Metamizole in perioperative treatment in children under 14 years – results of a questionnaire survey from practice

Questionnaire Survey

The survey was conducted via an online questionnaire sent to members of the German Society of Anesthesiology and Intensive Care Medicine and the German Pain Society. The questionnaire was completed by 1476 physicians involved in the treatment of children under 14 years. A total of 90.5% were from Germany, but experts from Austria, Switzerland, and the Netherlands also participated.

Use of Metamizole

Non-opioid analgesics are used in perioperative care by 99.1% of respondents: 83.9% non-steroidal anti-inflammatory drugs (NSAIDs), 68.6% metamizole, 67.5% paracetamol, and 2% cyclooxygenase-2 (COX-2) inhibitors. Intravenous metamizole was the most commonly used analgesic during surgery. In the postoperative period, German anesthesiologists use metamizole, NSAIDs, and paracetamol equally. In cases of severe pain, 49.3% of respondents use metamizole in combination with another non-opioid analgesic, 14.8% administer it as monotherapy, and 23.2% have never used it.

Advertisement:

Dosage

Regarding dosage, most physicians administer intravenous metamizole at a maximum dose of 15 mg/kg, with 26% administering doses of 16–20 mg/kg. The duration of metamizole use is limited by 20.2% of respondents, ranging from a single dose to administration for up to 2 weeks.

Safety

Two-thirds of physicians did not report any adverse events with metamizole administration. 3–4% of respondents observed allergic/anaphylactic reactions or a drop in blood pressure. 73.1% of respondents did not detect any change in leukocyte count in children treated with metamizole, while agranulocytosis was recorded by 0.14% of physicians, usually as an incidental finding. However, no serious consequences of this condition were detected. Routine blood count monitoring during metamizole treatment is performed by only 5.5% of physicians. Possible side effects are occasionally communicated to the treated child's parents by 6.1% of respondents and always by only 3.5% of them.

Conclusion

This survey among German-speaking physicians showed that metamizole is a frequently used non-opioid analgesic in perioperative care for children under 14 years. It is the preferred analgesic in prophylactic pain treatment administered intraoperatively. However, it is necessary to monitor clinical signs of agranulocytosis and inform patients and their parents about them in advance.

(zza)

Source: Witschi L., Reist L., Stammschulte T. et al. Perioperative use of metamizole and other nonopioid analgesics in children: results of a survey. Anaesthesist 2019 Mar; 68 (3): 152–160, doi: 10.1007/s00101-018-0532-4.