infection - Nursing Case Study

Pathophysiology

• Primary mechanism: Invasion and multiplication of pathogens - Bacteria, viruses, fungi, or parasites invade the body and start to multiply. These pathogens can enter through various routes including skin breaks, inhalation, ingestion, or via vectors like mosquitoes.

• Secondary mechanism: Host immune response - The body's immune system recognizes foreign invaders and launches a defense. White blood cells attack and destroy the pathogens. Inflammation, fever, and other symptoms occur as a result of this immunological response.

• Key complication: Sepsis - If the immune response fails to control the infection, it can spread through the bloodstream leading to sepsis. Sepsis is a severe, body-wide response to infection that can lead to organ failure and death.

Patient Profile

Demographics:

42 years old, Male, Bus driver

History:

• Key past medical history: Type 2 diabetes, hypertension

• Current medications: Metformin, Lisinopril

• Allergies: Penicillin, Sulfa drugs

Current Presentation:

• Chief complaint: Persistent fever, cough, shortness of breath

• Key symptoms: Fatigue, loss of appetite, nausea, confusion

• Vital signs: Temperature 102.2°F, Blood Pressure 155/95 mmHg, Heart rate 110 bpm, Respiratory rate 22 breaths per minute, Oxygen saturation 92% on room air.

Section 1

Change in patient status:

Over the next 24 hours, the patient's condition worsens. His fever spikes to 103.5°F, his blood pressure drops to 100/60 mmHg, and his respiratory rate increases to 28 breaths per minute. His skin becomes cool and clammy and he develops a new symptom - abdominal pain. He also becomes increasingly confused and disoriented, occasionally mumbling and unable to answer basic questions. His oxygen saturation drops to 88%, even with supplemental oxygen at 2L/min via nasal cannula. The nurse notes that his urine output has significantly decreased to less than 30 mL/hour.

His elevated heart rate of 130 bpm along with the decrease in blood pressure and increased respiratory rate is suggestive of compensatory mechanisms to maintain cardiac output and oxygenation. The decreased urine output, confusion, and abdominal pain indicate that the infection could be spreading, potentially leading to multi-organ involvement. These changes reflect a possible progression from sepsis to severe sepsis or septic shock, requiring immediate intervention. The nurse promptly informs the healthcare team and prepares for possible escalation of care.

Section 2

New Diagnostic Results:

Laboratory results return, revealing a white blood cell count of 18,000/uL, indicating a severe infection. His lactate level is elevated at 4 mmol/L, further suggesting poor tissue oxygenation. Cultures are not yet available, but the patient's blood sample shows the presence of gram-positive cocci bacteria. Adding to the concern, his creatinine has risen to 2.5 mg/dL from a baseline of 1.0 mg/dL, indicating acute kidney injury, likely due to septic shock and decreased perfusion. The liver function tests also show abnormalities, with elevated AST and ALT levels, likely due to systemic inflammation and reduced liver perfusion.

The patient's arterial blood gas (ABG) results show a pH of 7.28, PaO2 of 76 mm Hg, and PaCO2 of 35 mm Hg, indicative of respiratory and metabolic acidosis. His HCO3 level is low at 18 mEq/L, further confirming metabolic acidosis. These findings suggest that the patient's body is not able to compensate for the severe infection and multi-organ failure is imminent unless aggressive treatment is started. The nurse is worried about the patient's deteriorating condition and communicates the lab results to the healthcare team immediately.

Section 3

Change in Patient Status:

Over the next few hours, the patient's condition continues to deteriorate. His blood pressure drops to 90/60 mmHg, his heart rate increases to 120 beats per minute, and his oxygen saturation dips to 88% on room air. He becomes increasingly lethargic and his skin is cool, clammy, and pale, suggesting decreased perfusion to the tissues. His urine output has also significantly decreased to less than 20 mL/hr, indicating that his kidney function is worsening. On auscultation, the nurse notes crackles in the lower lobes of his lungs, indicative of fluid accumulation due to his worsening septic shock.

The nurse also notices that his Glasgow Coma Scale (GCS) score has dropped to 11 from an initial score of 15, indicative of a reduced level of consciousness. This is a concerning finding as it may indicate a decrease in cerebral perfusion. Additionally, his capillary refill time is prolonged to 4 seconds, further suggesting poor peripheral perfusion. These findings emphasize the severity of the patient's condition and the need for prompt and aggressive interventions. The nurse promptly alerts the healthcare team of the change in the patient's status.

Section 4

New Diagnostic Results:

Upon lab examination, the patient's blood tests reveal a high white blood cell count of 20,000/mm3, indicating an ongoing infection. His blood cultures are positive for gram-negative bacteria, confirming sepsis. His lactate levels have also risen to 5 mmol/L, suggesting increased anaerobic metabolism due to tissue hypoxia. Kidney function tests further reveal elevated serum creatinine levels at 2.5 mg/dL and BUN at 28 mg/dL, indicating acute kidney injury likely secondary to sepsis-induced hypoperfusion.

These results paint a picture of a patient in septic shock with multi-organ dysfunction. The nurse quickly communicates these findings to the healthcare team, emphasizing the need for immediate intervention. The nurse anticipates the need for broad-spectrum antibiotics, fluid resuscitation, and possibly vasopressors to maintain adequate blood pressure and organ perfusion. The nurse also begins preparing for possible intubation considering the patient's deteriorating respiratory status and reduced level of consciousness. This case demands critical thinking, prompt decision making, and collaborative team effort for optimal patient outcomes.

Section 5

Change in Patient Status:

Within a few hours, the patient's condition deteriorates further. His blood pressure drops to 90/55 mmHg despite aggressive fluid resuscitation. His heart rate increases to 130 beats per minute, and his respiratory rate has escalated to 28 breaths per minute. Oxygen saturation falls to 88% on room air, raising concerns for impending respiratory failure. His level of consciousness decreases, and he becomes less responsive to verbal stimuli. His skin becomes cool, clammy, and mottled, indicating poor peripheral perfusion.

The nurse promptly notifies the physician of the patient's deteriorating condition, emphasizing the need for urgent intervention. She prepares for the likelihood of initiating vasopressor therapy to restore and maintain adequate blood pressure. She also anticipates the need for endotracheal intubation and mechanical ventilation considering the patient's worsening respiratory status. This situation demands immediate action, close monitoring, and adjustment of the therapeutic plan based on the patient's responses.

The nurse continues to reassess the patient frequently, monitoring for further changes in vital signs, urine output, and level of consciousness. She also keeps a close eye on the patient's lab results, particularly his renal function and lactate levels, to gauge the severity of his condition and the effectiveness of the interventions. This patient's rapidly changing status challenges the nurse's clinical reasoning skills and the entire healthcare team's ability to respond effectively.