disturbances When no effusion is present, relief of chest pain is best accomplished with antiinflammatory therapy and rest Pleurisy can be significant in some children, and constant aggravation with respiration can be frustrating Use of stronger analgesia may be required, provided comprehensive evaluation has been performed to avoid masking significant illness, and with careful attention to avoiding respiratory depression For patients with increased accumulation of pleural fluid, pain is usually less significant; however, respiratory compromise is more likely Thoracentesis is indicated when fluid accumulation is extensive enough to cause dyspnea (typically moderate- to large-sized effusions) and/or for diagnostic purposes ( Fig 99.7 ) Ultrasound guidance for thoracentesis is often used to facilitate this procedure, particularly with small or loculated effusions Complications of thoracentesis include pneumothorax, hemothorax, reexpansion pulmonary edema, and, rarely, air embolism The recommended technique for thoracentesis is provided in Chapter 130 Procedures , section on Thoracentesis