Natural Disasters: Complete Notes for BSc Trauma & Emergency Students

Natural disasters are events triggered by natural hazards that cause serious disruption, injury, illness, death, displacement, infrastructure damage, and increased demand on emergency medical systems. For BSc Trauma and Emergency Care students, understanding natural disaster management is essential because these events create mass casualties, damage roads and hospitals, interrupt communication, increase infection risk, and expose ambulance crews to dangerous environments , , , . Emergency response and recovery workers must prepare for the hazards they may encounter while responding to natural disasters .

Key Terminology

Hazard — a potentially damaging event or condition such as an earthquake, flood, cyclone, landslide, wildfire, or lightning .

Exposure — people, buildings, roads, hospitals, and ambulances located in a hazard-prone area. For example, houses built near rivers or coastal settlements exposed to cyclones .

Vulnerability — the tendency of people or systems to be harmed. CDC disaster epidemiology resources emphasize that at-risk and socially vulnerable populations require special attention during disasters . Poor housing, poverty, children, the elderly, pregnant women, people with disabilities, and those with chronic illness all have higher vulnerability .

Capacity — the ability of individuals, communities, EMS, hospitals, and government systems to reduce risk and respond effectively. Examples include trained ambulance staff, disaster plans, early warning systems, evacuation shelters, and stocked emergency supplies .

Preparedness — actions taken before a disaster to reduce harm. CDC's all-hazards preparedness guidance includes planning evacuation routes, practicing emergency plans, and knowing how local authorities will notify the public during emergencies .

Classification of Natural Disasters

Category	Examples	Main Emergency-Care Concern
Geophysical	Earthquake, volcanic eruption, tsunami	Trauma, crush injury, burns, drowning
Hydrological	Flood, flash flood, landslide, avalanche	Drowning, trauma, hypothermia, contamination
Meteorological	Cyclone, hurricane, tornado, thunderstorm, lightning	Trauma, electrocution, drowning
Climatological	Heat wave, cold wave, drought, wildfire	Heat stroke, hypothermia, dehydration, burns
Secondary biological risk	Post-flood outbreaks, vector increase	Diarrhea, leptospirosis, malaria, dengue

WHO guidance on research methods for health emergency and disaster risk management recognizes these broad categories, noting that disasters often follow a hazard that negatively impacts a population .

General Health Effects of Natural Disasters

Immediate: Death, severe bleeding, fractures, head and spinal injuries, crush injury, drowning, burns, electrocution, hypothermia, heat stroke, and psychological shock.

Early (days to weeks): Wound infection, dehydration, diarrhea, respiratory infections, snake bite, exacerbation of chronic disease, missed dialysis or insulin, lack of oxygen supply, pregnancy-related emergencies, and acute stress reaction.

Late (weeks to months): Malnutrition, vector-borne disease, post-traumatic stress disorder, depression, anxiety, disability, and poor sanitation-related illness.

General Principles of EMS and Ambulance Response

Scene safety first. The first rule is: do not become a victim. CDC specifically notes that natural disasters and extreme weather events can expose responders to hazards, and response workers should prepare for risks they may encounter . Key responder hazards include floodwater, collapsed structures, aftershocks, unstable slopes, fire and smoke, downed electrical wires, contaminated water, chemical contamination, heat stress, cold exposure, sharp debris, violence, poor visibility, and damaged roads .

Disaster Response Sequence

1. Alert received → Confirm location and type of disaster → Ensure crew safety and PPE → Move to safe staging area → Establish command and communication → Scene size-up → Triage → Life-saving treatment → Transport by priority → Hospital notification → Documentation and reassessment

Incident command requires a clear chain of command, typically: Incident Commander → Operations → Medical/EMS Branch → Triage Unit, Treatment Unit, and Transport Unit. EMS responsibilities include triage, initial life-saving care, patient tracking, ambulance staging, hospital coordination, safe transport, communication with command, crew safety, and documentation.

Ambulance Staging

Ambulances should be parked in a safe staging area, not inside the danger zone. A good staging area is safe from the hazard, close enough for rapid access, large enough for multiple vehicles, connected to usable roads, easy to communicate from, away from crowd congestion, and controlled by a staging officer.

Patient Movement in a Disaster

Danger zone → Rescue → Casualty collection point → Primary triage → Treatment area → Ambulance loading area → Appropriate hospital

Disaster Triage

Triage is the sorting of patients according to urgency, survivability, and available resources. In disaster care, the goal is to do the greatest good for the greatest number.

Triage Color Coding

Color	Priority	Meaning	Examples
Red	Immediate	Life-threatening but treatable	Airway obstruction, severe bleeding, shock
Yellow	Delayed	Serious but can wait	Stable fracture, controlled bleeding
Green	Minor	Walking wounded	Minor cuts, sprain, emotional distress
Black	Dead/expectant	Dead or unlikely to survive with available resources	No breathing after airway opening

Simple Triage Flowchart

• Can the patient walk? Yes → GREEN. No → Check breathing.
• Breathing? No → Open airway. Breathing after airway opened? Yes → RED. No → BLACK.
• Breathing abnormal or severe distress? Yes → RED.
• Severe bleeding or shock? Yes → RED.
• Cannot follow commands? Yes → RED. No → YELLOW.

Common triage mistakes include transporting the first patient seen instead of the highest-priority patient, allowing green patients to crowd the ambulance loading area, not reassessing yellow patients, sending all patients to the nearest hospital, failing to record patient destination, and ignoring responder safety.

Earthquakes

An earthquake is sudden shaking of the ground due to movement of the earth's crust. Main hazards include building collapse, falling objects, road damage, fires, gas leaks, damaged electrical systems, landslides, tsunamis in coastal areas, and aftershocks. CDC emergency resources include earthquake preparedness and safety information as part of natural disaster and emergency preparedness guidance , .

Common injuries: crush injury, fractures, head injury, spinal injury, chest trauma, abdominal trauma, pelvic injury, lacerations, burns, suffocation, and dust inhalation.

Crush Syndrome

Crush syndrome is a life-threatening systemic complication of prolonged muscle compression. Pathophysiology: prolonged compression → muscle ischemia → muscle cell breakdown → release of myoglobin, potassium, and acids → reperfusion after rescue → hyperkalemia + acidosis + shock → acute kidney injury + arrhythmia.

Signs: history of prolonged entrapment, painful swollen limb, weakness or paralysis, dark urine, shock, reduced urine output, arrhythmias, and suspected hyperkalemia.

Prehospital management: ensure scene safety, do not enter unstable structures without rescue clearance, use helmet/gloves/boots/eye protection/dust protection, follow incident command, start triage outside the collapse zone, control bleeding, manage airway and breathing, give oxygen if indicated, immobilize suspected spine injuries, splint fractures, prevent hypothermia, start IV fluids for suspected crush injury if within scope and protocol, and transport to a trauma-capable hospital.

Exam pearls: Aftershocks can injure rescuers. Never rush into a damaged building without safety clearance. Crush syndrome may worsen after extrication. Fluids should be started early in suspected crush injury if protocol allows. Green patients should be separated early. Dust exposure can worsen asthma and respiratory disease.

Floods

A flood is overflow of water onto normally dry land. CDC provides public emergency resources on preparing for floods, staying safe during floods, and protecting health after floods , .

Types: river flood, flash flood, urban flood (waterlogging due to heavy rain and poor drainage), coastal flood (sea water pushed inland by storm surge), and dam-break flood.

Main hazards: drowning, fast-moving water, hidden drains and manholes, electrocution, contaminated water, snakes and animals, sharp debris, road collapse, hypothermia, and isolation of communities.

Drowning Management

Ensure rescuer safety, remove the patient from water only if safe, open airway, check breathing and pulse, start rescue breathing or CPR if needed, give oxygen, remove wet clothes, prevent hypothermia, immobilize spine if trauma suspected, and transport symptomatic patients.

Floodwater Safety

CDC emergency resources emphasize flood safety before, during, and after floods , . Key points: do not drive through floodwater, do not walk through moving water, avoid contact with electrical wires, assume floodwater is contaminated, wear gloves and boots, watch for open manholes, avoid unstable bridges and roads, and protect wounds from contaminated water.

Flood-Related Diseases

Disease/Condition	Cause/Risk	Important Clues
Acute diarrhea	Contaminated food/water	Loose stools, dehydration
Cholera-like illness	Unsafe water	Profuse watery diarrhea
Leptospirosis	Water contaminated with animal urine	Fever, calf pain, jaundice
Hepatitis A/E	Contaminated water	Fever, jaundice
Wound infection	Dirty water entering wounds	Redness, swelling, pus
Dengue/malaria risk	Mosquito breeding after stagnant water	Fever, body pain, chills
Snake bite	Displaced snakes	Fang marks, swelling, bleeding signs

Ambulance Operations During Floods

Stage ambulances on high ground, avoid flooded roads, coordinate with boat rescue teams, use alternate routes, protect equipment from water, carry PPE/blankets/oxygen/suction/trauma supplies/communication devices, notify hospitals before transport, use non-ambulance vehicles for green patients if appropriate and safe, and do not risk ambulance crew in fast water.

Exam pearls: Drowning is a major immediate cause of death in floods. Floodwater may contain sewage, chemicals, sharp objects, and animals. Electrocution risk is high around floodwater and fallen wires. Leptospirosis should be suspected after floodwater exposure with fever and calf pain. Ambulances should not enter unsafe floodwater.

Cyclones, Hurricanes, Storms, and Tornadoes

Cyclones, hurricanes, and typhoons are rotating storm systems with strong winds and heavy rain. CDC emergency resources include storm, hurricane, tornado, and severe weather safety guidance , .

Region	Common Term
Indian Ocean	Cyclone
Atlantic/Eastern Pacific	Hurricane
Western Pacific	Typhoon
Land-based rotating column	Tornado

Main hazards: high winds, flying debris, building collapse, flooding, storm surge, electrocution, falling trees, road blockage, and communication failure.

Health effects: blunt trauma, lacerations, fractures, head injury, drowning, hypothermia, electrocution, carbon monoxide poisoning from unsafe generator use, snake bite after flooding, and psychological trauma.

Ambulance Preparedness Before Cyclone/Storm

Fuel all vehicles, check oxygen/suction/defibrillator/batteries/radios, pre-position ambulances outside high-risk zones, identify safe routes and alternate routes, evacuate high-risk patients early, coordinate with hospitals, protect vehicles from flying debris and flooding, and keep crew food/water/PPE/lighting ready.

Exam pearls: Storm surge can be more dangerous than wind. Flying debris causes severe trauma. Generator use in enclosed spaces can cause carbon monoxide poisoning. Ambulances should be pre-positioned before roads are blocked. Hospitals may also be damaged and unable to receive patients.

Tsunami

A tsunami is a series of large sea waves usually triggered by undersea earthquakes, landslides, or volcanic activity. Warning signs include strong earthquake near coast, sudden sea withdrawal, loud ocean roar, unusual sea behavior, and official tsunami warning.

Health effects: drowning, near drowning, blunt trauma, penetrating trauma, fractures, aspiration, hypothermia, wound contamination, and psychological trauma.

Exam pearls: A tsunami is usually a series of waves, not a single wave. The first wave may not be the largest. Sea recession after an earthquake is a danger sign. Move inland and to higher ground immediately.

Heat Waves

A heat wave is a period of abnormally high temperature that can cause heat-related illness and excess deaths. CDC provides specific emergency preparedness resources related to extreme heat and disproportionately affected populations .

High-risk groups include elderly people, infants and children, pregnant women, outdoor workers, athletes, homeless people, people with heart or kidney disease, and those on diuretics, anticholinergics, antipsychotics, or beta-blockers.

Heat Illness Spectrum

Condition	Features	Severity
Heat rash	Itchy rash, sweating	Mild
Heat cramps	Painful muscle cramps	Mild/moderate
Heat syncope	Fainting in heat	Moderate
Heat exhaustion	Weakness, sweating, dizziness, nausea	Serious
Heat stroke	Altered mental status and severe hyperthermia	Life-threatening

Heat stroke is a life-threatening emergency with CNS dysfunction. Management: move to cool area, remove clothing, start rapid cooling immediately (cold-water immersion if possible, otherwise evaporative cooling + ice packs), manage ABCs, check glucose, treat seizure if present, and transport while continuing cooling.

Exam pearls: Altered mental status is the key danger sign. Do not delay cooling. Antipyretics such as paracetamol are not useful for heat stroke. Sweating may still be present in exertional heat stroke.

Lightning

Mechanisms of injury: direct strike, side flash, ground current, contact injury, and blast effect.

Clinical effects: cardiac arrest, respiratory arrest, burns, tympanic membrane rupture, confusion, seizures, paralysis, cataract (later), and trauma from fall or blast.

Reverse triage: Lightning incidents are unusual because apparently pulseless or apneic patients may survive with rapid ventilation and CPR. In multiple lightning victims, treat those without signs of life first if resources allow.

Exam pearls: Lightning victims do not carry electrical charge. It is safe to touch and resuscitate them. Respiratory arrest may continue after cardiac activity returns. Reverse triage is a classic exam point.

Wildfires

A wildfire is an uncontrolled fire in vegetation, forest, grassland, or wildland areas. CDC natural disaster resources include wildfire safety information .

Health effects: burns, smoke inhalation, carbon monoxide poisoning, asthma and COPD exacerbation, eye irritation, heat illness, trauma during evacuation, and psychological stress.

Suspect smoke inhalation if there are facial burns, singed nasal hair, soot in mouth or nose, hoarse voice, stridor, cough with black sputum, or altered mental status.

Carbon monoxide poisoning features: headache, dizziness, nausea, confusion, syncope, chest pain, and coma. Management: remove from exposure, give 100% oxygen, monitor ECG, and transport rapidly.

Exam pearls: Pulse oximetry may look falsely normal in carbon monoxide poisoning. Airway swelling after burns can progress rapidly. Early airway support may be lifesaving. Fire responders need respiratory and heat-stress protection.

Public Health Problems After Natural Disasters

Water and Sanitation

Common problems include contaminated drinking water, sewage overflow, lack of toilets, poor hand hygiene, open defecation, and poor waste disposal. Likely diseases include diarrhea, cholera-like illness, typhoid-like illness, hepatitis A/E, and skin infections.

Shelter Health

Overcrowding, poor ventilation, respiratory infections, poor sanitation, lack of privacy, violence risk, interrupted medications, and mental distress.

Vector Control

After floods and stagnant water, mosquito breeding may increase. Important actions include removing stagnant water, using mosquito nets, supporting local vector control, conducting fever surveillance, and providing health education.

Mental Health

Common reactions include fear, grief, insomnia, anxiety, depression, acute stress, PTSD symptoms, and survivor guilt. Psychological first aid includes ensuring safety, listening calmly, not forcing talking, connecting survivors with family, giving practical help, and referring severe cases.

Vulnerable Groups

CDC disaster epidemiology resources state that at-risk groups, also referred to as socially vulnerable populations, require special attention in a disaster . During disasters, populations with higher levels of social vulnerability are more likely to be adversely affected .

• Children: Risk of dehydration, hypothermia, fear, separation from family, and weight-based medication errors.
• Elderly: Limited mobility, chronic disease, medication interruption, heat and cold vulnerability, and falls.
• Pregnant women: Risk of preterm labor, bleeding, hypertension, dehydration, and lack of delivery care.
• Persons with disabilities: Evacuation barriers, communication barriers, loss of assistive devices, and difficulty accessing shelters.
• Chronic disease patients: Risk of missed dialysis, no insulin, no antihypertensives, oxygen supply interruption, and cardiac disease worsening.

Ambulance Disaster Preparedness Checklist

CDC's all-hazards preparedness guide emphasizes planning evacuation routes, practicing emergency plans, and knowing how local authorities will notify the public during emergencies .

Vehicle readiness: Fuel full, engine checked, tyres checked, spare tyre, lights and siren working, GPS/maps ready, battery charged, vehicle documents ready.

Medical equipment: Oxygen cylinders, bag-valve-mask, suction, defibrillator/AED, monitor, stretcher, spine board/scoop stretcher, cervical collars, splints, trauma dressings, tourniquets, IV fluids, emergency drugs according to protocol, burn dressings, and delivery kit.

Disaster supplies: Triage tags, PPE (helmets, gloves, boots, eye protection, masks/respirators), flashlights, batteries, blankets, rain gear, drinking water, food for crew, and communication device with charger/power bank.

Crew readiness: Disaster plan known, roles assigned, communication plan known, alternate routes known, family safety plan made, personal medicines carried, and hydration and rest planned.

Communication in Natural Disasters

METHANE Report

A structured major incident message:

• M — Major incident declared?
• E — Exact location
• T — Type of incident
• H — Hazards
• A — Access routes
• N — Number of casualties
• E — Emergency services required

ATMIST Patient Handover

• A — Age/name
• T — Time of incident
• M — Mechanism
• I — Injuries found
• S — Signs/vitals
• T — Treatment given