In-Flight Medical Emergency

See Also

Epidemiology (based on Peterson study)

Prevalence Inflight Emergencies: 24 to 130 emergencies per 1 Million passengers
1. One medical emergency for every 604 flights (11,920 emergencies in 7.2 Million flights)
2. Pre-Covid average levels of air travel at U.S. Airports (2018): 2.8 Million/day
Cabin crew manages 65-70% of inflight emergencies without health care professional assistance
Only 7% of medical emergencies required flight diversion
1. Only 25% of flight diversions required emergency department evaluation
2. Only 8% of flight diversions required hospital admission
3. Only 0.3% of flight diversions died
Most common in-flight emergencies
1. Syncope or Near Syncope (32-37%)
2. Respiratory symptoms (10-12%)
3. Nausea or Vomiting (10%)
References
1. Peterson (2013) N Engl J Med 368(22): 2073-33 [PubMed]
  1. http://www.nejm.org/doi/full/10.1056/NEJMoa1212052

Background

FAA requires cabin pressure <8000 feet (2438m)
1. Most airplane cabins are pressurized to 6500 feet (+/- 1000 feet)
2. 10% of airplane cabins are pressurized to 8000 feet
Oxygen Saturation on airplane drops by 3-4% or more
1. Atmospheric oxygen pressure may drop from 95 mmHg at sea level to 55 mmHg (90% O2Sat) at 8000 feet
2. May exacerbate patients already hypoxic (e.g. severe COPD)
3. Portable oxygen in flight is recommended if resting Oxygen Saturation <92% at sea level
Emergency landing secondary to medical emergency is expensive
1. Cost per incident: $500,000 to $1 Million dollars
2. Final decision to divert is per pilot discretion with input from ground medical control, dispatch, cabin crew
3. Only 4-7% of in-flight medical emergencies result in aircraft diversion
  1. Cardiac Arrest (57% of diversions and 86% of deaths, but only 0.2% of emergencies)
  2. Cardiac symptoms (18%)
  3. Obstetric emergency (18% of diversions, but only 0.7% of inflight emergencies)
  4. Suspected Cerebrovascular Accident (16%)
Medicolegal concerns for medical volunteers
1. Malpractice liability is based primarily on the laws of the airline's country of registry
2. Some documentation of in flight care may be required
3. Flight crew will ask that you verify credentials (i.e. medical license)
4. Medical providers should consider their own relative contraindications to participation
  1. Alcohol use
  2. Sedation (e.g. sleep aid use)
  3. Excessive Fatigue (sleep deprivation)
Good Samaritan
1. Aviation Medical Assistance Act (U.S., 1998) offers broad protection extending beyond Good Samaritan
2. Most other countries allow for Good Samaritan laws
3. Good Samaritan protections require that no payment or reimbursement is made
4. Good Samaritan protections assume that the flight crew asked for your medical assistance
Airlines ground medicine control
1. Ground-based Flight Medicine and emergency clinicians contracted by the airline
2. Will direct some process decisions (e.g. emergency landing indications)

Preparation
Airplane medical equipment

See FAA Mandated Emergency Medical Kit
Type of available medical supplies varies between airlines and countries
Oxygen supply may be limited
Available tools are limited (e.g. stethoscope, Automated External Defibrillators)
Noisy, tight environment of airplane limits evaluation (e.g. auscultation of Blood Pressure, cardiopulmonary exam)

Evaluation

Perform physical exam and obtain Vital Signs as able
Perform complete history, especially for high risk symptoms
1. Chest Pain
2. Shortness of Breath
3. Focal neurologic deficit

Management

Syncope or Near Syncope
1. Place patient supine (e.g. floor of aisle or galley) with legs elevated
2. Apply Supplemental Oxygen
3. Check Blood Glucose
4. Encourage oral hydration if able (and consider intravenous hydration if not and hypotensive)
5. Contact ground control and consider flight diversion if not recovering within 15-30 minutes
Dyspnea
1. See Cabin pressure and low atmospheric oxygen as above
2. Apply Supplemental Oxygen
3. Consider Bronchodilator (e.g. Albuterol) for Asthma and COPD exacerbations
4. Consider causes (e.g. Pneumothorax, Pulmonary Embolism, CHF, Pneumonia, toxin exposure)
5. Oxygen requirements >4 L/min may not be sustained by oxygen supply (consider flight diversion)
Chest Pain
1. Consider Aspirin 324 mg and Sublingual Nitroglycerin 0.4 mg if Acute Coronary Syndrome is suspected
  1. Exercise caution in Hypotension
2. Consider Supplemental Oxygen
3. Consider Chest Pain Causes based on history and exam
4. Consider flight diversion for refractory Chest Pain with associated cardiopulmonary findings or hemodynamic instability
Cardiac Arrest
1. Follow ACLS protocol with high quality CPR, AED, and ACLS medications as indicated
2. Continue CPR (rotating rescuers every 2 minutes) until endpoint
  1. Unsafe or unable to continue
  2. Resuscitation continued by ground Paramedics on landing
  3. CPR for 30 minutes, no signs of life and no shock advised by AED
Cerebrovascular Accident
1. Evaluate for timing of onset and significant neurologic deficits (esp. <3 hours and NIH Stroke Scale 5 or greater)
2. Evaluate for signs and symptoms of Intracranial Hemorrhage (e.g. Thunderclap Headache, Anticoagulation)
3. Consider alternative diagnoses (e.g. Migraine Headache)
4. Apply Supplemental Oxygen
5. Avoid Aspirin
6. Consult with ground medical control and consider flight diversion
Seizure
1. Higher risk in-flight due to altitude related Hypoxemia and sleep deprivation
2. ABC Management
3. Give Benzodiazepine if available (e.g. rectal Diazepam)
4. Give additional dose of patient's own Seizure medication if available and patient able to take
5. Consider flight diversion for Status Epilepticus or persistent postictal state
Obstetric Emergency - General
1. History includes Gestational age, Multiple Gestation, pregnancy complications, Abdominal Pain and Vaginal Bleeding
2. Consider Placental Abruption, active labor, Preterm Labor, Preeclampsia
3. Diversion not typically needed if Vaginal Bleeding <1 pad/hour, Gestational age <20 weeks, hemodynamically stable
4. Diversion recommended for Gestational age >20 weeks and severe Vaginal Bleeding or Abdominal Pain
Obstetric Emergency - Inflight Vaginal Delivery
1. See Spontaneous Vaginal Delivery
2. See Newborn Resuscitation
3. Delivery Kit (including clamp, scissors, Oxytocin) may be available on plane
4. Warm the baby with airline blankets
5. Clamp the cord (or tie with shoe lace or similar) and cut
6. Uterine massage until Uterus is firm (bimanual massage may be needed) and give Oxytocin if available
7. Monitor mother for Vaginal Bleeding with large menstrual pads
  1. Each soaked pad contains 250 ml blood (2 pads = 500 ml, Postpartum Hemorrhage)
8. Monitor the baby and mother with Vital Signs every 30 minutes
9. Khatib and Cardy in Swadron (2022) EM:Rap 22(8): 6-7
Psychiatric Emergency (e.g. Anxiety, Agitation, Psychosis)
1. See Calming the Agitated Patient
2. Consider Alcohol Intoxication, drug Intoxication or withdrawal, Panic Attack, Posttraumatic Stress Disorder
3. Flight crew will institute security protocols if patient cannot be verbally de-escalated
Anaphylaxis
1. Start with Epinephrine and Diphenhydramine
Traumatic Injury
1. Control bleeding (e.g. direct pressure)
2. Control Epistaxis (e.g. pressure below bridge of nose)
3. Splint suspected Fractures and evaluate for impaired distal neurovascular supply
4. Some dislocations may be amenable to non-sedated reduction (e.g. davos maneuver for Shoulder Dislocation)

Prevention

See Air Travel Restriction
Do not remove drainage tubes immediately prior to air travel (risk of significantly increased pressure)

References

Lin and Delaney in Herbert (2015) EM:Rap 15(5): 7-8
Leibman and Orman in Herbert (2014) EM:Rap 14(9): 8
Hu (2021) Am Fam Physician 103(9): 547-52 [PubMed]