【儿科学】(下载)6.2 腹泻病与液体疗法

water > Na+
disorder
acute
malnutrition
fever, given
diarrhea
given glucose only free water
main symptom
circulation
CNS
Electrolytes and acid-base disturbance
Degree of dehydration
mild
moderate
severe
loss of fluid
5% (50 ml/ kg) 10% (100 ml/ kg) 15%
skin
slightly dry
dry, delayed
very delayed
capillary refill
mucous membranes slightly dry
Importance of Diarrhea
In under five children
Diarrhea is a leading cause of:
Malnutrition Morbidity Mortality
Infantile diarrhea
begin self-limited condition, subside within a few days < 2y, 50% < 1y clinical presentation and course of illness:
delivery to the tissues lactic acidosis ❖ kidney hypoperfusion urine output excretion acid
Metabolic acidosis
Clinical manifestation: lethargic, pale, compensatory hyperventilation increased respiratory effort
gluconeogenesis
blood dilution
K＋shift back to cell
Hypokalemia
II. Hypocalcemia and hypomagnesemia
Causes: poor intake, malabsorption, increased loss Clinical manifestations: asymptomatic, neuromuscular
feeding problems milk allergy malabsorption: disaccharidase deficiencies, CF… climate factors anatomic defects: malrotation, microvillous atropy… molitity disorders laxative abuse etc
Diarrhea: imbalance in the intestine handling of water and electrolytes
Adults: small intestine: absorb 10 ~ 11 L / day a
combination of ingested and secreted fluid colon: 0.5 L / day
3. according to mechanisms
primary mechanism secretory diarrhea
osmotic diarrhea
motility diarrhea increased motility decreased motility
invasive diarrhea
irritability, tetany Symptoms of tetany may be provoked when dehydration
and acidosis are corrected ( ionized Ca++)
III. Metabolic acidosis: causes
❖ Loss of bicarbonate from the body ❖ Poor intake, malabsorption starvation ketoacidosis ❖ Dehydration hypoperfusion inadequate oxygen
irritable/ lethargic very sick
Type of dehydration
isotonic
hypotonic
hypertonic
incidence 70~80 %
10~15 %
10~20%
[Na+]mmol/L 130 ~ 150 <130
>150
losses
Na+ = water Na+ > water
defect
absorption secretion electrolyte transport maldigestion, transport defects, ingestion of unabsorbable solute
transit time defect in neuromuscular unit(s) stasis (bacterial overgrowth) inflammation, mucosal surface area and / or colonic reabsorption motility
diarrhea
intestinal transit
disturbance of fluid，
electrolytຫໍສະໝຸດ Baidus
Infantile diarrhea
Etiology Pathogenic mechanism Type of diarrhea Clinical aspects Diagnosis Treatment
Infantile diarrhea
Etiology Pathogenic mechanism Type of diarrhea Clinical aspects Diagnosis Treatment
virus
bacteria
food induced
villi damage
toxigenic
invasive
undigested and unabsorbed food, digested by resident microflora
organic acid
transport system intestinal secretion
mucosa erosions and
osmotic force
ulceration
I. clinic aspects of hypokalemia
K+ < 3.5mmol/L abdominal distension muscle weakness, paralysis, tendon reflex (-) bluntness of heart tone, arrhythmia, etc EKG：U wave, depressed ST segment, flat or inverted
T wave
dehydration
vomiting, diarrhea
poor intake
[K+]
＋
acidosiKs ＋shift from intercellular to plasma
[K+]
rehydration
diuresis corrected acidosis
mild or no hypokalemia
hypokalemia, acidosis, etc
dehydration
degree of dehydration
mild dehydration moderate dehydration severe dehydration
type of dehydration
isotonic dehydration hypotonic dehydration hypertonic dehydration
structural lesions, enzymatic deficiency
abnormality of the glucose-sodium
toxin (LT, ST)
invade and
epithelial cells proliferate in
epithelia cells
cAMP
cGMP
dry
highly dry
fontanel, eyeballs slightly depressed sunken
very sunken
tears, uresis
anuria, no tear
circulation
warm
cool, pale
cold, mottled
general condition still well
Infantile Diarrhea
Usual stool output is 10 g/kg/d in children and 200 g/d in adults.
Diarrhea is increased water in stool, resulting in increased stool frequency or loose consistency.
depending on the host depending on the infecting organisms
Infantile diarrhea
Etiology Pathogenic mechanism Type of diarrhea Clinical aspects Diagnosis Treatment
Infantile diarrhea
Etiology Pathogenic mechanism Type of diarrhea Clinical aspects Diagnosis Treatment
IV. Clinical aspects
stool movements stool characteristics
mild < 10 /d loose
systemic
less
manifestations disturbance of fluid mild
and electrolytes
severe diarrhea > 10 /d watery, mucousy appetite , vomiting
energy , fever, etc moderate-severe dehydration
➢ Enteral infections:
bacteria: E. coli, Campylobacter jejuni, Salmonella, Yersinia, S. aureus, etc
virus: rotavirus, enteric adenovirus, astrovirus, Norwalk virus, etc
Laboratory tests: pH↓, SB↓, CO2-CP↓
Rotavirus diarrhea
III. Type of diarrhea
1. according to clinical course Acute：< 2 w Persistent：2 w～2 m Chronic：> 2 m
2. according to disease intensity mild diarrhea severe diarrhea
I. Etiology
Immature of digestive, neurologic system poor modulation of GI quick growth, burden of GI
lower SIgA
immature intestinal flora (neonate)
Inflammatory diarrhea
Fungi: candida albicans parasites: giardia lamblia, etc
➢ Parenteral infections:
urinary tract infection, pneumonia, tympanitis, meningitis, etc
Non-inflammatory diarrhea