Aclient in the emergency department reports that he has been vomiting excessively for the past 2 days. his arterial blood gas analysis shows a ph of 7.50, partial pressure of arterial carbon dioxide (paco2) of 43 mm hg, partial pressure of arterial oxygen (pao2) of 75 mm hg, and bicarbonate (hco3–) of 42 meq/l. based on these findings, the nurse documents that the client is experiencing which type of acid-base imbalance?