What is the appropriate management for a 44-year-old female with a history of kidney stones, presenting to the emergency room (ER) with severe low back and side pain, difficulty breathing, and a recent history of straining her back, without fever or urinary symptoms?

Emergency Management Protocol for Suspected Kidney Stone with Severe Pain

This patient requires immediate pain control with NSAIDs as first-line therapy, urgent ultrasound imaging to confirm diagnosis and rule out complications, and laboratory workup including urinalysis and serum chemistries to assess for infection or metabolic abnormalities. 1

Immediate Pain Management

• Administer NSAIDs (diclofenac, ibuprofen, or metamizole) as first-line analgesic for renal colic, as they reduce the need for additional analgesia compared to opioids and are more effective for stone-related pain. 1

• Use the lowest effective NSAID dose due to cardiovascular and gastrointestinal risks, and monitor renal function carefully. 1

• Reserve opioids (hydromorphine, pentazocine, or tramadol) as second-line agents only if NSAIDs are contraindicated or inadequate, avoiding pethidine due to high vomiting rates. 1

• Consider antispasmodic medications to augment pain control during acute management. 2

Urgent Diagnostic Workup

Imaging Protocol

• Perform ultrasound as the primary diagnostic tool immediately (sensitivity 45%, specificity 94% for ureteral stones and 88% for renal stones), but do not delay emergency care while awaiting imaging. 1

• Follow ultrasound with non-contrast CT scan if diagnosis remains uncertain or to assess stone location, size, burden, and anatomy - this is the standard modality for acute flank pain after ultrasound. 1

• Low-dose CT provides high diagnostic accuracy (93.1% sensitivity, 96.6% specificity) while reducing radiation exposure. 1

Laboratory Assessment

• Obtain urinalysis with both dipstick and microscopic evaluation to assess urine pH, presence of blood, signs of infection, and crystal identification. 3, 4

• Order serum chemistries including electrolytes, creatinine, uric acid, ionized calcium, sodium, potassium, blood cell count, and C-reactive protein to identify underlying metabolic disorders and assess kidney function. 1, 3

• Obtain urine culture if urinalysis suggests infection (given the absence of fever or urinary symptoms, this may not be immediately necessary but should be considered if pyuria is present). 4

Critical Red Flags Requiring Immediate Intervention

• If purulent urine is encountered during any intervention, immediately abort the procedure, establish drainage (ureteral stent or nephrostomy tube), culture the urine, and continue broad-spectrum antibiotics. 1

• Monitor for signs requiring emergency intervention: fever/infection, severe uncontrolled pain despite treatment, vomiting leading to dehydration, or signs of urinary obstruction. 3

• Patients with solitary kidney or fever require immediate comprehensive evaluation. 1

Initial Conservative Management

• Initiate medical expulsive therapy (MET) with an alpha blocker for uncomplicated distal ureteral stones ≤10 mm if stone is confirmed and no complications are present. 5, 6

• Advise immediate increase in fluid intake and provide instructions to strain urine to catch any passed stones for analysis. 3

• Schedule follow-up imaging within 14 days to monitor stone position and assess for hydronephrosis. 6

Stone Analysis and Follow-up Planning

• Ensure stone material is sent for analysis if/when stone passes or is removed - this is essential for guiding prevention strategies, especially given the patient's history of recurrent stones. 1, 3, 4

• Given the history of kidney stones, this patient is at high risk for recurrence and should be scheduled for comprehensive metabolic evaluation including 24-hour urine collection after the acute episode resolves. 3, 4, 6

Common Pitfalls to Avoid

• Do not use opioids as first-line pain management - NSAIDs are superior for renal colic and reduce the need for additional analgesia. 1

• Do not delay imaging for emergency care, but ultrasound should be performed promptly to guide management decisions. 1

• Do not assume musculoskeletal back strain without imaging confirmation - the history of straining the back does not exclude kidney stone as the primary diagnosis, especially given the patient's stone history and characteristic pain pattern. 3

• Ensure antimicrobial prophylaxis is administered within 60 minutes if any intervention is planned. 1