Background: Remifentanil for pain relief during labour is alternative to epidural analgesia. The aim is to highlight rare serious complication of labour analgesia with remifentanil and describe its solution in the hospital, where the use of remifentanil in childbirth is analgesic method of choice. 

Case Report: 26-years old primigravida nullipara in the 39th week of pregnancy, height 160 cm, weight 70 kg (BMI 29 kg/m2). History of three acute meningitis, two herpes infections and polyvalent allergy. During her adolescence, she abused marijuana followed by 6 hours of unconsciousness. One year before pregnancy, she underwent short-term general anaesthesia as part of donating oocytes without complications. The pregnancy was uncomplicated. She asked for labour analgesia after 7 hours from labour initiation. Blood pressure at the time of indication was 130/90 mmHg, pulse 116/min, SpO2 95%, and pain intensity according to VAS 8. Remifentanil administration was initiated at a rate of 3.2 mL/hr IV (80 μg/hr) without PCA boluses. After ten minutes of infusion, blood pressure was 115/75 mmHg, pulse 105/min, SpO294%, and VAS decreased to 6-7. After 13 minutes of the infusion the obstetrician was called for her loss of consciousness by her partner. Physician called the anaesthetic team. The parturient was cyanotic (SpO2not detected), GCS 3, and the pulse was not palpable on the carotid arteries, and masseteric muscles rigidity was present. Remifentanil infusion was immediately stopped. Cardiopulmonary resuscitation was started and naloxone 0.4 mg IV was administered.  Parturient awakened in tens seconds after administration of naloxone to full lucidity (GCS 15). Return of spontaneous circulation was achieved in 3 minutes. Acute caesarean section was performed in general anaesthesia without complications. The newborn was male, 2730g, 49cm with Apgar score 10-10-10.

Discussion: We computed plasmatic level of remifentanil during administration with maximum level of 0.6 ng/mL (TIVA trainer, Minto model). This level is far from the level that, according to available literature, causes 50% depression of minute ventilation in healthy volunteers 1.17 μg/mL (0.85-1.49 ng/mL)1.

Conclusion: Case report pointed out the need for availability of remifentanil antidote in the delivery room and the importance of rapid availability of anaesthetic team.

1. Glass et al. Anesthesiology, 1999

Learning points: naloxone availability; rapid response emergency team

02 / Successful Naloxone Administration During Cardiac Arrest in Course of Remifentanil Labor Analgesia: Case Report