Assessing and managing hypovolemia

Van Kraaij, D. J, Jansen, R. W,  & Hoefnagels, W. H. (1999). Monitoring Hypovolemia in Healthy Elderly Subjects by Measuring Blood Pressure Response to Valsalva’s Maneuver. Geriatric nephrology and urology. 9(2):73-9

According Van Kraaij, Jansen ; Hoefnagels, (1999) they recommends that the nurse pay attention to certain parameters when assessing a patient’s fluid and electrolyte status.  The nurse must know the comparison of the total intake and output of fluids, urine volume and concentration, skin turgor and tongue turgor, degree of moisture in oral cavity, body weight, thirst, tearing and salivation, appearance and temperature of skin, facial appearance, edema, vital signs, neck and hand vein filling.  Young children, elderly people and people whoa are ill are especially at risk for hypovolemia.  A weight loss of 5 % in adults and 10% in infants can occur rapidly.  A 5% weight loss is considered a pronounced fluid volume deficit; an 8% loss or more considered severe.  A 15% weight loss caused by fluid deficiency usually life threatening.   Nurse must carefully assessed the total body weight of the patient to determine if there has been changes in the body fluid volume.

Allison, R. D., Lewis, R.A., Liedtke, R., Buchemeyer, N. D., Frank, H. (2005), Early identification of hypovolemia using total body resistance measurements in long-term care facility, Gender Medicine, 2 (1) 19-34

In the words of Allison, Lewis, Liedtke, Buchemeyer ; Frank, (2005), they concluded that skin turgor is one of the best indicator that a patient is experiencing dehydration or hypovolemia.  In assessing the skin turgor or elasticity, a nurse must correctly assess the patient’s skin pinching the skin over the sternum, inner aspect of the thighs or forehead.  Some prefer to test skin turgor in children over the abdominal area and on the medial aspect of he thighs.  Normally, when the skin is pinched, the skin immediately falls back to its normal position when released.  If an individual is experiencing hypovolemia, the skin flattens more slowly after the pinch is released, the skin may remain elevated for many seconds.  For instances, we must be very carefully assess the skin elasticity of an elderly, because reduced skin turgor is commonly in older patients (those more than 55 – 66 year of age) because of primary decrease in skin elasticity.

Kimmerly, D., ; Shoemaker J., (2003). Hypovolemia and MSNA discharge patterns: assessing and interpreting sympathetic responses. American Journal of Physiology. Heart and Circulatory Physiology. 284(4):H1198-204Kobriger, A. M. (1999). Dehydration: Stopping a sentinel event. Nursing homes, 48 (10), 60 – 65

On the other hand, Kimmerly, ; Shoemaker (2003) added that unlike skin turgor, tongue turgor is not affected appreciably by age and thus is a useful assessment for all age groups.  (in an arid climate, this may not be a reliable parameter.)  On normal circumstances, the tongue has one longitudinal furrow.  Bit un a person with fluid volume deficit or hypovolemia, there are additional longitudinal furrows and the tongue is smaller.  Another assessment parameters is the moisture and oral cavity.  A dry mouth may be result of fluid volume deficit or of mouth breathing.  Normally the mucous membranes in oral cavity are moist, but when a person is experiencing hypovolemia, a person is having dryness of the membrane where the check and gum is meet that can be indicative of fluid volume deficit.

Nurses play a critical role in preventing fluid volume deficit, identifying vulnerable patients, preventing complications and reducing hospital stays.  People who are mildly dehydrated may only notice symptoms of increased thirst or dry mouth.  A profound fluid deficit, however, may be associated with circulatory collapse and death.  Severe fluid depletion is an emergency requiring rapid fluid replacement, restoration of electrolyte balance and circulatory support.

Kolecki, P. (2008). Hypovolemic Shock. eMedicine Specialies: Emergency Medicine: Cardiovascular. Available at: http://www.emedicine.com/emerg/topic532.htm retrieved Mar. 27 2008.

Based on Kolecki (2008), an accurate and frequent assessment of intake and output, weight, vital signs, central venous pressure, level of consciousness, breath sounds, and skin color should be performed to determine when therapy should be slowed to avoid volume overload. The rate of fluid administrations based on the severity of loss and the patient’s hemodynamic response to volume replacement. If the patient with severe hypovolemia is not excreting enough urine and is therefore oliguric, the health care provider needs to determine whether the depressed renal function is the result of reduced renal blood flows secondary to hypovolemia or, more seriously, to acute tubular necrosis from prolonged hypovolemia. The test used in this situation is referred to as a fluid challenge test. During a fluid challenge test, volumes of fluids are administered at specific rates and interval while the patient’s hemodynamic response to this treatment is monitored (i.e. vital signs, breath sounds, sensorium, central venous pressure, urine output). The goal is to provide fluids rapidly enough to attain adequate tissue perfusion without compromising the cardiovascular system.

Black and Jacobs. (2000). Medical-Surgical Nursing: Clinical Management for Continuity of care 5th edition . Philadelphia: W B Saunders Co.

Black and Jacobs. (2000) added, that the under most circumstances, fluids are replaced at the speed with which they are lost.  Fluid replacement need are  often calculated according to weight.  Because 1 liter weighs 1 kilogram, the amount of weight (in kilogram) lost during the period of fluid depletion approximates the volume of water deficit.  Replacement requires administration of the volume lost plus an additional 1.5 Liter to fulfill daily needs.  Fluid replacement may require several days of therapy to avoid complications associated with rapid volume infusion as inter-compartment fluid shifts and pulmonary edema.  Oral fluid resuscitation is preferable, but if the patient is unable to tolerate fluids, intravenous therapy may be required.  The type of intravenous solution is based on the patient’s fluid and electrolyte status and volume needs.

Assessing and Managing HYPOVOLEMIA

Introduction

            Hypovolemia or Fluid Volume Deficit (FVD) occurs when lost of extracellular fluid volume exceeds the intake of fluid. It occurs when water and electrolytes are lost in the same proportion as they exist in normal body fluids, so that the ratio of serum electrolytes to water remains the same.  Hypovolemia should not be confused with the term dehydration, which refers to lost of water alone with increased serum sodium levels. FVD may occurs alone or in combination with other imbalances. Unless other imbalances are present concurrently, serum electrolyte concentrations remain essentially unchanged.

Body

Assessing the patient who has this condition is a really tough one.  We should know everything in the physical assessment that consider effective in the patient.  Like for example, skin turgor test or skin recoil test is not any more reliable for older patient, but it is an indicative sign that an infant is having the disorder.  Another areas that concern is assessing the fontanel, according to the author, one way of assessing the hydration status of an infant is noting the fontanel if its bulging or has a shrill loud cry.  But for an adult one, fontanel test is not anymore reliable, because infant’s fontanel closes at 2 to 3 months for the anterior fontanel and 12 to 18 months for the posterior fontanel.  These suggest that assessing one’s health is not always applicable to anyone but it is individualized

To asses for hypovolemia, the nurse monitors and measures fluid intake and output at least every 8 hours, and sometimes hourly.  As hypovolemia develops, body fluid losses exceed fluid intake.  This loss may be in the form of excessive urination (Polyuria), diarrhea, vomiting, and so on.  Later, after hypovolemia fully develops, the kidneys attempt to conserve needed body fluids, leading to a urine output of less than 30 mL/hr in an adult.  Urine in this instance is concentrated and represents a healthy renal response.  Daily body weights are monitored; an acute loss of 0.5kg (1 lb) represents a fluid loss of approximately 500ml. (one liter of fluid weights approximately 1kg or 2.2lb.).  Vital signs are closely monitored.  The nurse observe for a weak, rapid pulse and postural hypotension (i.e. , a drop in systolic pressure exceeding 15mm Hg when the patient moves from a lying to a sitting position).  A decrease in body temperature often accompanies hypovolemia, unless there is a concurrent infection.  Skin and tongue turgor is monitored on a regular basis.  In a healthy person, pinched skin immediately returns to its normal position when released.  This elastic property, referred to as turgor, is partially dependent on interstitial fluid volume.  In a person with hypovolemia, the skin flattens more slowly after the pinch is released.  When hypovolemia is severe, the skin may remains elevated for many seconds. Tissue turgor is best measured by pinching the skin over the sternum, inner aspects of the things, or forehead.

Evaluating tongue turgor, which is not affected by age, may be more valid than evaluating skin turgor.  In the person with hypovolemia, there are additional longitudinal furrows and the tongue is smaller, because of fluid loss, the degree of oral mucous membrane moisture is also assessed; a dry mouth indicate either hypovolemia or mouth breathing.  Urinary concentration is monitored by measuring the urine specific gravity.  In a volume-depleted patient, the urinary specific gravity should be above 1.020, indicating healthy renal conservation of fluid.  Mental function is eventually affected in severe hypovolemia as a result of decreasing cerebral perfusion.  Decreased peripheral perfusion can result in cold extremities.  In patients with relatively normal cardiopulmonary function, a low central venous pressure is indicative of hypovolemia.  Patient with acute cardiopulmonary decompensation require more extensive hemodynamic monitoring of pressures in both sides of the heart to determine if hypovolemia exist

With all of the measures in replacing or hydrating the patient, we must take note peculiar care  in delivering fluid to those people: (1) infants, (2) older patients with circulatory or renal impairment, (3) patients (such as those with burns) at risk for potential plasma shifts and (4) those with extensive tissue trauma.  Burns for example, can initially cause massive shifts of fluid into interstitial space, and then after several days fluid moves back into the vascular space, increasing blood volume.  To prevent hypovolemia, the nurse identifies patients at risk and takes measure to minimize fluid losses. For example, if the patient has diarrhea, diarrhea control measures should be implemented and the replacement fluids administered. This measure may include administering Anti diarrheal medications and small volumes of oral fluids at frequent intervals .  We must also teach our clients in the importance if adequate fluid and food intake, especially when under physiologic and thermal stress.  He nurse should encourage individuals who are engaging in an strenuous activities to replace both water and electrolytes.

Another management measures that are very helpful in client condition is to increased her low residue diet, starting with BRAT (Banana, Rice, Applesauce, Toast) diet when diarrhea is the main cause of the hypovolemia.  Because low residue foods reduce stool bulk and slow than gastrointestinal transit time.  Moreover the BRAT diet contains foods that are high in pectin for which helps makes stool firm.  Offering dry crackers or toast is also beneficial to client if the client retain fluids.  Because solid foods in readily digestible carbohydrates are tolerated better than other types of food.

When possible, oral fluids are administered to help correct hypovolemia, with consideration given to the patient’s likes and dislikes.  Also, the type of fluid the patient has lost is considered, and attempts are made to select fluid most likely to replace the lost electrolytes.  If the patient is reluctant to drink because of oral discomfort, the nurse assists with frequent mouth care and provides nonirritating fluids.  The patient may be offered small volumes of fluids at frequent intervals rather than a large volume all at once.  If nausea is present, Anti-emetics may be needed before oral fluid replacement can be tolerated.  If the patient cannot drink and eat, the nurse may need to administer fluid by an alternative route (enteral or parenteral) prescribed to prevent renal damage related to prolonged hypovolemia.

Conclusion

Assessment is indeed great part of a nurse in his or her work in the hospital.  We should always take note that having the established nursing assessment helps the client in attaining his or her optimum level of functioning.  With the right assessment on the patient, the care that will be given to he patient is also appropriate.

References:

Allison, R. D., Lewis, R.A., Liedtke, R., Buchemeyer, N. D., Frank, H. (2005), Early identification of hypovolemia using total body resistance measurements in long-term care facility, Gender Medicine, 2 (1) 19-34

Black and Jacobs. (2000). Medical-Surgical Nursing: Clinical Management for Continuity of care 5th edition . Philadelphia: W B Saunders Co.

Kimmerly, D., ; Shoemaker J., (2003). Hypovolemia and MSNA discharge patterns: assessing and interpreting sympathetic responses. American Journal of Physiology. Heart and Circulatory Physiology. 284(4):H1198-204Kobriger, A. M. (1999). Dehydration: Stopping a sentinel event. Nursing homes, 48 (10), 60 – 65

Kolecki, P. (2008). Hypovolemic Shock. eMedicine Specialies: Emergency Medicine: Cardiovascular. Available at: http://www.emedicine.com/emerg/topic532.htm retrieved Mar. 27 2008.

Van Kraaij, D. J, Jansen, R. W,  ; Hoefnagels, W. H. (1999). Monitoring Hypovolemia in Healthy Elderly Subjects by Measuring Blood Pressure Response to Valsalva’s Maneuver. Geriatric nephrology and urology. 9(2):73-9