A nurse is caring for a 2-week-old infant diagnosed with congenital adrenal hyperplasia (CAH). Which assessment finding requires immediate intervention?
1Weight loss of 50 grams over 24 hours
2Serum sodium level of 138 mEq/L
3Blood pressure of 85/50 mmHg
4Vomiting and lethargy with poor feeding✓ 정답
해설
Vomiting, lethargy, and poor feeding indicate adrenal crisis, a life-threatening emergency requiring immediate IV hydrocortisone and fluid resuscitation. Other findings are less urgent or expected in CAH.
Core Nursing ExplanationKey Concept Analysis: This question assesses the nurse's ability to recognize signs of an Adrenal crisis (Acute adrenal insufficiency) in an infant with Congenital Adrenal Hyperplasia (CAH). CAH is a group of genetic disorders affecting cortisol and often aldosterone production. The most common form (21-hydroxylase deficiency) leads to cortisol deficiency, aldosterone deficiency, and androgen excess. Infants are at high risk for a life-threatening salt-wasting crisis in the first few weeks of life due to severe aldosterone deficiency, leading to hyponatremia, hyperkalemia, dehydration, and shock.
Answer Rationale: Key Point! The combination of Vomiting, lethargy, and poor feeding is the classic triad signaling the onset of an adrenal crisis in a salt-wasting CAH infant. Vomiting leads to further fluid and electrolyte loss, lethargy indicates neurological compromise from hyponatremia and poor perfusion, and poor feeding exacerbates dehydration. This is a medical emergency requiring immediate intervention with IV fluids (normal saline) and IV hydrocortisone to prevent cardiovascular collapse.
Distractor Analysis:
Watch out for confusion! Option ①: A weight loss of 50 grams (about 1.8 oz) in 24 hours in a 2-week-old is concerning and requires monitoring, but it is not the most immediate life-threatening sign compared to the symptom cluster in option ④. It could be a precursor, but the clinical presentation of vomiting/lethargy takes priority.
Option ②: A serum sodium level of 138 mEq/L is within the normal range (approx. 135-145 mEq/L). In salt-wasting CAH, you would expect hyponatremia (e.g., < 130 mEq/L). This value does not indicate an immediate crisis.
Option ③: A blood pressure of 85/50 mmHg may be normal for a 2-week-old infant. Normal BP varies with age and size, but this is not typically a hypotensive reading requiring *immediate* intervention in this context. Hypotension is a late sign of adrenal crisis.
Related Concepts: The priority in pediatric nursing is always ABCs (Airway, Breathing, Circulation) and recognizing signs of shock. For CAH, understanding the pathophysiology of cortisol (stress response, glucose metabolism) and aldosterone (sodium retention, potassium excretion) is crucial. Newborn screening for CAH is standard in many countries to prevent missed diagnoses and crises.
Concept Summary
Concept
Key Points
Congenital Adrenal Hyperplasia (CAH)
Autosomal recessive disorder. 21-hydroxylase deficiency most common. Leads to cortisol +/- aldosterone deficiency, androgen excess.
Salt-Wasting Crisis
Life-threatening emergency in first 2-4 weeks of life. Due to aldosterone deficiency causing hyponatremia, hyperkalemia, dehydration, vomiting, shock.
Immediate Signs (NCLEX Priority)
Vomiting, lethargy, poor feeding. This symptom cluster = adrenal crisis until proven otherwise.
Treatment for Crisis
1. IV access. 2. IV bolus of normal saline. 3. IV hydrocortisone (stress dose). 4. Correct electrolytes.
Long-term Management
Lifelong glucocorticoid (e.g., hydrocortisone) and often mineralocorticoid (fludrocortisone) replacement. Stress dose adjustment during illness.
Side-by-Side Comparison!
Assessment Finding
In CAH Infant
Typical Newborn / Less Urgent
Vomiting + Lethargy
Key Point! RED FLAG for adrenal crisis. Requires immediate intervention.
Isolated spit-up common. Lethargy alone needs assessment but may have other causes (infection).
Weight Loss
Concerning trend; monitor closely. Can be an early sign of poor feeding/dehydration.
Some weight loss after birth is normal (up to 10%). 50g/24h needs follow-up but is not an emergency by itself.
Serum Sodium 138 mEq/L
Normal value. In crisis, expect hyponatremia (< 130).
Normal finding. No action needed based on this alone.
BP 85/50 mmHg
May be normal for age. Hypotension is a late sign of shock in infants.
Likely normal for a 2-week-old. Nurses must know age-appropriate vital signs.
Anatomy, Physiology & Pharmacology PointsPathophysiology: The adrenal cortex produces cortisol (zona fasciculata) and aldosterone (zona glomerulosa). In 21-hydroxylase deficiency, the enzyme block shunts precursors to androgen production, causing virilization in females. The cortisol deficiency impairs the stress response and gluconeogenesis. Aldosterone deficiency causes renal salt-wasting, leading to hyponatremia, hyperkalemia, and volume depletion.
Pharmacology: Hydrocortisone is the drug of choice for replacement and crisis because it has both glucocorticoid and some mineralocorticoid activity. Fludrocortisone is a synthetic mineralocorticoid used for chronic aldosterone replacement. During illness, injury, or surgery, patients must receive stress-dose steroids to prevent crisis.
Memory Tips
Acronym for Crisis Signs: Vomiting, Lethargy, Poor feeding = "Very Lethargic Patient" needs IV fluids & steroids NOW.
Think "SALT" for Salt-wasting crisis: Sodium low, Aldosterone low, Lethargy, Throwing up (vomiting).
High-Frequency NCLEX Topics
NCLEX loves to test priority setting and recognizing medical emergencies. CAH is a classic pediatric endocrine emergency. You must know: 1) The specific symptom cluster that indicates crisis. 2) That treatment is IV fluids and IV hydrocortisone. 3) The importance of lifelong steroid replacement and stress dosing. Questions may combine CAH with fluid/electrolyte imbalances or medication administration.
Watch Out for Question Variations!
Shift from Symptom to Intervention: "The nurse is caring for an infant with CAH who is vomiting and lethargic. What is the priority nursing action?" (Answer: Establish IV access and prepare to administer IV fluids and hydrocortisone as prescribed).
Shift to Medication Teaching: "The mother of a child with CAH asks what to do when her child has a fever. What is the nurse's best response?" (Answer: "Administer an extra dose of hydrocortisone as prescribed for stress and call your healthcare provider.").
Lab Value Focus: "Which lab result would the nurse expect to find in an infant experiencing a salt-wasting crisis?" (Answer: Hyponatremia and Hyperkalemia).
Nursing Clinical Practice GuideClinical Scenario: You are the nurse in the pediatric clinic. A frantic mother brings in her 16-day-old infant, who was diagnosed with CAH via newborn screen. She reports, "He's been vomiting all his formula since yesterday, he's so sleepy I can barely wake him to feed, and he feels cool."
Nursing Intervention Strategy:
1Immediate Assessment (ABCs)Check airway, breathing, circulation. Assess level of consciousness using a pediatric scale. Obtain vital signs, including temperature (risk of hypothermia). Check capillary refill and skin turgor for dehydration.
2Activate Emergency ProtocolThis is not a "wait and see" situation. Alert the physician/provider immediately. Prepare for transfer to the emergency department or inpatient unit.
3Prepare for Interventions* IV Access: Anticipate the need for immediate IV placement (often a priority order). In an infant, this may be an umbilical line or peripheral IV.
* Fluid Resuscitation: Prepare 0.9% Normal Saline (NS) for a bolus (e.g., 20 mL/kg).
* Medication: Have IV hydrocortisone (Solu-Cortef) available. Know the stress dose (typically 50-100 mg/m² or 25-50 mg IV for an infant).
4Ongoing MonitoringContinuous cardiorespiratory monitoring. Strict I&O (Intake and Output). Frequent blood glucose and electrolyte checks.
Patient Safety and Precautions:
* Key Point! Never delay treatment for confirmatory labs in a symptomatic infant. Treat based on clinical presentation.
* Handle the infant gently; they are critically ill and fragile.
* Educate parents before discharge: Recognize crisis signs (vomiting, lethargy, poor feeding), never skip medications, and always administer stress doses during illness, injury, or before procedures.
Nursing Procedure & Medication FlowAdministering IV Hydrocortisone in Adrenal Crisis:
1VerifyConfirm the order (e.g., "Hydrocortisone sodium succinate 25 mg IV STAT").
2PrepareReconstitute the vial as directed. Draw up the exact dose.
3AdministerGive via slow IV push over 2-3 minutes or as per protocol. Flush the line before and after with NS.
4MonitorObserve for any immediate adverse reactions (rare with life-saving dose). Monitor for clinical improvement (increased alertness, improved perfusion, cessation of vomiting).
Fluid Bolus Calculation: For a 4 kg infant, a 20 mL/kg bolus = 80 mL of 0.9% NS. Infuse this over 15-30 minutes, monitoring closely for signs of fluid overload (e.g., increased work of breathing).
A Word from Your Senior Nurse
"Nursing is not just about carrying out physician orders — it's about being the frontline guardian for your patients! In clinical practice, recognizing subtle changes in a patient's vital signs early can prevent deterioration. With this infant, you are the one who hears 'vomiting and lethargy' and your internal alarm bells should scream 'ADRENAL CRISIS!' That immediate recognition and swift action save lives. When studying for your boards, don't just memorize — connect everything to a real patient situation and always ask 'why?' That mindset will not only earn you a great score on the NCLEX but will make you a truly confident, professional nurse!"
Congenital Adrenal Hyperplasia — A group of autosomal recessive genetic disorders characterized by enzyme deficiencies in the adrenal steroid synthesis pathway, most commonly 21-hydroxylase deficiency, leading to cortisol deficiency, potential aldosterone deficiency, and androgen excess.
Adrenal Crisis (Acute Adrenal Insufficiency) — A life-threatening condition of severe cortisol deficiency, often triggered by stress, illness, or trauma. In CAH infants, it manifests as a salt-wasting crisis with vomiting, lethargy, dehydration, hyponatremia, and hyperkalemia.
Salt-Wasting — A form of CAH (and other conditions) characterized by aldosterone deficiency, leading to excessive renal loss of sodium (hyponatremia), retention of potassium (hyperkalemia), and resulting dehydration and hypotension.
Hydrocortisone (Solu-Cortef) — A glucocorticoid medication that also has mineralocorticoid activity. It is the first-line treatment for adrenal crisis (IV) and the standard replacement therapy for cortisol deficiency in CAH.
21-Hydroxylase Deficiency — The most common enzyme defect causing CAH (>90% of cases). It impairs the conversion of 17-hydroxyprogesterone to 11-deoxycortisol, disrupting cortisol and aldosterone synthesis and shunting precursors to androgen production.