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B Guery

Publications and source records attributed to B Guery.

36 records · Page 2Linked to original sources
PubMed1999

Simplified prediction rule for prognosis of patients with severe community-acquired pneumonia in ICUs.

STUDY OBJECTIVES: To develop a simplified prognostic prediction rule for patients admitted to ICUs for severe community-acquired pneumonia (CAP). SETTING: Six ICUs in the north of France. PATIENTS: Five hundred five patients admitted to ICUs over a 9-year period (from 1987 to 1995) for severe CAP. INTERVENTIONS: Retrospective prognosis analysis and multivariate analysis using a credit scoring technique. MEASUREMENTS: The primary outcome measure was ICU mortality. RESULTS: Among the 505 patients, 472 were eligible for the prognosis study. The ICU mortality rate was 22.9%. Multivariate analysis identified, on the basis of the patient's medical history and initial examination on ICU admission, six independent predictors of mortality: age > or = 40 years, anticipated death within 5 years, nonaspiration pneumonia, chest radiograph involvement > 1 lobe, acute respiratory failure requiring mechanical ventilation, and septic shock. An initial risk score based on these factors classified patients into three risk classes of increasing mortality: 4% in class I, 25% in class II, and 60% in class III. Multivariate analysis of events occurring during ICU stay identified three independent predictors of mortality: hospital-acquired lower respiratory tract superinfections, nonspecific CAP-related complications, and sepsis-related complications. An adjustment risk score based on these factors was essential to accurately predict the final outcome of patients in the initial risk class II. CONCLUSIONS: As an aid to clinicians in stratifying the prognosis of patients with severe CAP, the simplified prediction rule used in this study could be useful for therapeutic decisions and appropriate care.

Community-Acquired Infections↗
PubMed1999

In vivo application of intestinal pH measurement using 2',7'-bis(carboxyethyl)-5,6-carboxyfluorescein (BCECF) fluorescence imaging.

Measurement of gastrointestinal intramucosal pH (pHim) has been recognized as an important factor in the detection of hypoxia-induced dysfunctions. However, current pH measurement techniques are limited in terms of time and spatial resolutions. A major advance in accurate pH measurement was the development of the ratiometric fluorescent indicator dye, 2',7'-bis(carboxyethyl)-5,6-carboxyfluorescein (BCECF). This study aimed to set up and validate a fluorescence imaging technique to measure in vivo the intramucosal pH (pHim) of the intestine. The intestine was inserted into an optical chamber placed under a microscope. Animals were injected intravenously with the pH-sensitive fluorescent dye BCECF. Fluorescence was visualized by illuminating the intestine alternately at 490 and 470 nm. The emitted fluorescence was directed to an intensified camera. The ratio of emitted fluorescence at excitation wavelengths of 490 and 470 nm was measured, corrected and converted to pHim by constructing a calibration curve. The pHim controls were performed with a pH microelectrode and were correlated with venous blood gas sampling. Results show that pHim is determined with an accuracy of +/- 0.07 pH units and a response time of 1 min. In conclusion pHim mapping of rat intestine can be obtained by fluorescence imaging using BCECF. This technology could be easily adapted for endoscopic pH measurements.

Animals↗
PubMed1998

[Evaluation of prescription of antibiotics in an intensive care unit].

OBJECTIVES: In order to optimize prescriptions, we conducted a qualitative evaluation of antibiotic prescription in an intensive care unit. METHODS: A prospective observational study was performed on 100 consecutive prescriptions from 11/95 to 4/96. RESULTS: Among 14 documented cases, initial antibiotic therapy was in accordance with antimicrobial susceptibility patterns in all but one case. Among 86 empirical cases, 38 were secondarily documented, yielding 43 microorganisms. Of these 38, 27 were susceptible to 2 or more empirical antibiotics, 3 to only 1 and 8 to none. Antibiotics were modified in 23/38 (60%) cases, resulting in drug changes (n = 21) or drug addition (n = 2). In all cases, the new prescription was consistent with the antibiogram. In the 48 cases where no microorganism was isolated, antibiotic change was guided by clinical course and occurred in 6 (12.5%) cases. A switch to older, cheaper or more narrow spectrum antibiotics was possible in 18 cases, but was actually done in only 4 (22%). Dosage errors were observed in 5 cases of initial therapy. Second line therapy contained 8(21%) dosage errors. Most frequently, isolated organisms at admission were: Staphylococcus sp. (n = 15), P. aeruginosa (n = 11) and S. pneumoniae (n = 10). New pathogens emerged in 16 patients (16%) receiving antibiotics. The most frequent was P. aeruginosa in 4 patients receiving ofloxacin + amoxicillin +/- clavulanic acid. CONCLUSION: These results are encouraging, however, the use of guidelines and periodic evaluation of antibiotic prescription practices might improve the efficiency of empirical antibiotic prescriptions and reduce overall antibiotic costs.

Anti-Bacterial Agents↗
PubMed1998

Prevalence of drugs of abuse in urine of drivers involved in road accidents in France: a collaborative study.

The collaborative, anonymous, case-control study was intended to determine the prevalence of opiates, cocaine metabolites, cannabinoids and amphetamines in the urine of drivers injured in road accidents and to compare these values with those of non-accident subjects ("patients") in France. Recruitment was performed nationwide in the emergency departments of five hospitals and comprised 296 "drivers" aged 18 to 35 and 278 non-traumatic "patients" in the same age range. Females represented 28.4% of "drivers" and 44.2% of "patients." Screening for drugs in urine was performed by fluorescence polarization immunoassays in each center. Each positive result was verified using gas chromatography-mass spectrometry (GC-MS), in a single laboratory. Statistical analysis comprised single-step logistic regression and simultaneously took account of confounding factors and the final differences in prevalence values between the two populations or different subgroups. Cannabinoids were found in 13.9% of drivers (16.0% of males and 8.3% of females, p < 0.05) and 7.5% of patients (12.3% of males, 1.6% of females, p < 0.0001); only in females was this prevalence higher in injured drivers than in patients (p < 0.05). Opiates were present in 10.5% of drivers' and 10.4% of patients' urine samples (NS), and were more frequent in urine samples positive for cannabinoids, in drivers (p < 0.01) as well as in patients (p < 0.001). The prevalence of cocaine metabolites in drivers and patients was 1.0 and 1.1% and that of amphetamines 1.4 and 2.5%, respectively. No causal relationship between drugs and accidents should be inferred from this retrospective study. Nevertheless, the high prevalence of cannabis and opiate (licit or illicit) use in young people, whether injured drivers or patients, has potential implications for road traffic safety in France. Cocaine and amphetamines did not appear to be a major problem, unlike the experience in other countries.

Accidents, Traffic↗
PubMed1997

Pulmonary disposition of vancomycin in critically ill patients.

Vancomycin penetration in epithelium lining fluid was studied in ten mechanically ventilated patients with methicillin-resistant Staphylococcus aureus pneumonia 24 hours after the onset of treatment. Vancomycin was given intravenously at a daily dose of 30 mg/kg. Vancomycin levels were detectable in four patients (range, 1-2.77 micrograms/ml). Concordance between high plasma concentrations (> 20 micrograms/ml) and detectable vancomycin levels in epithelium lining fluid was noted. These results suggest that the pulmonary disposition of vancomycin remains low for most patients 24 h after the onset of treatment compared with the minimum inhibitory concentrations for most gram-positive organisms. One therapeutic goal of vancomycin treatment could be to obtain through plasma levels of 20 micrograms/ml. Further studies are required to determine the clinical relevance of these observations.

Aged↗
PubMed1997

Community-acquired aspiration pneumonia in intensive care units. Epidemiological and prognosis data.

Over a 9-yr period, among 505 patients exhibiting severe community-acquired pneumonia and admitted into a total of six medical ICUs in the north of France, we collected 116 patients (23%) meeting the usual criteria for aspiration pneumonia. Main medical grounds of ICU admission were respiratory distress in 54 patients and neurological disturbances in 62 patients. The main underlying risk factor for aspiration pneumonia was drug overdose (39%). Mechanical ventilation was required for 73 patients. Initial shock was present in 15 patients. Pulmonary involvement was bilateral in 27 patients. There were 94 aerobic organisms isolated from 70 patients (60%), the most frequent being gram-negative bacilli (n = 38), Staphyloccus spp. (n = 27) and Streptococcus pneumoniae (n = 22). Overall mortality was 22%, but only 11 (11%) deaths were directly or indirectly related to aspiration pneumonia. Stepwise multivariate analysis identified four independent predictors of mortality: ineffective initial antimicrobial therapy (p = 0.0001), positive initial blood culture (p = 0.0001), hospital-acquired lower respiratory tract superinfections (p = 0.0054), and use of inotropic support (p = 0.0078). The importance of prevention of hospital-acquired superinfections and permanent optimization of our antimicrobial strategies warranting efficacy of the initial antimicrobial therapy is underlined.

Adult↗
PubMed1996

Severe community-acquired pneumonia in ICUs: prospective validation of a prognostic score.

OBJECTIVE: To determine predictors of intensive care unit (ICU) mortality in patients with community-acquired pneumonia (CAP), to develop a pneumonia-specific prognostic index, and to evaluate this index prospectively. DESIGN: Combined retrospective and prospective clinical study over two periods: January 1987-December 1992 and January 1993-December 1994. SETTING: Four medical ICUs in the north of France. PATIENTS: Derivation cohort: 335 patients admitted to one ICU were retrospectively studied to determine prognosis factors and to develop a pneumonia-specific prognostic index. Validation cohort: 125 consecutive patients, admitted to four ICUs, were prospectively enrolled to evaluate this index. RESULTS: In the derivation cohort, 16 predictors of mortality were identified and assigned a value directly proportional to their magnitude in the mortality model: aspiration pneumonia (-0.37), grading of sepsis > or = 11 (-0.2), antimicrobial combination (-0.01), Glasgow score > 12+mechanical ventilation (MV) (+0.09), serum creatinine > or = 15 mg/l (+0.22), chest involvement shown by X-ray > or = 3 lobes (+0.28), shock (+0.29), bacteremia (+0.29), initial MV (+0.29), underlying ultimately or rapidly fatal illness (+0.31), Simplified Acute Physiology Score > or = 12 (+0.49), neutrophil count < or = 3500/ mm3 (+0.52), acute organ system failure score > or = 2 (+0.64), delayed MV (+0.67), immunosuppression (+1.38), and ineffective initial antimicrobial therapy (+1.5). An index was obtained by adding each patient's points. According to a receiver operating characteristic curve, the cut-off value of this index was 2.5. In the validation cohort, an index of > or = 2.5 could predict death with a positive predictive value of 0.92, sensitivity 0.61, and specificity 0.98. CONCLUSION: This index, which performs well in classifying patients at high-risk of death, may help physicians in initial patient care (appropriateness of the initial antimicrobial therapy) and guide future clinical research (analysis and design of therapeutic trials).

Adolescent↗
PubMed1996

Reliability of quantitative cultures of protected specimen brush after freezing.

Protected specimen brush (PSB) is considered to be one of the standard methods for diagnosing mechanical ventilator-acquired pneumonia at a threshold value > or = 10(3) cfu/ml. Nevertheless, this procedure requires immediate cultures which are not always possible 24 h per day. We therefore wanted to appreciate the diagnostic value of delayed quantitative cultures after specimen freezing. PSB was performed by fiberoptic bronchoscopy on 43 mechanically ventilated patients with suspicion of nosocomial bronchopneumonia. After PSB procedure, two aliquots of 0.5 ml were prepared. One aliquot was plated immediately on different culture media (Group 1). A second aliquot was frozen at -80 degrees C for 24 h, then plated on the same culture media as Group 1 (Group 2). All samples were incubated for 48 h. The diagnostic value threshold of PSB was 10(3) cfu/ml. A total of 47 samples were performed on 43 patients. In Group 1, cultures from PSB were positive in 26 samples and revealed 41 species yielding > or = 10(3) cfu/ml. In Group 2, PSB cultures were positive in 24 samples and revealed 36 species yielding > or = 10(3) cfu/ml. Despite a mean decrease in bacterial count of 1.00 +/- 1.44 log 10 (p < 0.001), most important for Streptococcus pneumoniae and Escherichia coli (respectively 3.22 +/- 2.21 log10 and 2.41 +/- 0.52 log 10), sensitivity and specificity of quantitative cultures after specimen freezing, compared with immediate cultures, were 88% and 100% respectively. We concluded that specimens from PSB could be frozen at -80 degrees C with good reliability except for S. pneumoniae and E. coli, enabling PSB procedure to be performed around the clock.

Bronchi↗
PubMed1995

A five-year study of severe community-acquired pneumonia with emphasis on prognosis in patients admitted to an intensive care unit.

OBJECTIVES: To characterize the epidemiology and to determine the prognosis factors in severe community-acquired pneumonia among patients admitted to an intensive care unit. DESIGN: Retrospective clinical study. SETTING: Intensive Care and Infectious Diseases Unit of a municipal general hospital of Lille University Medical School. PATIENTS: 299 consecutive patients exhibiting severe community-acquired pneumonia. MEASUREMENTS AND RESULTS: On admission to ICU, 149 patients required mechanical ventilation for acute respiratory failure and 44 exhibited septic shock. Pulmonary involvement was bilateral in 71 patients. There were 260 organisms isolated from 197 patients (65.9%), the most frequent being Streptococcus pneumoniae (n = 80), Staphylococcus spp. (n = 57) and Gram-negative bacilli (n = 81). Overall mortality was 28.5% (85 patients). According to univariate analysis, mortality was associated with age over 60 years, anticipated death within 5 years, immunosuppression, shock, mechanical ventilation, bilateral pulmonary involvement, bacteremia, neutrophil count < 3500/mm3, total serum protein level < 45 g/l, serum creatinine > 15 mg/l, non-aspiration pneumonia, ineffective initial therapy and complications. Multivariate analysis selected only 5 factors significantly associated with prognosis: anticipated death within 5 years, shock, bacteremia, non-pneumonia-related complications and ineffective initial therapy. CONCLUSION: The effectiveness of the initial therapy appears to be the most significant prognosis factor and, as the one and only related to the initial medical intervention, suggests a need for permanent optimization of our antimicrobial strategies.

Adolescent↗
PubMed1995

Should Pseudomonas aeruginosa isolates resistant to one of the fluorinated quinolones be tested for the others? Studies with an experimental model of pneumonia.

A clinical isolate of Pseudomonas aeruginosa resistant to pefloxacin (Pef) but susceptible to ciprofloxacin (Cip) was studied to compare the in vitro and in vivo activities of Pef, ofloxacin (Ofl), and Cip. The time-kill curve method showed no bactericidal activity for Pef and Ofl, but a reduction of 4 log10 CFU/ml was achieved with Cip at 1 h. A model of experimental P. aeruginosa pneumonia was used to evaluate in vivo the relevance of the difference in susceptibility observed in vitro. At 36 h, a 100% cumulative survival rate was observed in Cip-treated rats, which was far higher than the survival rate obtained with Pef (53%) or Ofl (46%) (P < 0.001). At 4 h, no bacteremia was observed in Cip-treated rats, whereas 93% of the Pef-treated rats and 80% of the Ofl-treated rats were bacteremic (P < 0.001). The best pulmonary bacterial clearance was observed with Cip. Interestingly, Pef and Ofl, to which the strain was resistant in vitro, showed a fairly good in vivo activity despite sub-MIC concentrations. Cip was more effective than Pef and Ofl in terms of pulmonary and systemic bactericidal activity and provided the best survival rate in animals. We conclude that differences between the different quinolones in terms of the organism's sensitivity assessed in vitro may be relevant and that it might be useful to reconsider the use of a quinolone to which P. aeruginosa shows resistance if the organism shows sensitivity to no other agent.

Animals↗
PubMed1995

ATP-sensitive K+ channel blockade impairs O2 extraction during progressive ischemia in pig hindlimb.

Tissues maintain O2 consumption (VO2) when blood flow and O2 delivery (DO2) are decreased by better matching of blood flow to meet local cellular O2 demand, a process that increases extraction of available O2. This study tested the hypothesis that ATP-sensitive K+ channels play a significant role in the response of pig hindlimb to ischemia. We pump perfused the vascularly isolated but innervated right hindlimb of 14 anesthetized pigs with normoxic blood while measuring hindlimb DO2, VO2, perfusion pressure, and cytochrome aa3 redox state. In one-half of the pigs, the pump-perfused hindlimb was also infused with 10 micrograms.min-1.kg-1 of glibenclamide, a potent blocker of ATP-sensitive K+ channels. Control animals were infused with 5% glucose solution alone. Blood flow was then progressively reduced in both groups in 10 steps at 10-min intervals. Glibenclamide had no effect on any preischemic hindlimb or systemic measurements. Hindlimb VO2 and cytochrome aa3 redox state began to decrease at a significantly higher DO2 in glibenclamide-treated compared with control pigs. At this critical DO2, the O2 extraction ratio (VO2/DO2) was 53 +/- 4% in the glibenclamide group and 73 +/- 5% in the control group (P < 0.05). Hindlimb vascular resistance increased significantly with ischemia in the glibenclamide group but did not change in the control group. We conclude that ATP-sensitive K+ channels may be importantly involved in the vascular recruitment response that tried to meet tissue O2 needs as blood flow was progressively reduced in the pig hindlimb.

Adenosine Triphosphate↗
PubMed1993

Pharmacokinetics of vancomycin during continuous hemodiafiltration.

OBJECTIVE: To study the pharmacokinetics of vancomycin in three patients with acute renal failure related to multi-organ failure during continuous venovenous hemodiafiltration (CVVHD). DESIGN: Prospective exploratory, open-labelled study. SETTING: Critical Care Unit in a University Medical Centre. PATIENTS: 3 patients exhibiting hemodynamic instability and oligo-anuric acute renal failure requiring extra-renal epuration were included in this study. INTERVENTION: Every patient received 7.5 mg/kg IV vancomycin over 1 h for a documented or suspected nosocomial staphylococcal infection. Serum and dialysate outlets samples were collected before infusion and 1, 3, 6, 12, 18, 24 after the end of infusion. MEASUREMENTS AND RESULTS: Mean age was 58.7 years (range 41-79) and mean SAPS 15.7 (9-23). The mean peak concentrations were 27.3 mg/l (range 15.6-45.6) one hour after the end of infusion. The average remaining vancomycin concentration 24 h after the onset of infusion was 3.6 mg/l (range 2.6-4.5). The mean terminal disposition rate constant and elimination half-life were 0.05 h-1 and 13.9 h respectively. Mean total body clearance was 38.9 +/- 4.3 ml/min and dialysate outlet (DO) clearance 4.2 +/- 1.3 ml/min. The mean volume of distribution was 47.4 +/- 6.4 l. CONCLUSION: CVVHD is effective for vancomycin elimination. In these patients, the elimination half-life is almost constant, involving a following injection of vancomycin 12 h later to achieve effective concentrations.

Acute Kidney Injury↗
PubMedDate not supplied

Exchange transfusion for severe malaria.

BACKGROUND: Exchange transfusion (ET) is a controversial ancillary treatment of severe falciparum malaria. PATIENTS AND METHODS: We conducted a retrospective analysis of severe malaria treated in our institution. Nine cases of ET were identified between 1991 and 1998 and compared to 12 controls with similar parasitemia. RESULTS: Groups were similar at admission except for an increased age in the ET group (p < 0.02). All patients received iv quinine. Outcome was similar in both groups (two deaths in the ET group, three in the control group). However, in patients with parasitemia > 30%, the death rate was significantly lower in ET patients than in controls (0/4 vs 3/3, p < 0.029). CONCLUSION: Despite definitive data from controlled trials, we suggest that ET should be considered in severe malaria cases with very high parasitemia and severity criteria or worsening clinical condition despite adequate chemotherapy.

Adult↗