bluuebunny/crossref_metadata_2025 huggingface dataset:
Emerging Role of PET in the Diagnosis and Staging of Lung Cancer
Authors: Coates Geoffery , Skehan Stephen J
Published: March 2016

Positron emission tomography (PET) with 18F‐fluoro‐2‐deoxyglucose (FDG) has recently emerged as a practical and useful imaging modality in patients with lung cancer. Malignant tumours demonstrate increased uptake of FDG, a positron‐emitting radiopharmaceutical. This increased FDG uptake in tumours can be seen using PET. FDG PET has much higher accuracy than other imaging modalities for the differentiation of benign and malignant lung nodules. The sensitivity of PET is 96% and the specificity 77% for diagnosing malignant nodules. PET is also more accurate than computed tomography (CT) for staging mediastinal nodal involvement (sensitivity 89%, specificity 94%). While CT relies on an arbitrary anatomical cutoff of 1 cm to diagnose malignant nodes, which may simply be enlarged due to inflammation, PET can accurately diagnose metastases in nodes smaller than 1 cm. Several studies have shown significantly better staging of distant metastases with FDG PET than with traditional techniques such as bone scanning. Differentiation of recurrent disease from scar tissue in the postoperative patient is often difficult with CT or magnetic resonance imaging. The low uptake of FDG in scar tissue allows reliable differentiation between scar tissue and a recurring tumour with PET. Early studies suggest a promising role for PET in the evaluation of response to chemotherapy. This may allow treatment to be changed after only one course of chemotherapy, instead of waiting for anatomical disease progression to become obvious clinically or with CT. Finally, significant improvements in cost effectiveness have been demonstrated when FDG PET is added to the preoperative work‐up of patients with lung cancer.
Neonatal and Maternal Postpartum Bacteroides Bacteremia
Authors: Zaker Nahid , Lertzman Joy , Embree Joanne
Published: March 2016

OBJECTIVE: A unique case of Bacteroides fragilis bacteremia in a mother and her infant prompted a review of these infections in neonates and postpartum mothers during a five‐year period at two institutions in Winnipeg, Manitoba. The purpose was to determine the frequency of these infections and ascertain commonly associated factors.

METHODS: Infants and postpartum mothers diagnosed with bacteroides bacteremia were identified from laboratory records in both hospitals, and their medical charts were retrospectively reviewed.

RESULTS: Bacteroides species were isolated in 10 maternal and four neonatal blood cultures. This represented 8.1% of the positive maternal and 1.2% of the positive neonatal blood cultures obtained during the review. The incidence of maternal infection was 2.56/10,000 deliveries, while that of neonatal infection was 1.03/10,000 live births. Postpartum fever and emergency caesarean section were often noted with maternal postpartum bacteroides bacteremia, while fetal distress, low Apgar scores and respiratory distress were frequent in neonatal bacteremia.

CONCLUSION: Postpartum bacteroides bacteremia should be suspected among women with postpartum fever after emergency caesarean section. However, the occurrence of postpartum fever following emergency caesarian section is not necessarily associated with neonatal bacteroides bacteremia. Neonatal bacteroides bacteremia may not be readily suspected on clinical grounds, so clinicians should ensure that the laboratory procedures routinely used to evaluate neonatal bacteremia at their institutions reliably detect these organisms.
Determinants of Tuberculin Reactivity among Health Care Workers: Interpretation of Positivity following BCG Vaccination
Authors: Mckay Andrew , Kraut Allen , Murdzak Carol , Yassi Annalee
Published: March 2016

OBJECTIVE: To determine the extent to which a history of Bacille Calmette‐Guerin (BCG) vaccination influences the likelihood of positive tuberculin skin test (TST) results.

DESIGN: Cross‐sectional survey using a hospital‐based tuberculosis surveillance program.

SETTING: Health Sciences Centre, a tertiary care hospital in Winnipeg, Manitoba.

METHODS: The 476 health care workers (HCWs) who had TST as part of the surveillance program between 1993 and 1997 constituted the study population. The two‐step test was done in 91% of the participants who did not have a positive initial test, defined as 10 mm or greater of induration. Data were gathered through chart review supplemented by a short questionnaire administered to the HCWs.

MAIN RESULTS: One hundred and thirty‐eight HCWs (29%) had a positive TST. In a stepwise, multiple logistic model controlling for age, sex, job title, work area, age of receiving BCG, time since BCG and duration of employment, only a history of BCG vaccination (odds ratio [OR] 22; 95% CI 12 to 41) and birth outside of Canada (OR 2.6; 95% CI 1.4 to 5.8) were significantly associated with a positive TST. When the definition of a positive TST was modified by increments of 1 mm, from 10 mm up to 20 mm of induration in BCG recipients, BCG was associated with positive reactions with indurations up to 19 mm but not 20 mm or greater. The OR declined with each increment. Of the 84 HCWs who were documented to have at least 20 years between BCG vaccination and testing, 41 (49%) had positive reactions.

CONCLUSIONS: BCG vaccination can produce lasting tuberculin reactivity, and indurations of 19 mm or less may be due to the effects of the vaccine.
Characterization and Proposed Nomenclature of Epidemic Strains of MRSA in Canada
Authors: Simor AE , Boyd D , Louie L , McGeer A , Mulvey M , Willey BM , the Canadian Hospital Epidemiology Committee  , the Canadian Nosocomial Infection Surveillance Program
Published: March 2016

The incidence of methicillin‐resistant Staphylococcus aureus (MRSA) has been increasing in many Canadian hospitals over the past few years. Some strains may be considered ‘epidemic’, in that they are clinically or epidemiologically significant, and have been identified in patients from multiple hospitals and geographic regions across the country. This paper describes phenotypic and genotypic characteristics of four epidemic MRSA strains in Canada and proposes standardized nomenclature.
Spontaneous Regression of Multiple Emphysematous Bullae
Authors: Satoh Hiroaki , Suyama Tokihiko , Yamashita Yuko T , Ohtsuka Morio , Sekizawa Kiyohisa
Published: March 2016

The etiology of emphysematous bullae is not well known; thus, the management of bullous lung disease is often difficult because of concomitant underlying emphysema and coexisting cardiac conditions. The present paper reports a case in which near complete resolution of multiple emphysematous bullae in the right lung occurred spontaneously. This case is of interest, not only because of the rarity with which spontaneous regression of multiple emphysematous bullae has been reported in the literature, but also because of the accompanying dramatic improvements in radiological results and pulmonary function of the patients.
Occupational Neutrophilic Asthma
Authors: Leigh Richard , Hargreave Frederick E
Published: March 2016

Occupational asthma is typically associated with an eosinophilic bronchitis. The case of a 41‐year‐old woman who developed symptoms of asthma after occupational exposure to metal working fluids is reported. The diagnosis of asthma was confirmed by an forced expiratory volume in 1 s (FEV1) of 1.7 (59% predicted), with 11% reversibility after inhaled bronchodilator and a provocation concentration of methacholine to cause a fall in FEV1 of 20% (PC20) of 0.4 mg/mL. Induced sputum examination showed a marked neutrophilia. Over the next six months, serial sputum analyses confirmed the presence of a marked sterile neutrophilic bronchitis during periods of occupational exposure to metal working fluids, which resolved when the patient was away from work and recurred when she returned to work. The sputum findings were mirrored by corresponding changes in spirometry and PC20 methacholine. The findings indicate the occurrence of occupational asthma associated with an intense, sterile neutrophilic bronchitis after exposure to metal working fluids.
Health Care Costs Associated with Acute Asthma: A Prospetive Economic Analysis
Authors: Behbehani Naser Awadh , Grunfeld Anton , FitzGerald J Mark
Published: March 2016

OBJECTIVE: To determine the direct and indirect costs associated with the care of acute asthma in an adult teaching hospital.

DESIGN: A prospective, cost identification study.

PATIENTS AND METHODS: Patients aged 15 to 55 years presenting with acute asthma. Consecutive emergency department visits for asthma at Vancouver Hospital and Health Sciences Centre over six months were prospectively monitored. The duration of hospital stay, physician?s care, laboratory procedures and medication given were recorded. Time lost from work or school was determined by follow‐up telephone calls. The costs were calculated in 1997 Canadian dollars.

RESULTS: One hundred and forty‐nine patients made 195 emergency department visits over the six‐month study. Twenty‐eight (14%) of these visits led to hospital admissions. The total cost associated with the care of these patients was $250,570. The median (standard deviation in brackets) direct medical costs associated with each emergency department visit and hospital day were $324.00 (±52.00) per visit, and $677.00 (±76.00) per day, respectively.

CONCLUSION: The present study provides a more accurate estimation of the operational cost of managing asthma in a teaching hospital setting than previous studies. The data presented in this study can be used in future cost effectiveness and cost‐benefit studies in acute asthma, particularly where these studies involve specific intervention such as asthma education. More studies, which include children with asthma and patients treated outside of the hospital setting, are needed.
Inhaled Glucocoriticoids in Children: A Facourable Therapeutic Index
Authors: Simons F Estelle R
Published: March 2016

In children with persistent asthma, inhaled glucocorticoids decrease symptoms and exacerbations, decrease the need for rescue bronchodilator medications, improve airway patency and reduce airway hyperresponsiveness. When administered in the lowest doses that prevent symptoms and eliminate the need for supplemental courses of oral glucocorticoids, they are unlikely to cause clinically important systemic adverse events. Inhaled glucocorticoids have a favourable risk to benefit ratio in this population.
Empyema Caused by Clostridium difficile
Authors: Hudson Darren A , Gibb A Patrick , Gill M John
Published: March 2016

Extraintestinal infections of Clostridium difficile are rare and often associated with underlying disorders. A case of empyema caused by aspiration of C difficile in a patient with carcinoid syndrome and C difficile colitis is described.
Number 2: Chronic Obstructive Pulmonary Disease: The Importance of Exercise
Authors: Jones Norman L
Published: March 2016

Patients with chronic obstructive pulmonary disease (COPD ‐ chronic bronchitis, emphysema, asthma) are often limited in their capacity to exercise, mainly because they experience shortness of breath or muscle fatigue. The reasons for shortness of breath are dealt with in another patient page (Can Respir J 2000;7(1):35‐36), and include narrowing of the airways, poor lung function leading to falls in the amount of oxygen carried in the blood and weak muscles for breathing. Easy fatiguability may be because of muscle weakness or changes in muscle function, related to inactivity and ageing. Other less common factors include heart problems associated with COPD, and other coexisting health problems, such as anemia and arthritis.
Hospitalization due to Adverse Drug Reactions and Drug Interactions before and after HAART
Authors: Foisy Michelle M , Gough Kevin , Quan Corinna M , Harris Kevin , Ibanez Dominique , Phillips Anne
Published: March 2016

OBJECTIVE: To characterize and compare the rates of adverse drug reactions (ADRs) and interactions on admission in two, one‐year periods: pre‐highly active antiretroviral therapy (HAART) (phase 1) and post‐HAART (phase 2).

DESIGN: Retrospective chart review.

SETTING:University‐affiliated tertiary care centre.

POPULATION STUDIED: HIV‐positive patients admitted to hospital.

MAIN RESULTS: In phase 1, 436 of 517 admissions, and, in phase 2, 323 of 350 admissions were analyzed. Over 92% of patients were male, with a mean age of 38 years. Significant differences (P<0.05) in the mean length of stay (12.08 versus 10.02 days), the CD4 counts (99.25 versus 129.45) and the number of concurrent diseases (4.20 versus 3.63) were found between phase 1 and 2, respectively. The mean number of medications taken (5.52 versus 5.94) and the rates of hospitalization with ADRs (20.4% versus 21.4%) or interactions (2.5% versus 2.16%) were similar between the two phases. Antiretrovirals were more common in ADR admissions post‐HAART (21.3% versus 36.2%), while antiparasitics, psychotherapeutics and antineoplastics were more common pre‐HAART. Other classes of drugs involved in both phases were sulphonamides, narcotics, ganciclovir, foscarnet, antimycobacterials and antifungals. ADR causality was possible or probable in more than 80% of cases. Over 60% of ADRs were grades 3 to 4, and about 85% were either the main or contributing reason for admission. About 65% of patients had at least partial recovery at the time of discharge. In phases 1 and 2, 8.9% and 2.9% of admissions,respectively, with ADRs were fatal.

CONCLUSIONS: Although hospitalizations with ADRs and interactions were similar in both phases, HAART therapy has had a significant impact on the incidence and nature of ADRs at St Michael?s Hospital, Wellesley Central Site, Toronto, Ontario.
Rhinoviruses as Pathogens of the Lower Respiratory Tract
Authors: Papadopoulos Nikolaos G , Johnson Sebastian L
Published: March 2016

Rhinoviruses (RVs) are the most common upper respiratory pathogens, inducing the majority of common colds worldwide. RV-related morbidity, although significant cumulatively, has been considered trivial for the individual patient. However, recent strong epidemiological associations of RVs with asthma exacerbations, including severe episodes requiring hospitalization, indicate that RV infections can result in serious disease. Current evidence supports the possibility that RVs infect the lower airways, inducing a local inflammatory response. Such evidence suggests that the role of RVs in other lower respiratory diseases, such as pneumonia, bronchitis, bronchiolitis and cystic fibrosis, should be re-examined with polymerase chain reaction-based methodologies, which are considerably more sensitive than traditional, cell culture-based techniques. The mechanisms through which RVs induce lower airway disease are studied to understand the relative contributions of the epithelial, neurogenic and immune components in the antiviral response, and to permit the design and implementation of specific treatments.
Keeping Up-to-Date
Authors: Jones Norman L
Published: March 2016

As a senior (read older) practising respirologist, I have come to appreciate my position as editor, which keeps me current with present practice standards. Everyone talks about the volume and flow of new knowledge, and not a week goes by in which I feel that I know enough to treat my patients optimally. This is particularly the case when it comes to antibiotic usage: the number of antibiotics and the confident way that junior colleagues bandy them about leaves me distinctly depressed because most of the names mean little to me; even the families and generations of antibiotics seem beyond my grasp. That is why I welcomed the request from Dr Lionel Mandell to publish a summary statement on the use of antibiotics in community-acquired pneumonia (CAP), which appears on pages 371-382 of the current issue of theCanadian Respiratory Journal.
Clinical Trials: New Developments
Authors: Boulet Louis-Philippe
Published: March 2016

Canadian respiratory health research is recognized as being among the best worldwide. Many Canadian researchers are leaders in international projects, including large scale clinical trials. There is, however, a need to develop a structure that could foster the collaboration of Canadian investigators in joint projects of this sort. In the past few years, discussions have taken place on what could be a Canadian Thoracic Society (CTS) Clinical Trials Group. This is a wonderful opportunity to put forward such an initiative, in the context of the new Canadian Institutes of Health Research (CIHR), where this type of collaborative activity fits quite well with the goals of this new institution.
Varicella Susceptibility in a Canadian Population
Authors: Ratnam Sam
Published: March 2016

OBJECTIVE: To determine susceptibility to varicella zoster virus (VZV) infection among children, pregnant women and health care workers in Newfoundland.

DESIGN: Cohort and cross‐sectional, province‐wide, population‐based seroprevalence study.

STUDY POPULATION AND METHODS: A cohort of 586 children aged one year, a cross‐sectional group of 1135 school children aged five to 15 years, 3643 pregnant women aged 15 to 45 years, and 5386 persons in health care settings aged 15 to 55 years. Susceptibility to varicella was determined by enzyme immunoassay based on serum antibody to VZV.

RESULTS: Among the cohort of 586 children, 565 (96.4%) did not have detectable VZV antibody at one year of age. The proportion with VZV antibody increased thereafter to 12.8% and 33.9%, respectively, at age two and four years, indicating the extent of exposure to VZV at these ages. Among the 1135 school‐age children, the proportion testing positive for VZV antibody increased from 44% at five years of age to 88.9% at 15 years of age, indicating the cumulative incidence of varicella in this age group. Among pregnant women, 92.1% tested positive for VZV antibody, and the corresponding figure for the health care group was 93.1%. In both groups, the proportion testing positive for VZV antibody increased with advancing age, from 89.6% for the 15‐ to 19‐year age group to 96.5% for those over the age of 40 years.

CONCLUSIONS: The risk of VZV infection increases steadily from one year of age, reaching a peak during school years. The study data support the recent Canadian recommendation to vaccinate any person older than 12 months of age who is susceptible to VZV. Among the adult population, the proportion susceptible will be under 10% for the foreseeable future, and for those at risk, selective vaccination based on their immune status would be a cost effective approach.
Protective Effects of Fluticasone on Allergen‐Induced Airway Responses and Sputum Inflammatory Markers
Authors: Parameswaran Krishnan , Inman Mark D , Watson Rick M , Morris Marilyn M , Efthimiadis Ann , Ventresca Pietro G , Lam Raymond , O′Byrne Paul M , Hargreave Frederick E
Published: March 2016

BACKGROUND: A direct comparison of the protective effects of single and regular doses of inhaled glucocorticoid on allergen‐induced asthmatic responses and inflammation has not been made.

OBJECTIVE: To compare the effects of pretreatment with fluticasone 250 µg 30 min before allergen inhalation and two weeks of 250 µg twice daily (last dose 24 h before challenge) with single and regular (twice daily) placebo doses on early and late asthmatic responses, induced sputum cell counts and measures of eosinophil activation at 7 h and 24 h, and methacholine airway responsiveness at 24 h.

PATIENTS AND METHODS: Ten mild asthmatic patients were studied in a randomized, double‐blind, placebo controlled crossover study.

RESULTS: Regular fluticasone increased the baseline mean provocative concentration of methacholine to cause a 20% fall (PC20) in forced expiratory volume in 1 s (FEV1) from 2.6 to 6.4 mg/mL (P<0.05) and lowered the eosinophil count from 3.1% to 0.4% (P<0.05) compared with regular placebo. Neither single nor regular fluticasone had any effect on the early asthmatic response. Single fluticasone attenuated the late asthmatic response, the mean ± SEM maximum percentage fall in FEV1 (10.8±3.6 compared with single placebo 18.8±3.5, P=0.03), the allergen‐induced increase of airway responsiveness (P<0.05), and the eosinophilia (P<0.005) and activated eosinophils at 7 h (P<0.01) but not at 24 h. Regular fluticasone also attenuated the late asthmatic response (11.1±2.5) compared with regular placebo (19.6±4.5), but this was not statistically significant and did not protect against the induced increase in airway responsiveness or the sputum eosinophilia.

CONCLUSION: Two weeks of regular inhaled fluticasone discontinued 24 h before allergen challenge does not offer any additional protection against the early or late asthmatic responses, increased airway responsiveness or sputum eosinophilia compared with a single dose of 250 µg immediately before allergen challenge, despite increasing baseline PC20 and decreasing sputum eosinophilia prechallenge. The significance of the protective effect of a single dose of inhaled steroid before an allergen inhalation and the duration of the protective effect need further investigation.
Why Read the Classics?
Authors: Jones Norman L
Published: March 2016

With the editorial staff of the Canadian Respiratory Journal, I extend our best wishes for the New Year, and heartfelt thanks to everyone who has helped the Journal establish itself in the competitive field of quality, peer‐reviewed publications in chest medicine. It may seem odd to start the new millennium with an editorial eulogizing the past, but even in these ′postmodern′ days of chaos, complexity and ordered unpredictability, the past can be seen to have a huge influence on the present and the future. The importance of looking back on work that has influenced our present views on chest medicine, and why, was the main reason for the series inaugurated in the present issue ‐ ′Modern Classics Revisited′ (pages 71‐76).
Spinal NGF Restores Opioid Sensitivity in Neuropathic Rats: Possible Role of NGF as a Regulator of CCK‐Induced Anti‐Opioid Effects
Authors: Cahill Catherine M , Coderre Terence J
Published: March 2016

The breadth of peripheral effects produced by nerve growth factor (NGF) in nociceptive processing has been well documented. However, less is known about the functional significance of central NGF in nociceptive transmission. The effect of NGF on the nervous system is dependent on the developmental stage. During the prenatal developmental period, NGF is critical for survival of nociceptors; in the postnatal period it regulates the expression of nociceptor phenotype, and in the adult it contributes to pain following an inflammatory insult. The implications for central NGF in the expression and regulation of spinal neuropeptides that are involved in pain mechanisms are reviewed. Knowledge has been gained by studies using peripheral nerve injury models that cause a deprivation of central NGF. These models also give rise to the development of pain syndromes, which encompass spontaneous pain, hyperalgesia and allodynia, routinely referred to as neuropathic pain. These models provide an approach for examining the contribution of central NGF to nociceptive transmission. Chronic pain emanating from a nerve injury is typically refractory to traditional analgesics such as opioids. Recent evidence suggests that supplementation of spinal NGF restores morphine‐induced antinociception in an animal model of neuropathic pain. This effect appears to be mediated by alterations in spinal levels of cholecystokinin. The authors hypothesize that NGF is critical in maintaining neurochemical homeostasis in the spinal cord of nociceptive neurons, and that supplementation may be beneficial in restoring and/or maintaining opioid analgesia in chronic pain conditions resulting from traumatic nerve injury.
Outpatient Antibiotic Therapy and Short Term Mortality in Elderly Patients with Chronic Obstructive Pulmonary Disease
Authors: Sin Don D , Tu Jack V
Published: March 2016

OBJECTIVES: To determine the association between outpatient use of oral antibiotics and 30‐day all‐cause mortality following hospitalization in a group of elderly chronic obstructive pulmonary disease (COPD) patients.

DESIGN: A population‐based retrospective cohort study.

SETTING: Ontario, Canada.

POPULATION STUDIED: All 26,301 patients, 65 years of age or older, who were hospitalized for COPD between 1992 and 1996 in Ontario.

METHODS: All elderly patients admitted at least once with a most responsible diagnosis of COPD using the Canadian Institute for Health Information database were identified. They were then linked to the Ontario Drug Benefit database to determine the use of antibiotics within 30 days of the index hospitalization and to the Ontario registered persons database to determine the 30‐day mortality following their index hospitalization.

RESULTS: Outpatient use of antibiotics within 30 days before the index hospitalization was associated with a significant reduction in the 30‐day mortality following hospitalization (odds ratio [OR] 0.83, 95% CI 0.75 to 0.92). Use of macrolides had the lowest relative odds for mortality (OR 0.58, 95% CI 0.47 to 0.73), while use of fluoroquinolones had the highest relative odds (OR 0.98, 95% CI 0.84 to 1.15).

CONCLUSIONS: Use of antibiotics before hospitalization was associated with a significant reduction in the risk of short term mortality among a group of elderly COPD patients who eventually required hospitalization for their disease. These findings support the early use of antibiotics in COPD patients who experience an acute exacerbation.
Thoracic Complications of Lemierre Syndrome
Authors: Gowan Russell Thomas , Mehran Reza John , Cardinal Pierre , Jones Gwynne
Published: March 2016

Lemierre syndrome is a severe, septicemic illness most commonly caused by the anaerobic Gram‐negative bacillus Fusobacterium necrophorum. It is characterized by an acute oropharyngeal infection, with secondary septic thrombophlebitis of the internal jugular vein and frequent metastatic infections. This report of a patient with the Lemierre syndrome is complemented by a review of the literature on the subject.
Summary of Canadian Guidelines for the Initial Management of Community‐Acquired Pneumonia: An Evidence‐Based Update by the Canadian Infectious Disease Society and the Canadian Thoracic Society
Authors: Mandell Lionel A , Marrie Thomas J , Grossman Ronald F , Chow Anthony W , Hyland Robert H , Canadian CAP Working Group
Published: March 2016

Community‐acquired pneumonia (CAP) is a serious illness with a significant impact on individual patients and society as a whole. Over the past several years, there have been significant advances in the knowledge and understanding of the etiology of the disease, and an appreciation of problems such as mixed infections and increasing antimicrobial resistance. The development of additional fluoroquinolone agents with enhanced activity against Streptococcus pneumoniae has been important as well. It was decided that the time had come to update and modify the previous CAP guidelines, which were published in 1993. The current guidelines represent a joint effort by the Canadian Infectious Diseases Society and the Canadian Thoracic Society, and they address the etiology, diagnosis and initial management of CAP. The diagnostic section is based on the site of care, and the treatment section is organized according to whether one is dealing with outpatients, inpatients or nursing home patients.
Influenza Vaccinationfor Health Care Workers: A Duty of Care
Authors: Orr Pamela
Published: March 2016

The medical literature has amply documented the transmission of influenza from patients to health care workers (HCWs) (1,2), from HCWs to patients (3) and between HCWs (4‐9). The consequences of influenza transmission within the health care environment include morbidity and mortality among patients, most of who are at high risk for the complications of infection, and illness and absenteeism among health care providers. When outbreaks occur in health care facilities, absenteeism among HCWs may approach 30% to 40%, resulting in severe staff shortages, increased employment costs and the potential endangerment of health care delivery due to the scarcity of replacement workers (10‐13).
New Challenges for the Canadian Thoracic Society
Authors: Boulet Louis-Philippe
Published: March 2016

I have been thinking for a while about what I would write in this editorial when I became president of the Canadian Thoracic Society (CTS). I found that it was really an opportunity, although a demanding task to take this position in the year 2000 in a rapidly changing world that is not short of new but exciting challenges. The marked progress in communications, the increased public awareness of respiratory health and environmental issues, the development of new technologies, changes in traditional ways to support research and the increasing demand on practitioners to acquire new knowledge and abilities makes it an unprecedented environment that asks us to rethink the way we used to do research and practice medicine.
Surgical Treatment of Chronic Thromboembolic Pulmonary Hypertension
Authors: Rubens Fraser , Wells Phil , Bencze Steven , Bourke Michael
Published: March 2016

BACKGROUND: There are only limited treatment options for patients with chronic thromboembolic pulmonary hypertension in Canada.

OBJECTIVE: To conduct a case‐series study to assess the effectiveness of surgical endarterectomy of the pulmonary artery.

DESIGN AND SETTING: Twenty‐one patients with chronic thromboembolic pulmonary hypertension were admitted

for surgery between July 1995 and October 1999. Clinical, laboratory and radiological data were collected for all patients who then underwent pulmonary thromboendarterectomy.

MAIN RESULTS: Thirteen men and eight women between 22 and 71 years of age underwent surgery. The main presenting complaint was dyspnea on exertion. Pulmonary vascular resistance ranged from 382 to 1694 dynes·s·cm-5 with a mean of 765±372 dynes·s·cm-5 (normal is less than 180 dynes·s·cm-5) with a mean cardiac index of 2.2±0.9 L/min/m2. Two patients had concomitant tricuspid valve replacement and one patient had coronary bypass grafting. In three cases, the surgery involved a repeat sternotomy. After surgery, there was a significant drop in the pulmonary vascular resistance (208±92 dynes·s·cm‐5, P<0.05) and a concomitant rise in the cardiac index to a mean of 3.1±0.6 L/min/m2 (P<0.05). There was one death in a patient who also had severe chronic obstructive pulmonary disease. Of the remaining patients, all but two showed significant clinical improvement. Spiral computed tomography postsurgery demonstrated improvement in pulmonary perfusion with either complete clearing or significant improvement in the mosaic perfusion pattern. Right ventricular function and pressure on echocardiogram improved in all but two patients.

CONCLUSIONS: Pulmonary thromboendarterectomy provides effective treatment for chronic thromboembolic pulmonary hypertension.
Spinal Tolerance and Dependence: Some Observations on the Role of Spinal N‐Methyl‐D‐Aspartate Receptors and Phosphorylation in the Loss of Opioid Analgesic Responses
Authors: Yaksh Tony L , Hua Xiao-Ying
Published: March 2016

The continuous delivery of opiates can lead to a reduction in analgesic effects. In humans, as in other animals, some component of this change in sensitivity seems likely to have a strong pharmacodynamic component. Such loss of effect, deemed to be tolerance in the present article, can be readily demonstrated in animals with repeated bolus and continuous intrathecal infusion of mu and delta opioids and alpha‐2 adrenergic agonists. Research has shown that this loss of effect can be diminished by concurrent treatment with N‐methyl‐D‐aspartate (NMDA) receptor antagonists and by the suppression of the activity of spinal protein kinase C (PKC). This suggests in part the probable role of PKC‐mediated phosphorylation in the right shift in the dose‐effect curves observed with continuous opiate or adrenergic exposure. Importantly, this right shift is seen to occur in parallel with an increase in the phosphorylating activity in the dorsal horn and in the expression of several PKC isozymes. The target of this phosphorylation is not certain. Phosphorylation of the NMDA receptor enhances its functionality, while phosphorylation of the opioid receptor or associated channels seems to diminish their activity or to enhance internalization. While the focus is on several specific components, the accumulating data emphasize the biological complexity of these changes in spinal drug reactivity.
TNF‐α Dysregulation in Asthma: Relationship to Ongoing Corticosteroid Therapy
Authors: Waserman Susan , Dolovich Jerry , Conway Mary , Marshall Jean S
Published: March 2016

BACKGROUND: Tumour necrosis factor‐alpha (TNF‐α) is a major proinflammatory cytokine that is thought to be important in the pathogenesis of asthma. However, alterations in systemic regulation of this cytokine in asthma have not been examined in the context of corticosteroid therapy.

OBJECTIVES: To examine the ability of peripheral blood mononuclear cells (PBMC) from three different groups of patients with asthma requiring varying amounts of inhaled corticosteroids (ICS) for clinical control, and to examine cells from age‐ and sex‐matched nonasthmatic patients to produce TNF‐α.

DESIGN: All patients with asthma had a positive methacholine challenge test. ′High dose′ ICS patients with asthma required ICS greater than or equal to 800 µg/day. ′Medium dose′ patients with asthma were on less than or equal to 500 µg/day of ICS, whereas ′no ICS′ patients with asthma had received no ICS for at least three months. Each patient with asthma was examined in parallel with an age‐ and sex‐matched, nonasthmatic, nonatopic control subject. Cells were cultured (with or without the addition of potential stimulators phytohemagglutinin, lipopolysaccharide, formyl‐methionine‐leucine‐phenylalanine or antihuman CD3), and TNF‐α production was assessed by ELISA.

MAIN RESULTS:PBMC from both high dose ICS (n=8) and no ICS (n=11) patients with asthma produced more than twice the amount of TNF‐α than cells from matched nonasthmatic control patients (P<0.01) when cultured alone or in the presence of each stimulus (P<0.05). In contrast, there was no significant difference in TNF‐α production between medium dose ICS patients with asthma and control patients. A group of asymptomatic atopic patients (n=6) did not have an increased level of TNF‐α production.

CONCLUSIONS: Increases in TNF‐α production within the PBMC compartment can be observed in both patients with asthma receiving high dose ICS and in a group of patients with mild asthma receiving no ICS therapy, but not in patients with asthma receiving a medium dose of ICS or atopic patients.
Update on the Canadian Institutes of Health Research: Where Will Respiratory Health Research Fit in?
Authors: King Malcolm
Published: March 2016

My main focus as Canadian Thoracic Society (CTS) President has been on research. The centre of attention has, of course, been the soon‐to‐be‐established Canadian Institutes of Health Research (CIHR) and our Society′s efforts to establish a position for respiratory research withing this new organization.
Pharmacokinetic Interaction between Zidovudine and Trimethoprim/sulphamethoxazole in HIV‐1 Infected Children
Authors: Dallas Shannon , Read Stanley E , King Susan , Koren Gideon , Bendayan Reina
Published: March 2016

OBJECTIVE: To evaluate the effect of the antimicrobial agent trimethoprim/sulphamethoxazole (TMP/SMX) on the pharmacokinetic properties of the antiretroviral drug zidovudine (ZDV).

DESIGN: This single dose, open label, crossover study involved the oral administration of ZDV (150 mg/m2) alone and in combination with oral TMP/SMX (2.5 mg/kg) on two separate occasions. Serial blood samples (0 to 8 h) were collected, and concentrations of ZDV and its glucuronide metabolite were quantified using a radioimmunoassay. ZDV pharmacokinetics were determined by noncompartmental analysis.

PATIENTS AND SETTING: Six HIV‐1 infected children aged four months to five years were recruited from the HIV clinic at The Hospital for Sick Children, Toronto, Ontario. Only three patients completed both study phases and were included in the pharmacokinetic analysis.

MAIN RESULTS: With TMP/SMX therapy, no statistically significant changes were observed in ZDV pharmacokinetic parameters. However, there was a trend towards increased ZDV half‐life and area under the concentration versus time curve, as well as decreased apparent oral clearance. Similarly, a trend towards an increased half‐life of the ZDV‐glucuronide metabolite was also observed.

CONCLUSION: The changes in ZDV pharmacokinetics in the presence of TMP/SMX did not reach statistical significance, most likely due to the limited number of patients involved. Despite the limited data, a possible interaction between ZDV and TMP/SMX in young HIV‐1 infected children should be considered, and patients may require close clinical monitoring.
Number 4: Advice on Air Travel for Patients with Chronic Respiratory Conditions
Authors: Lien Dale
Published: March 2016

The development of commercial air travel has allowed safe and convenient travel to almost all parts of the world. For patients with chronic respiratory conditions, current proactive attitudes, coupled with advances in drug therapy, oxygen delivery systems and rehabilitation programs, have resulted in many more of us being able to experience the freedom of air travel. When planning for commercial air travel, patients with chronic respiratory disorders must be aware that they are subject to more potential difficulties. However, proper understanding of the problems that may be encountered, coupled with advanced planning and preparation, should minimize any problems.
Respirology Manpower in Canada ‐‐ A Report for the Canadian Thoracic Society Education Committee
Authors: Cockcroft Donald W , Wensley David
Published: March 2016

A report on adult and pediatric respirology manpower in Canada was prepared from data supplied by the Royal College of Physicians and Surgeons of Canada (RCPSC), and from program directors (and other colleagues) at universities across Canada. The data support a significant deficiency of adult respirologists in Canada, which is estimated to be from 10%, based on a 10‐year‐old outdated RCPSC recommendation, to 20%, based on equalization with the ′best′ province, to as high as 50%, based on long waiting lists, particularly for respiratory sleep problems, and estimates obtained from academic centres across Canada. Although there are less data available for pediatric respirology, a similar approach suggests a 50% to 100% shortfall in pediatric respirologists. Output from Canadian training programs in adult and pediatric respirology is not likely to meet this need. We recommend that steps be taken urgently to provide sufficient resources for training adult and pediatric respirologists, and to ensure that funding is provided for subspecialist positions in the community.
Intravenous Sedation for Control of Distress during Lumbar Punctures for Pediatric Cancer Patients
Authors: Ellis Jacqueline , McCarthy Patricia , Gosselin Pierre , Splinter William
Published: March 2016

OBJECTIVE: To compare the sedative and amnestic effects, the rapidity of recovery, and the adverse effects of midazolam and propofol for intravenous sedation. The focus of this paper is the effects of intravenous sedation on distress, the acceptability to parents of this intervention for helping their children cope with painful procedures and the utility of an intravenous sedation program administered by an anesthetist.

PATIENTS AND METHODS: Twenty six children were randomly assigned to intravenous sedation with either midazolam or propofol as the first drug received. Self‐report measures of  anxiety and fear were assessed before and 30 min after the lumbar puncture (LP). Self‐report of pain was also assessed 30 min post‐LP. The children were videotaped during the LP, and the tapes were coded for pain and negative emotion using the Emotion Facial Action Coding System. One parent completed the acceptability questionnaire while the child was in the recovery room.

RESULTS: Only three children indicated pain on the Visual Analogue Scale, and two children had facial expressions indicative of pain during the LP. Fear and anxiety differed as a function of procedure order, and children were more fearful and anxious before the first sedated LP than the second. Intravenous sedation was highly  acceptable to parents, and neither drug was considered superior.

CONCLUSIONS: Intravenous sedation with either propofol or midazolam, in combination with analgesia, was effective for alleviating pain and emotional distress associated with LPs. Although children were told that the sedation would make them relaxed and sleepy, they remained somewhat fearful until they experienced a comfortable LP. The benefits of an anesthetist‐administered intravenous sedation program are discussed.
How Nova Scotia General Practitioners Choose Antibiotics for the Empirical Treatment of Community‐Acquired Pneumonia
Authors: Pendergrast Jacob , Marrie Thomas J
Published: March 2016

OBJECTIVE: To gain an understanding of how physicians in general practice choose antibiotics for the empirical treatment of community‐acquired pneumonia (CAP).

DESIGN: Questionnaire with three sample cases of CAP and a knowledge assessment (mailed to half of the physicians).

POPULATION STUDIED: Nova Scotia family physicians.

RESULTS: One hundred and eighty‐four of the 841 (21.9%) physicians who were mailed a questionnaire responded. A knowledge assessment showed satisfactory knowledge except in two areas ‐ an overestimation of the prevalence of penicillin‐resistant Streptococcus pneumoniae in Nova Scotia and the view that ciprofloxacin was an effective antibiotic for the treatment of CAP (42% of physicians). As the complexity of the case increased, there was decreasing consensus regarding the choice of antibiotic therapy and a decline in prescribing according to guidelines for the treatment of CAP. Also, as the complexity of the cases increased, it became increasingly difficult to discern a decision‐making strategy. For the simplest case ‐ a 17‐year‐old male with presumed Mycoplasma pneumoniae pneumonia ‐ physician factors (age, family practice training), desire to target specific pathogens, and concern with resistance and side effects affected the choice of antibiotic. However, for the most complex case ‐ a 45‐year‐old female with severe pneumonia ‐ familiarity with such a case was the only significant factor and led to treatment with a combination of antibiotics designed to treat both typical and atypical pathogens.

CONCLUSIONS: For uncomplicated cases of CAP, physician factors, desire to treat specific pathogens and concern with resistance affect the choice of antibiotic therapy. For complex cases, familiarity with such cases was the only factor that influenced choice of antibiotic therapy.
Predictors for Multiple Hospital Admissions in Children with Asthma
Authors: Gürkan Fuat , Ece Aydin , Haspolat Kenan , Derman Orhan , Bosnak Mehmet
Published: March 2016

BACKGROUND: Asthma is one of the most frequent causes of preventable hospital admissions among children.

OBJECTIVES: To identify preventable risk factors for future hospital admissions. Some of the environmental and patient characteristics of children who were hospitalized more than once with an acute asthma attack were investigated.

DESIGN, SETTING AND PATIENTS: An analysis was performed of 140 children with asthma, aged three to 15 years, admitted to the Department of Pediatrics at Dicle University Hospital, Diyarbakir, Turkey, over three years, followed for a maximum of 48 months. Associations between hospital admissions and probable predictors (clinical findings, laboratory studies and a detailed case history) were analyzed.

RESULTS: The asthma admissions were higher in boys than in girls (male to female ratio 1.86). Of 140 children, 30 (21.4%) had multiple admissions, defined as a mean of more than one admission per year during the follow‐up period. The following factors were associated significantly with the frequency of hospital admission for asthma attacks when analyzed using a X2 test: indoor cigarette smoking (odds ratio [OR] 2.55), maternal smoking (OR 4.05), symptoms of dermal atopy (OR 2.96), symptoms of allergic conjunctivitis (OR 2.68), age less than five years (OR 5.12) and use of inhaled corticosteroids during the follow‐up (OR 0.37). With multivariate logistic regression analysis, among other factors, only maternal smoking (r=0.29, P=0.017) and age less than five years (r=‐0.32, P=0.012) were significant effective factors for the multiple hospital admissions. No significant association with the frequency of hospital admission was found for sex, serum total immunoglobulin E, history of frequent upper respiratory tract infections or number of family members.

CONCLUSIONS: Prevention of indoor smoking, especially maternal smoking, may be effective in decreasing hospital admissions in children with asthma. Children less than five years of age are more likely to be hospitalized than are children five years of age or greater.
Hospital Room or Treatment Room for Pediatric Inpatient Procedures: Which Location Do Parents and Children Prefer?
Authors: Fanurik Debra , Schmitz Michael L , Reach Kelle , Haynes Katherine , Leatherman Isabel
Published: March 2016

OBJECTIVE: The acute pain management guidelines put forth by the Agency for Health Care Policy and Research recommend that inpatient pediatric procedures be performed in a treatment room rather than in a child′s hospital room. However, hospitals vary widely in their use of treatment rooms for pediatric procedures.  Because there has been little empirical investigation of this clinical issue, the present study explores the preferences of parents and children regarding the performance site of inpatient procedures.

SUBJECTS AND METHODS: One hundred and sixty parents of hospitalized children three to 14 years of age were interviewed about previous experience with medical procedures, procedure site preference (treatment room or hospital room) and reasons for room preference. Children five years of age and older were also asked for their preferences regarding the procedure site.

RESULTS: The hospital room was preferred by the majority of parents and children for minor procedures (blood test, intravenous insertion, bandage change) for reasons consisting primarily of the child′s emotional or physical comfort, convenience and difficulties moving the child due to motor impairment or medical condition. The treatment room was generally selected for more invasive procedures (lumbar punctures, bone marrow aspirations, bladder catheterizations) due to concerns for the privacy of the child and roommate, and the need for special equipment or supplies.

CONCLUSIONS: Results suggest that parents and children may prefer the hospital room or treatment room for a variety of different reasons. More research is needed in this area to develop better guidelines regarding the performance of inpatient pediatric procedures.