Final answer:
The nurse should monitor the client receiving gastric lavage for increased bleeding and hypovolemia.
Step-by-step explanation:
The nurse should monitor the client receiving gastric lavage for increased bleeding and hypovolemia. Gastric lavage is a procedure used to remove substances from the stomach, and it can cause trauma to the gastrointestinal tract, leading to bleeding. Additionally, the removal of gastric contents can result in a loss of fluid, leading to hypovolemia.