Efficacy of pseudoephedrine for the prevention of barotrauma during air travel

[The professional ear user-implications for the prevention, diagnosis, and treatment of ear diseases]

BACKGROUND

Perfect hearing is crucial to the practice of various professions, such as instrument makers, musicians, sound engineers, and other professions not related to music, such as sonar technicians. For people of these occupational groups, we propose the term "professional ear user" (PEU) in analogy to "professional voice user". PEUs have special requirements for their hearing health, as they have well-known above-average auditory perceptual abilities on which they are professionally dependent.

OBJECTIVE

The purpose of this narrative review is to summarize selected aspects of the prevention, diagnosis, and treatment of ear disorders in PEUs.

RESULTS AND CONCLUSION

Prevention of hearing disorders and other ear diseases includes protection from excessive sound levels, avoidance of ototoxins and nicotine, and a safe manner of cleaning the outer auditory canal. Diagnosing hearing disorders in PEUs can be challenging, since subclinical but relevant changes in hearing cannot be reliably objectified by conventional audiometric methods. Moreover, the fact that a PEU is affected by an ear disease may influence treatment decisions. Further, physicians must be vigilant for non-organic ear diseases in PEUs. Lastly, measures to promote comprehensive ear health in PEUs as part of an educational program and to maintain ear health by means of a specialized otolaryngology service are discussed. In contrast to existing concepts, we lay the attention on the entirety of occupational groups that are specifically dependent on their ear health in a professional setting. In this context, we suggest avoiding a sole focus on hearing disorders and their prevention, but rather encourage the maintenance of a comprehensive ear health.

Eustachian Tube Function in Flight Attendants

Eustachian tube (ET) function is of utmost importance in people who are under constant barometric pressure changes in their daily lives. Proper functioning is essential in avoiding pressure related injuries. We aimed to investigate how well the ET functions in flying personnel and how it compares to the non-flying population.Prospective study. Acibadem University Atakent Hospital. 115 participants were included in the study. Each underwent a thorough otorhinolarynglogic examination then undertook a tympanogram followed by eustachian tube function (EtFT) test. A statistically significant difference in ear volume was observed in flight personnel. EtFT results showed the ability to equalize pressure after Valsalva manouvre was also significantly higher in flight personnel. Flight attendants that are subject to pressure changes throughout their careers do seem to be more capable of equalizing pressure through manoeuvres such as the Valsalva. This may be due to the fact that continuous pressure changes creates a more pliable tympanic membrane.

Orbital Fractures and Air Travel

Previous surveys indicate that the majority of clinicians recommend avoidance of air travel for a period of time following an acute orbital fracture. This advice has largely been based on the theoretical risk that in-flight pressure variation may exacerbate orbital emphysema and produce visual compromise, though no previous reviews have been conducted on the evidence underpinning this advice. The purpose of this study was, therefore, to conduct a systematic review of the literature pertaining to the safety of air travel in the setting of an acute orbital fracture. A systematic review of the OVID Medline database - and of cases referenced as providing evidence for adverse outcomes due to flying with an orbital fracture - was carried out.Two articles were identified from the literature with data specific to patients who undertook air travel following orbital fractures. A large case series identified no complications in patients exposed to both pressurized and unpressurized air travel, and only a single case report detailed an adverse outcome requiring intervention. The remainder of the articles that had previously been cited as evidence against air travel involved additional factors such as intra-ocular pathologies. There is, therefore, a paucity of evidence to support the conventional advice regarding avoidance of air travel, though clinicians should exclude the possibility of an associated intra-ocular injury, advise against nose-blowing in flight, and provide advice regarding alternative methods to the Valsalva maneuver for equalizing middle ear pressure in flight.

LEVEL OF EVIDENCE

IV.

Prevention of Otic Barotrauma in Aviation: A Systematic Review

OBJECTIVE

To conduct a systematic review of the published evidence relating to the prevention of otic barotrauma in aviation. In particular, this review sought to identify procedures, techniques, devices, and medications for the prevention of otic barotrauma as well as evaluate the evidence relating to their efficacy.

DATA SOURCES

Ten databases including Embase, MEDLINE, the Cochrane Database of Systematic Reviews, and the Cochrane Central Register of Controlled Trials were searched using the full historical range.

STUDY SELECTION

English language articles including more than or equal to five participants or cases were included. Outcomes of interest were reduced severity or the successful prevention of otic barotrauma in participants undergoing gradual changes in pressure during air travel or its simulation.

DATA EXTRACTION

Articles and data were extracted and analyzed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses and other international guidelines.

CONCLUSIONS

This review highlights the lack of published evidence relating to what is a significant and increasingly common problem in otology. There is level 1 evidence that supports the efficacy of oral pseudoephedrine (120 mg) in preventing otic barotrauma in adults. However, oral pseudoephedrine (1 mg/kg) does not appear to be effective in children. There is insufficient evidence to support the efficacy of either nasal balloon inflation or pressure-equalizing ear plugs for the prevention of otic barotrauma. A recently reported, novel technique for insertion of temporary tympanostomy tubes is promising but requires further evaluation.

Barosinusitis: Comprehensive review and proposed new classification system

Background:

Barosinusitis, or sinus barotrauma, may arise from changes in ambient pressure that are not compensated by force equalization mechanisms within the paranasal sinuses. Barosinusitis is most commonly seen with barometric changes during flight or diving. Understanding and better classifying the pathophysiology, clinical presentation, and management of barosinusitis are essential to improve patient care.

Objectives:

To perform a comprehensive review of the available literature regarding sinus barotrauma.

Methods:

A comprehensive literature search that used the terms “barosinusitis,” “sinus barotrauma,” and “aerosinusitis” was conducted, and all identified titles were reviewed for relevance to the upper airway and paranasal sinuses. All case reports, series, and review articles that were identified from this search were included. Selected cases of sinus barotrauma from our institution were included to illustrate classic signs and symptoms.

Results:

Fifty-one articles were identified as specifically relevant to, or referencing, barosinusitis and were incorporated into this review. The majority of articles focused on barosinusitis in the context of a single specific etiology rather than independent of etiology. From analysis of all the publications combined with clinical experience, we proposed that barosinusitis seemed to fall within three distinct subtypes: (1) acute, isolated barosinusitis; (2) recurrent acute barosinusitis; and (3) chronic barosinusitis. We introduced this terminology and suggested independent treatment recommendations for each subtype.

Conclusion:

Barosinusitis is a common but potentially overlooked condition that is primed by shifts in the ambient pressure within the paranasal sinuses. The pathophysiology of barosinusitis has disparate causes, which likely contribute to its misdiagnosis and underdiagnosis. Available literature compelled our proposed modifications to existing classification schemes, which may allow for improved awareness and management strategies for barosinusitis.

Prevention of Medical Events During Air Travel: A Narrative Review

Prior to traveling, and when seeking medical pretravel advice, patients consult their personal physicians. Inflight medical issues are estimated to occur up to 350 times per day worldwide (1/14,000-40,000 passengers). Specific characteristics of the air cabin environment are associated with hypoxia and the expansion of trapped gases into body cavities, which can lead to harm. The most frequent medical events during air travel include abdominal pain; ear, nose, and throat pathologies; psychiatric disorders; and life-threatening events such as acute respiratory failure or cardiac arrest. Physicians need to be aware of the management of these conditions in this unusual setting. Chronic respiratory and cardiovascular diseases are common and are at increased risk of acute exacerbation. Physicians must be trained in these conditions and inform their patients about their prevention.

Air travellers' awareness of the preventability of otic barotrauma

Objective:

Otic barotrauma is common among air travellers and can cause severe otalgia, perforation of the tympanic membrane and hearing loss. Many prevention measures exist, with varying evidence to support their use. There are no data to establish if air travellers are aware of them or indeed use them. We aimed to establish air travellers' knowledge of such prevention measures.

Methods:

We surveyed air travellers at two UK airports by means of a questionnaire. Answers to the questionnaire were collected over a two-week period.

Results:

Overall, 179 air travellers with a mean age of 28 years (range: 15–72 years) completed the questionnaire. There were 66 female and 113 male air travellers. The majority (84 per cent) complained of symptoms while flying and 30 per cent were not aware of any prevention measures. Barotrauma-related symptoms were reported in 25 per cent of air travellers who were unaware of any prevention measures. Nearly all air travellers (86 per cent) indicated that more information regarding prevention measures would be useful.

Conclusion:

Air travellers are often not aware of prevention measures to avoid otic barotrauma, and the majority suffer as a result. Increasing public awareness of simple prevention measures would have a significant impact on air travellers.

Passenger well-being in airplanes

Passenger well-being is influenced by cabin environmental conditions which interact with individual passenger characteristics like age and health conditions. Cabin environment is composed of different aspects, some of which have a direct influence on gastrointestinal functions and may directly generate nausea, such as cabin pressure, oxygen saturation, and motion or vibration. For example, it has been shown that available cabin pressure during normal flight altitude can significantly inhibit gastric emptying and induce dyspepsia-like symptoms when associated with a fibre-rich meal. Other aspects of the cabin environment such as space and variability of seating, air quality, and noise, also have been shown to modulate (reduce or increase) discomfort and nausea during flights. Individual passenger characteristics and health status also have been demonstrated to increase vulnerability to adverse health outcomes and discomfort.

Travel with infants and children

The risks faced by children traveling internationally may be minimized by providing and applying advice about comfort, safety, skin protection, and food and water hygiene. Prior to travel, children should be current on standard immunizations and may receive several specialized vaccines. Antibiotics for the presumptive treatment of travelers' diarrhea are usually indicated, and malaria chemoprophylaxis may be safely administered even to young children. Evaluation and care following prolonged stays in foreign countries can decrease the burden of imported disease.

A double-blind comparison between oral pseudoephedrine and topical oxymetazoline in the prevention of barotrauma during air travel

To determine the efficacy of two decongestants (oral pseudoephedrine versus topical oxymetazoline) in the prevention of middle ear barotrauma during air travel, 150 adult volunteers with a history of ear pain during air travel were entered into a randomized, double-blind study conducted at two commercial airports. Each subject received 120 mg pseudoephedrine, oxymetazoline hydrochloride (0.05%), or a double placebo (capsule and nasal spray) administered 30 minutes before flight departure. After arrival at their final destinations, volunteers were asked to complete a questionnaire and return it by mail to investigators. Questions included the intensity and duration of otologic symptoms experienced while flying and possible drug side effects. A total of 124 subjects completed the study; 41 received 120 mg of pseudoephedrine, 42 received oxymetazoline nasal spray, and 41 received a double placebo (capsule and nasal spray). The three treatment groups were similar with regard to age, sex, medical history, and flight profile. Symptoms of barotrauma were reported by 34% of those receiving pseudoephedrine versus 71% of the control group, for a relative risk reduction of 52% (95% confidence interval [CI] 33% to 71%). In contrast, 64% of the oxymetazoline group reported symptoms of barotrauma, for a relative risk reduction of 10% (95% CI, 3% to 17%). These results suggest that treatment with 120 mg pseudoephedrine at least 30 minutes before flying appears to decrease the incidence of barotrauma. Oxymetazoline nasal spray is little more effective than placebo in reducing ear pain and discomfort associated with changing ambient pressures.

Medical emergencies in commercial air travel

There are physiologic and logistic concerns involved in caring for patients with inflight emergencies. This article presents the physiologic changes that occur at altitude, the types of medical problems that can be encountered, and management strategies. An overview is also presented of the medical training of flight attendants and the medical equipment that is available on commercial aircraft.