Fluids, Electrolytes, Acid-Base Disorders, and Nutrition Support

A 70-year-old man admitted to the intensive care

unit (ICU) for sepsis was recently given a diagnosis

of syndrome of inappropriate antidiuretic hormone

(SIADH) secretion. His serum sodium fell from 130

mEq/L to 115 mEq/L during the past 3 days, and his

course was subsequently complicated by a seizure.

Which would be the most appropriate treatment

option?

Other than the absorption/infusion rate, which best

explains why enteral potassium administration is

safer than parenteral potassium administration?

of

potassium

is

signifi-

cantly lower with enteral versus parenteral

administration.

teric potassium concentration increases urinary

potassium excretion.

rhea and reduce potassium absorption.

throughout the gastrointestinal (GI) tract.

A 40-year-old man (weight 60 kg) is admitted to the

trauma ICU after a motor vehicle collision. He is

noted to have a serum magnesium concentration of

1.2 mg/dL, and his family states that he has a his-

tory of alcohol use disorder (12–18 beers/day). He

is given magnesium sulfate 6 g intravenously for

6 hours by the primary service. His repeat serum

magnesium concentration on the following day is

1.8 mg/dL. Which would be the most appropriate

treatment for this patient?

magnesium concentration is normal.

2 mg/dL or greater, no additional magnesium

therapy is indicated.

concurrently with the magnesium therapy.

daily for the next 4–5 days.

A 45-year-old man (weight 78 kg) with a history

significant for hypertension and pancreatitis is

admitted to the ICU after operative management

of necrotizing pancreatitis. He is given PN consist-

ing of 650 g of dextrose, 120 g of amino acids, and

55 g of injectable lipid emulsion (ILE) daily. Blood

glucose (BG) measurements over the past 24 hours

have been 180-325 mg/dL. Which change to this

patient’s nutrition regimen is most appropriate at

this time?

insulin aspart every 4 hours.

PN to 200 g and advance to dextrose 650 g once

blood glucose is less than 180 mg/dL.

remaining kilocalories by increasing protein to

160 g.

mic control over the next 24 hours.

A 48-year-old man is admitted to the trauma ICU

after a motorcycle collision. His injuries include

a subarachnoid hemorrhage, right pneumothorax,

multiple rib fractures, grade 5 liver laceration, right

sacral fracture, and transverse process fractures. His

course is complicated by respiratory failure, acute

kidney injury (AKI), and hyperglycemia. His labs

today reveal serum sodium 141 mEq/L, chloride

102 mEq/L, carbon dioxide 20 mEq/L, and lactate

2.6 mmol/L. His arterial blood gas values are as

follows: pH 7.46, Pco2 31 mmHg, and HCO3 22

mEq/L, Which of the following assessments of his

acid-base status is correct?

metabolic acidosis.

respiratory alkalosis.