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Purpose: The practice of regional anesthesia has been revitalized of late with the popularization of ultrasound-guided techniques. Advocates must be vigilant for the effects of unintentionally high blood levels of local anesthetic. Systemic local anesthetic toxicity, though rare, is a potentially devastating occurrence. This narrative review summarizes the effects of local anesthetic toxicity. We highlight how these toxic effects have motivated the search for a safe and long-acting local anesthetic. We outline current prevention and treatment options and appraise an emerging therapy in light of unfolding evidence., Sources: A search of the English language literature was conducted using the PubMed database from the National Library of Medicine. Bibliographies of retrieved articles were used to retrieve additional articles., Principal Findings: The advent of multiple safety steps has led to a dramatic reduction in the incidence of local anesthetic toxicity over the past 30 years. Rising plasma levels of local anesthetic lead to a progressive spectrum of neurological and cardiac effects. Seizure activity may herald the onset of myocardial depression and ventricular arrhythmias that are often refractory to treatment. In addition to specific measures, such as lipid emulsion therapy, general supportive measures are warranted, for example, Advanced Life Support Guidelines., Conclusion: Vigilance during the performance of regional anesthesia and immediate intervention at the earliest sign of toxicity improve the chances of successful treatment.

Purpose: To determine the effect of adjunctive epidural local anesthetic and opioid infusion on disease recurrence following radical prostatectomy for adenocarcinoma under general anesthesia., Methods: This article describes a secondary analysis of subjects undergoing radical prostatectomy who had participated previously in a randomized controlled trial evaluating pain control, blood loss, and the need for perioperative allogeneic blood transfusion. The patients were randomly allocated to receive either general anesthesia alone (control group; n = 50) or combined general/epidural anesthesia (study group; n = 49). A long-term follow-up chart review was undertaken to determine clinically evident or biochemical (Prostate Specific Antigen > 0.2 ng x mL(-1)) recurrence of prostate cancer. Comparison by group was undertaken using survival analysis., Results: Median disease-free survival for the study as a whole was 1644 days, and the longest recorded survival was 3403 days. Biochemical recurrence of prostate cancer was observed in 11/49 study subjects and 17/50 control subjects. There was one death from prostate cancer in each group and a total of five deaths in the study group and six deaths in the control group. The hazard ratio for recurrence in the study group compared with the control group was 1.33 (95% confidence intervals 0.64-2.77; P = 0.44 by log-rank test)., Conclusion: No difference was observed between the epidural and control groups in disease-free survival at a median follow-up time of 4.5 years. There is a need for large randomized controlled trials to determine the ability of epidural analgesia to alter disease recurrence rates following radical prostatectomy.

Objective: To observe pain management practices by nurses in emergency departments (EDs) in Central Africa and to study the various factors influencing these practices., Methods: Time to first analgesic treatment was recorded in 53 patients presenting to the ED of a Central African hospital in February 2005. A survey was simultaneously conducted on the attitudes and commitment of nurses towards the management of pain. All 28 nurses assigned to the ED agreed to participate in the survey., Results: Severity of pain was the factor most influencing the time to first analgesia following admission to the ED. Severe pain was assessed as a score of > or = 7 on a 1-10 visual analogue scale. The median time to first analgesia in patients with severe pain was 150 min, which was considerably longer than in patients without severe pain (p = 0.003). A quarter of the 28 nurses had no official training in pain management and most (> 80%) were unable to carry out a formal assessment of pain. The majority (> 90%) were confident of their ability to treat pain. Thirteen (48%) were of the opinion that cultural factors influenced their management of pain and 67% admitted that they had some fears about administering morphine to patients in the ED., Conclusion: Pain management by nurses in the ED in Central Africa is inadequate. Cultural factors greatly influence how nurses manage pain in the emergency room. Patients would benefit considerably if nurses received additional education about the diagnosis and management of acute pain in EDs in Central Africa.

Purpose: Radical prostatectomy is associated with substantial blood loss frequently requiring allogeneic blood transfusion. We investigated the efficacy of deliberate hypotension using combined epidural/general anesthesia in reducing allogeneic transfusion requirements in patients undergoing radical prostatectomy., Methods: In a prospective, randomized, single-blind trial, 102 patients undergoing radical prostatectomy were allocated to either an epidural group (n = 51) or a control group (n = 51). In the epidural group, deliberate hypotension was achieved with a target mean arterial pressure of 55-60 mmHg. The trigger for allogeneic blood transfusion in both groups was a hematocrit value < 0.25., Results: Operative blood loss in the epidural group was significantly less than that in the control group (955 +/- 517 mL vs 1477 +/- 823 mL respectively, P < 0.001). The percentage of patients who reached the threshold trigger for allogenic transfusion was significantly less in the epidural group (8% vs 26%, respectively, P = 0.019) and the number of patients who were actually transfused during hospitalization was also significantly less (P = 0.028). There were no serious adverse events in either group during the study., Conclusion: Controlled hypotension using a combined epidural/ general anesthetic technique is associated with significantly less blood loss, and a reduction in the use of allogeneic blood in patients undergoing radical prostatectomy compared to general anesthesia alone.

Purpose: The research productivity was estimated by publications from anesthesiology departments at Canadian universities over a five-year period, and the articles published were classified into several study designs., Methods: In this observational study, the MEDLINE database was searched for publications listed by anesthesiology departments at Canadian universities as the primary corresponding source from 2000-2004. Abstracts were reviewed and each publication categorized into its respective methodological design. Impact factors of the journals in which the articles appeared were taken into consideration. "Total impact score" was defined as the total number of articles from a particular journal in a particular year multiplied by the impact factor value. Changes in overall publication numbers over the five-year period were compared and analyzed using Pearson correlation coefficients., Results: Total Canadian anesthesia publications remained constant from 2000-2004. In this five-year time frame, the University of Toronto had the highest number of publications (271) followed by the University of Montreal (86), and McGill University (84). These universities conducted primarily randomized controlled trials (RCTs) whereas smaller Canadian universities mainly published case reports, reviews, and cohort studies. The number of RCTs conducted seems to be decreasing whereas the number of case reports and reviews being published are remaining constant over the five-year period., Conclusion: Although overall numbers in anesthesia publications do not suggest a significant decline, the number of RCTs decreased during the years 2000-2004. The quality of anesthesia research appears to be comparable to those in other medical specialties, with larger institutions conducting RCTs and smaller institutions publishing more case reports.

Purpose: To explore the possibility that the prolonged duration of anesthesia following paravertebral block was related to the presence of multiple sclerosis in a patient undergoing elective inguinal hernia repair., Clinical Features: A healthy 33-yr-old female presented for elective inguinal hernia repair. The procedure was performed under general anesthesia and a paravertebral block was performed at the end of the procedure for postoperative pain relief, whilst the patient was still anesthetized. Upon recovering from general anesthesia it was noted that the patient had a flaccid paralysis of both lower extremities. She was also very nauseated and required antiemetics and vasopressors for hypotension. A differential diagnosis of subarachnoid, subdural or epidural spread was considered. The presence of an epidural hematoma was also considered. The block regressed very slowly with full return of function in 12.5 hr. The duration of action of the block was far longer than one would expect following spinal, epidural or subdural spread of a local anesthetic. Urinary catheterization was performed electively to prevent urinary retention. The patient was discharged home late that evening. Prior to discharge she volunteered that she was being investigated for multiple sclerosis. One month later the diagnosis of multiple sclerosis was confirmed., Conclusion: In conclusion the extended duration of central neural blockade following paravertebral block, may have been related to an abnormal uptake of local anesthetics into the spinal cord in the presence of demyelination.

Purpose: The purpose of this study was to determine if the application of a BURP maneuver to the cricoid cartilage would combine the benefits of both the BURP and the Sellick maneuvers, resulting in an improved glottic view and offer the potential of protection against passive gastric regurgitation., Methods: This was a double-blind, prospective, randomized, crossover trial. Forty-three patients scheduled for elective surgery participated in this study. General anesthesia was induced using fentanyl, propofol and rocuronium. In a random sequence for each case and blinded to the laryngoscopist, one of three maneuvers was carried out. Direct vertical pressure, using 30 newtons, a BURP maneuver with cricoid pressure, or no pressure was applied to the cricoid and the laryngoscopic view was ascertained. A separate laryngoscopy was conducted for each maneuver and the views were graded as good (part of the glottis seen), poor (only the arytenoids were seen) or no view (only the epiglottis was seen). Endotracheal intubation was then performed in each case., Results: The results showed that the combination of the BURP maneuver and cricoid pressure worsened the view obtained at laryngoscopy in 30% of cases (P = 0.007). Cricoid pressure alone worsened the view in 12.5% of cases (P = 0.279). No difference was seen in 65% of cases. All patients but one were intubated easily., Conclusion: There is no benefit to routinely applying a modified "BURP" maneuver to the cricoid cartilage during rapid sequence induction of anesthesia.

Purpose: Using electrical epidural stimulation, a current of 1 to 10 mA is required to confirm the presence of the tip of an epidural catheter in the epidural space. The purpose of this study was to examine the hypothesis that the threshold current required to elicit a motor response in the intrathecal space is significantly lower than that in the epidural space in a porcine model., Methods: Four 20-kg pigs were used in this experiment. Eighteen gauge, insulated, Tuohy needles were advanced into the epidural space using the loss of resistance technique at five different spinal levels in each pig. When the epidural space was entered, an electrical current was applied to the needle and increased progressively until a motor response was elicited. The needle was then further advanced until cerebrospinal fluid (CSF) was observed or until the needle had been advanced a maximum of 1 cm. At this point, the current was reapplied and increased until motor activity was evident., Results: A total of 20 needles were inserted in four pigs. The current required to produce a motor response in the epidural space was 3.45 +/- 0.73 mA (mean +/- SD). The current required to produce a motor response in the intrathecal space (entry confirmed by the presence of CSF) was 0.38 +/- 0.19 mA (mean +/- SD). Two needles were advanced 1 cm without obtaining CSF but the current thresholds were similar to those obtained when CSF was evident (0.4 mA and 0.3 mA, respectively)., Conclusion: The threshold current of an insulated needle required to elicit a motor response in the intrathecal space, was significantly (P < 0.01) lower than that in the epidural space in a porcine model.

Background and Objectives: A small volume of local anesthetic or normal saline abolishes the muscle twitch induced by a 1ow current (0.5 mA) during electrolocation. This study examines the hypothesis that the mechanism of this phenomenon is primarily the electrophysiologic effect of the injectate on the electrical current density at the needle tip., Methods: Five pigs were studied. An insulated Tuohy needle was inserted in each pig toward the left and right brachial plexuses and the left and right femoral nerves. The needle was advanced until corresponding motor responses were observed at each site, using a current of 0.5 mA. The effect of injecting 1 mL each of normal saline and 5% dextrose in water (NS and D5W) on muscle twitch was investigated at all 20 needle insertion sites. Changes in the conductive area induced by the injectates were also demonstrated using gel electrophoresis., Results: In all cases, the muscle twitches were abolished immediately after the injection of NS and recovered instantaneously after a subsequent injection of D5W. The electrical resistance between the needle and the ground electrodes decreased instantly after the NS injection. The resistance not only recovered but also increased after the injection of D5W. In the gel electrophoresis experiment, the results demonstrated that the expanded conductive area induced by the saline column surrounding the insulated needle was similar to that observed with the uninsulated needle., Conclusion: The injection of a conducting solution (i.e., NS) rendered the current that was previously sufficient to elicit a motor response (0.5 mA) ineffective. The most likely reason for this change is that the conductive area surrounding the stimulating needle expanded after the injection and dispersion of the conducting solution (i.e., NS), thereby reducing the current density at the target nerve. This effect can be reversed by injecting a nonconducting solution (i.e., D5W) via the stimulating needle.

Background and Objectives: The public is not well informed about matters relating to regional anesthesia. Previous studies concerning regional anesthesia have involved patients, surgeons, and anesthesiologists. This study is the first in-depth survey of the attitudes of the general public toward a number of commonly perceived fears about regional anesthesia., Methods: A province-wide telephone survey was conducted in Alberta, Canada. The sample surveyed was representative of the adult population of the province and included an equal balance of urban and rural participants. General and regional anesthesia were defined, a scenario involving major knee surgery was described, and participants were asked to choose between regional and general anesthesia. Respondents were then questioned so their attitudes toward commonly perceived fears associated with regional anesthesia could be assessed., Results: A total of 1,216 people were surveyed. A preference for regional or general anesthesia was not expressed in this scenario. Approximately 27% of respondents were very concerned about permanent paralysis, back injury, perioperative pain, seeing the surgical procedure, and the prospect of a needle in the back. Only 6% of individuals were concerned about headaches., Conclusions: The public's fears and conceptions about regional anesthesia are greatly distorted. The anesthesia community has not been successful in keeping the public informed about regional anesthesia. Future anesthesia-related educational programs should address the concerns of the public about anesthesia matters, particularly regional anesthesia.

In continuous epidural anaesthesia we rely heavily on the 'test dose' to confirm correct placement of the catheter. This is not always accurate and there are a number of new techniques designed to provide better information about epidural needle and catheter placement. These include: electrical stimulation of the catheter, use of ultrasound and the application of simple geometry. The use of epidurals in patients undergoing coronary artery bypass graft surgery is controversial because of the risk of vertebral canal haematoma. Neurological complications may arise during administration of the block, since the needle or catheter may result in direct nerve trauma. The injection of irritant drugs can also cause neurological damage. We must therefore be meticulous when injecting drugs into the epidural space. The increasing use of anticoagulant therapy in surgical patients and, in particular, the variety of low molecular weight heparins available, may make it difficult to safely perform epidural anaesthesia.