Term
Beta-lactam Antibacterials |
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Definition
•Derive name from beta-lactam ring, which is part of their chemical structure
–Ring is essential for antibacterial activity
–Specific enzymes can disrupt ring
•Inactivate mechanism of action
•Major mechanism of action in acquiring resistance
•Characteristics widely differ
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Term
Beta-lactam Antibacterials |
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Definition
–Penicillins
–Cephalosporins
–Carbapenems
–Monobactams
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Term
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Definition
•Safe, effective, widely used ATB
•First ATB developed
–Had to be given parenterally
•Destroyed by gastric acid
•Injections were painful
–Extensive use produced drug-resistant strains of staphylococci
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Term
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Definition
•Post-absorption
–Widely distributed
–Achieve therapeutic concentrations in most body fluids
•Not usually obtained in intraocular and CSF unless inflammation present
–Rapidly excreted by kidneys
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Term
Penicillins
Indications for use
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Definition
–Bacterial infections caused by susceptible organisms
–More effective in gram(+) than gram(–) infections
–Skin/soft tissue, respiratory, GI and GU infections
–Incidents of resistance continue to increase
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Term
Penicillins
Contraindications for use
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Definition
–Hypersensitivity/allergic reaction to any penicillin preparation
–Potential exists for cross-allergenicity with cephalosporins and carbapenems
•In life-threatening allergic reactions to PCN, cephalosporin and carbapenem use is to be avoided
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Term
Extended-spectrum Penicillins |
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Definition
•Broad-spectrum ATB
–Especially against gram(-) organisms
•Available orally for UTIs, prostatitis
•Intermittent IV dosing
•Most can be given IM
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Term
Penicillin/Beta-lactamase Inhibitor Combinations |
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Definition
•Beta-lactamase inhibitors
–Very little antibacterial activity
–Bind with and inactivate beta-lactamase
•Protects PCN from destruction
•Extends PCN’s spectrum of efficacy
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Term
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Definition
•Widely used group of medications
–Derived from a fungus
•Broad-spectrum ATB with activity against gram(+) and gram(-) bacteria
–More active against gram(-) compared with PCNs
•Widely distributed into most body fluids and tissues
–Maximum concentration in liver and kidneys
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Term
Cephalosporins
Clinical indications for use
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Definition
–Surgical prophylaxis
–Treatment of infections
•Respiratory tract, urinary tract
•Skin, soft tissues
•Bones, joints
•Brain, spinal cord; septicemia
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Term
Cephalosporins
Contraindications for use
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Definition
–Previous anaphylactic reaction to PCN
•Cross-sensitivity low in those with delayed reactions to PCN
•Skin rash
–Cephalosporin allergy
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Term
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Definition
•Broad-spectrum, bactericidal beta-lactam antimicrobials
•Inhibit synthesis of bacterial cells walls by binding with penicillin-binding proteins
•Three medications
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Term
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Definition
•Active against gram(-) bacteria
•Active against many strains that are ATB resistant
•Does not cause kidney damage or hearing loss (as can aminoglycosides)
•Indications for use
–Urinary tract, skin/skin structures, lower respiratory tract, intra-abdominal and gynecologic infections, septicemia
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Term
Is the following statement True or False?
The classification of beta-lactam antibiotics refers to cephalosporins, carbapenems, and monobactams.
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Definition
False.
The classification of beta-lactam antibiotics refers to penicillins, cephalosporins, carbapenems, and monobactams.
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Term
Beta-lactam Antibacterials
Mechanism of action
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Definition
–Inhibits synthesis of bacterial cell wall
•Binding with proteins
•Produces defective cell wall, which destroys microorganism
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Term
Is the following statement True or False?
The mechanism of action for beta-lactam antibiotics is to prevent the duplication of bacterial cells.
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Definition
False.
The mechanism of action for beta-lactam antibiotics is to produce a defective cell wall, which results in the destruction of the microorganism.
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Term
Principles of Antimicrobial Therapy
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Definition
–Prevent/treat infections caused by pathogenic organisms
•Drug selection
–Depends on organism causing infection
–Severity of infection
–Other factors
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Term
Use in Special Populations |
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Definition
•Perioperative use
•Children
•Older adults
•Renal impairment
•Hepatic impairment
•Clients with critical illness
•Home care
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Term
Perioperative use of cephalosporins: |
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Definition
Are used insurgical prophylaxis
1st generation is use for gram + is cefazolin
2nd cefotetan & cefoxitin are used abdominal, gynecologic & colorectal sirgery against gram - |
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Term
| Cephalosporins should be use |
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Definition
| Within 2 hours before 1st skin incision is made so the drug has time to reach therapeutic serum. |
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Term
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Definition
| Penicillins and cephalosporins are widley use to treat infection in children and generally safe |
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Term
| Use in Children of penicillins & cephalosporin |
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Definition
| Dosage shoul be based on age, weight severity of the infection beging treated, & renal function |
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Term
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Definition
| Beta-lactam antibacterials are relativelt safe, although decrease renal function, other disease process, and concurrent drug therapies increase the risks of adverse effectes in older adults. |
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Term
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Definition
| With penicillins, hyperkalemia may occur with large IV dose of penicillin G potassium and hypernatremia may occur with ticarcillin. |
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Term
| Risk In Used Older Adults |
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Definition
| Cephalosporins may aggravate renal impairment, especially when other nephrotoxic drugs are used concurrently |
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Term
| Other Risk in Older Adults |
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Definition
| Dosage of most cephalosporins must be reduced in the presence of renal impairment, depending on creatinie clearance |
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Term
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Definition
| Beta-lactam antimicrobials are excreted mainly by the kidneys and may accumulate in the presence of renal impairment |
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Term
Use in Renal impairment Penicillin |
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Definition
- Dosage is reduce of Penicillin
- Patients on hemodialysis usually require an additional dose after treatment because hemodialysis removes
- Carbenicillin dose not reach therapeutic
- Nephropathy High dosage can contribute to hypersensitiy reaction
- Electrolyte imbalances
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Term
USE in Renal impairment Cephalosporins |
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Definition
Reduce dosage because usual dosage may produce high and prolonged serum drug levels.In renal failure dosage of all cephalosporins should be reduce
Cefotaxime can cause toxicity in patients with renal impairment |
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Term
| USE in Renal impairment Carbapenems |
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Definition
- Drug is contraindicated in renal impairment & should be reduce
- Dosage of meropenem should be reduced with renal impairment
- Dosage of ertapenem should be reduced to 500 miligrams daily
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Term
| USE in Renal impairment Monobactum |
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Definition
- Aztreonam should be reduced by 50% or more in patients with CrCl of 30 ml
- Life threating infection in clients give 12.5%
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Term
Use in Patients with Hepatic impairment |
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Definition
- A few beta-lactam antibiotics may cause or aggravate hepatic impairment
- Amoxicillin-clavulante should be used with caution in patients with hepatic impairmen
- Aztreonam,imipenem, meropenem, and ertapenem may cause abnormalities in liver function
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Term
Clients with critical illness |
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Definition
| The beta-lactam grugs are frequently given concomitantly with other antimicrobialdrugs because critically ill patients often have multiorganism or nosocomial infections |
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Term
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Definition
| The antibiotics are given oral in home setting. Liquid suspensions for childern should be measure with a spoon or medication device |
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