Oral fluid therapy in neonatal ruminants and swine

Impacto de diferentes soluções eletrolíticas orais sobre a glicemia e os equilíbrios hídrico, eletrolítico e ácido-base de bezerros neonatos sadios

RESUMO Este trabalho objetivou estudar os efeitos de quatro soluções eletrolíticas orais (SEO) comerciais, de uma SEO não comercial (SEO UEL) e da solução de ringer com lactato (SRL), sobre a glicemia e os equilíbrios hídrico, eletrolítico e ácido-base de bezerros neonatos sadios. Utilizaram-se seis bezerros, os quais receberam todas as seis SEO, uma por vez, e cada tratamento foi realizado no período de um dia. Amostras de sangue venoso foram coletadas, em diferentes momentos do dia de tratamento, para a determinação da proteína plasmática total, glicemia e hemogasometria. Valores de SID3 e variação do volume plasmático foram calculados. A análise de variância de medidas repetidas foi empregada para comparação entre os momentos e as soluções. As SEO não provocaram alterações de magnitude alta ou prolongadas nos equilíbrios hídrico, eletrolítico e ácido-base dos bezerros. Pode-se concluir que todas as SEO, à exceção da SEO A, originaram expansão da volemia. As SEO B e C originaram efeito alcalinizante, enquanto a D afetou a glicemia, e a SRL aumentou a cloremia. A SEO UEL não produziu nenhum efeito marcante além da expansão do volume plasmático.

Importance of the effective strong ion difference of an intravenous solution in the treatment of diarrheic calves with naturally acquired acidemia and strong ion (metabolic) acidosis

BACKGROUND

The effect of sodium bicarbonate on acid-base balance in metabolic acidosis is interpreted differently by Henderson-Hasselbalch and strong ion acid-base approaches. Application of the traditional bicarbonate-centric approach indicates that bicarbonate administration corrects the metabolic acidosis by buffering hydrogen ions, whereas strong ion difference theory indicates that the co-administration of the strong cation sodium with a volatile buffer (bicarbonate) corrects the strong ion acidosis by increasing the strong ion difference (SID) in plasma.

OBJECTIVE

To investigate the relative importance of the effective SID of IV solutions in correcting acidemia in calves with diarrhea.

ANIMALS

Twenty-two Holstein-Friesian calves (4-21 days old) with naturally acquired diarrhea and strong ion (metabolic) acidosis.

METHODS

Calves were randomly assigned to IV treatment with a solution of sodium bicarbonate (1.4%) or sodium gluconate (3.26%). Fluids were administered over 4 hours and the effect on acid-base balance was determined.

RESULTS

Calves suffered from acidemia owing to moderate to strong ion acidosis arising from hyponatremia and hyper-D-lactatemia. Sodium bicarbonate infusion was effective in correcting the strong ion acidosis. In contrast, sodium gluconate infusion did not change blood pH, presumably because the strong anion gluconate was minimally metabolized.

CONCLUSIONS

A solution containing a high effective SID (sodium bicarbonate) is much more effective in alkalinizing diarrheic calves with strong ion acidosis than a solution with a low effective SID (sodium gluconate). Sodium gluconate is ineffective in correcting acidemia, which can be explained using traditional acid-base theory but requires a new parameter, effective SID, to be understood using the strong ion approach.

Treatment of calf diarrhea: oral fluid therapy

Diarrhea remains the leading cause of mortality in beef and dairy calves. Calves that have diarrhea frequently develop dehydration, strong ion acidosis, and electrolyte abnormalities, and are in a state of negative energy balance. Oral electrolyte therapy is a simple and economical method of addressing all of these potential complications. This article gives an overview of oral electrolyte therapy of calves, including indications, guidelines for administration, and how to choose an electrolyte product.

Evaluation of isotonic sodium bicarbonate solution for alkalizing effects in conscious calves

After intravenous (i.v.) infusion of various volumes of 1.35%-isotonic sodium bicarbonate solution (ISB), acid-base equilibrium, blood pressure, plasma volume and biochemical parameters in healthy Holstein calves were studied. Four calves each were randomly assigned to the low-dose (LD; i.v. infusion of 5 ml/kg ISB), middle-dose (MD; i.v. infusion of 10 ml/kg ISB) and the high-dose groups (HD; i.v. infusion of 15 ml/kg ISB). Administration volumes of ISB in the LD, MD and HD groups were decided based on the first half volumes of 5, 10 and 15 mEq of base requirement by the acceptable equation. Systemic, pulmonary artery and central venous pressures, cardiac output and plasma osmotic pressure were not changed by ISB infusion and remained constant throughout the experiment for all groups. There was good correlation (r(2) = 0.950) between relative changes in base excess and infused volume of bicarbonate (y=2.491x). The coefficient of distribution for bicarbonate ions was calculated to be 0.401 (=1/2.491). Therefore, it is suggested that a value of 0.4 would be most appropriate when calculating the base requirements in calves. Therefore, the first half volumes of ISB correcting base deficits of 5, 10 and 15 mEq in calves were estimated to be 6, 12 and 18 ml/kg, respectively. On the basis of the findings in this study, ISB may be used to correct metabolic acidosis without altering the plasma osmotic pressure, hemodynamic status and respiratory function in the calves.

Oral electrolyte therapy

Diarrhea is a common condition in neonatal calves and can be caused by a wide variety of infections and noxious agents. Oral electrolyte therapy is a simple and economical method of treating diarrheic calves. Oral electrolyte solutions can correct dehydration and acidosis, and they may also have a role in preventing or alleviating mucosal damage. Indications, the principles of administration, and choosing an electrolyte product are discussed with examples.

Intravenous fluid therapy of calves

Dehydration in neonatal calves with diarrhea is a common cause of death. Severely dehydrated calves that are unable to suckle need intravenous fluids for effective resuscitation. This article gives an overview of the principles of intravenous fluid therapy for dehydrated calves including the types of fluids commonly used and methods of fluid administration. Practical on-farm options for simple clinical assessment and treatment of dehydration and acidosis in calves are also discussed in this article.

Fallibility of faecal consistency as a criterion of success in the evaluation of oral fluid therapy for calf diarrhoea

It is often said that the success of oral rehydration in humans depends on the adequacy of the improvement in the composition and volume of extracellular fluid, not reduction of faecal output. Indeed, the latter may increase initially. Such increases do not prevent the treatment from being effective but they may, falsely, undermine its acceptability to patients or those caring for them. This paper provides data to show that standard oral rehydration solutions used to treat experimentally induced calf diarrhoea procure identical improvements in plasma volume during the first 48 h, whether faeces improve or not, and those calves whose faecal consistency improved actually showed greater deterioration of extracellular fluid volume. While it is important for this to be appreciated by clinicians and explained to owners, it is absolutely imperative that those responsible for the approval of new therapeutic products for registration understand and accept that faecal consistency offers no reliable insight into the effectiveness of oral rehydration therapy for calf diarrhoea. It was, however, interesting that there was some relationship with correction of acidosis--perhaps because some of the contributing factors arise from colonic dysfunction.

Whole milk and oral rehydration solution for calves with diarrhea of spontaneous origin

Forty-two calves (mean 10 d of age) that spontaneously contracted diarrhea were used to test the therapeutic value of an oral rehydration solution with or without whole milk. Therapy began on the first feeding after a fecal score was > 2 (five-point scale). Amounts (percentages of BW daily) of milk and oral rehydration solution on d 1 and 2, 3 and 4, 5 and 6, and 7 for treatments 1, 2, and 3 were 1) 0 and 10, 5 and 5, 7.5 and 2.5, 10 and 0% (in two feedings); 2) 2.5 and 10, 5 and 7.5, 7.5 and 5, 10 and 0% (in two feedings); 3) 10 and 10, 10 and 5, 10 and 2.5, 10 and 0% (in three feedings). Oral rehydration solution was fed 15 min after milk. Fecal score, rectal temperature, packed cell volume of whole blood, concentrations of glucose and electrolytes in serum, and strong ion difference of serum were unaffected by treatments. Calves given treatment 3 gained BW throughout the experiment, whereas those given treatments 1 and 2 lost BW during the first 3 d of therapy. Fecal cultures indicated that 70% of calves were infected with Cryptosporidium on d 1 of therapy. No mortality occurred. Whole milk and oral rehydration solution fed to calves did not adversely affect calves or prolong or worsen diarrhea but promoted gain of BW.