Data-Driven Estimation of the Impact of Diversions Due to In-Flight Medical Emergencies on Flight Delay and Aircraft Operating Costs.

INTRODUCTION: In-flight medical emergencies (IFMEs) average 1 of every 604 flights and are expected to increase as the population ages and air travel increases. Flight diversions, or the rerouting of a flight to an alternate destination, occur in 2 to 13% of IFME cases, but may or may not be necessary as determined after the fact. Estimating the effect of IFME diversions compared to nonmedical diversions can be expected to improve our understanding of their impact and allow for more appropriate decision making during IFMEs.METHODS: The current study matched multiple disparate datasets, including medical data, flight plan and track data, passenger statistics, and financial data. Chi-squared analysis and independent samples t-tests compared diversion delays and costs metrics between flights diverted for medical vs. nonmedical reasons. Data were restricted to domestic flights between 1/1/2018 and 6/30/2019.RESULTS: Over 70% of diverted flights recover (continue on to their intended destination after diverting); however, flights diverted due to IFMEs recover more often and more quickly than do flights diverted for nonmedical reasons. IFME diversions introduce less delay overall and cost less in terms of direct operating costs and passenger value of time (averaging around 38,000) than do flights diverted for nonmedical reasons.DISCUSSION: Flights diverted due to IFMEs appear to have less impact overall than do flights diverted for nonmedical reasons. However, the lack of information related to costs for nonrecovered flights and the decision factors involved during nonmedical diversions hinders our ability to offer further insights.Lewis BA, Gawron VJ, Esmaeilzadeh E, Mayer RH, Moreno-Hines F, Nerwich N, Alves PM. Data-driven estimation of the impact of diversions due to in-flight medical emergencies on flight delay and aircraft operating costs. Aerosp Med Hum Perform. 2021; 92(2):99105.

Characterization of In-Flight Medical Events Involving Children on Commercial Airline Flights.

STUDY OBJECTIVE: More than 4 billion passengers travel on commercial airline flights yearly. Although in-flight medical events involving adult passengers have been well characterized, data describing those affecting children are lacking. This study seeks to characterize pediatric in-flight medical events and their immediate outcomes, using a worldwide sample. METHODS: We reviewed the records of all in-flight medical events from January 1, 2015, to October 31, 2016, involving children younger than 19 years treated in consultation with a ground-based medical support center providing medical support to 77 commercial airlines worldwide. We characterized these in-flight medical events and determined factors associated with the need for additional care at destination or aircraft diversion. RESULTS: From a total of 75,587 in-flight medical events, we identified 11,719 (15.5%) involving children. Most in-flight medical events occurred on long-haul flights (76.1%), and 14% involved lap infants. In-flight care was generally provided by crew members only (88.6%), and physician (8.7%) or nurse (2.1%) passenger volunteers. Most in-flight medical events were resolved in flight (82.9%), whereas 16.5% required additional care on landing, and 0.5% led to aircraft diversion. The most common diagnostic categories were nausea or vomiting (33.9%), fever or chills (22.2%), and acute allergic reaction (5.5%). Events involving lap infants, syncope, seizures, burns, dyspnea, blunt trauma, lacerations, or congenital heart disease; those requiring the assistance of a volunteer medical provider; or those requiring the use of oxygen were positively correlated with the need for additional care after disembarkment. CONCLUSION: Most pediatric in-flight medical events are resolved in flight, and very few lead to aircraft diversion, yet 1 in 6 cases requires additional care.

Quality of Electrocardiograms Obtained in Flight by Airline Flight Attendants.

BACKGROUND: Handling cases of chest pain aboard commercial flights is challenging for crewmembers, onboard medical volunteers, and ground-based doctors providing remote advice. Obtaining an electrocardiogram (ECG) in-flight could help in dictating the management of such cases. The ability to diagnose or rule out ST-segment elevation myocardial infarction (STEMI) would have clinical and prognostic implications. The feasibility of obtaining good quality ECG tracings by flight attendants in flight is not known.METHODS: A series of 200 consecutive ECG tracings transmitted to a ground-based medical support provider were independently reviewed by four observers who ranked the ECG tracings according to a quality score (QS) criteria, as well as trying to identify or rule-out cases of STEMI.RESULTS: ECG quality was considered good enough to extract useful information in 170 of 200 tracings (85%). Seven cases of STEMI were identified. A STEMI was confidently ruled out in 104 cases. Additional abnormalities of variable clinical importance were also detected.DISCUSSION: ECGs are essential in the prehospital management of chest pain cases. ECGs obtained in flight by airline flight attendants were mostly of diagnostic quality, allowing confirmation or ruling out of STEMI, as well as detecting arrhythmias of clinical significance in case management.Alves PM, Lindgren JA, Streitwieser DR, Anzola E, Ahmed N, Nerwich N. Quality of electrocardiograms obtained in flight by airline flight attendents. Aerosp Med Hum Perform. 2019; 90(4):405-408.

In-Flight Injuries Involving Children on Commercial Airline Flights.

BACKGROUND: More than 3 billion passengers are transported every year on commercial airline flights worldwide, many of whom are children. The incidence of in-flight medical events (IFMEs) affecting children is largely unknown. This study seeks to characterize pediatric IFMEs, with particular focus on in-flight injuries (IFIs). METHODS: We reviewed the records of all IFMEs from January 2009 to January 2014 involving children treated in consultation with a ground-based medical support center providing medical support to commercial airlines. RESULTS: Among 114 222 IFMEs, we identified 12 226 (10.7%) cases involving children. In-flight medical events commonly involved gastrointestinal (35.4%), infectious (20.3%), neurological (12.2%), allergic (8.6%), and respiratory (6.3%) conditions. In addition, 400 cases (3.3%) of IFMEs involved IFIs. Subjects who sustained IFIs were younger than those involved in other medical events (3 [1-8] vs 7 [3-14] y, respectively), and lap infants were overrepresented (35.8% of IFIs vs 15.9% of other medical events). Examples of IFIs included burns, contusions, and lacerations from falls in unrestrained lap infants; fallen objects from the overhead bin; and trauma to extremities by the service cart or aisle traffic. CONCLUSIONS: Pediatric IFIs are relatively infrequent given the total passenger traffic but are not negligible. Unrestrained lap children are prone to IFIs, particularly during meal service or turbulence, but not only then. Children occupying aisle seats are vulnerable to injury from fallen objects, aisle traffic, and burns from mishandled hot items. The possible protection from using in-flight child restraints might extend beyond takeoff and landing operations or during turbulence.

Medical Guidelines for Airline Travel: Management of In-Flight Cardiac Arrest.

INTRODUCTION: Although cardiac arrest during airline flights is relatively uncommon, the unusual setting, limited resources, and the variability of the skills in medical volunteers present unique challenges. Survival in patients who suffer a witnessed arrest with a shockable rhythm who are treated promptly has improved since the advent of widely available automated external defibrillators (AEDs). In general, the chances of survival from an out-of-hospital cardiac arrest (OHCA) are greater when ventricular fibrillation (VF) is seen as the initial rhythm or if there is return of spontaneous circulation (ROSC). Not all in-flight cardiac arrests are witnessed because cabin crew or fellow passengers might simply assume that the victim is sleeping. Based upon a review of the literature on resuscitation after OHCA, we recommend that automatic external defibrillators be carried on all commercial airline flights, regardless of duration. Patients presenting with shockable rhythm (e.g., VF, unstable ventricular tachycardia) have the best prognosis for survival and usually require diversion of the aircraft for advanced cardiac life support (ACLS). Because diversion may require interruption of cardiopulmonary resuscitation (CPR) and may impact flight safety, the volunteer rescuer, cabin crew, flight crew, and medical consultation services should discuss the possible outcome and operational considerations before recommending a diversion for a patient with a nonshockable rhythm. The recommendations in this article were developed by members of the Air Transport Medicine and Aerospace Human Performance Committees and approved by the Council of the Aerospace Medical Association.Ruskin KJ, Ricaurte EM, Alves PM. Medical guidelines for airline travel: management of in-flight cardiac arrest. Aerosp Med Hum Perform. 2018; 89(8):754-759.

In-Flight Management of a Supraventricular Tachycardia Using Telemedicine.

BACKGROUND: Supraventricular tachycardia (SVT) is a common presenting arrhythmia in the general population. Cases of SVT presenting during commercial air travel are always challenging as they might be confused with other conditions requiring different treatment strategies. We present a case of an in-flight SVT that was successfully managed using telemedicine support. CASE REPORT: A 33-yr-old woman developed chest pain and dizziness while on an international commercial flight. Vital signs obtained on an on-board telemedicine device recorded an initial heart rate and blood pressure of 220 bpm and 128/78 mmHg, respectively. An electrocardiogram (ECG) was also obtained and transmitted to the ground-based medical support (GBMS) center where an SVT was diagnosed. Vagal maneuvers were recommended which resulted in a return to sinus rhythm and stabilization of the patient. DISCUSSION: In parallel to the global increase in commercial air travel, it is expected that the incidence of in-flight arrhythmias will also increase, including SVTs. Vagal maneuvers are a safe, first-line option. While treating patients with a symptomatic tachyarrhythmia it is essential to diagnose the underlying arrhythmia, especially when initial maneuvers fail. Telemedicine, with transmission of vital signs and ECGs to GBMS centers, can enable diagnosis and guide management of in-flight SVTs, distinguishing them from other forms of cardiac arrhythmia. Undifferentiated chest pain and dizziness are common causes for flight diversions and, as such, could potentially be prevented in some instances by using telemedicine.Voerman JJ, Hoffe ME, Surka S, Alves PM. In-flight management of a supraventricular tachycardia using telemedicine. Aerosp Med Hum Perform. 2018; 89(7):657-660.

Cross-Sectional Survey of Physicians on Providing Volunteer Care for In-Flight Medical Events.

BACKGROUND: Airline carriers have equipment, procedures, and protocols in place to handle in-flight medical events (IFMEs). Community physicians may be asked for aid during IFMEs. Cross-Sectional Survey of Physicians on Providing Volunteer Care for In-Flight Medical Events surveyed self-assessed awareness and knowledge, perceived barriers, and suggestions for improving responses to IFMEs. METHODS: We composed a survey regarding clinicians' self-assessed understanding of in-flight resources, procedures, flight environmental issues, and Good Samaritan protections. The survey was distributed primarily via electronic mail to medical staff list serves to a total of approximately 1300 physicians representing 2 health networks that serve urban, suburban, and rural areas in both inpatient and outpatient settings. RESULTS: Total number of responses was 418. Physician response rate was 29.2% (379/1300). In 3% (39/1300), the responder either failed to indicate their background or was another type of health care professional (e.g., dentist, medical student, physician assistant). Of the physicians, 37.5% (142/379) were primary care and 42% (177/418) of responders reported at least one experience of being asked to volunteer. When asked how well they understand the protocols with which medical events are handled, 64% (262/412) responded "not at all" and 23% (94/412) reported "a little" knowledge. Only 56% (223/397) answered that 75% or more of U.S. flights have ground medical support available. There were 73% (298/411) who believed airlines were required to have medical supplies, but 54% (222/410) reported no knowledge of supplies available. A total of 69% (279/403) believed or were sure that the U.S. has a Good Samaritan law that applies to IFMEs. DISCUSSION: Many physicians lack basic knowledge about IFMEs. Responders may assist more effectively if better informed about protocols and the availability of ground medical support. Education and timely information support are recommended.Chatfield E, Bond WF, McCay B, Thibeault C, Alves PM, Squillante M, Timpe J, Cook CJ, Bertino RE. Cross-Sectional Survey of Physicians on Providing Volunteer Care for In-Flight Medical Events. Aerosp Med Hum Perform. 2017; 88(9):876-879.

Prognostic Factors for Outcomes of In-Flight Sudden Cardiac Arrest on Commercial Airlines.

BACKGROUND: In-flight cardiac arrest (IFCA) is a relatively rare but challenging event. Outcomes and prognostic factors are not entirely understood for victims of IFCAs in commercial aviation. METHODS: This was a retrospective cohort study of airline passengers who experienced IFCA. Demographic and operational variables were studied to identify association in a multivariate logistic regression model with the outcome of survival-to-hospital. In-flight medical emergencies were processed by a ground-based medical center. Subsequent comparisons were made between reported shockable-rhythm (RSR) and reported non-shockable-rhythm (RNSR) groups. Logistic regression was also used to identify predictors for shock advised and flight diversions using a case control study design. Significant predictors for survival-to-hospital were RSR and remaining flight time to destination. RESULTS: The percentage of RSR cases was 24.6%. The survival to hospital admission was 22.7% (22/97) for passengers in RSR compared with 2.4% (7/297) in the RNSR group. The adjusted odds ratio for survival-to-hospital for the RSR group compared to the RNSR group was 13.6 (5.5-33.5). The model showed odds for survival to hospital decreased with longer scheduled remaining flight duration with adjusted OR = 0.701 (0.535-0.920) per hour increase. No correlation between diversions and survival for RSR cases was found. CONCLUSIONS: Survival-to-hospital from IFCAs is best when an RSR is present. The percentage of RSR cases was lower than in other out-of-hospital cardiac arrest (OHCA) settings, which suggests delayed discovery. Flight diversions did not significantly affect resuscitation outcome. We emphasize good quality cardio-pulmonary resuscitation (CPR) and early defibrillation as key factors for IFCA survival. Alves PM, DeJohn CA, Ricaurte EM, Mills WD. Prognostic factors for outcomes of in-flight sudden cardiac arrest on commercial airlines. Aerosp Med Hum Perform. 2016; 87(10):862-868.

AsMA Medical Guidelines for Air Travel: In-Flight Medical Care.

INTRODUCTION: Medical Guidelines for Airline Travel provide information that enables healthcare providers to properly advise patients who plan to travel by air. All airlines are required to provide first aid training for cabin crew, and the crew are responsible for managing any in-flight medical events. There are also regulatory requirements for the carriage of first aid and medical kits. AsMA has developed recommendations for first aid kits, emergency medical kits, and universal precaution kits.

Fatalities above 30,000 feet: characterizing pediatric deaths on commercial airline flights worldwide.

OBJECTIVES: We conducted this study to characterize in-flight pediatric fatalities onboard commercial airline flights worldwide and identify patterns that would have been unnoticed through single case analysis of these relative rare events. DESIGN: Retrospective cohort study of pediatric in-flight medical emergencies resulting in fatalities between January 2010 and June 2013. SETTING: A ground-based medical support center providing remote medical support to commercial airlines worldwide. PATIENTS: Children (age 0-18 yr) who experienced a medical emergency resulting in death during a commercial airline flight. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: There were a total of 7,573 in-flight medical emergencies involving children reported to the ground-based medical support center, resulting in 10 deaths (0.13% of all pediatric in-flight emergencies). The median subject age was 3.5 months with 90% being younger than 2 years, the age until which children are allowed to travel sharing a seat with an adult passenger, also known as lap infants. Six patients had no previous medical history, with one suffering cardiorespiratory arrest after developing acute respiratory distress during flight and five found asystolic (including four lap infants). Four subjects had preflight medical conditions, including two children traveling for the purpose of accessing advanced medical care. CONCLUSIONS: Pediatric in-flight fatalities are rare, but death occurs most commonly in infants and in subjects with a preexisting medical condition. The number of fatalities involving seemingly previously healthy children under the age of 2 years (lap infants) is intriguing and could indicate a vulnerable population at increased risk of death related to in-flight environmental factors, sleeping arrangements, or yet another unrecognized factor.

Cardiovascular events on board commercial maritime vessels: a two-year review.

BACKGROUND: Cardiovascular diseases (CVDs) are an important concern in merchant maritime operations. They are responsible for the majority of deaths at sea that are not related to injury or violence. The objective was to better understand the epidemiology of CVD in merchant maritime operations. MATERIAL AND METHODS: Retrospective review of medical events on board merchant maritime vessels over a period of two years, from a US-based telemedicine provider's database. RESULTS: A total of 1,394 cases were initially retrieved from the database. CVD was diagnosed in 29 cases and was the eleventh leading cause for accessing the telemedicine provider. Five deaths occurred in the study period, three of which related to CVDs. CVDs resulted in more diversions and the utilization of more urgent means of communication. DISCUSSION: CVDs present a challenge in maritime health. The current pre-employment system is not, in a reasonable cost/benefit balance, able to prevent on board events from occurring. The success of telemedicine depends heavily on the onsite resources, both human and material. Automated External Defibrillators (AEDs), along with other devices such as multi-parameter monitors, are tools generally available to address acute presentations of CVDs, but their applicability on board commercial ships is a matter of controversy. CONCLUSIONS: CVDs are an important concern in commercial maritime operations due to the need for subsequent evaluation and potential complications including the risk of sudden cardiac arrest. In this study, CVDs were probably responsible for three on board deaths. Additional research is warranted to provide more evidence about the best resources to have on board to handle CVDs more effectively.

Impact of influenza vaccination on civilian aircrew illness and absenteeism.

BACKGROUND: Approximately 10% of the general population worldwide acquires influenza infection every year. Airline crews run a particularly high risk of contracting influenza and influenza-like viruses because they come in contact with hundreds of potentially infected individuals every day. Respiratory diseases are the most frequent cause of absenteeism among flight crews in airline companies. Several studies have shown the efficacy of influenza vaccination in the workplace of healthy, working adults leading to increased productivity and lower absenteeism. We conducted a double blind, randomized, placebo-controlled study on flight crews of an airline company in order to determine the safety and efficacy of a trivalent inactivated influenza vaccine in reducing illness and absences from work. METHODS: The 813 healthy members of a Brazilian airline company were randomly assigned to receive injections of either an influenza vaccine or a placebo, with a follow-up period of 7 mo after vaccination. Primary outcomes included influenza-like illness episodes and absenteeism from work due to such episodes. RESULTS: Demographic characteristics were similar in the two groups. No significant side-effects occurred in either group. Compared to the placebo group, individuals receiving the vaccine showed 39.5% fewer episodes of flu-like illness (p < 0.001) and 26% fewer days of work lost (p = 0.03). The vaccinated group developed 33% fewer episodes of any severe flu-like illness (p < 0.01). CONCLUSION: The data indicates that influenza vaccination is safe in airline flight crews and may produce health-related benefits including reduced absenteeism.