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J Rello

Publications and source records attributed to J Rello.

At least 55 records · Page 3Linked to original sources
PubMed1997

Specific problems of arterial, Swan-Ganz, and hemodialysis catheters.

In our experience, the incidence and pathogenesis of colonization may vary in different types of catheters. Arterial, Swan-Ganz, and hemodialysis catheters are good examples of this problem. This observation has implications for diagnosis, and the best method for each type of catheter may not be the same. In our opinion, laboratory diagnosis in daily practice should be limited to external surface cultures of the tip of intravascular catheters. Intraluminal cultures should be limited to research purposes, except in catheters used for parenteral nutrition or hemodialysis. In this case, the intradermal segment gives more sensitive information. Sensitivity in diagnosing pulmonary artery colonization can be improved by evaluating both the tip and intradermal segments. In presence of an indwelling introducer the intradermal segment should be replaced by the introducer tip.

Catheterization, Peripheral↗
PubMed1997

Survival in patients with nosocomial pneumonia: impact of the severity of illness and the etiologic agent.

OBJECTIVE: To assess the impact of severity of illness at different times, using the Mortality Probability Models (MPM II), and the impact of etiologic agent on survival in patients with nosocomial pneumonia. DESIGN: Retrospective, observational study. SETTING: Fourteen-bed medical-surgical intensive care unit (ICU) in a teaching hospital. PATIENTS: Sixty-two patients with nosocomial pneumonia who were receiving early appropriate antibiotic treatment. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Severity of illness at the time of admission to the ICU (M0), 24 hrs after admission (M24), and at the time of pneumonia diagnosis (M1) was determined using MPM II. Bacteriology was established by quantitative cultures from bronchoscopic samples. The outcome measure was the crude mortality rate. The crude mortality rate in the ICU was 59.7%, compared with average predicted mortality rates of 43.5% (M0), 36.4% (M24), and 52.2% (M1). We observed significant differences in mean MPM II determinations between survivors and nonsurvivors at M1 (39.3% vs. 60.9%, p = .001) but not at M0 and M24. In the univariate analysis, the variables most predictive of mortality were the presence of coma (p = .02), inotropic medication use (p = .001), and an MPM II determination of > 50% (p = .001) when pneumonia was diagnosed (M1). Multivariate analysis showed that, in the absence of Pseudomonas aeruginosa, an MPM II determination of > 50% at M1 was associated with a relative risk of death of 4.8. The presence of P. aeruginosa was associated with an increase in the risk of death of 2.6 and 6.36 in both populations with MPM II determinations at M1 of < or = 50% and > 50%, respectively. CONCLUSIONS: Severity of illness when pneumonia is diagnosed is the most important predictor of survival, and this determination should be used for therapeutic and prognostic stratification. In addition, the presence of P. aeruginosa contributed to an excess of mortality that could not be measured by MPM II alone, suggesting the importance of the pathogen in prognosis.

Aged↗
PubMed1997

New perspectives in the diagnosis of nosocomial pneumonia.

In the past decade, much has been learned about the diagnosis of nosocomial pneumonia. Most of these reports focused on evaluating the diagnostic reliability of different techniques and identifying an adequate gold standard. In the past year, the most outstanding studies focused on practical issues such as developing more rapid and less invasive diagnostic techniques and tools, simplifying previously standardized techniques, and searching for safer and more cost-effective procedures. Following the current trend, in the next few years we should spend more time learning about the impact of current techniques on outcome and less time looking for "El Dorado."

Cross Infection↗
PubMed1997

Serial surveillance cultures of skin and catheter hub specimens from critically ill patients with central venous catheters: molecular epidemiology of infection and implications for clinical management and research.

A prospective study of 45 central venous catheters was conducted to assess, by strain delineation, the turnover of skin and catheter hub (superficial) colonization and the relative contributions of catheter hub and skin colonization to catheter tip colonization. Serial quantitative cultures of skin and catheter hub were performed. Catheter tip, blood, and specimens for culture from targeted superficial sites (TSSs) were also collected at the time of catheter removal. Strains from 17 tip-positive catheters were delineated by pulsed-field gel electrophoresis. Only 12 (28.6%) of 42 skin strains and 14 (31.1%) of 45 catheter hub strains were found to be present at the time of catheter removal. In addition, only 9 (29.0%) of the 31 tip-colonizing strains were present on TSSs. Moreover, 15 (48.4%) of the 31 tip-colonizing strains had a superficial origin, and the other 16 (51.6%) were of unknown origin. In catheters suspected of infection, cultures of TSSs had a negative predictive value for catheter-related bacteremia of 94.4% but a positive predictive value of 44.4%. When the causative agent was identified (to the strain level) these values dropped to 80.9 and 18.7%, respectively. The study shows that skin and catheter hub colonization is a common, dynamic phenomenon. Strains recovered from TSSs showed a low level of correlation with strains from previous cultures of specimens from superficial sites and catheter tip isolates. Consequently, TSSs cannot be recommended for use in determining the therapy. However, catheter-related bacteremia is uncommon when cultures of TSSs are negative.

Bacteria↗
PubMed1997

The value of routine microbial investigation in ventilator-associated pneumonia.

The use of microbiologic investigations in routine clinical practice, their value in guiding antibiotic prescription, and their influence on outcome were prospectively studied in 113 consecutive adults who developed ventilator-associated pneumonia (VAP). Blood cultures were performed in 78.7% of cases, protected specimen brushing in 95.5%, and bronchoalveolar lavage in only 45.1%. No causative agent was identified in 13 episodes (11.5%), and results of microbial tests directed a change in therapy in 43 (38.0%). Bronchoscopic results revealed inadequate initial selection of antibiotic therapy in 27 cases (23.9%) and led to a change in antibiotic treatment. Inadequate initial selection was still associated with a significantly greater increase in related mortality than adequate initial therapy (37.0% versus 15.4%, p < 0.05), although the change in therapy permitted clinical resolution in 17 (62.9%) of these 27 episodes, and 10 patients were discharged alive. Bronchoscopic results also permitted the reduction of the antibiotic spectrum in seven episodes (6.1%). This study suggests that in patients with VAP, bronchoscopic results are frequently associated with changes in antibiotic therapy. Nevertheless, our findings also emphasize the critical importance of an appropriate early antibiotic therapy.

Adult↗
PubMed1997

Risk factors for infection by Acinetobacter baumannii in intubated patients with nosocomial pneumonia.

STUDY OBJECTIVE: To investigate the epidemiology of infection by Acinetobacter baumannii in patients with ventilator-associated pneumonia (VAP). DESIGN: Prospective clinical study. SETTING: Three medical-surgical ICUs in teaching hospitals. PATIENTS: We followed up 707 mechanically ventilated patients and 148 episodes of VAP with etiologic diagnosis. RESULTS: A baumannii was isolated in 12 (8.1%) episodes in 148 patients. Five of these episodes were directly responsible for death. Using logistic regression analysis, the risk of VAP due to A baumannii was found to be high in patients with neurosurgery (odds ratio [OR]=10.03; 95% confidence interval [CI]=1.55 to 64.90), ARDS (OR=9.73; 95% CI=1.60 to 59.24), head trauma (OR=5.17; 95% CI=0.88 to 30.34), and large-volume pulmonary aspiration (OR=2.90; 95% CI=0.80 to 10.53). CONCLUSIONS: Intubated patients who develop pneumonia and have any of the above factors are at an increased risk of Acinetobacter infection.

Acinetobacter↗
PubMed1997

[Diagnosis of pneumonia in intubated patients: a controversy without resolution?].

There is yet no accurate, fast, innocuous and inexpensive method for the diagnosis of pneumonia associated to ventilation (NAV). Here we analyse three diagnostic lines of increasing level of certainty. CLINICA METHOD: Associates radiological image, pus in the trachea and temperature changes and or leukocytosis. Although it is quite sensitive in the absence of distress, is it not very specific. Nevertheless, it must be appreciated for its function as a guide, recalling that in its absence bacterial counts are of scarce value. QUANTITATIVE BACTERIOLOGICAL STUDIES OF DEEP SPECIMENS: Broncho-alveolar lavage (BAL) and protected brush (PB) serve a double objective: to discriminate colonisation from infection, and the identification of the etiological agent. The sensitivity of BAL/PB is approximately 70% while specificity is close to 80%. The method performs better in the absence of previous antibiotic therapy. HISTOLOGICAL DIAGNOSIS: Almost never obtained while the patient is alive, it is nevertheless the golden standard. The absolute diagnosis of NAV is: histological for pneumonia, with a positive tissue culture. USE OF DIAGNOSIS IN THERAPY: Empirical treatment results in a 40% failure rate. The specific treatment requires therapeutic changes in more than 1/3 of cases. Treatment when the micro-organism is known is followed by longer survival. Perhaps the correct approach would be: early empirical treatment after taking deep samples and correction according to the results obtained.

Bronchoalveolar Lavage Fluid↗
PubMed1996

Impact of using an indwelling introducer on diagnosis of Swan-Ganz pulmonary artery catheter colonization.

A prospective study was conducted to determine how the use of an indwelling introducer influences the diagnosis of pulmonary artery catheter (PAC) colonization. Sixty-six consecutive PACs and introducers were aseptically removed over a 15-month period. Two segments of the catheter and the catheter tip (a proximal segment from the portion of the catheter beneath the introducer) and two segments of the introducer (a proximal intradermal segment and the introducer tip) were cultured using a semiquantitative technique. Nineteen of 66 (28.7%) PACs showed colonization, representing an incidence of 5.6 episodes per 100 catheterization-days. Catheter tip cultures identified only 68% of colonized PACs; this yield rose to 91% when introducer tip cultures were added. These results indicate a need to evaluate both introducer tip cultures and catheter tip cultures for an accurate diagnosis of PAC colonization when an indwelling introducer is used.

Bacteria↗
PubMed1996

Antimicrobial use in patients with positive intravascular catheter cultures: a six-month prospective survey in a teaching hospital.

Review of medical records revealed that, of 190 intravascular catheters sent for culture during the study period, 50 were positive. Of these 50, 11 (22%) were sent for culture as a routine procedure without special clinical indications. Of the remaining 39 cultures, only 11 (28%) had clinical impact in the patient's management. Ten of the 50 therapeutic interventions were inappropriate. Restricting cultures to patients who may have catheter-related infection is likely to lead to significant cost savings.

Anti-Bacterial Agents↗
PubMed1996

Severe community-acquired pneumonia in the elderly: epidemiology and prognosis. Study Group for Severe Community-Acquired Pneumonia.

Ninety-five patients with severe community-acquired pneumonia (SCAP) who were > or = 65 years of age were studied prospectively. A definite pathogen was identified in 37 cases (38.9%) and was most commonly Streptococcus pneumoniae, Haemophilus influenzae, or another gram-negative bacillus. The overall death rate was 40%. Eighty-three patients required mechanical ventilation and 40 needed vasoactive drugs. Multivariate analysis showed that the risk of death was higher in cases involving rapid radiological spread (relative risk [RR] = 6.99; 95% confidence interval (95% CI) = 1.54-31.70), shock (RR = 6.70; 95% CI = 2.13-21.02), previous steroid treatment or immunosuppression (RR = 5.50; 95% CI = 0.77-39.10), acute renal failure (RR = 3.88; 95% CI = 1.30-11.59), or an APACHE II score of > 22 on admission (RR = 2.25; 95% CI = 0.73-6.95). We conclude that SCAP in elderly patients is associated with high mortality, but it is inappropriate to withhold intensive care on account of age. The presence of complications and the severity of illness at initial presentation were the major variables affecting outcome. Except for immunosuppression, comorbidities did not seem to influence outcome. Finally, our data reinforce the current American Thoracic Society guidelines concerning therapy for patients with SCAP.

Acute Kidney Injury↗
PubMed1996

Evaluation of outcome for intubated patients with pneumonia due to Pseudomonas aeruginosa.

Thirty consecutively intubated patients with pneumonia due to Pseudomonas aeruginosa (cases) were prospectively observed to establish the attributable mortality rate and the prognostic value of APACHE (Acute Physiological and Chronic Health Evaluation) II scores. Four cases did not receive accurate empirical therapy and were excluded from the study. APACHE II scores were calculated within 24 hours of admission (T0), at the time of the diagnosis of pneumonia (T1), and after 72 hours of therapy (T2). The outcomes for these cases (n = 26) were compared with those for matched controls (n = 52) without pneumonia. Six cases died of causes directly related to pneumonia (group D). Two cases whose conditions clinically improved died of cardiac complications, and 18 cases had clinical resolution (group R); however, only 15 of these cases were alive at discharge. The mean APACHE II score at admission was similar (P > .20) for group R, group D, and controls. In contrast, the mean score at T1 (15.40 +/- 6.07 vs. 20.83 +/- 4.66; P < .05) and the mean score at T2 (10.40 +/- 3.57 vs. 25.50 +/- 3.93; P < .01) differed significantly for groups R and D, respectively. The overall observed and predicted mortality rates among cases and controls were 42.3% and 28.1% and 28.8% and 28.7%, respectively, while the attributable mortality rate among cases was estimated to be 13.5% (95% confidence interval, 1.95%-25.04%). We conclude that the attributable mortality rate among intubated patients with pneumonia due to P. aeruginosa is high. The APACHE II score at admission is not useful as a prognostic factor, while progression of organ dysfunction after the onset of pneumonia is an ominous sign.

Adult↗
PubMed1996

A clinical trial on the prevention of catheter-related sepsis using a new hub model.

BACKGROUND: Catheter hub contamination is being increasingly recognized as a source of catheter-related sepsis. The authors have investigated the efficacy of a new hub design in preventing endoluminal catheter contamination and catheter-related sepsis arising at the hub. METHODS: Adult surgical and intensive care patients requiring a subclavian catheter for at least 1 week were randomly assigned to receive catheters with standard connectors (control group, n=73) or equipped with a new hub model (new hub group, n=78). Skin, catheter tip, and hub cultures were performed at the time the catheter was withdrawn because therapy was terminated or because of suspicion of sepsis, in which case peripheral blood cultures were taken. RESULTS: Of the 151 patients included, 15 (10%) developed catheter-related sepsis. Catheters were more often withdrawn because suspicion of infection in the control group (42 vs. 19%, p<0.005). Catheter sepsis rate was higher in the control group (16 vs. 4%, p<0.01) because of the low rate of catheter sepsis arising at the hub observed in the new hub group (1 vs. 11%, p<0.01). The prevalence of culture-positive catheter hubs without associated bacteremia (colonization) was higher in the control group (18 vs. 5%, P<0.03). CONCLUSIONS: A new catheter hub has proved to be useful in preventing endoluminal bacterial colonization and catheter-related sepsis in subclavian lines inserted for a mean of 2 weeks.

Adult↗
PubMed1996

Pneumonia in intubated patients: role of respiratory airway care.

In order to assess potential risk factors for pneumonia within the first 8 d of ventilation, we studied 83 consecutive intubated patients undergoing continuous aspiration of subglottic secretions (CASS). Multivariate analysis showed the protective effect of antibiotic use (relative risk [RR] = 0.10; 95% confidence interval [CI] = 0.01 to 0.71), whereas failure of the CASS technique (RR = 5.29; 95% CI = 1.24 to 22.64) was associated with a greater risk of pneumonia. In addition, there was a trend toward a higher risk of pneumonia (RR = 2.57; 95% CI = 0.78 to 8.03) among patients with persistent intracuff pressures below 20 cm H2O. The remaining factors analyzed were not significant. Failure of CASS did not influence the development of pneumonia among patients undergoing antibiotic treatment (33.0% versus 38.5%, p > 0.20), but was strongly associated with pneumonia (42.1% versus 8.3%, p < 0.01) among intubated patients not receiving antibiotics. When multivariate analysis was repeated in this subpopulation, failure of CASS (RR = 7.52, 95% CI = 1.48 to 38.07) and persistent intracuff pressure below 20 cm H2O (RR = 4.23, 95% CI = 1.12 to 15.92) were factors independently associated with the development of pneumonia. We conclude that leakage of colonized subglottic secretions around the cuff of the endotracheal tube is the most important risk factor for pneumonia within the first 8 d of intubation. This study confirms the importance of maintaining adequate intracuff pressure and effective aspiration of subglottic secretions in preventing pneumonia in intubated patients not receiving antibiotic treatment.

Antibiotic Prophylaxis↗
PubMed1996

Microbial causes of ventilator-associated pneumonia.

Aspiration of microorganisms colonizing the oropharynx is the main route of bacterial entry to lower airways in mechanically ventilated patients. Examination of the microbial flora involved in ventilator-associated pneumonia shows that only few species, among the many oropharynx microorganisms, are responsible for the majority of lower respiratory tract colonizations and infections in intubated patients. Underlying disease, length of intubation, and type and duration of prior antibiotic therapy are the most important factors related with the causative flora of respiratory infections in these patients. Except in certain populations (eg, chronic obstructive pulmonary disease [COPD] patients who may be colonized by Pseudomonas aeruginosa), methicillin-sensitive Staphylococcus aureus, Streptococcus pneumoniae, and unencapsulated Hemophilus influenzae are the predominant respiratory pathogens within the first week of intubation in critically ill patients. These microorganisms are subsequently replaced by multiresistant flora, such as Pseudomonas aeruginosa, methicillin-resistant staphylococci or Acinetobacter baumanii. This change of flora takes place as a consequence of prior antibiotic therapy among other factors. Fungi have to be taken in account particularly in the presence of severe immunodepression. All of these multiresistant pathogens (particularly P aeruginosa) are responsible for most of the deaths directly related to pneumonia; therefore, the early recognition of causative agents and appropriate antibiotic therapy are of great importance determining outcome. This strategy represents the most efficient approach to managing patients with ventilator-associated pneumonia.

Anti-Bacterial Agents↗
PubMed1995

Continuous aspiration of subglottic secretions in preventing ventilator-associated pneumonia.

OBJECTIVE: To determine whether continuous subglottic aspiration prevents nosocomial pneumonia in mechanically ventilated patients. DESIGN: A randomized, controlled, blinded study. SETTING: Medical-surgical intensive care unit. PATIENTS: 190 patients who were admitted to the intensive care unit during a 33-month period and whose condition suggested the need for prolonged intubation (> 3 days). INTERVENTION: 76 patients were randomly allocated to receive continuous aspiration of subglottic secretions, and 77 control patients were allocated to receive usual care. MEASUREMENTS: The numbers of cases of ventilator-associated pneumonia, ventilated days, days in intensive care unit, and deaths were recorded. The amount of subglottic secretions aspirated daily and surveillance cultures in the subglottic secretions were also obtained periodically. Etiologic diagnosis was based on the quantitative culture of secretions obtained by protected specimen brush or bronchoalveolar lavage. RESULTS: The incidence rate of ventilator-associated pneumonia was 19.9 episodes/1000 ventilator days in the patients receiving continuous aspiration of subglottic secretions and 39.6 episodes/1000 ventilator days in the control patients (relative risk, 1.98; 95% CI, 1.03 to 3.82). This difference was due to a significant (P < 0.03) reduction in the number of gram-positive cocci and Haemophilus influenzae organisms in the patients receiving continuous aspiration. However, no differences were observed in the number of Pseudomonas aeruginosa or Enterobacteriaceae organisms. Episodes of ventilator-associated pneumonia occurred later in patients receiving continuous aspiration (12.0 +/- 7.1 days) than in the control patients (5.9 +/- 2.1 days) (P = 0.003). The same microorganisms isolated from protected specimen brush or bronchoalveolar lavage cultures in patients with ventilator-associated pneumonia were previously isolated from cultures of subglottic secretions in 85% of cases. No significant differences in outcome were found. CONCLUSIONS: The incidence of nosocomial pneumonia in mechanically ventilated patients can be significantly reduced by using a simple method that decreases the chronic microaspirations through the cuff of endotracheal tubes.

Aged↗