Prepartum anionic diet induces hyperchloremic acidosis in high-producing dairy cows without preventing subclinical hypocalcemia / Dieta aniônica pré-parto provoca acidose hiperclorêmica em vacas leiteiras de alta produção mas não evita a hipocalcemia subclínica

In this study we evaluated the effects of the prepartum anionic diet on the electrolyte balance and calcemia of high producing dairy cows in the first days of lactation, and investigated the impact on the frequency of subclinical hypocalcemia (SCH). Sixty healthy Holstein cows, producing 30 kg of milk/day, handled in intensive system (compost barn), were distributed in groups (n=15) according to lactation order: first, second, third, and fourth to sixth. In the last three weeks before calving they received a diet with negative DCAD (-6mEq/100g DM) and high chloride content. After calving, they received a diet with positive DCAD (18mEq/100g DM). Urine pH was measured before calving. Serum Na+, Cl-, K+, and total Ca concentrations, and the strong ion difference (SID3) were determined in samples taken soon after calving (0h), 24, 48, 72 and 96h after. The frequencies of SCH were determined considering the critical value of 2.125mmol/L (8.5mg/dL). Two-way repeated measures ANOVA and chi-square test were used for comparisons. The cows eliminated acidic urine before calving. Na+, K+, Cl-, and SID3 values did not differ between groups. Na+ and K+ did not vary between days; Cl- was elevated at calving and decreased until 72h; and SID3 was reduced at calving and increased up to 48h. The Ca levels were reduced until 24h and increased up to 72h. Cows of third and fourth to sixth lactations presented lower values up to 24h. SCH was observed in almost half of the cows (43.3% to 55%) until 48h. The maintenance of hypocalcemia for three or more consecutive days occurred in 53.3% of third and fourth to sixth lactations cows. Ingestion of a high chloride prepartum anionic diet led to hyperchloremic acidosis and this imbalance was reversed on the second postpartum day. The induced effects on electrolyte and acid-base balances were not able to prevent the occurrence of SCH in the first days of lactation.(AU)

Os objetivos do estudo foram avaliar os efeitos que a dieta aniônica pré-parto provoca sobre o equilíbrio eletrolítico e sobre a calcemia de vacas leiteiras de alta produção nos primeiros dias de lactação, e verificar o impacto sobre a frequência da hipocalcemia subclínica (HSC). Sessenta fêmeas hígidas HPB, com produção de 30 kg de leite/dia, manejadas em sistema intensivo (compost barn), foram distribuídas por grupos (n=15) de acordo com a ordem de lactação: primeira, segunda, terceira e quarta a sexta. Nas três semanas pré-parto receberam dieta com DCAD negativa (-6mEq/100g MS) e teor de cloreto elevado. Após o parto receberam dieta com DCAD positiva (18mEq/100g MS). O pH da urina foi mensurado antes do parto. As concentrações séricas de Na+, Cl-, K+ e Ca total e a diferença de íons fortes (SID3) foram determinadas em amostras colhidas ao parto (0h), 24, 48, 72 e 96h após. As frequências de HSC foram determinadas considerando-se o valor crítico de 2,125mmol/L (8,5mg/dL). ANOVA de medidas repetidas e teste de qui-quadrado foram empregados para as comparações. As vacas eliminavam urina ácida antes do parto. Os valores de Na+, K+, Cl- e SID3 não diferiram entre os grupos. Na+ e K+ não variaram entre os dias; Cl- era elevado ao parto e diminuiu até 72h; e SID3 era reduzida ao parto e aumentou até 48h. A calcemia era reduzida até 24h e se elevou até 72h. Vacas de terceira e de quarta a sexta lactações apresentaram valores mais baixos até 24h. A HSC foi observada em quase metade das vacas (43,3% a 55%) até 48h. A manutenção de hipocalcemia por três ou mais dias seguidos ocorreu em 53,3% das vacas de terceira e de quarta a sexta lactações. A ingestão de dieta aniônica pré-parto com alto teor de cloreto provocou acidose hiperclorêmica e este desequilíbrio se reverteu no segundo dia pós-parto. Os efeitos induzidos sobre os equilíbrios eletrolítico e ácido base não foram capazes de prevenir a ocorrência de HSC nos primeiros dias da lactação.(AU)

Treatment of acute rumen lactic acidosis with intravenous hypertonic sodium chloride or bicarbonate solutions followed by intraruminal water.

The effectiveness of 7% hypertonic saline solution (HSS) and 6% hypertonic bicarbonate solution (HBS) followed by intraruminal water administration for the treatment of acute rumen lactic acidosis (ARLA) has not been evaluated yet. The hypothesis of the study is that treatment with HBS causes a faster correction of imbalances and clinical recovery than treatment with HSS. ARLA was induced in six healthy mature female sheep with sucrose twice. The sheep received both treatment regimens in a cross over design. After 18 h of induction, rumen lavage was performed and IV infusion of 7% HSS (4 mL/kg BW) or 6% HBS (6.7 mL/kg BW) was done over 5 min, followed by intraruminal administration of water (8% BW). The solutions provided 4.8 mmol/kg BW of sodium. Physical and laboratory tests were performed for 168 h. Both treatments increased plasma volume. After HSS treatment, pH and HCO3- returned to baseline values at 144 h and BE at 168 h. With HBS treatment, pH returned to baseline at 24 h, and HCO3- and BE at 48 h. In both treatments, the ruminal motility and the maximum hay intake were restored at 96 and 120 h, respectively. In conclusion, administration of HSS or HBS followed by intraruminal water corrects dehydration and mild-to-moderate metabolic acidosis in sheep with ARLA. Treatment with HBS promoted a faster correction of metabolic acidosis and could be indicated for the most severe cases.

Myocardial infarction with nonobstructive coronary arteries: a single-center retrospective study.

BACKGROUND: Myocardial infarction (MI) with nonobstructive coronary arteries (MINOCA) is a heterogeneous entity often overlooked in contemporary medicine. We aim to determine MINOCA differential characteristics, the main etiologies, and prognostic outcomes. PATIENTS AND METHODS: We carried out a retrospective longitudinal analysis including 1047 patients with MI, from 1 January 2011 to 1 January 2016, subjected to coronary angiography and classified according to the presence [MI and obstructive coronary artery disease (MICAD)] or absence (MINOCA) of any coronary stenosis of at least 50%. Studied data included clinical, demographic, laboratorial, and angiographic features. The median follow-up duration was 35 (interquartile range: 25) months. Mortality was the primary endpoint. To identify MINOCA underlying etiologies, only the final diagnosis obtained according to the European Society of Cardiology proposed algorithm was accepted. To determine MINOCA predictors, multivariate analysis with logistic regression was carried out. RESULTS: The mean age of the patients was 66.3±13.4 years; 319 (30.5%) patients were women. The MINOCA group included 114 (10.8%) patients. The underlying final diagnosis in the MINOCA group was obtained in 78 (68.4%) patients. The total mortality rate was 8.8% (n=10) in the MINOCA group versus 17.7% (n=165) in the MICAD group, P=0.018. After multivariate analysis, age [odds ratio (OR)=1.05, 95% confidence interval (CI): 1.03-1.07, P<0.001], female sex (OR=3.91, 95% CI: 2.53-6.06, P<0.001), no previous tobacco use (OR=3.41, 95% CI: 1.68-3.90, P=0.001), atrial fibrillation (OR=3.62, 95% CI: 1.56-8.40, P=0.003), no previous AMI (OR=6.85, 95% CI: 1.65-28.5, P=0.008), and non-ST-segment elevation myocardial infarction diagnosis (OR=5.36, 95% CI: 2.62-10.96, P<0.001) remained independent predictors of MINOCA. CONCLUSION: MINOCA represents a challenging group of heterogeneous patients whose clinical characteristics contrast with classical cardiovascular risk factors. Despite lower mortality than MICAD, the commonly attributed low-risk classification for MINOCA may be erroneous.