The effect of scheduled metamizole on opioid consumption after cardiac surgery

Area of Science:

• Anesthesiology
• Pharmacology
• Cardiovascular Surgery

Background:

• Postoperative pain management after cardiac surgery is complex, often requiring multimodal analgesia.
• Opioid-based analgesia carries risks, including respiratory depression and prolonged dependence.
• Optimizing non-opioid analgesics is crucial for enhancing patient recovery and safety.

Purpose of the Study:

• To evaluate the impact of a standardized scheduled metamizole dosing protocol on postoperative pain management.
• To assess the opioid-sparing effect and safety profile of scheduled metamizole in cardiac surgery patients.
• To compare pain scores and opioid consumption before and after protocol implementation.

Main Methods:

• Retrospective study design.
• Implementation of a standardized scheduled metamizole dosing protocol within a multimodal analgesia strategy.
• Analysis of pain scores (Numeric Rating Scale) and opioid consumption (morphine equivalents).
• Assessment of safety outcomes, including agranulocytosis, neutropenia, and renal function (serum creatinine).

Main Results:

• Scheduled metamizole was associated with significantly lower opioid consumption (119.51 to 95.91 mg morphine equivalents, p < 0.0001).
• Pain scores improved significantly post-protocol (1.12 to 0.89, p < 0.0001).
• No clinically significant adverse events like agranulocytosis or neutropenia were observed; renal function remained stable.

Conclusions:

• Scheduled metamizole is a safe and effective opioid-sparing agent for postoperative pain management in cardiac surgery.
• The protocol demonstrated efficacy in reducing opioid requirements while maintaining adequate pain control.
• Further prospective studies are recommended to validate findings and optimize dosing strategies.