Role of electrolyte abnormalities and unmeasured anions in the metabolic acid‐base abnormalities in dogs with parvoviral enteritis

Abstract

Background The strong ion model (SIM) is an alternative paradigm in the characterization of acid‐base disturbances particularly in complex disorders. Hypothesis/Objectives To compare the acid‐base changes in dogs with parvoviral enteritis (PE) using the Henderson‐Hasselbalch (HH) approach, with 2 strong ion approaches. Animals Forty‐four dogs with PE, and 16 age‐matched control dogs. Methods Prospective controlled observational study. Acid‐base status was evaluated using the HH model, Fencl‐Stewart (FS) approach and a validated strong ion model (VDM). The acid‐base changes according to each model were classified and compared. Statistical correlations between pH, CO2, and various SIM variables were performed, as well as between the sum of effects (SOE) of the SIM and the individual variables comprising the SOE. Results The HH model identified acid‐base disorders in 31/44 cases of which 16/31 were mixed with metabolic acidosis and concurrent respiratory alkalosis the most common (10/31). Using the FS approach, metabolic changes were present 36/42 cases, with changes in free water (FW), chloride, and unmeasured anions (UA) being the most prevalent. Both FW and UA correlated well with pH; however, UA were most consistently abnormal in severe acidemia. Similarly to the HH, the VDM detected acid‐base disturbances in 28/44 cases. Major contributors to the acid‐base changes were hyponatremia, hypochloremia, and Atot acidosis because of elevated globulins and increased UA. Conclusions and Clinical Importance Acid‐base changes are common and complex in dogs with PE, and were easier to understand using a SIM paradigm. Increases in UA have not been documented in PE in dogs.

Acid‐base imbalances and the association of blood‐gas variables, electrolytes, and biochemical analytes with outcome in hospitalized calves undergoing abdominal surgery

“…Of relevance is the finding that the simplified strong-ion acid-base abnormalities had a higher sensitivity in detecting an acid-base disorder and therefore more explanatory power than the traditional Henderson-Hasselbalch approach which is in line to numerous previous investigations. [9][10][11]15,20 Stepwise linear regression analysis indicated that plasma L-lactate concentration was the most important predictor of venous blood pH. This was an expected finding based on the high prevalence of hyper-L-lactatemia in this study sample 4,12 that was most likely caused by inadequate oxygen delivery to ischemic gastrointestinal tissues secondary to volvulus, torsion, or luminal distention.…”

“…Of relevance is the finding that the simplified strong‐ion acid‐base abnormalities had a higher sensitivity in detecting an acid‐base disorder and therefore more explanatory power than the traditional Henderson‐Hasselbalch approach which is in line to numerous previous investigations. 9 , 10 , 11 , 15 , 20 …”

“…Also, metabolites such as pyruvate, as observed in cows with abomasal volvulus, 42 or ß‐hydroxybutyrate might have contributed to the USI concentration. Unidentified strong anions are a well‐known feature of critically ill animals and humans 11 , 13 , 43 , 44 , 45 and some studies have documented an association between increased USI concentrations and the presence of endotoxemia, sepsis, and inflammatory cytokines. 46 , 47 , 48 Taken together, the associations of AG to L‐lactate, phosphorus, USI, and pH, likely makes AG a global indicator of tissue hypoxia, acidemia, and hydration status and therefore a clinically useful predictor of a negative postoperative outcome in this multivariable approach.…”

“… 3 , 4 , 5 , 7 , 8 These clinicopathologic changes potentially reflect disease severity, and they are associated with acid‐base derangements that can be demonstrated by application of the strong ion difference approach. 9 , 10 , 11 For these reasons, acid‐base and related physicochemical variables might have clinical utility for predicting the outcome in critically‐ill calves undergoing abdominal surgery.…”

Coagulation Abnormalities in Dogs with Parvoviral Enteritis

“…Venous blood gas revealed metabolic acidosis in eight dogs (89%), with a decrease in electrolytes. Metabolic acidosis, hypokalemia, hyponatremia, and hypochloremia are common findings in dogs with CPE resulting from vomiting and diarrhea [ 44 , 45 , 46 ]. Three dogs presented lactic acidosis, which is consistent with the results of a recent study [ 47 ].…”