kidney stone - Nursing Case Study
Pathophysiology
• Primary mechanism: Supersaturation of urine with stone-forming substances such as calcium, oxalate, and uric acid leads to the crystallization process. These crystals aggregate to form stones, especially when urine volume is low or when there's an imbalance in promoters and inhibitors of crystal formation.
• Secondary mechanism: Impaired renal tubular handling of minerals, often due to genetic predispositions or dietary factors, can exacerbate the concentration of stone-forming substances. This may include hypercalciuria, hyperoxaluria, or hypocitraturia, disturbing the normal balance and promoting stone formation.
• Key complication: Obstruction of the urinary tract can occur as stones migrate, leading to acute pain, potential infection, or renal impairment due to increased pressure and reduced kidney function. This is clinically relevant as it requires prompt intervention to prevent kidney damage.
Patient Profile
Demographics:
42-year-old male, construction worker
History:
• Key past medical history: Hypertension, history of recurrent urinary tract infections
• Current medications: Lisinopril 10 mg daily, Ibuprofen as needed for pain
• Allergies: Penicillin
Current Presentation:
• Chief complaint: Severe flank pain and difficulty urinating
• Key symptoms: Nausea, hematuria, fever, chills
• Vital signs: Blood pressure 150/95 mmHg, heart rate 110 bpm, temperature 101.3°F, respiratory rate 18 breaths per minute
Section 1
As the healthcare team conducts an initial assessment, the patient's presentation becomes more concerning. The physical examination reveals costovertebral angle tenderness on the right side, consistent with renal colic. Lab tests show elevated white blood cell count at 18,000/mm³, indicating a possible infection, and serum creatinine levels have risen to 1.8 mg/dL from a baseline of 1.0 mg/dL, suggesting impaired kidney function. Urinalysis is significant for elevated red blood cells and white blood cells, further supporting the presence of hematuria and infection. Additionally, a CT scan without contrast identifies a 6mm stone located in the right ureter, causing partial obstruction and hydronephrosis.
Given the patient's symptoms and lab findings, the likelihood of a developing urinary tract infection secondary to urinary stasis from the obstructing stone is high. The fever and elevated heart rate suggest a systemic response, possibly sepsis, necessitating prompt intervention. The patient's hypertension, combined with rising creatinine levels, signals that renal perfusion may already be compromised, requiring careful management of blood pressure. The team considers initiating intravenous fluids to improve hydration and renal perfusion, alongside antibiotics to address the infection.
As the patient remains in significant pain despite ibuprofen, the decision is made to administer IV opioids for better pain control. The plan includes consulting urology for potential intervention to relieve the obstruction if spontaneous passage does not occur. This comprehensive approach aims not only to manage the acute symptoms but also to prevent further renal impairment or progression to acute kidney injury, thus setting the stage for the next critical steps in the patient's management.
Section 2
As the healthcare team continues to monitor the patient, new developments in the clinical picture arise. Approximately 12 hours after the administration of IV fluids and antibiotics, the patient's vital signs show a concerning change. The patient's heart rate, previously elevated at 110 beats per minute, has now increased to 125 beats per minute. Blood pressure remains elevated at 150/95 mmHg, and the patient is experiencing persistent tachypnea with a respiratory rate of 24 breaths per minute. The fever, initially controlled with antipyretics, has risen again to 102.5°F (39.2°C), indicating that the infection may not be responding adequately to the initial antibiotic regimen.
Laboratory tests reveal a further increase in serum creatinine to 2.2 mg/dL, suggesting worsening renal function. Additionally, the patient's white blood cell count has climbed to 20,000/mm³, reinforcing the suspicion of a systemic infection. A repeat urinalysis shows persistent hematuria and pyuria, with the presence of nitrites, which is indicative of a gram-negative bacterial infection, possibly complicated by the obstructing ureteral stone. Blood cultures are pending but are expected to provide further insight into the causative organism and guide antibiotic therapy.
In response to these developments, the healthcare team must reassess the current treatment plan. The escalation of the patient's tachycardia and fever, alongside deteriorating renal function, suggests potential progression to urosepsis. Immediate considerations include modifying the antibiotic regimen based on the most likely pathogens and initiating more aggressive fluid resuscitation to support renal perfusion. Additionally, the urgency of urological intervention increases as the risk of acute kidney injury looms larger. The urology team is consulted for possible placement of a ureteral stent or percutaneous nephrostomy to relieve the obstruction and mitigate further complications. This evolving scenario underscores the need for vigilant monitoring and timely reassessment to prevent systemic deterioration and optimize patient outcomes.
Section 3
As the healthcare team continues to monitor the patient, new complications emerge that further challenge the clinical picture. Approximately 24 hours after the initial changes in the patient's condition, blood cultures return positive for Escherichia coli, confirming a gram-negative bacterial infection. This bacterium is known for its resistance to certain antibiotics, prompting the need for a revision of the antibiotic regimen. The infectious disease specialist recommends switching to a broad-spectrum antibiotic with known efficacy against E. coli, such as piperacillin-tazobactam, to address the presumed urosepsis.
Concurrent with this change, the patient's condition shows signs of further deterioration. Despite increased fluid resuscitation efforts, the patient's urine output has decreased significantly, indicating potential acute kidney injury secondary to obstructive uropathy. The urology team, acknowledging the urgency of the situation, prioritizes the patient for an immediate ureteral stent placement. This intervention aims to relieve the obstruction caused by the kidney stone, thereby reducing the back pressure on the kidneys and alleviating the worsening renal impairment.
In the meantime, the patient's vital signs continue to be closely monitored. The heart rate remains elevated at 128 beats per minute, and blood pressure fluctuates around 145/90 mmHg. Oxygen saturation is stable at 95% on room air, but the respiratory rate remains persistently high at 26 breaths per minute, likely due to metabolic acidosis from impaired renal function. As the team awaits the results of the intervention, they remain vigilant for any signs of further complications, including potential septic shock or multi-organ dysfunction. This phase of the patient's journey emphasizes the critical importance of timely interventions and the need for ongoing clinical reasoning to navigate complex, evolving health challenges successfully.
Section 4
As the healthcare team continues to manage the patient's care, new diagnostic results provide further insight into the evolving clinical scenario. The laboratory tests report a significant elevation in the patient's serum creatinine and blood urea nitrogen (BUN) levels, confirming the suspicion of acute kidney injury (AKI). Specifically, the creatinine level has risen to 3.5 mg/dL from a baseline of 1.2 mg/dL, and the BUN is elevated at 48 mg/dL, indicative of renal impairment. Additionally, an arterial blood gas (ABG) test reveals a metabolic acidosis with a pH of 7.29 and a bicarbonate level of 18 mEq/L, corroborating the respiratory compensation suggested by the patient's elevated respiratory rate.
These results prompt the team to reassess the patient's fluid management strategy and electrolyte balance, given the risk of electrolyte imbalances such as hyperkalemia, which could further complicate the patient's condition. Potassium levels are measured at 5.8 mEq/L, warranting immediate attention to prevent cardiac complications. The healthcare team initiates measures to correct the metabolic acidosis and hyperkalemia, including the administration of sodium bicarbonate and calcium gluconate to stabilize cardiac membranes.
In parallel, the patient's response to the revised antibiotic regimen is closely monitored. Within 12 hours of initiating piperacillin-tazobactam, there is a modest improvement in the patient's systemic inflammatory response, as evidenced by a slight reduction in heart rate to 120 beats per minute and stabilization of blood pressure at 140/88 mmHg. However, vigilance remains crucial as the risk of septic shock persists. The multidisciplinary team continues to collaborate, reassessing the patient's response to the ureteral stent placement and the need for potential escalation of care, ensuring that all interventions align with the overarching goal of restoring renal function and resolving the infection.
Section 5
As the healthcare team continues to monitor the patient's progress, a new complication arises in the form of decreased urine output, with the patient producing less than 300 mL over the past 24 hours. This oliguria, in conjunction with the rising creatinine and BUN levels, suggests that the acute kidney injury is progressing towards acute tubular necrosis (ATN), a condition that can significantly impede renal recovery if not addressed promptly. The team conducts a thorough assessment, observing the patient for signs of fluid overload, including jugular vein distention, peripheral edema, and pulmonary crackles. Vital signs reveal a slightly elevated blood pressure of 148/92 mmHg, with the heart rate remaining stable at 116 beats per minute. The patient is experiencing mild dyspnea, raising concerns about potential pulmonary complications secondary to fluid retention.
In response to these findings, the healthcare team revises the fluid management plan, opting for cautious diuresis with intravenous furosemide to facilitate renal perfusion and promote urine output. They also initiate continuous renal replacement therapy (CRRT) as a precautionary measure to support renal function and manage electrolytes effectively. The patient's serum potassium levels are monitored closely, as the diuretic therapy could further alter electrolyte balance. The team remains vigilant for signs of electrolyte shifts, such as muscle weakness or cardiac arrhythmias, which could indicate exacerbated hyperkalemia or hypokalemia.
Throughout this process, the multidisciplinary team emphasizes the importance of ongoing assessment and timely interventions. Regular monitoring of renal function tests and electrolyte panels guides the therapeutic approach, while also providing critical data to evaluate the effectiveness of current interventions. As the patient's condition evolves, the team remains committed to adjusting the care plan to address any new challenges, with the ultimate goal of stabilizing the patient's renal function and preventing long-term complications.