N316: Hydration and Homeostasis

Sodium (Na+)

135-145 mEq/L

Potassium (K+)

3.5-5.3 mEq/L

Calcium (Ca2+)

8.5-10.5 mg/dL

magnesium (mg2+)

1.6-2.6 mEq/L

chloride (Cl-)

95-105 mEq/L

phosphate (PO4-)

2.5-4.5 mEq/L

bicarbonate (H2CO3-)

22-26 mEq/L

Complete blood count (CBC)

RBCs + WBCs + platelets + hemoglobin

• hematocrit: % of whole blood that is RBCs

  • more fluid = less room for RBCs (∴ inverse b/w fluid and hematocrit)

  • females: 37-47%

  • males: 42-52%

basic metabolic panel (BMP)

electrolytes, BUN (blood urea N) and Crt (kidney function), glucose

comprehensive metabolic panel (CMP)

BMP + albumin + ALP + ALT + AST + bilirubin

serum osmolality

measure [solute] in blood (fluid/volume balance)

• high = fluid volume deficit

• low = fluid volume excess

urine osmolality

[solute] of urine

• 24 hr specimen collection

• discard 1st morning specimen, collect clean-catch 2 hours later

Measuring I/O: Fluid intake

ORAL (preferred)

• drinks, soups, broths

• meds

PARENTERAL 

• IV fluids

Fluid restriction interventions

• no liquids w/ meals

• limit thirst-inducing foods

• keep liquids away from bedside (ice chips OK)

• oral hygiene

• diversional activites

Parenteral/IV Solutions

Admin of fluids, electrolytes, meds, or nutrients by venous route

• ↑ vasc volume

• aseptic technique

• CAUTIs not medicare reimbursed!

isotonic: remain in intravascular compartment

hypotonic: body H2O EXITS intravascular compartment

hypertonic: body H2O ENTERS into intravascular compartment

normal blood osmolality

275-295 mOsm/kg

isotonic IV solution

250-375 mOsm/Kg

USES

• hypotension (so blood stays/doesn’t rush out and make u pass out)

• hypovolemia (keep fluid volume in place)

EXAMPLES

• 0.9% NaCl (normal saline)

• lactated ringers

NURSING CONSIDERATIONS

• fluid stays in ❤ → ❤ overloaded (heart failure) ∴ closely monitor!!!

Hypotonic IV solution

< 250 mOsm/kg

USES

• hyperglycemia (so excess sugar EXITS)

EXAMPLES

• DSW

• ≤ 0.45% NaCl (1/2 normal saline)

NURSING CONSIDERATIONS

• Rapid fluid shift → cerebral edema → excess cranial pressure (∴ admin SLOWLY!!!)

Hypertonic IV Solution

solution mOsm > serum

USES

• volume expander (water follows solute into vasc compartment)

• blood loss (reduce solute loss even while fluid is exiting)

• major burns (promote circulation of blood to area ∴ healing)

EXAMPLES

• D5NS, D51/2NS

• D5LR

• 3, 5% NaCl (critical situations)

• D10W, D20W

Peripheral Vascular Access Device

Vascular Access Device (VAD)

• gauge # inv needle opening diameter

Butterfly needle: short, beveled needle w/ flexible plastic straps

• single-dose (DON’T LEAVE IN PLACE)

• blood draws

Midline Peripheral Catheter: insert into antecubital fossa → larger arm BVs

• 5-14 days life

Peripheral intravenous lock (PIV): inserted into vein

PVAD assessment

SUBJECTIVE DATA

• Demographics: age, sex, height, BMI

• Hx: kidney disease, HTN, diabetes, thyroid issues

• Current concerns: fever, polydipsia, limited urine swelling, weight fluctuations

• I/O: average fluid intake per 24 hr, special diet, added salt/sugar

• Fluid Elimination: frequency, nocturia, wounds/drainage

• Meds: OTC, Rx

• Lifestyle: activity level, substance abuse

OBJECTIVE DATA

• Skin: moisture, turgor, edema (1-4)

• Mucous Membranes: tongue turgor, dryness

• CV System: orthostatic hypotension, cap refill, venous filling

• Respiratory system: crackles, moist rales

• Basic Metabolic Panel (BMP) 

• Daily weights

• Pulse

  • K+, Mg2+ imbalances → dysrhythmia

  • fluid volume deficit → tachycardia

Central Venous Access Device (CVAD)

Inserted into subclavian or internal jugular vein (major veins)

TYPES

• peripherally inserted central catheter (PICC)

• non-tunneled central venous catheters

• tunneled central venous catheters

• implanted ports

USES

• admin highly irritating products more directly

• long-term infusion

  • parental nutrition, blood draws, lumens

  • ✅: ↓ phlebitis, extravasation, and infiltration risk

NURSING CONSIDERATIONS

• CLABSI risk

  • Intervention: patient education, hand hygiene, sterile insertion, chlorhexidine treatment, daily review, etc.

• requires consent

• must check placement w/ radiography

• air embolus or dysrhythmia

  • intervention: avoid BP or blood draws on extremity w/ port placement

IV Complications

Hematoma: localized mass of blood outside the BV

• cause: nicked vein

• intervention: pressure on vein when discontinuing IV (prevent leaks)

Infiltration: NON-HARMFUL IV fluid leaks into surrounding tissue → swelling, burning sensation

• cause: dislodged IV

• intervention: stop infusion ASAP, NO pressure on area, elevate affected arm (promote excess fluid absorption)

Extravasation: HARMFUL IV fluid leaks into surrounding tissue → blanching, pain

• cause: dislodged IV

• intervention: stop infusion ASAP, admin antidote, elevate affected arm

Phlebitis: vein inflammation

• causes: irritation, vessel trauma, low flow rate

• intervention: discontinue IV/restart elsewhere, warm to cold compress, use SMALLEST possible gauge

Thrombophlebitis: thrombosis and inflammation

• causes: hypertonic/acidic IV solution, leg IV

• interventions: STOP IV/restart elsewhere

Local infection: m/o contamination of cannula/IV site

• causes: leaving same cath for 96+ hours, poor aseptic technique

• interventions: remove IV, apply sterile dressing, admin antibiotics

Nerve Injury

• direct: sharp/acute pain @ site/radiating on arm (pins/needles) that persists post-removal

• compression: pain/tingling 24-96 hours post-insertion

Septicemia: m/o in circulatory system → high WBCs, tachy, fever, chills, etc.

Fluid overload: too much/too fast IV admin → edema, crackles distended neck vein

• interventions: high Fowler’s position, diuretics, admin O2 if needed

Air/cath embolus: air/cath piece inside IV tube → sudden Δ in mental status, light-headedness

• interventions: L Trendelenburg position