Often, while pneumonia was listed by the ED physician as one of the final diagnoses, heart failure or exacerbation of COPD was also mentioned, and frequently was listed above pneumonia. In six of these cases, the reviewers felt that antibiotic treatment would have been appropriate for any alternative diagnosis (usually an acute exacerbation of COPD), but it would have been appropriate for the ED physician to defer the antibiotic choice to the admitting physician.
Among these 19 cases, there was initial interobserver disagreement for 14 cases (74%). There were three specific reasons for initial disagreement. In two cases, a reviewer overlooked a key piece of the data in the record, and once this was pointed out he changed his opinion. More often, the differences were due to diagnostic uncertainty.
There were disagreements over how likely the diagnosis of pneumonia was for specific patients. In addition, there was not complete agreement on how likely the diagnosis of pneumonia should be before the ED physician should administer antibiotics. This arose most frequently in patients who clearly had respiratory symptoms but could have had pneumonia, heart failure, or an acute exacerbation of COPD. Although there is obviously no “correct” answer, the discussion of this issue can be paraphrased as follows: at what threshold should antibiotics be administered by the ED physician? Should antibiotics be administered only if the physician is nearly certain that the patient has pneumonia, or even if there is only 20% certainty?
Among the 86 patients included in the study, 8 (9%) were admitted directly to the hospital with a suspicion of pneumonia. Since there was no chance of diagnostic uncertainty and there are significant differences in how care is delivered to patients who are not admitted to the hospital through the ED, such patients were excluded from the analyses of the factors associated with diagnostic uncertainty and antibiotic timing. Table 1 demonstrates the demographic and clinical characteristics as well as the timing of antibiotic administration for the remaining 78 patients, stratified by whether or not there was diagnostic uncertainty. this
Table 1—The Associations Among Diagnostic Uncertainty, Patient Characteristics, and Antibiotic Timing
|Variables||Diagnostic Uncertainty (n = 19)||No Diagnostic Uncertainty (n = 59)||p Value|
|Age > 80 yr||12 (63.2)||30 (50.8)||0.349|
|Male gender||9 (47.4)||31 (52.5)||0.695|
|Admitted to hospital from home||13 (68.4)||43 (72.9)||0.707|
|Heart failure||11 (57.9)||26 (44.1)||0.294|
|Cough||13 (68.4)||42 (71.2)||0.818|
|Sputum||9 (47.4)||23 (39.0)||0.518|
|Dyspnea||13 (68.4)||40 (67.8)||0.960|
|Chest Pain||5 (26.3)||9(15.3)||0.275|
|Any of the previous four vs none||16 (84.2)||50 (84.7)||0.955|
|Acute mental status changes||8(42.1)||14 (23.7)||0.122|
|Physical examination/diagnostic data|
|Rales||12 (63.2)||50 (84.7)||0.043|
|Fever||7 (36.8)||26 (44.1)||0.579|
|Oxygen desaturation (< 92%)||6(31.6)||39 (66.1)||0.008|
|Abnormal WBC count||12 (63.2)||40 (67.8)||0.709|
|Infiltrates on chest radiograph||9 (47.4)||50 (84.7)||< 0.001|
|Mean time to first administration of antibiotics, min||303||215||0.210|
|Antibiotic treatment within 4 h||13 (68.4)||44 (74.6)||0.599|