sepsis - Nursing Case Study

Pathophysiology

• Primary mechanism: Sepsis begins with an infection that triggers a systemic inflammatory response syndrome (SIRS). This response often results in fever, increased heart rate and respiratory rate.

• Secondary mechanism: The immune system's response to the infection can become overactive, leading to widespread inflammation and blood clotting. This can cause decreased blood flow and oxygen to vital organs, leading to organ failure.

• Key complication: If not treated promptly, sepsis can progress to septic shock - a severe condition that causes a significant drop in blood pressure and may lead to death. Other possible complications include acute respiratory distress syndrome (ARDS) and multiple organ dysfunction syndrome (MODS).

Patient Profile

Demographics:

67-year-old male, retired construction worker

History:

• Key past medical history: Type 2 Diabetes Mellitus, Chronic Obstructive Pulmonary Disease (COPD), Hypertension

• Current medications: Metformin, Salbutamol Inhaler, Lisinopril

• Allergies: Penicillin

Current Presentation:

• Chief complaint: High fever, confusion, shortness of breath

• Key symptoms: Rapid breathing, increased heart rate, feeling very sick, changes in mental state, decreased urine output

• Vital signs: Temperature 39.5°C (103.1°F), Heart rate 120 beats per minute, Respiratory rate 30 breaths per minute, Blood pressure 90/55 mmHg, Oxygen saturation 88% on room air.

Section 1

New Diagnostic Results:

Upon admission, the patient's blood tests reveal a white blood cell count of 22,000 cells/mL, suggesting a severe infection. Blood cultures are sent to the lab immediately to identify the possible source of infection. The patient's arterial blood gas (ABG) shows a pH of 7.29, PaCO2 of 50 mmHg, and PaO2 of 55 mmHg, indicating respiratory acidosis, likely secondary to his underlying COPD and the systemic inflammation caused by sepsis. His lactate level is elevated at 4.5 mmol/L, signaling potential tissue hypoperfusion.

The patient's chest X-ray shows bilateral infiltrates, suggesting the presence of pneumonia, which could be the source of the sepsis. Additionally, the patient's HbA1c is 9.0%, indicating poorly controlled diabetes which might have also contributed to his heightened risk for infections. Given the patient’s known allergy to Penicillin, the healthcare team has to be cautious while selecting the appropriate broad-spectrum antibiotic until the results of the blood culture are available. These results necessitate prompt intervention to halt the progression of sepsis and prevent further organ damage.

Section 2

Change in Patient Status:

Over the next 12 hours, the patient's condition begins to deteriorate. His blood pressure drops to 90/50 mmHg, and his heart rate increases to 110 beats per minute, signs of hemodynamic instability likely due to the sepsis. His oxygen saturation falls to 88% on 2 liters of nasal cannula oxygen and his respiratory rate increases to 26 breaths per minute, indicating worsening respiratory distress. His Glasgow Coma Scale score decreases to 13/15, reflecting altered mental status.

Furthermore, his urine output decreases to less than 0.5 mL/kg/hr, suggesting possible acute kidney injury secondary to septic shock, a severe complication of sepsis. Repeat blood tests indicate worsening leukocytosis with a white blood cell count now at 25,000 cells/mL, and rising lactate levels at 5.2 mmol/L, further evidence of progressing sepsis and tissue hypoperfusion. These changes in the patient's condition necessitate immediate reassessment and modification of the treatment plan.

Section 3

New Diagnostic Results:

As the patient's condition continues to deteriorate, additional laboratory tests are ordered to further assess his condition. A blood gas reveals a pH of 7.28, PaCO2 of 55, and HCO3 of 22, indicating respiratory acidosis, likely due to hypoventilation from increased work of breathing. Blood cultures are positive for gram-negative bacilli, confirming a bacterial source for the sepsis, and antibiotic sensitivity tests indicate the organism is sensitive to meropenem.

A renal panel shows elevated creatinine levels at 2.8 mg/dL and BUN at 35, confirming the suspicion of acute kidney injury. His platelet count has dropped to 90,000 cells/mL, suggesting developing disseminated intravascular coagulation (DIC), a serious complication of sepsis that can lead to multi-organ failure. The new findings necessitate urgent intervention to prevent further deterioration and organ damage. The patient is started on meropenem, and the primary care team is consulted for possible dialysis. It's crucial to keep monitoring the patient's vital signs and laboratory values to evaluate the effectiveness of these interventions and to catch any potential new complications early.

Section 4

Change in Patient Status:

Over the next 24 hours, the patient's condition continues to deteriorate. Despite the administration of meropenem, his fever escalates to 39.5°C and he remains tachycardic at 120 beats per minute. His respiratory rate increases to 30 breaths per minute, and his blood pressure drops to 90/60 mmHg, suggesting ongoing septic shock. His oxygen saturation dips to 88% on room air, indicating worsening respiratory distress. The patient is clearly in distress, appearing anxious and disoriented.

In response to the deteriorating condition, the nurse notifies the primary care team and intensivist. The decision is made to intubate the patient and start mechanical ventilation to manage his respiratory failure. His vital signs and acid-base imbalance need to be continuously monitored to assess the effectiveness of the interventions and determine the next steps in his management. The nurse also prepares the patient for possible dialysis, as his renal function continues to decline. The current situation demands close monitoring, prompt clinical reasoning, and swift intervention to prevent further complications.

Section 5

New Diagnostic Results:

The latest laboratory results are alarming. The patient's white blood cell count has risen to 22,000 cells/mcL, indicating worsening infection. Blood cultures reveal gram-negative bacilli, confirming the presence of a bacterial infection. His serum creatinine level has escalated to 3.2 mg/dL and his blood urea nitrogen has spiked to 45 mg/dL, suggesting rapidly declining renal function. The arterial blood gas analysis shows a pH of 7.28, a PaCO2 of 30 mmHg, a PaO2 of 72 mmHg, and a bicarbonate level of 15 mEq/L, indicative of a mixed respiratory and metabolic acidosis.

These results confirm the diagnosis of sepsis, with acute respiratory distress syndrome (ARDS) and acute kidney injury (AKI). The nurse quickly recognizes the need to escalate care and intervention, including the need for renal replacement therapy. The primary care team and intensivist are promptly updated about the new findings. Clinical reasoning suggests the need for additional interventions, such as the use of vasopressors to manage his hypotension, and the need to reassess the antibiotic regimen considering the blood culture results. The nurse prepares to monitor the patient's response to these interventions closely while also anticipating potential complications such as multi-organ failure.