Anti-Infective Agents - Macomb

Download Report

Transcript Anti-Infective Agents - Macomb

Anti-Infective Agents
Cholinergics
Surface Tension Reducing Agents
Nicotine Replacement Therapy
Module G
Topics for Discussion
• Anti-infective agents
•
•
•
•
•
Antibacterial
Antitubercular
Antiviral
Antifungal
Antiprotozoal
• Parasympathomimetics (cholinergics)
• Surfactant Agents
• Nicotine Replacement Therapy
Terminology
•
•
•
•
•
•
Antibiotic: Substance that kills microorganism
growth.
Pathogen: Disease causing microorganism.
Empiric: Therapy that is started based upon on
experience and precedent in the observation
and treatment of disease.
Normal flora: Organisms found in various parts
of the body living symbiotically.
Aerobic: Requires oxygen to survive.
Anaerobic: Does not require oxygen to survive.
Terminology
•
•
•
•
•
Gram Stain: Laboratory test used to determine
if an organism is gram-positive or gramnegative.
C & S: Culture and sensitivity. Determines the
organism present in the culture and the
antibiotic to which it is sensitive (susceptible to).
Bacteriostatic: Inhibits replication of
microorganisms and prevents growth. Does
not kill bacteria.
Bacteriocidal: Kills the bacteria.
Broad spectrum vs. Narrow spectrum
Classes of Anti-infective Agents
Classes of Antibiotics
Antibiotics
• Beta Lactams
• penicillins
• cephalosporins (4 generations)
• Broader coverage with each generation.
• Aminoglycosides
• tobramycin
• Vancomycin
• MRSA
• Protein Synthesis Inhibitors
• macrolides
• tetracyclines
• Folate Inhibitors
• metronidazole
tobramycin
• Antibiotic used to treat pneumonias associated
with cystic fibrosis (p. 286).
• Pseudomonas aeruginosa
• Trade Name is Tobi
• Dosage:
• 300 mg/5 mL unit dose vial
• Give one vial BID
• 28 days on, 28 days off
• Very viscous solution
• Administer a bronchodilator prior to giving Tobi.
• Bronchospasm common side-effect.
Pari LC Plus Nebulizer
•Tobi needs to
be delivered
with Pari LC
Plus nebulizer
•Flowrates
should be set
at 10 – 12
L/min
colistimethate
• Brand Name: Colymycin, Colistin
• Alterative to Tobi in drug-resistant strains of
Pseudomonas.
• From a group of antibiotics known as polymyxins
and is similar to polymyxin B.
• Supplied as a powder that needs to be
reconstituted.
• Has been identified to produce bronchospasm in
some patients.
• May require pre-treatment with a bronchodilator.
• Dose:
• Children less than 2 years of age: 1 MU twice daily.
• Children older than 2 years of age & adults: 2 MU
twice daily
Antibiotics and Pneumonias
Page 281
Anti-Viral Agents
• A virus is an obligate parasite.
• Kill the organism, risk killing the host.
• RNA Viruses
•
•
•
•
•
Influenza
Polio
HIV
Rabies
Encephalitis
• DNA
•
•
•
•
Adenovirus Respiratory Disease
Papilloma warts
Herpes Simplex
Epstein-Barr Mononucleosis
Anti-Viral Agents
• Anti-Prototozoal Agents
• pentamidine
• Used to treat Pneumocystis carinii pneumonia
(PCP) – Organism may be a virus, may be a
protozoa.
• Anti-viral Agents
• ribavirin
• Used to treat Respiratory Syncytial Virus
ribavirin
• Trade Name: Virazole
• Antiviral Drug given with SPAG nebulizer
• Used to treat Respiratory Syncytial Virus
(RSV), influenza A and B and herpes
simplex
• Bronchiolitis and pneumonia.
• RSV virus affects all children by age 3.
• Use of ribavirin has decreased dramatically
over the past 5 years.
Environmental Exposure
• In animal studies, ribavirin has been found
to be
•
•
•
•
Mutagenic
Carcinogenic
Teratogenic
Embryocidal
• Pregnant women or women thinking of
becoming pregnant should avoid exposure
ribavirin
• American Academy of Pediatrics
recommends ribavirin to ONLY be given for
children with RSV and:
• Congenital Heart Disease
• Bronchopulmonary Dysplasia
• Immunodeficient patients (cancers, AIDS,
malnutrition)
• Infants requiring mechanical ventilation
• Premature infants or infants less than 6 weeks
RESPIRATORY SYNCYTIAL VIRUS
IMMUNE GLOBULIN
INTRAVENOUS – RSV-IGIV (1996)
•
•
Trade Name: RespiGam
Indications
•
•
•
Indicated for the prevention of serious
lower respiratory tract infection with
RSV in children under 24 months of
age.
RSV-IGIV is a sterile liquid formulation
of immunoglobulin G (IgG) containing
antibody to RSV
Administration is by IV
RSV Virus
• Supportive Care
• Hydration
• Oxygen
• Bronchodilators
• Most Commonly seen in Winter Months
• November – March
• Handwashing is the most effective way to
interrupt the spread of RSV
Anti-Fungal Infections
• Fungi include mushrooms, yeasts & molds.
• Fungal infections occur in immunocompromised
patients.
• Common examples include athlete's foot, ringworm.
• Histoplasmosis capsulatum, Aspergillosis,
Blastomycosis, & Candida albicans (oral thrush).
• Key agents
• amphotericin B
• nystatin
• IV administration. Given experimentally by
aerosol.
• No approval from FDA
NON-AEROSOLIZED ANTI-INFECTIVE
DRUGS ANTI-TUBERCULOSIS
AGENTS
•
•
The standard approach to treating
tuberculosis (TB) today consists of multiple
first line drugs for a period of either 6 or 9
months.
First line drugs are:
•
•
•
•
•
Rifapentine
Isoniazid
Rifampin
Ethambutol
Pyrazinamide
•
Streptomycin used to be a front-line drug, but has been
replaced by Rifapentine.
NON-AEROSOLIZED ANTI-INFECTIVE
DRUGS ANTI-TUBERCULOSIS
AGENTS
•
9 Month approach
•
•
6 Month approach
•
•
•
Isoniazid and Rifampin are given for 9 months and in an initial
2 to 8 week period these two drugs are supplemented with
one of the other first line drugs.
Four drugs are used for 2 months followed by 4 months of
Isoniazid and Rifampin.
There is an association of TB and HIV infection.
Along with the disturbing increase in the number of TB
cases in conjunction with AIDS, there has been an
emergence of drug resistant strains of TB. The
cure rate is poor in this subset.
lidocaine
• Trade Name: Xylocaine
• Effect: Anesthetic
• Indications
• Aerosolized prior to bronchoscopy
• Topically as nasal spray/jelly prior to
intubations
• Anesthetize area prior to chest tube insertion,
(thoracentesis)
lidocaine
• Dosage for nebulization – Use SVN
• 2% solution; 20 mg/mL; 3-7 mL total volume
• 4% solution; 40 mg/mL; 3-7 mL total volume
• Nasal Spray
• 2% solution
• Jelly for lubricating ET tubes
• 2%
Nicotine Replacement Therapy
• What:
• Nicotine Replacement Therapy should be used as part
of a comprehensive smoking cessation program.
• Why:
• Smoking kills 440,000 Americans each year and
debilitates ½ of all long-term smokers.
• Tobacco dependence is a powerful addiction.
• Tobacco relapses are high (5 attempts?).
• Who:
• Fagerstrom Test for Nicotine Dependence.
• Figure 13-4, Page 256
• When:
• Best time is when they are in the hospital.
Nicotine Replacement
Therapy
• Nicotine Transdermal System
•
•
•
•
Habitrol
Nicoderm
Nicotrol
ProStep
• Nicotine Gum
• Nicorette
• Nicotine Nasal Spray
• Nicotrol
• Other (Non-NRT)
• bupropion (Zyban, Wellbutrin)
• Vareniciline (Chantix)
Nicotine Replacement
Therapy
• Nicotine stimulates the cholinergic receptor
site
• Nicotinic Receptor Sites
• Autonomic and Somatic Nervous System
• Involuntary and voluntary skeletal muscle systems
• Nicotine directly affects brain cells
• Increases alertness
• Euphoria
• Cognitive performance
Other Agents
• bupropion (Zyban, Wellbutrin)
• Antidepressant usually used to treat major depressive
disorders and season affective disorders.
• Also decreases urge to smoke; mechanism is unclear.
• vareniciline (Chantix)
• Mechanism of action is to partially block the a4-b2
nicotinic receptor in the brain.
• Within 10 to 20 seconds of a single puff from a
cigarette, nicotine attaches to this receptor.
• The receptor, in turn, triggers large increases in
dopamine, which rewards the smoker with a
pleasurable sensation.
Nicotine Replacement Therapy
• Precautions/Instructions
• Replacement formulas DO contain nicotine.
• Side effects can occur if using replacement formulas
with tobacco.
• Transference of nicotine dependency can occur.
• Replacement formulas should be gradually withdrawn
and stopped within 3 months.
• HCW should avoid handling nicotine products.
• varenicline and bupropion: Mood swings even
after drug has been stopped; some instances of
suicide ideation have been associated with
Chantix.
• Questionable whether Chantix had direct influence or
not.
methacholine
• Trade Name: Provocholine
• Used in Pulmonary Function Lab
• Methacholine Challenge Test
• Bronchoprovocation Test
• Used to test for hypersensitive airways
• Parasympathomimetic
• Induces bronchospasm
methacholine Challenge Test
• Used for patients with normal pulmonary
functions
• Chronic cough
• Recurrent respiratory infections
• History of wheezing
• Have crash cart in the room
• Be prepared to administer a fast acting
bronchodilator (metaproterenol)
Surfactant Agents
• Ethyl Alcohol
• Used in the treatment of pulmonary edema
• Alcohol breaks the bubbles and decreases the
surface tension of the exudate
• Lack of approved clinical use
• Efficacy is not well established
• Dosage: 30 – 50% 3-5 mL of a 40%
solution by aerosol or direct instillation
down ET tube
Exogenous Surfactants
• Natural Surfactants
• Surfactants from natural sources with addition
or removal of certain molecules
• Survanta, Calfactant, Poractant Alfa
• Artificial Surfactants
• Surfaxin (?)
• Synthetic Natural – genetic engineering;
cloning gene of natural surfactant
• None present
Beractant
• Trade Name: Survanta (1991)
• Mixture of bovine (cow) lung extract to
which DPPC (lecithin) has been added
• Watch ventilator settings after
administration
• O2 can increase, over-ventilation, hypocarbia
• Administered down ET tube
New Surfactants
• Calfactant (Infasurf)
• Bovine Extract
• Poractant Alfa (Curosurf)
• Porcine Extract