Kamran Mahmood

Association of gender with outcomes in critically ill patients

IntroductionThe influence of gender on mortality and other outcomes of critically ill patients is not clear. Different studies have been performed in various settings and patient populations often yielding conflicting results. We wanted to assess the relationship of gender and intensive care unit (ICU) outcomes in the patients included in the Acute Physiology and Chronic Health Evaluation (APACHE) IV database (Cerner Corporation, USA).MethodsWe performed a retrospective review of the data available in the APACHE IV database. A total of 261,255 consecutive patients admitted to adult ICUs in United States from 1 January 2004 to 31 December 2008 were included. Readmissions were excluded from the analysis. The primary objective of the study was to assess the relationship of gender with ICU mortality. The secondary objective was to evaluate the association of gender with active therapy, mechanical ventilation, length of stay in the ICU, readmission rate and hospital mortality. The gender-related outcomes for disease subgroups including acute coronary syndrome, coronary artery bypass graft (CABG) surgery, sepsis, trauma and chronic obstructive pulmonary disease (COPD) exacerbation were assessed as well.ResultsICU mortality was 7.2% for men and 7.9% for women, odds ratio (OR) for death for women was 1.07 (95% confidence interval (CI): 1.04 to 1.1). There was a statistically significant interaction between gender and age. In patients <50 years of age, women had a reduced ICU mortality compared with men, after adjustment for acute physiology score, ethnicity, co-morbid conditions, pre-ICU length of stay, pre-ICU location and hospital teaching status (adjusted OR 0.83, 95% CI: 0.76 to 0.91). But among patients ≥50 years of age, there was no significant difference in ICU mortality between men and women (adjusted OR 1.02, 95% CI: 0.98 to 1.06).A higher proportion of men received mechanical ventilation, emergent surgery, thrombolytic therapy and CABG surgery. Men had a higher readmission rate and longer length of ICU stay. The adjusted mortality of women compared to men was higher with CABG, while it was lower with COPD exacerbation. There was no significant difference in mortality in acute coronary syndrome, sepsis and trauma.ConclusionsAmong the critically ill patients, women less than 50 years of age had a lower ICU mortality compared to men, while 50 years of age or older women did not have a significant difference compared to men. Women had a higher mortality compared to men after CABG surgery and lower mortality with COPD exacerbation. There was no difference in mortality in acute coronary syndrome, sepsis or trauma.

Learning Experience of Linear Endobronchial Ultrasound Among Pulmonary Trainees

BACKGROUND Linear endobronchial ultrasound (EBUS) allows real-time guidance of transbronchial needle aspiration of thoracic structures and has become an increasingly important diagnostic tool for chest physicians. Little has been published about the learning experience of operators with this technology. The purpose of this study was to define the learning experience of EBUS-guided transbronchial needle aspiration (EBUS-TBNA) among pulmonary trainees. METHODS This was a multicenter cohort study of fellows in pulmonary medicine over the first 2 years of their training. Prior to performing EBUS-TBNA, all participants had to complete 30 conventional bronchoscopies, an EBUS-specific didactic curriculum, and a simulation session with a plastic airway model. Each consecutive EBUS procedure was scored with a checklist that evaluated the ability to pass a bronchoscope through vocal cords, identify the appropriate node for sampling, acquire adequate ultrasound images, guide the bronchoscopy team through the technical steps of EBUS-TBNA, and obtain adequate tissue samples. RESULTS Thirteen pulmonary trainees from three training programs were enrolled in the study and were observed over a 2-year period. The majority of trainees were able to perform all essential steps of EBUS-TBNA and obtain adequate tissue after performing an average of 13 (95% CI, 7-16) procedures. CONCLUSIONS Pulmonary trainees needed an average of 13 procedures to achieve first independent successful performance of EBUS-TBNA following a training protocol that included a didactic curriculum and simulation-based practice. Our findings could guide pulmonary fellowship directors in planning EBUS training and establishing a reasonable juncture to assess EBUS skills with validated assessment tools.

Randomized Trial of Pleural Fluid Drainage Frequency in Patients with Malignant Pleural Effusions. The ASAP Trial

Rationale: Patients with malignant pleural effusions have significant dyspnea and shortened life expectancy. Indwelling pleural catheters allow patients to drain pleural fluid at home and can lead to autopleurodesis. The optimal drainage frequency to achieve autopleurodesis and freedom from catheter has not been determined. Objectives: To determine whether an aggressive daily drainage strategy is superior to the current standard every other day drainage of pleural fluid in achieving autopleurodesis. Methods: Patients were randomized to either an aggressive drainage (daily drainage; n = 73) or standard drainage (every other day drainage; n = 76) of pleural fluid via a tunneled pleural catheter. Measurements and Main Results: The primary outcome was the incidence of autopleurodesis following the placement of the indwelling pleural catheters. The rate of autopleurodesis, defined as complete or partial response based on symptomatic and radiographic changes, was greater in the aggressive drainage arm than the standard drainage arm (47% vs. 24%, respectively; P = 0.003). Median time to autopleurodesis was shorter in the aggressive arm (54 d; 95% confidence interval, 34‐83) as compared with the standard arm (90 d; 95% confidence interval, 70 to nonestimable). Rate of adverse events, quality of life, and patient satisfaction were not significantly different between the two arms. Conclusions: Among patients with malignant pleural effusion, daily drainage of pleural fluid via an indwelling pleural catheter led to a higher rate of autopleurodesis and faster time to liberty from catheter. Clinical trial registered with www.clinicaltrials.gov (NCT 00978939).

Ventilation and Anesthetic Approaches for Rigid Bronchoscopy

Due to growing interest in management of central airway obstruction, rigid bronchoscopy is undergoing a resurgence in popularity among pulmonologists. Performing rigid bronchoscopy requires use of deep sedation or general anesthesia to achieve adequate patient comfort, whereas maintaining oxygenation and ventilation via an uncuffed and often open rigid bronchoscope requires use of ventilation strategies that may be unfamiliar to most pulmonologists. Available approaches include apneic oxygenation, spontaneous assisted ventilation, controlled ventilation, manual jet, and high-frequency jet ventilation. Anesthetic technique is partially dictated by the selected ventilation strategy but most often relies on a total intravenous anesthetic approach using ultra-short-acting sedatives and hypnotics for a rapid offset of action in this patient population with underlying respiratory compromise. Gas anesthetic may be used with the rigid bronchoscope, minimizing leaks with fenestrated caps placed over the ports, although persistent circuit leaks can make this approach challenging. Jet ventilation, the most commonly used ventilatory approach, may be delivered manually using a Sanders valve or via an automated ventilator at supraphysiologic respiratory rates, allowing for an open rigid bronchoscope to facilitate ease of moving tools in and out of the airway. Despite a patient population that often suffers from significant respiratory compromise, major complications with rigid bronchoscopy are uncommon and are similar among modern ventilation approaches. Choice of ventilation technique should be determined by local expertise and equipment availability. Appropriate patient selection and recognition of limitations associated with a given ventilation strategy are critical to avoid procedural-related complications.

Therapeutic bronchoscopy improves spirometry, quality of life, and survival in central airway obstruction

Background: Central airway obstruction (CAO) occurs in patients with primary or metastatic lung malignancy and nonmalignant pulmonary disorders and results in significant adverse effects on respiratory function and quality of life. Objectives: The objective of this study was to assess the effect of therapeutic bronchoscopic interventions on spirometry, dyspnea, quality of life, and survival in patients with CAO. Methods: We prospectively studied patients who underwent therapeutic rigid bronchoscopy for CAO. Spirometry, San Diego Shortness of Breath questionnaire (SOBQ), and SF-36 questionnaire responses were obtained before the procedure and at follow-up 6-8 weeks after the procedure. Results: Fifty-three patients (24 malignant and 29 nonmalignant CAO), who underwent successful rigid bronchoscopic intervention, were enrolled. Airway stent placement and various debulking techniques including mechanical debridement and heat therapy were used. After bronchoscopy, there was a significant increase in forced vital capacity (2.2 ± 0.91 l before, 2.7 ± 0.80 l after, p = 0.009) and forced expiratory volume at 1 s (1.4 ± 0.60 l before, 1.8 ± 0.67 l after, p = 0.002). The SOBQ score improved from 55.8 ± 30.1 before the procedure to 37.9 ± 27.25 after the procedure (p = 0.002). In the SF-36, there was an improvement in almost all domains, with statistically significant improvement seen in several domains. Benefits were seen independent of the etiology of CAO, site of intervention or stent placement. The patients with malignant CAO, in whom airway patency could not be achieved, had a poor survival. Conclusions: Alleviation of CAO with therapeutic rigid bronchoscopy results in improvement in spirometry, shortness of breath, quality of life, and survival.

Treatment of infection associated with tunneled pleural catheters.

Chronic indwelling tunneled pleural catheters are increasingly used for the treatment of malignant pleural effusions. Some common complications of these catheters include empyema and local site infection. Empyema is generally treated with the removal of the pleural catheter and the administration of systemic antibiotics. We propose a different and more conservative but effective method of the treatment of infected tunneled pleural catheters.

Ablative therapies for central airway obstruction.

Central airway obstruction (CAO) is seen in malignant and nonmalignant airway disorders and can lead to significant morbidity and mortality. Endobronchial ablative therapies are used in conjunction with mechanical debridement to achieve hemostasis and restore airway patency. These therapies can be classified into modalities with immediate or delayed effect. Therapies with immediate effect include heat therapies (such as electrocautery, argon plasma coagulation, and laser) and cryorecanalization using a cryoprobe for tissue extraction. These modalities can be used in severe CAO for immediate relief of obstruction. Therapies with delayed effect include cryotherapy, brachytherapy, and photodynamic therapy. These modalities should not be used for acutely symptomatic CAO, and typically require follow-up bronchoscopy for removal of debris from the airway. Multimodality approach typically leads to better outcomes.

Hemorrhagic Complications of Thoracentesis and Small-Bore Chest Tube Placement in Patients Taking Clopidogrel

RATIONALE Clopidogrel is a commonly used antiplatelet medication. The risk of local hemorrhage associated with use of this drug during routine thoracentesis or small-bore chest tube placement is not well established. OBJECTIVES We conducted a prospective cohort study to assess the risk of hemothorax in patients taking clopidogrel while undergoing either pleural procedure. METHODS Twenty-five consecutive adult patients who were taking clopidogrel at the time they were offered thoracentesis or small-bore (14 Fr) chest tube placement consented to continue taking the drug through their procedure. A control group consisted of 50 patients undergoing these pleural procedures who were not taking clopidogrel at the time they consented to undergo either procedure. All of the pleural procedures were performed under ultrasound guidance by an interventional pulmonologist or a fellow under direct faculty supervision. Hospitalized patients were screened for hemothorax by observing for a post-procedure drop in blood hemoglobin content of 2 g/dl or reaccumulation of their pleural effusion within 24 hours of the procedure. Outpatients were called within 2 weeks after their procedure to determine whether they had any symptoms suggestive of hemothorax. MEASUREMENTS AND MAIN RESULTS There was one case of hemothorax after thoracentesis in the clopidogrel group versus none in the control group. The one patient with hemothorax required transfusion with 2 units of packed red blood cells and small-bore chest tube placement, and clopidogrel was withheld. There were no other clinically apparent complications of either procedure. CONCLUSIONS Considered in combination with other small previously published studies, this single-center, nonrandomized, controlled prospective cohort study suggests that the rate of clinically consequential hemorrhage after ultrasound-guided thoracentesis or chest tube placement in patients taking clopidogrel is sufficiently low to warrant a large, randomized clinical trial designed to determine the safety of performing these procedures without interrupting clopidogrel therapy.

Hypoxic Gene Expression of Donor Bronchi Linked to Airway Complications after Lung Transplantation

RATIONALE Central airway stenosis (CAS) after lung transplantation has been attributed in part to chronic airway ischemia; however, little is known about the time course or significance of large airway hypoxia early after transplantation. OBJECTIVES To evaluate large airway oxygenation and hypoxic gene expression during the first month after lung transplantation and their relation to airway complications. METHODS Subjects who underwent lung transplantation underwent endobronchial tissue oximetry of native and donor bronchi at 0, 3, and 30 days after transplantation (n = 11) and/or endobronchial biopsies (n = 14) at 30 days for real-time polymerase chain reaction of hypoxia-inducible genes. Patients were monitored for 6 months for the development of transplant-related complications. MEASUREMENTS AND MAIN RESULTS Compared with native endobronchial tissues, donor tissue oxygen saturations (Sto2) were reduced in the upper lobes (74.1 ± 1.8% vs. 68.8 ± 1.7%; P < 0.05) and lower lobes (75.6 ± 1.6% vs. 71.5 ± 1.8%; P = 0.065) at 30 days post-transplantation. Donor upper lobe and subcarina Sto2 levels were also lower than the main carina (difference of -3.9 ± 1.5 and -4.8 ± 2.1, respectively; P < 0.05) at 30 days. Up-regulation of hypoxia-inducible genes VEGFA, FLT1, VEGFC, HMOX1, and TIE2 was significant in donor airways relative to native airways (all P < 0.05). VEGFA, KDR, and HMOX1 were associated with prolonged respiratory failure, prolonged hospitalization, extensive airway necrosis, and CAS (P < 0.05). CONCLUSIONS These findings implicate donor bronchial hypoxia as a driving factor for post-transplantation airway complications. Strategies to improve airway oxygenation, such as bronchial artery re-anastomosis and hyperbaric oxygen therapy merit clinical investigation.

The Changing Role for Tracheostomy in Patients Requiring Mechanical Ventilation

Tracheostomy is performed in patients who require prolonged mechanical ventilation or have upper airway instability. Percutaneous tracheostomy with Ciaglia technique is commonly used and rivals the surgical approach. Percutaneous technique is associated with decreased risk of stomal inflammation, infection, and bleeding along with reduction in health resource utilization when performed at bedside. Bronchoscopy and ultrasound guidance improve the safety of percutaneous tracheostomy. Early tracheostomy decreases the need for sedation and intensive care unit stay but may be unnecessary in some patients who can be extubated later successfully. A multidisciplinary approach to tracheostomy care leads to improved outcomes.