Case #3 Answers:

Answer 1

• Is the patient symptomatic? Is the patient febrile? How much fluid has the patient received in total? Has the patient received her medicines (BP)? What is her urine output?

  ·         Why is the patient hypotensive? Shock differential 1. Hypovolemic 2. Septic 3. Cardiogenic 4. Blood loss 5. Adrenal insufficiency

Answer 2

• In theory, the response shouldn't be much different (assuming that the child's BP is low for his/her age).
• 20 cc/kg over 20 min (about a liter) is the ideal bolus (in form of NS) with reevaluation after each bolus
• If the BP and additional vital signs do not respond to 3 boluses, investigation into additional etiologies (hemorrhage, adrenal insufficiency) as well as planning for pharmacologic pressor support (transfer to the ICU).
• There is evidence that crystalloid is as efficacious as colloid (albumin). No evidence in RCTs that albumin particularly in hypovolemic patients. 

  The choice of fluid for resuscitation of patients with hypovolemic or septic shock is a source of intense debate.There are not enough prospective, controlled trials to support LR over NS. The clinical outcome–based evidence supporting LR over NS is  derived from post hoc retrospective analyses of large patient data sets. The available data do not support the use of colloids over crystalloids in acute illness. AKi secondary to chloride rich fluid has been seen in animals perhaps and but not supported in humans.  Here are some articles that may be used for reference for the students:

  ·         Myburgh et al Resuscitation Fluids. N Engl J Med 2013; 369:1243-1251

  ·         Kellum et al Assessing Toxicity of Intravenous Crystalloids in Critically Ill Patients JAMA. 2015;314(16):1695-1697

  ·         Raghunathan et al. Choice of fluid in acute illness: what should be given? An international consensus. Br J Anaesth (2014) 113 (5): 772-783

Answer 3

• Probably hypokalemic due to diuretics superimposed on losses from the GI tract (diarrhea)
• Most authors recommend IV and oral potassium replacement with levels less than 3.5 meQ/L.
• IV replacement can be done no faster than 10meQ/L / hour through a peripheral IV; no faster than 20meQ/L through a central line
• Potassium is often replaced with an anion (Cl-, HCO3-); if the particular anion is low, it can be replaced in combination with potassium.
• Tablet forms of potassium replacement are more easily tolerated than liquid preparations
• Be careful in replacing potassium in patients with kidney disease or acute kidney failure. Administer half the usual dose and then reassess. Avoid K+ containing fluids such as LR or Plasmalite.

Answer 4

• Magnesium: Hypomagnesemia can result in refractory hypokalemia. Literature suggests that magnesium deficiency exacerbates potassium wasting by increasing distal potassium secretion. Thus, magnesium levels should be checked and normalized. Additionally, many conditions that deplete potassium will also deplete magnesium (diuretics, diarrhea, malnutrition, refeeding syndrome
  •  
    • Huang et al, Mechanism of Hypokalemia in Magnesium Deficiency. JASN October 2007 vol. 18 no. 10 2649-2652