Other factors predicting in hospital mortality were altered level of consciousness and relative lack of experience with tPA treatment in the center. Altered level of consciousness was a predictor of stroke severity and an independent predictor of in-hospital mortality (OR 3.4). The increase in mortality in centers with limited experience with tPA administration (OR 0.97) reflected learning curve issues with these patients. The study was not designed to separate out the confounders of operator experience curve from institutional experience curves, or to derive the exact relationship between experience and outcomes.
5. McAlister FA, Bertsch K, Man J, et al. Incidence of and risk factors for pulmonary complications after non-thoracic surgery. Am J Respir Crit Care Med. 2004; published ahead of print on November 24, 2004 as doi:10.1164/rccm.200408-1069OC. Accessed January 27, 2005.
Postoperative pulmonary complications after nonthoracic surgery are a cause of significant morbidity and increased length of hospital stay. Previous studies of preoperative pulmonary assessment were limited by non-representative patient samples, conflicting results, and lack of explicit definitions of these complications. The authors conducted a prospective cohort study of 1055 patients seen in a Pre-Admission Clinic of a tertiary care university hospital. Mean age was 55 years, 50% male, and the cohort consisted of patients scheduled for intermediate risk elective surgery (upper abdominal, lower abdominal, orthopedic). They evaluated physical exam maneuvers (cough test, wheeze test, maximal laryngeal height, and forced expiratory time, all of which are described in an online data supplement) and preoperative spirometry values, and collected information on clinically significant postoperative pulmonary complications, including pneumonia, respiratory failure requiring mechanical ventilation, atelectasis requiring bronchoscopy, or pneumothorax or pleural effusion requiring percutaneous intervention. Twenty-eight patients (2.7%) suffered a pulmonary complication within 7 days of surgery, one of whom died. Length of stay was significantly prolonged in this group (mean 27.9 days vs 4.5 days, p=.006). Multivariate regression analysis revealed four variables that were independently associated with increased risk for postoperative pulmonary complications: age > 65 years, positive cough test (repeated coughing after asking the patient to inhale deeply and cough once), perioperative nasogastric tube, and anesthesia duration 2.5 hours or greater. Number of pack years smoked, FEV1, FEV1/FVC ratio, and upper abdominal surgery were associated with postoperative pulmonary complications but were not found to be independently associated by multivariate analysis.
While it is not surprising that the above risk factors are predictive of postoperative complications, this is the first study to incorporate specific exam maneuvers and spirometry into a risk prediction analysis. Limitations of this model are lack of independent validation and lack of generalizability to other populations, e.g., inpatients awaiting urgent surgery. Of note, the study further provides further support for not routinely obtaining pulmonary function testing for risk stratification prior to noncardiac surgery.
6. Mortenson, EM, Restrepo M, Anzeuto A, Pugh J. Effects of guideline-concordant antimicrobial therapy on mortality among patients with community-acquired pneumonia. Am J Med. 2004;117:726-31.
The American Thoracic Society (ATS) and the Infectious Diseases Society of America (IDSA) have published guidelines for the management of community acquired pneumonia that include recommendations for antibiotic selection. This retrospective cohort study attempted to measure the association between adherence to such guidelines and 30-day mortality in patients admitted with pneumonia to two Texas hospitals.
The characteristics of the patients studied reflect a reasonable cross-section of typical pneumonia patients, with the exception that the patients were mostly (85%) men. Of the study population, 78% were admitted through the ER, 20% admitted to the ICU, and 9% were nursing home residents. Antibiotics were considered “concordant” if they were consistent with either the most recent IDSA or ATS recommendations. The “nonconcordant” group was slightly older (66 vs. 61), generally sicker (higher rate of comorbid COPD and CVD), had more cerebrovascular disease, was more likely to present with altered mental status, and less frequently received antibiotics within 8 hours of presentation. The study did not comment on patients’ vaccination status. Thirty-day mortality was 6.2% in the guideline-concordant group, versus 21.7% in the other group (p < .001). The most common “non-concordant” regimen described was use of a beta-lactam alone, although specific antibiotic regimens were not evaluated.