) by the Human Fertilisation and Embryology Authority (HFEA). The survey was carried out during the months of November and December 1997. Thirty-seven (52.1%) centres were in the NHS sector and 33 (47.8%) in the private sector. A response was available from 60 (84%) centres. A standard questionnaire was used which requested information about the procedures carried out, anaesthetic technique and pharmacological agents used. Forty-seven centres carried out IVF, two centres GIFT and 11 centres both. Out of 58 centres carrying out IVF, sedation was used in 28, general anaesthesia in 17, sedation combined with regional anaesthesia in seven and regional anaesthesia in one. Five centres gave a choice. Out of 22 centres using general anaesthesia for IVF, 12 used inhalational agents (isoflurane eight, enflurane four, sevoflurane two), eight used total intravenous anaesthesia (TIVA) with propofol and two centres inhalational agents or TIVA. Propofol was the induction agent in all but two centres. For IVF under sedation, 18 centres used midazolam, five used diazepam, three used opioids, one used entonox and the remaining ones a combination. When sedation was combined with regional anaesthesia, four centres used midazolam, two used propofol, one used midazolam with propofol, one used opioids and one used entonox. The regional technique in the 11 centres was either paracervical block with lignocaine (eight) or subarachnoid block with bupivacaine (three). Systemic analgesia was secured with fentanyl (22), pethidine (16), alfentanil (15), diclofenac (14), piroxicam (two), ketorolac (one) and ibuprofen (one). Five centres did not use any opioids; 40 centres did not use any nonsteroidal agents (NSAIDs). Out of the 13 centres that carried out GIFT, 12 used general anaesthesia while the thirteenth gave the patient a choice between general or regional anaesthesia. 11 centres used inhalational agents (isoflurane nine, enflurane two) while two used TIVA with propofol; propofol was the induction agent used in six centres while thiopentone was used in five. The range of analgesics was wide--fentanyl in six centres, alfentanil in three, morphine in two, diclofenac in five and ketorolac in one. Two centres did not use any opioids and seven centres did not use an NSAID. The only agreement at present appears to be that halothane is an unwise choice for IVF. No other technique has yet been proven to be either advantageous or detrimental.