Urinary Excretion
When a person is supine, urine must leave the kidney against an upward gradient. Hence mobility for the bedfast patient preserves urinary function. Any statis of urine in the renal pervis for even a few days may lead to infection or the formation of renal calculi, urinary tract stones.
Protein breakdown, bone demineralization, and loss of muscle tone during prolonged immobility contribute to marked changes in urinary excretion. The nephron continues to be selective of constituents in the blood, excreting those in excess and preserving those in defict. Minerals and salts are in excess in blood plasma as a result of bedrest, and thus the nephron increases excretion of these. These particles become ideal nuclei for the formation of renal calculi. Their precipitation is favored by statis, alkaline urine, decreased volume of urine, and bacterial invasion.
Nursing intervention can prevent urine statis through frequently changing the patient`s position and avoiding a supine position for too long a period of time. An alkaline urine occurs during bedrest because of a lack of muscular activity; acid end products decrease and the urine pH rises. Acid-ash between-meal snacks such as cranberry juice or cereals can help overcome this and should be a part of every immobilized patient`s care plan.
Forcing fluids is perhaps the simplest and most effective means for preserving urinary function; yet it is often overlooked or given only lip service. Keeping a pitcher of water at the bedside and changing it faithfully is likely to be considered adequate provition of fluid intake, but unless you actually assist the patient in drinking the water, it will do no good. This assistance is different for every patient. It may mean keeping the water within easy reach or pouring it when strength is diminished. But two actions are essential : (1) ofter the water frequently as you encourage its use and (2) carry out effective teaching as to its importance for body fluids as well as for urinary excretion.
Prevention or urinary tract infection depends on nursing measures. Indwelling catheters should be used only when other measures to keep the patient dry and the bladder empty have failed. During their use, meticulous perineal care and cleansing of the catheter where it emerges from the meatus must be done at least once daily.
References :
Browse, N.L., Physiology and Pathology of Bedrest. Springfield, III.: Charles C. Thomas, Publisher, 1965.
Olson, Edith V., “The Hazards of Immobility”, American Journal of Nursing, 67: No.4, 1971.
Murray, RB and Zentner JP., Nursing Concepts for Health Promotion, Second Edtion, Prentice-Hall, Inc, Englewood Cliffs, N.J, 1979.
