Epidural pethidine and bupivacaine in labour

A double-blind randomised study was performed to assess the value of the addition of pethidine 50 mg to the initial dose of bupivacaine given for epidural analgesia in labour. Forty-nine patients received either 1 ml of saline (n = 24), or 50 mg of pethidine (n = 25), added to 9 ml of 0.25% bupivacaine as an initial injection for intrapartum epidural analgesia. There was a significant increase in the mean duration of analgesia in the pethidine group. However, pethidine did not increase the speed of onset of analgesia, or improve the quality of analgesia.     

产程中应用杜冷丁对产程及新生儿的影响

目的　观察杜冷丁对产程及新生儿的影响。方法　将 16 0例初产妇随机分为观察组和对照组 ,各 80例 ,观察组在宫口开大 1.2cm时杜冷丁 10 0mg肌肉注射 ,对照组未用药。结果　第一产程用药组与对照组相比明显缩短 ,有显著差异 (P <0 .0 5 ) ,第二、三产程无差异 (P >0 .0 5 ) ,对新生儿影响、产后 2小时内出血量及新生儿体重两组无差异 (P >0 .0 5 )。结论　产程中应用杜冷丁可减轻产妇疼痛 ,缩短第一产程 ,不增加新生儿窒息 ,值得推广应用     

Comparison between pentazocine, pethidine and placebo in the treatment of post-anesthetic shivering

BACKGROUND: We have compared the effects of pethidine, pentazocine and placebo in the treatment of post-anesthetic shivering. METHODS: Forty-five patients who shivered after routine surgery were allocated randomly to receive normal saline (n=15), pentazocine 7.5 mg (n=15) or pethidine 17.5 mg (n=15). RESULTS: After 10 min, 13 patients had stopped shivering in the pethidine group, which was significantly more than the incidence in the two other groups (placebo=2; pentazocine=4) (P<0.01). Pentazocine was not significantly different from normal saline in affecting shivering. CONCLUSION: We conclude that pentazocine 7.5 mg was not effective in the treatment of post-anesthetic shivering.     

A comparison of a new analgesic,nefopam hydrochloride,with morphine sulphate,pentazocine and pethidine hydrochloride in post-operative pain

Summary

The analgesic potency of nefopam was compared to that of morphine, pentazocine and pethidine, double-blind in 200 patients with post-operative pain. Each drug was given as a single intramuscular injecton on the first post-operative day. Pain relief was measured both with a 0 to 3 graded pain scale and a 0 to 10 visual analogue scale and expressed as pain intensity, pain intensity difference and sum of pain intensity difference. The degree and time course of pain relief was similar for all four treatments with maximum analgesia 90 minutes after injection. Side-effects were reported by 58% of patients on nefopam compared to 68% on morphine, 82% on pentazocine and 74% on pethidine, the commonest side-effect being sleepiness. These results suggest that nefopam is a sufficiently potent analgesic agent to control post-operative pain, with a relatively low incidence of side-effects.     

Non-neuraxial analgesia in labour

Pain in labour is often described as one of the most severe pains experienced. Neuraxial techniques provide the most effective form of labour analgesia. However, not all women wish to have this or indeed want complete pain relief in labour. There are also subgroups of women in whom neuraxial techniques are contraindicated or attempted placement is unsuccessful. Therefore delivery units must be able to offer a range of non-neuraxial analgesia options for labour.     

Preparation and Functional Identification of a Novel Conotoxin QcMNCL-XIII0.1 from Conus quercinus

Conotoxins are tools used by marine Conus snails to hunt and are a significant repository for marine drug research. Conotoxins highly selectively coordinate different subtypes of various ion channels, and a few have been used in pain management. Although more than 8000 conotoxin genes have been found, the biological activity and function of most have not yet been examined. In this report, we selected the toxin gene QcMNCL-XIII0.1 from our previous investigation and studied it in vitro. First, we successfully prepared active recombinant QcMNCL-XIII0.1 using a TrxA (Thioredoxin A)-assisted folding expression vector based on genetic engineering technology. Animal experiments showed that the recombinant QcMNCL-XIII0.1 exhibited nerve conduction inhibition similar to that of pethidine hydrochloride. With flow cytometry combined fluorescent probe Fluo-4 AM, we found that 10 ng/μL recombinant QcMNCL-XIII0.1 inhibited the fluorescence intensity by 31.07% in the 293T cell model transfected with Cav3.1, implying an interaction between α1G T-type calcium channel protein and recombinant QcMNCL-XIII0.1. This toxin could be an important drug in biomedical research and medicine for pain control.     

Opiate-sensitivity: clinical characteristics and the role of skin prick testing

BACKGROUND: The value of skin prick testing in opiate-sensitive individuals is uncertain as opiates cause non-specific weals by direct degranulation of mast cells. OBJECTIVE: To define whether skin prick test (SPT) responses to opiates in opiate-sensitive individuals are different to those seen in the normal population and to describe the clinical characteristics of this group of subjects. METHODS: The SPT responses of eight opiate-sensitive subjects to morphine 10 mg/mL, pethidine (meperidine) 50 mg/mL and papaveretum 15.4 mg/mL at four different concentrations (undiluted, 1/10, 1/50 and 1/100) were compared with the responses of 100 (32 atopic) non-opiate-sensitive control subjects. Four of the opiate-sensitive subjects had a clinical history of asthma, rhinitis or urticaria on occupational exposure to morphine. One subject developed urticaria with codeine, one developed urticaria and asthma with morphine and diamorphine and two subjects reacted to intravenous papaveretum with anaphylaxis or urticaria. Five out of the eight cases had opiate sensitivity confirmed by single-blind placebo-controlled oral challenge. RESULTS: Skin prick tests to all three opiates were not significantly different when the eight opiate-sensitive subjects were compared with either the entire normal control group or the subgroup of 47 definite opiate-tolerant controls that had previously received opiates for clinical indications. Furthermore, there were no significant differences in size of opiate SPT responses between atopic and non-atopic control subjects. In the control subjects, there was a positive correlation in SPT weal size between the three opiates. CONCLUSION: Skin prick testing is not useful in the diagnosis of opiate sensitivity and placebo-controlled challenge should be considered.     

野木瓜用于术后镇痛的疗效

目的 :观察野木瓜用于术后镇痛疗效。方法 :将 5 8例腹部、下肢择期手术病人分为 2组 ,野木瓜组 30例用野木瓜 0 .16 6 g·kg- 1,哌替啶组 2 8例用哌替啶 0 .8mg·kg- 1,均在术后疼痛时肌内注射 ,共 2次。结果 :野木瓜组优良 2 4例 (80 % ) ,有效 5例 (16 % ) ,无效 1例 (4% ) ,总有效率 96 % ,哌替啶组优良 2 3例 (82 % ) ,有效 4例 (14% ) ,无效 1例(4% ) ,总有效率 96 %。 2组总有效率经 χ2 检验 ,差异无显著意义 (P >0 .0 5 )。野木瓜组镇痛时间6 .2h±s1.4h ,哌替啶组 3.5h± 1.2h ,经t检验差异有显著意义 (P <0 .0 5 )。结论 :野木瓜术后镇痛效果确定 ,镇痛维持时间长     

Analysis of pethidine disposition in the pregnant rat by means of a physiological flow model

The disposition of pethidine (meperidine) in the pregnant rat is described by means of a physiological flow model. The model includes arterial and venous blood, brain, fat, fetal, hepatic, intestinal, muscular, pulmonar, and renal tissues. The concentration-time profiles of pethidine calculated by the model are consistent with experimental data, except for the brain and renal tissues, where the model predicts initially higher concentrations. Simulations are carried out to further explore the contribution from different organs on the kinetics in blood and tissues. The tissue-to-blood partition coefficients vary over a range from 5 to 316, where fat has the lowest and liver the highest after a correction is made due to hepatic extraction. Rapid uptake occurs into highly perfused organs such as brain, kidneys, liver, and lungs, followed by fetus, intestines, muscle, and fat. Data indicate no marked membrane resistance to pethidine of the investigated organs, except for fetal tissues, but rather a perfusion-limited uptake. Simulations suggest that muscles and adipose tissue play an important role in the rat, becoming the major reservoir of drug during the intermediate and terminal elimination phase, respectively. Volume of distribution and the biological half-life agree with reported findings. Pethidine is subject to a high systemic blood clearance, which exceeds the total hepatic blood flow in the rat. No degradation of pethidine is found in blood, and therefore a pulmonary expression for pethidine clearance is added as a potential source of pethidine elimination. The elimination of pethidine after a single i.v. bolus dose is found to be dependent on simulated changes in cardiac output and hepatic blood flow. A simulation is performed with the scaled model to mimic the human concentration-time profiles in maternal blood and brain tissues and fetal tissue during repetitive doses of pethidine.     

Analgesic and respiratory effect of nalbuphine and pethidine for adenotonsillectomy in children with obstructive sleep disorder

Opioids may depress respiration and contribute to airway obstruction after adenotonsillectomy for obstructive sleep disorder. We compared the respiratory and analgesic effects of nalbuphine, which has a ceiling effect for respiratory depression, and pethidine in 90 children (aged 2–12 years) with a history of obstructive sleep disorder undergoing adenotonsillectomy. Children were scored for their obstructive sleep disorder history and were randomly allocated to receive intravenously at induction of anaesthesia either nalbuphine 0.1 mg.kg⁻¹ (group N) or pethidine 1 mg.kg⁻¹ (group P). End-tidal carbon dioxide was measured in the recovery period using a nasopharyngeal catheter and oxygen saturation whilst breathing air; pain and sedation scores were recorded for 6 h postoperatively. Both groups were similar with respect to the demographic data and respiratory measurements: mean (SD) oxygen saturation on air in the recovery area (96.2% (1.2) vs. 96.5% (1.1) in group N and P, respectively) and mean (SD) end-tidal carbon dioxide (46.4 (5.5) mmHg vs. 47.7 (4) mmHg in group N and P, respectively). High obstructive sleep disorder score, history of apnoea, hyperactivity and loud snoring were found to be the best predictors of early postoperative oxygen desaturation in both groups.