A Web-based Educational Intervention to Increase Perianesthesia Nurses' Knowledge, Attitude, and Intention to Promote Safe Use, Storage, and Disposal of Opioids.

PURPOSE: The purpose of this study was to determine if a web-based educational intervention increased knowledge, attitudes, and intention of perianesthesia nurses regarding opioid discharge education (including safe use, storage, and disposal of opioids). Secondary outcomes were to determine Perceived Behavioral Control, subjective norms, and familiarity with American Society of PeriAnesthesia Nurses (ASPAN) guidance on opioid education. DESIGN: A pre-test, post-test longitudinal design. METHODS: An email described the study and had a link for those choosing to participate. The intervention was a web-based voiceover module with patient education scenarios focused on information required for patients before discharge home. Responses to the evidence-based pre-survey, post-survey one, and post-survey two were collected. The survey was developed using components of the Theory of Planned Behavior. Data analysis included descriptive summary and evaluation of changes in knowledge and domains of Theory of Planned Behavior using repeated measures mixed modeling. FINDINGS: The participants were invited to complete a pre-test survey (n = 672), the immediate post-test (n = 245), and the 4-week post-test (n = 172). The analysis presented is limited to 245 who completed at least the first post-survey. Most were staff nurses (82%), and the majority had a BSN (62%); participants most typically worked in a hospital-based PACU (73%). For all outcomes, there was an immediate increase in the measure following the intervention; this pairwise difference (between pretest and the immediate post-test) was significant in all but one of the models. The immediate and 4-week post-test scores exceeded the corresponding pre-test score, though for Perceived Behavioral Control, attitude, and intention, the degree of increase between baseline and week 4 was not significant. CONCLUSIONS: In all cases, both the immediate and 4-week post-test scores exceeded the corresponding pre-test score, though, for three of the TPB constructs, the difference between baseline and week 4 was not significant, while nearly all of the increases between baseline and immediately following the intervention were significant. These findings suggest a more intensive intervention, possibly with the inclusion of booster sessions, may be needed.

Perianesthesia Patient Education for the Promotion of Opioid Stewardship.

Opioid overdose deaths and opioid use disorders are a crisis in the United States and other western countries around the globe. Opioid prescriptions more than doubled after the turn of the century, particularly for postoperative patients. Unfortunately, many who have abused opioids were able to obtain those opioids from friends or family who had held on to prescribed, but unused opioids. One method to manage and decrease the opportunity for unused opioids to become black-market opioids is to educate patients and families regarding the safe use, safe storage, and proper disposal of unused prescription opioids. Perianesthesia nurses, particularly those who educate patients before and after surgery, have an excellent opportunity to educate patients and families who are discharged to home after surgery.

Opioid Use in Chronic Pain Patients with Chronic Kidney Disease: A Systematic Review.

OBJECTIVES: To investigate the prevalence of chronic pain and opioid management among patients with chronic kidney disease (CKD). DESIGN: Systematic review. METHODS: A systematic search was performed, including citations from 1960 to May 2015. The review highlights methodological quality assessment of the selected studies; prevalence of pain; type, dose, and reason for opioid use; effectiveness of pain control and associated adverse effects of opioids in CKD patients. RESULTS: Twelve of 131 articles met inclusion criteria. There were no randomized controlled trials (RCT) evaluable, and 12 were observational studies. Out of 12 studies, four were of high quality, six were of moderate quality, and the remaining two were low-quality studies. The studies were from different countries with sample size ranging from 10 to 12,782. Several studies showed a high prevalence of chronic uncontrolled pain. The effectiveness of different categories of opioids, dose, duration, and commonly prescribed opioids varied across studies. CONCLUSIONS: Based on a systematic review of the current literature, there is fair evidence for the high prevalence of chronic pain among patients with CKD, which is not being effectively managed, probably due to underprescription of analgesics or opioids in the CKD population. Clinicians are in need of additional and well-designed randomized control trials that focus on the indications for opioid therapy, appropriate opioid doses and dosing intervals, outcomes with adequacy of symptom control, and reporting on the incidence of adverse side effects.

A randomized, double-blind trial comparing continuous thoracic epidural bupivacaine with and without opioid in contrast to a continuous paravertebral infusion of bupivacaine for post-thoracotomy pain.

OBJECTIVE: To compare the results of continuous epidural bupivacaine analgesia with and without hydromorphone to continuous paravertebral analgesia with bupivcaine in patients with post-thoracotomy pain. DESIGN: A prospective, randomized, double-blinded trial. SETTING: A teaching hospital. PARTICIPANTS: Patients at a tertiary care teaching hospital undergoing throracotomy for lung cancer. INTERVENTIONS: Subjects were assigned randomly to receive a continuous thoracic epidural or paravertebral infusion. Patients in the epidural group were randomized to receive either bupivacaine alone or in combination with hydromorphone. Visual analog scores as well as incentive spirometery results were obtained before and after thoracotomy. METHODS AND MAIN RESULTS: Seventy-five consecutive patients presenting for thoracotomy were enrolled in this institutional review board-approved study. On the morning of surgery, subjects were randomized to either an epidural group receiving bupvicaine with and without hydromorphone or a paravertebral catheter-infused bupvicaine. Postoperative visual analog scores and incentive spirometry data were measured in the postanesthesia care unit, the evening of the first operative day, and daily thereafter until postoperative day 4. Analgesia on all postoperative days was superior in the thoracic epidural group receiving bupivacaine plus hydromorphone. Analgesia was similar in the epidural and continuous paravertebral groups receiving bupivacaine alone. No significant improvement was noted by combining the continuous infusion of bupivacaine via the paravertebral and epidural routes. Incentive spirometry goals were best achieved in the epidural bupivacaine and hydromorphone group and equal in the group receiving bupivacaine alone either via epidural or continuous paravertebral infusion. CONCLUSIONS: The current study provided data that fill gaps in the current literature in 3 important areas. First, this study found that thoracic epidural analgesia (TEA) with bupivacaine and a hydrophilic opioid, hydromorphone, may provide enhanced analgesia over TEA or continuous paravertebral infusion (CPI) with bupivacaine alone. Second, in the bupivacaine-alone group, the increased basal rates required to achieve analgesia resulted in hypotension more frequently than in the bupivacaine/hydromorphone combination group, underscoring the benefit of the synergistic activity. Finally, in agreement with previous retrospective studies, the current data suggest that CPI of local anesthetic appears to provide acceptable analgesia for post-thoracotomy pain.

Acute administration of oxycodone, alcohol, and their combination on simulated driving-preliminary outcomes in healthy adults.

RATIONALE: Epidemiological data indicate that drivers testing positive for an opioid drug are twice as likely to cause a fatal car crash; however, there are limited controlled data available. OBJECTIVES: The primary aim of this study was to assess the effects of a therapeutic dose range of oxycodone alone and in combination with alcohol on simulated driving performance. METHODS: Healthy participants (n = 10) completed this within-subject, double-blind, placebo-controlled, randomized outpatient study. Six 7-h sessions were completed during which oxycodone (0, 5, 10 mg, p.o.) was administered 30 min before alcohol (0, 0.8 g/kg (15% less for women), p.o.) for a total of 6 test conditions. Driving assessments and participant-, observer-rated, psychomotor and physiological measures were collected in regular intervals before and after drug administration. RESULTS: Oxycodone alone (5, 10 mg) did not produce any changes in driving outcomes or psychomotor task performance, relative to placebo (p > 0.05); however, 10 mg oxycodone produced increases in an array of subjective ratings, including sedation and impairment (p < 0.05). Alcohol alone produced driving impairment (e.g., decreased lateral control) (p < 0.05); however, oxycodone did not potentiate alcohol-related driving or subjective effects. CONCLUSIONS: These preliminary data suggest that acute doses of oxycodone (5, 10 mg) do not significantly impair acuity on laboratory-based simulated driving models; however, 10 mg oxycodone produced increases in self-reported outcomes that are not compatible with safe driving behavior (e.g., sedation, impairment). Additional controlled research is needed to determine how opioid misuse (higher doses; parenteral routes of administration) impacts driving risk.

Cannabinoid modulation of opioid analgesia and subjective drug effects in healthy humans.

RATIONALE: Dozens of preclinical studies have reported cannabinoid agonist potentiation of the analgesic effects of µ-opioid agonists. OBJECTIVES: The aim of this study was to determine if a cannabinoid agonist could potentiate opioid analgesia in humans using several laboratory pain models. METHODS: Healthy participants (n = 10) with/out current drug use/pain conditions completed this within-subject, double-blind, placebo-controlled, randomized outpatient study. Nine 8-h sessions were completed during which dronabinol (0, 2.5, 5 mg, p.o.) was administered 1 h before oxycodone (0, 5, 10 mg, p.o.) for a total of 9 test conditions. Outcomes included sensory threshold and tolerance from four experimental pain models (cold pressor, pressure algometer, hot thermode, cold hyperalgesia), along with participant- and observer-rated, performance and physiological effects. RESULTS: Oxycodone produced miosis (p < 0.05) and analgesic responses (e.g., pressure algometer [p < 0.05]), while dronabinol did not (p > 0.05). Depending on the dose combination, dronabinol attenuated or did not alter oxycodone analgesia; for example, dronabinol (2.5 mg) decreased the analgesic effects of oxycodone (10 mg) on pressure tolerance. Conversely, dronabinol increased oxycodone subjective effects (e.g., drug liking) (p < 0.05); oxycodone (5 mg) ratings of "high" were potentiated by 5 mg dronabinol (p < 0.05; placebo = 1.1 [± 0.7]; 5 mg oxycodone = 4.7 [± 2.2]; 5 mg dronabinol = 9.9 [± 8.4]; 5 mg oxycodone + 5 mg dronabinol = 37.4 [± 11.3]). CONCLUSIONS: This study indicates that dronabinol did not enhance the analgesic effects of oxycodone and increased abuse- and impairment-related subjective effects. These data suggest that dronabinol may not be an effective or appropriate opioid adjuvant; it could potentially increase opioid dose requirements, while increasing psychoactive opioid effects.

Cognitive aid use improves transition of care by graduating medical students during a simulated crisis.

BACKGROUND: Residents are expected to have transition of care (ToC) skills upon entering graduate medical education. It is unclear whether experience and training during medical school is adequate. OBJECTIVE: The aim of the project was to assess: 1) graduating medical students' ability to perform ToC in a crisis situation, and 2) whether using a cognitive aid improves the ToC quality. METHODS: The authors developed simulation scenarios for rapid response teams and a cognitive aid to assist in the ToC during crisis situations. Graduating medical students were enrolled and randomly divided into teams of three students, randomly assigned into one of two groups: teams using a cognitive aid for ToC (CA), or not using a cognitive aid (nCA). In the scenario, teams respond to a deteriorating patient and then transfer care to the next provider after stabilization. Three faculty reviewed the recording to assess completeness of the ToC and the overall quality. A completeness score was expressed as a fraction of the maximum score. Statistical analysis was performed using a t-test and Mann-Whitney U test. RESULTS: A total of 112 senior medical students participated: CA n=19, nCA n=17. The completeness score of the ToC and overall quality improved when using the cognitive aid (completeness score: CA 0.80±0.06 vs. nCA 0.52±0.07, p<0.01; ToC quality: CA 3.16±0.65 vs. nCA 1.92±0.56, p<0.01). Participants' rating of knowledge and comfort with the ToC process increased after the simulation. CONCLUSION: The completeness of information transfer during the ToC process by graduating medical students improved by using a cognitive aid in a simulated patient crisis.

Systemic-to-pulmonary artery pressure ratio as a predictor of patient outcome following liver transplantation.

AIM: To assess the value of the mean systemic-to-pulmonary artery pressure (MAP/mPAP) ratio for predicting outcomes following orthotopic liver transplant (OLT). METHODS: A retrospective data analysis was performed and data (mean arterial blood pressure, mean pulmonary artery pressure and Cardiac Index) were collected at several points during OLT. Outcomes evaluated were duration of postoperative endotracheal intubation [ET; minutes after intensive care unit (ICU) arrival], length of ICU stay, total hospitalization and frequency of immediate postoperative complications. A total of 91 patients were included in the data analysis. Based on the intraoperative course of the MAP/mPAP ratio, 2 hemodynamic responses were identified: Group 1 (MAP/mPAP ratio increase during anhepatic period with postreperfusion recovery, n = 66); and Group 2 (MAP/mPAP ratio with no change during anhepatic period or decreased without recovery, n = 25). RESULTS: The main finding was that the lack of increased MAP/mPAP ratio in the anhepatic period was associated with: (1) longer intubation times; and (2) prolonged ICU stays and total hospitalization time, when compared to patients with an increase in MAP/mPAP ratio during the anhepatic period. CONCLUSION: The data from this retrospective study should raise awareness to the mean systemic to pulmonary artery pressure ratio as a potential indicator for poor outcome after OLT. Further prospective studies are needed for validation.

Perioperative pain management education: a short structured regional anesthesia course compared with traditional teaching among medical students.

BACKGROUND AND OBJECTIVES: Previous research has demonstrated that a brief course on pain management improved knowledge and attitudes toward analgesic use among medical students. The purpose of this study is to compare a structured clinical instruction course on regional anesthesia techniques for perioperative pain management with traditional teaching given to senior medical students. METHODS: During a 1-month clerkship in anesthesiology, 40 fourth-year medical students were randomly and equally divided into 2 groups. The study group received a 2-hour structured course on regional anesthesia techniques for pain management, whereas the control group received a 1-hour lecture tutorial on regional anesthesia techniques for perioperative pain management and 1 hour of bedside teaching on acute pain management. Each student completed an objective structured clinical examination (OSCE) 2 weeks after completion of the course. RESULTS: The study group performed better on each of the 11 items of the OSCE and on the total performance scores (mean +/- SD of 36.2 +/- 7.3 for study group versus 14.8 +/- 8.4 for the control group; P < .05). All students rated the clinical course highly valuable (4.7 +/- 0.5). CONCLUSION: A structured clinical instructional course on regional techniques for perioperative pain management given to fourth-year medical students can significantly improve their understanding and knowledge compared with traditional teaching.

Hypogonadism associated with long-term opioid therapy: A systematic review.

BACKGROUND: Sexual dysfunction and Opioid-Induced Sexual Hormone Deficiency (OPISHD) have been associated with patients on long-term opioid pain therapy. There have been few comprehensive reviews to establish a relation between hypogonadism with chronic opioid pain management. The OPISHD is often not treated and literature guiding this topic is scarce. OBJECTIVE: To investigate hypogonadism associated with long-term opioid therapy based on qualitative data analysis of the available literature. STUDY DESIGN: Systematic review. INTERVENTIONS: The review included relevant literature identified through searches of PubMed, Cochrane, Clinical Trials, US National Guideline Clearinghouse, and EMBASE, for the years 1960 to September 2013. The quality assessment and clinical relevance criteria used were the Cochrane Musculoskeletal Review Group Criteria for randomized control trials and the Newcastle-Ottawa Scale Criteria for observational studies. The level of evidence was classified as good, fair, and poor, based on the quality of evidence. MAIN OUTCOME MEASURES: The primary outcome measures were clinical symptoms and laboratory markers of hypogonadism. Secondary outcome measure was management of OPISHD. RESULTS: Thirty-one studies were identified, of which 14 studies met inclusion criteria. There were no randomized control trials and eight of 14 studies were of moderate quality. The remaining studies were of poor quality. Four studies report most patients on long-term oral opioid therapy have associated hypogonadism and three studies of patients receiving intrathecal opioid therapy suggest that hypogonadism is common. CONCLUSIONS: There is lack of high-quality studies to associate chronic opioid pain management with hypogonadism. At present, there is fair evidence to associate hypogonadism with chronic opioid pain management, and only limited evidence for treatment of OPISHD.

The impact of exposure to liver transplantation anesthesia on the ability to treat intraoperative hyperkalemia: a simulation experience.

The objective of this study was to assess whether resident exposure to liver transplantation anesthesia results in improved patient care during a simulated critical care scenario. Our hypothesis was that anesthesia residents exposed to liver transplantation anesthesia care would be able to identify and treat a simulated hyperkalemic crisis after reperfusion more appropriately than residents who have not been involved in liver transplantation anesthesia care. Participation in liver transplantation anesthesia is not a mandatory component of the curriculum of anesthesiology training programs in the United States. It is unclear whether exposure to liver transplantation anesthesia is beneficial for skill set development. A high-fidelity human patient simulation scenario was developed. Times for administration of epinephrine, calcium chloride, and secondary hyperkalemia treatment were recorded. A total of 25 residents with similar training levels participated: 13 residents had previous liver transplantation experience (OLT), whereas 12 residents had not been previously exposed to liver transplantations (non-OLT). The OLT group performed better in recognizing and treating the hyperkalemic crisis than the non-OLT group. Pharmacologic therapy for hyperkalemia was given earlier (OLT 53.3 ± 27.0 seconds versus non-OLT 148 ± 104.1 seconds; P < 0.01) and hemodynamics restored quicker (OLT 87.9 ± 24.9 seconds versus non-OLT 219.9 ± 87.1 seconds; P < 0.01). Simulation-based assessment of clinical skills is a useful tool for evaluating anesthesia resident performance during an intraoperative crisis situation related to liver transplantations. Previous liver transplantation experience improves the anesthesia resident's ability to recognize and treat hyperkalemic cardiac arrest.

Equipping medical students to manage cancer pain: a comparison of three educational methods.

A Cancer Pain Structured Clinical Instruction Module (SCIM), with skills stations incorporating actual cancer patients, has been developed to enhance cancer pain education among our medical students. The Cancer Pain SCIM has not been compared with more traditional cancer pain education, thus the purpose of this study was to assess the effectiveness and durability of three educational methods for teaching cancer pain management to medical students compared with a control group. Four consecutive rotations of 32 third-year medical students participated in one of four cancer pain educational strategies: 1) control group with no formal cancer pain education, 2) CD-ROM self-instruction module on cancer pain, 3) a 2-hour Cancer Pain SCIM plus the CD-ROM information, and 4) Cancer Pain SCIM, plus CD-ROM, plus a structured home-hospice patient visit. The effectiveness of the educational interventions was assessed at 4 months post-instruction using a 4-component Cancer Pain Objective Structured Clinical Examination (OSCE). The main findings of this educational study are that: 1) all three educational groups performed better on the Cancer Pain OSCE at 4 months than the control group (P<0.05); 2) medical students receiving structured education on cancer pain management significantly out-performed students at 4 months compared with control or traditional instructional formats; 3) students receiving the Cancer Pain SCIM plus home visit performed highest on the pain management, physical exam, and communication stations of the OSCE; and 4) the SCIM format of education shows durability as assessed at 4 months post-instruction. The Cancer Pain SCIM has a unique potential to substantially improve the quality of cancer pain education.

The evolving role of interventional pain management in oncology.

Patients with cancer frequently experience chronic pain, especially in the terminal phases of illness. Fortunately, most patients (90%) can achieve good pain relief using standard and adjuvant analgesics. For those patients who experience severe pain resistant to traditional analgesic therapies, interventional pain management techniques often provide welcome pain relief. The use of neurolytic substances has been used for many decades but has found a niche in the treatment of pain related to abdominal and pelvic cancers. Simple, percutaneous injections of alcohol or phenol can provide much needed pain relief for patients with pancreatic, colon, or gynecologic cancers. The percutaneous placement of catheters for the chronic infusion of spinal analgesics can provide pain relief for virtually any part of the body. Internal or external infusion pumps can be well managed at home, improving quality of life. The physician treating the pain should be aware of these and other interventional pain management techniques to provide alternative therapies to patients with refractory cancer pain.

Treatment of neuropathic orbital pain with gabapentin.

We report and discuss a case of severe neuropathic orbital pain refractory to standard analgesics that responded well to treatment with the anticonvulsant gabapentin. Gabapentin may be a useful adjuvant analgesic in the treatment of neuropathic pain.

Ultralow dose fentanyl prevents development of chronic neuropathic pain in rats.

BACKGROUND: Opioids may cause progressive enhancement of pain sensitivity (opioid-induced hyperalgesia [OIH]) and thus, exacerbate existing pain. Animal studies also demonstrate paradoxical OIH with an ultralow dose (ULD, subanalgesic) of opioid; eg, the µ-opioid, morphine. Repeated administration of ULD-morphine resulted in tolerance to ULD-OIH. Prior exposure to ULD-morphine prolonged subsequent morphine antinociception in intact rats (delay of tolerance) and blocked neuropathic pain in nerve-injured rats (no hyperalgesia). Hence, pre-emptive desensitization of the excitatory function of opioid receptors may reduce further activation of a pain facilitatory system exerted by opioid or nerve injury. OBJECTIVE: We determined if ULD-fentanyl (µ-opioid) and U50488H (κ-opioid) also affect post-nerve-injury neuropathy (a rat model of chronic constriction nerve injury [CCI]). DESIGN: Fentanyl (0.5-500 ng/kg) was administered acutely in noninjured rats. Chronic fentanyl (5 ng/kg/day) was initiated either immediately after CCI (day 1-28) or when neuropathy was established (day 7-14) in nerve-injured rats. U50488H (25 µg/kg/day) was given on day 1-28 post-CCI. Saline served as control. Responsiveness was assessed using tail-flick and paw-pressure tests, respectively, in intact and CCI Sprague-Dawley rats of both sexes. RESULTS: ULD-fentanyl evoked pain sensitization in noninjured rats. ULD-OIH was related to dose (inversely), gender (female > male), and was reversed by ketamine. Neuropathy developed after CCI in control (saline) rats. This was not observed in rats of either sex exposed to ULD-fentanyl on day 1-28 post-CCI. Rats treated with ULD-fentanyl from day 7 after CCI exhibited hyperalgesia similar to control rats. U50488H did not block post-CCI neuropathy (regardless of gender). CONCLUSIONS: Pre-emptive use of ULD µ-opioid (not κ-opiod) blocked initiation (not maintenance) of neuropathic pain after CCI in rats. These data may suggest a novel treatment approach in situations when the potential development of neuropathy can be anticipated.

Trialing of intrathecal baclofen therapy for refractory stiff-person syndrome.

OBJECTIVE: Stiff-person syndrome (SPS) is a rare disorder of the central nervous system characterized by stiffness and muscle spasms that may be progressive in nature. When oral medication is inadequate to control muscle spasticity, intrathecal baclofen may be used. We report a patient with severe SPS and glutamate decarboxylase negative [GAD(-)] (note: GAD(-) indicates the patient has no antibodies to GAD), refractory to oral standard therapies. The patient was effectively trialed with an intrathecal catheter and subsequently treated with chronic intrathecal baclofen, which provided significant relief of spasticity symptoms. CASE REPORT: A 48-year-old white man with a history consistent with SPS presented to the clinic. His previous history showed that he met several diagnostic criteria for GAD(-) SPS and had a muscle biopsy positive for myositis. Oral medications were unable to control his muscle spasticity, preventing him from working. The patient received an intrathecal trial using a lumbar approach for placement of a thoracic catheter with an initial baclofen dose of 50 µg/d. Gradual titration to symptom relief was performed up to 150 µg/d. Functional evaluation by our physical therapist showed improved motor function, the temporary catheter was removed, and a permanent intrathecal pump placed for intrathecal baclofen infusion. The patient reported excellent symptom relief over the next 6 months and improved activity. CONCLUSIONS: Refractory SPS is difficult to treat and has few therapeutic options. We report a GAD(-) patient with SPS and resulting debilitating spasticity that was refractory to oral medications who underwent successful continuous intrathecal catheter trial of baclofen over 4 days and subsequently went on to implantation of intrathecal pump. The literature reports only 5 cases of GAD(-) SPS patients treated with intrathecal baclofen therapy, and these resulted in poor long-term success. Our patient completed a 4-day trial of intrathecal baclofen titrated to effect before pump implantation. We advocate continuous intrathecal trialing, as opposed to single-injection technique, to possibly better determine the effective therapeutic dose and ensure posttrialing successful therapy.

Effect of prior treatment with ultra-low-dose morphine on opioid- and nerve injury-induced hyperalgesia in rats.

BACKGROUND: In addition to producing analgesia, opioids can increase sensitivity to pain (opioid-induced hyperalgesia [OIH]) in humans and rodents. Tolerance/OIH is likely mediated by similar mechanisms that lead to development of hyperalgesia after nerve injury (neuropathic pain). OIH may be a reason for loss of opioid efficacy and/or a worsening of pain. Ultra-low-dose (ULD) opioid evokes hyperalgesia independently of analgesia. Tolerance to ULD-OIH develops with repeated dosing in rats. OBJECTIVE: The effects of ULD opioids were characterized in two distinct situations where hyperalgesia is expected to occur: following acute opioid treatment and after nerve injury. DESIGN: First, ULD morphine was repeatedly administered (2x day for 5 days) by intrathecal (i.t., 0.01 microg) or intraperitoneal (i.p., 20 microg/kg) routes in rats. Second, morphine (0.01 microg i.t.; 20 microg/kg i.p.) was administered (2x day for 5 days) prior to acute morphine (30 microg i.t.; 10 mg/kg i.p). Third, ULD morphine (20 microg/kg/2x day, i.p.) was given either immediately after nerve injury (days 1-28) or when hyperalgesia was manifested (days 7-14). The tail-flick and paw-pressure tests were used in noninjured and nerve-injured rats, respectively. RESULTS: Tolerance was developed to OIH with repeated ULD morphine by the i.p. route but not the i.t. route. Prior exposure to ULD morphine (i.p.) caused prolongation of morphine analgesia in intact rats and inhibition of the development (but not reversal) of hyperalgesia in nerve-injured rats. Abolishment of OIH (pain desensitization) may diminish activation of pain facilitatory systems due to nerve injury and opioid treatment. CONCLUSIONS: Although the translational aspect of this preclinical study has limitations, the present data may suggest a new strategy for the pre-emptive use of ULD opioids to prevent the development of neuropathic pain with certain procedures or disease states.

Neurophysiological monitoring simulation using flash animation for anesthesia resident training.

INTRODUCTION: Surgery of the spine is associated with the possible complication of permanent nerve injury. Neurophysiological monitoring is widely used during spine surgery to decrease the incidence and severity of neurologic injury. A profound understanding of physiological and pharmacological factors influencing evoked potentials is expected from the anesthesia provider. METHODS: Because demonstration and teaching of all somatosensory evoked potential (SSEP) changes is difficult in the clinical environment, we developed human patient simulator scenarios to facilitate the anesthesia resident training in neurophysiological monitoring. A SSEP simulation for resident training was created using flash animation in a patient simulation program and is the focus of this report. Feedback from participants (anesthesia residents) was obtained by a postscenario survey. RESULTS: This report provides a detailed description of the scenario and computer program. The survey findings indicated that the simulation session is an effective teaching method of SSEP monitoring. CONCLUSION: Flash animation integration into a patient simulation program for SSEP monitoring appears to be an effective method for anesthesia resident education in neurophysiological monitoring.