Routine chest x-ray examinations

An audit of 3859 preadmission chest radiographs of apparently healthy students in a Nigerian Tertiary Institution

BACKGROUND

Chest radiographs are routinely requested as part of the medical screening process prior to admission to institutions. Literature on the yield of such an exercise is sparse especially in the Nigerian setting. This study was therefore carried out to assess the usefulness of routine chest radiography for students at the time of admission.

MATERIALS AND METHODS

This was a prospective study of 3859 chest X-rays taken at the department of radiology, University of Benin Teaching Hospital for one admission screening for the 2008/2009 academic year. The age and sex of the subjects were also recorded. The heart, lung fields and bony thorax were examined for any abnormality.

RESULTS

Out of the 3859 pre-admission chest radiographs studied, there were 1951 males or 50.56% and 1908 females or 49.44% subjects. The mean age for males was 21.15±3.

CONCLUSION

This study has shown that pre-admission routine chest radiography in asymptomatic patients remains a relevant screening tool for medical fitness during admissions into institutions. However because of dangers of exposure to ionizing radiation, we advise that a detailed medical history and physical examination be done to restrict its use to only those subjects with signs and symptoms suggestive of disease.

Routine Chest Radiography in a Primary Care Setting

PURPOSE

To determine the frequency, diagnostic yield, outcomes, cost, and rate of false-positive results of routine chest radiography performed in asymptomatic patients in the primary care setting.

MATERIALS AND METHODS

Radiography reports on all patients who underwent routine or screening posteroanterior and lateral chest radiography at a university-affiliated primary care clinic in 2001 were reviewed. Radiographic results were coded as normal or minor findings or as major abnormalities, such as pulmonary nodules, requiring further diagnostic evaluation. Outcomes of patients with major abnormalities were established by using chart reviews or reviewing additional radiographs. Costs were estimated by using 2002 Medicare reimbursement rates. The main measures assessed were frequency, costs, and rate of false-positive results of routine chest radiography.

RESULTS

Of 3812 radiographs obtained at the primary care clinic, 1282 (34%) were ordered for routine or screening purposes by the referring physician. Nine hundred twenty-two radiographs were obtained in male patients and 360 were obtained in female patients; their mean and median age was 49 years (age range, 4-87 years). Fifteen chest radiographs showed major abnormalities. No patient younger than 40 years had a major abnormality. Fourteen of the 15 findings of major abnormalities proved to be false-positive. No disease requiring treatment was diagnosed as a result of radiographic findings. The total cost for follow-up radiography and computed tomography was US dollar 46,609.49.

CONCLUSION

Routine chest radiography has low diagnostic yield in asymptomatic primary care patients.

Routine chest roentgenography on admission to intensive care unit after heart operations: is it of any value?

The need for routine immediate postoperative chest roentgenography after heart operations has recently been questioned. In this study we investigated the impact of routine postoperative chest roentgenography on treatment instituted in the cardiovascular intensive care unit immediately after heart operations done via median sternotomy. A total of 404 random patients admitted to the cardiovascular intensive care unit underwent clinical (positioning of endotracheal tube, nasogastric tube, and pulmonary artery catheter) and laboratory (oxygenation) assessment by a cardiovascular intensive care unit physician according to a strict protocol. After clinical assessment, chest roentgenography was done for all admitted patients and the findings reviewed by the same physician. Pathologic conditions noted were recorded on the study form together with any required treatment. Eighteen patients (4.5%) out of 404 required intervention because of abnormalities detected by the chest x-ray film but not predicted by the initial physical and laboratory assessment. None of the pathologic conditions detected was life threatening. We conclude that chest roentgenography done on admission to the cardiovascular intensive care unit should be done only if clinical and laboratory assessment indicate the possibility of underlying pathologic conditions that can only be confirmed or diagnosed by chest roentgenography.

Review of systems, physical examination, and routine tests for case-finding in ambulatory patients

The screening value of the comprehensive review of systems and the complete physical examination in detecting unsuspected diseases for which therapeutic interventions are initiated has not been formally studied in ambulatory patients. The medical records of 100 randomly selected adult patients who had an ambulatory general medical evaluation at the Mayo Clinic in 1990-1991 were surveyed to compare review of systems and physical examination with routine laboratory tests, chest radiography, and electrocardiography as case-finding maneuvers. The main outcome measure was the therapeutic yield of each case-finding maneuver, defined as the proportion of maneuvers leading to a new therapy for a new clinically important diagnosis. The utilization rate of routine tests in the 100 patients (mean age: 59 +/- 16 years; 58% women) was high, ranging from 77 to 98%. Overall, the case-finding maneuvers led to 36 unsuspected clinically important diagnoses and resulted in 25 new therapeutic interventions. Higher therapeutic yield was observed for review of systems (7%), physical examination (5%), and lipid screening (9.2%) than for chemistry group (2.2%), complete blood count (1.8%), thyroid tests (1.5%), urinalysis (1.1%), electrocardiography (0%), or chest radiography (0%). The number of therapeutic interventions was not associated with patient's age (P = 0.55), sex (P = 0.88), comorbidity (P = 0.30) or with the time interval since the last general medical evaluation (P = 0.12). Based on therapeutic yield, these data suggest that review of systems and physical examination are valuable case-finding maneuvers in the periodic medical evaluation of ambulatory patients.

Value of routine preoperative chest x-rays: a meta-analysis

The purpose of this study was to estimate the frequency with which routine postoperative chest x-rays lead to clinically relevant new information. All articles in English, French and Spanish relating to routine chest radiography in North American or European populations were reviewed, using the Medline database and references listed in reviews and periodicals published from 1966 to 1992, inclusive. Twenty-one reports which supplied sufficient information were included for meta-analysis. On average, abnormalities were found in 10% of routine preoperative chest films. In only 1.3% of films were the abnormalities unexpected, i.e., were not already known or would not otherwise have been detected (95% CI: 0 to 2.8%). These findings were of sufficient importance to cause modification of management in only 0.1% (95% CI: 0 to 0.6%). The frequency with which the new information influenced health could not be estimated. Assuming only the direct cost to the health care system of each radiograph ($23), each finding which influenced management in any way would cost $23,000. It is concluded that in North American or European populations when a reliable history and a clinical examination are carried out, the cost of this test is so high relation to the clinical information provided that it is no longer justifiable.

Effect of forced unilateral nostril breathing on blink rates: relevance to hemispheric lateralization of dopamine

The involuntary blink rate is a clinical monitor of dopaminergic activity. Since there is disagreement in the literature on the relative neurochemical hemispheric asymmetry or laterality of dopamine, we studied the effects of differential forced unilateral nostril breathing on blink rate. This technique has been demonstrated to induce selective contralateral hemispheric stimulation as measured by relative increases in the EEG amplitude as well as alternating lateralization of plasma catecholamines. We used the artifact of the two-channel electro-oculogram to measure the endogenous eyeblink in an N = 1 design with 11 reversals of left vs. right hemisphere activation. There was a significant increase in blink rate (p less than .01) with right hemisphere activation, and this suggests that dopamine may be lateralized to the right cerebral hemisphere.

Clinical effect of admission chest X-rays in Zimbabwe

The independent effect of admission chest X-rays on clinical management of 432 consecutive patients admitted to general medical wards was prospectively evaluated. Diagnosis, investigations, and treatment were recorded on the basis of clinical findings alone. A chest X-ray was then taken and clinical effect measured by the resultant changes. Although 226 (53%) admission chest X-rays were abnormal, only 9% changed management. In patients with no clinical evidence of cardiorespiratory disease ("routine" X-rays, n = 214) the clinical effect was slight; management was changed in 5% and patient benefit resulted in 1.4%. Clinical effect was greatest in patients (n = 172) with definite signs of new cardiorespiratory illness (altered management 14%, patient benefit 6%) and patients (n = 34) with "possible" chest disease (altered management 9%, patient benefit 9%). Omission of admission chest X-rays in patients with no clinical evidence of chest disease, those with clinically stable, known chest disease, and those with isolated cardiomegaly or hyperinflated lungs would result in a 60% reduction in the number of admission chest X-rays.

Chest roentgenogram in pulmonary tuberculosis. New data on an old test

The utility of routine admission chest roentgenograms (CXRs) was evaluated in detecting pulmonary tuberculosis and the relationship between roentgenographic patterns and the likelihood of finding acid-fast bacilli (AFB) on sputum smear. Of 58 patients whose chief complaints were unrelated to pulmonary tuberculosis, the CXR suggested tuberculosis in 52 cases (90 percent). In 45 cases, the emergency room physician failed to elicit the patient's respiratory symptoms and did not consider tuberculosis as a diagnostic possibility. In 18 individuals, the diagnosis was missed in the emergency room because of failure to obtain a CXR. Among patients whose roentgenograms showed cavitation or extensive alveolar infiltrate, sputum smears showed AFB in 98 percent of cases. If alveolar infiltrate was absent, or if the roentgenographic pattern was not that of adult reactivation disease, sputum smears revealed AFB in only one half of the cases. We conclude that routine admission CXRs are useful in hospitals serving populations where tuberculosis is still common, and the probability of detecting AFB on sputum smear is greatly influenced by the roentgenographic findings.

An N of 1 service: applying the scientific method in clinical practice

The N of 1 service at our institution acts as a full referral service for clinicians who want a definitive answer to a difficult management question, and an instructional environment for clinicians who have more time and want to learn to run their own N of 1 RCT. The trial design is a double blind, randomized pair, multiple crossover. A number of methodologic issues are discussed, such as appropriateness of the patients problem to N of 1 trials, feasibility, types of measurement, such as clinical objective measurement and quality of life measurement, as well as timing of these measurements. The analysis issues include developing a reporting method which is statistically powerful and understandable to clinicians with little research background. Some of these issues have been well investigated and some have not.