Meperidine

IntroductionMild therapeutic hypothermia has been shown to improve outcome for patients after cardiac arrest and may be beneficial for ischaemic stroke and myocardial ischaemia patients. However, in the awake patient, even a small decrease of core temperature provokes vigorous autonomic reactions-vasoconstriction and shivering-which both inhibit efficient core cooling. Meperidine and skin warming each linearly lower vasoconstriction and shivering thresholds. We tested whether a combination of skin warming and a medium dose of meperidine additively would reduce the shivering threshold to below 34 degrees C without producing significant sedation or respiratory depression.MethodsEight healthy volunteers participated on four study days: (1) control, (2) skin warming (with forced air and warming mattress), (3) meperidine (target plasma level: 0.9 mug/ml), and (4) skin warming plus meperidine (target plasma level: 0.9 mug/ml). Volunteers were cooled with 4 degrees C cold Ringer lactate infused over a central venous catheter (rate asymptotically equal to 2.4 degrees C/hour core temperature drop). Shivering threshold was identified by an increase of oxygen consumption (+20% of baseline). Sedation was assessed with the Observer's Assessment of Alertness/Sedation scale.ResultsControl shivering threshold was 35.5 degrees C +/- 0.2 degrees C. Skin warming reduced the shivering threshold to 34.9 degrees C +/- 0.5 degrees C (p = 0.01). Meperidine reduced the shivering threshold to 34.2 degrees C +/- 0.3 degrees C (p ConclusionA combination of meperidine and skin surface warming reduced the shivering threshold to 33.8 degrees C +/- 0.2 degrees C via an additive interaction and produced only very mild sedation and no respiratory toxicity.

BackgroundBronchoscopy can be a distress for the patient. There have been few studies on the combination of sedatives and opioids. The aim of this study was to demonstrate the usefulness and safety of administration of the combination of midazolam and pethidine during bronchoscopy.MethodsIn this prospective randomized single (patient)-blind study, we randomly assigned 100 patients who were scheduled to undergo bronchoscopy biopsy to receive treatment with either the midazolam/pethidine combination (combination group) or midazolam alone (midazolam group) during examinations. After the end of bronchoscopy, patients completed a questionnaire and the visual analogue scale was measured. The primary outcome was the patients' acceptance of re-examination assessed by visual analogue scale. We also assessed pain levels, vital signs, midazolam use, xylocaine use, and adverse events. Univariate analyses were performed using Fisher's exact test for categorical data, and the t-test or Mann-Whitney test was carried out for analysis of numeric data. All P-values were two-sided, and values ResultsWe analyzed 47 patients in the combination group and 49 patients in the midazolam group. The primary outcome was a good trend in the combination group, but not significantly different (3.82 ± 2.3 in combination group versus 4.17 ± 2.75 in midazolam alone, P = 0.400). In the combination group, the visual analog scale score for pain during bronchoscopy was significantly lower (1.10 ± 1.88 versus 2.13 ± 2.42, P = 0.022), and the sedation level score per the modified observer's assessment of alertness/sedation scale was significantly deeper (3.49 ± 0.98 versus 3.94 ± 1.03, P = 0.031). Maximal systolic blood pressure during testing was significantly lower (162.39 ± 23.45 mmHg versus 178.24 ± 30.24 mmHg, P = 0.005), and the number of additional administrations of midazolam was significantly lower (2.06 ± 1.45 versus 2.63 ± 1.35, P = 0.049). There were also significantly fewer adverse events (30 versus 41, P = 0.036).ConclusionsThe combination uses of midazolam and pethidine for sedation resulted in significant improvements in the pain, blood pressure, additional use of midazolam, and safety during bronchoscopy among patients.Trial registrationThis study was registered in the University Medical Hospital Information Network in Japan (UMINCTR Registration number: UMIN000032230 , Registered: 13/April/2018).

BackgroundThe commonest opioid used for pain relief in labour is pethidine (meperidine); however, its effectiveness has long been challenged and the drug has known side effects including maternal sedation, nausea and potential transfer across the placenta to the foetus. Over a third of women receiving pethidine require an epidural due to inadequate pain relief. Epidural analgesia increases the risk of an instrumental vaginal delivery and its associated effects. Therefore, there is a clear need for a safe, effective, alternative analgesic to pethidine. Evidence suggests that remifentanil patient-controlled analgesia (PCA) reduces epidural conversion rates compared to pethidine; however, no trial has yet investigated this as a primary endpoint. We are, therefore, comparing pethidine intramuscular injection to remifentanil PCA in a randomised controlled trial.Methods/designWomen in established labour, requesting systemic opioid pain relief, will be randomised to either intravenously administered remifentanil PCA (intervention) or pethidine intramuscular injection (control) in an unblinded, 1:1 individual randomised trial. Following informed consent, 400 women in established labour, who request systemic opioid pain relief, from NHS Trusts across England will undergo a minimised randomisation by a computer or automated telephone system to either pethidine or remifentanil. In order to balance the groups this minimisation is based on four parameters; parity (nulliparous versus multiparous), maternal age (DiscussionThe RESPITE trial's primary outcome is the proportion of women who have an epidural placed for pain relief in labour in each arm.Trial registrationCurrent Controlled Trials registration number: ISRCTN29654603 . Registered on 23 July 2013.

BackgroundIntravenous lidocaine has shown promise as an effective analgesic in various clinical settings, but its utility for pain management in emergency departments, especially for bone fractures, remains relatively understudied.ObjectiveThis study compared intravenous lidocaine to pethidine for femoral bone fracture pain management.MethodsThis double-blind, randomized, controlled clinical trial was conducted in the emergency department of AJA University of Medical Sciences affiliated hospitals. Patients aged 18-70 years-old with femoral bone fracture and experiencing severe pain, defined as a numerical rating scale (NRS) of pain ≥ 7, were included in the study. One group received intravenous pethidine (25 mg), while the other group received intravenous lidocaine (3 mg/kg, not exceeding 200 mg), infused with 250 ml saline over 20 min. Pain levels were evaluated before treatment administration (0 min) and at 10, 20, 30, 40, 50, and 60 min after treatment administration using the NRS.ResultsSeventy-two patients were enrolled in the study. Demographic characteristics and pain scores were similar between the two groups. The mean pain scores upon arrival for the lidocaine and pethidine groups were 8.50 ± 1 and 8.0 ± 1, respectively; after one hour, they were 4.0 ± 1 and 4.0 ± 1, respectively. While there was a statistically significant reduction in pain in both groups after one hour, there were no clinically or statistically significant differences between the two groups (p = 0.262). Pethidine had a higher incidence of adverse events, though not statistically significant. Additionally, females required more rescue analgesics.ConclusionThe administration of intravenous lidocaine is beneficial for managing pain in femoral bone fractures, suggesting that lidocaine could be a potent alternative to opioids.Trial registrationIRCT20231213060355N1 ( https://irct.behdasht.gov.ir/trial/74624 ) (30/12/2023).