Metamizol and diclofenac profoundly reduce opioid consumption after minor trauma surgery

Metamizole Use in Children: Analysis of Drug Utilisation and Adverse Drug Reactions at a German University Hospital between 2015 and 2020

BACKGROUND

Metamizole use is controversially discussed due to its potentially serious adverse drug reactions (ADRs). In Germany, however, it remains a popular analgesic and antipyretic drug.

OBJECTIVE

The aim of this study was to discuss the safety profile of metamizole in children by analysing the inpatient prescription patterns and presenting the metamizole-related ADRs at a paediatric hospital between 2015 and 2020.

METHODS

Metamizole utilisation data were retrospectively analysed from electronic medical records. ADRs were prospectively recorded via the hospital's stimulated reporting system and analysed accordingly. Patients aged < 18 years admitted to one of the general wards of the department of paediatrics and adolescent medicine of a German university hospital between June 2015 and May 2020 who received at least one drug therapy within their inpatient stay were included in the analysis. Causality of ADRs was rated according to the World Health Organisation causality assessment.

RESULTS

In 31.7% (3759/11,857) of the inpatient stays of 7809 patients, metamizole was administered. Metamizole exposure was highest in adolescents (37.9%) and lowest in newborns (9.9%). Overall, metamizole was administered parenterally in about 90%. Three cases of agranulocytosis, one allergic shock and one rash with possible or higher causality to metamizole treatment were reported. Three of these occurred prior to hospitalisation. All patients recovered without remaining harm.

DISCUSSION

Metamizole is commonly used in paediatric inpatients in Germany. Serious ADRs occur but rarely. Continuous monitoring of drug therapy through, for example, stimulated reporting systems ensures that serious ADRs are detected, and appropriate interventions can be introduced.

Postoperative pain management in children: Guidance from the pain committee of the European Society for Paediatric Anaesthesiology (ESPA Pain Management Ladder Initiative)

The main remit of the European Society for Paediatric Anaesthesiology (ESPA) Pain Committee is to improve the quality of pain management in children. The ESPA Pain Management Ladder is a clinical practice advisory based upon expert consensus to help to ensure a basic standard of perioperative pain management for all children. Further steps are suggested to improve pain management once a basic standard has been achieved. The guidance is grouped by the type of surgical procedure and layered to suggest basic, intermediate, and advanced pain management methods. The committee members are aware that there are marked differences in financial and personal resources in different institutions and countries and also considerable variations in the availability of analgesic drugs across Europe. We recommend that the guidance should be used as a framework to guide best practice.

Metamizole (dipyrone) effects on sevoflurane requirements and postoperative hyperalgesia in rats

Unlike non-steroidal anti-inflammatory drugs (NSAIDs), metamizole has poor anti-inflammatory effects; and is suitable for models where analgesia, but not anti-inflammatory effects, is desirable. Like opioids, these drugs produce perioperative analgesia while reducing anaesthetic requirements, but it remains unclear whether they may develop tolerance or hyperalgesia, and thus decrease in analgesic efficacy. The aim was to determine whether tolerance or hyperalgesia to metamizole occurred in rats, and whether the sevoflurane minimum alveolar concentration (MAC) was affected. In a randomized, prospective, controlled study, male Wistar rats ( n = 8 per group) were administered metamizole (300 mg/kg, day 4). Previously, the following treatments were provided: daily metamizole for four days (0-3), morphine (10 mg/kg; positive control, day 0 only) or saline (negative control). The main outcome measures were mechanical (MNT) and warm thermal (WNT) nociceptive quantitative sensory thresholds. The baseline sevoflurane MAC and the reduction produced by the treatments were also determined. The mean (SD) baseline MAC [2.4(0.2)%vol] was decreased by morphine and metamizole by 45(11)% and 33(7)% ( P = 0.000, both), respectively. Baseline MNT [35.4(4.5) g] and WNT [13.2(2.4) s] were decreased by morphine and metamizole: MNT reduction of 22(6)% ( P = 0.000) and 22(7)% ( P = 0.001), respectively and WNT reduction of 34(14)% ( P = 0.000) and 24(13)% ( P = 0.001). The baseline MAC on day 4 was neither modified by treatments nor the MAC reduction produced by metamizole (days 0 and 4; P > 0.05). In conclusion, repeated metamizole administration may produce hyperalgesia, although it may not modify its anaesthetic sparing effect. The clinical relevance of this effect in painful research models requiring prolonged analgesic therapy warrants further investigation.

[Pediatric perioperative systemic pain therapy: Austrian interdisciplinary recommendations on pediatric perioperative pain management]

BACKGROUND

Many analgesics used in adult medicine are not licensed for pediatric use. Licensing limitations do not, however, justify that children are deprived of a sufficient pain therapy particularly in perioperative pain therapy. The treatment is principally oriented to the strength of the pain. Due to the degree of pain caused, intramuscular and subcutaneous injections should be avoided generally.

NON-OPIOIDS

The basis of systemic pain therapy for children are non-opioids and primarily non-steroidal anti-inflammatory drugs (NSAIDs). They should be used prophylactically. The NSAIDs are clearly more effective than paracetamol for acute posttraumatic and postoperative pain and additionally allow economization of opioids. Severe side effects are rare in children but administration should be carefully considered especially in cases of hepatic and renal dysfunction or coagulation disorders. Paracetamol should only be taken in pregnancy and by children when there are appropriate indications because a possible causal connection with bronchial asthma exists. To ensure a safe dosing the age, body weight, duration of therapy, maximum daily dose and dosing intervals must be taken into account. Dipyrone is used in children for treatment of visceral pain and cholic. According to the current state of knowledge the rare but severe side effect of agranulocytosis does not justify a general rejection for short-term perioperative administration.

OPIOIDS

In cases of insufficient analgesia with non-opioid analgesics, the complementary use of opioids is also appropriate for children of all age groups. They are the medication of choice for episodes of medium to strong pain and are administered in a titrated form oriented to effectiveness. If severe pain is expected to last for more than 24 h, patient-controlled anesthesia should be implemented but requires a comprehensive surveillance by nursing personnel.

KETAMINE

Ketamine is used as an adjuvant in postoperative pain therapy and is recommended for use in pediatric sedation and analgosedation.

Efficacy of lornoxicam for acute postoperative pain relief after septoplasty: a comparison with diclofenac, ketoprofen, and dipyrone

STUDY OBJECTIVES

To compare the efficacy of injectable lornoxicam with diclofenac, ketoprofen, and dipyrone for acute postoperative pain.

DESIGN

Prospective, randomized, placebo-controlled, double-blind study.

SETTING

University hospital.

PATIENTS

200 ASA physical status I patients who were scheduled for elective septoplasty with general anesthesia.

INTERVENTIONS

Patients were divided into 5 groups according to the intramuscularly administered analgesic drug: lornoxicam 8 mg (twice daily), diclofenac 75 mg (twice daily), ketoprofen 100 mg (twice daily), dipyrone 1 g (three times daily), and placebo (twice daily).

MEASUREMENTS

Pain intensity was evaluated with a 0 to 100 mm Visual Analog Scale (VAS) at the 2nd, 4th, 6th, 8th, 12th, 16th, 20th, and 24th hour postoperatively. Intramuscular pethidine 1 mg/kg was administered to patients requiring additional analgesia, and treatment-related adverse effects were noted.

MAIN RESULTS

Pethidine requirement was found to be significantly higher in the placebo group (1.8 mg/kg per 24 hours; 95% confidence interval, 1.5-2.2) than in the other groups (P = 0.001). No significant difference in opioid requirement was found among the treated groups (P > 0.05). Postoperative VAS scores were significantly lower at specific hours in the treatment groups when compared with placebo group (P < 0.05). No statistically significant difference in adverse effects was found among the groups studied (P > 0.05).

CONCLUSIONS

Efficacy of lornoxicam in the management of acute postoperative pain was not superior to that of other nonopioid analgesics used in this study.

[Drugs for postoperative analgesia: routine and new aspects. Part 1: non-opioids]

In part 1 of this review the perioperative aspects of the use of non-opioids (acetaminophen, dipyrone, traditional NSAR, coxibs) and in part 2 of opioids (weak opioids: tramadol, tilidine with naloxone, strong opioids: morphine, piritramide, oxycodone, hydromorphone, fentanyl, methadone, buprenorphine) and coanalgesics (gabapentinoids, ketamine) will be discussed. The main aim is to describe the relationship between analgesic efficacy and side effects to make clinical decisions easier in patients with preoperative renal, gastrointestinal, cardiovascular and other diseases. Some new aspects concerning perioperative administration of gabapentinoids and ketamine in patients with perioperative neuropathic pain are discussed.

Analgetikakombinationen zur postoperativen Schmerztherapie

BACKGROUND

The supplementation of an opioid by a non-opioid analgesic is a widely accepted technique for the treatment of postoperative pain. However, it is still unclear whether a combination of different non-opioids has an advantage in terms of an improved analgesia and/or a reduction of the opioid-related adverse effects.

METHODOLOGY

A systematic analysis of the literature was performed searching for randomized, controlled trials studying the effects of a combination of two non-opioid analgesics in order to reduce postoperative opioid requirements and/or postoperative pain. Significant reduction of the postoperative opioid requirement and/or postoperative pain were defined as main rating criteria. To facilitate comparisons between the trials, the relative (proportional) reduction of postoperative opioid administration and the relative reduction of postoperative pain were calculated on defined pain scales.

RESULTS

A total of 25 trials were identified, mainly studies comparing non-steroidal anti-inflammatory drugs (NSAIDs) with paracetamol. Only 3 trials found a statistically improved analgesic efficacy and 15 studies did not show any relevant improvement or the combination group was only significantly superior to one of the groups receiving monotherapy. A further seven studies could not be evaluated due to methodological issues. There was no evidence for a significant reduction of opioid-induced adverse effects.

CONCLUSION

A combination of non-opioid analgesics, in particular NSAIDs with paracetamol, cannot be recommended at present due to the lack of data showing improved effectiveness.