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71.
目的观察鞘内注射舒芬太尼复合罗哌卡因在分娩镇痛中的效果。方法将156例ASAⅠ-Ⅱ级的健康初产妇随机分为观察组与对照组,每组各78例,观察组采用舒芬太尼复合罗哌卡因镇痛,对照组采用芬太尼复合罗哌卡因镇痛,双盲对照观察。所有产妇均采用蛛网下腔给药后硬膜外腔留管产妇自控镇痛,观察组硬膜外维持用药为0.2μg/ml舒芬太尼和0.1%罗哌卡因,对照组为2μg/ml芬太尼和0.1%罗哌卡因。观察比较两组给药后的镇痛起效时间、镇痛维持时间、镇痛满意度、各时间点的VAS评分、运动阻滞、产后出血量、产程、新生儿情况及不良反应发生情况。结果观察组的镇痛起效时间较对照组快,且镇痛效果、镇痛维持时间及镇痛满意度均明显优于对照组,两组相比较差异有统计学意义(p<0.05);观察组90 min以后的镇痛效果优于对照组,差异有显著性(p<0.05);两组的Bromage评分、产后出血量、产程、新生儿情况及不良反应发生率相比较差异无统计学差异(p>0.05)。结论舒芬太尼复合罗哌卡因鞘内给药在分娩镇痛中具有镇痛起效快、镇痛作用强、镇痛维持时间长、副作用少等优点,值得临床推广应用。  相似文献   
72.
BackgroundOur meta-analysis from 2013 showed that inserting a catheter intrathecally after an observed accidental dural puncture can reduce the need for epidural blood patch in labouring women requesting epidural analgesia. We updated our conventional meta-analysis and added a trial-sequential analysis (TSA).MethodsA systematic literature search was conducted to identify studies that compared inserting the catheter intrathecally with an epidural catheter re-site or with no intervention. The extracted data were pooled and the risk ratio (RR) and 95% confidence interval (95%CI) for the incidence of post-dural puncture headache (PDPH) was calculated, using the random effects model. A contour-enhanced funnel plot was constructed. A TSA was performed and the cumulative Z score, monitoring and futility boundaries were constructed.ResultsOur search identified 13 studies, reporting on 1653 patients, with a low risk of bias. The RR for the incidence of PDPH was 0.82 (95%CI 0.71 to 0.95) and the RR for the need for epidural blood patch was 0.62 (95%CI 0.49 to 0.79); heterogeneity of both analyses was high. The TSA showed that the monitoring or futility boundaries were not crossed, indicating insufficient data to exclude a type I error of statistical analysis. Contour-enhanced funnel plots were symmetric, suggesting no publication bias.ConclusionsConventional meta-analyses showed for the first time that intrathecal catheterisation can reduce the incidence of PDPH. However, TSA did not corroborate this finding. Despite increasing use in clinical practice there is no firm evidence on which to base a definite conclusion.  相似文献   
73.
Purpose In this randomized, double-blind study, we aimed to compare the effectiveness of lornoxicam and ondansetron for the prevention of intrathecal fentanyl-induced pruritus in patients undergoing cesarean section. Methods One hundred and eight parturients (American Society of Anesthesiologists [ASA] I-II status) requesting neuraxial analgesia by a combined spinal-epidural (CSE) technique were recruited for this study. A CSE technique was performed and anesthesia was achieved with fentanyl 25 μg and hyperbaric bupivacaine 12 mg. Patients were randomly allocated to three groups, each with 36 participants. Immediately following delivery, patients received either lornoxicam 8 mg IV (group L; n = 36), ondansetron 8 mg IV (group O; n = 36), or normal saline 2 ml IV (group P; n = 36). Pruritus, pain, and nausea and vomiting scores were recorded during the initial 24 h postoperatively. Results The incidence of pruritus was significantly lower in group O from 4 to 12 h postoperatively when compared to that in group L and group P. According to the pruritus grading system we used, the number of patients without pruritus was significantly higher in group O when compared to that in group L and group P. The number of patients experiencing moderate pruritus was significantly lower in group O when compared to that in group P. Conclusion We observed that the administration of 8 mg IV lornoxicam failed to prevent intrathecal fentanyl-induced pruritus in parturients. Also, our data confirmed that ondansetron is likely to attenuate intrathecal fentanyl-induced pruritus.  相似文献   
74.
BackgroundPostoperative nausea and/or vomiting affects up to 80% of parturients undergoing cesarean delivery, but there is a lack of obstetric-specific risk-prediction models. We performed this study to identify postoperative nausea/vomiting risk factors in parturients undergoing cesarean delivery, formulate an obstetric-specific prediction model (Duke score), and compare its performance against the Apfel score.MethodsA post-hoc analysis of data from two randomized controlled trials studying nausea/vomiting in women undergoing cesarean delivery with intrathecal morphine. Potential risk factors for postoperative nausea/vomiting within 24 h of surgery with univariate associations with P ≤0.20 were considered for inclusion in the multivariable analysis. After identifying the final multivariable model, we derived our Duke score by assigning points to the selected factors. We then tested the association of the Duke and Apfel scores with postoperative nausea and vomiting, and compared the area-under-the-receiver operating characteristic curve.ResultsAnalysis included 260 parturients, of whom 146 (56.2%) experienced postoperative nausea/vomiting. Non-smoking during pregnancy (OR 2.29 [95% CI 1.12 to 4.67], P=0.023), and history of postoperative nausea/vomiting after cesarean delivery and/or morning sickness (2.09 [1.12 to 3.91], P=0.021) were independent predictors of postoperative nausea/vomiting and included in the Duke score. Both Duke and Apfel scores trended linearly with postoperative nausea/vomiting risk (Duke P=0.001; Apfel P=0.049) and had comparable areas-under-the-receiver operating characteristic curve (Duke 0.63 [0.57 to 0.70]; Apfel 0.59 [0.52 to 0.65], P=0.155).ConclusionsBoth Duke and Apfel scores exhibited similar but poor predictive performance. Until better tools are developed, routine prophylactic anti-emetics appears to be a reasonable approach in this patient population.  相似文献   
75.
The purpose of this study was to evaluate haemodynamic stability, perioperative analgesia and neonatal outcome following intrathecal 0.5% bupivacaine 7.5 mg with varying doses of fentanyl, in parturients with pregnancy-induced hypertension. Forty-five parturients with pregnancy-induced hypertension scheduled for caesarean section were randomly allocated to receive 7.5 mg bupivacaine with saline 1 mL (group B), fentanyl 10 microg (group Bf10) or fentanyl 20 microg (group Bf20) intrathecally. Heart rate, blood pressure, and sensory block were recorded at regular intervals. Pain, nausea, vomiting, pruritus or any other side effects were sought. Neonatal outcome was assessed using Apgar score and umbilical artery blood gas analysis. Adequate surgical anaesthesia was established in all three groups. There was a statistically significant fall in mean arterial pressure in all three groups within 4-6 min of subarachnoid block (P<0.05), but the decrease in MAP was <20% of baseline in all three groups. Pain and discomfort during surgery were experienced more frequently in group B than in groups Bf10 and Bf20 (P<0.05). Duration of postoperative analgesia was significantly longer in group Bf20 (5.55+/-1.18 h) than in group Bf10 (3.97+/-2.12 h) and group B (3.27+/-1.8 h) (P<0.05). Neonatal outcome was similar in the three groups. Intrathecal fentanyl with low dose bupivacaine provides good surgical anaesthesia and prolongs the duration of analgesia without haemodynamic or neonatal compromise in patients with pregnancy-induced hypertension undergoing caesarean delivery.  相似文献   
76.
Intrathecal chemotherapy for hematologic malignancies: drugs and toxicities   总被引:1,自引:1,他引:0  
Intrathecal (IT) chemotherapy is an important component of the prophylaxis or treatment of hematologic malignancies in the central nervous system (CNS), especially in patients with acute lymphoblastic leukemia and aggressive lymphomas. Different regimens of IT chemotherapies have been formulated, often in conjunction with systemic high-dose chemotherapy leading to penetration of the drugs into the cerebrospinal fluid (CSF). The three commonest IT drugs are methotrexate, cytosine arabinoside (Ara-C), and corticosteroids. The CSF half-lives of methotrexate and Ara-C are much prolonged, a factor to be considered if these drugs are also administered systemically in high doses. Neurotoxicities attributed to IT chemotherapy have been reported, including spinal cord lesions, seizures, and encephalopathy. Spinal cord lesions, manifesting as tetraplegia, paraplegia, and cauda equina syndrome, are the commonest neurotoxicity. It is mostly related to combined IT methotrexate and Ara-C, or Ara-C as the sole IT agent when given at high doses or as a slow-release preparation. Cord lesions rarely recover and patients are left with motor deficits, bowel and urinary disabilities. Seizures and encephalopathy are reported in relatively fewer patients, with variable manifestations and prognosis. Knowledge of the pharmacokinetics, dosing schedules and potential toxicities of IT chemotherapeutic drugs is important in the design of CNS prophylaxis and treatment in hematologic malignancies.  相似文献   
77.
Systemic administration of remoxipride, a dopamine (D2) antagonist, to sheep has previously been shown to generate an antinociceptive action without producing a significant motor impairment. The present study examined whether a spinal locus of action was responsible for this action of remoxipride. Remoxipride (17.7 mg) administered intrathecally via chronically indwelling catheters produced a greatly variable but significant (p<0.05) increase in nociceptive thresholds as judged by a focused mechanical stimulus (blunt pin) applied to the forelimb of four sheep. However, this dose of remoxipride induced a marked forelimb motor impairment as judged by a subjective visual analogue scoring system. Conversely, intrathecal xylazine (100 and 200 μg), an α-adrenergic agonist with antinociceptive properties, did not produce forelimb weakness although the higher dose (200 μg) produced significant sedation. In vitro autoradiography was performed on cervical spinal cord sections taken from sheep. Remoxipride displaced [3H] YM-09151-2, a selective D2 antagonist, from densely-labelled areas in the superficial layer of the dorsal horn, lamina X and ventral horn. Even though there are possible anatomical substrates within the spinal cord for both an antinociceptive and motor disturbance action of remoxipride, the behavioural data suggest that the spinal cord is unlikely to be the primary site of antinociceptive action for systemically-administered doses of remoxipride. Received: 29 July 1996 / Accepted: 6 December 1996  相似文献   
78.
We have found that spinal NMDA receptors are involved in control of sympathetic output in pathways to the heart and vessels. The present study was done to determine whether spinal non-NMDA excitatory amino acid receptors participate in cardiovascular regulation. Experiments were done on urethane-anesthetized Sprague-Dawley rats, giving the non-NMDA receptor agonists, quisqualate and kainate, and the antagonist, kynurenate, intrathecally at the spinal T9 level. Both quisqualate (30 nmol; n = 7; to activate AMPA receptors) and kainate (2 nmol; n = 6; to activate K receptors) increased arterial pressure and heart rate. The responses were characterized by a rapid onset, achieving, in most cases, greater than 80% of the maximum response within 1-4 min, and a persistence throughout the remaining 20-24 min of the experiment. I.v. injection of hexamethonium (10 mg/kg) prevented the effects of intrathecal administration of quisqualate (n = 5) but not of kainate (n = 7). To determine whether the hexamethonium-resistant effects of kainate were due to a peripheral action, kainate was given i.v. (n = 6); it was found to be without effect on arterial pressure or heart rate. The increases in arterial pressure and heart rate produced by intrathecal administration of quisqualate (30 nmol; n = 6), kainate (2 nmol; n = 6), glutamate (1 mumol; n = 6) and NMDA (2 nmol; n = 6) but not carbachol (27.4 nmol; n = 6) were prevented by similar preadministration of kynurenate (125 nmol). Intrathecal administration of kynurenate (125 nmol; n = 6; 500 nmol; n = 7) decreased arterial pressure and/or heart rate.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
79.
The existence of a spinal network capable of generating rhythmic alternating activity resembling locomotion still has not been firmly established in primates, including man, although evidence for one is accumulating. The present study investigated whether it is possible to activate such a network by administration of a variety of pharmacological agents to acutely spinalized marmoset monkeys (Callithrix jacchus) in the absence of phasic afferent input to the spinal cord. Fourteen marmoset monkeys were decerebrated, spinalized, and paralyzed. The nerves supplying both hindlimbs were cut and recorded from. In 5 monkeys the effect of electrical stimulation of the brainstem was investigated before spinalization. In 3 of these monkeys, rhythmic activity alternating between extensors and flexor nerves was seen. In the 2 other monkeys only synchronized activity was elicited. In acutely spinalized monkeys, administration of l-3,4-dihydroxyphenylalanine (l-dopa; 3–4 h after treatment with nialamide) failed to evoke any rhythmic alternating activity. In contrast, administration of clonidine elicited alternating activity in all of 8 monkeys tested. In 4 of these monkeys, the activity was restricted to alternation between ipsilateral and contralateral flexor nerves, whereas alternating activity between ipsilateral flexors and extensors was also seen in the other 4 monkeys. Administration of excitatory amino acids (NMDA or NMA) also elicited rhythmic alternating activity in 7 of 10 spinalized monkeys. In 4, rhythmic alternating activity was seen between extensors and flexors on one limb as well as between ipsilateral and contralateral flexors. In 3 monkeys NMDA/NMA produced alternation between extensors and flexors of one limb without alternation between the ipsilateral and contralateral sides. Administration of noradrenaline failed to elicit any rhythmic activity, but rather completely depressed already existing activity. Administration of serotonin (5-HT) was ineffective in facilitating alternating activity in 6 of 8 monkeys and was facilitatory to rhythmic activity in the other 2. We suggest that these data provide further evidence of a network capable of eliciting rhythmic alternating activity resembling locomotion in the primate spinal cord. The network, however, seems to be more difficult to activate pharmacologically in those conditions than in other mammals. This may especially be the case in higher primates, including man. Received: 6 November 1997 / Accepted: 21 April 1998  相似文献   
80.
Introduction The baclofen pump has been utilized in children with refractory spasticity. However, in children with prior lumbar fusion, the implantation of such a device is difficult and fraught with complications. As an alternative to placing the pump catheter through the lumbar spine, we report our experience with placement of the catheter in the spinal canal via a cervical approach through the foramen magnum.Methods We have followed three patients with prior lumbar fusion and refractory spasticity, each of whom has undergone placement of the intrathecal component of a baclofen pump via the foramen magnum. Appropriate positioning of the catheter tip at the T6 spinal level was determined using intraoperative fluoroscopy. The catheter was then tunneled to the pump in the abdominal wall.Results All patients experienced a significant decrease in the severity of spasticity with pump placement. The pumps continued to function properly over a follow-up period of 24, 24, and 44 months respectively. In one patient, the catheter recoiled into the subcutaneous tissues several months after its placement, thus necessitating repositioning. One of the pumps was removed 2 years later secondary to a VP shunt infection. However, there were no immediate complications related to placement of the spinal catheter.Conclusions Placement of the intraspinal component of a baclofen pump via the foramen magnum is a viable alternative for patients with spastic quadriparesis with prior lumbar fusion. The tip of the spinal catheter can be positioned in the thoracic region in a similar manner to the placement traditional lumbar pumps. In our series, there were no adverse sequelae related to the surgery or catheter positioning.  相似文献   
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