TABLE 22.3 OTHER CONSIDERATIONS FOR VOMITING ALONE Diabetic ketoacidosis Increased intracranial pressure Otitis media Heart failure Obstruction (e.g., pyloric stenosis) Urinary tract infection Ingestion Age of the child, nutritional status, and type of dehydration may also affect clinical assessment, which is critical to effective management of the acutely dehydrated child In general, older children show signs of dehydration sooner than babies because of their lower levels of extracellular water Babies with excess subcutaneous fat may look less dehydrated than they really are, whereas severely malnourished babies may appear to be more dehydrated secondary to wasted supporting tissues Signs of dehydration may be less evident or appear later in hypernatremic dehydration Excessive irritability with increased muscle tone, and doughy or smooth and velvety skin, often are noted with this type of dehydration Conversely, signs of dehydration may be more pronounced or appear sooner in hyponatremic dehydration Keeping these observations in mind, particular attention should be paid to the overall appearance, mental status, eyes, and skin on physical examination Patients with obvious burns or diseases that disrupt the integument in the same way (e.g., scalded skin syndrome) are presumed to have become dehydrated through transudation of fluid through the skin Additional considerations are listed in Table 22.1 The mildly dehydrated child usually appears well or may be tired, have decreased tearing, and a slightly dry mouth Dry mucous membranes are an early sign of dehydration, but this finding is affected by rapid breathing and ingestion of fluids Conversely, the severely dehydrated baby classically appears quite ill with lethargy or irritability, a dry mouth, sunken fontanel, and absent tears Moderate states of dehydration, however, require careful evaluation One of the more objective measures of dehydration is assessment of skin perfusion by measuring capillary refill time Although the child’s body temperature does not predictably affect capillary refill time, it may be falsely prolonged when measured on the foot or in a cool room