Bacteria isolated from conspecific bite wounds in Norway and black rats: implications for rat bite-associated infections in people.

Bites associated with wild and domestic Norway and black rats (Rattus norvegicus and Rattus rattus) may have a variety of health consequences in people. Bite-related infections are among the most significant of these consequences; however, there is little data on the infectious agents that can be transmitted from rats to people through biting. This is problematic because without an accurate understanding of bite-related infection risks, it is difficult for health professionals to evaluate the adequacy of existing guidelines for empirical therapy. The objectives of this study were to increase our knowledge of the bacterial species associated with rat bites by studying bite wounds that wild rats inflict upon one another and to review the literature regarding rat bites and bite wound management. Wild Norway and black rats (n=725) were trapped in Vancouver, Canada, and examined for bite wounds in the skin. All apparently infected wounds underwent aerobic and anaerobic culture, and isolated bacteria were identified. Thirty-six rats had bite wound-related infections, and approximately 22 different species of bacteria belonging to 18 genera were identified. Staphylococcus aureus was the most common isolate; however, the majority of infections (72.5%) were polymicrobial. Rat bites can result in infection with a number of aerobic and anaerobic Gram-positive and Gram-negative bacteria. In humans, these wounds are best managed through early recognition and cleansing. The benefit of prophylactic antimicrobial treatment is debatable, but given the deep puncturing nature of rodent bites, we suggest that they should be considered a high risk for infection. Antibiotics selected should include coverage for a broad range of bacterial species.

Intranasal ketamine for analgesia in the emergency department: a prospective observational series.

OBJECTIVES: The objective was to examine the feasibility, effectiveness, and adverse effect profile of intranasal ketamine for analgesia in emergency department (ED) patients. METHODS: This was a prospective observational study examining a convenience sample of patients aged older than 6 years experiencing moderate or severe pain, defined as a visual analog scale (VAS) score of 50 mm or greater. Patients received 0.5 to 0.75 mg/kg intranasal ketamine. Pain scores were recorded on a standard 100-mm VAS by trained investigators at baseline, then every 5 minutes for 30 minutes, and then every 10 minutes for an additional 30 minutes. The primary outcome was the number and proportion of patients experiencing clinically significant reductions in VAS pain scores, defined as VAS reductions of 13 mm or more, within 30 minutes. Secondary outcomes included the median reduction in VAS, the median time required to achieve a 13 mm reduction in VAS, vital sign changes, and adverse events. Continuous data are reported with medians and interquartile ranges (IQRs). The Wilcoxon signed-ranks test was used to assess changes in VAS scores. Adverse effects are reported with proportions and 95% confidence intervals (CIs). RESULTS: Forty patients were enrolled with a median age of 47 years (IQR = 36 to 57 years; range = 11 to 79 years) for primarily orthopedic injuries. A reduction in VAS of 13 mm or more within 30 minutes was achieved in 35 patients (88%). The median change in VAS at 30 minutes was 34 mm (44%). Median time required to achieve a 13 mm VAS reduction was 9.5 minutes (IQR = 5 to 13 minutes; range = 5 to 25 minutes). No serious adverse effects occurred. Minor adverse effects included dizziness (21 patients, 53%; 95% CI = 38% to 67%), feeling of unreality (14 patients, 35%; 95% CI = 22% to 50%), nausea (four patients, 10%; 95% CI = 4% to 23%), mood change (three patients, 8%; 95% CI = 3% to 20%), and changes in hearing (one patient, 3%; 95% CI = 0% to 13%). All adverse effects were transient and none required intervention. There were no changes in vital signs requiring clinical intervention. CONCLUSIONS: Intranasal ketamine reduced VAS pain scores to a clinically significant degree in 88% of ED patients in this series. Adverse effects were minor and transient. Intranasal ketamine may have a role in the provision of effective, expeditious analgesia to ED patients.