- See:
-
Aminoglycocides
-
Gentamicin in Renal Failure
- Discussion:
- indicated for serious Gm Neg infections caused by suseptable
Pseudomonas, Proteus,
E. coli,
Klebsiella,
Enterobacter sp., Serratia, and Gm Neg Sepsis;
- as with all aminoglycocides, gentamicin binds to bacterial ribosomes and inhibits protein synthesis;
-
tobramycin is more active than gentamicin against
Pseudomonas, including gentamicin-resistant strains, and is usually indicated over gentamicin
for pseudomonas infections, in combination with an antipseudomonal penicillin (AMA, 1983).
- references:
-
Aminoglycoside therapy. Current use and future prospects.
- Dosage:
- base dosage on Renal function and serum; 3-5 mg/kg/day in 3 divided doses / 24-36 hrs, or 1.5mg/8hrs - Loading Dose 2mg/kg;
- usual dose for serious infections is 1 mg/kg q 8 hrs;
- dose for Life Threatening Infections: 1.7 mg/kg q 8hr (reduce ASAP)
- peak: 5-8 ug/ml; trough: 1-2 ug/ml;
- w/
osteomyelitis
Dose time p admin. Mean Ser conc (ug/ml) Mean Bone conc (ug/gm)
1.7 mg/kg/8hr IM 120-60 3.7-6.0 3.66
- references:
-
Gentamicin volume of distribution in critically ill septic patients.
-
Gentamicin dosage requirements: wide interpatient variations in 242 surgery patients with normal renal function.
-
Increased burn patient survival with individualized dosages of gentamicin.
-
Kinetic model for gentamicin dosing with the use of individual patient parameters.
-
Aminoglycoside pharmacokinetics: dosage requirements and nephrotoxicity in trauma patients.
-
Bactericidal activity of gentamicin against S. aureus. In vitro study questions value of prolonged high concentrations.
-
Gentamicin pharmacokinetics in 1,640 patients: method for control of serum concentrations.
-
peds: 7.5 mg/kg/day q8hr (levels: trough < 2, peak:4-8)
-
Gentamicin in neonates: the need for loading doses.
Role of Gentamicin in Bone Cement:
-
addition of antibiotics to bone cement:
-
osteomyelitis
- references:
-
Release of gentamicin from acrylic bone cement. Elution and diffusion studies.
-
Role of gentamicin-impregnated cement in total joint arthroplasty.
-
Prophylaxis with systemic antibiotics versus gentamicin bone cement in total hip arthroplasty. A five-year survey of 1688 hips.
- Misc:
- diffusion from Blood into CSF minimaleven w/Inflammation;
- note: ratio of CSF to blood level (%): normal meninges: nil; inflammed meninges: 10-30;
- dosing Regimens for Patients with Renal Insufficiency: (Dose for 70 kg Adult (gm/dosing interval in hours):
- CrCl: >80: = 0.10-0.14/8; CrCl: 50-79 = 0.10-0.14/12-18;;
- CrCl:30-49 = 0.10-0.14/12-18;; CrCl::10-29 = 0.10-0.14/24-36;;
- 70% of drug will be excreted in to urine (w/ nl RF(x))
-
Gentamicin in the Renal Failure Patient:
- Complications:
-
renal failure:
- note nephrotoxicity, ototoxicity, decrease dose with renal failure;
- parental
aminoglycosides: Will interact with cephalothin (nephrotoxicity), Cis platin (nephrotoxicity,ototoxicity)
- ether and neuromuscular blocking agents (apnea or respiratory paralysis), loop diuretics, (ototoxicity), Pen in RF
- decreased aminoglyc effectiveness)
vancomycin (nephrotoxicity), oral anticoagulants (Increase PT);
- references:
- Nephrotoxicity and ototoxicity of aztreonam versus aminoglycoside therapy in seriously ill nonneutropenic patients.
-
The absence of nephrotoxicity and differential nephrotoxicity between tobramycin and gentamicin.
