Too Big, Too Small or Just Right? Why the 28 French Chest Tube Is the Best Size

Area of Science:

• Medical Devices
• Fluid Dynamics
• Trauma Surgery

Background:

• Tube thoracostomy is crucial for trauma patients, but optimal chest tube size remains undetermined.
• This study investigates chest tube drainage efficiency in a controlled laboratory setting.
• Flow rates are compared against predictions from the Hagen-Poiseuille equation.

Purpose of the Study:

• To determine the optimal chest tube size for drainage in trauma patients.
• To compare measured chest tube flow rates with predicted rates using the Hagen-Poiseuille equation.
• To evaluate the impact of thoracostomy opening size on flow rates for different chest tube sizes.

Main Methods:

• A massive hemothorax model was created using a synthetic blood substitute and a Pleur-evac system.
• Chest tube sizes 20F, 24F, 28F, 32F, and 36F were tested.
• Flow rates were measured by timing the drainage of 2L of fluid, with thoracostomy opening size varied from 2 to 12 mm.

Main Results:

• All tubes occluded at a 2 mm opening; 32F and 36F occluded at 3 mm.
• 28F and larger tubes maintained high, consistent flow rates down to a 7 mm opening.
• Maximum flow rates ranged from 21.7 mL/s (20F) to 61.0 mL/s (36F), with diminishing incremental increases for larger tubes.

Conclusions:

• The 28F chest tube demonstrated high, consistent flow and velocity, outperforming smaller tubes.
• Larger chest tubes (32F, 36F) offered only marginal flow rate increases.
• The 28F tube represents an optimal balance of size and flow rate for clinical applications in trauma.