Hervé Dupont

Upper digestive intolerance during enteral nutrition in critically ill patients: frequency, risk factors, and complications.

ObjectiveTo study the frequency of and risk factors for increased gastric aspirate volume (GAV) and upper digestive intolerance and their complications during enteral nutrition (EN) in critically ill patients. DesignProspective observational study. SettingIntensive care unit (ICU) in a general hospital. PatientsA total of 153 patients with nasogastric tube feeding. InterventionsNone. Measurements and Main Results Upper digestive intolerance was considered when GAV was between 150 and 500 mL at two consecutive measurements, when it was >500 mL, or when vomiting occurred. Forty-nine patients (32%; 95% confidence interval [CI], 25%–42%) presented increased GAV after a median EN duration of 2 days (range, 1–16 days), and 70 patients (46%; 95% CI, 38%–54%) presented upper digestive intolerance. Independent risk factors for high GAV were GAV >20 mL before the start of EN (odds ratio [OR], 2.16; 95% CI, 1.11–4.18;p = .02), GAV >100 mL during EN (OR, 1.49; 95% CI, 1.01–2.19;p < .05), sedation during EN (OR, 1.78; 95% CI, 1.17–2.71;p = .007), use of catecholamines during EN (OR, 1.81; 95% CI, 1.21–2.70;p = .004). Complications related to high GAV were a lower feed intake (15 ± 7 vs. 19 ± 8 kcal/kg/day;p = .0004) and vomiting (53% vs. 23%;p = .0002). Complications related to upper digestive intolerance were the development of pneumonia (43% vs. 24%;p = .01), a longer ICU stay (23 ± 21 vs. 15 ± 16 days;p = .007), and a higher ICU mortality (41% vs. 25%;p = .03), even after adjustment for Simplified Acute Physiology Score II (OR, 1.48; 95% CI, 1.04–2.10;p = .028). ConclusionIn ICU patients receiving nasogastric tube feeding, high gastric aspirate volume was frequent, occurred early, and was more frequent in patients with sedation or catecholamines. High gastric aspirate volume was an early marker of upper digestive intolerance, which was associated with a higher incidence of nosocomial pneumonia, a longer ICU stay, and a higher ICU mortality.

Candida as a risk factor for mortality in peritonitis.

Objective:The clinical significance of Candida cultured from peritoneal fluid specimens remains a matter of debate. None of the studies that have addressed this issue have clearly distinguished between community-acquired peritonitis and nosocomial peritonitis. The current study tried to differentiate the pathogenic role of Candida in these two clinical settings and assess its importance on outcome. Design:A multiple-center, retrospective, case-control study was conducted in intensive care unit patients. The interaction between mortality rates and type of patients was assessed. In the case of a significant interaction, a separate analysis of mortality and morbidity was planned. Setting:Seventeen intensive care units in teaching and nonteaching hospitals. Patients:Cases were patients operated on for peritonitis with Candida cultured from the peritoneal fluid, whereas controls were operated patients free from yeast. Cases and controls were matched for type of infection, Simplified Acute Physiology Score II, age, and time period of hospitalization. Interventions:None. Measurements and Main Results:The following characteristics were collected: demographic variables, underlying disease, severity score, site of infection, microbiological features, and anti-infective treatments. Survival was defined as the main outcome criterion and morbidity variables as secondary criteria. Odds ratios of mortality were calculated. Matching was achieved in 91 cases and 168 controls. Matching criteria, clinical characteristics, and mortality rate were not statistically different between cases and controls. A significant interaction was demonstrated between mortality rates and type of infection, leading to separate analysis of patients with community-acquired peritonitis and nosocomial peritonitis. The subgroup analysis demonstrated an increased mortality rate only in nosocomial peritonitis with fungal isolates (48% vs. 28% in controls, p < .01). Upper gastrointestinal tract site (odds ratio, 4.9; 95% confidence interval, 1.6–14.8) and isolation of Candida species (odds ratio, 3.0; 95% confidence interval, 1.3–6.7, p < .001) were found to be independent risk factors of mortality in nosocomial peritonitis patients. Conclusions:Isolation of Candida species appears to be an independent risk factor of mortality in nosocomial peritonitis but not in community-acquired peritonitis.

Can yeast isolation in peritoneal fluid be predicted in intensive care unit patients with peritonitis

ObjectiveTo generate and validate a predictive score of yeast isolation based on independent risk factors of yeast isolation in intensive care unit patients with peritonitis. DesignRetrospective cohort study to determine independent risk factors of yeast isolation, generation of the score, and validation in a prospective cohort of patients with peritonitis. SettingTertiary-care, university-affiliated hospital. PatientsTwo hundred twenty-one patients with peritonitis hospitalized in a surgical intensive care unit between 1994 and 1999 for the retrospective cohort and 57 patients in the prospective cohort (2000). Measurements and Main ResultsFour independent risk factors of yeast isolation in peritoneal fluid (similar odds ratio) were found in the retrospective cohort: female gender, upper gastrointestinal tract origin of peritonitis, intraoperative cardiovascular failure, and previous antimicrobial therapy at least 48 hrs before the onset of peritonitis. A score based on the number of risk factors was constructed (grade A = zero or one risk factor, grade B = at least two risk factors, grade C = at least three risk factors, and grade D = four risk factors), and validated in the prospective cohort. For a grade C score, sensitivity was 84%, specificity was 50%, positive and negative predictive values were 67% and 72%, respectively, and overall accuracy was 71%. ConclusionsFour independent risk factors of yeast isolation in the peritoneal fluid were identified in critically ill surgical patients with peritonitis. The presence of at least three of these factors (grade C score) was associated with a high rate of yeast detection. This approach could be helpful to initiate early antifungal therapy in this patient population.

Leptospirosis: Prognostic Factors Associated with Mortality

To determine the prognostic factors for leptospirosis, we conducted a retrospective study of data collected in the emergency department of our hospital between 1989 and 1993. Sixty-eight patients, for whom the diagnosis of leptospirosis was based on pertinent clinical and epidemiological data and positive serology, were included in this study. Fifty-six patients (82%) were discharged from the hospital, and 12 (18%) died. Multivariate logistic regression demonstrated that five factors were independently associated with mortality: dyspnea (odds ratio [OR], 11.7; 95% confidence interval [CI], 2.8-48.5; P < .05), oliguria (OR, 9; CI, 2.1-37.9; P < .05); white blood cell count, >12,900/mm3 (OR, 2.5; CI, 1.8-3.5; P < or = .01), repolarization abnormalities on electrocardiograms (OR, 5.9; CI, 1.4-24.8; P < or = .01), and alveolar infiltrates on chest radiographs (OR, 7.3; CI, 1.7-31.7; P < or = .01). Identification of these factors on admission might provide useful selection criteria for patients who need early transfer to the intensive care unit.

Guidelines for management of intra-abdominal infections.

Intra-abdominal infections are one of the most common gastrointestinal emergencies and a leading cause of septic shock. A consensus conference on the management of community-acquired peritonitis was published in 2000. A new consensus as well as new guidelines for less common situations such as peritonitis in paediatrics and healthcare-associated infections had become necessary. The objectives of these Clinical Practice Guidelines (CPGs) were therefore to define the medical and surgical management of community-acquired intra-abdominal infections, define the specificities of intra-abdominal infections in children and describe the management of healthcare-associated infections. The literature review was divided into six main themes: diagnostic approach, infection source control, microbiological data, paediatric specificities, medical treatment of peritonitis, and management of complications. The GRADE(®) methodology was applied to determine the level of evidence and the strength of recommendations. After summarising the work of the experts and application of the GRADE(®) method, 62 recommendations were formally defined by the organisation committee. Recommendations were then submitted to and amended by a review committee. After 2 rounds of Delphi scoring and various amendments, a strong agreement was obtained for 44 (100%) recommendations. The CPGs for peritonitis are therefore based on a consensus between the various disciplines involved in the management of these patients concerning a number of themes such as: diagnostic strategy and the place of imaging; time to management; the place of microbiological specimens; targets of empirical anti-infective therapy; duration of anti-infective therapy. The CPGs also specified the value and the place of certain practices such as: the place of laparoscopy; the indications for image-guided percutaneous drainage; indications for the treatment of enterococci and fungi. The CPGs also confirmed the futility of certain practices such as: the use of diagnostic biomarkers; systematic relaparotomies; prolonged anti-infective therapy, especially in children.

Assessing fluid responsiveness in critically ill patients: False-positive pulse pressure variation is detected by Doppler echocardiographic evaluation of the right ventricle

Objectives:To determine whether peak systolic velocity of tricuspid annular motion assessed by tissue Doppler echocardiography (Sta), a right ventricular function parameter, can discriminate patients with true- and false-positive pulse pressure variation. Pulse pressure variation is used to predict fluid responsiveness in mechanically ventilated patients. However, this parameter has been reported to be falsely positive, especially in patients with right ventricular dysfunction. Design:A prospective study. Setting:Medical and surgical intensive care unit of a university hospital. Patients:Thirty- five mechanically ventilated patients hospitalized for >24 hrs with a pulse pressure variation of >12%. Interventions:Doppler echocardiography (including measurement of Sta and stroke volume) was performed before and after infusion of 500 mL of colloid solution. Patients were classified into two groups according to their response to fluid infusion: responders (at least 15% increase in stroke volume) and nonresponders. Measurements and Main Results:Twenty-three patients (66%) were responders (true-positive group) and 12 (34%) were nonresponders (false-positive group). Before volume expansion, Sta was statistically lower in the nonresponder group (0.13 [0.04] vs. 0.20 [0.05], p = .0004). The area under the curve of the receiver operating characteristic curve was 0.87 (95% confidence interval, 0.74-1). In patients with pulse pressure variation of >12%, a Sta cutoff value of 0.15 m/s discriminated between responders and nonresponders with a sensitivity of 91% (80-100) and a specificity of 83% (62-100). Conclusions:A Sta value of <0.15 m/s seems to be an accurate parameter to detect false-positive pulse pressure variation. Echocardiography should therefore be performed before fluid infusion in patients with pulse pressure variation of >12%.

The passive leg-raising maneuver cannot accurately predict fluid responsiveness in patients with intra-abdominal hypertension.

Objectives:The passive leg-raising maneuver is a reversible fluid-loading procedure used to predict fluid responsiveness in mechanically ventilated patients. The aim of the present study was to determine whether intra-abdominal hypertension (which impairs venous return) reduces the ability of passive leg raising to detect fluid responsiveness in critically ill ventilated patients. Design:A prospective study. Setting:The medical and surgical intensive care unit of a university medical center. Patients:Forty-one mechanically ventilated patients with a pulse pressure variation of >12%. Interventions:Stroke volume was continuously monitored by esophageal Doppler. Intra-abdominal pressure was measured via bladder pressure. After a passive leg-raising maneuver and a return to baseline, fluid loading with 500 mL of saline was performed. Hemodynamic parameters were recorded at each step. Nonresponders to volume loading were not analyzed (10 patients). Thirty-one patients were classified into two groups according to their response to passive leg raising: responders to passive leg raising (at least a 12% increase in stroke volume) and nonresponders to passive leg raising. Measurements and Main Results:Sixteen patients (52%) were responders to passive leg raising, and 15 (48%) were nonresponders to passive leg raising (i.e., false negatives). At baseline, the median intra-abdominal pressure was significantly higher in the nonresponders to passive leg raising than in the responders to passive leg raising (20 [6.5] vs. 11.5 [5.5], respectively; p < .0001). The area under the receiver-operating characteristic curve was 0.969 ± 0.033. An intra-abdominal pressure cutoff value of 16 mm Hg discriminated between responders to passive leg raising and nonresponders to passive leg raising with a sensitivity of 100% (confidence interval, 78–100) and a specificity of 87.5% (confidence interval, 61.6–98.1). An intra-abdominal pressure of ≥16 mm Hg was the only independent predictor of nonresponse to passive leg raising in a multivariate analysis (odds ratio, 2.6 [confidence interval, 1.1–6.6]; p = .04). Conclusions:An intra-abdominal pressure of ≥16 mm Hg seems to be responsible for false negatives to passive leg raising. Hence, the intra-abdominal pressure should be measured in critically ill ventilated patients, especially before performing passive leg raising.

Clinical and microbiological profiles of community-acquired and nosocomial intra-abdominal infections: results of the French prospective, observational EBIIA study

OBJECTIVES The EBIIA (Etude épidémiologique Bactério-clinique des Infections Intra-Abdominales) study was designed to describe the clinical, microbiological and resistance profiles of community-acquired and nosocomial intra-abdominal infections (IAIs). PATIENTS AND METHODS From January to July 2005, patients undergoing surgery/interventional drainage for IAIs with a positive microbiological culture were included by 25 French centres. The primary endpoint was the epidemiology of the microorganisms and their resistance to antibiotics. Multivariate analysis was carried out using stepwise logistic regression to assess the factors predictive of death during hospitalization. RESULTS Three hundred and thirty-one patients (234 community-acquired and 97 nosocomial) were included. The distribution of the microorganisms differed according to the type of infection. Carbapenems and amikacin were the most active agents in vitro against Enterobacteriaceae in both community-acquired and nosocomial infections. Against Pseudomonas aeruginosa, amikacin, imipenem, ceftazidime and ciprofloxacin were the most active agents in community-acquired infections, while imipenem, cefepime and amikacin were the most active in nosocomial cases. Against the Gram-positive bacteria, vancomycin and teicoplanin were the most active in both infections. Against anaerobic bacteria, the most active agents were metronidazole and carbapenems in both groups. Empirical antibiotic therapy adequately targeted the pathogens for 63% of community-acquired and 64% of nosocomial peritonitis. The presence of one or more co-morbidities [odds ratio (OR) = 3.17; P = 0.007], one or more severity criteria (OR = 4.90; P < 0.001) and generalized peritonitis (OR = 3.17; P = 0.006) were predictive of death. CONCLUSIONS The principal results of EBIIA are a higher diversity of microorganisms isolated in nosocomial infections and decreased susceptibility among these strains. Despite this, the adequacy of treatment is comparable in the two groups.

Ectoparasitism and vector-borne diseases in 930 homeless people from Marseilles

Abstract: Homeless people are particularly exposed to ectoparasites, but their exposure to arthropod-borne diseases has not been evaluated systematically. A medical team of 27 persons (7 nurses, 6 infectious disease residents or fellows, 2 dermatologists, and 12 infectious disease specialists) visited the 2 shelters in Marseilles, France, for 4 consecutive years. Homeless volunteers were interviewed, examined, and received care; and blood was sampled for cell counts and detection of bacteremia, antibodies to louse-borne (Rickettsia prowazekii, Bartonella quintana, and Borrelia recurrentis), flea-borne (R. typhi, R. felis), mite-borne (R. akari), and tick-borne (R. conorii) bacterial agents. We selected sex- and age-adjusted controls among healthy blood donors. Over 4 years, 930 homeless people were enrolled. Lice were found in 22% and were associated with hypereosinophilia (odds ratio, 5.7; 95% confidence intervals, 1.46-22.15). Twenty-seven patients (3%) with scabies were treated with ivermectin. Bartonella quintana was isolated from blood culture in 50 patients (5.3%), 36 of whom were treated effectively. The number of bacteremic patient increased from 3.4% to 8.4% (p = 0.02) over the 4 years of the study. We detected a higher seroprevalence to Borrelia recurrentis, R. conorii, and R. prowazekii antibodies in the homeless. Our study shows a high prevalence of louse-borne infections in the homeless and a high degree of exposure to tick-borne diseases and scabies. Despite effective treatment for Bartonella quintana bacteremia and the efforts made to delouse this population, Bartonella quintana remains endemic, and we found hallmarks of epidemic typhus and relapsing fever. The uncontrolled louse infestation of this population should alert the community to the possibility of severe re-emerging louse-borne infections.

Postoperative Ketamine Administration Decreases Morphine Consumption in Major Abdominal Surgery : A Prospective, Randomized, Double-Blind, Controlled Study

BACKGROUND:Ketamine decreases postoperative morphine consumption, but its optimal dosing and duration of administration remain unclear. In this study, we compared the effects of ketamine administration on morphine consumption limited to the intraoperative period, or continued for 48 h postoperatively. METHODS:Eighty-one patients scheduled for abdominal surgery were prospectively randomized under double-blind conditions to three groups: (1) PERI group receiving intraoperative and postoperative ketamine for the first 48 h after surgery (2 &mgr;g · kg−1 · min−1 after a 0.5 mg/kg bolus); (2) INTRA group receiving intraoperative ketamine administration only (2 &mgr;g · kg−1 · min−1 after a 0.5 mg/kg bolus); and (3) CTRL group receiving placebo. Morphine consumption, visual analog scale scores and side effects (sedation score, nausea-vomiting score, nightmares, psychiatric disorders, or delusions) were recorded for the first 48 h. RESULTS:Cumulative morphine consumption 24 h after surgery was significantly lower in the PERI group (median = 27 mg, interquartile range = [19]) than in the INTRA group (48 mg [41.5]) and CTRL group (50 mg [21]) (P < 0.005). Postoperative visual analog scale scores were significantly lower in the PERI group and INTRA group than in the CTRL group (P < 0.001). A higher rate of nausea was observed in the CTRL group compared with the PERI group (27% vs 4%, P = 0.005). No difference in sedation scores or psychiatric disorders was observed among groups. CONCLUSIONS:Low-dose ketamine improved postoperative analgesia with a significant decrease of morphine consumption when its administration was continued for 48 h postoperatively, with a lower incidence of nausea and with no side effects of ketamine.