the condition of a client with metabolic acidosis from an intestinal fistula is not improving. the pulse is 125 beats/min and the bp 84/56 mm hg. abg values are: ph 7.1, hco3- 18 meq/l (18 mmol/l), pco2 57 mm hg (7.58 kpa). what iv medication should the nurse expect to provide next?