256 short answers Flashcards
Positive inotropic effect
Increased contraction – Digoxin
Negative Inotropic effect
– Decreased contraction – propranolol
Positive Chronotropic effect
accelerates the HR – Adrenaline
Negative chronotropic effect
Has the opposite effect and decreases the HR eg digoxin
Positive dromotropic effect
– Increases conduction eg phenytoin
Negative dromotropic effect
– Delays conduction eg verapamil
Why are antiretroviral drugs often used in combination for the treatment of HIV?
Are effective on susceptible cells (but ineffective in cells already infected with HIV) –reduces the speed of disease progression
As a nurse who may be administering cytotoxic agents to patients within various healthcare settings, an understanding of how to handle these medications appropriately is essential. Cytotoxic drugs are inherently toxic and many can be absorbed through the skin during handling. List some of the precautions that maybe necessary when handling this type of medication.
- Prepared & dispensed in cytotoxic drug safety cabinet
- Use correct PPE
- Excess drug, waste and equipment are disposed of at high temperatures
- Regular bloods for staff : liver & kidney function tests
- Label and carefully monitor all equipment and drugs
- Follow facilities guidelines
Breast and Prostate cancer are common examples of hormone dependent cancers. Discuss the possible treatment options available using either breast or prostate cancer as an example.
- Surgery
- Radio therapy and chemotherapy
- Hormone replacement – anti oestrogens (letrozole)
A growing problem in the health care industry in antimicrobial resistance, Discuss three distinct mechanisms by which bacteria can develop drug resistance.
- The target site of the drug is altered so the drug cannot bind to the target
- The microorganism produces an enzyme that modifies or destroys the structure of antibiotic and renders it inactive
- Antimicrobial drug is unable to reach the target site
Antibiotics generally fall into four distinct groups defined by their mechanisms of action or how they exert their bactericidal or bacteriostatic effect. Discuss how the following classes of antibiotics exert their effects and give examples from each class.
Inhibitors of Bacterial Cell Wall Synthesis
- Penicillins – Amoxicillin, effective against gram positive and are derived from common moulds (bread & fruit), constitute a large group of antimicrobial agents that are the most effective and least toxic of all available antimicrobial drugs.
- Cephalosporins – Cepalexin, inhibits bacterial cell wall synthesis and are bactericidal. Rapidly dividing bacteria are affected the most.
- Carbapenems - Ertapenem, inhibit cell wall synthesis, kills sensitive bacteria, and binds to penicillin binding proteins.
- Glycopeptides – Vancomycin, are complex antibiotics, inhibit cell wall synthesis and are active against gram positive bacteria.
Antibiotics generally fall into four distinct groups defined by their mechanisms of action or how they exert their bactericidal or bacteriostatic effect. Discuss how the following classes of antibiotics exert their effects and give examples from each class.
Bacterial Protein Synthesis Inhibitors
- Macrolide Antibiotics – Erythromycin, Bacteriostatic, inhibit growth of microorganisms in high concentrations.
- Lincosamides – Lincomycin & Clindamycin, used to treat serious streptococcal and staphylococcal infections. Clindamycin is preferred – better oral absorption and more potent than lincomycin.
- Aminoglycosides – Gentamycin, potent bactericidal antibiotics usually reserved for serious life-threatening infections. Very effective against gram negative but limited against gram positive.
- Tetracyclines – Doxycycline, minocycline & tetracycline, bacteriostatic for many gram neg and pos organisms. Used to treat acne vulgaris, UTIs, bronchitis and numerous other systemic bacterial infections.
Explain why the plasma drug concentration of the aminoglycoside gentamicin is monitored
- To ensure that therapeutic concentrations are achieved without the risk of adverse reactions due to high plasma concentrations
- Monitored due to the occurrence of renal failure
- Plasma concentrations and renal function determine the dose
Pain is largely a subjective experience for the patient; however as health professionals we classify pain according to its time course or its origin. Define the following as they relate to pain;
- Acute Pain – sudden onset, obvious cause usually related to injury, surgery or disease and lasts a short time
- Chronic Pain - persistent or reoccurring, continues for more than 3 months, may be difficult to relieve with simple pain treatment
- Nociceptive Pain – physiological pain, tissue injury or inflammation
- Neuropathic Pain – nerve pain, from a primary lesion or dysfunction in the somatosensory nervous system pathways i.e. nerve compression due to prolapsed disc, inflammation, trauma like a limb amputation
- Psychogenic Pain – has psychological, psychiatric or psychosocial causes i.e. depression, anxiety and fear of dying has been known to cause severe drug. Drug therapy alone does not bring relief, need a multimodal approach
Opioid receptors are found in both the central and peripheral tissues. List three central effects and three peripheral effects of opioids
Central effects:
- Analgesia
- Suppress cough
- Euphoria
Peripheral effects:
- Constipation
- Urinary retention
- Suppression of some spinal reflexes
Describe the action taken following an opioid overdose including the use of opioid antagonists.
- Naloxone is an opioid antagonist
- Timely administration is vital
- Important to check level of consciousness, pupil response and for respiratory depression
Paracetamol is normal doses is considered to be a safer over the counter analgesic than aspirin. List the reasons why
- Adverse effects and allergic reactions are rare with therapeutic doses
- Aspirin is harder on the GI tract
- Lower risk of gastric upset, peptic ulcers or bleeding, tinnitus or renal impairment compared with aspirin or other NSAIDS
- Aspirin can mix badly with other medications
- Paracetamol has fewer side effects
- Is safe to use during pregnancy and lactation
- Can be given to children to reduce fever and cold and flu symptoms
There are four characteristics of inflammation name them and outline the three basic events that account for these characteristics
- Swelling due to distention of tissue…
- Which compresses nerves and causes pain
- Inflammation involves fluid movement, when blood vessels dilated upstream of an infection this will result in redness…
- And heat
Non-Steroidal Anti-inflammatory Drugs (NSAIDs) are one of the most commonly administered drug groups worldwide. Discuss the reasons why NSAIDs cause gastric ulceration and nephrotoxicity.
• They inhibit cyclooxygenase
• Acid molecules irritate gastric mucosa reducing levels of prostaglandin
- impair barrier properties of the mucosa
- cause fluid retention, electrolyte disturbances, decrease GFR
Natural Immunity
– the body has certain inherited and innate abilities to resist antigens i.e. rest, nutrition, exercise and freedom from undue stress
Acquired Immunity
– antibodies activate cellular defences and engulf antigens. They remember previous encounters and evolve
Passive Immunity
– antibodies made by the mothers body are transferred by the placenta or breast milk (especially colostrum) to the foetus or infant
Artificially Acquired Active Immunity
initiated purposefully for the protection of an individual by deliberately administering antigens i.e. vaccine
Artificially Acquired Passive Immunity
often chosen for susceptible individuals after a known exposure
