Fluid Imbalances

patho exam 3

HYPOVOLEMIA

 (FLUID VOLUME DEFICIT) [FVD]

Isotonic FVD

Loss of extracellular fluid (ECF)

equal fluid and electrolytes lost, no fluid shift bc intra and extracellular [na] is the same

shrunken vessel, no fluid or cell changes other than less volume

Isotonic FVD causes

•Vomiting, diarrhea, GI suctioning, sweating, hemorrhage

low nutrition due to nausea, eating less

hypovolemia FVD diagnostic

•Sodium - normal

•BUN increased

•Hgb & Hct elevated – concentrated RBCs

•Urine specific gravity - increased, dark urine

decreased urine output (under 400ml/day)

Hypovolemia FVD: Clinical Manifestations

dw

dry membranes

flat neck vein

poor turgor

BP initially increases, but goes down eventually

increased HR, weak

high temp

dizzy weak confused

OH

less urine

cold clammy skin

treating hypovolemia FVD

replace fluids

oral replacement if not severe

IV NS to expand fluid volume without shifting water

Fluid challenge

test renal system, give 100-200 lm IVF first and assess for urine output to see if kidneys will handle extra fluid well

NI for hypovolemia FVD

I/O, DW, vitals, LOC, breath sounds

Avoid over correction and overhydration – will see signs of fluid excess such as cough, crackles in lungs, increased urine output

hypovolemia r/t hemorrhage requires

transfusion

HYPERVOLEMIA

(FLUID VOLUME EXCESS) [FVE]

hypertonic FVD

increased [na] concentrate, more water lost than solute

body tries to REHYDRATE by stealing water from the cell - cells shrink

in hypertonic, the water moves ____ from cell to blood bc of

passively

increased osmotic pressure

causes of hypertonic FVD

Severe GI losses from diarrhea, vomiting, NG

Sweating

Diabetic Ketoacidosis – increased glucose and ketones concentrate blood and fluid loss

Fluid shifts – ascites, burns, bowel obstruction

Hemorrhage

Decreased fluid intake

Increase sodium intake

CM and labs of hypervolemia FVD

•Dehydration – dry mucous membranes, poor skin turgor, thirst, weight loss

•CV - Increased HR, decreased BP, orthostatic hypotension, weak thready pulse

•Labs – BUN, Cr, Hgb & Hct, high

•Sodium increased

•CNS - Behavior changes – irritability, restless, disorientation

Thirsty after eating a high salt meal or after not drinking enough due to decreased urine output to conserve fluid.

Treatments for Hypertonic FVD

Hypotonic IVFs (add fluid without solute)

Volume increase will decrease concentration and cause osmotic pressure in cell to pull fluid back to rehydrate cells

Will see increase urine output with increased hydration

Transfusion if hemorrhage

Treat underlying cause

Hypotonic FVE

too much water, not enough [solute]

fluid in the blood becomes too dilute, causing osmotic pressure to increase in the cell, causing more fluid into cells, causing cell swelling

causes of FVE hypotonic

•Increase intake of dilute oral fluids

•Increase hypotonic IV fluids

•Decrease intake of sodium

•Post-op IV use in OR

•Increased anti-diuretic hormone – fluid retention and decreased urine output

diagnostics of FVE hypotonic

Sodium level low

BUN and H & H will be low due to dilution

Decreased specific gravity

Chest x-ray – pulmonary congestion

Urine sodium may be high if kidney trying to excrete

CM of hypervolemia

cell swells, increased ICP

early: HA, N/V, sweating

progressing - irritability, confusion, changes in LOC, increased BP/RR/decreased HR

late: delirium, convulsion, coma, death

edema, JVD, cackles, cough, bounding pulse, weight gain

hypotonic hypervolemia treatment

early: fluid restriction

progressing: hypertonic NS to pull fluid out from the cells and decrease ICP

• use with diuretic

• neuro checks

  • medication is mannitol - concentrate blood and pull fluid out of cell

critical, monitor for overcorrection

extracellular FVE

Swelling produced by expansion of interstitial fluid volume

Extracellular Fluid Volume Excess: Vascular Causes

Causes

Increased capillary hydrostatic pressure – pushes fluid out

Decreased capillary oncotic pressure – can’t pull fluid back in

Increased capillary permeability – more fluid passes through membrane

Discussed in slides 17-19 on pre-class power point

Causes

Heart failure-increase venous pressure

Sodium and water retention

Low albumin, malnutrition

pulling pressure vs pushing pressure

pulling: venous, albumin, pulls interstitial fluid back to vein

pushing: from the pumping of the heart

Colloid Osmotic Pressure

generated by albumin in venous end that pulls unoxygenated blood back to the circulation and it returns to heart

low albumin - low osmotic pressure

not enough pressure to pull fluid back to vein leads to edema

Extracellular Fluid Volume Excess: Vascular signs

Signs and symptoms of fluid excess

Pulmonary edema –cough, crackles

Weight gain

Jugular vein distention

Increase HR, pulse bounding

Extremities – edema, poor pulses, taut skin

treating extracellular fve

Diuretics

Low sodium diet

Increase protein in diet

Treat underlying condition

If albumin low- increase protein in diet or albumin transfusion

third spacing

response to injury, where fluid (from the blood) goes to tissue to try and heal it

causes decrease in vascular volume

return back in 3-5 days after injury - fve

must anticipate this happening!!

increased third spacing with major injuries, whole body injury

phases of third spacing

1. loss phase

2. reabsorption phase

phase 1 - loss phase

loss of fluid and PRO from vascular space to interstitial space (fluid sits in tissue)

24-72 hrs

surgery, burns, injury

measure with DW, output, hypovolemia CM

treat with large amt of fluids to prevent shock

Phase 2 - Reabsorption phase

overhydration

fluid goes back to vascular space after healing starts

increased urine output (need to decrease IV fluid)

monitor fluid overload

diuretics, watch for edema/BP, assessments

You are the day nurse caring for four clients on a medical-surgical unit. Which of these clients should you be expect to be most at risk of fluid volume deficit?

A. The client NPO since midnight for surgery

B. The client with 2+ pitting edema in lower extremities

C. The client with end stage renal failure

D. The client with gastroenteritis

D. The client with gastroenteritis

a is not that deep, D is the one w GI prob which is lots of fvd cause