Joseph D. Zibrak

Indications for Pulmonary Function Testing

STUDY OBJECTIVE To critically assess original studies evaluating the role of preoperative pulmonary function testing in predicting postoperative outcomes. DESIGN MEDLINE search of English-language articles from 1966 to 1987 using the following medical subjects headings respiratory function tests, lung, lung diseases, and preoperative care. MEASUREMENTS AND MAIN RESULTS Relevant studies were subdivided by operative site. We included only studies for which we could determine pre- and post-test probabilities of morbidity, mortality, sensitivity, and specificity. Preoperative pulmonary function testing was found to have measureable benefit in predicting outcome in lung resection candidates. In selected patients, split perfusion lung scanning and pulmonary exercise testing appeared to be useful. Confirmation of these reports is necessary before these preoperative tests can be routinely recommended. In studies of upper abdominal surgery, spirometry and arterial blood gas analysis did not consistently have measureable benefit in identifying patients at increased risk for postoperative pneumonia, prolonged hospitalization, and death. Studies of preoperative testing for other patients, including those having coronary artery bypass grafting, lacked adequate data for meaningful analysis. CONCLUSIONS Preoperative pulmonary function testing helps clinicians to make decisions on management of lung resection candidates. Although many studies of patients before abdominal surgery have focused on the utility of preoperative pulmonary function testing, methodologic difficulties undermine the validity of their conclusions. The impact of testing on care of other preoperative patients is even less clear because of poor study design and insufficient data. Therefore, further investigation is necessary before a consensus can be reached on the role of preoperative pulmonary function testing in evaluating patients before all surgical procedures except lung resection.

Spiral CT With Multiplanar and Three-Dimensional Reconstructions Accurately Predicts Tracheobronchial Pathology

BACKGROUND This study was designed to evaluate the clinical accuracy of multiplanar reconstructions and three-dimensional shaded surface displays compared with conventional transaxial computed tomography, bronchoscopy, and surgical pathologic findings. METHODS Transaxial computed tomographic images, two-dimensional nonstandard multiplanar reconstruction images, and three-dimensional images obtained from patients with tracheobronchial disease were prospectively evaluated for the relationship to adjacent structures, lesion characterization, and surgical anatomic correlation before invasive procedures. RESULTS Compared with conventional transaxial computed tomographic images, multiplanar reconstructions and three-dimensional shaded surface displays provided a correlative map of bronchoscopic and surgical anatomy in patients with benign and malignant tracheobronchial pathology. The longitudinal extent of abnormalities are better demonstrated on the multiplanar reconstruction and three-dimensional images, whereas the transverse extent of disease and relationships to adjacent structures were better shown on axial computed tomographic sections. CONCLUSIONS Three-dimensional and multiplanar two-dimensional images are additive to transaxial computed tomography for evaluation of diseases involving the central airways. They are beneficial for planning invasive procedures. More importantly, they provide consistent, highly accurate measurements for routine follow-up and for future clinical trials.

Interstitial lung disease: raising the index of suspicion in primary care.

Interstitial lung disease (ILD) describes a group of diseases that cause progressive scarring of the lung tissue through inflammation and fibrosis. The most common form of ILD is idiopathic pulmonary fibrosis, which has a poor prognosis. ILD is rare and mainly a disease of the middle-aged and elderly. The symptoms of ILD—chronic dyspnoea and cough—are easily confused with the symptoms of more common diseases, particularly chronic obstructive pulmonary disease and heart failure. ILD is infrequently seen in primary care and a precise diagnosis of these disorders can be challenging for physicians who rarely encounter them. Confirming a diagnosis of ILD requires specialist expertise and review of a high-resolution computed tomography scan (HRCT). Primary care physicians (PCPs) play a key role in facilitating the diagnosis of ILD by referring patients with concerning symptoms to a pulmonologist and, in some cases, by ordering HRCTs. In our article, we highlight the importance of prompt diagnosis of ILD and describe the circumstances in which a PCP’s suspicion for ILD should be raised in a patient presenting with chronic dyspnoea on exertion, once more common causes of dyspnoea have been investigated and excluded.

Isolation and Characterization of a Rat Lung Fraction Enriched in Alveolar Wall Basement Membranes

Separation of lung alveolar basement membranes from interstitial connective tissue protein has proved difficult, and a pure preparation of alveolar wall basement membranes (AWBM) is not available. We have modified a technique employing the detergent Triton X-100 for isolating AWBM from rat lungs by adding a step utilizing human skin collagenase (HSC), a highly purified enzyme obtained from skin fibroblasts that specifically cleaves non-basement membrane collagens. Triton extraction of both lungs yields 15-20 mg of basement membrane-enriched material referred to as crude fraction (CF). Ultrastructural studies show that CF includes both epithelial and endothelial basement membranes that appear similar to their in vivo counterparts and contain heparan sulfate proteoglycans. Extraction of type IV collagen is documented by the appearance of highly glycosylated hydroxylysine. This CF contains minimal amounts of contaminating elastin but significant amounts of interstitial collagens. CF was further purified for biochemical studies by incubation with HSC. HSC solubilized 20% of CF hydroxyproline resulting in a final fraction highly enriched in AWBM. Lung minces incubated in tritiated lysine produced a CF extract rich in newly formed type IV collagen, showing that lung tissue synthesizes AWBM collagen in vitro.

Pirfenidone safety and adverse event management in idiopathic pulmonary fibrosis

Pirfenidone is one of two approved therapies for the treatment of idiopathic pulmonary fibrosis (IPF). Randomised controlled clinical trials and subsequent post hoc analyses have demonstrated that pirfenidone reduces lung function decline, decreases mortality and improves progression-free survival. Long-term extension trials, registries and real-world studies have also shown similar treatment effects with pirfenidone. However, for patients with IPF to obtain the maximum benefits of pirfenidone treatment, the potential adverse events (AEs) associated with pirfenidone need to be managed. This review highlights the well-known and established safety profile of pirfenidone based on randomised controlled clinical trials and real-world data. Key strategies for preventing and managing the most common pirfenidone-related AEs are described, with the goal of maximising adherence to pirfenidone with minimal AEs. Using key strategies to prevent and manage pirfenidone-related AEs can help maximise adherence to pirfenidone http://ow.ly/Veyk30gsFTs

Aspiration pneumonitis following electroconvulsive therapy in patients with gastroparesis

Electroconvulsive therapy (ECT) has a role in the treatment of many depressed patients. It has consistently been found to be as effective (Crow 1984) and as safe (Pitts 1972) as pharmacological treatments for patients with major depression. For severe or psychotic depressions, ECT may well be the treatment of choice (Taylor 1982). Aspiration pneumonitis and adult respiratory distress syndrome (ARDS) have not been reported as complications of ECT, except when treatments were given without muscle relaxants (Perrin 1961). We recently observed two episodes of gastric aspiration associated with ARDS following ECT. Both patients were found to have loss of gastric muscle tone (gastroparesis). These findings suggest that candidates for ECT should be screened for gastroparesis, in addition to other well-recognized conditions that are associated with an increased risk of complications during or following ECT.

Cytoplastic enzyme patterns in isolated hamster pulmonary alveolar type II cells

Three cytoplasmic enzyme patterns were studied in pulmonary alveolar type II cells isolated from normal adult hamster lung: lactate dehydrogenase (total and isoenzymes), peroxidase, and beta-N-acetylglucosaminidase. Enzyme patterns of freshly-isolated type II cells were found to be different from those of freshly-isolated pulmonary hamster fibroblasts. After both types of cells had been cultured for seven days, no difference in cytoplasmic enzyme patterns remained. Lactate dehydrogenase isoenzyme patterns for type II cells were different from those obtained from polymorphonuclear leukocytes and alveolar macrophages. These data may be useful in detecting sources of lung injury by assessment of enzyme patterns in bronchoalveolar lavage fluid.