Podcast 833: NS vs LR

<p><strong>Contributor: Travis Barlock, MD</strong></p> <p><strong>Educational Pearls:</strong></p> <ul> <li style="font-weight: 400;" aria-level="1"><span style= "font-weight: 400;">Normal Saline (NS) contains 154 mEq of both Sodium (Na) and Chloride (Cl),  and has a pH of 5.5</span></li> <ul> <li style="font-weight: 400;" aria-level="2"><span style= "font-weight: 400;">Normal Na and Cl in adult humans are about 140 mEq/L and 103 mEq/L. respectively </span></li> </ul> <li style="font-weight: 400;" aria-level="1"><span style= "font-weight: 400;"> Excess negative charge resulting from hyperchloremia is managed via bicarbonate excretion leading to loss of base</span></li> <ul> <li style="font-weight: 400;" aria-level="2"><span style= "font-weight: 400;">Overall, administration of NS drives metabolic acidosis</span></li> </ul> <li style="font-weight: 400;" aria-level="1"><span style= "font-weight: 400;">Lactated Ringers (LR) contains 130 mEq of Na and 109 mEq Cl, and has a pH of 6.5  </span></li> <li style="font-weight: 400;" aria-level="1"><span style= "font-weight: 400;">LR components are closer to physiologic levels thus may generally be a more efficacious fluid choice  </span></li> <li style="font-weight: 400;" aria-level="1"><span style= "font-weight: 400;">NS is still frequently given in scenarios where there is concern for increased intracranial pressure or existing hypochloremic alkalosis from emesis. </span></li> </ul> <p><strong>References</strong><span style= "font-weight: 400;"><br /></span><span style="font-weight: 400;">Li H, Sun SR, Yap JQ, Chen JH, Qian Q. 0.9% saline is neither normal nor physiological.</span> <em><span style="font-weight: 400;">J Zhejiang Univ Sci B</span></em><span style="font-weight: 400;">. 2016;17(3):181-187. doi:10.1631/jzus.B1500201</span></p> <p><span style="font-weight: 400;">​​Lehr AR, Rached-d'Astous S, Barrowman N, et al. Balanced Versus Unbalanced Fluid in Critically Ill Children: Systematic Review and Meta-Analysis.</span> <em><span style="font-weight: 400;">Pediatr Cr