Monitoring of skin conductance in anesthesiology and intensive care

The purpose of the study is to examine the efficacy and safety through the introduction of a local anesthetic wound irrigation catheter for continuous postoperative analgesia in newborns. The study was conducted during the postoperative period of 33 full-term newborns. In the study group (n = 15), analgesia was carried out through the wound catheter with infusion of local anesthetic, for the control group (n = 18) continuous intravenous infusion promedol was used. The effectiveness of postoperative analgesia was rated by CRIES postoperative pain control scale, monitoring of skin conductance, cardiointervalogram and hormone level control in the blood. The study showed that the use of wound catheter for continuous postoperative analgesia with local anesthetics provides effective level of analgesia in newborns, which is comparable with the introduction of opioid analgesics. There were no severe postoperative complications. The method of analgesia by administering a local anesthetic through the wound catheter can be recommended for postoperative analgesia in newborns, especially during major surgeries.     

Local anesthetics as adjuvant analgesics

Local anesthetics administered to block nerve conduction for surgical anesthesia and to provide analgesia in management of acute pain have become a standard of anesthesiology practice. These drugs have had an important role in the multimodality management of chronic pain as well, and this role is expanding since the revival of systemic administration. Local anesthetics are analgesics, albeit not in the traditional clinical and pharmacologic sense. Evidence suggests that intravenous administration is an effective treatment in chronic neuropathic pain syndromes. There is also evidence that intravenous local anesthetics can relieve acute pain. Furthermore, the novel idea that acute procedural and postprocedural pain control with local anesthetics could prevent the development of chronic pain syndromes, including chronic neuropathic pain syndromes, adds another important potential dimension to the role of local anesthetics in pain management.     

地佐辛超前镇痛用于锁骨下臂丛神经阻滞的效果评价

目的:观察地佐辛超前镇痛用于臂丛神经阻滞的效果及对术后疼痛的影响。方法:将美国麻醉医师协会(ASA)分级Ⅰ~Ⅱ级、行锁骨下臂丛神经阻滞的60例手术患者随机分为3组,每组20例。A组将地佐辛5 mg与局部麻醉药(0.375%罗哌卡因20 mL+1%利多卡因15 mL+1∶20万肾上腺素1 mL)混合用于臂丛神经阻滞。B组于术前15 min静脉注射地佐辛5 mg,联合局部麻醉药(同A组);C组仅行锁骨下臂丛神经阻滞,局部麻醉药同A组。记录麻醉起效时间,手术时间,麻醉后1 h及术后4、8、12、24、36、48 h的疼痛视觉模拟评分(VAS),术后镇痛持续时间(术毕至术后VAS3分的时间),不良反应。结果:A组麻醉起效时间低于B、C组(P0.05)。A、B组术后8 h时的VAS明显低于C组(P0.05);A组术后12、24 h时的VAS明显低于B、C组(P0.05);3组麻醉后1 h及术后4、36、48 h时的VAS差异无统计学意义(P0.05)。术后镇痛持续时间为A组B组C组,差异有统计学意义(P0.05);A组和B组不良反应发生率差异无统计学意义(P0.05)。结论:地佐辛超前镇痛效果确切,能够延长术后镇痛时间,且不良反应少。     

Präemptive Analgesie: Klinische Realität oder wissenschaftliche Hypothese?

Numerous experimental studies have shown that systemic or regional administration of analgesics prior to a nociceptive stimulus results in a significant reduction of analgesic requirements compared with the administration of the same analgesic dose given after the nociceptive stimulus. This phenomenon is called "preemptive analgesia". Recently several clinical studies have been conducted to determine whether "preemptive analgesia" also occurs in humans. Regional and systemic opioids, local anesthetics and non-steroidal anti-inflammatory drugs have been investigated so far. Most studies have failed to show a significant reduction in postoperative analgesic requirements with preemptive analgesia. Even in studies with positive results the reduction in analgesic requirements was limited and without clinical relevance. Further studies should focus on the questions which analgesics and which administration routes might provide clinically significant "preemptive analgesia" and how long analgesia should be prolonged into the postoperative period.     

Preemptive analgesia: Moving beyond conventional strategies and confusing terminology

Trials of preemptive analgesia compare the effect of drugs administered before injury with the same treatment administered after injury, whereas studies of perioperative analgesia include comparisons of preinjury administration with no particular analgesic treatment at all. In contrast to earlier reports, recent animal behavioral studies of persistent nociception and clinical trials of preemptive analgesia using randomized, controlled protocols strongly indicate that conventional treatments such as local anesthetics and opioids do not exhibit significant preemptive analgesic effects for postoperative pain. The direction of perioperative medicine must be shifted away from conventional preemptive analgesia studies, and towards (1) preemptive analgesia studies using novel treatment strategies; (2) perioperative analgesic strategies involving continuous administration of analgesics and anesthetics; and (3) a focus on clinical outcomes involving hospital stay, cost, and patient satisfaction.     

Caudal anesthesia and its determinant factors

In 130 surgical patients with diseases and injuries in the area of the perineum and lower extremities the clinical effects of three modern local anesthetics: 2% solution of lidocaine, 0.5% solution of bupivacaine, 0.75% solution of ropivacaine and their combinations (2% lidocaine and 0.25% bupivacaine solution 2% lidocaine and ropivacaine 0.375% solution) were followed with regard to the influence of increasing volumes of local anesthetics and different rates of drug administration. It is established that an effective caudal anesthesia is provided with all modern local anesthetics, with increasing use of local anesthetic solution to 40 ml provides duration and the prevalence of sensory and motor blocks, the use of mixture of local anesthetics optimizes the development and maintenance of the caudal blockade.     

Beeinflußt die Schmerztherapie postoperative Morbidität und Letalität?

Postoperative pain can intensify the sympathoadrenergic reaction, which is commonly seen after surgery, and thus possibly pave the way for certain complications, such as coronary ischemia, bronchopneumonia, intestinal stasis, thromboembolism, infection, sepsis, and metabolic disturbances. Investigations of cardiovascular, respiratory, gastrointestinal, metabolic, and immunologic function indicate that high-quality pain relief can diminish postoperative organ impairment and failure. Some aspects of the improvements attributed to the quality of analgesia, such as prevention of tachycardia and hypertension, attenuation of hyperglycemia and catabolism, improvement of gastrointestinal motility and cellular immunity cannot be definitely distinguished from the effects of sympathetic blockade due to epidural analgesia with local anesthetics, however. There is another aspect of the problem. The better the quality of postoperative pain relief, the more likely it is that analgesia-related complications, such as respiratory depression (opioids), cardiovascular depression (epidural local anesthetics), renal failure (NSAIDs) and bladder dysfunction (epidural opioids and local anesthetics) will occur. The question of whether postoperative morbidity and mortality can be reduced by effective analgesia has been investigated in the past few years. Some studies indicate that better analgesia is advantageous for the patient, especially with respect to postoperative complications, hospital stay, long-term well being, and costs. In other clinical trials incorporating more patients, however, this hypothesis had to be rejected. At present, therefore, we cannot state that effective pain relief influences postoperative morbidity and mortality.     

药物控释体系用于局部麻醉的研究进展

减少用药次数、延长术后镇痛时间是临床局部麻醉的重要需求。然而,无论是当前临床使用的局麻药,还是生物毒素类潜在新型麻醉药均存在时效较短的问题。利用脂质体、聚合物微球等药物载体装载局麻药进行控释,可实现药物的长效、按需释放,从而满足临床需求。本文简要概述可用于局麻药控释的药物载体,并介绍具有代表性的药物控释体系的设计、功能及其用于局部麻醉的最新研究进展,同时对此研究领域的挑战及未来前景进行讨论。     

Permanent Neurologic Symptoms after Prolonged Epidural Analgesia

Objective: Although transient neurologic symptoms may occur after neuraxial anesthetics with lidocaine, permanent neurologic symptoms (PNS) are unusual after uncomplicated continuous epidural analgesia (CEA). This report demonstrates that PNS may follow CEA uncomplicated by paresthesias, dural puncture, spinal hemorrhage, or intravascular local anesthetic injection; and performed with bupivacaine alone administered at high dosages with vasoconstrictors over a prolonged time period. Case Report: An obstetrical patient developed fixed left L5‐S1 sensorimotor radiculopathy following L5‐S1 level CEA with bupivacaine alone administered at high doses (270 mg) with a vasoconstrictor (epinephrine, 225 mg) over a prolonged time period (62 hours). Conclusions: CEA should be administered at higher lumbar levels for labor analgesia rather than at lumbosacral levels that may require higher volumes and concentrations of local anesthetics with greater potential for local anesthetic neurotoxicity. Local anesthetics with vasoconstrictors should only be used as sentinel markers of unrecognized intravascular entry, rather than as primary local anesthetics during CEA to avoid any potential for ischemic neuropathy.     

Synthesis and biological activities of local anesthetics

Local anesthetics are mainly used in stomatology, ophthalmology, gynecology and surgery to temporarily relieve pain. Local anesthetics act on nerve endings or around nerve trunks, and are combined with specific sodium ion (Na⁺) channel sites on the nerve membrane. They can affect the membrane potential by reducing Na⁺ passage through sodium ion channels, thus blocking the generation and conduction of nerve impulses, reversibly blocking the generation and conduction of sensory nerve impulses. Local anesthetics are used for convenience in local surgical operations and treatments. Herein, we mainly review the research progress on local anesthetics and discuss the important aspects of design, synthesis and biological activity of various new compounds.

Local anesthetics are mainly used in stomatology, ophthalmology, gynecology and surgery to temporarily relieve pain.     

Pharmacological and physiological specificities of local anesthesia in dentistry

Described in the paper are the specificity of local analgesia at the medical dental procedures and the effect produced by local anesthetics and vasoconstrictive agents on the induction of nervous fibers and peripheral blood circulation. The pharmacological-and-physiological mechanisms of local analgesia by a 2% artikain solution (with adrenalin, concentration 1:100,000) and by a 2% mepivakain solution (with adrenalin, concentration 1:100,000) exerted on the pain sensitivity and blood circulation in the tooth pulp are analyzed.     

Nicotinic acetylcholine receptors mediate the hypnotic and analgesic effects of emulsified inhalation anesthetics

This study was designed to investigate the role of nicotinic acetylcholine receptors (nAChRs) in hypnosis and analgesia induced by emulsified inhalation anesthetics. After having established the mice model of hypnosis and analgesia by intraperitoneal injections of appropriate doses of enflurane, isoflurane or sevoflurane, we intracerebroventricularly or intrathecally injected different doses of nicotine and then observed the effects on the sleeping time using awaken test and the pain threshold in hot-plate test (HPPT) using hot-plate test. In the awaken test, 10, 20 and 40 μg of nicotine (intracerebroventricularly) significantly decreased the sleeping time of the mice treated with the three emulsified inhalation anesthetics mentioned above ( P  <   0.05 or 0.01). In the HPPT, 5, 10 and 15 μg of nicotine (intrathecally) did not affect the HPPT in conscious mice ( P  >   0.05); in contrast, 5, 10 and 15 μg of nicotine (intrathecally) significantly decreased the HPPT of the mice treated with emulsified inhalation anesthetics ( P  <   0.05 or 0.01). The data presented in this study suggest that nAChRs may be important targets for the hypnotic and analgesic effects induced by emulsified enflurane, isoflurane and sevoflurane.     

Tissue toxicity of local anesthetics. An in vivo trial

AIM: Local anesthetics are often administered intra-articularly after knee surgery. The aim of this study was to determine differences in irritancy of local anesthetics in an in vivo test performed on the chorioallantoic membrane of hen's eggs (HET-CAM test) to evaluate the specific irritation score. METHOD: After incubation for 9 days, the chorioallantoic membrane was prepared and then exposed to different local anesthetics (Naropin, Scandicain,Carbostesin,Xyloneural). RESULTS: We found no irritating values for the tested substances. No vascular injuries of the chorioallantoic membrane could be detected. Therefore, the irritation score was measured according to the standard protocol with an irritation score=0. CONCLUSION: Our results show that local anesthetics often used in clinics do not provoke severe vascular injuries as a sign of tissue toxicity. Therefore, the customary concentrations can be recommended for clinical use.     

Intrapleural anesthesia following thoracic surgery and in chest trauma

The analgesic effect of intrapleural administration of local anesthetics (lidocaine, trimecaine, azocaine) has been studied in 180 patients after thoracic surgery and with chest trauma. The effect was assessed on the basis of subjective (visual analogue 10-score scale) and objective findings (hemodynamic parameters, spirograms, ECG). In control patients analgesia was performed by intramuscular promedol administration. It has been shown that fractionated intrapleural administration of local anesthetics is an effective and safe analgesic technique after thoracic surgery and in chest trauma.     

Principles of office anesthesia: part II. Topical anesthesia

The development of topical anesthetics has provided the family physician with multiple options in anesthetizing open and intact skin. The combination of tetracaine, adrenaline (epinephrine), and cocaine, better known as TAC, was the first topical agent available for analgesia of lacerations to the face and scalp. Cocaine has been replaced with lidocaine in a newer formulation called LET (lidocaine, epinephrine, and tetracaine). For analgesia to nonintact skin, LET gel is generally preferred over TAC because of its superior safety record and cost-effectiveness. EMLA (eutectic mixture of local anesthetics) is perhaps the most well-known topical anesthetic for use on intact skin. EMLA can be used to anesthetize the skin before intramuscular injections, venipuncture, and simple skin procedures such as curettage or biopsy. To be fully effective, EMLA should be applied at least 90 minutes before the procedure. ELA-Max is a new, rapidly acting topical agent for intact skin that works by way of a liposomal delivery system and is available over the counter. Other delivery vehicles for topical anesthesia currently in development, including iontophoresis and anesthetic patches, may one day give patients and physicians even more flexibility.     

Characteristics of anesthesia in children operated on for extrahepatic portal hypertension

Portocaval shunting reliably preventing hemorrhages from esophagogastric veins is most often used in surgery for extrahepatic portal hypertension (EPH) in children. Difficulties of anesthesia for this intervention consists in essential alteration of volume bloodflow as a result of massive outflow of deposited blood to systemic circulation through the new bypass. This necessitates search for an adequate method of general anesthesia and variants of infusion therapy for surgical venous shunting in children with EPH. Sixty-eight children aged 1-15 years with the EPH syndrome were subjected to elective surgery under general analgesia (multicomponent balanced neuroanesthesia with evaluation of some hemodynamic and metabolic parameters). The proposed protocol of general anesthesia in combination with epidural analgesia by local anesthetics and promedole and infusion therapy in the hypervolemic hemodilution mode create the most favorable conditions for adaptation of hemodynamics to increased preloand.     

双氯芬酸钠栓在会阴侧切缝合术中的研究

目的探讨双氯芬酸钠栓用于会阴侧切缝合术中及术后镇痛的疗效观察。方法随机将183例会阴侧切产妇分为观察组89例与对照组94例。两组用2％利多卡因会阴侧切局部麻醉,观察组在胎儿娩出结束第二产程及产后6h分别双氯芬酸钠栓直肠给药,观察会阴侧切缝合术中及产后会阴侧切伤口疼痛的镇痛效果、缝合时间、第三产程时间、产后出血量等。结果两组术中、术后镇痛效果、缝合时间比较,差异有统计学意义（P〈0．05或P〈0．01）;两组第三产程时间、产后出血量比较,差异无统计学意义（P〉0．05）。结论双氯芬酸钠栓用于会阴侧切缝合术中术后镇痛效果显著,并能缩短缝合时间,值得临床推广使用。     

Immunity and cytokine status after surgeries on the large intestine

The aim of our study was to examine the effect of individual schemes of multimodal analgesia on indicators of immunity and inflammation markers after operations on the colon. Patients of group 1 (n=15) received paracetamol, lornoxicam and epidural ropivacaine, 2nd group of patients (n=15)-paracetamol, epidural ropivacaine and tramadol. Comparison group (n=10) patients underwent patient controlled analgesia by promedol. Before surgery, 1st and 3rd days after surgery we examined the contents of cytokines in plasma: interleukin 12p70, interleukin 10, interleukin 6, and TNF. Before surgery and at 5-7 days after surgery indicators of cellular, fagocytal and humoral immunity were monitored. Before surgery patients with colorectal cancer revealed changes in the indices of different components of immunity, as well as an increase in pro-and anti-inflammatory cytokines compared with healthy donors. Multimodal analgesia in patients after operations on the colon is not accompanied by changes in plasma concentrations of cytokines and parameters of immune status in comparison with monoanalgesia by promedol.     

Systemic lidocaine silences ectopic neuroma and DRG discharge without blocking nerve conduction.

Systemic application of lidocaine in rats suppressed ectopic impulse discharge generated both at sites of experimental nerve injury and in axotomized dorsal root ganglion (DRG) cells. ED50 for DRGs was significantly lower than for the injury site. Lidocaine doses effective at blocking ectopic discharge failed to block the initiation or propagation of impulses by electrical stimulation, and only minimally affected normal sensory receptors. This selectivity may account for the effectiveness of systemic local anesthetics and other drugs that share the same mechanism of action (notably certain anticonvulsants and antiarrhythmics), in the management of neuropathic paresthesias and pain. In addition, it may account for the prolonged analgesia sometimes obtained using regional local anesthetic block.