NurseReview.Org - Third Spacing: Where has all the fluids gone?

Slide 1: 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.

Slide 2: 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

Slide 3: 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

Slide 4: 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

Slide 5: 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

Slide 6: How Fluids Affect Cells: Isotonic Solutions

Slide 7: How Fluids Affect Cells: Hypertonic Solutions

Slide 8: How Fluids Affect Cells: Hypotonic Solutions

Slide 9: 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

Slide 10: 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

Slide 11: 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

Slide 12: Mediators of SIRS and MODS

Slide 13: 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

Slide 14: 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

Slide 15: 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

Slide 16: 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

Slide 17: 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)

Slide 18: 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

Slide 19: 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