Chest radiograph interpretation skills of anesthesiologists

OBJECTIVE

To assess the skills of anesthesiologists in the interpretation of chest radiographs.

DESIGN

Randomized evaluation conducted among anesthesiologists and radiologists.

SETTING

Postgraduate Assembly of the New York State Society of Anesthesiologists in 1999, and the Department of Radiology, New York University Medical Center.

PARTICIPANTS

A total of 61 anesthesiologists (48 attending physicians; 13 residents); control group of 8 radiology residents (all participants volunteered).

INTERVENTIONS

After completing a demographic survey, participants were asked to review a series of 10 chest radiographs. A brief clinical scenario accompanied each radiograph. No time limit was set for these interpretations.

MEASUREMENTS AND MAIN RESULTS

The demographic characteristics of the anesthesiology participants included university faculty (46%), private group practitioners (41%), independent practitioners (11%), and 1 participant with an unspecified type of practice. Additional training among the participants included internal medicine (31%), surgery (19%), and pediatrics (3%); 34% did not specify any additional training. Of the participants, 92% were involved in cases requiring general anesthesia; 96% managed patients in the recovery room; and 34% managed patients in the intensive care unit. Of participants, 80% usually order chest radiographs, but only 42% interpret the films themselves. Misdiagnosed radiographs included pneumothorax by 11% of participants, free air under the diaphragm by 41%, bronchial perforation from a nasogastric tube by 28%, right mainstem intubation by 20%, superior vena cava perforation from a central venous catheter by 31%, normal film by 75%, negative pressure pulmonary edema by 16%, left lower lobe collapse by 80%, pulmonary infarction from a pulmonary artery catheter by 29%, and tension pneumothorax by 41%. Overall scores of the attending physicians were not significantly different from that of residents (p > 0.05). The control group of radiology residents scored significantly better (mean, 83.7; p = 0.009) than the anesthesia residents (mean, 62.8) and anesthesia attending physicians (mean, 62.5).

CONCLUSION

Anesthesiologists are deficient in skills for the interpretation of chest radiographs. The skill level of university-based physicians is not greater than physicians in private practice, and skill level does not improve with level of training or experience. Most anesthesiologists rely on radiologists for interpretative results. Further training during the residency years may help improve diagnostic skills.

Variables affecting pulmonary nodule detection with computed tomography: evaluation with three-dimensional computer simulation

To meaningfully evaluate factors determining the overall accuracy of computed tomography (CT) for identifying pulmonary nodules, computer-generated nodules were superimposed on normal CT scans and interpreted independently by three experienced chest radiologists. Variables evaluated included nodule size, shape, number, density, location, edge characteristics, and relationship to adjacent vessels, as well as technical factors, including slice thickness and electronic windowing. The overall sensitivity in identifying nodules was 62% and the specificity was 80%. On average, the observers identified 56, 67, and 63% of nodules on 1.5-, 5-, and 10-mm-thick sections, respectively (p = 0.037). Nodules were more difficult to identify on 1.5-mm-thick sections. On average, observers identified 1, 48, 82, and 91% of nodules < 1.5, < 3, < 4.5, and < 7 mm in diameter, respectively (p < 0.001). Other factors that made a significant contribution (p < 0.01) in identifying nodules, as determined by linear discriminant function analysis, included nodule location, angiocentricity, and density. We concluded that computer-generated nodules can be used to assess a large number of imaging variables. We anticipate that this approach will be of considerable utility in assessing the accuracy of interpretation of a wide range of pathologic entities as well as in optimizing three-dimensional scan protocols within the thorax.

High resolution CT findings in miliary lung disease

High-resolution CT (HRCT) and chest radiographs were compared in nine patients with miliary lung disease. In all cases, miliary disease was documented to be infectious in etiology; six of these patients proved to be human immunodeficiency virus (HIV) positive. A mixture of both sharply and poorly defined 1-3 mm nodules was seen in all cases, many of the latter having an appearance indistinguishable from airspace nodules. Other features attributable to the presence of nodules included nodular interlobular septae, nodular irregularity of vessels, subpleural dots, and studded fissures. Diffuse intra- and interlobular septal thickening also proved common, seen in all but one case (91%). Based on limited HRCT-pathologic correlation, CT findings appear primarily to be due to granulomatous foci developing in a seemingly random distribution involving both pulmonary airspaces as well as the interstitium. It is concluded that in the appropriate clinical setting this constellation of findings is characteristic of miliary disease; the role of HRCT especially in the early diagnosis of miliary disease in HIV positive patients remains to be determined prospectively.