Effects of Extra-fascial Interscalene Brachial Plexus Block on Diaphragmatic Function in School-Aged Children

Exclusion Criteria

• •Infection, anatomical deformity, or tumor at the puncture site.
• •Coagulation disorders (INR \> 1.4, platelet count \< 100 × 10⁹/L).
• •History of allergy to local anesthetics (ropivacaine).
• •Severe cardiopulmonary or neurological diseases (e.g., epilepsy, myopathy).
• •Pre-existing ipsilateral phrenic nerve paralysis or Horner syndrome.
• •Preoperative long-term use of analgesics (which may affect efficacy assessment).
• •Parent or child refusal to participate in the study.
• •Emergency surgery or inability to cooperate with assessments (e.g., severe developmental delay).