Efficacy and Safety of Intravenous Tramadol versus Intravenous Paracetamol for Relief of Acute Pain of Primary Dysmenorrhea: A Randomized Controlled Trial

Comparison of intravenous paracetamol (acetaminophen) to intravenously or intramuscularly administered non-steroidal anti-inflammatory drugs (NSAIDs) or opioids for patients presenting with moderate to severe acute pain conditions to the ED: systematic review and meta-analysis

OBJECTIVE

Paracetamol, non-steroidal anti-inflammatory drugs (NSAIDs) and opiates/opioids, administered parenterally via intravenous or intramuscular route, are widely used to provide analgesia for patients with moderate to severe pain. This systematic review and meta-analysis evaluated the level of analgesia provided by intravenous paracetamol (IVP) alone compared with NSAIDs (intravenous or intramuscular), or opioids (intravenous) alone in adults attending the ED with acute pain.

METHODS

Two authors independently searched PubMed (MEDLINE), Web of Science, Embase (OVID), Cochrane Library, SCOPUS and Google Scholar (3 March 2021-20 May 2022) for randomised trials without any language or date restriction. Clinical trials were evaluated using the Risk of Bias V.2 tool. The primary outcome was mean difference (MD) for pain reduction at 30 min (T30) post analgesia delivery. The secondary outcomes were MD in pain reduction at 60, 90 and 120 min; the need for rescue analgesia; and the occurrence of adverse events (AEs).

RESULTS

Twenty-seven trials (5427 patients) were included in the systematic review and 25 trials (5006 patients) in the meta-analysis. There was no significant difference in pain reduction at T30 between the IVP group and opioids (MD -0.13, 95% CI -1.49 to 1.22) or IVP and NSAIDs (MD -0.27, 95% CI -1.0 to 1.54. There was also no difference at 60 min, IVP group versus opioid group (MD -0.09, 95% CI -2.69 to 2.52) or IVP versus NSAIDs (MD 0.51, 95% CI 0.11 to 0.91). The quality of the evidence using Grading of Recommendations, Assessments, Development and Evaluations methodology was low for MD in pain scores.The need for rescue analgesia at T30 was significantly higher in the IVP group compared with the NSAID group (risk ratio (RR): 1.50, 95% CI 1.23 to 1.83), with no difference found between the IVP group and the opioid group (RR: 1.07, 95% CI 0.67 to 1.70). AEs were 50% lower in the IVP group compared with the opioid group (RR: 0.50, 95% CI 0.40 to 0.62), whereas no difference was observed in the IVP group compared with the NSAID group (RR: 1.30, 95% CI 0.78 to 2.15).

CONCLUSION

In patients presenting to the ED with a diverse range of pain conditions, IVP provides similar levels of pain relief compared with opiates/opioids or NSAIDs at T30 post administration. Patients treated with NSAIDs had lower risk of rescue analgesia, and opioids cause more AEs, suggesting NSAIDs as the first-choice analgesia and IVP as a suitable alternative.

PROSPERO REGISTRATION NUMBER

CRD42021240099.

Moxibustion for Primary Dysmenorrhea: An Adjuvant Therapy for Pain Relief

The latest spectrum of moxibustion disease shows that primary dysmenorrhea is a high-frequency symptom of moxibustion and that it is the dominant clinical disease. In the specific treatment methods, all types of moxibustion methods have been widely used, such as thermal, thunder fire, partitioned, and spreading moxibustion. Moxibustion plays a therapeutic role through its four mechanisms of action: heat, light, moxa smoke, and drug effects. The mechanism of moxibustion treatment for primary dysmenorrhea focuses on adjusting endocrine hormones, regulating immune function and neuro-related factors, and improving uterine microcirculation. In this study, based on the clinical evidence of different moxibustion methods for treating primary dysmenorrhea, the design model, intervention characteristics, and clinical outcomes were analyzed. Meanwhile, the brain effect mechanisms of different imaging methods were summarized from the perspective of neuroimaging. It was pointed out that the left anterior cingulate gyrus, left inferior parietal angular gyrus, and left superior gyrus may be the analgesic brain regions that regulate sensory, emotional, and cognitive aspects. Moreover, the neural circuits involved can be inferred: the frontal cortex-basal ganglia (the pea nucleus)-cerebral cortex, which mediates motivation and emotional drive, and the parietal lobe-basal ganglia-limbic lobe-frontal lobe, which is involved in neurotransmitter transport and emotional regulation and behavioral expression. There are still problems and deficiencies in studies on the mechanism of moxibustion treatment for primary dysmenorrhea. Studies should be strengthened on how moxibustion produces an effect. Attention should be paid to exploring how the spectrum range and peak in the light effect of moxibustion treat primary dysmenorrhea. Studies assessing the mechanisms of moxibustion treatment for primary dysmenorrhea should be conducted to provide an experimental basis and evidence-based medical evidence for clinical treatment.