Medication Administration for Pediatrics Kim Martin,RN,MSN Nursing Instructor Harrisburg Area Community College Summer 2012

Physiological Attributes Increased Total body water Increased Membrane permeability, skin and blood brain barrier Decreased body fat Immature kidney and liver function Immature temperature regulation Increased absorption of drug, decreased blood levels of water soluble drugs Increased CNS distribution and neurotoxicity, enhanced topical absorption Increased absorption of fat soluble drugs Prolonged excretion of metabolism of certain drugs Dehydrates easily, increasing concentration of drugs

Pharmacokinetics Rates of absorption is lower than adults Prolonged gastric transit time and variable gastric pH lead to diminished absorption Frequent feedings may impede drug absorption Low peripheral perfusion and immature heat regulation can decrease absorption Immature kidney and liver The average pH is lower, i.e., acidity is greater,

Metabolism Drug metabolizing enzymes if infants are immature More drugs in the circulatory system may increase drug toxicity

Distribution Low concentration of plasma proteins an diminished protein- binding capacity allow drugs to be more available in the circulation Greater permeability of the blood brain barrier, allows for rapid access of drugs to the CNS Total body water is 80% compared to adult 50% Higher doses of water soluble drugs may be needed to achieve therapeutic effects

Excretion Infant’s kidney’ have higher resistance to blood flow, lower GFR with decreased ability to concentrate urine Infants may secrete drugs more slowly, increasing risk of drug accumulation

Pediatric Fluid Management Influencing Factors Increased body surface area Increased metabolic rate Body surface; The ratio of surface area to mass is much larger for babies, so they cool down faster than adults. As a result, babies can catch a chill even when adults feel warm.

Body Surface 2/3 of insensible fluid loss occurs through the skin 1/3 of insensible fluid loss is through the respiratory system Children have greater body surface, larger quantities of fluid are lost via this route

Fluid Balance Total body Weight (TBW) Intracellular Fluid (ICF) The water contained within the cells Extracellular Fluid (ECF) Fluid outside the cells

Fluid Requirements Increased Fever Sweating Vomiting Diarrhea Diabetes Burns Decreased Meningitis Congestive Heart Failure Renal Failure

Calculating Daily Fluid Maintenance Requirements 1-10kg=100 ml/kg 11-20kg=1000ml+50ml/kg for each kg above 10 kg 21-30kg=1500ml+20ml/kg for each kg above 20 kg OUTPUT I ml/kg/hr 10 lb child = 10 divided by 2.2 = 4.5 kg x 100 ml/kg=450 divided by 24= 18.9ml/hr 8lb= 8 divided by 2.2= 3.6 x100ml/kg= 360 ml divided by 24=15 ml/hr 18 kg ( 40 lb ) 1000ml+ 8x 50ml/kg (400ml)= 1400ml divided by 24 = 58.3ml/hr 25kg (48lb) 1500 + 5 x 20/kg (100ml)=1600 divided by 24= 66.6ml/hr

One of the most important roles of the health care provider is accurate measurement of intake and output to assess fluid balance