Sept week 2: Oral rehydration


Santosham M, et al.  Oral Rehydration Therapy and Dietary Therapy for Acute Childhood Diarrhea.  Peds in Review.  1987;8;273-278.

Case 1:
You are seeing a 9 month old boy in the ED who presents with vomiting and diarrhea.  Mom reports the illness began 4 days ago with vomiting up to 8 times a day.  Vomiting has mostly resolved but now the infant has developed watery diarrhea.

How do you determine the patient’s hydration status?                  
How do you proceed with this patient in the ED?                         
Once the child is rehydrated, how do you advise mom to reintroduce solid foods?  

Prep Questions:

2009, # 3
You are seeing a 1-month-old girl for follow-up after a hospitalization for acute gastroenteritis caused by rotavirus. Her diarrhea had decreased in the hospital while taking oral rehydration solution, but when her mother resumed her usual cow milk formula, the girl began to have an increased number of very watery stools. She appears well hydrated, and findings on her abdominal examination are normal.
Of the following, the MOST appropriate approach to managing this infant’s diarrhea is to
A.    Change to a lactose free formula for the next few days
B.    Dilute the cow milk formula with ORS for the next few days
C.    Give her only ORS until the diarrhea resolves
D.    Readmit her to the hospital for administration of IVF
E.    Repeat her stool studies to confirm the diagnosis of rotavirus
2009, # 137
You are evaluating a 2-week-old breastfed infant who is 15% below his birthweight and has been lethargic and fed poorly over the past 4 days. You administer a normal saline fluid bolus. Laboratory results include: 
•    Blood glucose of 126.0 mg/dl (7.0 mmol/L)
•    Serum sodium of 170.0 mEq/L (170.0 mmol/L)
•    Serum potassium of 5.0 mEq/L (5.0 mmol/L)
•    Blood urea nitrogen of 31.0 mg/dL (11.1 mmol/L)
•    Serum creatinine of 2.9 mg/dL (256.4 mcmol/L)
Of the following, the MOST appropriate initial fluid for correction is a solution containing 5% dextrose and
A.    0.20 NaCl (%), 40 KCl (mEq/L), Duration of Infusion(hr) 12 to 24 
B.    0.45 NaCl (%), 0 KCl (mEq/L), Duration of Infusion(hr) 48 to 72
C.    0.45 NaCl (%), 40 KCl (mEq/L), Duration of Infusion(hr) 12 to 24
D.    0.9 NaCl (%), 0 KCl (mEq/L), Duration of Infusion(hr)  12 to 24
E.    0.9 NaCl (%), 40 KCl (mEq/L), Duration of Infusion(hr) 48 to 72
2010, #129
A 5-month-old infant who has been fed cow milk protein-based formula presents to the emergency department following 2 days of watery diarrhea that she has passed up to 10 times per day. She weighed 3,100 g when born at term and has been gaining weight and growing normally. Her weight at the 4-month visit was 5.5 kg. On physical examination today, her weight is 5.8 kg, temperature is 37.7°C, and heart rate is 140 beats/min. She appears alert, her mucous membranes are dry, and skin recoil is less than 2 seconds. Capillary refill is slightly prolonged. The remainder of the physical examination findings are unremarkable.
Of the following, the MOST appropriate immediate treatment is
A.    intravenous hydration with an initial infusion of 120 mL 0.9% sodium chloride over 2 hours
B.    intravenous hydration with 5% dextrose and 0.33% sodium chloride at 40 mL/hr
C.    oral feedings with half-strength soy-based formula, mixed 1:1 with a glucose-electrolyte solution
D.    oral rehydration with a solution containing 20 mEq/L sodium chloride
E.    oral rehydration with a solution containing 75 mEq/L sodium chloride
2010, #113
A 3½-week-old male infant presents to your office with a history of 2 to 3 days of vomiting. He was born at term and his birthweight was 3,250 g. He is breastfed. He has been exhibiting nonbilious vomiting after each feeding, and according to his mother, the emesis now appears to “shoot out of his mouth.” After vomiting, he seems eager to resume feeding. Over the past 24 hours, his mother has noted fewer wet diapers and less stool than usual. The baby has experienced no diarrhea or upper respiratory tract symptoms. Physical examination demonstrates an alert, afebrile infant who weighs 3,550 g and is sucking vigorously on a pacifier. His skin turgor is normal. The remainder of the examination findings are unremarkable, except for slight abdominal distention. You refer the baby to the local emergency department and order measurement of serum electrolytes. Results include: 
•    Sodium, 132 mEq/L (132 mmol/L)
•    Potassium, 3.2 mEq/L (3.2 mmol/L)
•    Chloride, 95 mEq/L (95 mmol/L)
•    Bicarbonate, 30 mEq/L (30 mmol/L)

Of the following, the MOST appropriate initial treatment for this infant is to
A.    administer 70 mL 0.9% sodium chloride intravenously over 1 hour, followed by infusion with 5% dextrose and 0.225% sodium chloride at 15 mL/hr
B.    begin intravenous fluids with 5% dextrose and 0.3% sodium chloride at 15 mL/hr
C.    encourage continued nursing, pending results of further diagnostic tests
D.    initiate intravenous fluids containing 5% dextrose and 0.45% sodium chloride at 25 mL/hr
E.    institute oral rehydration therapy with a glucose-electrolyte solution