Use of alfentanil for in vitro fertilization oocyte retrieval

Pain Management during Ultrasound Guided Transvaginal Oocyte Retrieval - A Narrative Review

Transvaginal oocyte retrieval (TVOR), done for the purpose of assisted reproduction can instigate enormous pain and therefore requires adequate analgesia with the least adverse effects. As the procedure involves retrieving oocytes for in vitro fertilisation, the effect of the anaesthetic drugs on the oocyte quality should also be considered. This review focuses on the various modes of anaesthesia and the anaesthetic drugs which can be administered safely to provide effective analgesia in normal and in special conditions such as women with pre-existing comorbidities. Medline, Embase, PubMed and Cochrane electronic databases were searched according to modified Preferred Reporting Items for Systemic Reviews and Meta-Analyses guidelines. According to this review, conscious sedation appears to be the most preferred mode of anaesthesia in women undergoing TVOR owing to fewer adverse effects, faster recovery, better patient and specialist comfort and the least effect on oocyte quality and embryo development. Combining it with paracervical block resulted in lesser consumption of the anaesthetic drug, which may have a beneficial effect on the oocyte quality.

Effect of alfentanil dosage during oocyte retrieval on fertilization and embryo quality

OBJECTIVE

A possible negative effect of pain-relieving analgesics used during oocyte retrieval on fertilization and embryo development has been discussed. This study examines whether alfentanil dosage adversely affects fertilization and/or embryo quality.

STUDY DESIGN

In a retrospective observational study the effect of different doses of alfentanil on two primary endpoints, fertilization rate and good quality embryo (GQE) rate, were compared in 663 women.

RESULTS

In group A (<or=0.5mg alfentanil) and group B (>0.5mg alfentanil) mean fertilization rate was 0.6+/-0.3 versus 0.6+/-0.2 (P=0.678, adjusted P=0.937, 95% CI for the difference -0.041; 0.044) and mean GQE rate was 0.6+/-0.3 versus 0.5+/-0.3 (P=0.207, adjusted P=0.179, 95% CI for the difference -0.015; 0.078), respectively. A paired comparison of 65 women who underwent repeated IVF cycles found that, compared with <or=0.5mg alfentanil, doses of >0.5mg alfentanil had no adverse effects on fertilization rate (mean difference 0.05+/-0.3, P=0.231, 95% CI -0.02; 0.12) or GQE rate (mean difference -0.02+/-0.4, P=0.970, 95% CI -0.12; 0.09).

CONCLUSION

The amount of alfentanil is not associated with adverse effects on fertilization rate, embryo development, or clinical pregnancy rate, which is reassuring and indicates that women can be offered adequate pain relief.

Anesthesia for in vitro fertilization: the addition of fentanyl to 1.5% lidocaine

Ultrasonically guided transvaginal oocyte retrieval is relatively short procedure that is performed on an out-patient basis. The optimal anesthetic technique should allow good surgical anesthesia with minimal side effects, a short recovery time, and, if possible, a high rate of successful pregnancy. Spinal anesthesia is often used in this institution, as well as many others, for this procedure. The addition of fentanyl may be effective for both intraoperative and postoperative pain relief. We assessed the effect of adding fentanyl to 1.5% lidocaine in women undergoing ultrasonically guided oocyte retrieval. Seventy-eight women were randomized to receive 45 mg of hyperbaric 1.5% lidocaine with or without 10 microg of fentanyl. Visual analog scale (VAS) pain scores were lower in the operating room (OR) (P < 0.05) and postanesthesia care unit (PACU) (P < 0.0005) for the group that received fentanyl. In addition, the amount of narcotic required in the PACU was less in the fentanyl group (P < 0.005). There was no difference in VAS scores the evening of or 24 h after the procedure. The amount of analgesics and narcotics required after discharge was the same for both groups. Timed variables, such as time to urination, ambulation, and discharge, were the same for both groups of women. The addition of fentanyl to lidocaine for transvaginal oocyte retrieval results in a more comfortable patient in the OR and PACU.

IMPLICATIONS

This study demonstrates that when fentanyl is added to a local anesthetic, lidocaine, with spinal anesthesia for egg retrieval procedures, patients are more comfortable during the procedure compared with those who receive lidocaine alone. In addition, the narcotic requirements of patients are less in the postanesthesia care unit.