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WELCOME. Programme. “When they take care of you like that, you don’t mind fighting” - Wounded Army soldier on his evacuation by air. Air Evacuation of Casualties. Sqn Ldr AVK Raju Chief Medical Officer Indian Aviation Contingent – II MONUC avkraju123@gmail.com. Plan.
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“When they take care of you like that, you don’t mind fighting” - Wounded Army soldier on his evacuation by air
Air Evacuation of Casualties SqnLdr AVK Raju Chief Medical Officer Indian Aviation Contingent – II MONUC avkraju123@gmail.com
Plan • History and evolution of air evacuation • Aim • Aeromedical issues • System specific clinical conditions • Practical problems • Handy tips • Prioritisation • Pre flight – In flight – Post flight considerations
History of air evacuation… • 1870: Aeromedical evacuation idea conceived • 1910: Siege of Paris: 160 soldiers evacuated in hot air balloon • 1928: Nicaragua, first US military airlift • 1929: Established air evacuation officially • 1937: International Aeromedical Association- 62 nations • 1936-39: Germans air evacuated soldiers • 1941: USAF in WW II • 1946: Helicopters used for medical air-evacuation
Death rate of wounded • World War I – 8.5% • World War II – 4% • Korean War – 2% • Vietnam War – 1% [ Aeromedical evacuation/Antibiotics/Advances in Medical Science]
Air Evacuation Revolutionised mode of evacuation • Helicopters • Quick access to trauma sites • Land where there are no air strips • Fixed wing aircrafts • Spacious • Comfortable • Pressurised
Aim • Overcome adverse terrain • Enable early institution of definitive treatment • Avoidance of infection • Save skilled man power • Keep morale of personnel high • Keeps communication lines free • Economy • Safety • Comfort
Circumstances of Casualty Evacuation • Life saving measures • Forward areas to hospitals • In between hospitals • Errands of mercy
Disadvantage of Aero-medical evacuation… …lack of controlled environment
Aeromedical Issues in Cas evac • Hypoxia • Expansion of gases • Acceleration • Vibration • Noise • Humidity • Physical requirements – space, toilets etc
Hypoxia • Dalton’s Law of Partial Pressures • “Hypoxia at altitude” • All patients must be on supplemental Oxygen regardless of their clinical condition • CVS cases/Ischaemic cases – special precautions
Expansion of gases • Boyle’s Law • Expansion of gases trapped within the body • Special precautions – Pneumothorax, Penetrating head or eye injury, Bowel obstruction, Ruptured Tympanic Membrane
Cardiovascular Diseases • Supplemental Oxygen – “Must” • Lack of Oxygen – Cardiac catastrophe/Arrythmia • AMI – ideally no air evacuation for 06 weeks (?) • CPR board
Respiratory System • Supplemental Oxygen • Obstructive Pulmonary Disease – thorough evaluation • Untreated Pneumothorax – air evacuation contraindicated in presence of respiratory embarrassment • Pulmonary Surgery – air evacuation after proper convalescence • Pneumonia – Supplemental Oxygen !
Blood Disorders • Haemoglobin - < 7 gm% • Heamoglobin - < 8.5 gm% ‘or’ Sickle Cell Anaemia
Neurological Conditions • Increased intracranial pressure – supplemental Oxygen • Head Injury – Position of Head at towards the rear Acceleration
Neurological Conditions • CSF Leak through nose/ear – air evacuation contraindicated [Suction of air/bacteria during descent of aircraft] • Seizures – Hypoxia can trigger seizures
Orthopaedic cases • Sufficient time should have elapsed before air evacuation • Pressure changes – soft tissue oedema - ? Vascular compromise • Air splint – avoided ! • Traction equipment – possible missiles !
Burns • Pulmonary burns to be ascertained before air transportation • Air evacuation of patient with pulmonary burns – fatal • Pre flight Chest X-ray – mandatory • Stabilisation of patient – patency of airway, adequate ventilation, Oxygenation and fluid resuscitation
Gastro Intestinal Cases • Recent Adbominal Surgery cases – extra care • Gas in abdomen – expansion - ? Pain/Bowel circulation compromise/ ? rupture of sutures
Neuro Psychiatry Cases • Adequate observation prior to air transportation • Kept adequately sedated • Availability of restraint system
Pregnancy • Active labour – only contraindication • High risk obstetric cases – safe • Placental insufficiency – supplemental Oxygen • Altitude restriction – 5000’ (abdominal gas distension)
Prior to any air evacuation…. Ponder over the following questions: • Is the risk to the patient being transferred less than the risk of not being moved? • Is the patient adequately stabilised? • Do the benefits of the move justify the clinical and fiscal costs? • Is the move medically necessary or driven by emotion or family based concern? • Is the move based on necessity or convenience?
Practical problems ! • BP monitoring/checking of pulse difficult • Auscultation is difficult • Difficult to establish IV line • Difficult to pass Naso Gastric tube, catheterise • Nearly impossible to Intubate • CPR is difficult • Motion Sickness – vertigo/vomiting - ? Airway compromise • Electro Medical equipment – may interfere with the flight instruments
Handy tips... • Electronic BP and HR monitor • 2 x wide bore IV canulas in place, syringes filled with drugs • If needed, Intubate with ET tube before the sortie • NG tube, catheterisation pre flight procedure • All catheters to be filled with Normal Saline • For Air Sickness: Tab of Cinnarizine – 30 min before air evacuation sortie & low flow Oxygen • Tab Pseudoephidrine/Vasoconstrictor Nasal Drops – prevents OtiticBarotrauma • CPR board • Humidified Oxygen
Relative contraindications • Infectious diseases • Moribund patient • Offensive patient • Decompression sickness
Priorities of evacuation Priority 1. Patient whose transfer by quickest means is necessary as a life saving measureor to avoid serious permanent disability Priority 2. Patient whose condition is likely to be adversely affected unless they are speedily evacuated or who need early specialized treatment Priority 3. Patients whose immediate treatment are with in the powers of local medical units, but whose progress would benefit from movement by air rather than by surface transport Priority 4. Patients for whom movement by air is a matter of convenience rather than a medical requirement
Preflight Procedures ‘Understand the case well’ Briefing of pilot & crew 1. Height limitations required 2. Intermediate stops 3. Precaution in transfer of special cases 4.The aircraft for use for Evacuation should be fitted with proper equipment. 5. Communication facilities with departure intermediate & destination air field 6. Captain of aircraft in charge of over all discipline
Inflight • Fluid management • Oxygen/ IV line management • Medicines intake • Brief cabin/ aircrew for any changes from planned • Prevent exacerbation deterioration in clinical condition • Manage emergencies
Post flight • Make a note of problems encountered • Brief the Hospital who are receiving the patient • Brief the Hospital who have demanded air evacuation • Share your experiences and suggestions on ‘Lotus’
IV Fluids Resuscitation equipment including Oxygen Apparatus Doctor’s Bag Oxygen Mask Physiological Monitor & Defibrillator Spinal Board Ortho Scoop stretcher + splints Stretcher Suction Apparatus Urine/Vomitus/Stool Receptacles can be kept under the seats
Loading of patient from the rear Patient being monitored and being rendered medical treatment
To summarise…. Special precautions I. Condition susceptible to pressure change 1. CNS Air in CNS due to surgery or trauma, CSF Rhinorrhoea 2. Eye- Perforating Injury 3. Ear ASOM/ Mastoiditis/ Eustachian tube stenosis, Sinusitis 4. Respiratory System Pneumothorax/ Mediastinal Emphysema/ Sucking Wounds/ Open case of TB
5. GIT Hernias/ Gangrenous Appendicitis/ Penetrating Perforating Wounds/ Post Operative Cases/ Colostomies/ Liver Abscess 6. Skin Gas Gangrene/ Subcutaneous Emphysema 7. Maxillofacial injuries Till wires are removed 8. Decompression sickness
Cases requiring special attention II.Condition susceptible to hypoxia 1. CNS Head injury & epilepsy 2. Eye Ocular injuries/ Post Surgical Cases/ Glaucomatous Eye 3. RS Reduced vital capacity/ Pulmonary HT/Pul surgery 4. CVS Angina/ MI/ HT/ CCF/ Cardiac arrhythmia Require supplemental oxygen 5. Blood Anemia less than 7 gm%
Remember...... Murphy’s Law: “If anything has to go wrong, it will go wrong” “If you are prepared for the worst.. the worst seldom happens; If not prepared…. the worst is guaranteed to happen”