A comparison of two antimicrobial-impregnated central venous catheters. Catheter Study Group.

BACKGROUND: The use of central venous catheters impregnated with either minocycline and rifampin or chlorhexidine and silver sulfadiazine reduces the rates of catheter colonization and catheter-related bloodstream infection as compared with the use of unimpregnated catheters. We compared the rates of catheter colonization and catheter-related bloodstream infection associated with these two kinds of antiinfective catheters. METHODS: We conducted a prospective, randomized clinical trial in 12 university-affiliated hospitals. High-risk adult patients in whom central venous catheters were expected to remain in place for three or more days were randomly assigned to undergo insertion of polyurethane, triple-lumen catheters impregnated with either minocycline and rifampin (on both the luminal and external surfaces) or chlorhexidine and silver sulfadiazine (on only the external surface). After their removal, the tips and subcutaneous segments of the catheters were cultured by both the roll-plate and the sonication methods. Peripheral-blood cultures were obtained if clinically indicated. RESULTS: Of 865 catheters inserted, 738 (85 percent) produced culture results that could be evaluated. The clinical characteristics of the patients and the risk factors for infection were similar in the two groups. Catheters impregnated with minocycline and rifampin were 1/3 as likely to be colonized as catheters impregnated with chlorhexidine and silver sulfadiazine (28 of 356 catheters [7.9 percent] vs. 87 of 382 [22.8 percent], P<0.001), and catheter-related bloodstream infection was 1/12 as likely in catheters impregnated with minocycline and rifampin (1 of 356 [0.3 percent], vs. 13 of 382 [3.4 percent] for those impregnated with chlorhexidine and silver sulfadiazine; P<0.002). CONCLUSIONS: The use of central venous catheters impregnated with minocycline and rifampin is associated with a lower rate of infection than the use of catheters impregnated with chlorhexidine and silver sulfadiazine.

Causes of fever and pulmonary densities in patients with clinical manifestations of ventilator-associated pneumonia.

BACKGROUND: Ventilator-associated pneumonia, a leading cause of sepsis in patients with acute respiratory failure, is difficult to distinguish clinically from other processes affecting patients receiving mechanical ventilation. We conducted a prospective study of patients with suspected ventilator-associated pneumonia to identify the causes of fever and densities on chest radiographs and to evaluate the diagnostic yield and efficiency of tests used alone and in combination. METHODS: The 50 patients entered into the study underwent a systematic diagnostic protocol designed to identify all potential causes of fever and pulmonary densities. Diagnoses responsible for fever were established by strict diagnostic criteria for 45 of the 50 patients. The prevalence of specific conditions and diagnostic yield of individual tests were used to formulate a simplified diagnostic protocol. RESULTS: The diagnostic protocol identified 78 causes of fever (median 2 per patient). Infections were the leading causes of fever and pulmonary densities. Of the 45 patients with fever, 37 had one or more infections identified (67 sources). Most infections (84 percent) were one of four types:pneumonia, sinusitis, catheter-related infection, or urinary tract infection. Ventilator-associated pneumonia occurred in only 42 percent. All but nine infections (87 percent) were directly or indirectly related to insertion of a catheter or a tube. Concomitant infections were frequent (62 percent), particularly in patients with sinusitis (100 percent), catheter-related infections (93 percent), and pneumonia (74 percent). Of concomitant infections, 60 percent were caused by a different pathogen. Noninfectious causes of fever were more common in the 22 patients with adult respiratory distress syndrome. Histologically proved pulmonary fibroproliferation was the only cause of fever in 25 percent of patients with adult respiratory distress syndrome. Radiographic densities were caused by an infection in only 20 patients (19 pneumonia, 1 empyema). In more than 50 percent of the 25 patients without adult respiratory distress syndrome, congestive heart failure, and atelectasis were the sole causes of pulmonary densities, and fever always originated from an extrapulmonary site of infection. Used in combination, bronchoscopy with protected sampling, computed tomographic scan of the sinuses, and cultures of maxillary sinus aspirate, central intravenous or arterial lines, urine, and blood identified 58 of the 78 sources of fever (74 percent). CONCLUSIONS: The observations in this study document the complex nature of acute respiratory failure and fever and underscore the need for accuracy in diagnosis. The frequent occurrence of multiple infectious and noninfectious processes justifies a systematic search for source of fever, using a comprehensive diagnostic protocol. A simplified diagnostic protocol was devised based on the diagnostic value of individual tests.

Mechanical complications from insertion of subclavian venous feeding catheters: comparison of de novo percutaneous venipuncture to change of catheter over guidewire.

Since a percutaneous catheter insertion into the subclavian vein can be tedious, time consuming, and risky, we have compared the morbidity of 137 de novo subclavian catheter insertions to that of 93 reinsertions over guidewire. Mechanical complications were significantly higher (p less than 0.03) in those with catheter insertions (8.8%) than in those with the guidewire insertions (2.2%). These included pneumothorax (4), arterial puncture (4), catheter-size bleed (3), and hemothorax (1) in the catheter insertion group and local bleeding (1) and hydrothorax (1) in the guidewire insertion group. The difference in complications between methods is probably inherent in the techniques. Operator experience was not a factor: 55% of the physicians in each group had previously done less than 26 subclavian venous catheterizations. Preliminary analysis indicates that the infection rate, as determined by semiquantitative, cultures, is the same in each group. When considering the equal potential for infection, we conclude that change over a guidewire is an acceptable alternative to contralateral de novo percutaneous subclavian venipuncture for feeding catheter insertion. In view of fewer mechanical complications and greater ease of insertion, change of subclavian feeding catheters by guidewire is probably the method of choice.

Fungus balls of the urinary tract.

Fungus balls of the urinary tract are rare and usually associated with infection by Candid albicans. Since 1968 five patients seen at the Medical College of Virginia Hospitals presented with this peculiar manifestation of candidiasis. Summaries of their epidemiologic clinical, pathologic, and mycologic data are presented. All Candida fungus balls involved the upper collecting system and were detected by radiography and confirmed by culture and/or pathologic section. Two of the five patients completely recovered. Three patients were treated with flucytosine and/or local irrigation with a polyene antifungal agent. Two recovered and the third died of probable bacterial sepsis. One patient was treated successfully with surgical removal of the fungus ball and a brief period of local irrigation with amphotericin B (AMB). The fifth patient recovered after 28 days of parenteral AMB. Predisposing factors and pathogenetic mechanisms are discussed, and a rational approach to therapy is outlined.