Quantitative Physicochemical Analysis of Acid-Base Balance and Clinical Utility of Anion Gap and Strong Ion Gap in 806 Neonatal Calves with Diarrhea

BackgroundAcid-base abnormalities in neonatal diarrheic calves can be assessed by using the Henderson-Hasselbalch equation or the simplified strong ion approach which use the anion gap (AG) or the strong ion gap (SIG) to quantify the concentration of unmeasured strong anions such as d-lactate. Hypothesis/ObjectivesTo determine and compare the clinical utility of AG and SIG in quantifying the unmeasured strong anion charge in neonatal diarrheic calves, and to examine the associations between biochemical findings and acid-base variables by using the simplified strong ion approach. We hypothesized that the SIG provides a more accurate prediction of unmeasured strong anions than the AG. AnimalsEight hundred and six neonatal diarrheic calves admitted to a veterinary teaching hospital. MethodsRetrospective study utilizing clinicopathologic findings extracted from medical records. ResultsHyperphosphatemia was an important predictor of venous blood pH. Serum inorganic phosphorus and plasma d-lactate concentrations accounted for 58% of the variation in venous blood pH and 77% of the variation in AG and SIG. Plasma d- and total lactate concentrations were slightly better correlated with SIG (r(s)=-0.69;-0.78) than to AG (r(s)=0.63;0.74). Conclusions and Clinical ImportanceStrong ion gap is slightly better at quantifying the unmeasured strong anion concentration in neonatal diarrheic calves than AG. Phosphorus concentrations should be included as part of the calculation of A(tot) when applying the simplified strong ion approach to acid-base balance to critically ill animals with hyperphosphatemia

Quantitative Physicochemical Analysis of Acid-Base Balance and Clinical Utility of Anion Gap and Strong Ion Gap in 806 Neonatal Calves with Diarrhea

BackgroundAcid-base abnormalities in neonatal diarrheic calves can be assessed by using the Henderson-Hasselbalch equation or the simplified strong ion approach which use the anion gap (AG) or the strong ion gap (SIG) to quantify the concentration of unmeasured strong anions such as d-lactate. Hypothesis/ObjectivesTo determine and compare the clinical utility of AG and SIG in quantifying the unmeasured strong anion charge in neonatal diarrheic calves, and to examine the associations between biochemical findings and acid-base variables by using the simplified strong ion approach. We hypothesized that the SIG provides a more accurate prediction of unmeasured strong anions than the AG. AnimalsEight hundred and six neonatal diarrheic calves admitted to a veterinary teaching hospital. MethodsRetrospective study utilizing clinicopathologic findings extracted from medical records. ResultsHyperphosphatemia was an important predictor of venous blood pH. Serum inorganic phosphorus and plasma d-lactate concentrations accounted for 58% of the variation in venous blood pH and 77% of the variation in AG and SIG. Plasma d- and total lactate concentrations were slightly better correlated with SIG (r(s)=-0.69;-0.78) than to AG (r(s)=0.63;0.74). Conclusions and Clinical ImportanceStrong ion gap is slightly better at quantifying the unmeasured strong anion concentration in neonatal diarrheic calves than AG. Phosphorus concentrations should be included as part of the calculation of A(tot) when applying the simplified strong ion approach to acid-base balance to critically ill animals with hyperphosphatemia

Additive prognostic value of preoperative plasma glucose concentrations in calves undergoing abdominal surgery.

Surgical abdominal emergencies in calves are associated with a guarded prognosis, especially if neonates are affected. Because hypoglycemia has been associated with sepsis and endotoxemia, this study aimed to assess the prognostic relevance of preoperative plasma glucose concentrations (GLUC) in calves requiring surgery for an acute abdominal disorder. For this purpose, data from retrospective and prospective case series were analyzed, consisting of 586 and 83 hospitalized calves, respectively. The outcomes of calves were evaluated until hospital discharge (both study populations) and for 3 mo following discharge by a phone call to the farmer (prospective study population). For the retrospective study population, the overall survival rate was 31.2%. Calves with a negative outcome (NO) had significantly lower median GLUC (4.3 mmol/L) than calves with a positive outcome (PO; 5.0 mmol/L). The survival rates of calves with GLUC 8.84 mmol/L), and GLUC <4.4 mmol/L (age 7-20 d) and <3.3 mmol/L (age ≥21 d), respectively. The area under the receiver operating characteristic curve of this model was 0.79 (95% confidence interval: 0.76-0.83) and the resulting sensitivity and specificity for NO at the optimal probability cut-point of 0.69 were 66.7 and 85.8%, respectively. For the prospective study population, the established model had sensitivity and specificity for predicting NO after 3 mo (proportion 24%) of 61.9 and 85%, respectively. In both study populations, hypoglycemia was significantly associated with intraoperative evidence of a septic process within the abdominal cavity. The present analyses show that hypoglycemia was highly indicative of a poor prognosis and serious intraoperative findings such as peritonitis. Determination of GLUC should therefore be part of the diagnostic work-up in calves suffering from an acute abdominal emergency

Risk Factors for the Development of Hypokalemia in Neonatal Diarrheic Calves

BackgroundNeonatal diarrheic calves have a clear negative potassium balance because of intestinal losses and decreased milk intake but in the presence of acidemia, they usually show normokalemic or hyperkalemic plasma concentrations. ObjectivesTo assess whether marked hypokalemia occurs in response to the correction of acidemia and dehydration and to identify factors that are associated with this condition. AnimalsEighty-three calves with a clinical diagnosis of neonatal diarrhea. MethodsProspective cohort study. Calves were treated according to a clinical protocol using an oral electrolyte solution and commercially available packages of 8.4% sodium bicarbonate, 0.9% saline and 40% dextrose infusion solutions. ResultsThe proportion of hypokalemic calves after 24hours of treatment (19.3%) was twice as great as it was on admission to the hospital. Plasma K+ after 24hours of treatment was not significantly correlated to venous blood pH values at the same time but positively correlated to venous blood pH values on admission (r=0.51, P<.001). Base excess on admission (Odds ratio [OR]=0.81, 95% confidence interval [CI]=0.70-0.94),duration of diarrhea (OR=1.37, 95% CI=1.05-1.80),milk intake during hospitalization (OR=0.54, 95% CI=0.37-0.79) and plasma sodium concentrations after 24hours (OR=1.12, 95% CI=1.01-1.25) were identified to be independently associated (P<.05) with a hypokalemic state after 24hours of treatment. Conclusions and Clinical ImportanceFindings of this study suggest that marked depletion of body potassium stores is evident in diarrheic calves that suffered from marked metabolic acidosis, have a low milk intake and a long history of diarrhea

Effects of Alkalinization and Rehydration on Plasma Potassium Concentrations in Neonatal Calves with Diarrhea

BackgroundIncreased plasma potassium concentrations (K+) in neonatal calves with diarrhea are associated with acidemia and severe clinical dehydration and are therefore usually corrected by intravenous administration of fluids containing sodium bicarbonate. ObjectivesTo identify clinical and laboratory variables that are associated with changes of plasma K+ during the course of treatment and to document the plasma potassium-lowering effect of hypertonic (8.4%) sodium bicarbonate solutions. AnimalsSeventy-one neonatal diarrheic calves. MethodsProspective cohort study. Calves were treated according to a clinical protocol using an oral electrolyte solution and commercially available packages of 8.4% sodium bicarbonate (250-750mmol),0.9% saline (5-10L),and 40% dextrose (0.5L) infusion solutions. ResultsInfusions with 8.4% sodium bicarbonate solutions in an amount of 250-750mmol had an immediate and sustained plasma potassium-lowering effect. One hour after the end of such infusions or the start of a sodium bicarbonate containing constant drip infusion, changes of plasma K+ were most closely correlated to changes of venous blood pH, plasma sodium concentrations and plasma volume (r=-0.73,-0.57,-0.53;P<.001). Changes of plasma K+ during the subsequent 23hours were associated with changes of venous blood pH, clinical hydration status (enophthalmos) and serum creatinine concentrations (r=-0.71, 0.63, 0.62;P<.001). Conclusions and Clinical ImportanceThis study emphasizes the importance of alkalinization and the correction of dehydration in the treatment of hyperkalemia in neonatal calves with diarrhea

Effects of Alkalinization and Rehydration on Plasma Potassium Concentrations in Neonatal Calves with Diarrhea

BackgroundIncreased plasma potassium concentrations (K+) in neonatal calves with diarrhea are associated with acidemia and severe clinical dehydration and are therefore usually corrected by intravenous administration of fluids containing sodium bicarbonate. ObjectivesTo identify clinical and laboratory variables that are associated with changes of plasma K+ during the course of treatment and to document the plasma potassium-lowering effect of hypertonic (8.4%) sodium bicarbonate solutions. AnimalsSeventy-one neonatal diarrheic calves. MethodsProspective cohort study. Calves were treated according to a clinical protocol using an oral electrolyte solution and commercially available packages of 8.4% sodium bicarbonate (250-750mmol),0.9% saline (5-10L),and 40% dextrose (0.5L) infusion solutions. ResultsInfusions with 8.4% sodium bicarbonate solutions in an amount of 250-750mmol had an immediate and sustained plasma potassium-lowering effect. One hour after the end of such infusions or the start of a sodium bicarbonate containing constant drip infusion, changes of plasma K+ were most closely correlated to changes of venous blood pH, plasma sodium concentrations and plasma volume (r=-0.73,-0.57,-0.53;P<.001). Changes of plasma K+ during the subsequent 23hours were associated with changes of venous blood pH, clinical hydration status (enophthalmos) and serum creatinine concentrations (r=-0.71, 0.63, 0.62;P<.001). Conclusions and Clinical ImportanceThis study emphasizes the importance of alkalinization and the correction of dehydration in the treatment of hyperkalemia in neonatal calves with diarrhea

Patient's thoughts and expectations about centres of expertise for PKU

Background: In the Netherlands (NL) the government assigned 2 hospitals as centres of expertise (CE) for Phenylketonuria (PKU), while in the United Kingdom (UK) and Germany no centres are assigned specifically as PKU CE's. Methods: To identify expectations of patients/caregivers with PKU of CEs, a web-based survey was distributed through the national Phenylketonuria societies of Germany, NL and UK. Results: In total, 105 responded (43 patients, 56 parents, 4 grandparents, 2 other) of whom 59 were from NL, 33 from UK and 13 from Germany. All participants (n = 105) agreed that patients and/or practitioners would benefit from CEs. The frequency patients would want to visit a CE, when not treated in a CE (n = 83) varied: every hospital visit (24%, n = 20), annual or bi-annual (45%, n = 37), at defined patient ages (6%, n = 5), one visit only (22%, n = 18), or never (4%, n = 3). Distance was reported as a major barrier (42%, n = 35). 78% (n = 65) expected CE physicians and dieticians to have a higher level of knowledge than in non-CE centres. For participants already treated in a CE (n = 68), 66% requested a more extensive annual or bi-annual review. In general, psychology review and neuropsychologist assessment were identified as necessary by approximately half of the 105 participants. In addition, 66% (n = 68) expected a strong collaboration with patient associations. Conclusion: In this small study, most participants expected that assigning CEs will change the structure of and delivery of Phenylketonuria care

Undiagnosed Phenylketonuria Can Exist Everywhere: Results From an International Survey

Many countries do not have a newborn screening (NBS) program, and immigrants from such countries are at risk for late diagnosis of phenylketonuria (PKU). In this international survey, 52 of 259 patients (20%) with late diagnosed PKU were immigrants, and 145 of the 259 (55%) were born before NBS or in a location without NBS

Untreated PKU patients without intellectual disability: What do they teach us?

Phenylketonuria (PKU) management is aimed at preventing neurocognitive and psychosocial dysfunction by keeping plasma phenylalanine concentrations within the recommended target range. It can be questioned, however, whether universal plasma phenylalanine target levels would result in optimal neurocognitive outcomes for all patients, as similar plasma phenylalanine concentrations do not seem to have the same consequences to the brain for each PKU individual. To better understand the inter-individual differences in brain vulnerability to high plasma phenylalanine concentrations, we aimed to identify untreated and/or late-diagnosed PKU patients with near-normal outcome, despite high plasma phenylalanine concentrations, who are still alive. In total, we identified 16 such cases. While intellectual functioning in these patients was relatively unaffected, they often did present other neurological, psychological, and behavioral problems. Thereby, these “unusual” PKU patients show that the classical symptomatology of untreated or late-treated PKU may have to be rewritten. Moreover, these cases show that a lack of intellectual dysfunction despite high plasma phenylalanine concentrations does not necessarily imply that these high phenylalanine concentrations have not been toxic to the brain. Also, these cases may suggest that different mechanisms are involved in PKU pathophysiology, of which the relative importance seems to differ between patients and possibly also with increasing age. Further research should aim to better distinguish PKU patients with respect to their cerebral effects to high plasma phenylalanine concentrations