sepsis after hip replacement - Nursing Case Study
Pathophysiology
• Primary mechanism: Bacterial invasion occurs at the surgical site during or after hip replacement, leading to a localized infection. The body's immune response attempts to eliminate the bacteria, causing an inflammatory reaction.
• Secondary mechanism: The inflammatory response triggers the release of pro-inflammatory cytokines into the bloodstream, potentially leading to systemic inflammation. This systemic inflammatory response can cause widespread vasodilation and increased capillary permeability.
• Key complication: The systemic inflammatory response may progress to sepsis, characterized by organ dysfunction due to inadequate blood flow and oxygenation. Early recognition and intervention are crucial to prevent severe complications such as septic shock or multi-organ failure.
Patient Profile
Demographics:
68-year-old female, retired school teacher
History:
• Key past medical history: Hypertension, Type 2 Diabetes, Osteoarthritis
• Current medications: Lisinopril, Metformin, Ibuprofen
• Allergies: Penicillin
Current Presentation:
• Chief complaint: Fever and increased pain at surgical site
• Key symptoms: Fever, chills, increased heart rate, confusion, redness and warmth around hip incision
• Vital signs: Temperature 102.5°F, Heart rate 115 bpm, Blood pressure 88/56 mmHg, Respiratory rate 24 breaths per minute
Section 1
New Diagnostic Results:
Following the initial assessment, the healthcare team ordered a series of diagnostic tests to confirm the suspicion of sepsis and guide further management. Blood cultures were obtained to identify the causative organism, while a complete blood count (CBC) revealed leukocytosis with a white blood cell count of 18,000/mm³, indicating an active infection. Additionally, elevated C-reactive protein (CRP) and procalcitonin levels suggested a significant inflammatory response. A lactate level was drawn and found to be elevated at 3.2 mmol/L, raising concerns about tissue hypoperfusion and the potential progression toward septic shock.
Further imaging, including an ultrasound of the hip, revealed a localized fluid collection adjacent to the prosthesis, consistent with a possible abscess formation. This finding, coupled with the patient's worsening clinical picture, indicated the likelihood of a deep surgical site infection. Given the patient's allergy to penicillin, the medical team considered alternative antibiotic regimens that would effectively cover a broad spectrum of potential pathogens, including Gram-positive and Gram-negative bacteria.
These diagnostic results necessitated a prompt and targeted intervention plan to address both the local infection and the systemic inflammatory response. The next steps would involve initiating broad-spectrum intravenous antibiotics, considering surgical consultation for possible drainage of the abscess, and closely monitoring the patient's hemodynamic status to prevent further deterioration. These measures aim to stabilize the patient and prevent the escalation to septic shock, while the healthcare team remains vigilant for any new complications that may arise.
Section 2
Change in Patient Status:
Despite the initiation of broad-spectrum intravenous antibiotics, the patient's condition began to show signs of deterioration over the next 24 hours. The patient developed a fever of 39.5°C (103.1°F), and her heart rate increased to 120 beats per minute, indicating a systemic response to the ongoing infection. Blood pressure readings fluctuated, with the systolic pressure dropping to 85 mmHg, raising concerns about potential progression to septic shock. The patient's respiratory rate increased to 28 breaths per minute, accompanied by shallow breathing, suggesting respiratory distress possibly due to metabolic acidosis or the body's attempt to compensate for hypoperfusion.
In light of these changes, the healthcare team performed a repeat lactate measurement, which showed a further increase to 4.5 mmol/L, reinforcing the concern for worsening tissue hypoxia. Additionally, a repeat CBC indicated persistent leukocytosis, now accompanied by a shift to the left with an increased band count. The patient's mental status also began to decline, with confusion and disorientation noted during the nursing assessment, a possible indication of encephalopathy secondary to sepsis.
Given these developments, the medical team prioritized fluid resuscitation to address hypotension and improve perfusion. Continuous hemodynamic monitoring was initiated, and vasopressor support was considered should the patient's blood pressure fail to respond adequately to fluid therapy. A surgical consultation was expedited to evaluate the need for urgent drainage of the suspected abscess. The team recognized the need for rapid intervention to stabilize the patient’s condition and prevent further progression to multi-organ dysfunction. The evolving clinical picture necessitated close monitoring and frequent reassessment, with a focus on identifying and managing any additional complications that might arise in this critical phase of care.
Section 3
Response to Interventions:
Following the initiation of aggressive fluid resuscitation, the patient's blood pressure showed a slight improvement, with systolic readings rising to 95 mmHg. However, despite these efforts, the patient remained tachycardic with a heart rate persisting at 115 beats per minute. The respiratory rate continued to be elevated at 26 breaths per minute, and the patient exhibited signs of increased work of breathing. Oxygen saturation dropped to 88% on room air, necessitating supplemental oxygen to maintain adequate oxygenation. The healthcare team decided to initiate low-dose norepinephrine infusion to support blood pressure and improve systemic perfusion.
In response to the vasopressor therapy, the patient's perfusion status showed modest improvement, as evidenced by a slight increase in urine output to 30 mL/hour. Mental status, however, remained impaired, with continued confusion and disorientation. Repeat arterial blood gas analysis indicated a persistent metabolic acidosis, with a pH of 7.28 and a bicarbonate level of 18 mmol/L, suggesting ongoing tissue hypoperfusion and the need for further intervention.
Despite the initial response to fluid and vasopressor therapy, the patient's clinical condition remained precarious, prompting the healthcare team to escalate the evaluation for potential sources of infection. A CT scan of the hip revealed a fluid collection suggestive of an abscess, reinforcing the need for an urgent surgical intervention. Given the patient's continued instability, discussions were held with the surgical team to coordinate a drainage procedure, while the nursing team remained vigilant in monitoring the patient's vital signs and organ function, understanding that any further delay could exacerbate the risk of multi-organ dysfunction syndrome.
Section 4
As the surgical team prepared for the drainage procedure, the patient's condition began to evolve with new complications. Despite the norepinephrine infusion, blood pressure readings fluctuated, dropping occasionally to systolic levels of 85 mmHg, indicating potential refractory shock. The nursing team noted an increase in the patient's respiratory distress, characterized by accessory muscle use and shallow breathing. The respiratory rate escalated to 32 breaths per minute, and oxygen saturation struggled to remain above 90% even with high-flow oxygen therapy. This prompted a rapid response from the critical care team, who initiated non-invasive ventilation to support the patient's respiratory function.
Laboratory results returned with concerning trends; the white blood cell count had risen to 20,000 cells/mm³, and a repeat blood culture was positive for gram-negative bacilli, suggesting a possible bloodstream infection secondary to the suspected abscess. Additionally, the lactate level remained elevated at 4.5 mmol/L, further indicating ongoing tissue hypoperfusion and metabolic stress. The nursing team collaborated closely with the infectious disease specialists to adjust the antimicrobial regimen, incorporating broad-spectrum antibiotics to cover potential pathogens.
Despite these interventions, the patient's mental status continued to decline, with increased confusion and lethargy. The healthcare team recognized signs of potential acute kidney injury, as evidenced by a rise in serum creatinine to 2.1 mg/dL from a baseline of 1.0 mg/dL, coupled with oliguria despite ongoing fluid resuscitation. These developments necessitated a multidisciplinary approach, with nephrology consulted to evaluate renal support options. The patient's critical status underscored the urgency of the planned surgical intervention to address the identified abscess, aiming to stabilize the source of infection and mitigate further systemic deterioration.
Section 5
As the team prepared to transport the patient for the drainage procedure, a new complication emerged that required immediate attention. The patient's cardiac monitor began to show frequent premature ventricular contractions (PVCs), which progressed to a short run of ventricular tachycardia. This prompted an urgent reassessment by the critical care team to evaluate potential cardiac involvement or electrolyte imbalances contributing to the arrhythmias. A stat electrolyte panel revealed significant hypokalemia, with a serum potassium level of 2.8 mmol/L, likely exacerbated by ongoing high-dose diuretic therapy used to manage fluid overload and support renal function.
Recognizing the urgency of correcting the electrolyte imbalance, the nursing team initiated intravenous potassium replacement while closely monitoring cardiac rhythm and serum potassium levels. Concurrently, the patient's renal function continued to decline, with serum creatinine rising to 2.7 mg/dL and urine output decreasing to less than 20 mL/hour. These findings indicated a progression of acute kidney injury, necessitating an expedited review by the nephrology team to discuss potential renal replacement therapy if conservative measures failed to stabilize renal function.
The interdisciplinary team, comprising critical care, infectious disease, nephrology, and surgical specialists, convened to reassess the treatment plan. The priority remained to stabilize the patient's hemodynamic status and address the underlying infection source through surgical intervention. However, the onset of cardiac instability and worsening renal function added layers of complexity to the patient's condition, requiring vigilant monitoring and dynamic adjustment of therapeutic strategies. The team remained committed to a comprehensive approach, balancing the immediate need for source control with the management of emerging complications to optimize the patient's chances for recovery.