Module 9 of 9 · Free NCLEX Prep Course · The RN Network
Caring for clients with acute, chronic, and life-threatening physical conditions: fluid and electrolytes, acid-base, medical emergencies, and the equipment that keeps unstable clients alive.
Hypokalemia (<3.5): weakness, cramps, flat T/U waves, digoxin toxicity risk. Replace orally or IV on a pump — never IV push; check magnesium too (low mag keeps K+ low).
Hyponatremia (<135): confusion, headache, seizures at extremes. Correct slowly (osmotic demyelination risk); fluid restriction for dilutional causes (SIADH).
Hypernatremia (>145): thirst, dry mucosa, restlessness — usually a water deficit; replace water slowly (cerebral edema risk).
Hypocalcemia: Trousseau and Chvostek signs, tetany, laryngospasm — common after thyroid/parathyroid surgery; keep calcium gluconate available.
Fluid volume overload: crackles, JVD, edema, weight gain (1 kg = 1 L) — daily weights are the single best fluid status measure. Deficit: orthostatic hypotension, tachycardia, poor turgor, concentrated urine.
Acid-Base and ABG Interpretation
Steps: 1) pH acidotic (<7.35) or alkalotic (>7.45)? 2) Which value matches the pH direction — CO2 (respiratory) or HCO3 (metabolic)? ROME: Respiratory Opposite, Metabolic Equal. 3) Compensation present?
Respiratory alkalosis = hyperventilation (anxiety, pain, early sepsis) — treat the cause, coach slow breathing.
Metabolic acidosis = DKA, renal failure, severe diarrhea, lactic acidosis — treat the cause; expect Kussmaul respirations as compensation.
Metabolic alkalosis = vomiting, NG suction, excess antacids or diuretics — replace fluid and electrolytes.
A normal pH with abnormal CO2 and HCO3 in opposite directions = full compensation; identify the primary problem by which side matches the pH's lean.
Medical Emergencies You Must Recognize
MI: chest pressure radiating to arm/jaw, diaphoresis, nausea — women and diabetics present atypically (fatigue, dyspnea, epigastric pain). Act: 12-lead ECG, aspirin (chewed), oxygen if hypoxic, nitroglycerin per orders, troponins, reperfusion fast.
Stroke: BE-FAST (Balance, Eyes, Face, Arm, Speech, Time). Get last-known-well time, stat CT before any anticoagulant/thrombolytic; thrombolytics only for ischemic stroke within the window and no exclusions.
Anaphylaxis: stridor, hypotension, hives after exposure — epinephrine IM first, then airway support, fluids, antihistamines/steroids.
DKA (usually type 1): glucose >250, ketones, Kussmaul breathing, fruity breath, dehydration — fluids FIRST, then insulin infusion; watch potassium fall as insulin drives K+ into cells. HHS (type 2): glucose often >600, profound dehydration, no significant ketosis.
Autonomic dysreflexia (spinal cord injury T6 or above): pounding headache, hypertension, flushing above the lesion — sit the client up FIRST, then find and remove the trigger (full bladder is most common).
Increased intracranial pressure: earliest sign is decreased level of consciousness; late — Cushing triad (widened pulse pressure, bradycardia, irregular respirations). HOB 30°, midline head, avoid clustering care, treat fever and pain.
Chronic Condition Management
Heart failure: daily weights (report 2–3 lb/day or 5 lb/week gain), sodium restriction, diuretics (watch K+), ACE/ARB + beta blocker backbone; left HF = lungs (crackles, orthopnea), right HF = body (JVD, edema, hepatomegaly).
COPD: pursed-lip breathing, bronchodilators before inhaled steroids, rinse mouth after steroid inhalers, titrate oxygen to prescribed target (commonly 88–92%), highest-calorie small meals, flu/pneumonia vaccines.
CKD/dialysis: no BP/venipuncture in the fistula arm, assess thrill and bruit every shift, hold dialyzable meds pre-dialysis per orders, restrict K+/phosphorus/fluid, daily weights.
Cirrhosis: monitor for bleeding (varices — report hematemesis immediately), ascites (paracentesis care), and encephalopathy (asterixis, confusion — lactulose to 2–3 stools/day).
Diabetes sick-day rules: never stop insulin, check glucose and ketones more often, keep drinking fluids, call the provider for persistent vomiting or moderate/large ketones.
Asthma: know the personal best peak flow — green ≥80%, yellow 50–79% (rescue inhaler, follow plan), red <50% (rescue + emergency care). Rescue = short-acting beta agonist; controllers are daily, never for acute attacks.
Ventilators, Chest Tubes, and Trachs
Ventilator alarms: HIGH pressure = obstruction (secretions — suction; kink; biting; coughing). LOW pressure = disconnection or leak. If the cause is not found immediately, bag the client manually with 100% O2 and get help — never silence and walk away.
Chest tubes: tidaling in the water seal is normal; continuous bubbling in the water seal = air leak (check connections); gentle bubbling in suction control is expected. Keep the system below the chest; do not strip/milk tubes; if the tube pulls out of the client, cover with petroleum gauze taped on three sides; if the system breaks, place the tube in sterile water.
Tracheostomy: keep the obturator and a spare trach (same size and one smaller) at the bedside; suction ≤10–15 seconds with sterile technique, pre-oxygenate; if decannulated in the first days, call for help and ventilate as trained.
Suctioning rules: apply suction only on withdrawal, limit passes, reoxygenate between passes; bradycardia during suctioning = vagal stimulation — stop and oxygenate.
Post-CVA swallowing: keep NPO until formally screened; aspiration pneumonia is the killer complication.
Endotracheal tube care: verify placement (end-tidal CO2, bilateral breath sounds), secure, note lip-line depth, HOB 30–45° and oral care per VAP bundle.
Practice Questions
Answer each question, then read the rationale — the rationale is where the learning happens.
1.ABG results: pH 7.30, PaCO2 38, HCO3 18. How should the nurse interpret these values?
Rationale: pH 7.30 is acidotic. CO2 is normal, but HCO3 is low (18) — the metabolic side matches the acidotic pH (ROME: metabolic equal). CO2 has not yet shifted, so it is uncompensated metabolic acidosis — think DKA, renal failure, or severe diarrhea.
2.A client with a T4 spinal cord injury suddenly reports a pounding headache. BP is 210/110 with flushing above the injury level. What should the nurse do FIRST?
Rationale: This is autonomic dysreflexia. Sitting the client upright uses orthostatic pooling to drop the BP immediately, then remove the trigger — a full bladder or kinked catheter is the most common cause. Lying flat worsens the hypertension; medication comes if the trigger search fails.
3.The high-pressure alarm on a ventilator sounds repeatedly. The client is coughing and secretions are visible in the tube. What should the nurse do?
Rationale: High-pressure alarms signal obstruction — here, visible secretions with coughing. Suctioning clears the cause. Silencing without fixing, raising the limit, or extubating all endanger the client.
4.The nurse assesses a client's chest tube and notes continuous vigorous bubbling in the water-seal chamber. What does this indicate?
Rationale: The water seal should show gentle tidaling with respirations; continuous bubbling there means air is leaking into the system — check every connection from dressing to device and notify the provider if the leak persists. Gentle continuous bubbling is normal only in the suction control chamber.
5.A client with DKA has a glucose of 480 mg/dL, pH 7.18, and deep rapid respirations. Which order should the nurse implement FIRST?
Rationale: DKA management starts with aggressive isotonic fluid resuscitation — these clients are profoundly dehydrated. Insulin follows fluids (and requires a safe potassium level first). Bicarbonate is rarely used, and potassium is NEVER given IV push.
6.A client with heart failure gained 3 pounds since yesterday and reports new orthopnea. Crackles are audible bilaterally. Which prescription should the nurse administer FIRST?
Rationale: Rapid weight gain, orthopnea, and crackles indicate acute fluid overload — the loop diuretic addresses the emergency. Potassium follows diuresis monitoring, and a beta blocker may worsen acute decompensation; verify parameters before giving.