Intravenous phentolamine infusion alleviates the pain of abdominal visceral cancer,including pancreatic carcinoma

This case report series describes eight patients (four patients with pancreatic carcinoma, one patient with hepatocellular carcinoma, one patient with gastric and rectal carcinoma, one with sigmoid colon cancer, and one with rectal cancer), whose abdominal cancer pain was treated with intravenous phentolamine infusion at 80 mg·day⁻¹ for 2 days. All but one of the patients had already been treated with opioids. All eight patients complained of severe abdominal pain; in five patients the pain radiated to the back, and there was associated anal pain in two patients. Analgesia was achieved in three patients; pain alleviation was obtained in four patients, but was not sustained in two of these four patients; and the treatment in one patient could not be judged for efficacy because epidural morphine was used together with the phentolamine. Adverse effects of phentolamine were tachycardia and/or hypotension.     

Peripheral nerve blocks for cancer pain

Pain is a common symptom in patients with advanced cancer, but in the majority of patients the pain is well controlled with conservative management techniques. In a small proportion of patients (5–10%) more invasive analgesia regimens are required, including the use of peripheral nerve blocks, where pain arises within the territory of a major peripheral nerve or plexus. These blocks may be single-shot injections of long-acting local anaesthetic performed using standard approaches to the nerve. More commonly, perineural or plexus infusions are employed using special nerve sheath catheters through which infusions of local anaesthetic drugs are administered for weeks or even months, according to the severity of the pain and the patient's life expectancy. Placing the catheters and controlling the infusion can be technically demanding and the catheters require careful attention to detail to avoid infection, blockage or accidental removal throughout the duration of the infusion.Despite the difficulties of inserting and maintaining a successful peripheral nerve catheter infusion, the quality of analgesia available from such techniques can result in a major improvement in the quality of life for the patient. These techniques should be considered at an early stage in patients where pain management within the territory of an appropriate nerve or plexus is difficult.     

慢性内脏痛及其信号转导通路的研究进展

背景 慢性内脏痛是功能性胃肠病(functional gastrointestinal disorders,FGID)和慢性胰腺炎(chronic pancreatitis,CP)的主要症状,这种疼痛不但降低患者的生活质量也是其寻求医疗帮助的主要原因,但目前有关内脏痛的确切机制仍不清楚,因而其治疗效果不佳. 目的 就当前慢性内脏痛及其信号转导通路的研究进展进行综述. 内容 介绍内脏痛及其信号转导通路、神经胶质细胞特别是脊髓小胶质细胞在慢性内脏痛中的作用. 趋向 脊髓小胶质细胞可能是未来慢性内脏痛治疗的新靶点.     

Ultrasound-guided pain interventions in the pelvis and the sacral spine

Ultrasound guidance of infiltrations in the management of chronic pain allows us to visualize in “real time” the advance of the needle and the diffusion of the analgesic agent in and around the pain-generating anatomical structures. It also enables us to avoid important structures, blood vessels, for example, located in the path of the puncture, thus, avoiding complications. The pelvic area has many pain-generating zones, including joints, muscles, and certain specific points, where nerve structures can be compressed. The involvement of these structures can produce pelvic or lower back pain along with pain that radiates to the lower limbs. Owing to its inability to penetrate bone, ultrasound is unable to visualize, and therefore infiltrate, a number of important nerves located on the anterior face of the sacrum, including the ganglion impar, inferior hypogastric plexus, and superior hypogastric plexus. In this article, we describe different techniques for the ultrasound-guided infiltration in the pelvic region, including the sacroiliac joint, pudendal nerve, coccygeal nerves, transsacral block, lateral branches of the posterior sacral roots, dorsal branch of the L5, caudal epidural infiltration, infiltration of the piriformis and gluteus medius muscles, infiltration of the iliolumbar ligament, ganglion impar block, and superior hypogastric plexus block.     

Tramadol for pain relief in children undergoing herniotomy: a comparison with ilioinguinal and iliohypogastric blocks

BACKGROUND: Prevention of postoperative pain in children is one of the most important objectives of the anesthesiologist. Preoperative ilioinguinal and iliohypogastric nerve blocks have been widely used to provide analgesia in children undergoing herniorrhaphy. Tramadol is an analgesic with micro-opioid and nonopioid activity. In this study we compared the usage of intravenous tramadol with ilioinguinal and iliohypogastric nerve blocks for control of post-herniorrhaphy pain in children aged 2-7 years. METHODS: Sixty patients were randomly allocated to two groups of thirty. One group received tramadol 1.5 mg.kg(-1) i.v. before induction of general anesthesia and the other had an ilioinguinal and iliohypogastric nerve block with 0.5% bupivacaine (0.25 ml.kg(-1)) before skin incision. We assessed pain using the Children's Hospital of Eastern Ontario Pain Scale and the Categorical Pain Scale. RESULTS: At 1, 4 and 24 h after surgery the two groups had identical pain scores. At 2 and 3 h after surgery the tramadol group experienced significantly less pain (P < 0.05). The rescue drug for residual pain, was used equally in the two groups. None of the 60 patients had respiratory depression but the tramadol group patients were found to have more episodes of nausea and vomiting (P < 0.05). CONCLUSIONS: We concluded that tramadol can have at least the same analgesic effect as that of ilioinguinal and iliohypogastric nerve blocks for post-herniorrhaphy pain in children, with even a superior effect at the time of maximal analgesia. We also highlight the troublesome side-effect of nausea and vomiting which brings into question the benefits of using this opioid that seems to lack respiratory depression.     

Ultrasound-guided serial ilioinguinal nerve blocks for management of chronic groin pain secondary to ilioinguinal neuralgia in adolescents

We examined the efficacy of serial ilioinguinal nerve blocks using ultrasound guidance for management of chronic inguinal pain secondary to persistent ilioinguinal neuralgia in adolescents. This case series consists of two adolescents who had persistent inguinal pain secondary to ilioinguinal neuralgia who were treated with conventional pain medications that did not relieve the pain. One patient had pain immediately following surgery while the other had pain several months after an injury. Serial ilioinguinal nerve blocks were performed with local anesthetic solution using ultrasound guidance in an outpatient setting. Both the adolescents had complete relief of pain symptoms and were able to resume normal activities. There were no adverse effects associated with the blocks. Performance of serial ilioinguinal nerve blocks using ultrasonography in an outpatient setting in adolescents and adolescents with ilioinguinal neuralgia may reduce pain and allow these adolescents to resume their normal activities.     

Cyclophosphamide-induced cystitis in freely-moving conscious rats: behavioral approach to a new model of visceral pain

PURPOSE: To develop a model of visceral pain in rats using a behavioral approach. Cyclophosphamide (CP), an antitumoral agent known to produce toxic effects on the bladder wall through its main toxic metabolite acrolein, was used to induce cystitis. MATERIALS AND METHODS: CP was administered at doses of 50, 100 and 200 mg./kg. i.p. to male rats, and their behavior observed and scored. The effects of morphine (0.5 to 4 mg./kg. i.v.) on CP-induced behavioral modifications were tested administered alone and after naloxone (1 mg./kg. s.c.). In addition, 90 minutes after CP injection, that is, at the time of administration of morphine, the bladder was removed in some rats for histological examination. Finally, to show that the bladder is essential for the CP-induced behavioral modifications, female rats also received CP at doses of 200 mg./kg. i.p. and of 20 mg. by the intravesical route, and acrolein at doses of 0.5 mg. by the intravesical route and of 5 mg./kg. i.v. RESULTS: CP dose-relatedly induced marked behavioral modifications in male rats: breathing rate decrease, closing of the eyes and occurrence of specific postures. Morphine dose-dependently reversed these behavioral disorders. A dose of 0.5 mg./kg. produced a reduction of almost 50% of the behavioral score induced by CP 200 mg./kg. This effect was completely prevented by pretreatment with naloxone. At the time of administration of morphine, histological modifications of the bladder wall, such as chorionic and muscle layer edema, were observed. In female rats, CP 200 mg./kg. i.p. produced the same marked behavioral modifications as those observed in male rats. Administered at the dose of 20 mg. intravesically, CP did not produce any behavioral effects, whereas acrolein at 0.5 mg. intravesically induced behavioral modifications identical to those under CP 200 mg./kg. i.p., with the same maximal levels. Conversely, acrolein 5 mg./kg. i.v. did not produce any behavioral effects at all. CONCLUSIONS: Overall, these results indicate that this experimental model of CP-induced cystitis may be an interesting new behavioral model of inflammatory visceral pain, allowing a better understanding of these painful syndromes and thus a better therapeutic approach to them.     

Inferior alveolar nerve blocks for postoperative pain control after mandibular distraction with osteotomies in a neonate

We describe the use of inferior alveolar nerve blocks (IANBs) for postoperative pain control for a neonate undergoing mandibular distraction and osteotomies. In this case, bilateral IANBs were effective in keeping low pain scores as assessed on the neonatal infant pain scale (NIPS) and the amount of opioid and adjuvant analgesics used. The blocks were assessed to have lasted approximately 24 h making serial blocks for pain control logistically feasible. Additionally, pain control was improved throughout the period of distractor advancement (approximately 7 days). We propose the routine use of this regional technique for improved pain control after this procedure in neonates and suggest that improved pain control may facilitate earlier extubation in this challenging population.     

Laser Doppler perfusion imager (LDPI) - for the assessment of skin blood flow changes following sympathetic blocks

A laser Doppler perfusion imager (LDPI) for evaluation of skin blood flow is presented and its use illustrated in two cases with a presumptive diagnosis of reflex sympathetic dystrophy (RSD) treated with local anesthetic sympathetic blocks. Among the advantages are the good spatial resolution over the area measured (12 times 12 cm) and that measurements can be done without contact with the skin. Generating a complete image takes 4.5 min but if higher temporal resolution is needed continuous measurements at one point are possible by use of another software routine.     

A comparison of intraoperative celiac plexus block with pharmacological therapy as a treatment for pain of unresectable pancreatic cancer

Background/Purpose: The efficacy of intraoperative celiac plexus block was compared with that of pharmacological therapy in the treatment of pain caused by unresectable pancreatic cancer. Methods: Twenty-one patients were included in the study: 15 patients underwent intraoperative celiac plexus block (group 1) and 6 received pharmacological therapy (group 2). The effectiveness at 1 week after treatment and from treatment to death was evaluated at follow-up by looking at mean analgesic consumption, mortality and morbidity, and any postoperative complications. Statistical analysis was performed using unpaired t-tests. Results: One week after the operation, the analgesic consumption of 14 patients in group 1 was the same as that before treatment, and 1 patient's consumption had decreased. Pain in 4 patients in group 2 did not change, but in 2 patients it increased. Mean opioid consumption was significantly lower in group 1. Complications related to the block were transient diarrhea and hypotension (P not significant between groups). There was no operative mortality or major complication related to the block. The incidence of adverse drug-related effects, such as constipation, nausea, and vomiting, was significantly lower in group 1 than in group 2. Conclusions: Intraoperative celiac plexus block made pain control possible with reduced opioid consumption, representing an effective, safe, and simple tool for the treatment of pain caused by unresectable pancreatic cancer. Received: November 16, 2001 / accepted: February 28, 2002     

脊髓电刺激术治疗内脏痛的研究进展

背景 脊髓电刺激术(spinal cord stimulation,SCS)可以缓解多种原因导致的疼痛,改善器官功能,尤其对于神经病理性疼痛和周围血管病变引起的缺血性疼痛的治疗作用明显.最近研究发现,其对内脏痛性疾病也有艮好的缓解作用.目的 通过综述SCS在内脏痛中的应用及其作用机制,为内脏痛的治疗提供参考. 内容 SCS的发展及其对内脏痛的镇痛机制,对各种内脏痛相关疾病的治疗效应和进展. 趋向 SCS可以治疗药物治疗效果欠佳的内脏痛疾病,为内脏痛的治疗提供新的工具.     

Propofol: clinical strategies for preventing the pain of injection

Eight modes of administration of propofol were assessed in order to minimise the pain of injection. An intravenous bolus injection in the antecubital fossa was the only approach that caused no pain. When administered intravenously in the dorsum of the hand the pain score and the number of patients who experienced pain was reduced significantly by mixing the agent with lignocaine when compared with a bolus injection. Slowing the speed of injection caused the greatest discomfort. An indirect biochemical mechanism for the pain is proposed.     

Complications in lumbar fusion surgery for chronic low back pain: comparison of three surgical techniques used in a prospective randomized study. A report from the Swedish Lumbar Spine Study Group

The reported complication rates after various surgical techniques used to create a lumbar fusion vary within wide ranges. In a previous paper, the Swedish Lumbar Spine Study Group have reported on the clinical outcome of lumbar spine fusion for chronic low back pain in a comparably homogeneous patient population where there were no significant differences between baseline sociodemographic, clinical and paraclinical characteristics. In this report we compared the complication rates of the surgical procedures used in that study and analyzed the association between complications and baseline variables, and between outcome results and complications. A multicenter randomized study was conducted where 211 patients aged 25-65 were treated with lumbar fusion according to three different surgical techniques: noninstrumented posterolateral fusion (PLF, n=71), instrumented posterolateral fusion (VSP, n=68), and in the third procedure we added an interbody fusion with solid autogenous bone grafts ("360", n=72). We categorized complications as: early/late, major/minor. The association between complications and sociodemographic characteristics (age, gender, comorbidity, previous surgery, smoking), and technical variables (surgical technique, levels fused, hospital category) was analyzed. The association between outcome variables (patient global assessment, pain, disability, depressive symptoms) and complications was analyzed. A literature review was conducted. There was no mortality. There was no significant difference in clinical outcome between the surgical groups after 2 years, although the power to detect such a difference was low. The total complication rate after 2 years in the PLF group was 12%, compared with 22% in the VSP group, and 40% in the "360" group (P=0.0003). After exclusion of complications, there was still no difference in outcome between the groups. The odds ratio (confidence intervals) of having a complication was 5.3 (2.2-12.7) when "360" was used compared with PLF, and 2.4 (1.1-5.3) for "360" compared with VSP. There was no association between clinical outcome and complications on a group level. The reintervention rate was 6% in the PLF group, 22% in the VSP, and 17% in the "360" group (P=0.020). The odds ratio (confidence intervals) of having a reintervention was 4.0 (1.3-11.9) when instrumentation was used compared with non-instrumented fusion. In this prospective randomized study comparing three lumbar fusion techniques in a comparably homogeneous patient population, complications increased significantly with increasing technicality of the surgical procedure. Even though we did not find a significant association between clinical outcome and complications after 2 years, the increased morbidity inflicted on an individual patient was not negligible. In this light, and as no fusion technique produced superior clinical outcome irrespective of whether complications were included or excluded in the analyses, the patient and the treating physician should carefully discuss the possible advantages and drawbacks of the different surgical options before making a decision. In order to make valid comparisons of both complication and reintervention rates after lumbar fusion, there is a need for a consensus in the spinal society regarding the definition of these entities.