Page 366 - Fluid, Electrolyte, and Acid-Base Disorders in Small Animal Practice

356 FLUID THERAPY

10,49
will touch hair during the procedure. If it is not possi- humans. Its activity is not diminished by the
ble to clip a sufficiently wide area, consider wrapping presence of organic matter such as blood and is
the appendage or neck with a temporary bandage to not appreciably degraded by alcohol, and there is
hold down the hair coat and keep it out of contact with considerable residual activity after a single applica-
the catheter. tion. The Food and Drug Administration does not
2. Wash your hands and apply a germicidal lotion (e.g., recommend chlorhexidine soap as a surgical scrub
Avagard [3M, St. Paul, Minn.], Citrus II [Beaumont for cats.
Products, Kennesaw, Ga.], IC Lotion [R&R Lotion, b. Povidone-iodine (Betadine 7.5% scrub [Perdue,
Scottsdale, Ariz.], or Purell [GOJO Industries, Akron, Stamford, Conn.], Poviderm 7.5% scrub [Vetus/
Ohio]). Don a clean examination glove on the domi- Burns Veterinary Supply, Farmers Branch, Tex.]):
nant hand using a “no touch” technique. Treat this This formulation of iodine supplies the antiseptic
glove as though it were sterile, and do not touch its activity of iodine in a form that is less irritating
fingers with your bare hand when removing it from and less staining than iodine or tincture of iodine.
the container. The antiseptic activity is reduced in the presence of
3. Local anesthesia with subcutaneous lidocaine often organic matter, and this formulation is more likely
facilitates catheterization. Although some animals to cause skin irritation than is chlorhexidine. 59,60
react to the transient sting of injected lidocaine, this It is the preferred antiseptic for use on cats.
is often less stressful than the sensation produced by c. Two percent iodine, tincture of iodine: Iodine is
a large-gauge catheter being forced through the skin. bactericidal at very low concentrations. In the
Local anesthesia also provides the option of making a absence of organic matter, a 1% solution kills most
facilitation incision at the venipuncture site (see the surface bacteria within seconds and is more effec-
Percutaneous Facilitation Procedure section). If local tive than povidone-iodine. 41,76 It discolors hair
anesthesia is desired, it should be done immediately and skin and frequently causes skin irritation.
after clipping to allow time to take effect while the skin d. Ethyl alcohol, isopropyl alcohol: These agents are
is prepared. The skin is wiped once with an alcohol- typically used as 70% solutions. By themselves, they
soaked cotton ball, and the venipuncture site is are reasonable germicidal agents for initial skin
anesthetized with 0.1 to 0.5 mL of lidocaine/bicar- preparation, but they do not kill spores, require
bonate 9:1 mixture administered subcutaneously. By wet contact for at least 2 minutes, and have no
mixing nine parts of lidocaine with one part of sodium residual activity. 8,78 Hence, they are not particu-
bicarbonate solution, the sting of lidocaine is larly useful patient skin antiseptics when the goal
reduced. 53,64 If made in advance, the lidocaine/bicar- is to limit skin colonization at an insertion site
7
bonate mixture should be used within 1 month under a catheter dressing. They are commonly
because the lidocaine in this mixture degrades at a rate used to remove excess surgical scrub from the
of approximately 11% per week. 82 prepared skin site during catheterization. The ger-
4. The skin must be cleaned for at least 2 and preferably micidal activities of iodine, povidone-iodine, and
3 minutes with cotton balls freshly soaked with the chlorhexidine are increased in the presence of ethyl
surgical scrub of choice. Do not use containers of alcohol. There appears to be no advantage to using
premade antiseptic-soaked gauze or cotton balls; peo- isopropyl alcohol over sterile saline as a final rinse
ple reaching into the container with their bare hands to remove residual antiseptic soap. 60 Isopropyl
contaminate these. Most antiseptic soaps require alcohol causes vasodilatation at the site of applica-
continuous wet contact for that entire time to be tion and may promote cutaneous bleeding during
effective. This means that there is no rinsing with venipuncture. This effect may be even more pro-
alcohol or water between scrubs until the full nounced when using rubbing alcohol, which has
2 to 3 minutes have elapsed. Frequent changing of additional rubefacient ingredients. If the patient’s
the cotton balls facilitates removal of surface debris. skin is abraded, an alcohol rinse should be avoided
The following antiseptic agents are useful: altogether in favor of sterile saline.
a. Chlorhexidine gluconate 4% (Hibiclens, G.C. 5. Residual soap solution is removed from the skin and
America, Alsip, Ill.; Chlorhexiderm, DVM surrounding hair with cotton balls or gauze sponges
Pharmaceuticals, Miami), chlorhexidine diacetate soaked in alcohol, hydrogen peroxide, sterile water,
2% (Nolvasan, Fort Dodge Animal Health, Over- or sterile saline solution. Soap left on the skin and coat
land Park, Kan.): Chlorhexidine is active against a will cause dermatitis—remove all of it.
broad spectrum of gram-positive and gram-nega- 6. If desired, the skin may be painted with a povidone-
tive bacteria. It is more effective than povidone- iodine solution or an iodine tincture. The solution is
iodine at preventing catheter-related infection in allowed to dry before catheter insertion.