Respiratory System Commons^™

Post-Mortem Investigation Of Deaths Due To Pneumonia In Children Aged 1–59 Months In Sub-Saharan Africa And South Asia From 2016 To 2022: An Observational Study., Sana Mahtab, Dianna Blau, Zachary Madewell, Ikechukwu Ogbuanu, Julius Ojulong, Sandra Lako, Hailemariam Legesse, Joseph Bangura, Quique Bassat, Gunturu Revathi

Pathology, East Africa

Background; The Child Health and Mortality Prevention Surveillance (CHAMPS) Network programme undertakes post-mortem minimally invasive tissue sampling (MITS), together with collection of ante-mortem clinical information, to investigate causes of childhood deaths across multiple countries. We aimed to evaluate the overall contribution of pneumonia in the causal pathway to death and the causative pathogens of fatal pneumonia in children aged 1–59 months enrolled in the CHAMPS Network.

Methods; In this observational study we analysed deaths occurring between Dec 16, 2016, and Dec 31, 2022, in the CHAMPS Network across six countries in sub-Saharan Africa (Ethiopia, Kenya, Mali, Mozambique, Sierra Leone, and …

Community-Based Asthma Assessment In Young Children: Adaptations For A Multicentre Longitudinal Study In South Asia, Mohammad Shahidul Islam, Samin Huq, Steven Cunningham, Jurgen Schwarze, Asmd Ashraful Islam, Mashal Amin, Farrukh Raza, Benazir Baloch, Muhammad Imran Nisar, Sajid Bashir Soofi

Department of Paediatrics and Child Health

Background: Systematic assessment of childhood asthma is challenging in low- and middle-income country (LMIC) settings due to the lack of standardised and validated methodologies. We describe the contextual challenges and adaptation strategies in the implementation of a community-based asthma assessment in four resource-constrained settings in Bangladesh, India, and Pakistan.
Method: We followed a group of children of age 6-8 years for 12 months to record their respiratory health outcomes. The study participants were enrolled at four study sites of the 'Aetiology of Neonatal Infection in South Asia (ANISA)' study. We standardised the research methods for the sites, trained field staff …

Outcomes Of Covid-19 Infection In Patients With Hematological Malignancies- A Multicenter Analysis From Pakistan, Adeeba Zaki, Salman Muhammad Soomar, Danish Hasan Khan, Hasan Shaharyar Sheikh, Raheel Iftikhar, Ayaz Mir, Zeba Aziz, Khadija Bano, Hafsa Naseer, Qamar Un-Nisa Chaudhry

Section of Haematology/Oncology

Purpose: COVID-19 infection resulting from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) began to spread across the globe in early 2020. Patients with hematologic malignancies are supposed to have an increased risk of mortality from coronavirus disease of 2019 (COVID-19) infection. From Pakistan, we report the analysis of the outcome and interaction between patient demographics and tumor subtype and COVID-19 infection and hematological malignancy.
Patients and methods: This multicenter, retrospective study included adult patients with a history of histologically proven hematological malignancies who were tested positive for COVID-19 via PCR presented at the oncology department of 5 tertiary care hospitals …

Healthcare Simulation: A Key To The Future Of Medical Education - A Review, Omair Ayaz, Faisal Wasim Ismail

Medical College Documents

Aim: Simulation originates from its application in the military and aviation. It is implemented at various levels of healthcare education and certification today. However, its use remains unevenly distributed across the globe due to misconception regarding its cost and complexity and to lack of evidence for its consistency and validity. Implementation may also be hindered by an array of factors unique to the locale and its norms. Resource-poor settings may benefit from diverting external funds for short-term simulation projects towards collaboration with local experts and local material sourcing to reduce the overall cost and achieve long-term benefits. The recent shift …

The Who Global Tuberculosis 2021 Report - Not So Good News And Turning The Tide Back To End Tb, Chakaya Jeremiah, Eskild Petersen, Rebecca Nantanda, Brenda N. Mungai, Giovanni Battista Migliori, Farhana Amanullah, Patrick Lungu, Francine Ntoumi, Nagalingeswaran Kumarasamy

Department of Paediatrics and Child Health

Objective: To review the data presented in the 2021 WHO global TB report and discuss the current constraints in the global response.
Introduction and methods: The WHO global TB reports, consolidate TB data from countries and provide up to date assessment of the global TB epidemic. We reviewed the data presented in the 2021 report.
Results: We noted that the 2021 WHO global TB report presents a rather grim picture on the trajectory of the global epidemic of TB including a stagnation in the annual decline in TB incidence, a decline in TB notifications and an increase in estimated TB …

Pulmonary Adenoid Cystic Carcinoma Presenting Late With Intrapericardial Extension: Case Report, Manzar Abbas, Usama Qamar, Syeda Maria Ahmad Zaidi, Faiqa Binte Aamir, Ali Aahil Noorali, Haseeb Ur Rahman, Saulat Hasnain Fatimi

Medical College Documents

Adenoid cystic carcinoma, also known as cylindroma, is one of the rare and unexplored clinical presentations of lung cancer, for which existing knowledge is scarce. This case report discusses a presentation of this tumor in the right lung, which subsequently extended to the left atrium through the right superior pulmonary vein. The extension of this rare tumor into the left atrium makes this case both uniquely distinctive and clinically relevant. The management strategy opted for this case was a right posterolateral thoracotomy and right pneumonectomy with partial resection of the left atrium. The desired outcome of this report is to …

Risk Factors For Acute Respiratory Infections In Children Between 0 And 23 Months Of Age In A Peri-Urban District In Pakistan: A Matched Case–Control Study, Fatima Mir, Shabina Ariff, Maria Asif Bhura, Suhail Chanar, Aspara Ali, Muhammad Jawwad, A Hussain, Arjumand Rizvi, Muhammad Umer, Zahid Memon, Atif Habib, Sajid Bashir Soofi, Zulfiqar Ahmed Bhutta

Department of Paediatrics and Child Health

Background: Acute respiratory infection (ARI) accounts for nearly 15% of all childhood mortality in South Asia, with children from rural areas at higher risk due to inaccessibility to healthcare facilities. We therefore aimed to identify risk factors associated with ARI in children under 2 years of age in rural Pakistan.
Methods: A retrospective 1:2 matched case-control study was conducted between October and December 2018 in Taluka Kotri, Jamshoro District of Pakistan. Cases were identified as children between 0 and 23 months of age with a history of fever, cough, sore throat, fast breathing, difficulty breathing, or chest indrawing in the …

Mobile Critical Care Recovery Program (M-Ccrp) For Acute Respiratory Failure Survivors: Study Protocol For A Randomized Controlled Trial, Sikandar Khan, Ashok Biju, Sophia Wang, Sujuan Gao, Omar Irfan, Amanda Harrawood, Stephanie Martinez, Anthony Perkins, Frederick W. Unverzagt, Sue Lasiter

Medical College Documents

Background: Patients admitted to intensive care units (ICU) with acute respiratory failure (ARF) face chronic complications that can impede return to normal daily function. A mobile, collaborative critical care model may enhance the recovery of ARF survivors.
Methods: The Mobile Critical Care Recovery Program (m-CCRP) study is a two arm, randomized clinical trial. We will randomize 620 patients admitted to the ICU with acute respiratory failure requiring mechanical ventilation in a 1:1 ratio to one of two arms (310 patients per arm) – m-CCRP intervention versus attention control. Those in the intervention group will meet with a care coordinator after …

Children’S Oxygen Administration Strategies Trial (Coast): A Randomised Controlled Trial Of High Flow Versus Oxygen Versus Control In African Children With Severe Pneumonia., Kathryn Maitland, Sarah Kiguli, Robert Opoka, Peter Olupot-Olupot, Charles Engoru, Patricia Njuguna, Victor Bandika, Ayub Mpoya, Andrew Bush, Thomas Williams

Paediatrics and Child Health, East Africa

Background: In Africa, the clinical syndrome of pneumonia remains the leading cause of morbidity and mortality in children in the post-neonatal period. This represents a significant burden on in-patient services. The targeted use of oxygen and simple, non-invasive methods of respiratory support may be a highly cost-effective means of improving outcome, but the optimal oxygen saturation threshold that results in benefit and the best strategy for delivery are yet to be tested in adequately powered randomised controlled trials. There is, however, an accumulating literature about the harms of oxygen therapy across a range of acute and emergency situations that have …

Global Respiratory Syncytial Virus-Associated Mortality In Young Children (Rsv Gold): A Retrospective Case Series, Nienke M. Scheltema, Angela Gentile, Florencia Lucion, D James Nokes, Patrick K. Munywoki, Shabir A. Madhi, Michelle J. Groome, Cheryl Cohen, Jocelyn Moyes, Syed Asad Ali

Department of Paediatrics and Child Health

Background: Respiratory syncytial virus (RSV) infection is an important cause of pneumonia mortality in young children. However, clinical data for fatal RSV infection are scarce. We aimed to identify clinical and socioeconomic characteristics of children aged younger than 5 years with RSV-related mortality using individual patient data.

Methods: In this retrospective case series, we developed an online questionnaire to obtain individual patient data for clinical and socioeconomic characteristics of children aged younger than 5 years who died with community-acquired RSV infection between Jan 1, 1995, and Oct 31, 2015, through leading research groups for child pneumonia identified through a comprehensive …

Atrial Thrombus In A Premature Newborn Following Cardio-Pulmonary Resuscitation, Syed Rehan Ali, Shakeel Ahmed, Nadeem Aslam, Heeramani Lohana

Department of Paediatrics and Child Health

Critically ill newborns, whether term or preterm, are at great risk for developing symptomatic thromboembolic disease. Comorbidities like inflammation, DIC, fluctuations in cardiac output, congenital heart disease, as well as central venous or arterial catheters, are the predisposing risk factors. Clinically symptomatic or asymptomatic cases are usually picked up by echocardiography, usually done for other indications. Management usually comprises of observation, heparin therapy, thrombo-embolectomy, and catheter directed revascularization. We present a case of premature neonate who developed thrombus at inter-atrial septum as a possible consequence of cardiopulmonary resuscitation, detected by echocardiography. Conversely, there is always a possibility of paradoxical emboli …

Right-Sided Congenital Diaphragmatic Hernia And Myelomeningocele: A Rare Association, Syed Rehan Ali, Shakeel Ahmed

Department of Paediatrics and Child Health

Congenital diaphragmatic hernia (CDH) is a rare birth defect with a prevalence of < 0.5 per 1,000 live births. Majority of these defects are left-sided as most studies suggest that frequency of right-sided CDH was 10% of the total. The association of CDH with myelomeningocele (MMC) is extremely rare; as in Sweed's study of 116 consecutive cases of CDH, the incidence of associated MMC with CDH was stated as 4.3%. There has been one previous case report of leftsided CDH, MMC and hydrocephalus prenatally diagnosed; but to the best of authors' knowledge, this is the first reported case of the above constellation with a right-sided CDH diagnosed prenatally.

Vascular Ehlers-Danlos Syndrome: A Rare Disorder Presenting With Focal Convulsions, Shakeel Ahmed, Syed Rehan Ali, Naila Nadeem, Muhammad Hamid

Department of Paediatrics and Child Health

Vascular Ehlers-Danlos Syndrome (VEDS), previously called Ehlers-Danlos syndrome type-IV, is a heterogeneous group of heritable connective tissue disorders characterized by thin, translucent skin, easy bruising, arterial, intestinal, and/or uterine fragility. There is large vessel involvement that leads to arterial rupture often preceded by aneurysm, arteriovenous fistulae, or dissection. Noninvasive imaging studies such as CT angiography and MR angiography are preferred as diagnostic studies for this condition. We are reporting a 4 years old girl who was presented with right sided unilateral convulsions and hypertension. CT angiogram showed stenosis with post-stenotic dilatation of coeliac and superior mesenteric arteries. There were extensive …

Early Recovery In Post Varicella Transverse Myelitis, Prem Chand, Shahnaz Brahim, Syed Sohail Zaidi, Nida Amjad

Department of Paediatrics and Child Health

A two and a half year old Kenyan girl presented with recurrent chest infections and difficulty in swallowing. Her clinical and laboratory workup was suggestive of lower respiratory tract infection for which she received a course of antibiotics; however, she remains symptomatic after the management of her suspected diagnosis. Therefore, further radiological workup including a chest CT scan and barium study were performed. This showed a homogeneous mass surrounded by ascending and descending aorta in the posterior mediastinum that was compressing the middle esophagus. She had a posterolateral thoracotomy which revealed a cystic mass with smooth surfaces (5 x 5 …

Posterior Mediastinal Branchial Cleft Cyst: An Unusual Site, Abdul Rashid, Vaqas Ahmad, Saqib Qazi, Abdul Gaffar Billoo, Sajida Rashid, Ali Faisal Saleem

Department of Paediatrics and Child Health

A two and a half year old Kenyan girl presented with recurrent chest infections and difficulty in swallowing. Her clinical and laboratory workup was suggestive of lower respiratory tract infection for which she received a course of antibiotics; however, she remains symptomatic after the management of her suspected diagnosis. Therefore, further radiological workup including a chest CT scan and barium study were performed. This showed a homogeneous mass surrounded by ascending and descending aorta in the posterior mediastinum that was compressing the middle esophagus. She had a posterolateral thoracotomy which revealed a cystic mass with smooth surfaces (5x5 cm) in …

A Double Blind Community-Based Randomized Trial Of Amoxicillin Versus Placebo For Fast Breathing Pneumonia In Children Aged 2-59 Months In Karachi, Pakistan (Retapp), Fyezah Jehan, Muhammad Imran Nisar, Salima Kerai, Nick Brown, Benazir Balouch, Zulfiqar Hyder, Gwen Ambler, Amy Sarah Ginsburg, Anita K. M. Zaidi

Department of Paediatrics and Child Health

Background: Fast breathing pneumonia is characterized by tachypnoea in the absence of danger signs and is mostly viral in etiology. Current guidelines recommend antibiotic therapy for all children with fast breathing pneumonia in resource limited settings, presuming that most pneumonia is bacterial. High quality clinical trial evidence to challenge or support the continued use of antibiotics, as recommended by the World Health Organization is lacking.

Methods/Design: This is a randomized double blinded placebo-controlled non-inferiority trial using parallel assignment with 1:1 allocation ratio, to be conducted in low income squatter settlements of urban Karachi, Pakistan. Children 2-59 months old with fast …

Over Prescription Of Antibiotics For Adult Pharyngitis Is Prevalent In Developing Countries But Can Be Reduced Using Mcisaac Modification Of Centor Scores: A Cross-Sectional Study., Amber Hanif Palla, Rafeeq Alam Khan, Anwar H. Gilani, Fawziah Marra

Department of Biological & Biomedical Sciences

Background

Although Group A beta hemolytic streptococcus (GABHS) can cause bacterial pharyngitis, the most common etiology is viral; despite this viral etiology, antibiotics are commonly prescribed for this infection in industrialized countries. We investigated the prevalence of GABHS in adult pharyngitis patients from lower socioeconomic settings in Karachi, Pakistan, how often antibiotics are prescribed for pharyngitis and if appropriate agents were used in a developing world setting. Finally, we wanted to see the usefulness of modified McIsaac scores in predicting positive cultures.

Methods

Adult patients were recruited from three local hospital outpatient dispensaries (OPDs). All patients aged 14–65 years who …

Assessing Two Spirometric Criteria Of Pre-Bronchodilator And Post-Bronchodilator Fev1/Fvc Ratio In Detecting Air Flow Obstruction, Zeeshan Waheed, Muhammad Irfan, Ahmed Suleman Haque, Najmul Hasan Siddiqui, Safia Awan, Beenish Syed, Javaid Khan

Section of Pulmonary & Critical Care

OBJECTIVES: To assess the Pre-bronchodilator criteria and the Post-bronchodilator criteria of FEV1/FVC ratio in diagnosing Airflow obstruction.

METHODS: An observational study was conducted from 1988 to 2006 at the Aga Khan University Hospital Patients referred to the pulmonary function test laboratory for spirometry with bronchodilator reversibility at the hospital during the above said period were enrolled. Forced spirometry was performed according to ATS guidelines. All patients who had pre-bronchodilator criteria of airflow obstruction were analyzed and compared with the post bronchodilator criteria.

RESULTS: A total of 4222 individuals underwent spirometry out of which 4072 individuals were studied. Using the pre …

Hughes-Stovin Syndrome, Umair Khalid, Taimur Saleem

Section of Pulmonary & Critical Care

Hughes-Stovin Syndrome (HSS) is a very rare clinical disorder characterized by thrombophlebitis and multiple pulmonary and/or bronchial aneurysms. Less than 40 published cases of HSS have been described in English medical literature so far. The exact etiology and pathogenesis of HSS is unknown, possible causes include infections and angiodysplasia. HSS has also been considered as a variant of Behcet's disease (BD). Patients with HSS usually present with cough, dyspnea, fever, chest pain and haemoptysis. The management of HSS can either be medical or surgical. Medical management includes the use of steroids and cytotoxic agents. Cyclophosphamide, in particular, is a favored …

Negative Pressure Pulmonary Oedema: A Rare Complication Following General Anaesthesia, Zeeshan Waheed, Javaid Khan

Section of Pulmonary & Critical Care

An important cause of pulmonary oedema is Negative Pressure Pulmonary Oedema (NPPE) which characteristically develops soon after extubation from an endo-tracheal intubation. In this case report we identified a case of previously healthy man who was intubated for General Anaesthesia for extraction of impacted molar tooth. Soon after extubation he developed severe respiratory distress. Immediate diagnosis of NPPE secondary to post extubation laryngospasm was made. He was promptly treated with 100 percent oxygen via CPAP (continuous positive airway pressure) mask and within an hour he markedly improved and subsequently became asymptomatic. NPPE is an important cause of morbidity and need …

Cerebral Salt Wasting Syndrome In Tuberculous Meningitis, Abdul Jabbar, Syed Nadir Farrukh, Rabbia Khan

Section of Internal Medicine

Case of a seventy year old female, who developed cerebral salt wasting syndrome in association with Tuberculous Meningitis is presented.

Variables Predictive Of Outcome In Patients With Acute Hypercapneic Respiratory Failure Treated With Noninvasive Ventilatio, Nawal Salahuddin, Muhammad Irfan, Shereen Khan, Muhammad Naeem, Ahmad Suleman Haque, Shahid Javed Husain, Nisar Ahmed Rao, Ali Bin Sarwar Zubairi, Javaid Khan

Section of Pulmonary & Critical Care

OBJECTIVE: To assess results with NIV in acute hypercapneic respiratory failure and to identify outcome predictors.

METHODS: This was a retrospective observational study on consecutive patients presenting with acute type II respiratory failure and meeting criteria for NIV use over a 5 year period. Patients presenting with haemodynamic instability, inability to protect their airway, malignant arrhythmias and recent oesophageal surgery were excluded. Univariate and Multivariate regression analysis was used to determine the impact on survival. A p value of < 0.05 was considered statistically significant. Software used was SPSS 14.

RESULTS: Total numbers of patients included were 119; 52.9% were males. Mean age was 63.4 +/- 11.9 years. Overall Survival to …

Wegener's Granulomatosis: A Diagnostic Challenge, Ali Bin Sarwar Zubairi, Hammad Bin Liaquat, Shahid Javed Husain, Kulsoom Fatima

Section of Pulmonary & Critical Care

Wegener's Granulomatosis (WG) is a necrotizing granulomatous vasculitis that primarily involves small vessels in the body. Patient usually presents in the fourth to fifth decade. The clinical presentation is variable; however, majority of patients (90%) seek medical attention for nasal and sinus symptoms with or without lower respiratory symptoms of cough, dyspnoea and haemoptysis. The typical form of WG tends to involve the triad of upper and lower respiratory tract and the kidneys; while involvement of other organs like ocular, cutaneous, rheumatological, neural, gastrointestinal and lower genito-urinary tract is occasionally seen. A "limited" form with clinical findings isolated to the …

Treatment Outcome Of Multi-Drug Resistant Tuberculosis In A Tertiary Care Hospital In Karachi, Nisar Ahmed Rao, Zeeshan Mahfooz, Muhammad Irfan

Section of Pulmonary & Critical Care

Objective: To assess the outcomes of pulmonary multidrug-resistant tuberculosis (MDR-TB) patients treated at Ojha Institute of Chest Diseases (OICD), a reference hospital for TB in Karachi, Pakistan. Methods: Clinical study for the period 1996-2006, with follow-up until June 2007 was performed. All the culture and sensitivity proven cases of MDR pulmonary TB were initially admitted for 3-6 months till the sputum converted negative. Treatment regimen was decided on individual basis, and included 4-6 drugs. Supervised treatment was given to all patients during the hospitalization. After discharge from the hospital, patients were followed at monthly interval at the outpatient department of …

Community Acquired Pneumonia: Risk Factors Associated With Mortality In A Tertiary Care Hospitalized Patients, Muhammad Irfan, Syed Fayyaz Hussain, Khubaib Mapara, Shafia Memon, Mohammed Mogri, Muniza Bana, Amna Malik, Sara Khan, Nadia A Khan

Section of Pulmonary & Critical Care

OBJECTIVE: To evaluate risk factors associated with mortality in patients hospitalized with CommunityAcquired Pneumonia (CAP) from a developing country.

METHODS: An observational study was conducted on adult patients admitted with a diagnosis of CAP from January 2002 to August 2003 at Aga Khan University hospital, Karachi, Pakistan. Clinical records were reviewed for demographic characteristics, clinical and laboratory features, hospital course, and risk factors associated with mortality.

RESULTS: A total of 329 patients (187 males) were admitted with CAP. Two-third of patients had underlying co-morbid medical illnesses. Complications developed in 15.7% cases and the overall mortality rate was 11%. Risk factors …

Clinical Characteristics, Management And Outcome Of Major Pulmonary Embolism: An Experience From A Tertiary Care Center In Pakistan, Shahid Javed Husain, Ali Bin Sarwar Zubairi, Kulsoom Fatima, Muhammad Irfan, Muhammad Atif, Muhammad Ammad Saeed

Section of Pulmonary & Critical Care

OBJECTIVE: To evaluate the clinical characteristics, risk factors, management and outcome of major pulmonary embolism (PE) in a tertiary care center of Karachi.

METHODS: Medical records of all patients who underwent a spiral CT scan of the chest for suspected pulmonary embolism were reviewed between January 2000 and June 2007 at the Aga Khan University Hospital, Karachi. Patients having evidence of major pulmonary embolism on spiral CT scan were selected.

RESULTS: A total of 30 patients (10 males, 20 females) with mean age 52 +/- 14.59 years were identified who fulfilled our predefined criteria for major pulmonary embolism. Risk factors …

Assessment Of Asthma Control Using The Asthma Control Test At A Tertiary Care Centre In Karachi, Pakistan, Sana Shoukat, Saqib Ali Gowani, Ameer Ali Khowaja, Javaid Khan

Section of Pulmonary & Critical Care

The aim of our study was to assess asthma control among asthmatics at a tertiary care setting in Karachi using ACT questionnaire. The ACT questionnaire was filled by known asthmatics in January 2007. A total of 150 questionnaires were filled of which, 61 (40%) were males and 89 (60%) females. Mean ACT score was 17.71 +/- 4.41. Association between sex and asthma control was not statistically significant. Significant association was seen with asthma control and Ipratropium bromide inhaler. Asthma control among patients at a tertiary care centre is moderate. ACT can be used to follow patients in the hospital.

Airway Management In A Patient With Huge Neck Mass, Anwarul Huda, Mohammad Hamid

Department of Anaesthesia

Airway management of patient with huge neck swelling is always challenging for the anaesthetist. We describe successful management of a patient who presented in our ER with stridor as a result of massively enlarged thyroid gland. Varieties of options are available for appropriate airway management in such cases which are discussed.

Primary Drug Resistance Against Mycobacterium Tuberculosis In Karachi, Nisar Ahmed Rao, Muhammad Irfan, Shahid Javed Hussain

Section of Pulmonary & Critical Care

OBJECTIVE: To evaluate the primary drug resistance of new culture positive cases of pulmonary tuberculosis in Karachi.

METHODS: All new suspected pulmonary tuberculosis patients were recruited initially. They were instructed to produce three-sputum samples for smear examination and on one of the specimen's culture was applied. Bronchoscopy and bronchial wash was done in patients who were not expectorating. Bronchial wash was then applied for both smear and culture for Mycobacterium tuberculosis.

RESULTS: Out of 79 cases recruited initially, 52 were able to produce sputum while bronchoscopy was performed in the remaining. AFB direct smear was positive in 32/52 sputum and …

Socio-Demographic Correlates Of Exhaled Breath Carbon Monoxide In Karachi's Adult Population, Majid Shafiq, Sumera Khan, M. Rizwanulhaq Khawaja, Suleman Haque, Javaid Khan

Section of Pulmonary & Critical Care

OBJECTIVE: To examine the relationship between CO levels and putative factors including smoking status among residents of Karachi, an urban center with very high levels of air pollution.

METHODS: Two hundred and eighteen volunteering subjects were asked to maximally exhale into a Smokerlyzer breath CO analyzer. Each of the volunteers was also asked to reply to a questionnaire-based interview seeking demographic information as well as details of exposure to tobacco, traffic fumes and other air pollutants.

RESULTS: Out of the 218 participating subjects, 75% were males and 27% were current or ex-smokers. The mean CO level was 2.92 parts per …