NURS 3550 Gentamycin exam with verified
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answers
Chapter |87 |presents |the |aminoglycosides, |antibiotics |that |inhibit |protein |synthesis. |The |chapter |
begins |with |the |basic |pharmacology |of |these |agents. |- |✔✔
Aminoglycosides |are |narrow-spectrum |antibiotics |used |primarily |against |- |✔✔aerobic |gram-negative |
bacilli.
Aminoglycosides |disrupt |- |✔✔protein |synthesis, |causing |rapid |bacterial |death.
The |aminoglycosides |can |cause |serious |injury |to |the |- |✔✔inner |ear |and |kidneys. |Because |of |these |
toxicities, |indications |for |these |drugs |are |limited.
Aminoglycosides |are |highly |- |✔✔polar |polycations. |As |a |result, |they |are |not |absorbed |from |the |
gastrointestinal |tract |and |therefore |must |be |administered |parenterally |to |treat |systemic |infections.
The |aminoglycosides |are |bactericidal. |Cell |kill |is |concentration |dependent. |Therefore, |the |higher |the |
concentration, |the |more |rapidly |an |infection |clears. |- |✔✔
Bactericidal |activity |persists |for |several |hours |after |serum |levels |have |- |✔✔dropped |below |the |
minimal |bactericidal |concentration; |this |phenomenon |is |known |as |the |postantibiotic |effect.
The |principal |cause |of |bacterial |resistance |is |the |production |of |- |✔✔enzymes |that |can |inactivate |
aminoglycosides. |Of |all |the |aminoglycosides, |amikacin |is |least |susceptible |to |inactivation |by |bacterial |
enzymes.
The |principal |use |for |parenteral |aminoglycosides |is |treatment |of |- |✔✔serious |infections |caused |by |
aerobic |gram-negative |bacilli.
, One |aminoglycoside—gentamicin—is |now |commonly |used |in |- |✔✔combination |with |either |
vancomycin |or |a |beta-lactam |antibiotic |to |treat |serious |infections |with |certain |gram-positive |cocci.
The |aminoglycosides |are |eliminated |primarily |by |- |✔✔the |kidneys. |Accordingly, |to |prevent |serious |
toxicity, |the |dosage |size |must |be |reduced |or |the |dosing |interval |must |be |increased |in |patients |with |
kidney |disease.
The |aminoglycosides |can |produce |- |✔✔serious |toxicity, |especially |to |the |inner |ear |and |kidneys. |These
|structures |are |vulnerable |because |aminoglycosides |become |concentrated |within |their |cells.
The |risk |of |ototoxicity |is |related |primarily |to |- |✔✔persistently |elevated |trough |drug |levels |rather |than
|to |excessive |peak |levels.
Patients |should |be |monitored |for |- |✔✔ototoxicity. |The |first |sign |of |impending |cochlear |damage |is |
high-pitched |tinnitus |(ringing |in |the |ears). |Ototoxicity |is |largely |irreversible. |Accordingly, |if |permanent |
injury |is |to |be |avoided, |aminoglycosides |should |be |withdrawn |at |the |first |sign |of |damage |(i.e., |
tinnitus, |persistent |headache, |or |both).
Aminoglycosides |can |injure |cells |of |the |- |✔✔proximal |renal |tubules.
Nephrotoxicity |correlates |with |- |✔✔(1) |the |total |cumulative |dose |of |aminoglycosides |and |(2) |high |
trough |levels.
Aminoglycoside-induced |nephrotoxicity |usually |manifests |as |- |✔✔acute |tubular |necrosis.
Injury |to |the |kidneys |usually |reverses |after |- |✔✔aminoglycoside |use |is |discontinued.
Aminoglycosides |can |inhibit |neuromuscular |transmission, |causing |- |✔✔flaccid |paralysis |and |
potentially |fatal |respiratory |depression. |Most |episodes |of |neuromuscular |blockade |have |occurred |
following |intraperitoneal |or |intrapleural |instillation |of |aminoglycosides. |However, |neuromuscular |
blockade |has |also |occurred |with |IV, |IM, |and |oral |dosing.
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answers
Chapter |87 |presents |the |aminoglycosides, |antibiotics |that |inhibit |protein |synthesis. |The |chapter |
begins |with |the |basic |pharmacology |of |these |agents. |- |✔✔
Aminoglycosides |are |narrow-spectrum |antibiotics |used |primarily |against |- |✔✔aerobic |gram-negative |
bacilli.
Aminoglycosides |disrupt |- |✔✔protein |synthesis, |causing |rapid |bacterial |death.
The |aminoglycosides |can |cause |serious |injury |to |the |- |✔✔inner |ear |and |kidneys. |Because |of |these |
toxicities, |indications |for |these |drugs |are |limited.
Aminoglycosides |are |highly |- |✔✔polar |polycations. |As |a |result, |they |are |not |absorbed |from |the |
gastrointestinal |tract |and |therefore |must |be |administered |parenterally |to |treat |systemic |infections.
The |aminoglycosides |are |bactericidal. |Cell |kill |is |concentration |dependent. |Therefore, |the |higher |the |
concentration, |the |more |rapidly |an |infection |clears. |- |✔✔
Bactericidal |activity |persists |for |several |hours |after |serum |levels |have |- |✔✔dropped |below |the |
minimal |bactericidal |concentration; |this |phenomenon |is |known |as |the |postantibiotic |effect.
The |principal |cause |of |bacterial |resistance |is |the |production |of |- |✔✔enzymes |that |can |inactivate |
aminoglycosides. |Of |all |the |aminoglycosides, |amikacin |is |least |susceptible |to |inactivation |by |bacterial |
enzymes.
The |principal |use |for |parenteral |aminoglycosides |is |treatment |of |- |✔✔serious |infections |caused |by |
aerobic |gram-negative |bacilli.
, One |aminoglycoside—gentamicin—is |now |commonly |used |in |- |✔✔combination |with |either |
vancomycin |or |a |beta-lactam |antibiotic |to |treat |serious |infections |with |certain |gram-positive |cocci.
The |aminoglycosides |are |eliminated |primarily |by |- |✔✔the |kidneys. |Accordingly, |to |prevent |serious |
toxicity, |the |dosage |size |must |be |reduced |or |the |dosing |interval |must |be |increased |in |patients |with |
kidney |disease.
The |aminoglycosides |can |produce |- |✔✔serious |toxicity, |especially |to |the |inner |ear |and |kidneys. |These
|structures |are |vulnerable |because |aminoglycosides |become |concentrated |within |their |cells.
The |risk |of |ototoxicity |is |related |primarily |to |- |✔✔persistently |elevated |trough |drug |levels |rather |than
|to |excessive |peak |levels.
Patients |should |be |monitored |for |- |✔✔ototoxicity. |The |first |sign |of |impending |cochlear |damage |is |
high-pitched |tinnitus |(ringing |in |the |ears). |Ototoxicity |is |largely |irreversible. |Accordingly, |if |permanent |
injury |is |to |be |avoided, |aminoglycosides |should |be |withdrawn |at |the |first |sign |of |damage |(i.e., |
tinnitus, |persistent |headache, |or |both).
Aminoglycosides |can |injure |cells |of |the |- |✔✔proximal |renal |tubules.
Nephrotoxicity |correlates |with |- |✔✔(1) |the |total |cumulative |dose |of |aminoglycosides |and |(2) |high |
trough |levels.
Aminoglycoside-induced |nephrotoxicity |usually |manifests |as |- |✔✔acute |tubular |necrosis.
Injury |to |the |kidneys |usually |reverses |after |- |✔✔aminoglycoside |use |is |discontinued.
Aminoglycosides |can |inhibit |neuromuscular |transmission, |causing |- |✔✔flaccid |paralysis |and |
potentially |fatal |respiratory |depression. |Most |episodes |of |neuromuscular |blockade |have |occurred |
following |intraperitoneal |or |intrapleural |instillation |of |aminoglycosides. |However, |neuromuscular |
blockade |has |also |occurred |with |IV, |IM, |and |oral |dosing.
