A randomized trial of loading vancomycin in the emergency department

BACKGROUND

Optimizing vancomycin dosing may help eradicate bacteria while avoiding resistance. The guidelines recommend loading doses; however, there are no data to demonstrate that this may result in a more rapid achievement of therapeutic troughs.

OBJECTIVE

To evaluate the percentage of troughs reaching therapeutic levels at 12, 24, and 36 hours following an initial vancomycin dose of 30 mg/kg compared with 15 mg/kg.

METHODS

This prospective, randomized study was performed in a community academic medical center. Patients who were to receive vancomycin in the emergency department were randomized to an initial traditional dose of 15 mg/kg or a 30-mg/kg loading dose followed by 15 mg/kg every 12 hours for 3 doses. Patients weighing >120 kg or with creatinine clearances <50 mL/min were excluded.

RESULTS

In total, 99 patients were enrolled; 12 hours after the initial dose of vancomycin, there was a significantly greater proportion of patients reaching target trough levels of 15 mg/L among the patients who received a loading dose as compared with a traditional dose (34% vs 3%, P < 0.01). This trend continued at 24 hours but was not statistically significant. At 36 hours, there was no difference in the percentage of patients reaching target levels between the 2 groups. No statistically significant difference in nephrotoxicity or adverse events among the 2 groups was demonstrated.

CONCLUSION

A loading dose of 30 mg/kg of vancomycin achieved a higher percentage of therapeutic levels at 12 hours when compared with the traditional dose of 15 mg/kg, without increased nephrotoxicity or adverse events.

Prescribing habits of vancomycin in the Emergency Department: are we dosing appropriately?

BACKGROUND

To prevent the development of bacterial resistance, current guidelines recommend vancomycin dosages of 15-20 mg/kg based on actual body weight.

OBJECTIVE

Our aim was to determine if two community teaching Emergency Departments followed the new recommendations for a weight-based dosing regimen for vancomycin.

METHODS

A retrospective cohort study was conducted on the prescribing habits of vancomycin in the Emergency Department. During a 6-month time period, 1,734 doses of vancomycin were dispensed and a subsequent random sample of 240 doses was reviewed. Data collection included age, gender, weight, creatinine clearance, vancomycin dose, and indication for vancomycin therapy. Mean values, standard deviations, and ranges were computed to illustrate current prescribing practices.

RESULTS

The mean vancomycin dose was 1,117 ± 325 mg. Based on actual body weight, the calculated mean dose was 14.6 ± 5.7 mg/kg. Only 19.6% (47 of 240) of all patients received an appropriate dose based on the recommended 15-20 mg/kg vancomycin dose.

CONCLUSIONS

Our Emergency Department is inappropriately dosing vancomycin in the majority of patients. Educating clinicians regarding appropriate vancomycin dosing is recommended to achieve compliance with the latest consensus guidelines.

Comparison of hydromorphone and meperidine for ureteral colic

OBJECTIVE

To compare the efficacies of meperidine and hydromorphone in the treatment for ureteral colic in the emergency department (ED).

METHODS

A prospective, double-blind, randomized clinical trial was conducted over six months at a tertiary referral center with 93,000 annual ED visits. Seventy-three patients completed the study. The patients received either 1 mg of hydromorphone or 50 mg of meperidine IV at t = 0. Pain intensity was determined using a 10-cm visual analog scale at t = 0, 15, 30, 60, and 120 minutes. A second dose of the study drug could be given between t = 15 and t = 120 minutes when the clinician believed the initial dose was ineffective. Patients requiring more than one additional dose of analgesia were treated as nonresponders and were removed from the study.

RESULTS

Thirty-six patients received hydromorphone and 37 received meperidine. The initial pain intensities (hydromorphone group = 8.4 +/- 1.5; meperidine group = 8.5 +/- 2.1), age distributions, sex distributions, and side effects of the two groups were comparable. Pain relief was better (p < 0.05) with hydromorphone at t = 15, 30, 60, and 120 minutes. The hydromorphone group required rescue analgesia less often (31% vs 68%, p < 0.01), had fewer IV pyelographies (IVPs) (28% vs 54%, p < 0.05), and had a lower proportion of hospital admissions (25% vs 49%, p = 0.08).

CONCLUSIONS

For the fixed doses used in this study, the adult ureteral colic patients receiving hydromorphone achieved more pain relief, required less rescue medication, underwent fewer IVPs, and avoided hospital admission more frequently than did those receiving meperidine.