Gentamicin Regimen
From WardWiki - Foundation Doctor Helper
Contents |
Make sure patient is suitable
Calculate the creatinine clearance.
Do NOT use this regimen for:
- Pregnant women
- Children < 16 years
- Urology surgery prophylaxis
- Any patients with
- Ascites
- A limb amputation
- Cystic fibrosis
- Endocarditis
- Major burns
- Renal transplant
- Renal impairment – creatinine clearance <30mL/min DO NOT USE eGFR
Dose calculation
- Determine patients
- sex
- height
- weight in kg
Use local guidelines or BNF for dosing the gentamicin.
Administration
Dilute the gentamicin dose in 100mL sodium chloride 0.9% and give by intravenous infusion over 1 hour. Record on the drug chart the exact start time of the infusion.
How to measure gentamicin levels
Most laboratories are able to do assays daily but not out of hours. Take a blood sample at the right time and the sample will be analysed in hours and the result should be available before the next dose is due. Do not take the blood sample from the IV line used for gentamicin administration. Take one blood sample (ideally 10mL) between 6 and 14 hours after the start of the first infusion. Document on the microbiology request form the EXACT time and date the infusion was set up and the EXACT time and date the sample was taken in addition to the patient details.
Selecting dose interval
Plot the level on the nomogram. If the level falls in the area designated 24hours, 36hours or 48hours the dosing interval is 24, 36 or 48 hourly respectively. If the level falls on a line between dosing intervals choose the longer interval. If the level is above the 48 hour line STOP the treatment. If the gentamicin is to be continued take daily levels but do not give any more gentamicin until the level falls below 2mg/L.
Repeated monitoring
U&Es and creatinine need to be checked daily in all patients on the Hartford Gentamicin Regimen. Repeat gentamicin levels as shown in the table. If the serum creatinine is rising significantly (20% or more), and it is still within 6-14 hours of the start of this gentamicin infusion measure the gentamicin level as soon as possible. If more than 14 hours contact microbiology or pharmacy for advice.
| Dosage interval | Repeat level |
|---|---|
| 24 hours | 3 days |
| 36 hours | 3 days |
| 48 hours | 2 days |
