PURPOSE: Large infusion of crystalloids may induce acid-base alterations according to their strong ion difference ([ @entity6884 ]). We wanted to prove in vivo, at constant PCO(2), that if the [ @entity6884 ] of the infused crystalloid is equal to baseline plasma @entity3157 , the arterial pH remains unchanged, if lower it decreases, and if higher it increases. METHODS: In 12 @entity1707 , anesthetized and mechanically ventilated at PCO(2)    40 mmHg, 2.2 l of crystalloids with a [ @entity6884 ] similar to (lactated Ringer's 28.3 mEq/l), lower than (normal saline 0 mEq/l), and greater than (rehydrating III 55 mEq/l) baseline @entity3157 (29.22    2.72 mEq/l) were infused for 120 min in randomized sequence. Four hours of wash-out were allowed between the infusions. Every 30 min up to minute 120 we measured blood gases, plasma electrolytes, urinary volume, pH, and electrolytes. Albumin, hemoglobin, and @entity6546 were measured at time 0 and 120 min. RESULTS: Lactated Ringer's maintained arterial pH unchanged (from 7.47    0.06 to 7.47    0.03) despite a plasma dilution around 12%. Normal saline caused a reduction in pH (from 7.49    0.03 to 7.42    0.04) and rehydrating III induced an increase in pH (from 7.46    0.05 to 7.49    0.04). The kidney reacted to the infusion, minimizing the acid-base alterations, by increasing/decreasing the urinary anion gap, primarily by changing @entity1372 and @entity2865 concentrations. Lower urine volume after normal saline infusion was possibly due to its greater osmolarity and @entity2865 concentration as compared to the other solutions. CONCLUSIONS: Results support the hypothesis that at constant PCO(2), pH changes are predictable from the difference between the [ @entity6884 ] of the infused solution and baseline plasma @entity3157 concentration.

In vivo conditioning of acid-base equilibrium by crystalloid solutions: an experimental study on XXXX .

@entity1707 :: ('9823', 'Species') :: ['pigs'] @entity6546 :: ('MESH:D010710', 'Chemical') :: ['phosphates'] @entity2865 :: ('CHEBI:17996', 'Chemical') :: ['chloride'] @entity1372 :: ('MESH:D012964', 'Chemical') :: ['sodium'] @entity3157 :: ('CHEBI:17544', 'Chemical') :: ['bicarbonate'] @entity6884 :: ('MESH:D013398', 'Disease') :: ['SID']
@entity1707 :: (9823,Species) :: ['pigs']
