Pharmacology Lecture #2

1. Pharmacology Lecture #2

2. Care and Handling of Medications and Solutions • Medication Identification: • Medications come in a variety of packaging • Glass, Metal, and Plastic • Common Types of Containers in the OR: Ampule Tubes Vial Paper Preloaded syringe Foils/plastic • Glass breaks and is considered a sharp for disposal purposes

3. Name (trade & generic) Manufacturer Strength Amount Expiration Route Lot number Handling/Storage directions Classification (if controlled substance) Read Medication Labels and Check

4. Identification • Name, strength, amount, and expiration should be checked three times before use 1. When obtained 2. Prior to preparation or delivery to sterile field 3. After on the sterile field and prepared for use will be labeled by the surgical technologist

5. Labeling Medications • Medications are labeled according to institutional policy • Some labels come prepared sterile • Blank labels are included in sterile packs and can be written on with a sterile marker • Steri-strips can be used as labels when none are available and written on with a sterile marker • Syringes and med cups should be labeled

6. The Six Rights • Right Patient • Right Drug • Right Dosage/Amount • Right Route • Right Time and Frequency • Right Labeling/Documentation (new as of 2007) • It is the responsibility of the circulator and surgical technologist to verify this information

7. MEDICATIONS • Antibiotics • Ophthalmic agents • Diagnostic Agents • Local Anesthetics • Diuretics • Drugs Affecting Coagulation

8. Antimicrobials and Their Action • Inhibit synthesis of cell wall • Interfere with synthesis of protein • Alter the function of cell walls • Prevent RNA or DNA production (cell replication) • Interfere with metabolism of cells

10. Medications Used in Surgery • Antibiotics • Are given pre-operatively, intra-operatively, and post-operatively for prevention of bacterial infection. They can be administered intravenously, intra-muscularly, orally, topically as an ointment, and in an irrigation form • In the OR the ST will handle antibiotics that will be mixed with normal saline for irrigation purposes

11. Antibiotics • Their action may be bacteriostatic (inhibitive of bacterial growth) or bactericidal (bacteria killing) • Are a type of antimicrobial

12. Types of Antibiotics • Aminoglycosides • Cephalosporin's • Macrolids • Penicillin's • Tetracycline's • Each type has a variety of antibiotics in that category

13. Aminoglycosides • A group of antibiotics (such as gentamicin, polymyxin) that inhibit bacterial protein synthesis and are particularly active against Gram-negative bacteria. • Often used in eye cases.

14. Cephalosporin's • one of several broad spectrum antibiotic substances obtained from fungi and related to penicillin (trade names Mefoxin and Keflex). • prescribed for bacterial infections of the respiratory tract, the middle ear, the bones, the skin, and the reproductive and urinary systems.

15. Macrolids • A group of antibiotics produced by various strains of Streptomyces. • eg, clarithromycin, azithromycin used to treat infections such as respiratory tract and soft tissue infections.

16. Penicillin's • obtained from Penicillium molds • Penicillin acts by destroying the cell wall of bacteria. • may be used to treat infections such as urinary tract infections, septicemia, meningitis, intra-abdominal infection, gonorrhea, syphilis, pneumonia, respiratory infections, ear, nose and throat infections, skin and soft tissue infections.

17. Tetracycline's • derived from microorganisms of the genus Streptomyces and used broadly to treat infections. • A "broad-spectrum" antibiotic, is used to treat bacterial infections such as Rocky Mountain spotted fever, typhus fever, and tick fevers; upper respiratory infections; pneumonia; gonorrhea; amoebic infections; and urinary tract infections. • It is also used to help treat severe acne and to treat trachoma (a chronic eye infection) and conjunctivitis (pinkeye). • Tetracycline is often an alternative drug for people who are allergic to penicillin.

18. Ophthalmic Agents • Are multiple eye medications most given topically • ST must know what each agent does to know in what order to pass it to the surgeon • Eye Anatomy: • Conjunctiva • Anterior chamber (aqueous humor) • Iris/ciliary muscle • Posterior chamber (aqueous humor) • Pupil • Lens • Vitreous body (vitreous humor) • Retina (rods & cones) • Optic nerve

19. Eye Anatomy cont.

20. Types of Ophthalmic Agents • Enzymes • Irrigating • Viscoelastic • Miotics • Mydriatics • Ointments & Lubricants • Anti-inflammatories • Dyes • Anesthetics

21. Enzyme Agents • Speed up chemical reactions when mixed with anesthetic agents • Wydase (Hyaluronidase)

22. Irrigating Agents • Corneal moisture and operative site cleansing • BSS - Balanced salt solution – most common in our area • A-K Rinse • Blinx • Irigate • ST may need to irrigate as surgeon performs eye procedures

23. Viscoelastic Agents • Thick, jelly-like substance injected into anterior chamber to maintain expansion of the chamber and prevent injury to surrounding structures and tissue • May be used as vitreous substitute as well • Healon and Viscoat (Sodium Hyaluronate) • Occucoat (hydroxypropyl mthylcellulose)

24. Miotic Agents • Constrict the pupil • Post-cataract extraction to maintain implanted lens position • Laser iridectomy • Pilocarpine

25. Mydriatic Agents • Paralytic agents used to dilate the pupil • Atropine • Neo-Synephrine

26. Ointments & Lubricants • Prevent damage to the cornea from drying during general anesthesia • Lacrilube or Duratears • Prevent eye infections post-ophthalmic surgery • Erythromycin, Neosporin, Tobramycin, Gentamycin • Combination antibiotic/anti-inflammatory • Maxitrol and Tobradex

27. Anti-inflammatory Agents • Steroids • Suppress inflammatory response from traumatic eye injury • NSAIDs • Decrease or minimize post-operative inflammation

28. Dyes • Color or mark eye tissue • Help locate abnormalities or foreign bodies • Abnormal eye cells take up staining agents • Rose bengal (commonly used in eye drops to stain damaged conjunctival and corneal cells and thereby identify damage to the eye.) • Fluorescein sodium (Ful-Glo) (chemical dye used to identify and locate damage to the surface of the eye; useful in the management of diabetic retinopathy and macular degeneration)

29. Anesthetic Agents • Topical anesthesia for short ophthalmic surgical procedures • Tetracaine (Pontacaine) and Proparacaine OR • Lengthy ophthalmic procedures get a “retrobulbar” block (sensory and motor block) • Lidocaine or Bupivicaine (Marcaine) • May mix with Wydase to prolong effect or Epinephrine to vasoconstrict tissue to prolong anesthetic effect

30. Diagnostic Agents Includes: • Contrast media • Dyes • Staining Agents

31. Contrast Media • Used in radiographic diagnostic tests to enhance visualization • Most contain iodine, a radiopaque compound • Being radiopaque it illuminates tumors, stones, blockages, veins, and arteries (where ever it is injected) • Types include: Omnipaque & Hypaque • Often incorrectly referred to as dyes

32. Omnipaque used in vascular procedures • Hypaque is used in operative cholangeograms • Are others as well • Are light sensitive and should be stored in closed box or with something over them to protect them from light which alters the efficacy of the contrast

33. Dyes • Used for marking skin as well as detecting injury in the urinary tract • Types include: Methylene blue, Indigo carmine, and Gentian violet

34. Methylene Blue • Is a blue dye, usually diluted with normal saline, and injected into the bladder to determine leaks in the urinary tract when pelvic surgeries are being performed • May also be injected into the fallopian tubes or uterus

35. Indigo Carmine • Is a blue dye given IV to verify that bladder function and kidney function are intact • Needs to be stored out of the light as it is light sensitive

36. Gentian Violet • A purple dye primarily used to mark incision sites • Comes in a sterile marking pen which are included in most custom packs • These are what you will use to write on the labels of your medications on your sterile field

37. Staining Agents • Primarily used to identify cervical tissue that is abnormal • Types include Lugol’s Solution and Acetic Acid • Lugol’s solution has an iodine component that in normal tissue is absorbed by the cell, but in abnormal tissue it is not absorbed leaving the tissue white verses dark • The white tissue is identified as abnormal and biopsied

38. Staining Agents • Acetic Acid (vinegar) • Used as staining agent if patient is iodine sensitive or if lasers are being used • Acetic Acid makes the abnormal tissue appear whiter than normal tissue as well • With laser surgery, dark stained tissue (Lugol’s) will react less effectively with the laser

39. Local Anesthetics • Primarily used in short or minor operations • May be used in conjunction with general or regional anesthesia • Delivered by injection directly to the operative site • Will be prepared by the surgical technologist on the sterile field and given to the surgeon prior to incision and prn during surgery • Many surgeons also will administer local to the wound edges prior to closure to prolong the onset of post-operative pain

40. Local Anesthetics • Lidocaine (.5%, 1%, 1.5%, 2%) • Marcaine (Bupivicaine) .25%, .5%, .75% a. with epinephrine b. without epinephrine • Injection is with a control syringe with appropriate sized needle (27 or 25ga initial) 22ga post-incision • MUST KEEP UP WITH AMOUNTS GIVEN! CAN WRITE ON A TOWEL OR ON A GLOVE OR GOWN TAG!

41. Local Anesthetics • Cocaine • Nasal surgery • Vasoconstrictor and mucous membrane anesthetic

42. Diuretics • Given to prevent the kidneys from reabsorbing Na+ and water • Reabsorption of these can cause a variety of patient complications including but not limited to edema (swelling), pulmonary edema (fluid in the lungs), and congestive heart failure (increased circulatory blood volume which results in the heart being overworked>enlarged heart chambers>defective heart valvular function)

43. Diuretics Continued • Surgical uses: • Prevent complications previously mentioned as well as reduce intraocular pressure and to reduce intracranial pressure

44. Types of Diuretics • Different types of diuretics have different mechanisms of action • Types include: • Loop Diuretics • Thiazide Diuretics • Potassium Sparing Diuretics • Carbonic Anhydrase Inhibitors • Osmotic Diuretics

45. Loop Diuretics • diuretics that act on the ascending loop of Henle in the kidney. • They are primarily used in medicine to treat hypertension and edema often due to congestive heart failure or renal insufficiency.

46. Thiazide Diuretics • They work by inhibiting reabsorption of sodium (Na+) and chloride (Cl−) ions from the distal convoluted tubules in the kidneys. • Thiazides are often used to treat hypertension, although they are also used to treat congestive heart failure and symptomatic edema.

47. Potassium Sparing Diuretics • Potassium-sparing diuretics are commonly used to help reduce the amount of water in the body. Unlike some other diuretics, these medicines do not cause your body to lose potassium. • They are used as adjunctive therapy, together with other drugs, in the treatment of hypertension and management of congestive heart failure.

48. Carbonic Anhydrase Inhibitors • Often used for opthalmic purposes. • The drug decreases fluid formation in the eye resulting in lower intraocular pressure. • The drug forces the kidneys to excrete bicarbonate, the conjugate base of carbonic acid. By increasing the amount of bicarbonate excreted in the urine, the blood becomes more acidic. • Acidifying the blood stimulates ventilation, which increases the amount of oxygen in the blood.

49. Osmotic Diuretics • a type of diuretic that inhibits reabsorption of water and sodium. • An example is Mannitol. • Mannitol can also be used to reduce intracranial pressure.

50. Diuretics in the OR • Lasix • Bumex • Aldactone • Mannitol • These are given IV by the CRNA during surgery