Antimicrobial therapy for intra-abdominal infections: guidelines from the Infectious Disease Advisory Board (IDAB).

Intra-abdominal infection is a common cause of severe sepsis in a hospital setting and remains associated with a significant morbidity, mortality and resource use. Early adequate surgery or drainage remain the cornerstones of intra-abdominal infection management and impact on patients outcome. Concomitant early and adequate empiric antimicrobial therapy further influences patients morbidity and mortality. Multiple empirical regimens have been proposed in this setting, but rarely supported by well designed, randomized-controlled studies. The current manuscript summarizes the recommendations of the Infection Disease Advisory Board on the management of intra-abdominal infections. Empiric antimicrobial therapy for the most common causes of abdominal infections is proposed. In addition, particular attention has been paid on antibiotic treatment duration.

Ventilator-associated pneumonia in a tertiary care ICU: analysis of risk factors for acquisition and mortality.

OBJECTIVE: To investigate the incidence, risk factors and mortality of ventilator-associated pneumonia (VAP) in intensive care unit (ICU) patients. DESIGN: Prospective, observational, population-based study. SETTING: The medical (14-bed) and surgical ICU (26-bed) of the Ghent University Hospital. METHODS: All 1295 patients admitted to the ICU during 4 three-month periods between 1996 and 1998 were included. A set of demographic and clinical variables were collected at the day of admission and during the ICU course. RESULTS: The incidence of VAP among ICU patients ventilated at least 48 hours was 23.1%. The mean time to the development of VAP was 9.6 days with a median of 6 days. In the population of patients ventilated for at least 48 hours, a comparison was made between patients with (n = 89) and without VAP (n = 296). Patients with VAP had a significant longer ICU stay, with a longer ventilation dependency. Logistic regression analysis identified admission diagnosis other than trauma (OR: 0.51, 95% CI: 0.29-0.89; p = 0.02) and the length of ICU stay (OR: 1.05, 95% CI: 1.03-1.07; p < 0.001) to be independently associated with the acquisiton of VAP. In comparison with the total study population, patients with VAP had a higher ICU mortality (20.2% vs. 12.0%; p = 0.04), but not in the cohort group of patients at risk for VAP (ventilated > 48 hours)(20.2% vs. 31.3%; p = 0.03). The factors independently associated with death were higher SAPS II scores (OR 1.02, 95% CI: 1.003-1.032; p = 0.02), an admission diagnosis other than trauma (OR 0.36, 95% CI: 0.17-0.75; p = 0.006) and length of ICU stay (OR 0.97, 95% CI: 0.946-0.995; p = 0.02). This model did not recognize VAP as an independent predictor of death (OR 0.79, 95% CI: 0.41-1.53; p = 0.492). CONCLUSIONS: The incidence of VAP in our ICU is 23.1%. Length of ICU stay and an admission diagnosis other than trauma are major risk factors for the development of this nosocomial infection. VAP is associated with a high fatality rate. However, after adjustment for disease severity and length of ICU stay, VAP was not identified as an independent predictor of death.

Appropriate and timely empirical antimicrobial treatment of icu infections--a role for carbapenems.

Treatment of serious nosocomial infections in the intensive care unit requires swift, effective, well-tolerated and appropriate therapy from the outset. The consequences of inappropriate treatment, i.e. the use of antibiotics that are ineffective against the causative pathogen(s) or delayed therapy, are numerous and impact negatively upon both the patient and the ever-dwindling healthcare resources in many hospitals. Although antibiotics have revolutionised the treatment of infections, their inappropriate and untimely use within the intensive care setting has led to the emergence and spread of antibiotic-resistant bacteria worldwide. Consequently, to ensure successful patient outcomes (reduce morbidity and mortality), it is important that any antibiotic treatment employed is right first time. Treatment of serious infections in the intensive care unit requires an empirical stratagem providing broad-spectrum coverage to a wide range of suspected or difficult-to-treat pathogens such as Pseudomonas aeruginosa. However, to prevent the errors of the past, this needs to be tailored as soon as the pathogen has been identified and resistance patterns are known. The carbapenems are potent parenteral antibiotics, with an ultra-broad spectrum of activity that encompasses multi-drug resistant and difficult-to-treat Gram-negative bacteria. Clinical trial data supports the clinical effectiveness of these agents in patients with difficult to treat pathogens.

Temporal scanner thermometry: a new method of core temperature estimation in ICU patients.

BACKGROUND AND AIMS: Temperature measurement is a routine task of patient care, with considerable clinical impact, especially in the ICU. This study was conducted to evaluate the accuracy and variability of the Temporal Artery Thermometer (TAT) in ICU-patients. Therefore, a convenience sample of 57 adult patients, with indwelling pulmonary artery catheters (PAC) in a 40-bed intensive care unit in a university teaching hospital was used. METHODS: The study design was a prospective, descriptive comparative analysis. Body temperature was thereby measured simultaneously with the TAT and the Axillary Thermometer (AT), and was compared with the temperature recording of the PAC. The use of vasoactive medication was recorded. RESULTS AND CONCLUSIONS: Mean temperature of all measurements was: PAC: 37.1 degrees C (SD: 0.87), TAT 37.0 degrees C (SD: 0.68) and axillary thermometer: 36.6 degrees C (SD: 0.94). The measurements of the TAT and the PAC were not significantly different (man differnce: 0.14 degrees C; SD: 0.51; p = 0.33); whereas the measurements of the PAC and the AT differed significantly (mean difference: 0.46 degerees C; SD: 0.39; p < 0.001). Mean diference in PAC versus TAT analyses, between patients with vasopressor therapy (0.12 degrees C; SD: 0.55), and without vasopressor therapy (0.19 degrees C; SD: 0.48) was not statistically significant (p = 0.47). CONCLUSION: We can conclude that the temporal scanner has a relatively good reliability with an acceptable accuracy and variability in patients with normothermia. The results are comparable to those of the AT, but they do not seem to be sufficient to prove any substantial benefit compared to rectal, oral or bladder thermometry.

Infectious complications of acute pancreatitis.

Disease severity in patients with acute pancreatitis varies from mild disease with minimal morbidity, to severe disease in which a whole spectrum of local and systemic complications may occur. Infectious complications frequently arise, and especially infection of pancreatic necrosis is an important risk factor for mortality. Several strategies have been devised to reduce this risk, and the use of prophylactic therapy, e.g. selective digestive decontamination, can be considered in patients with documented necrosis fo the pancreas. Pancreatic abscesses and infected pseudocysts arise later in the course of disease, and should be considered as separate entities, due to differences in therapy and outcome of these patients. When infection occurs, source control using either surgical or percutaneous drainage techniques, is essential to avoid systemic complications.

Invasive aspergillosis in critically ill patients: attributable mortality and excesses in length of ICU stay and ventilator dependence.

Invasive aspergillosis is a rare disease in intensive care unit (ICU) patients and carries a poor prognosis. The aim of the present study was to determine the attributable mortality due to invasive aspergillosis in critically ill patients. In a retrospective, matched cohort study (July 1997-December 1999), 37 ICU patients with invasive aspergillosis were identified together with 74 control patients. Matching of control (1:2) patients was based on the acute physiology and chronic health evaluation (APACHE) II classification: an equal APACHE II score (+/-1 point) and diagnostic category. This matching procedure results in an equal expected in-hospital mortality for cases and controls. Additionally, control patients were required to have an ICU stay equivalent to or longer than the case before the first culture positive for Aspergillus spp. Patients with invasive aspergillosis were more likely to experience acute renal failure (43.2% versus 20.5%; P = 0.020). They also had a longer ICU stay (median: 13 days versus seven days; P < 0.001) as well as a more extended period of mechanical ventilator dependency (median: 13 days versus four days; P < 0.001). Hospital mortalities for cases and controls were 75.7% versus 56.8%, respectively (P=0.051). The attributable mortality was 18.9% (95% CI: 1.1-36.7). A multivariate survival analysis showed invasive aspergillosis [hazard ratio (HR): 1.9, 95% CI: 1.2-3.0; P = 0.004] and acute respiratory failure (HR: 6.5, 95%: 1.4-29.3; P < 0.016) to be independently associated with in-hospital mortality. In conclusion, it was found that invasive aspergillosis in ICU patients carries a significant attributable mortality of 18.9%. In a multivariate analysis, adjusting for other co-morbidity factors, invasive aspergillosis was recognized as an independent predictor of mortality.

Bloodstream infections after surgery for severe acute pancreatitis.

OBJECTIVE: To analyze the incidence and outcome of bloodstream infections (BSIs) in patients operated on for severe acute pancreatitis to identify the source and associated risk factors. METHODS: We retrospectively (1995-2001) analyzed 45 patients treated surgically for severe acute pancreatitis. We recorded demographic characteristics, data on surgical and medical treatment and disease severity, the occurrence of BSIs, microbiological data concerning the BSIs and other infectious processes, the incidence of organ failure, and data on surgical and infectious complications. RESULTS: Fifteen episodes of BSI were found in 7 of 45 patients (15%), with 18 organisms involved. In all but 1 episode, the source of the BSI was pancreatic necrosis. Most of the organisms were gram positive (11); the others were gram negative (6) or fungi (1). Mortality was statistically not different in patients with a BSI (57% vs. 35%). Multivariate analysis demonstrated that only the length of intensive care unit (ICU) stay was associated with the occurrence of BSIs (OR, 1.05; 95% CI, 1.02-1.09; P < 0.01). CONCLUSION: A BSI is not a rare finding after surgery for severe acute pancreatitis, especially in patients with a prolonged ICU stay. The source is the infected necrosis in most of BSI episodes.

Invasive aspergillosis in critically ill patients: analysis of risk factors for acquisition and mortality.

OBJECTIVE: To investigate outcome in patients who develop invasive aspergillosis in the ICU, and to evaluate whether specific risk factors for the acquisition of invasive aspergillosis are associated with mortality. DESIGN: Retrospective cohort study (07/1997-12/1999) with screening of 8988 admissions. SETTING: 54-bed ICU of the 1060-bed Ghent University Hospital. PATIENTS: 38 ICU patients with invasive aspergillosis. Invasive aspergillosis was defined as proven by positive histology and tissue culture and as probable by a combination of clinical suspicion as well as microbiological and radiological data. Seventeen patients had risk factors (neutropenia, haematological malignancy, immunosuppressive therapy). In the other 21 apparently immunocompetent patients, invasive aspergillosis was a complication following ARDS, COPD, pneumonia, acute liver failure, burns, severe bacterial infection and malnutrition. MEASUREMENTS: Population characteristics and outcome were compared for patients with and without risk factors for the acquisition of invasive aspergillosis. RESULTS: Patients with risk factors had higher APACHE II scores. No difference was found between patients with and without risk factors in in-hospital mortality (82% vs. 71%; p=0.431). In patients with specific risk factors, the observed mortality was not different from the mortality as expected on basis of the APACHE II (p=0.940). In patients without risk factors the observed mortality exceeded the expected mortality (p<0.001). CONCLUSION: The incidence of invasive aspergillosis in this series is 4/1000 admissions. No difference in mortality was found between patients with and without risk factors for the acquisition of invasive aspergillosis. Yet, the prognosis of the patients without risk factors seems to alter more seriously by the development of this infection.

Adrenal insufficiency in severe acute pancreatitis.

Relative adrenal insufficiency is common in patients with severe sepsis and septic shock. We describe three patients with severe acute pancreatitis who developed signs suggestive of adrenal insufficiency during the early phase of the disease. Clinical features and possible causes of adrenal insufficiency are discussed.

Fungal infections in patients with severe acute pancreatitis and the use of prophylactic therapy.

Data from an 8-year period for 46 patients with severe acute pancreatitis and infected pancreatic necrosis were analyzed to determine the incidence of fungal infection, to identify risk factors for the development of fungal infection, and to assess the use of early fluconazole treatment. Intraabdominal fungal infection was found in 17 (37%) of 46 patients. Candida albicans was isolated most frequently (15 patients); Candida tropicalis and Candida krusei were found in 1 patient each. Characteristics of patients with fungal infection were not different from patients without fungal infection. The difference in mortality was not statistically significant between patients with fungal infection and patients without fungal infection. Early antifungal therapy (prophylactic or preemptive antifungal therapy) was administered to 18 patients, and only 3 of them developed fungal infection. In this cohort of critically ill patients, no risk factors for fungal infection could be demonstrated, and mortality among patients who received early antifungal therapy was not different. Early treatment with fluconazole seems to prevent fungal infection in these high-risk patients.

Reappraisal of attributable mortality in critically ill patients with nosocomial bacteraemia involving Pseudomonas aeruginosa.

In a retrospective study, population characteristics and outcome were investigated in intensive care unit (ICU) patients with hospital-acquired Pseudomonas aeruginosa bacteraemia admitted over a seven-year period (January 1992 through December 1998). A matched cohort study was performed in which all ICU patients with P. aeruginosa bacteraemia were defined as cases (N=53). Matching (1:2 ratio) of the controls (N=106) was based on the APACHE II classification: an equal APACHE II score (+/-1 point) and an equal diagnostic category. Patients with P. aeruginosa bacteraemia had a higher incidence of acute respiratory failure, haemodynamic instability, a longer ICU stay and length of ventilator dependence (P<0.05). In-hospital mortalities for cases and controls were 62.3 vs. 47.2% respectively (P=0.073). Thus, the attributable mortality was 15.1% (95% confidence intervals: -1.0-31.2). In a multivariate survival analysis the APACHE II score was the only variable independently associated with mortality. In conclusion, P. aeruginosa bacteraemia is associated with a clinically relevant attributable mortality (15%). However, we could not find statistical evidence of P. aeruginosa being an independent predictor of mortality.

The effect of tube thoracostomy on oxygenation in ICU patients.

Previous research found that in noncritically ill patients, thoracocentesis has an unpredictable effect on oxygenation, possibly due to re-expansion pulmonary edema and systemic hypotension. The authors performed a retrospective analysis to study the effect of tube thoracostomy on oxygenation in ICU patients, and the complications associated with it. The authors reviewed the charts of 58 ICU patients in whom 74 procedures were performed. Demographic data, APACHE II score, and indication for thoracocentesis were retrieved from the patient's file. The P(a)O(2)/FiO(2) ratio was calculated before, 12, 24, and 48 hours after tube thoracostomy. P(a)O(2)/FiO(2) ratios at the mentioned time intervals were compared using 1-way analysis of variances (ANOVA) with repeated measures. Logistic regression analysis was used to identify factors associated with a good response to treatment. Age of the patients was 53 +/- 19.0 years (range, 17-88), APACHE II score was 21 +/- 8.3 (range, 6-38), and median length of stay was 13.5 days (interquartile range, 7-25). The volume drained during the first 24 hours was 1077 +/- 667 ml. P(a)O(2)/FiO(2) ratio was 185 +/- 79.3 before chest drainage, 197 +/- 79.1 at 12 hours, 217 +/- 88.9 at 24 hours, and 233 +/- 99.8 at 48 hours. In only 54% of the procedures, a response to therapy was present. Multivariate analysis identified a P(a)O(2)/FiO(2) below 180 to be independently associated with improvement in oxygenation. At 24 and 48 hours, the P(a)O(2)/FiO(2) ratio was significantly higher than before drainage (P <.001). There were 13 complications in 11 procedures (14.9%). The authors' results suggest that tube thoracostomy can be used as an adjunct in the treatment of selected patients with hypoxemic respiratory failure in the ICU. A low P(a)O(2)/FiO(2) seems to be a good predictor of response to therapy. However, the complication rate is considerable, especially in patients with a prolonged ICU stay.

Evaluation of human albumin use in a university hospital in Belgium.

UNLABELLED: In 1996-1997, a drug use evaluation (DUE) of human albumin was conducted in the Ghent University Hospital (Belgium) to determine the pattern and appropriateness of the albumin use. The DUE was followed by permanent review of the albumin consumption. This paper describes how the DUE was carried out and how the albumin use in our hospital changed over time. METHOD: The study was based on criteria for indications and end of treatment, accepted by consensus of the physicians prescribing albumin. Albumin treatment episodes were classified as appropriate or inappropriate according to these criteria. RESULTS: For 115 treatment episodes in 90 patients, the researchers found 21 (18.3%) deviations from the developed criteria. After analysis, half out of them were considered as minor. Most deviations involved starting treatment too early (n = 17). Follow-up results indicated that the overall consumption of albumin dropped by 50.1% from 1994 to 1999, while the consumption of colloid solutions during the same period remained stable. CONCLUSION: A good compliance with internally developed criteria for indications and end of treatment with human albumin was observed. Discussion with the clinicians involved led to the development of stricter criteria and a continuous decrease in albumin consumption.

Clinical impact of nosocomial Klebsiella bacteremia in critically ill patients.

In order to determine the clinical impact of Klebsiella bacteremia on critically ill patients, a matched cohort study was conducted between January 1992 and December 2000. During the study period, all intensive care unit (ICU) patients with nosocomial Klebsiella bacteremia were defined as cases (n=52), but two of these patients were excluded from the matched cohort due to incomplete medical records. The remaining 50 patients were matched at a ratio of 1:2 with control patients (n=100) on the basis of the APACHE II severity of disease classification system. Patients with Klebsiella bacteremia experienced acute renal failure and hemodynamic instability more often than controls. They also had a longer ICU stay and longer ventilator dependence. In-hospital mortality rates for cases and controls were nearly equal (36% vs. 37%, respectively; P=0.905). In conclusion, after adjusting accurately for severity of underlying disease and acute illness, no difference in mortality was found between ICU patients with Klebsiella bacteremia and their matched control subjects.

Outcome in critically ill patients with candidal fungaemia: Candida albicans vs. Candida glabrata.

In a retrospective study (1 January 1992-12 December 1998), we investigated population characteristics and outcome in critically ill patients with fungaemia involving C. albicans (n=41) and C. glabrata (n=15). Patients with C. glabrata fungaemia were significantly older compared with patients in the C. albicans group (P=0.024). There were no other differences in population characteristics or severity of illness. Logistic regression analysis showed age (P=0.021), the presence of a polymicrobial blood stream infection (P=0.039), and renal failure (P=0.044) to be independent predictors of mortality. There was no significant difference in in-hospital mortality between the C. glabrata and C. albicans groups (60.0% vs. 41.5%; P=0.24). Since age was an independent predictor of mortality, the trend towards a higher mortality in patients with C. glabrata can be explained by this population being significantly older. In conclusion, we found no difference in mortality between patients with fungaemia involving C. albicans and C. glabrata.

Course of neuropsychological recovery from moderate-to-severe head injury: a 2-year follow-up.

Neuropsychological outcome and recovery of a group of 91 patients with moderate-to-severe head injuries were prospectively investigated over a 2 year period, with evaluations at acute hospital discharge at 6 months and 2 years post-injury. A group of 39 trauma patients with injuries to parts of the body other than the head were used as controls. The head injured group performed significantly worse than the control group at baseline, 6 months and 2 years post-injury. Significant improvement was found during the first 6 months, but also between 6 months and 2 years post-injury. Trauma controls also performed significantly better at 6 months post-injury compared to baseline. Differential practice effects between groups cause difficulties in determining recovery. Within the head injured group, three distinct recovery groups were identified varying as a function of coma-length and coma-duration. The first group is comparable with the trauma controls. The other two groups demonstrate significant neuropsychological impairments at baseline, with one group showing a marked improvement over the 2 year period, and the other group showing only small improvement over this time period.

Prevalence and risk factors for colonisation with gram-negative bacteria in an intensive care unit.

OBJECTIVE: To investigate prevalence and determine risk factors for colonisation with Gram-negative bacteria in ICU patients. DESIGN: Prospective, surveillance study. SETTING: 26-bed surgical and paediatric ICU. PATIENTS: 159 patients--whereof 22 infants--admitted to the surgical/paediatric ICU over a two-month period. INTERVENTION: In all patients routine microbiological monitoring was performed by thrice weekly oral swabs, urine sampling and, additionally, tracheal aspirates in patients on mechanical ventilation (MV) and by anal swabs once weekly. RESULTS: Population characteristics: Mean age of the adult population was 51.1 +/- 17.6 year. Mean age of the paediatric population was 6.3 +/- 5.3 year. The mean APACHE II-score was 18 +/- 9.1. The mean PRISM-score was 9.7 +/- 5.4. The mean ICU stay was 7.5 +/- 11.4 days. 43.4 percent of patients received mechanical ventilation (MV). The mean number of mechanical ventilation days was 11.1 +/- 14.7 days. 32.1% of patients experienced colonisation with Gram-negative bacteria. Prevalence of colonisation increased with length of ICU stay. The probability of colonisation was 24% after an ICU stay of 3 days (= median ICU stay). Time to colonisation was not different between the controlled sites (p > 0.05). 47% of colonizations were due to multiresistant strains. Higher APACHE II-scores and MV were associated with a higher prevalence of colonisation (p < 0.01). The ICU mortality was 8% among adult and 4% among paediatric patients. CONCLUSION: Patients with high APACHE II-scores, on mechanical ventilation and with an ICU stay of more than 3 days are most at risk for colonisation with Gram-negative bacteria. These patients should be cared with the optimal precautions in the prevention of colonisation and infection.