A 6-month-old infant is being transported via air for severe dehydration secondary to gastroenteritis. Upon assessment, the infant is lethargic, has sunken eyes, and poor skin turgor. What is the most appropriate initial management for this patient?
Monitoring vital signs closely without fluid resuscitation
Initiating fluid therapy with a glucose-containing solution
Fluid resuscitation with isotonic fluids
Administration of antibiotic therapy