Impact of Pleural Manometry on Chest Discomfort After Therapeutic Thoracentesis

Manometry- Versus Symptom-Guided Large Volume Thoracentesis: a Randomized Controlled Study

This randomized controlled trial attempts to determine whether the measurement of pleural pressures during therapeutic thoracentesis affects the development of chest discomfort after the procedure. During thoracentesis, pleural fluid is drained from the pleural space, resulting in lung expansion. In some cases, the lung is not completely re-expandable, in which case continued drainage results in the development of negative pleural pressures and chest discomfort. Negative pleural pressures may also result in other complications such as re-expansion pulmonary edema and pneumothorax. The identification of negative pleural pressures via manometry during the procedure may lead to a reduction in the complication rate.

PRIMARY OBJECTIVES:

I. To study the impact of pleural manometry on the development of chest discomfort during therapeutic thoracentesis compared to conventional symptom-guided thoracentesis.

OUTLINE: Patients are randomized to 1 of 2 treatment arms.

ARM I: Patients undergo manometry-guided therapeutic thoracentesis.

ARM II: Patients undergo symptom-guided thoracentesis.

Inclusion Criteria:

• Referral to pulmonary or interventional radiology services for large-volume thoracentesis

• Presence of a symptomatic moderate or large free-flowing pleural effusion on the basis of:

  • Chest radiograph: effusion filling >= 1/3 the hemithorax, OR
  • Computed tomography (CT)-scan: maximum anteroposterior (AP) depth of the effusion >= 1/3 of the AP dimension on the axial image superior to the hemidiaphragm, including atelectatic lung completely surrounded by effusion, OR
  • Ultrasound: effusion spanning at least three rib spaces with depth of >= 3 cm

Exclusion Criteria:

• Inability to provide informed consent

• Study subject has any disease or condition that interferes with safe completion of the study including:

  • Coagulopathy, with criteria left at the discretion of the operator
  • Hemodynamic instability with systolic blood pressure < 90 mmHg or heart rate > 120 beats/min, unless deemed to be stable with these values by the attending physicians

• Pleural effusion is smaller than expected on bedside pre-procedure ultrasound

• Referral is for diagnostic thoracentesis only

• Manometry felt to be clinically indicated

• Inability to assume or maintain a seated position for the procedure

• Presence of multiple loculations on bedside pre-procedure ultrasound