GIT

DIARRHOEA in INFANCY & CHILDHOODBy

Objectives of Lec.2

TYPES OF DEHYDRATION

TYPES OF DEHYDRATION
ISOTONIC (ISONATRAEMIC). S . Na145-135 = mmol/L HYPERTONIC (HYPERNATRAEMIC). S . Na > 145 (150) mmol/L HYPOTONIC(HYPONATRAEMIC). S . Na < (135)130 mmol/L.

CORRECTION OF DEHYDRATION

ORAL REHYDRATION THERAPY

ORAL REHYDRATION THERAPY

Mild to moderate dehydration from diarrhea of any cause can be treated effectively using a simple, oral rehydration solution (ORS) containing glucose and electrolytes. The ORS relies on the coupled transport of sodium and glucose in the intestine (Facilitated transport of SODIUM by absorption of GLUCOSE ) ORT is less expensive than IV therapy and has a lower complication rate. IV therapy still may be required for patients with severe dehydration; patients with uncontrollable vomiting; patients unable to drink because of extreme fatigue, stupor, or coma; or patients with gastric or intestinal distention.

Physiologic Basis of ORT

ORS
NaCl: 3.5 gm NaHCO3: 2.5 gm KCl: 1.5 gm Glucose: 20 gm Add 1 Liter of pure water

ORS ( WHO 2005)

[Na] 75mmol/L [Cl] 65mmol/L [HCO3] 10mmol/L [K ] 20mmol/L Glucose 13.5 g/L Osm 245 mosm/L

Choices of ORS

ORT
REHYDRATION PHASE For MILD Dehydration : 50 cc /Kg/ 4 Hr. For MODERATE Dehydration: 100 cc /Kg/ 4 Hr MAINTENANCE PHASE MILD Diarrhea : 100 cc /Kg/24HrSEVERE Diarrhea : 10-15 cc /Kg/ Hr in addition to milk feeds until diarrhea stops.

INTRAVENOUS REHYDRATION

ONGOING LOSS
MAINTENANCE
INTRAVENOUS REHYDRATION
DEFICIT

DEFICIT

Calculated According to The Clinical Assessment For Severity of Dehydration
Water Deficit


Calculation of Deficit Water

Resuscitation Phase

The child with dehydration requires acute intervention to ensure that there is adequate tissue perfusion. This resuscitation phase requires rapid restoration of the circulating intravascular volume. This restoration should be done with an isotonic solution, such as normal saline or Ringer's lactate. Blood is an appropriate fluid choice for a child with acute blood loss. The child is given a fluid bolus, usually 20 mL/kg of the isotonic solution, over about 20 minutes. A child with severe dehydration may require multiple fluid boluses and may need to receive fluid at a faster rate. The initial resuscitation and rehydration is complete when the child has an adequate intravascular volume. Typically the child has some general clinical improvement, including a lower heart rate, normalization of the blood pressure, improved perfusion, and a more alert affect. Potassium is not usually included in the intravenous fluids until the patient voids.

NOTE

The resuscitation phase (treatment of shock state ) is same in iso, hypo, & hypernatremic dehydration

MAINTENANCE

Maintenance fluids are composed of a solution of water, glucose, sodium potassium, and chloride. This solution replaces electrolyte losses from the urine and stool and water losses from the urine, stool, skin, and lungs. The glucose in maintenance fluids provides approximately 20% of the normal caloric needs of the patient. This percentage is enough to prevent the development of starvation ketoacidosis and diminishes the protein degradation that would occur if the patient received no calories. Glucose also provides added osmoles, avoiding the administration of hypotonic fluids, which may cause hemolysis.

Maintenance fluids do not provide adequate calories, protein, fat, minerals, or vitamins. Because of inadequate calories, a child on maintenance IV fluids loses 0.5% to 1% of real weight each day. Patients should not remain on maintenance therapy indefinitely; parenteral nutrition should be used for children who cannot be fed enterally for more than a few days. Parenteral nutrition is especially important in a patient with underlying malnutrition.

Goals of Maintenance Fluids

Body Weight Method for Calculating Daily Maintenance Fluid Volume
First 10 Kg 100 cc /Kg/24Hr Second 10 Kg 50 cc /Kg/24Hr > than 20 Kg 20 cc /Kg/24Hr NOTE: The maximum total fluid per day is normally 2,400 mL.

Maintenance requirements of electrolytes:

Sodium: 2 - 3 mEq/kg/day Potassium: 1 - 2 mEq/kg/day.


Composition of Maintenance fluids:

ONGOING LOSSES

Calculated CC for CC and mmol for mmol and added to the rehydrating solution. Replacement solutions should have approximately the same electrolyte composition as the fluid that is lost. Electrolyte content can be measured directly, or a solution can be selected based on the typical electrolyte composition of diarrhea or gastric losses

REPLACEMENT OF LOSSES

Fluid Management of Dehydration

TYPES OF IV FLUID

solution
Glucose (g/l)
Na+
K+
Ca+2
Cl-
Lactate
D5W
50
0
0
0
0
0
D10w
100
0
0
0
0
0
NS
0
154
0
0
154
0


0
77
0
0
77
0

0
38.5
0
0
38.5
0
D5NS
50
154
0
0
154
0


50
77
0
0
77
0
0.2 NS
0
31
0
0
31
0
3%NaCl
0
513
0
0
513
0
LR
0
130
4
3
109
28

HYPONATREMIC DEHYDRATION

HYPONATREMIC DEHYDRATION
Hyponatremic dehydration produces more substantial intravascular volume depletion due to the shift of water from the extracellular space into the intracellular space. In addition, some patients have symptoms, predominantly neurologic, as a result of hyponatremia

Treatment

Treatment of hypovolemic hyponatremia requires administration of IV fluids with sodium to provide maintenance requirements and deficit correction and to replace ongoing losses Most patients with hyponatremic dehydration do well with the same basic strategy for correction of Isonatremic dehydration.

The initial goal in treating hyponatremia is correction of intravascular volume depletion with isotonic fluid (NS or LR). An overcorrection in the serum sodium concentration (>135mMol/L) is associated with an increased risk of central pontine myelinolysis (CPM).

The risk of CPM also increases with overly rapid correction of the serum sodium concentration, so it is best to avoid increasing the sodium by >12 mEq/L each 24 hr.

Emergency treatment of symptomatic hyponatremia, such as seizures, uses IV hypertonic saline to increase the serum sodium concentration rapidly, which leads to a decrease in brain edema. Each 1 ml/Kg of 3% sodium chloride increases the serum sodium by approximately 1 mEq/L. A child often improves after receiving 4 to 6 mL/kg of 3% sodium chloride. The aim should be to increase the serum sodium concentration to not more than 130 mEq/L.

HYPERNATREMIC DEHYDRATION

Hypernatremic dehydration is the most dangerous form of dehydration due to complications of hypernatremia and of therapy.

Hypernatremia can cause serious neurologic damage, including central nervous system hemorrhages and thrombosis. This appears to be secondary to the movement of water from the brain cells into the hypertonic extracellular fluid, causing brain cell shrinkage and tearing blood vessels within the brain


Clinical Manifestations
Children with hypernatremic dehydration often appear less ill than children with a similar degree of isotonic dehydration. Urine output may be preserved longer, and there may be less tachycardia. Children with hypernatremic dehydration are often lethargic and irritable when touched. the pinched abdominal skin has a "doughy" feel. Hypernatremia may cause fever, hypertonicity, and hyperreflexia. More severe neurologic symptoms may develop if cerebral bleeding or thrombosis occurs.

Treatment

Too rapid treatment of hypernatremic dehydration may cause significant morbidity and mortality.

Idiogenic osmoles are generated within the brain during the development of hypernatremia. These idiogenic osmoles increase the osmolality within the cells of the brain, providing protection against brain cell shrinkage secondary to movement of water out of cells into the hypertonic ECF. They dissipate slowly during correction of hypernatremia.

With rapid lowering of the extracellular osmolality during correction of hypernatremia, there may be a new gradient created that causes water movement from the extra-cellular space into the cells of the brain, producing cerebral edema. Symptoms of the resultant cerebral edema can produce seizures, brain herniation, and death.

To minimize the risk of cerebral edema during correction of hypernatremic dehydration, the serum sodium concentration should not decrease more than 12 mEq/L every 24 hours. The deficits in severe hypernatremic dehydration may need to be corrected over 2 to 4 days the initial resuscitation-rehydration phase of therapy remains the same as for other types of dehydration.


Seizures are the most common manifestation of cerebral edema from an overly rapid decrease of the serum sodium concentration during correction of hypernatremic dehydration Acutely, increasing the serum concentration via an infusion of 3% sodium chloride can reverse the cerebral edema.

Monitoring Therapy

ANTIMICROBIALS
Campylobacter Erythromycin Clostredia difficle Vancomycin, Metronidazol Salmonella Amp, TMP-SMZ, Chloram,3rd GCS Shigella Co-TMZ,Nalidixic acid, 3rd GCS V cholerae Tetracycline,Co-TMZ G lambilia Metronidazole E histolytica Metronidazole
DRUG THERAPY



Nitazoxanide, an anti-infective agent, has been effective in the treatment of a wide variety of pathogens including G. lamblia, E. histolytica, C. difficile, and rotavirus. Although preliminary data suggest that nitazoxanide may be of use in nonspecific acute secretory diarrhea, these data need replication in further studies.

Medications that slow gut motility diphenoxylate, loperamid & anticholinergics are COTRAINDICATED

Racecadotril, an enkephalinse inhibitor, has inconsistently been shown to reduce stool output in patients with diarrhea. Experience with this drug in children is limited, and for the average child with acute diarrhea it may be unnecessary.

probiotic

The use of probiotic nonpathogenic bacteria for prevention and therapy of diarrhea has been successful in developing countries. In addition to restoring beneficial intestinal flora, probiotics can enhance host protective immunity. A variety of organisms (Lactobacillus, Bifidobacterium) have a good safety record.

Enteral Feeding and Diet Selection

Continued enteral feeding in diarrhea aids in recovery from the episode, and a continued age-appropriate diet after rehydration is the norm. Once rehydration is complete, food should be reintroduced while oral rehydration can be continued to replace ongoing losses from emesis or stools and for maintenance. Breast-feeding or nondiluted regular formula should be resumed as soon as possible. Foods with complex carbohydrates (rice, wheat, potatoes, bread, and cereals), lean meats, yogurt, fruits, and vegetables are also tolerated. Fatty foods or foods high in simple sugars (juices, carbonated sodas) should be avoided.

COMPLICATIONS

Renal Failure Dehydration Acute Tubular Necrosis Haemolytic-Uraemic Synd. Renal Vein Thrombosis Hypokalaemia and Paralytic Ileus. Secondary Lactose Intoleranc Fluid Overload and Pulmonary Edema

Convulsions Fever. Hypoglysemia. Hypocalcemia. Hyponatremia. Hypernatremia. Hypomagnesemia. Meningitis. Cerebral Vascular Thrombosis.

Prevention

Promotion of Exclusive Breast-feeding Improved Complementary Feeding Practices Rotavirus Immunization Improved Water and Sanitary Facilities and Promotion of Personal and Domestic Hygiene Improved Case Management of Diarrhea