What is the typical initial suction pressure used for an adult chest tube?

• A. -50 cm H2O
• B. +20 cm H2O
• C. -20 cm H2O (range typically -15 to -20 cm H2O)
• D. -5 cm H2O

Answer: (C)

Opening with a gentle negative pull on the pleural space helps both remove air or fluid and encourage the lung to re-expand. For an adult chest tube, the standard starting suction is around minus 20 cm H2O, with a common acceptable range from about minus 15 to minus 20 cm H2O. This level provides effective drainage without applying excessive force that could injure lung tissue or the pleura.

Setting suction as high as minus 50 cm H2O is usually too aggressive for an initial setup and can increase the risk of tissue injury or re-expansion problems. Using a positive pressure would not create the suction needed to draw out air or fluid from the pleural space. Conversely, a very small negative pressure like minus 5 cm H2O is often not enough to promote adequate drainage or re-expansion.

Thus, the initial, typical choice is around minus 20 cm H2O, within the -15 to -20 cm H2O range.