PURPOSE: The key difference in evaluating the acid base status with simplified Fencl-Stewart’s equation, from others is that it identifies as well as quantifies individual components of complex acid-base abnormalities and thus provides insight into their pathogenesis. In this study Fencl-Stewart approach was applied to compare the acid base difference following resuscitation with two different fluids, normal saline (NS) or ringers lactate (RL).
METHODS: After obtaining approval from the departmental ethical committee and consent from the patients relative, 60 adult patients of either sex presenting with severe sepsis or septic shock were randomly assigned into two groups, (NS and RL), of 30 patients each. Patients were resuscitated with 20 ml/kg of fluids over a period of 30 minutes. Patients who reached the defined end point (CVP > 12 cm H2O, MAP > 65) mmHg before the administration of fluid were excluded from the study and a fresh case was taken. Patients in whom the CVP and the MAP did not reach the defined end point were continued with the resuscitation. The changes in the acid base status after administration of fluids were evaluated using the Fencl-Stewart approach: 1) Sodium-chloride effect on BE (meq/litre) = [Na+] - [Cl-] - 38, 2) Albumin effect on BE (meq/litre) = 0.25 × [42 - albumin (g/litre)] 3) Unmeasured ion on effect BE (meq/litre) = standard base excess - sodium chloride effect - albumin effect. Paired 't' test for intragroup and unpaired 't' test for inter group analysis
RESULTS: Administration of NS decreased pH (7.44 ± 0.11 to 7.19 ± 0.13, p < 0.05) whereas Sodium-chloride effect, albumin effect and unmeasured ion effect on BE increased (p < 0.05). In RL group only the albumin effect significantly increased, the rest did not achieve significance.
CONCLUSIONS: Fencl-Stewart approach identifies acid base abnormalities. NS causes hyperchloremic acidosis significantly more than RL. The acidosis is offset by the alkalosis caused by albumin and unmeasured anion effect. While the changes in acid base are least with RL.
CLINICAL IMPLICATIONS: Hence Ringers Lactate is a better option for patients who require rapid and large quantity of fluids.
DISCLOSURE: The following authors have nothing to disclose: Shiwani Agarwal, Syed Ahmed, Parul Maheshwari, Abu Nadeem, Mohd. Islam, Asif Siddiqui
No Product/Research Disclosure Information