ACUTE GASTROENTERITIS AND FLUID MANAGEMENT

BROUGHT TO YOU BY PAEDIATRIC TEAM SPONSORED BY Dr F. Mokgoadi

Presentation outline

• Introduction and Epidemiology

• Aetiology

• Pathophysiology

• Signs and symptoms

• Work-up including Classification

• Management • Fluid and Electrolytes

• Feeding and Nutrition

• Prevention

Definitions and Terms:Acute Gastroenteritis (AGE): diarrheal disease of rapid

onset, with or without accompanying symptoms, signs, such as nausea, vomiting, fever, or abdominal pain

Diarrhea: the frequent passage of unformed liquid stools (3 or more loose, watery stool per day)

Dysentery: blood or mucus in stools

Diarrhea

• Acute: short in duration of < 7 days

• Persistent diarrhea: starts acutely and lasts longer than 1 week

Epidemiology

• One of the most common illness of infancy

• Second to respiratory illness as a cause of childhood deaths WW

• It represents a major cause of morbidity and mortality

• 3-10 episodes of diarrhea/year/subject in children <5 yrs and decreases to < 1 for children >5

• Deaths are usually a result of dehydration but malnutrition plays an important role as it increases the incidence and severity of diarrhea

• By 3 years, virtually all children become infected by the most common agent

Aetiologies

• AGE is a clinical syndrome produced by a variety of Viral, Bacterial and Parasitic enteropathogens.

• AGE is almost entirely caused by infections acquired through fecal-oral route, but ingestion of contaminated food or water also plays a role

• We have: Non-enteric, Non-infectious and Infectious causes of the Gastro-intestinal tract

• Episodes usually last 5-10 days

Causes of acute diarrhoea in infancy and childhood

Non-enteric causes: otitis media. Meningitis, sepsis generally

Non-infectious causes: milk/food allergies, drug side effects, malabsorption

Infections of the gastrointestinal tractViral

Bacterial

Protozoal

Common infectious causes of AGE

Viral

Rotavirus

Enterovirus, Calicivirus

Adenovirus, Astrovirus

Bacterial

E.Coli, Shigella

Salmonella, Campylobacter

C.difficile, V. Cholera

parasitic

• Entamoeba Hystolitica

• Giardia lamblia

• Cryptosporidium

Aetiolgy cont

• Rotavirus is known to be the most common pathogen in children

• It is more severe than other causes and more often results in dehydration, Hospitalization, Shock, Metabolic disturbances and Death

• Bacterial pathogens are more common where poor sanitation, hygiene and water supply play a role causing dysenterey

PathophysiologyThe 2 primary mechanisms

(1) Damage to the villous brush border of the intestinemalabsorption of intestinal contents an osmotic diarrhea

(2) Release of toxins that bind to specific enterocyte receptorsrelease of chloride ions into the intestinal lumensecretory diarrhea

Pathophysiology

• Rotavirus attach and enter mature enterocytes at the tip of the small intestinal villi

• Cause structural changes to the bowel mucosa, including villous shortening and mononuclear inflammatory infiltrates in the lamina propria

• This virus induce maldigestion of carbohydrates and their accumulation in the intestinal lumen (in the absence of lactase)

• Malabsorption of nutrients and concomitant inhibition of water reabsorption can lead to a malabsorption component of diarrhea

• Rotavirus secretes an enterotoxin, NSP4 which leads to a calcium-dependent chloride secretory mechanism

Sign & Symptoms•Nausea & Vomiting •Diarrhea • Loss of appetite • Fever •Headaches • Abdominal pain • Abdominal cramps • Bloody stools •Dehydration • Lethargic

• Vomiting is largely attributed to local factors and poor gastric emptying, and should not be treated with antiemetic drugs

• Abdominal pains are usually spasmodic due to disordered motility or is associated with colitis in dysentery

• Diarrhea is the manifestation of secretion or absorption disturbance and disordered motility, a symptom of damage already done in the infected gut.

clinical assessment of Hydration

• Recognize poor perfusion and other signs of shock• Cold peripheries

• Depressed LOC

• Increase capillary refill time (>3sec)

• Poor/weak peripheral pulses

• Reduced urine-output

• signs of dehydration.docx

Work-up

• After resuscitation, in children with severe dehydration, shock or other signs of metabolic, nutritional or other co-morbidities• Electrolytes and serum acid base determination

• All severely dehydrated patients, mod dehydration with an atypical presentation, malnourished children

• Blood glucose disturbances occur in severely ill patients as a result of glycogen depletion with lack of intake, or associated with the stress response of dehydration

Electrolyte disturbances

• Large amounts of Sodium are lost in diarrheal stools

• In acidosis, a shift of intracellular potassium to EC compartment results in a spurious elevation of the serum level despite intracellular potassium loss

• Give K+ to all patients with severe diarrhea until dehydration and acidosis are corrected

• Sodium disturbances occur frequently

• Sodium content of the stool water varies from plasma-like in secretory diarrhea , to very low in pure Osmotic diarrhea

Fluid and electrolyte management

First treat SHOCK if present

• Always SHOUT for HELP• A…….B…..• Circulation

• Establish vascular access or IO if failed venous access after 2 good attempts• Give 20ml/kg of R/L or Normal Saline rapid infusion or 5ml/kg in aliquots X4 is much

safer• Watch for signs of circulatory overload i.e hepatomegaly, gallop rhythm or basal

crackles, puffiness of the eyelids, tachy-pnoea and –cardia. • Repeat R/L 20ml/kg if patient is still shocked. Re-assess and give more if still shocked

• Don’t-Ever-Forget-Glucose• Re-assess ABC and response so far• Give 1st dose Ceftriaxone 80mg/kg stat to cover sepsis

Treating Shock in severely Malnourished

• ABC still as essential as the normally nourished patients

• Give 15ml/kg infusion over 30 minutes

• Re-assess and repeat if still shocked

• Give up to 4 boluses and thereafter, T/F to HC or ICU

• Patient response should guide further fluid therapy

• When shock has been treated successfully, proceed to the management of dehydration.

• But remember your patient can go back into shocked if improperly rehydrated

Rehydration fluids

• Its NB to use solutions with sufficient Na conc. To prevent Hyponatremia

• ½ DD is appropriate if IV route is used, or ORS for enteral replacements

• Where vomiting is the main source of fluid loss, rehydration fluid (0.45%NaCl and 5% Dextrose) with added K is appropriate

• Dose of ½ DD or ORS for rapid rehydration over 4 hours• Some Dehydration: 50ml/kg over 4 hrs (12.5ml/kg/hour)• Severe Dehydration: 100mls/kg/4hours (25mls/kg./hour)

• Rapid rehydration over 4hrs should not be used in severe malnutrition, cardiac failure, severe pneumonia, encephalopathy etc.

• However, rehydrate over 24hours or even 48 hours

• APPROPRIATE RESPONSE AT 4.docx

• Severely malnourished have a deficient K and elevated Na levels, thus require a special ORS: ReSolMal

Maintenance fluids

• Should be given enterally wherever possible but intravenously where nil per Os is absolute

• Fluid restriction to approximately 50-60% of maintenance should be adhered to, where there is a risk of inadequate secretion e.g in Renal failure

• NORMAL MAINTENANCE FLUID REQUIREMENTS.docx

Never forget the ongoing losses

• Losses need to be replaced by equal volumes of fluids of similar composition

• For moderate losses, add 30mls/kg to maintenance requirements. But give more if there’s a need

• For those taking enterally: • <2years: 50-100mls AELS• >2years: 100-200mls AELS

• Small frequent volumes of home based sugar salt solution as little as 5mls every minute, can be effective in preventing dehydration even in vomiting cases

• Continue Breast feeding and oral feeding once perfusion is restored

What else might help?

• Zinc: reduces the duration and severity of diarrhea

• Antimotility agents like loperamide are C/I due to potentially serious side effects (malignant hyperpyrexia, lethargy and dystonia)

• Vit A: reduces the severity of diarrhea, but do not give if a dose was given in the previous month

• All children with diarrhea get vit A and Zinc according to age

• Other drugs, Any use?

Electrolyte abnormalities

• Hypokalemia (<3): even when the serum K conc. Is normal, these patients have a depletion of the total body potassium

• Plasma k level doesn’t always provide an accurate est of total body deficit. There may be K shift from intracellular space to the plasma.

• <3mmol/l: stat dose oral K <5kg= 250mg. 5-10kg=500mg and >10kg=1g stat• Ongoing losses: < 5kg: 125mg, 5-10kg:250mg and >10kg: 500mg tds

• Re-assess after 4 hours

• Stop when abnormal losses stop

Hypokalemia

K<2>1.5

• Attach ECG: prolonged QT and Flat T waves

• Give stat doses as previous slide

• Oral KCl: 100mg/kg 6hrly with max dose 3g/day

• Plus IV correction• Add to iv fluids (200mls): ½ DD=2ms

15%KCl, Saline=4mls 15%KCl• Recheck in 4hrs and manage

accordingly

K<1.5: paralysis, muscle weakness,apnoea• Admit to HC/ICU• Give stat dose accordingly• Oral K: 100mg/kg 6hrly• Plus IV correction• If ICU: 0.3mml/kg in 50mls N saline

via C.Vein over 1hour• Recheck in 2hours• Manage ongoing losses and

replacement

Hyponatremia Na<135mmol/l

Mild symptomatic (120-130)

• Evaluate pt: if euvolemic, manage underlying illness

• Dehydrated: rehydrate over 24-48 hours

• Recheck electrolytes 4hourly, manage ongoing losses

Severe symptomatic (<120)

• ABC

• Stop seizures (iv phenobarb10mg/kg)

• Single dose Hypertonic saline infusion over 1 hour (formula)• 4ml/kg 3% saline

• Re-check electrolytes in 1 hour

• Manage on-going losses

©2011 MFMER | slide-28

References

• Handbook of Paediatrics 7th edition pg 121-129, 461-481

• Std Rx guidelines and Essential Medicines List 2013 (Dept ofHealth) pg 2.9-2.17

• Gastroenteritis presentation by Prof T Rogers Dept of Clinical Microbiology

• South African medical journal, vol 102,no.2 2012 (Management guidelines for Acute infective diarrhea in infants) prof F Wittenburg

• Acute gastroenteritis in children by Dr Alta Terblanche, Professional Nursing Today 2010

©2011 MFMER | slide-30

Anyone Ophidiophobic?

©2011 MFMER | slide-31