The OR Nurse Is Setting Up a Water-Seal Chest Drainage $\quad 20 \mathrm{~cm} \mathrm{H}_{2} \mathrm{O}$

The OR nurse is setting up a water-seal chest drainage system for a patient who has just had a thoracotomy. The nurse knows that the amount of suction in the system is determined by the water level. At what suction level should the nurse set the system?

A) $\quad 20 \mathrm{~cm} \mathrm{H}_{2} \mathrm{O}$
B) $\quad 15 \mathrm{~cm} \mathrm{H}_{2} \mathrm{O}$
C) $\quad 10 \mathrm{~cm} \mathrm{H}_{2} \mathrm{O}$
D) $\quad 5 \mathrm{~cm} \mathrm{H}_{2} \mathrm{O}$