Dehydration and Leading Causes of Death

Dehydration

• Dehydration is a fluid deficit, characterized by altered fluid and electrolyte balance.
• Negative fluid balance and sodium imbalance are key indicators.
• Diarrheal illness is the leading cause of infant and child mortality.
• Water, electrolytes (sodium, chloride, potassium, bicarbonate) are lost through various routes, including stools, vomits, sweat, urine, and breathing.
• Children in developing countries are most susceptible to dehydration.

Leading Causes of Death

• The World Health Organization (WHO) identifies leading causes of death globally and in low-income countries.
• Data provided in the slides depict the leading causes for both.
• Data shows the leading causes for 2000 and 2019.

Dehydration Pathophysiology

• Dehydration affects both extracellular fluid (ECF) and intracellular fluid (ICF) compartments.
• Causes of dehydration include decreased fluid intake, increased fluid output (e.g., excessive diuresis, gastrointestinal loss, insensible losses like sweating), and fluid shifts (e.g., ascites, capillary leakage).
• The body's water balance is shown by diagrams illustrating how water is gained and lost, including through food, metabolism, faeces, sweat, and the lungs.

Dehydration Classifications

• Dehydration is categorized based on blood sodium concentration.
• Hyponatremia: low sodium.
• Isonatremia: proportional loss of volume.
• Hypernatremia: high sodium; loss not proportional.

Dehydration Clinical Manifestations

• Increased thirst, dry skin and mucous membranes, decreased/absent tears, changes in vital signs (e.g., increased respiratory rate, decreased blood pressure, and weak pulse), increased body temperature, prolonged capillary refill time, weight loss, depressed fontanelle, poor tissue turgor, dark sunken eyes, decreased level of consciousness, decreased/absent urine output are clinical signs.

Severe Dehydration

• Two or more signs including lethargy/unconsciousness, sunken eyes, inability to drink, and a slow return of skin turgor (≥2 seconds) indicate severe dehydration.

Some Dehydration

• Two or more signs including restlessness/irritability, sunken eyes, and eager drinking/thirst indicate some dehydration.

Dehydration Diagnosis

• History and physical examination are essential.
• Fluid intake/output (volume and type).
• Laboratory analyses in severe cases, including blood electrolyte concentrations, bicarbonate (acid-base balance), and anion gap.
• Kidney function is assessed through blood urea nitrogen (BUN), serum creatinine, and specific gravity (urine osmolality), which indicates the kidney's ability to excrete/conserve water via assessment of concentrated/diluted urine levels and the specific gravity of urine.

Dehydration Treatment

• Mild/Moderate: Oral rehydration with fluids containing sodium, potassium, and glucose in appropriate proportions, and frequent, small amounts.
• Severe: Intravenous administration of Ringer's lactate or isotonic saline, matching the patient's plasma concentration, and large-volume fluid replacement.
• Rapid correction of hyponatremia and hypernatremia should be avoided due to potential complications.

Types of Fluid Solutions

• Isotonic solutions have the same tonicity as plasma, distributing equally among intravascular, interstitial, and intracellular spaces.
• Hypotonic solutions have lower tonicity than plasma, causing fluid movement from intravascular to interstitial and intracellular spaces.
• Hypertonic solutions have higher tonicity than plasma, moving fluid from interstitial and intracellular to intravascular spaces.

Dehydration Clinical Snapshot

• A flowchart summarizing the process of dehydration identification and management.
• Includes assessments of fluid intake, response to thirst, causes of fluid loss (e.g., vomiting, diarrhea, diabetes), fluid shifts, and appropriate treatment methods.