Third-Spacing: Where Has All the Fluid Gone? By Marcia Bixby, RN, CS, CCRN, MS Nursing made Incredibly Easy! September/October 2006 2.5 ANCC/AACN contact hours Online: http://www. nursingcenter .com © 2006 by Lippincott Williams & Wilkins. All world rights reserved.

Fluids 101 Fluids bring nutrition and oxygen into the cells and remove wastes Fluid is divided into two compartments: intracellular and extracellular Extracellular is divided into interstitial and intravascular

Fluids bring nutrition and oxygen into the cells and remove wastes

Fluid is divided into two compartments: intracellular and extracellular

Extracellular is divided into interstitial and

intravascular

Fluids 101 The body’s fluid should be in balance; volume entering the body = volume leaving the body Fluid loss occurs via urine, sweat, stool, and incidental losses from respiratory effort

The body’s fluid should be in balance; volume entering the body = volume leaving the body

Fluid loss occurs via urine, sweat, stool, and incidental losses from respiratory effort

On the Move Diffusion: Passive movement of fluid from an area of higher concentration to an area of lower concentration Osmosis: Water movement through a selectively permeable membrane from an area of lower concentration to an area of higher concentration

Diffusion: Passive movement of fluid from an area of higher concentration to an area of lower concentration

Osmosis: Water movement through a selectively permeable membrane from an area of lower concentration to an area of higher concentration

On the Move Active transport: Movement of molecules against a concentration as they move from an area of lower concentration to an area of higher concentration; this movement requires energy Third spacing occurs when the fluid is “trapped” in the interstitial spaces

Active transport: Movement of molecules against a concentration as they move from an area of lower concentration to an area of higher concentration; this movement requires energy

Third spacing occurs when the fluid is “trapped” in the interstitial spaces

How Fluids Affect Cells: Isotonic Solutions

How Fluids Affect Cells: Hypertonic Solutions

How Fluids Affect Cells: Hypotonic Solutions

Decreased Oncotic Pressure Loss of albumin or protein leads to decreased oncotic pressure, causing fluid to “leak” from the intravascular space to the interstitial space Due to the loss in circulating fluid volume, cardiac output decreases

Loss of albumin or protein leads to decreased oncotic pressure, causing fluid to “leak” from the intravascular space to the interstitial space

Due to the loss in circulating fluid volume, cardiac output decreases

Causes of Fluid Shifts Albumin losses can occur in liver failure, liver dysfunction, and malnutrition Albumin losses can lead to fluid shifting into the peritoneum, causing ascites Destruction of endothelial cells, such as in bowel surgery, can cause fluid to move and be trapped in the interstitial spaces Fluid trapped in the lungs can lead to pulmonary edema

Albumin losses can occur in liver failure, liver dysfunction, and malnutrition

Albumin losses can lead to fluid shifting into the peritoneum, causing ascites

Destruction of endothelial cells, such as in bowel surgery, can cause fluid to move and be trapped in the interstitial spaces

Fluid trapped in the lungs can lead to pulmonary edema

Inside the Cells Interstitial fluid trapping can cause compression of the microvasculature, resulting in hypoperfusion and ischemia Inflammatory “mediators” are released into the bloodstream, which can lead to systemic inflammatory response syndrome (SIRS) Multiple organ dysfunction syndrome (MODS) occurs, leading to organ failure and death

Interstitial fluid trapping can cause compression of the microvasculature, resulting in hypoperfusion and ischemia

Inflammatory “mediators” are released into the bloodstream, which can lead to systemic inflammatory response syndrome (SIRS)

Multiple organ dysfunction syndrome (MODS) occurs, leading to organ failure and death

Mediators of SIRS and MODS

What Happens When Fluids Shift? With decreased circulating volume, baroreceptors in the aorta are activated Sympathetic nervous system releases epinephrine and norepinephrine, causing vasoconstriction and an increased heart rate Kidneys launch the renin-angiotensin-aldosterone system in response to a lower glomerular filtration rate All this happens with the goal of increasing circulating volume, blood pressure, and cardiac output

With decreased circulating volume, baroreceptors in the aorta are activated

Sympathetic nervous system releases epinephrine and norepinephrine, causing vasoconstriction and an increased heart rate

Kidneys launch the renin-angiotensin-aldosterone system in response to a lower glomerular filtration rate

All this happens with the goal of increasing circulating volume, blood pressure, and cardiac output

Fluid Shift in the Bowel Causes abdominal distention Measure bladder pressure and abdominal girth at least every 4 to 8 hours while signs are abnormal

Causes abdominal distention

Measure bladder pressure and abdominal girth at least every 4 to 8 hours while signs are abnormal

Making the Grade A patient’s intra-abdominal pressure (IAP) determines if he has intra-abdominal hypertension. According to the World Society of Abdominal Compartment Syndrome, there are four grades of intra-abdominal hypertension: Grade I: IAP of 12 to 15 mm Hg Grade II: IAP of 16 to 20 mm Hg Grade III: IAP of 21 to 25 mm Hg Grade IV: IAP of > 25 mm Hg

A patient’s intra-abdominal pressure (IAP) determines if he has intra-abdominal hypertension.

According to the World Society of Abdominal Compartment Syndrome, there are four grades of intra-abdominal hypertension:

Grade I: IAP of 12 to 15 mm Hg

Grade II: IAP of 16 to 20 mm Hg

Grade III: IAP of 21 to 25 mm Hg

Grade IV: IAP of > 25 mm Hg

Complications of Abdominal Swelling Decreased cardiac output leads to decreased blood pressure, which causes: increased pressure on the aorta and the iliac and femoral arteries, leading to decreased cardiac output and decreased blood pressure impaired kidney function impaired blood flow to the bowel, liver, and spleen

Decreased cardiac output leads to decreased blood pressure, which causes:

increased pressure on the aorta and the iliac and femoral arteries, leading to decreased cardiac output and decreased blood pressure

impaired kidney function

impaired blood flow to the bowel, liver, and spleen

Monitoring the Patient Fluid shift will either resolve over the next several hours (up to 48 hours) or the patient will continue to develop bowel edema and, eventually, ischemia Closely monitor vital signs, urine output, peripheral perfusion, mental status, ventilation/perfusion status, hematocrit/hemoglobin, serum electrolytes (elevated lactate may indicate bowel ischemia)

Fluid shift will either resolve over the next several hours (up to 48 hours) or the patient will continue to develop bowel edema and, eventually, ischemia

Closely monitor vital signs, urine output, peripheral perfusion, mental status, ventilation/perfusion status, hematocrit/hemoglobin, serum electrolytes (elevated lactate may indicate bowel ischemia)

Fluid Resuscitation Administer maintenance I.V. isotonic fluid plus intermittent colloids (i.e., albumin); pulls fluid from the interstitial spaces into the intravascular space Small dose of a loop diuretic, such as furosemide (Lasix) may be ordered if kidneys can’t get rid of the excess fluid If hemoglobin is low, infuse blood products, such as packed red blood cells, as ordered to help increase oxygen and pull fluid from the interstitial space

Administer maintenance I.V. isotonic fluid plus intermittent colloids (i.e., albumin); pulls fluid from the interstitial spaces into the intravascular space

Small dose of a loop diuretic, such as furosemide (Lasix) may be ordered if kidneys can’t get rid of the excess fluid

If hemoglobin is low, infuse blood products, such as packed red blood cells, as ordered to help increase oxygen and pull fluid from the interstitial space

If Bowel Ischemia Occurs A kidney-ureter-bladder X-ray (KUB) may be done; it will show bowel edema and any “free air,” which may indicate bowel perforation A CT scan can detect worsening bowel edema, inadequate perfusion, and hematomas Patient may need further surgery to repair a perforated bowel or to decrease edema

A kidney-ureter-bladder X-ray (KUB) may be done; it will show bowel edema and any “free air,” which may indicate bowel perforation

A CT scan can detect worsening bowel edema, inadequate perfusion, and hematomas

Patient may need further surgery to repair a perforated bowel or to decrease edema