Comparison of toxicity induced by HT-2 toxin on human and rat granulo-monocytic progenitors with an in vitro model

Catheter-associated bloodstream infections remain an important cause of nosocomial infection, with an estimated 50,000-100,000 cases occurring each year in the United States. Central venous catheters are believed to be responsible for 90% of such infections. The cumulative risk of acquiring a catheter-related bloodstream infection has ranged between 1 and 10% for central venous catheters in general and 6% for total parenteral nutrition catheters. The skin is the most common source of organisms causing catheter-related infections. Recent prospective studies have shown that the incidence density per catheter day does not increase with duration of catheterization and that routine changes, either over a guidewire or by new site puncture, do not appear to lower the risk of infection. Diagnosis of infection can be difficult in intensive care patients but is usually easier in less ill patients with a central venous catheter. Quantitative or semiquantitative laboratory techniques can be used to confirm the diagnosis in the appropriate clinical setting. A variety of preventive measures have been shown to minimize the risk of development of catheter-related bloodstream infection, including use of maximal aseptic technique for insertion, use of special teams for care of the catheter, limiting manipulation of the catheter, use of povidone-iodine ointment and cotton gauze dressings for recently inserted catheters, a silver-impregnated collagen cuff and antiseptic-impregnated catheters.     

Central venous catheters. Prospective surveillance of a hospital

OBJECTIVES: All the central venous catheters (CVC) inserted at the Saint-Antoine Hospital between December 5, 1994 and June 6, 1995 were prospectively studied in order to better define practices in the management of CVC and to determine the rate of catheter-related infections. METHODS: The following data were recorded for each CVC: insertion procedure, clinical data, catheter dressings, removal, catheter-related infections, bacteriological findings. Catheter-related infections were distinguished from probably catheter-related infections and localized skin infections. RESULTS: Among 325 patients, a total of 414 catheters were inserted. At the end of the surveillance period, 350 (85%) had been removed, 43 (10%) were still in place and 21 (5%) were lost to follow-up. Analysis of procedures such as cutaneous disinfection, routine replacement of the i.v. sets or changes of dressings showed wide variations between care units and within the same unit. The overall incidence of catheter-related infections was 0.24 per 100 days of catheterization. Infections occurred 29 +/- 34 days after insertion. Microorganisms responsible for catheter-related bacteremia were mostly Gram positive (84%) and Gram negative (16%). Sixty-two infections (15%) were clinically suspected by physicians, leading to the catheter removal in 84% of cases. Out of the 43 CVC sent to the laboratory, 29 (67%) were negative (i.e., "sterile") in quantitative culture of the tips as described by Brun-Buisson, suggesting that the CVC was unnecessarily removed. Bacteriological analysis ordered by physicians were not always relevant. For example, 76% of CVC received by the laboratory were systematically sent although they were not suspected of infections. Conversely, only 61% of exsudate formation at the insertion site were collected and analyzed. CONCLUSION: This study was designed to recall good guidelines to the hospital staff. Results will lead to the development of a better use of antiseptics and to the implementation of appropriate and standardized procedures to reduce risk infection.     

Nosocomial colonization, septicemia, and Hickman/Broviac catheter-related infections in bone marrow transplant recipients. A 5-year prospective study

In this 5-year prospective study of 242 bone marrow transplantation (BMT) recipients from whom daily blood cultures via the indwelling Broviac/Hickman catheter were obtained, there was a median of 35 catheter-days during hospitalization, mean of 40 days, and total of 9,667 catheter-days which were divided almost equally between neutropenic (4,771) and non-neutropenic (4,896) days. One hundred twenty (50%) patients had a total of 161 episodes of nosocomial bacterial or candidal infections. Overall, 81 (33%) patients experienced 100 episodes of catheter-related infections and 90 (37%) patients experienced 112 episodes of septicemia, including 51 episodes of catheter-related septicemia. There was an incidence of 11.59 septicemia episodes, including 5.28 catheter-related septicemia episodes, 2.48 colonization only (without subsequent septicemia), and 2.59 exit site infections only, per 1,000 catheter-days. Over a period of a total of 6,593 afebrile days, 34 (14%) patients developed 40 episodes of colonization, a rate of 6.07 per 1,000 afebrile days, of which 16 developed into septicemia. Twenty-five patients had 1 episode each of exit site infection without bacteremia. There were 10 (4%) septicemia-related deaths, 4 of which were catheter-related; 50% of all deaths involved Pseudomonas aeruginosa. The mortality due to catheter-related septicemic episodes was not greater than that of the non-catheter-related episodes. Neutropenia was found to be a significant risk factor in our study: 76% of the septicemia episodes (85/112) and 65% of the catheter-related infectious episodes (65/100) occurred during neutropenia. There was a higher incidence of septicemic episodes during neutropenia than during non-neutropenic periods, 17.82 versus 5.51 per 1,000 days (p < 0.0001), and a higher rate of catheter-related infections during the neutropenic period, 13.62 versus 7.15 during non-neutropenic days per 1,000 days (0.001). Fourteen of 16 colonization episodes developed into septicemia during neutropenia versus 2/24 during non-neutropenic periods, a rate of 5.47 versus 0.47 per 1,000 afebrile days, respectively (p < 0.0001), and 9/10 deaths occurred during neutropenia.     

Pulsed Doppler ultrasonography guidance for catheterization of the subclavian vein: a randomized study

BACKGROUND: Catheterization of the subclavian vein may lead to severe complications. The current randomized study compared a technique of pulsed Doppler ultrasonography guidance and the standard method for subclavian vein catheterization. METHODS: Standard and Doppler ultrasonography guidance methods were performed by the same physician in 286 patients, 143 in each group. Primary end points were immediate complications (arterial puncture, pneumothorax, wrong position of catheter tip), failures, the number of subclavian vein catheterizations with immediate complication or failure, the number of skin punctures per catheterization, and the time to placement of the guide wire. The secondary end points were the determination of predicting factors of successful cannulation in each group. RESULTS: Both groups were similar according to morphologic parameters of the patients. A greater number of subclavian vein catheterizations were performed on the right side using Doppler guidance (105 vs. 73, P < 0.01). Doppler guidance decreased complications (5.6% vs. 16.8%, P < 0.01), largely because of a smaller number of catheters for which the tip was defined to be in incorrect position (0.7% vs. 7.7%, P < 0.01). The time to catheterization was longer with Doppler guidance (300 vs. 27 s, P < 0.001). Failures, catheterizations of the subclavian vein with immediate complications or failure, and the total number of skin punctures per catheterization were similar in both groups. Using Doppler guidance, the presence of a good Doppler signal (124 of 143) was predictive of successful catheterization (123 successful cannulations, P < 0.001). CONCLUSIONS: Doppler guidance reduces the incidence of inappropriately positioned subclavian catheters.     

Epidemiology of nosocomial infections

The frequency of nosocomial infections lies between 5 and 10%, and varies according to the type of hospital and service. Age, underlying disease invasive devices (such as catheters) or procedures are the main risk factors. Common nosocomial infections are urinary tract infections, pneumonia, surgical site infections, bacteremia/septicemia and intravascular catheter-related infections. Gram positive cocci and gram negative bacilli account for one third and two thirds of microorganisms respectively, Staphylococcus aureus being frequently resistant to antibiotics. Prevention is based on a better control of infection risk related to the use of invasive devices.     

Urinary tract infections

Urinary tract infections are common clinical problems which result in significant morbidity and even mortality. UTI's can range from minimal disease to life-threatening sepsis and it is important to differentiate between the former which usually involves the lower urinary tract and the latter which invariably involves the upper urinary tract. Diagnosis depends on an abnormal urine microscopy and demonstration of bacteria in the urine. Pre-therapy urine cultures are not mandatory in young women with uncomplicated UTI and many studies support the efficacy of short-course therapy in this groups of patients. For other patients, microbiological and radiological investigations are required and there is insufficient data to support short course therapy in these patients. Treatment guidelines are different in special situations such as prostatitis, pregnancy, catheter-related infection and recurrent infections.     

Tunneling short-term central venous catheters to prevent catheter-related infection: a meta-analysis of randomized, controlled trials

OBJECTIVE: To evaluate the efficacy of tunneling short-term central venous catheters to prevent catheter-related infections. DATA SOURCES: MEDLINE, EMBASE, conference proceedings, citation review of relevant primary and review articles, personal files, and contact with expert informants. STUDY SELECTION: From a pool of 225 randomized, controlled trials of venous and arterial catheter management, we identified 12 relevant trials and included seven of these trials in the analysis. DATA EXTRACTION: In duplicate, independently, we abstracted data on the population, intervention, outcomes, and methodologic quality. DATA SYNTHESIS: Tunneling decreased bacterial colonization of the catheter by 39% (relative risk of 0.61; 95% confidence interval [CI] of 0.39 to 0.95) and decreased catheter-related sepsis with bacteriologic confirmation by 44% (relative risk of 0.56; 95% CI of 0.31 to 1) in comparison with standard placement. The majority of the benefit in the decreased rate of catheter-sepsis came from one trial at the internal jugular site (relative risk of 0.30, 95% CI of 0.10 to 0.89) and the reduction in risk was not significant when the data from five subclavian catheter trials were pooled (relative risk of 0.71, 95% CI of 0.36 to 1.43). Tunneling was not associated with increased risk of mechanical complications from placement or technical difficulties during placement. However, this outcome was not rigorously evaluated. CONCLUSIONS: Tunneling decreases central venous catheter-related infections. However, current evidence does not support routine tunneling until its efficacy is evaluated at different placement sites and relative to other interventions.     

Correlates of lens thickness: the Beaver Dam Eye Study

Stenosis of the subclavian vein (SVS) after cannulation occurs in 15 to 50% of chronic hemodialysis patients, and impedes the placement of an arteriovenous fistula in the ipsilateral arm. Its natural history and pathogenic mechanisms are not well established. This study examined 42 consecutive chronic renal failure patients (28 men and 14 women; 46+/-19 yr) in whom subclavian catheters had been placed as the initial vascular access for hemodialysis. All patients underwent sequential venography studies: at baseline (24 to 48 h after removal of the catheter) and 1, 3, and 6 mo thereafter. Venograms were considered abnormal when there was evidence of unequivocal strictures (more than 30% narrowing), with or without collateral circulation. At baseline, 52.4% (n=22) of patients showed stenotic vein lesions (n=19) or total thrombosis (n=3), and identical lesions were also observed after 1 mo. Surprisingly, 10 of 22 patients with initial SVS (45.4%) showed spontaneous recanalization of venous lesions in the venographies performed 3 mo after removal. The patients with normal baseline venograms (n=20) showed no change during follow-up. Patients with definitive stenosis at 6 mo (n=12) had a higher number of inserted catheters (1.58+/-0.6 versus 1.2+/-0.48; P < 0.05), longer time in place (49.08+/-32.2 versus 29.03+/-26.6 d; P < 0.05), and higher number of dialysis sessions (21+/-13.8 versus 12.4+/-11.4; P < 0.05) than those without SVS or with spontaneous recanalization of venous lesions during follow-up. Furthermore, a higher number of catheter-related infections were observed in patients with definitive SVS (66.6% versus 33.3%; P < 0.05). In summary, SVS is observed in more than half of patients 24 to 48 h after catheter removal and 1 mo later. Even when recanalization occurs in many cases, a definitive stenosis is seen in 28% of patients by the third month. Thus, the creation of an ipsilateral vascular access is possible provided that venography is normal at this time. Finally, mechanical factors and catheter-related infections are the major risk factors for the development of late SVS.     

Analytical and biologic variability in measures of hemostasis, fibrinolysis, and inflammation: assessment and implications for epidemiology

CONTEXT: Central venous catheters impregnated with chlorhexidine and silver sulfadiazine have recently been introduced for the prevention of catheter-related infections. However, there remains some uncertainty regarding the efficacy of these catheters because of conflicting reports in the literature. OBJECTIVE: To evaluate the efficacy of chlorhexidine-silver sulfadiazine-impregnated central venous catheters in the prevention of catheter-related bloodstream infection. DATA SOURCES: Studies identified from a computerized search of the MEDLINE database from January 1966 to January 1998, reference lists of identified articles, and queries of principal investigators and the catheter manufacturer. STUDY SELECTION: Randomized trials comparing chlorhexidine-silver sulfadiazine-impregnated central venous catheters with nonimpregnated catheters were included. The outcomes assessed were catheter colonization and catheter-related bloodstream infection confirmed by catheter culture. DATA EXTRACTION: Twelve studies met the inclusion criteria for catheter colonization and included a total of 2611 catheters. Eleven studies with a total of 2603 catheters met the inclusion criteria for catheter-related bloodstream infection. Most patients in these studies were from groups considered to be at high risk for catheter-related infections. Summary statistics were calculated using Mantel-Haenszel methods under a fixed-effects model. DATA SYNTHESIS: The summary odds ratio for catheter colonization was 0.44 (95% confidence interval [CI], 0.36-0.54; P<.001), indicating a significant decrease in catheter colonization associated with impregnated catheters. The studies examining the outcome of primary interest, catheter-related bloodstream infection, had a summary odds ratio of 0.56 (95% CI, 0.37-0.84; P = .005). CONCLUSIONS: Central venous catheters impregnated with a combination of chlorhexidine and silver sulfadiazine appear to be effective in reducing the incidence of both catheter colonization and catheter-related bloodstream infection in patients at high risk for catheter-related infections.     

Effects of syntactic structure and propositional number on patterns of regional cerebral blood flow

BACKGROUND: Intravascular catheters are associated with severe infections in patients, but only few reports on this problem in animal research exist. OBJECTIVE: We report on catheter-related bacterial colonization and its consequences in long-term catheterized animals. MATERIAL AND METHOD: Foxhounds were instrumented with intravascular catheters and flow probes to study the regulation of renal blood flow and pressures. RESULTS: After flushing the catheters, alterations in renal blood flow were observed and these could be related to bacterial colonization of intravascular catheters with Pseudomonas species. After attention had been focused on aseptic technique in all experimental phases and prophylactic antibiotic lock instituted, the occurrence of Pseudomonas bacteremia ceased, and the magnitude and incidence of catheter-related colonization and infection by Pseudomonas species dropped considerably. CONCLUSION: The catheter-related colonization that occurred spontaneously in these animals resembled findings in animal experiments in which catheter-related infections were deliberately induced as well as observations made with regard to catheter-related infections in patients. This report emphasizes the importance of asepsis when working with animals with long-term intravascular catheters. We suggest that monitoring for this complication, e.g., by means of catheter cultures at the time of removal, should routinely be part of protocols for animal experiments using long-term intravascular catheters.     

Acinetobacter species as a cause of catheter-related infections

In recent years, Acinetobacter species have emerged as clinically important pathogens. Though these organisms are widely prevalent in nature, most human infections are hospital-acquired. Acinetobacter baumannii is the predominant species. Nosocomial Acinetobacter baumannii infections such as respiratory tract infections, urinary tract infections, meningitis following neurosurgical procedures, and bacteremia mainly affect patients with severe underlying disease in the ICU and often, in the setting of nosocomial outbreak. The occurrence of multiresistant strains often limits therapeutic options. A substantial part of Acinetobacter baumannii bacteremia cases represent catheter-related infections that usually carry a favorable prognosis. Acinetobacter species other than Acinetobacter baumannii are less frequently reported as a cause of infection in humans. Bacteremia due to these organisms is mostly sporadic and almost exclusively related to intravascular devices. The underlying diseases are often less severe than those of patients affected by Acinetobacter baumannii infections. The clinical course is usually benign and the infection responds readily to catheter removal irrespective of the appropriateness of antimicrobial therapy.     

The impact of nosocomial infections on patient outcomes following cardiac surgery

STUDY OBJECTIVE: To evaluate the relationship between nosocomial infections and clinical outcomes following cardiac surgery, and to identify risk factors for the development of nosocomial infections in this patient population. DESIGN: Prospective cohort study. SETTING: Barnes-Jewish Hospital, St. Louis, a university-affiliated teaching hospital. PATIENTS: Six hundred five consecutive patients undergoing cardiac surgery. INTERVENTIONS: Prospective patient surveillance and data collection. MAIN OUTCOME MEASURES: Occurrence of nosocomial infections, multiorgan dysfunction, hospital mortality, and risk factors for the acquisition of nosocomial infections. RESULTS: One hundred thirty-one (21.7%) patients acquired at least one nosocomial infection following cardiac surgery. Four independent risk factors for the development of a nosocomial infection were identified: the duration of mechanical ventilation, postoperative empiric antibiotic administration, the duration of urinary tract catheterization, and female gender. Thirty (5.0%) patients died during their hospitalization. The mortality rate of patients acquiring a nosocomial infection (11.5%) was significantly greater than the mortality rate of patients without a nosocomial infection (3.2%) (odds ratio [OR]=4.0; 95% confidence interval [CI]=2.7 to 5.8; p<0.001). Multiorgan dysfunction was found to be the most important independent determinant of hospital mortality (adjusted OR=23.8; 95% CI=13.5 to 42.1; p<0.001) along with the aortic cross-clamp time (adjusted OR=2.3; 95% CI=1.7 to 3.0; p=0.002) and severity of illness as measured by APACHE II (acute physiology and chronic health evaluation) (adjusted OR=1.1; 95% CI=1.1 to 1.2; p=0.019). Ventilator-associated pneumonia, clinical sepsis, female gender, the cardiopulmonary bypass time, and severity of illness were identified as independent risk factors for the development of multiorgan dysfunction. Among hospital survivors, patients acquiring a nosocomial infection had longer hospital lengths of stay compared to patients without a nosocomial infection (20.1+/-13.0 days vs 9.7+/-4.5 days; p<0.001). CONCLUSIONS: Nosocomial infections, which are common following cardiac surgery, are associated with prolonged lengths of hospitalization, the development of multiorgan dysfunction, and increased hospital mortality. These data suggest potential interventions for the prevention of nosocomial infections following cardiac surgery that could substantially improve patient outcomes and decrease medical care costs.     

Ceptral voice analysis: link with perception and stroboscopy

Osteomyelitis of the clavicle or the sternoclavicular joint is a rare complication of subclavian vein catheterization. Soft tissue infections around the puncture site occur frequently and respond well to topical and antibiotic treatment. If symptoms persist for several weeks, osteomyelitis or sternoclavicular pyo-arthrosis should be considered. Bone and gallium scintigraphy scans and computerized tomography scans are helpful diagnostic measures.     

Trends in antifungal use and epidemiology of nosocomial yeast infections in a university hospital

This report describes both the trends in antifungal use and the epidemiology of nosocomial yeast infections at the University of Iowa Hospitals and Clinics between fiscal year (FY) 1987-1988 and FY 1993-1994. Data were gathered retrospectively from patients' medical records and from computerized databases maintained by the Pharmacy, the Program of Hospital Epidemiology, and the Medical Records Department. After fluconazole was introduced, use of ketoconazole decreased dramatically but adjusted use of amphotericin B decreased only moderately. However, the proportion of patients receiving antifungal therapy who were treated with amphotericin B declined markedly. In FY 1993-1994, 26 patients of the gastrointestinal surgery service received fluconazole. Among these patients, fluconazole use was prophylactic in 16 (61%), empiric in 3 (12%), and directed to a documented fungal infection in 7 (27%). Rates of nosocomial yeast infection in the adult bone marrow transplant unit increased from 6.77/1,000 patient days in FY 1987-1988 to 10.18 in FY 1989-1990 and then decreased to 0 in FY 1992-1993. Rates of yeast infections increased threefold in the medical and surgical intensive care units, reaching rates in FY 1993-1994 of 6.95 and 5.25/1,000 patient days, respectively. The rate of bloodstream infections increased from 0.044/1,000 patient days to 0.098, and the incidence of catheter-related urinary tract infections increased from 0.23/1,000 patient days to 0.68. Although the proportion of infections caused by yeast species other than Candida albicans did not increase consistently, C. glabrata became an important nosocomial pathogen.     

Clinical and microbiological characteristics of Flavobacterium indologenes infections associated with indwelling devices

Clinical infections caused by Flavobacterium indologenes have never been documented. Thirteen isolates derived from seven patients with indwelling device-associated F. indologenes infections were identified from 1 April through 30 November 1995. The antimicrobial susceptibilities to 20 antimicrobial agents of the isolates, the cellular fatty acid chromatograms for the isolates, and the random amplified polymorphic DNA (RAPD) patterns generated by arbitrarily primed PCR of the isolates were studied. The antibiotypes and RAPD patterns differed among the isolates recovered from different patients. However, both antibiotypes and RAPD patterns were identical among the five isolates from one patient with multiple episodes of central venous catheter-associated bacteremia within a 1.5-month period and between the two isolates from another patient suffering from two episodes of catheter-related bacteriuria at an interval of 14 days. It is documented that the recurrent infections in each of these two patients were caused by a single F. indologenes clone, respectively. Identical antibiotypes and RAPD patterns were also demonstrated between two isolates from a patient with ventilator-associated pneumonia, one recovered from an endotracheal aspirate and the other derived from a blood specimen 10 days later, indicating the invasive nature of F. indologenes. Two cellular fatty acid chromatograms were identified among these isolates. All of the isolates showed in vitro resistance to cephalothin, cefotaxime, ceftriaxone, moxalactam, aztreonam, aminoglycosides, erythromycin, clindamycin, vancomycin, and teicoplanin. F. indologenes should be included as an etiologic agent of infections associated with the use of indwelling devices.     

Prevention of nosocomial infection in a pediatric intensive care unit (PICU) through the use of selective digestive decontamination

OBJECTIVE: To assess the effectiveness of selective digestive decontamination (SDD) on the control of nosocomial infection (NI) in critically ill pediatric patients. DESIGN: A prospective, randomized, non-blinded and controlled clinical microbiology study. SETTING: The pediatric intensive care unit (PICU) of a tertiary level pediatric university hospital. CRITERIA FOR INCLUSION: Patients 1 month to 14 years old, who underwent some kind of manipulation or instrumentation (mechanical ventilation, vascular cannulation, monitoring of intracranial pressure, thoracic or abdominal drainage, bladder catheterization, peritoneal dialysis, etc.) and/or presented a neurological coma requiring a stay in the PICU of 3 or more days. PATIENTS: Over a period of 2 years, 244 patients met the inclusion criteria; 18 patients were withdrawn because of protocol violation. The treatment group comprised 116 patients and the control group, 110 patients. INTERVENTION: The treatment group received a triple therapy of colimycin, tobramycin and nystatin administered orally or via nasogastric tube every 6 hours. All patients with mechanical ventilation or immune-depression received decontamination treatment of the oropharyngeal cavity with hexitidine (Oraldine 0.5 mg/ml) every 6-8 hours in accordance with the PICU's conventional protocol. METHOD: Up to 10 types of nosocomial infection were diagnosed following criteria of the Centers for Disease Control (CDC). The severity and manipulation of the patients on admission was assessed using the therapeutic intervention scoring system (TISS) and multi-organ system failure scores (MOSF). MEASUREMENTS AND MAIN RESULTS: UNIVARIANT ANALYSIS: SDD did not significantly reduce the incidence of NI, antibiotic use, the length of stay, or mortality; although a small percentage of respiratory and urinary tract infections was detected, catheter-related bacteremia was the most common infection. MULTIVARIANT ANALYSIS: Controlling the risk factors for each child through log regression showed that SDD acted as a protective factor for more than 90% of the sample with respect to the appearance of respiratory and urinary tract infections, reducing the risk of such infections to 1/5 and 1/3, respectively. CONCLUSIONS: SDD was effective in controlling respiratory and urinary tract infections in children admitted to the PICU, but it did not reduce the incidence of other types of nosocomial infection.     

Nosocomial infections in a neurosurgical intensive care unit

The occurrence of nosocomial infections in 1017 consecutive patients seen in a neurosurgical intensive care unit (ICU), over a period of 18 months is reported. The frequency of infections is low, which may possibly be due partly to the short stay in the ICU. Close interdisciplinary cooperation is stressed as an important factor in limiting infections. BACKGROUND. The aim of this study was to analyse the nosocomial infections in a neurosurgical intensive care unit over a period of 18 months, emphasizing localization and cause of infection, in order to adapt treatment and to take preventive measures. From 15% to 27% of patients treated in ICUs acquire nosocomial infections. In Germany this means 500,000-800,000 patients a year, and the annual costs related to nosocomial infections are estimated at 1.7 billion Deutschmarks. PATIENTS AND METHODS. In all, 1017 consecutive patients were evaluated. The patients were divided into two groups, depending on the duration of treatment in the ICU: Patients who remained for less than 48 h (1017 patients) Patients who were treated for a period exceeding 48 h (314 patients) The evaluation was performed retrospectively from the medical documentation. Criteria for registration are those of the Centers for Disease Control (Atlanta 1988). When more than one infection was diagnosed, each was considered as a new infection, regardless of the bacteria involved. Among the 314 patients who were in the ICU for more than 48 h a total of 114 nosocomial infections were recorded. The frequency of infection referred to all patients treated during that time (n = 1017) was 11.2%, while the frequency among those who were treated for longer than 48 h was 36.3%. Most infections (38.6%) affected the respiratory tract, followed by infections of the urinary tract. Of the bacteria determined 56.7% were gram-negative. In this group E. coli was the most frequently found (29.8%). In the group of gram-positive bacteria, S. aureus was diagnosed in 56.3% of cases. Twelve (16%) of the infected patients died and lethality referred to all patients was 8.6%. DISCUSSION. Compared with other studies, this study revealed a low the infection rate, at 11.2%. This can be explained partly by the short stay in this ICU (mean 3.7 days) and partly by the retrospective method of registration and the particular medical characteristics of neurosurgical patients. The well-known general risk factors for infection, such as age, mechanical ventilation, continuous catheterization of the bladder, and long duration of stay, are also found in neurosurgical ICUs. It is quite difficult to determine to what extent nosocomial infections prolong the treatment necessitated by the primary neurosurgical disease. We were not able to extrapolate the influence of immunosuppressant treatment on the appearance of nosocomial infections, as almost all patients in this study were receiving steroids. This study underlines the necessity of interdisciplinary cooperation between neurosurgeons, anaesthesiologists, microbiologists and nurses in neurosurgical ICUs, where most patients staying longer than 48 h are immunosuppressed and ventilated and thereby particularly at risk of nosocomial infections.     

Clinical significance of the isolation of rapidly growing mycobacteria

BACKGROUND: To assess the clinical significance of the isolates of rapid-growing mycobacteria in a Universitary hospital from Madrid (Spain). PATIENTS AND METHODS: Review of medical records from patients with isolates of rapid-growing mycobacteria identified between 1979 and 1996 in the Microbiology department of the Fundación Jiménèz Díaz (Madrid, Spain). RESULTS: Rapid-growing mycobacteria were isolated from 28 patients during the study period (13 M. chelonae, 10 M. fortuitum, 2 M. mucogenicum, 1 M. marinum, 1 M. smegmatis and 1 M. flavascens). Clinical records of 26 patients were reviewed, being the isolate significative in 10 cases (5 soft tissue infections, 2 peritonitis in patients undergoing Continuous Ambulatory Peritoneal Dialysis [CAPD], 1 urinary tract infection, 1 osteomyelitis and 1 catheter-related soft-tissue infection). No patient was HIV+. All infections cured except 2 of them (the urinary tract infection and the osteomyelitis). Catheter withdrawal was needed in 3 cases (peritonitis in CAPD and catheter-related soft-tissue infection), apart from proper antimicrobial therapy. CONCLUSION: The most frequent rapid-growing mycobacteria isolated were those of the M. fortuitum complex. In our experience, isolation of rapid-growing mycobacteria from skin and soft-tissue samples was usually clinically significant, while isolates from respiratory tract, gut and blood cultures are always nonsignificant.     

Intraoperative delayed pneumothorax after subclavian vein catheterization

Intraoperative delayed pneumothorax occurred in five patients. It took several attempts to insert a subclavian vein catheter in four of the patients. The first chest X-ray films after the insertion of the catheter in the five patients were not indicative of pneumothorax. Pulse oximetry could detect the initial sign of pneumothorax prior to hemodynamic instability in three patients. In case of positive pressure ventilation and nitrous oxide administration for general anesthesia, this complication may be life threatening. It is necessary to take great care not to overlook intraoperative delayed pneumothorax in a patient with subclavian vein catheterization.     

A potential pitfall in bronchial artery embolization

Two cases of patients with massive haemoptysis undergoing bronchial arteriography are described. Both had collateral vessels which filled the right subclavian artery from the right intercosto-bronchial trunk. Such vessels form a potential route for the passage of embolic material into the subclavian artery and its branches during therapeutic bronchial artery embolization. To avoid this potential complication, super selective catheterization with the positioning of the catheter tip well into the bronchial artery beyond the origin of the intercostal artery and any large collateral vessels is recommended.