The main findings of this study are the demonstration that acetate Ringer’s solution is safe as a resuscitation medium, and further, that it might have some clinical advantages when compared to lactate Ringer’s solution as a control group.
Administration of intravenous solutions required to correct physiological functions that have been altered due to surgical stress and anesthetic agents and to maintain body homeostasis to provide oxygen to the tissues[8]. In this way, the fluid deficiency is replaced, sufficient tissue perfusion is provided and the unwanted effects of anesthetics are tried to be removed.
High lactate level have been associated with poor outcomes in the critically ill patients[9]. Lactate was initially introduced as an alkali. Its alkalinizing effect depends on its reutilization for glucose synthesis and its oxidative degradation to H2O and CO2, which converts into bicarbonate. Abnormalities of lactate metabolism are very common in patients undergoing prolonged surgery. The metabolism of lactate is dependent on the kidney and liver, and as such, when the functions of these organs are compromised, there will be lactate accumulation [10]. Although we observed that lactate level was significantly higher in Group LR than in Group AR at the end of surgery, it was within the normal range. We hypothesised that liver function was limited to metabolise the lactate with biliary atresia patients and the lactate was accumulated, but the liver has a functional reserve and can metabolise lactate. Acetate is metabolized more efficiently in peripheral tissues. Its use in intravenous solutions is becoming popular, because it readily convertible to bicarbonate than lactate. The main organ that metabolizes lactate is liver, whereas acetate can be metabolized widely throughout the body and is not mainly dependent on the liver. In addition, acetate can be metabolized more quickly than lactate. This study showed no difference between the two groups in bicarbonate. In contrast, Kumar et al used acetated crystalloid as an intraoperative fluid and the levels of bicarbonate and base excess showed an improved profile[11]. Increase in lactate level is commonly observed if the volume of liver is inadequate following major hepatectomy[12]. Sunil et al found that the level of lactate in the lactated Ringer’s group was significantly higher than in the acetate solution group at the end of the operation[13]. In line with our result , acetated Ringer’s solution was found to be safer as compared to normal saline in protecting young children undergoing major surgery against the risk of increasing plasma chlorides and the subsequent metabolic acidosis [14].
This study showed that although serum chloride and serum sodium were significant higher at the end of surgery, the levels were within the normal range in both groups. The contribution of hyperchloremia toward persistent acidosis, however, did not seem to play a major role in our study population. Khan et al found that lactate Ringer’s solution to prevent hyperchloremic metabolic acidosis [15]. We demonstrated that AR and LR may play a less role in electrolyte disorders including hyperchloremic and hypernatremia with fluid resuscitation. Concerns about intravenous hypotonic fluids have focused on potential neurological sequelae associated with severe hospital-induced hyponatremia[16]. Hyponatremia is the most common electrolyte disorder in children, affecting approximately 25 % of hospitalized children and 30 % of children in the postoperative period, most of which occurred after uncomplicated surgeries[17]. Hyponatremic encephalopathy is the most crucial risk of acute hyponatremia and may result in permanent neurological damage or death. At least half of the cases documented with the diagnosis of hyponatremia in children occurred in the postoperative period, most of which occurred after uncomplicated surgeries. Stimulation of the antidiuretic hormone ( ADH ) may be due to hemodynamic causes such as hypovolemia and hypotension, other factors that cause hemodynamic-independent non-osmotic ADH release include postoperative status, positive pressure ventilation, pain, nausea, vomiting and the use of narcotic medication[18]. As a result of decreased diuresis effect of kidney due to ADH over stimulation, fluid retention and related dilutional hyponatremia increase the risk of hyponatremic encephalopathy in pediatric patients in perioperative period[19].
The hyponatremia was not found in both groups. Hence, we can draw the conclusion that administration of acetate Ringer's solution or lactate Ringer's solution may play a less role in leading hyponatremia in infants with biliary atresia. Intraoperative hypothermia is associated with numerous complications such as decreased drug metabolism, impairment of coagulation, and shivering[20]. In our study, we observed that the temperature was a signifcantly higher at postoperative 12 h in two groups. The temperature may be related to postoperative fever[21]. The inflammatory mechanisms accountable for postoperative fever have been the subject of a number of studies. Tissue damages alone results in the disruption of phospholipids from the cell membrane, leading to a cascade of prostaglandins and cytokines which ultimately lead to a body temperature elevation. There was no significant differences between the groups at other time points. We used forced-air prewarming before anesthesia induction to prevent the development of hypothermia. Hypothermia was not observed in infant patients.
The incidence of hypoglycemia during induction of anesthesia is reported to be between 0 % and 2.5 %. In most of the children identified with hypoglycemia, an average of 10 hours of
fasting times are reported. Hypoglycemia was not observed in
children who had drunk clear fluid up to 2 hours before surgery. [22]. Our study found that no hypoglycemia was recorded following fluid resuscitation in both groups. All infants patients received clear fluids containing 3 ml / kg glucose over the last 2 hour before surgery, according to their weight calculated in our study [23].
Limitations of the study include small sample size, lack of comparison of base excess. The data should have been collected up to postoperation 24 h. Postoperation coagulation function and hepatic function have not been assessed and analyzed. Hemodynamics have not been analyzed during operation. Only a single surgery was included in the study. Further research involving larger number of patients undergoing different surgeries is needed to know the acid base physiology in infant or neonatel patients.
In summary, resuscitation with AR and LR is associated with similar clinical improvement in infant with biliary atresia. Use of acetate Ringer's solution reduced levels of lactate in comparison with LR. Hence, AR is to be considered as the fluid of choice owing to the clinical improvement with the Kasai hepatoportoenterostomy.