**3.1 Clinical assessment of dehydration**

Current validated dehydration scales may help in assessing the versatile presentations of dehydration more objectively. Most of them illustrate clinical signs that can be assessed easily and rapidly, which can facilitate stratification of patients into dehydration categories. There are three clinical scales designed to estimate dehydration severity in children below 5 years of age: the World Health Organization (WHO) scale (**Table 1**), the Gorelick scale (**Table 2**), and the Clinical Dehydration Scale (CDS) (**Table 3**) [8–10].

Using common tools to evaluate and assess dehydration would be more helpful in day-to-day practice. Consistent evidence supports the CDS which is more useful and easy to use in assessing dehydration. This scale in combination with other criteria should be used to guide the proper medical interventions in individual


#### **Table 1.**

*Perspective of Recent Advances in Acute Diarrhea*

(<3 days), 80% of the deficit is typically from the ECF. After more than 3 days of illness, the deficit from the ECF decreases to 60%. Fluid losses for longer than 7 days

*The percentage distribution of body fluids in the various compartments in a 1-year-old infant [2].*

Accurate and quick assessment of the degree of dehydration is important for proper treatment and disposition of infants and children with AGE [6]. The percentage of weight loss is the best measure to assess the degree of dehydration, as shown in Eq. (1). However, this method is impractical because in most patients the

are equally lost from ECF (50%) and ICF (50%) [5].

**3. Assessment of dehydration**

*Body water compartments in relation to age [2–4].*

pre-illness weight is not known [7].

**38**

**Figure 1.**

**Figure 2.**

*WHO scale for dehydration in children aged 1 month–5 years old.*


#### **Table 2.**

*Gorelick (4-item) scale for dehydration in children aged 1 month–5 years. Scoring: ≥2 clinical signs indicates ≥ 5% loss of body weight from baseline (moderate dehydration), and ≥3 clinical signs indicates ≥ 10% loss of body weight from baseline (severe dehydration). The presence of two or more of these signs had a sensitivity of 79% and a specificity of 87% in predicting 5% dehydration.*


#### **Table 3.**

*Clinical dehydration scale (CDS) for children aged 1 month–3 years. Scoring: ≥2 clinical signs indicates ≥ 5% loss of body weight from baseline (moderate dehydration), and ≥3 clinical signs indicates ≥ 10% loss of body weight from baseline (severe dehydration). The presence of two or more of these signs had a sensitivity of 79% and a specificity of 87% in predicting 5% dehydration.*

cases [11]. Clinical dehydration scales are imprecise and of limited diagnostic value in children with gastroenteritis [12]. As a screening test of dehydration, historical points are moderately sensitive. Classification of dehydration into NO, SOME, and SEVERE are recommended by WHO and other groups [1, 8].

Prolonged capillary refill time, abnormal skin turgor, and abnormal respiratory pattern still remain the best three individual examination signs for assessment of dehydration. Increased capillary refill time was the strongest individual sign as an isolated finding to predict dehydration, and the poor predictor of dehydration was reduced urine output. Combinations of signs perform much better than individual signs. History taking and laboratory tests show limited utility [13].

#### **3.2 Laboratory assessment of dehydration**

Blood biochemistry is generally not accurate and not routinely required for assessment of dehydration. Commonly done laboratory tests such as blood urea nitrogen (BUN) and bicarbonate concentrations are generally helpful only when the results are markedly abnormal. A normal serum bicarbonate concentration of more than 15 or 17 mEq/L appears to be valuable in reducing the likelihood of dehydration. These laboratory tests done for assessing dehydration should not be considered definitive, which could be reserved for children requiring IV fluids and suffering from severe dehydration, altered conscious state or convulsions, suspected hypernatremia, suspicion of hemolytic uremic syndrome and children with pre-existing medical conditions that predispose to electrolyte abnormalities [14, 15]. Historical points and laboratory tests only have limited utility for assessing dehydration [10]. Laboratory investigations should be performed if the results will influence the management and outcome of a specific patient.

### **4. Management of dehydration**

Oral rehydration should be the first line of treatment for pediatric gastroenteritis with intravenous (IV) fluid therapy being used if the oral route fails [16, 17].

#### **4.1 Oral rehydration therapy (ORT)**

Oral rehydration is the preferred method for replacing fluid and electrolyte deficits resulting from dehydration secondary to acute gastroenteritis. ORT is a safe, easy-to-use, efficacious, and cost-effective alternative to intravenous rehydration for uncomplicated gastroenteritis in children [18].

The use of ORT is based on the principle of glucose-facilitated sodium transport across the intestinal mucosa. The ORT facilitates the absorption of water and sodium for the compensation of fluid losses. Additionally, the absorption can be adequate for the replacement of significant fluid loss, such as in cholera. The absorption of potassium and bicarbonate is maintained by the osmotic gradient in the intercellular space. Metabolic acidosis, usually associated with dehydration, can be safely corrected by this mechanism. The currently available ORT contains an appropriate amount of sodium, glucose, and other electrolytes and is of appropriate osmolality to maximize clinical efficacy [19].

The WHO, Centers for Disease Control (CDC), and the American Academy of Pediatrics (AAP) all support the use of ORT for some (mild–moderate) dehydration [8, 20, 21]. Rapid ORT in mild dehydration is done by giving 50 ml/kg over 4 hours. For moderate dehydration, 100 ml/kg can be given over the same duration. Generally, children being enterally rehydrated do not require blood tests.

**41**

*4.6.1 Resuscitation*

*Dehydration*

*DOI: http://dx.doi.org/10.5772/intechopen.83408*

Children who received oral ondansetron initially were less likely to be administered IV rehydration compared with those given placebo. In addition, both oral and IV ondansetron administration are associated with reduced rate of hospitalization [17]. Ondansetron is contraindicated in children with long QT syndrome, concomitant drugs that prolong QT, and to be used cautiously in children with heart disease.

Children can be discharged home when the following levels of recovery are achieved: satisfactory rehydration status as shown by clinical improvement, IV or NG fluids not required, and no significant losses. Adequate family education,

Inform about the expected natural course of the illness, prevention of transmission and looking at signs of dehydration. Encourage breastfeeding continuation in small babies, early refeeding, and the correct method of preparing ORS. Educate about the importance of giving anti-rotavirus vaccination and of course not to use

Nasogastric route is a safe rehydration technique with minimal adverse effects which has been adequately studied. Many clinical trials showed this method to have similar efficacy compared to IV therapy. Rapid NG rehydration using gastrolyte, 50 ml/kg for fluid deficit replacement over 4 hours, appears to be appropriate for children with mild-to-moderate dehydration [22]. If nasogastric rehydration is required beyond 4 hours, check urea and electrolyte concentration (UEC) and blood glucose level (BGL), and reassess the patient for hydration status.

Intravenous rehydration should be reserved for patients with severe dehydration or shock and for those with some (mild-to-moderate) dehydration who fail ORT. Fluid containing not less than 0.9% sodium chloride is preferred for rehydration [23, 24]. Using hypotonic fluids predisposes for dilutional hyponatremia due to excess antidiuretic hormone (ADH) secretion in children with AGE. Serum electrolytes and BGL are required in children with severe dehydration and/or requiring IV

The WHO recommends IV rehydration to be rapidly completed over 3–4 hours [8]. Rapid replacement of ECF improves gastrointestinal and renal perfusion, allowing earlier oral intake and a faster correction of electrolyte and acid-base abnormalities, which results in excellent recovery rate and decreased length of stay in ED [25].

Resuscitate shock/near shock with a prompt intravenous infusion of 20 ml/kg of 0.9% sodium chloride solution or Ringer's lactate solution as fast as possible. Reassessing and repeating boluses given, as necessary, are required until the patient

is recovered from shock and then followed by maintenance IV fluids [26].

proper instructions, and medical follow-up should be provided.

**4.2 Ondansetron to facilitate ORT**

**4.3 Discharge criteria**

**4.4 Patient/parent education**

unnecessary medication in simple AGE.

**4.5 Other rehydration methods**

**4.6 Intravenous (IV) rehydration**

fluid therapy for correction of dehydration.
