Is an ultrasound (u/s) and laboratory tests such as sedimentation rate (sed rate) and C-reactive protein (CRP) appropriate for a 53-year-old female with acute onset of left subclavicular pain, which improved with Motrin (ibuprofen)?

From the Guidelines

For a 53-year-old female with acute onset of left subclavicular pain that improved with ibuprofen, ultrasound and inflammatory markers (sedimentation rate and C-reactive protein) are generally not appropriate as first-line diagnostic tests. Initial management should focus on a thorough history and physical examination, with consideration of musculoskeletal causes which are common in this presentation. The improvement with ibuprofen suggests an inflammatory process, possibly musculoskeletal in nature such as costochondritis or muscle strain. If the pain persists despite conservative management with NSAIDs (ibuprofen 400-600mg every 6-8 hours with food), heat application, and rest for 2-3 weeks, then further investigation may be warranted. At that point, plain radiographs would typically precede ultrasound. Inflammatory markers like sed rate and CRP are nonspecific and would be more appropriate if systemic inflammatory conditions, infection, or rheumatologic disorders were suspected based on additional symptoms such as fever, weight loss, or multiple joint involvement, as suggested by the European Standing Committee for International Clinical Studies Including Therapeutics (ESCISIT) 1. The key is to match the diagnostic approach to the clinical presentation, and in this case, the isolated subclavicular pain responding to NSAIDs suggests a more conservative initial approach is appropriate. Some may consider the use of ultrasound in certain clinical scenarios, as outlined in the emergency ultrasound guidelines 1, but for this specific case, it is not the first line of action. The focus should remain on monitoring the patient's response to conservative management and adjusting the diagnostic approach as needed based on the evolution of symptoms.

From the Research

Diagnostic Approach

• The patient's symptoms of acute onset left subclavicular pain, which improved with Motrin (ibuprofen), may suggest an inflammatory or musculoskeletal cause.
• Laboratory tests such as sedimentation rate (sed rate) and C-reactive protein (CRP) can be useful in evaluating inflammation, with CRP being a more sensitive and responsive indicator of inflammation than sed rate 2.
• However, the decision to order these tests should be based on the clinical context and the presence of other symptoms or risk factors.

Imaging Studies

• Ultrasound (u/s) can be a useful diagnostic tool in evaluating subclavicular pain, particularly in cases where large-vessel vasculitis is suspected 3.
• The study found that Doppler sonography (DS) had a high sensitivity in detecting large-vessel vasculitis in the subclavian and axillary arteries, but was less sensitive in other areas such as the abdominal aorta and common femoral artery.
• However, the use of u/s should be guided by the clinical presentation and other diagnostic findings.

Clinical Correlation

• Patient concerns and expectations play a significant role in shaping their experience and satisfaction with care 4.
• Physicians should be aware of these concerns and expectations and address them appropriately to improve patient satisfaction and outcomes.
• In this case, the patient's improvement with Motrin (ibuprofen) suggests that the pain may be related to an inflammatory or musculoskeletal cause, and further evaluation with laboratory tests and imaging studies may be warranted.

Inflammatory Markers

• CRP levels have been shown to be positively correlated with the degree of neovascularization in carotid atherosclerotic plaques, suggesting a potential role in evaluating plaque stability 5.
• However, the clinical significance of this finding in the context of subclavicular pain is unclear, and further study is needed to determine the utility of CRP in this setting.

Ultrasound-Guided Procedures

• Ultrasound-guided vascular access has become a widely accepted practice in critically ill patients, and can be used to guide the insertion of vascular devices such as central venous catheters 6.
• However, the use of u/s in this context is primarily for procedural guidance, rather than diagnostic evaluation of subclavicular pain.