13.Starvation

Starvation

Definition of Starvation

Starvation is defined as the continuous deprivation of food and water necessary for the maintenance of life. It can manifest in two forms:

• Acute Starvation: This refers to complete deprivation of food and drink over a continuous period, leading to rapid physiological changes and health deterioration.

• Chronic Starvation: This involves a long-term deficiency in the quantity and quality of food, also known as partial starvation or malnutrition, where the body lacks essential nutrients for proper functioning.

Pathophysiology of Starvation

The immediate physiological response to starvation involves a series of metabolic adaptations:

1. Initial Energy Source: The body utilizes glycogen stores within the first 24 hours of starvation.

2. Shift to Lipolysis: As glycogen is depleted, the body shifts its primary energy production to lipolysis, where adipose tissue breaks down fat into free fatty acids.

   • These free fatty acids serve not only as fuel but also as substrates for the synthesis of ketone bodies, which become crucial metabolic fuels for the muscles and brain during prolonged starvation.

   • Plasma levels of free fatty acids and ketone bodies increase during starvation and can be detected in urine.

3. Fat Reserves: The last fat reserves to deplete are typically located in the buccal fat pads (Bichat's fat pads).

4. Energy Depletion Sequence: In acute starvation, carbohydrates are depleted first, followed by fats, and lastly proteins in a process referred to as muscle wasting.

Signs and Symptoms of Acute Starvation

The progression of symptoms in acute starvation includes:

• Initial Symptoms: The onset includes hunger pangs and pain, extreme thirst, generalized weakness, and difficulty concentrating on tasks.

• Day 2 Symptoms: Symptoms intensify with pronounced hunger pains, leading to irritability and restlessness.

• By Day 3: Individuals may experience constipation and oliguria (decreased urine output) alongside an increased frequency of micturition. Physiological changes include:

  • Decrease in blood sugar, blood pressure, pulse rate, and cholesterol levels.

  • Weakened pulse and a potential increase in heart rate (tachycardia) upon physical exertion.

• Day 4 Symptoms: Marked weight loss occurs—up to 40% weight loss can lead to fatal consequences. Physical indicators include:

  • Severe emaciation, loss of subcutaneous fat, and sunken eyes.

  • Additional symptoms include extremely dry skin and lips, scanty and thick saliva, lesions on the tongue, muscle cramps, and significant muscle wasting by days 6-7.

  • Urine becomes scanty, highly concentrated, with a strongly acidic reaction.

• Severe Starvation Effects: As severe starvation progresses, individuals may become unable to walk or speak, and experience fluctuating body temperatures which indicate worsening physiological stress.

Causes of Death in Starvation

The leading cause of death related to starvation is cardiac failure, which results from the heart's inability to cope with the stress of prolonged deprivation. Other causes include:

• Persistent neurological deterioration leading to unconsciousness or respiratory failure.

• Increased risk of intercurrent infections and hepatorenal failure, where the liver and kidneys fail simultaneously due to the inability to regenerate or perform their functions effectively.

Fatal and Survival Periods

• Without Food/Water: Acute starvation can be fatal within 10-12 days without water.

• With Water Intake: Survival may extend to 6-8 weeks or longer, depending on environmental conditions, individual health, and body fat reserves.

Chronic Starvation

Characteristics of Chronic Starvation

Chronic starvation or malnutrition leads to substantial nutritional deficiencies, presenting with symptoms such as:

• Lack of proteins, vitamins, and minerals, leading to systemic failures.

• Common symptoms observed include:

  • Anemia, especially iron-deficiency anemia.

  • Emaciation and significant muscle wasting resulting in reduced strength.

  • Edema of the extremities due to protein deficiency (Kwashiorkor).

  • Frequent diarrhea, increasing susceptibility to dehydration and infections.

  • Overall reduced immunity increases the risk of contracting infections like pneumonia and tuberculosis.

Physiological Effects

Chronic starvation leads to several critical physiological changes:

• Loss of subcutaneous and visceral fat, leading organs to appear pale and undernourished.

• The liver can undergo centrilobular necrosis, leading to impairment of its detoxifying functions, and the gallbladder may become enlarged filled with thick bile, obstructing digestion.

• Intestinal walls become thin and translucent, signifying malabsorption issues.

• Generally, the rectum remains empty, reflecting a lack of nutritional substrate to process.

• The heart may exhibit brown atrophy—a sign of chronic undernutrition showing diminished contractility.

Neurological and Psychological Symptoms

As starvation progresses, terminal symptoms may include:

• Severe muscular pain throughout the body, exacerbated by muscle wasting.

• Mental health deteriorations, leading to hallucinations and potential convulsions, which can signify severe electrolyte imbalances.

Postmortem Findings of Starvation Death

Upon autopsy, noteworthy signs of death due to starvation include:

• An emaciated body with sunken eyes and pronounced facial bones,

• Lustreless hair and dry, cracked lips.

• Skin is pale, dry, and inelastic, exhibiting an early cadence of rigor mortis.

• Clear evidence of subcutaneous fat loss with an abdomen that becomes scaphoid (hollowed appearance).

Factors Influencing Fatality

Key Factors Affecting Starvation Survival

Several factors significantly influence survival durations during starvation:

• Age: Children and infants show higher vulnerability to starvation effects; older adults may exhibit greater resilience due to existing fat reserves and nutritional adaptations.

• Sex: Women may endure starvation longer than men due to higher body fat percentages, providing additional energy reserves.

• Body Condition: Individuals with higher body fat percentages tend to survive longer as they can utilize stored fat for energy.

• Environmental Conditions: Exposure to cold or extreme heat can hasten mortality due to increased energy expenditure managing thermoregulation.

• Intercurrent Infections: The presence of infections can significantly accelerate mortality rates, compounding the effects of starvation.

• Physical Exertion: Increased physical activity can exacerbate the adverse effects of starvation, leading to quicker energy depletion.

Autopsy Findings

Notable findings at autopsy indicative of starvation include:

• An emaciated physique with pronounced sunken eyes.

• Depletion of Bichat's fat pad and marked loss of general body fat reserves.

• Complete body fat depletion and translucency in small intestinal walls indicative of malabsorption due to prolonged disuse.

• Distended gallbladder filled with thick bile and evidence of brown atrophy in the heart.

• Organ atrophy commonly observed, excluding the brain which tends to retain certain functionalities despite the overall systemic breakdown.

Histopathological Observations

Histopathological changes noted in subcutaneous fatty tissues include:

• Gelatinoid atrophy and rarefaction of subepicardial tissue due to long-term nutrient deficiencies.

• Myocardial fibers may show signs of brown atrophy, while both pancreatic and endocrine tissues may undergo significant necrosis, impacting their functional capabilities.

Medicolegal Aspects

Medicolegal evaluations must differentiate deaths due to starvation from other causes of significant weight loss such as malignancy or infections. Consideration for instances of:

• Suicidal fasting versus starvation requiring public attention (e.g., participation in religious practices such as Jain ‘Santhara’ or manifestations of mental illness).

• Historical contexts reflect harsh realities involving starvation as a mode of execution in ancient societies and instances of genocide, such as those observed in concentration camps.