McKenna's Pharmacology for Nursing, 2e

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C H A P T E R 5 1 Diuretic agents

and HF, which could be exacerbated by the large shifts in fluid related to use of these drugs. Routine use during pregnancy is not appropriate; these drugs should be reserved for situations in which the mother has patho- logical reasons for use, not pregnancy manifestations or complications, and only if the benefit to the mother clearly outweighs the risk to the fetus. Adverse effects The most common and potentially dangerous adverse effect related to osmotic diuretics is the sudden drop in fluid levels. Nausea, vomiting, hypotension, light- headedness, confusion and headache can be accompa- nied by cardiac decompensation and even shock. People receiving these drugs should be closely monitored for fluid and electrolyte imbalance. ■ ■ Assess for contraindication or cautions: any known allergies to thiazides or sulfonamides to prevent hypersensitivity reactions ; fluid or electrolyte disturbances, which could be exacerbated by the diuretic or render the diuretic ineffective ; gout, which reflects an abnormal tubule function and could be worsened by the diuretic or reflect a condition that would render the diuretic ineffective ; glucose tolerance abnormalities, which may be exacerbated by the glucose elevating effects ; liver disease, which could alter the metabolism of the drug, leading to toxic levels ; systemic lupus erythematosus, which frequently affects the glomerulus and could be exacerbated by the use of a thiazide or thiazide-like diuretic ; hyperparathyroidism and bipolar disorder, which could be exacerbated due to increased serum concentrations of calcium ; and current status of pregnancy or breastfeeding because of the potential for adverse effects on the fetus or baby. ■ ■ Perform a physical assessment to establish baseline data before beginning therapy, to determine the effectiveness of therapy and to evaluate for occurrence of any adverse effects associated with drug therapy. ■ ■ Inspect the skin carefully for signs and symptoms of oedema; note the extent and degree of oedema, including evidence of pitting, to provide a baseline as a reference for drug effectiveness ; check skin turgor to determine hydration status. ■ ■ Assess cardiopulmonary status, including blood pressure and pulse, and auscultate heart and Care considerations for people receiving diuretics Assessment: History and examination

lung sounds for abnormalities to evaluate fluid movement and state of hydration and monitor the effects on the heart and lungs. ■ ■ Obtain an accurate body weight to provide a baseline to monitor fluid balance. ■ ■ Monitor intake and output and assess voiding patterns to evaluate fluid balance and renal function. ■ ■ Evaluate liver status to determine potential problems in drug metabolism. ■ ■ Monitor the results of laboratory tests, including serum electrolyte levels, especially potassium and calcium, uric acid and glucose levels, to determine the drug’s effect , and renal and liver function tests to identify the need for possible dose adjustment and toxic effects . ■ ■ Administer oral drug with food or milk to buffer the drug effect on the stomach lining if GI upset is a problem. ■ ■ Administer intravenous diuretics slowly to prevent severe changes in fluid and electrolytes. ■ ■ Continuously monitor urinary output, cardiac response and heart rhythm of individuals receiving intravenous diuretics to monitor for rapid fluid switch and potential electrolyte disturbances leading to cardiac arrhythmia. Switch to the oral form, which is less potent and easier to monitor , as soon as possible, as appropriate. ■ ■ Administer oral form early in the day so that increased urination will not interfere with sleep. ■ ■ Monitor the dose carefully and reduce the dose of one or both drugs if given with antihypertensive agents; loss of fluid volume can precipitate hypotension. ■ ■ Monitor the response to the drug (e.g. blood pressure, urinary output, weight, serum electrolytes, hydration, periodic blood glucose monitoring) to evaluate the effectiveness of the drug and monitor for adverse effects. ■ ■ Assess weight daily to evaluate fluid balance. ■ ■ Check skin turgor to evaluate for possible fluid volume deficit , and assess oedematous areas for changes, including a decrease in amount or degree of pitting . ■ ■ Provide comfort measures, including skin care and nutrition consultation, to increase compliance with drug therapy and decrease the severity of adverse effects; provide safety measures if dizziness and weakness are a problem to prevent injury. ■ ■ Provide potassium-rich or low-potassium diet as appropriate to maintain electrolyte balance and replace lost potassium or prevent hyperkalaemia. Implementation with rationale