Hypoplastic Left Heart Syndrome - Nursing Case Study
Pathophysiology
• Primary mechanism: Hypoplastic Left Heart Syndrome (HLHS) is a congenital heart defect where the left side of the heart, including left ventricle, mitral valve, aorta, and aortic valve, is underdeveloped. This impairs the heart's ability to pump oxygen-rich blood to the body.
• Secondary mechanism: To compensate, the right side of the heart pumps blood to the lungs and the rest of the body. However, this causes strain on the right heart and can lead to heart failure.
• Key complication: Without surgical intervention, the patent ductus arteriosus (PDA) closes within the first few days of life, causing a severe decrease in blood flow to the body, leading to cyanosis, cardiac arrest, and potentially death.
Patient Profile
Demographics:
3-year-old male, not applicable occupation
History:
• Diagnosed with Hypoplastic Left Heart Syndrome (HLHS) at birth
• Current medications: Digoxin, Furosemide, Warfarin
• No known allergies
Current Presentation:
• Chief complaint: Parents report child seems lethargic and has decreased appetite
• Key symptoms: Rapid breathing, fatigue, difficulty feeding, cyanosis (bluish color in lips and skin)
• Vital signs: Heart rate - 140 bpm, Respiratory rate - 40 breaths per minute, Oxygen saturation - 85%, Blood pressure - 80/50 mmHg, Temperature - 98.6 F.
Section 1
Change in Patient Status:
Over the next 24 hours, the child's condition appears to further deteriorate. His cyanosis becomes more pronounced, with a notable bluish coloration around the mouth and under the nail beds. His oxygen saturation drops to 80% despite receiving 2 liters of supplemental oxygen via nasal cannula. The child's heart rate also increases to 160 bpm and his respiratory rate climbs to 50 breaths per minute, indicating an increasing strain on his cardiovascular and respiratory systems.
New Complications:
In addition to these changes, the child also begins to exhibit signs of fluid overload, a common complication in patients with heart failure. He gains 1 kg in weight over a 24-hour period, his abdomen becomes distended and there is 2+ pitting edema in his lower extremities. A review of his lab results reveals a sudden increase in his B-type natriuretic peptide (BNP) levels to 800 pg/mL, suggestive of worsening heart failure. His international normalized ratio (INR) is also elevated at 3.5, indicating a higher risk of bleeding due to his Warfarin therapy. These new complications necessitate immediate attention and potential adjustments in his treatment plan.
Section 2
Change in Patient Status:
In spite of the interventions, the child's condition continues to decline over the next few hours. His oxygen saturation remains persistently low at 78% despite an increase in oxygen supplementation to 3 liters via nasal cannula. His respiratory rate further escalates to 60 breaths per minute, with evident retractions and nasal flaring, suggesting worsening respiratory distress. His heart rate remains tachycardic at 160 bpm. His blood pressure starts to drop, with readings now at 70/40 mmHg, indicative of poor cardiac output.
Response to Interventions:
In response to these alarming changes, the medical team decides to escalate his treatment. They initiate diuretic therapy, administering Furosemide to alleviate fluid overload. The child's Warfarin dosage is adjusted to manage his elevated INR and reduce the risk of bleeding. Despite these interventions, his BNP levels continue to rise, reaching 1000 pg/mL. His persistent hypoxia, despite increased oxygen supplementation, necessitates the consideration of a more invasive ventilatory support. The team starts to discuss the possibility of intubation and mechanical ventilation as a next step.
Section 3
New Diagnostic Results:
Further diagnostic studies provide a clearer picture of the child's deteriorating health. His echocardiogram reveals a severe obstruction in the left ventricular outflow tract, compromising blood flow to the systemic circulation. His ejection fraction is noted to be around 35%, a significant decrease from the previous 45%. This finding denotes a failure in the heart's pumping ability, leading to the body's poor perfusion.
In addition, his arterial blood gas (ABG) results show a PaO2 of 50 mmHg, PaCO2 of 60 mmHg, and bicarbonate level of 24 mEq/L, indicating a state of respiratory acidosis. His complete blood count (CBC) results also show a rise in white blood cells, particularly neutrophils, suggestive of an infection.
Change in Patient Status:
With the new diagnostic results and his worsening condition, the child becomes increasingly lethargic and unresponsive to stimuli. His skin turns pale, and his extremities become cool to the touch. His central and peripheral pulses become weak but rapid, suggesting a further decline in cardiac output. Capillary refill time extends to more than 3 seconds. He also begins to exhibit restlessness and irritability, likely due to discomfort or distress. His urine output drops to less than 1 ml/kg/hr, suggesting inadequate renal perfusion. These signs point to a likely case of cardiac failure, and immediate medical intervention becomes crucial to prevent further deterioration.
Section 4
New Complications:
The child's deteriorating health soon gives rise to new complications. He develops a fever, registering a temperature of 38.5 degrees Celsius, suggestive of a systemic infection, possibly sepsis. His respiratory rate increases to 42 breaths per minute, with his oxygen saturation dropping to 88% on room air, indicating respiratory distress and hypoxia. His blood pressure also begins to fluctuate, hitting a low of 70/40 mmHg.
Response to Interventions:
The medical team promptly initiates aggressive management. They start the child on broad-spectrum antibiotics pending culture results, and administer supplemental oxygen via a nasal cannula to counteract the hypoxia. They also commence inotropic support with Dobutamine to improve his cardiac output and monitor his urine output closely. Despite these interventions, the child's condition remains precarious, with only slight improvements in his vital signs. His temperature decreases to 37.8 degrees Celsius, his oxygen saturation improves to 92%, and his blood pressure stabilizes at 90/50 mmHg. However, his urine output remains less than 1 ml/kg/hr, and his lethargy persists, indicating ongoing inadequate perfusion. The child's critical condition necessitates continuous monitoring and adjustment of interventions. These developments present a further opportunity for nurses to exercise their clinical reasoning skills, analyzing the child's responses to the interventions, and planning the next steps in his care.
Section 5
New Diagnostic Results:
The child's blood culture results return after 48 hours, indicating the presence of Staphylococcus aureus, confirming the suspicion of sepsis. Furthermore, the Echocardiogram, performed to evaluate the child's cardiac function, reveals a decreased ejection fraction of 35%, indicating a worsening of his heart failure. His complete blood count shows a high white blood cell count of 18,000 per microliter, further confirming the systemic infection. Moreover, his kidney function tests show an elevated serum creatinine level of 1.2 mg/dL, suggesting possible kidney injury due to decreased perfusion.
Change in Patient Status:
Given the new diagnostic results, the child's status takes a turn for the worse. His oxygen saturation drops further to 85%, his urine output decreases to less than 0.5 ml/kg/hr, and he becomes increasingly lethargic. His blood pressure readings also become more unstable, fluctuating between 90/60 mmHg and 70/40 mmHg. The child's worsening condition necessitates urgent medical intervention and constant reassessments of the care plan. These changes challenge the nursing staff to utilize their clinical reasoning skills to interpret the child's deteriorating vitals and lab results, and to correlate these findings with his overall clinical picture. The goal is to guide the medical team in adjusting the child's management plan and preventing further complications.