Evaluation of Therapeutic Approaches for the Treatment of Spironucleus muris in Mice.

Spironucleus muris is an intestinal protozoal pathogen that can infect various species of rodents. The infection can have a wide range of clinical presentations, from no signs of disease to death. In addition, this pathogen can adversely affect research results, especially immunologic and gastrointestinal studies. For these reasons, institutions may exclude Spironucleus muris. However, despite rigorous efforts to keep this pathogen out, it can be common in rodent colonies. The current recommended approach to eradicating this pathogen is by testing and culling positive animals. A similar organism, Giardia muris, has been effectively eliminated by using chemotherapeutics. Therefore, the objective of this study was to determine whether S. muris is also susceptible to chemotherapeutics. Naturally infected mice were randomized to treatment groups after confirmation of positive infection via PCR. Mice received either metronidazole, fenbendazole, a combination of metronidazole-fenbendazole, or acidified water (control) treatments for a period of 4 wk. Each week fecal testing of S. muris was performed via PCR to evaluate the effectiveness of the treatments. At the end of the 4 wk period, mice were euthanized via CO2 inhalation and segments of the proximal gastrointestinal tract were submitted for histopathologic analysis. Treatment with metronidazole or fenbendazole alone or in combination, failed to clear S. muris infected mice. After 4 wk of treatment, none of the mice given fenbendazole via sucralose medicated gel were positive by either PCR or histopathology; however, this finding is most likely due to intermittent shedding rather than chemotherapeutic success. Therefore, the recommendation remains to test-and-cull or rederive mice as necessary to eliminate S. muris from laboratory animal facilities.

A Comparison of Buprenorphine, Sustained release Buprenorphine, and High concentration Buprenorphine in Male New Zealand White Rabbits.

Pain management in rabbits can be difficult because they are adept at hiding pain and can be stressed by handling and restraint for injection. The use of opioid analgesics with prolonged durations of activity could alleviate pain, but associated adverse effects including gastrointestinal ileus, inappetence, and tissue reactions have been reported. In this study, we compared gross tissue reactions at the site of injection, food consumption, and fecal production after single injections of buprenorphine HCl (Bup; n = 7), sustained-release buprenorphine (BupSR; n = 8), and high-concentration buprenorphine (BupHC; n = 7) during the first 3 d after minor survival surgery. We also measured plasma concentrations of the parent drug, buprenorphine, and 3 metabolites (buprenorphine-3-glucuronide (B3G), norbuprenorphine-3ß-glucuronide (N3G), and norbuprenorphine (NB)). Plasma levels of buprenorphine remained above the theoretical minimal analgesic concentration for 4 h for Bup and 42 h for BupHC. For BupSR, plasma levels of buprenorphine remained above the theoretical minimal analgesic concentration for approximately 77 h, starting 15 h after administration. For all 3 formulations, N3G was the most prominent metabolite in the blood. No injection site reactions were visible grossly in any rabbit. Relative to baseline measures and compared with controls (n = 8), food consumption was suppressed on days 1 through 3 in rabbits that received BupSR and on days 2 through 3 in those given BupHC. Feces production on day 3 was reduced to a greater extent in BupSR rabbits than control animals. Two rabbits in the BupHC group exhibited neurologic signs after drug administration. These adverse effects should be considered when choosing a long-lasting buprenorphine formulation to manage pain in rabbits.

Efficacy and safety of procedural sedation and analgesia for burn wound care.

The study aim was to quantify efficacy and patient safety of registered nurse-administered procedural sedation and analgesia in a regional burn center. The investigators conducted a review of procedural sedation forms for all pediatric and adult patients admitted to this burn center from January 1, 2005, through December 31, 2005, for demographic and clinical data including patient age, gender, body weight, TBSA, dates of burn injury and wound care procedures, length of procedure, pre- and postprocedural pain assessment, procedural sedation/analgesia medications and doses, adverse drug events, and related interventions. During the 12-month study period, a total of 328 burn patients received 1293 procedural sedation procedures; child subjects (≤ 18 years) received 356 procedures and adult subjects (19-87 years) received 937 procedures. The mean (SD) length of the procedure was 60.1 (22.49) minutes with a range of 10 to 170 minutes. The mean subject age was 34.2 years (range: 6 weeks to 87 years), 67% were male, and the mean TBSA was 17% (0.5-68%). Ninety-four percent received fentanyl for analgesia and 85% received midazolam for anxiolysis and amnesia. The mean preprocedural pain score was 3.2 and the mean postprocedural pain score was 2 (t = 14.795; df = 1243; P < .001). Ten adverse events, all respiratory related, were documented in eight patients, two of whom experienced a second adverse event for an overall adverse event rate of 0.77%. No patient required intubation. Procedural sedation administered by a registered nurse competent in administration and monitoring in a burn center provided safe and effective pain management during wound care.