Fluid and Electrolytes

intracellular fluid (ICF)

makes up 60-70%

extracellular fluid (ECF)

makes up 30-40%

ECF includes..

intersitial fluid (between cells), vascular fluid (plasma), transcellular fluid (CSF, intraocular, joint fluid)

(BLANK) primarily controls extracellular balance

sodium

(BLANK) primarily controls intracellular balance

potassium

90% of bodys sodium is in

extracellular compartment

98% of body’s potassium is in

intracellular compartment

What follows movement of sodium

chloride

Hydrostatic pressure

pushes fluid out of capillaries

colloid osmotic pressure

draws fluid into capillaries

Capillary hydrostatic pressure is greater or less than interstitial hydrostatic pressure

greater than

Normal routes for elimination of water and electrolytes

urine, stool, skin, lungs

aldosterone

primary driver for ECF volume; release in response to decreased renal blood flow and elevated potassium levels

ADH is secreted by ?

posterior pituitary

Function of ADH

regulates renal excretion of water but not sodium

Osmolality imbalance deficit

deficit in fluid volume causes sudden weight loss, skin tenting, dry mucus membranes, rapid thready pulse, orthohypo, oliguria

Osmolality imbalance excess

excess in fluid causes sudden weight gain, edema, vascular overload, bounding pulse, pulmonary edema, dyspnea

Hypertonic

increased ECF osmolality causes cells to shrink

Hypotonic

decreased ECF osmolality causes cells to swell

normal sodium level

135-145

hypernatremia

NA+ level > 145, too concentrated

hyponatremia

NA+ level < 135, too dilute

Normal chloride level

96-106

Hyperchloremia

chloride level > 106

Hyperchloremia associated with

hypernatremia and dehydration

Hypochloremia

chloride level < 96

Hypochloremia associated with

GI losses such as V/D/ NG suction

Normal magenesium level

1.3-2.1

hypermagnesemia

magnesium level > 2.1

hypermagnesemia causes

decrease in neuromuscular excitability

S/S of hypermagnesemia

flushing, diaphoresis, hypotension, bradycardia

Hypomagnesemia

magnesium level < 1.3

most common cause of hypomagnesemia

excessive alcohol intake

Hypomagnesium causes

increase in neuromuscular excitabillity (chvostek and trousseau)

Causes massive fluid shift; give large amount of fluids in first 24 hours

Burns

first degree burns

epidermis only; localized pain and erythema

second degree burns

epidermis and some of dermis

second degree burns - superficial partial thickness

sensation is intact; fluid filled blisters appear within minutes

second degree burns - deep partial thickness

loss of sensation; will cause scar

Third degree burn

destroys dermis, epidermis, subcutaneous tissue

third degree burns require what to heal

grafting

fourth degree burn

full thickness burn the destroys all layers as well as tendons, muscles, bones

Acute Kidney Injury (AKI)

accumulation of nitrogenous waste products

Labs seen for AKI

increased BUN and serum creatinine

Is AKI reversible?

yes

Prerenal AKI

reduced blood flow to kidneys

Intrinsic AKI

direct damage to kidneys

postrenal AKI

obstruction of bladder

When GFR drops <60 ml/min, this indicates

chronic kidney injury