Cough induced stress fracture and arthropathy of the ribs at extreme altitude

Life-Threatening and Non-Life-Threatening Complications Associated With Coughing: A Scoping Review

BACKGROUND

This is an update of the section on complications that are associated with coughing in the 2006 CHEST cough guidelines that addresses two aims: (1) to systematically identify and thematically categorize the diverse complications of cough by providing a guide for future studies and (2) to identify gaps in the literature for future research.

RESEARCH QUESTION

What are the potential complications that are associated with the act of coughing that have been reported in infants, children, adolescents, and adults?

STUDY DESIGN AND METHODS

A scoping review was performed with the use of PubMed and SCOPUS databases that were searched from their beginning until September 6, 2019.

RESULTS

Two hundred forty-seven publications met our inclusion criteria. To these, we added 38 articles from the 2006 complications paper that were not identified in the literature search plus the paper itself for a final total of 286 publications that formed the basis of this review. Since 2006, three new categories of complications have been reported: ear, nose and throat; disease transmission; and laboratory testing. Multiple additional complications that fall outside of these three categories have also been identified and included in the following categories: cardiovascular, constitutional symptoms, dermatologic, GI, genitourinary, musculoskeletal, neurologic, ophthalmologic, psychosocial/quality of life, and respiratory. Not previously highlighted is that some of the complications led to serious morbidity that included death, especially in patients with comorbid conditions, and potentially resulted in harm to others when cough resulted in a motor vehicle accident.

INTERPRETATION

Our work identified a large number of cough complications that we thematically categorized primarily by organ system so that future studies of each system or each complication can be conducted. The gap in the literature that future studies should address is to identify the frequency of the complications and the strength of their association with cough. Only then will one be able to describe the findings in a manner that allows specific recommendations for avoiding these complications. In the meantime, patients with cough should be evaluated and treated according to evidence-based guidelines to mitigate or prevent the myriad of potential complications that are associated with coughing.

Altitude-related cough

Altitude-related cough is a troublesome condition of uncertain aetiology that affects many visitors to high altitude. The traditionally held belief that it was due solely to the inspiration of cold, dry air was refuted by observations and experiments in long duration hypobaric chamber studies. It is likely that altitude-related cough is a symptom of a number of possible perturbations in the cough reflex arc that may exist independently or together. These include loss of water from the respiratory tract; respiratory tract infections and sub-clinical high altitude pulmonary oedema. The published work on altitude-related cough is reviewed and possible aetiologies for the condition are discussed.

Australian senior adventure travellers to Peru: Maximising older tourists' travel health experience

Financially comfortable, with ample spare time and much better health, older people travel more than ever and to more adventurous destinations. Taking Australian senior adventure travellers to Peru as an example, travel health preparations need to take into account the phenomenon 'senior traveller', the destination with its attractions and challenges, and age-related changes and restrictions. The need for routine travel health advice, vaccinations and prophylaxis remains unchanged. However, more emphasis should be placed on locality-specific issues so that age-appropriate advice and preparations maximize the chances for a safe and memorable travel experience.

Capsaicin exposure elicits complex airway defensive motor patterns in normal humans in a concentration-dependent manner

The airway defensive response to tussive agents, such as capsaicin, is frequently assessed by counting the number of cough sounds, or expulsive events. This method does not identify or differentiate important respiratory events that occur in the respiratory muscles and lungs, which are critical in assessing airway defensive responses. The purpose of this study was to characterize the airway defensive behaviours (cough and expiration reflex) to capsaicin exposure in humans. We observed complex motor behaviours in response to capsaicin exposure. These behaviours were defined as cough reacceleration (CRn) and expiration reflex (ERn), where n is the number of expulsive events with and without a preceding inspiratory phase, respectively. Airway defensive responses were defined in terms of frequency (number of expulsive events), strength (activation of abdominal muscles) and behaviour type (CRn vs. ERn). Thirty-six subjects (15 females, 24+/-4 yr) were instrumented with EMG electrodes placed over the rectus abdominis (RA), external abdominal oblique (EO) and the 8th intercostal space (IC8). A custom-designed mouth pneumotachograph was used to assess the airflow acceleration, plateau velocity and phase duration of the expulsive phase. Subjects inhaled seven concentrations of capsaicin (5-200 microM) in a randomized block order. The total number of expulsive events (frequency) and the sum of integrated EMG for the IC8, RA and EO (strength) increased in a curvilinear fashion. Differentiating the airway defense responses into type demonstrated predominately CR1 and CR2 (i.e. inspiration followed by one and two expulsive events, respectively) with very few ER's at <50 microM capsaicin. At higher concentrations (>50 microM) ER's with one or more expulsive events (ER1) appeared, and the number of CR's with three or more expulsive events (CR3) increased. The decrease in EMG activation and airflow measurements with each successive expulsive event suggests a decline in power and shear force as the number of expulsive events increased. Therefore, the airway defensive response to capsaicin is a complex motor pattern that functions to coordinate ER's and CR's with differing numbers of expulsive events possibly to prevent aspirations and keep air moving to promote clearance.

Altitude-related cough

Cough is a troublesome condition which affects many visitors to high altitude. Traditionally it has been attributed to the inspiration of the cold, dry air which characterizes the high altitude environment. This aetiology was brought into question by observations and experiments in long duration hypobaric chamber studies in which cough still occurred despite controlled temperature and humidity. Anecdotally however, exercise, possibly via the associated increase in ventilation, does appear to precipitate cough at altitude. It is likely that the term, altitude-related cough, covers a number of conditions and aetiologies. These aetiologies are discussed and include water loss from the respiratory tract; high altitude pulmonary oedema; acute mountain sickness; bronchoconstriction; respiratory tract infections; vasomotor rhinitis and post-nasal drip; and alterations in the central control of respiration. We hypothesize that there are two forms of altitude-related cough: a cough which may occur at relatively low altitudes and which is related to exercise and persists despite descent and a cough which does not occur at altitudes below 5000-6000 m and which improves rapidly with descent to lower altitude. The treatment of altitude-related cough is symptomatic and frequently ineffective. Further work is required to understand the nature and aetiology of the cough which occurs at high altitude before effective therapies can be developed.

Uncommon causes of cough: ACCP evidence-based clinical practice guidelines

OBJECTIVES

To describe the uncommon causes of cough.

DESIGN/METHODOLOGY

An English language literature search by MEDLINE citations from 1975 through 2004 was used to identify publications on uncommon pulmonary and nonpulmonary disorders in which cough was present as the major or presenting symptom in >50% of those persons affected by the uncommon diseases.

RESULTS

A substantial number of uncommon or rare pulmonary and nonpulmonary disorders were identified. The uncommon occurrence of these diseases made it difficult to develop a meaningful evidence-based guideline to the diagnosis and therapy of many of the uncommon causes of cough. As cough was the major or presenting symptom, it was usually initially attributed to common respiratory diseases (eg, asthma or bronchitis). As a result, a substantial time lag existed from the onset of cough to the diagnosis of the etiologic entity. Diagnostic tests limited to the respiratory system did not always provide clues to the diagnosis of uncommon causes of cough.

CONCLUSIONS

Cough is the major or presenting symptom in many uncommon pulmonary and nonpulmonary disorders. A strong index of suspicion is essential to consider and diagnose the uncommon causes of cough. The diagnosis and management of cough in patients with uncommon causes of cough is dependent on the underlying etiology.

Environmental insults: smoke inhalation, submersion, diving, and high altitude

In the expanding search for recreation, we spend more and more of our time in various environments. Whether the air is thin or compressed or smoke-filled or there is no air at all, emergency physicians continue to meet and treat the various pulmonary emergencies that the environment may create. The authors present the background, diagnosis, and management of a few of the more common pulmonary emergencies that the environment may produce.

Rib fractures induced by coughing: an unusual cause of acute chest pain

We report three patients with stress fractures of the ribs induced by coughing. Standard radiographs of the chest and ribs did not reveal evidence of rib fractures in any of the patients. Bone scintigraphy, performed 1 to 2 weeks after initial onset of symptoms, showed a focal area of increased uptake along the chest wall in all cases. Thin section angulated helical CT directly visualized the subtle rib fractures. Initial diagnosis of a cough-induced fracture of the rib may be difficult because of the associated underlying disorder, and unnecessary examinations are commonly performed. Identification of a cough-induced fracture of the rib using helical CT may be clinically important to avoid unnecessary concern and additional examinations.