François Stéphan

High-Flow Nasal Oxygen vs Noninvasive Positive Airway Pressure in Hypoxemic Patients After Cardiothoracic Surgery: A Randomized Clinical Trial

IMPORTANCE Noninvasive ventilation delivered as bilevel positive airway pressure (BiPAP) is often used to avoid reintubation and improve outcomes of patients with hypoxemia after cardiothoracic surgery. High-flow nasal oxygen therapy is increasingly used to improve oxygenation because of its ease of implementation, tolerance, and clinical effectiveness. OBJECTIVE To determine whether high-flow nasal oxygen therapy was not inferior to BiPAP for preventing or resolving acute respiratory failure after cardiothoracic surgery. DESIGN AND SETTING Multicenter, randomized, noninferiority trial (BiPOP Study) conducted between June 15, 2011, and January 15, 2014, at 6 French intensive care units. PARTICIPANTS A total of 830 patients who had undergone cardiothoracic surgery, of which coronary artery bypass, valvular repair, and pulmonary thromboendarterectomy were the most common, were included when they developed acute respiratory failure (failure of a spontaneous breathing trial or successful breathing trial but failed extubation) or were deemed at risk for respiratory failure after extubation due to preexisting risk factors. INTERVENTIONS Patients were randomly assigned to receive high-flow nasal oxygen therapy delivered continuously through a nasal cannula (flow, 50 L/min; fraction of inspired oxygen [FiO2], 50%) (n = 414) or BiPAP delivered with a full-face mask for at least 4 hours per day (pressure support level, 8 cm H2O; positive end-expiratory pressure, 4 cm H2O; FiO2, 50%) (n = 416). MAIN OUTCOMES AND MEASURES The primary outcome was treatment failure, defined as reintubation, switch to the other study treatment, or premature treatment discontinuation (patient request or adverse effects, including gastric distention). Noninferiority of high-flow nasal oxygen therapy would be demonstrated if the lower boundary of the 95% CI were less than 9%. Secondary outcomes included mortality during intensive care unit stay, changes in respiratory variables, and respiratory complications. RESULTS High-flow nasal oxygen therapy was not inferior to BiPAP: the treatment failed in 87 of 414 patients with high-flow nasal oxygen therapy (21.0%) and 91 of 416 patients with BiPAP (21.9%) (absolute difference, 0.9%; 95% CI, -4.9% to 6.6%; P = .003). No significant differences were found for intensive care unit mortality (23 patients with BiPAP [5.5%] and 28 with high-flow nasal oxygen therapy [6.8%]; P = .66) (absolute difference, 1.2% [95% CI, -2.3% to 4.8%]. Skin breakdown was significantly more common with BiPAP after 24 hours (10% vs 3%; 95% CI, 7.3%-13.4% vs 1.8%-5.6%; P < .001). CONCLUSIONS AND RELEVANCE Among cardiothoracic surgery patients with or at risk for respiratory failure, the use of high-flow nasal oxygen therapy compared with intermittent BiPAP did not result in a worse rate of treatment failure. The findings support the use of high-flow nasal oxygen therapy in similar patients. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01458444.

Reduction of Urinary Tract Infection and Antibiotic Use after Surgery: A Controlled, Prospective, Before-After Intervention Study

BACKGROUND Urinary tract infection is the most frequent health care-associated complication. We hypothesized that the implementation of a multifaceted prevention strategy could decrease its incidence after surgery. METHODS In a controlled, prospective, before-after intervention trial with 1328 adult patients scheduled for orthopedic or abdominal surgery, nosocomial infection surveillance was conducted until hospital discharge. A multifaceted intervention including specifically tailored, locally developed guidelines for the prevention of urinary tract infection was implemented for orthopedic surgery patients, and abdominal surgery patients served as control subjects. Infectious and noninfectious complications, adherence to guidelines, and antibiotic use were monitored before and after the intervention and again 2 years later. RESULTS The incidence of urinary tract infection decreased from 10.4 to 3.9 episodes per 100 patients in the intervention group (incidence-density ratio, 0.41; 95% CI, 0.20-0.79; P=.004). Adherence to guidelines was 82.2%. Both the frequency and the duration of urinary catheterization decreased following the intervention. Recourse to antibiotic therapy after surgery dropped in the intervention group from 17.9 to 15.6 defined daily doses per 100 patient-days (P<.005) because of a reduced need for the treatment of urinary tract infection (P<.001). Follow-up after 2 years revealed a sustained impact of the strategy and a subsequent low use of antibiotics, consistent with stable adherence to guidelines (80.8%). CONCLUSIONS A multifaceted prevention strategy can dramatically decrease postoperative urinary tract infection and contribute to the reduction of the overall use of antibiotics after surgery.

Mortality Attributable to Nosocomial Infections in the ICU

Although a direct relationship between nosocomial infection and mortality in intensive care unit (ICU) patients has not always been demonstrated formally, it is possible to conclude that nosocomial infections increase the risk of death in critically ill patients. A more precise analysis indicates that: 1) this effect is highly probable for pneumonia, doubtful for bacteremia, and uncertain for urinary tract infection; 2) risk increases with duration of stay in the ICU; 3) bacterial etiology modifies the risk; and 4) this effect is stronger in less severely ill patients, probably because the severity of underlying disease remains the most significant factor.

Impairment of polymorphonuclear neutrophil functions precedes nosocomial infections in critically ill patients

Objective A postinjury immunodepression involving neutrophil functions has been described in critically ill patients. The aim of this prospective study was to search for a relationship between an impairment of neutrophil functions and the subsequent development of nosocomial infection. Design Twenty-one severely ill (simplified acute physiology score II >20 on admission), nonimmunosuppressed patients who were receiving no antibiotics active against methicillin-resistant Staphylococcus aureus and highly resistant Pseudomonas aeruginosa were included. Twelve healthy subjects constituted a control group. Measurements Neutrophil functions (phagocytosis and bactericidal activity toward S. aureus and P. aeruginosa in homologous plasma, reactive oxygen species secretion) were studied at day 4 ± 1 after admission, and occurrence of nosocomial infection was prospectively recorded over the following 5 days. Interleukin-10 concentration was assessed by enzyme-linked immunosorbent assay. Results are expressed as median (25th–75th percentiles). Main Results Six out of the 21 patients acquired a nosocomial infection during the 5 days after blood sampling (infected group). Compared with the patients who did not acquire nosocomial infection (noninfected group, n = 15), the neutrophils of the infected group demonstrated a higher percentage of intracellular bacterial survival (17% [2% to 67%] vs. infected: 62% [22% to 100%], p < .05), leading to an impairment of S. aureus killing in homologous plasma (killed bacteria: 4.93 log10 colony forming units/mL [4.24–5.29] vs. infected: 3.62 log10 colony forming units/mL [0.00–4.58], p < .05). Interleukin-10 plasma concentration was higher in infected patients (78 pg/mL [60–83]) compared with noninfected patients (22 pg/mL [14–58], p < .05). By contrast, P. aeruginosa killing was similar in patients whether or not they acquired a nosocomial infection. Conclusion A decrease in S. aureus killing capabilities of neutrophils can be evidenced within the days before occurrence of a nosocomial infection.

Molecular Diversity and Routes of Colonization of Candida albicans in a Surgical Intensive Care Unit, as Studied Using Microsatellite Markers

To evaluate the colonization of Candida species and the importance of cross-contamination with Candida albicans, we prospectively screened clinical specimens obtained from surgical patients in the intensive care unit (ICU) who had a high risk of yeast colonization. Genotyping of C. albicans was performed using microsatellite markers. Thirty-six of 94 patients acquired nosocomial yeast colonization and/or infection. A total of 1126 specimens were cultured, 167 (15%) of which yielded yeasts. All 122 isolates of C. albicans recovered from the 30 C. albicans-positive patients were genotyped. Twenty-four different genotypes were identified. No genotype was systematically associated with a specific room or time. Isolates recovered from different body sites of patients at different times had identical genotypes. Acquisition of C. albicans in the surgical ICU seems to be mainly endogenous. Microsatellite markers should also be developed for typing non-albicans Candida species to learn whether their epidemiology differs from that of C. albicans.

Hand-cleansing during postanesthesia care.

Background Transmission of microorganisms from the hands of healthcare workers is the main source of cross-infection and can be prevented by hand-cleansing. The authors assessed the compliance rate with hand-cleansing practices in the postanesthesia care unit and investigated factors associated with noncompliance. Methods Patient care activities, indications for and compliance of postanesthesia care unit staff with hand-cleansing, defined as either washing hands with soap and water or rubbing hands with alcohol, were monitored at the time of patient admission and during their stay. Multivariate analysis identified predictors of noncompliance with hand-cleansing on admission after adjustment for confounders. Results A total of 3,143 patient care activities, including 1,091 opportunities for hand-cleansing at high or medium risk for cross-transmission, were recorded among 187 patients. The higher the workload, the higher the number of indications for hand-cleansing and the lower the compliance. Average compliance with hand-cleansing at postanesthesia care unit admission was 19.6%. Independent predictors for noncompliance included caring for patients older than 65 yr (odds ratio, 2.23; 95% confidence interval, 1.40–3.57) and those recovering from clean/clean–contaminated surgery (odds ratio, 2.27; 95% confidence interval, 1.11–4.76), as well as high intensity of patient care (odds ratio, 1.01 per patient care activity; 95% confidence interval, 1.0–1.02). Compliance with hand-cleansing for patients already admitted to the postanesthesia care unit was 12.5%. Conclusions Failure to cleanse hands during patient care is common in the postanesthesia care unit and is associated with identifiable factors. The close relation between the intensity of patient care and noncompliance argues that hand-cleansing should not be viewed as a problematic individual behavior only, and system change must be considered in prevention strategies.

Evaluation by polymerase chain reaction of cytomegalovirus reactivation in intensive care patients under mechanical ventilation

ObjectiveThe study was undertaken to determine if critically ill patients under mechanical ventilation could reactivate latent cytomegalovirus (CMV) in either lung or blood.DesignProspective study in critically ill patients.SettingThe study was performed in a multidisciplinary intensive care unit in a university hospital.Patients23 non-immunocompromised, mechanically ventilated patients who were anti-CMV immunoglobulin G-positive. Ten immunocompromised patients with active CMV infection and 16 asymptomatic CMV seropositive non-immunocompromised patients constituted the positive and negative control groups.Measurements and resultsThe presence of CMV in blood and bronchoalveolar lavage (BAL) was evaluated by both viral cultures and polymerase chain reaction (PCR). Thirty-seven blood and 22 BAL samples were investigated. Sequential samples were evaluated in 8 patients. For PCR, a 290 bp fragment in the first exon of the immediate early 1 gene was amplified. In order to exclude inhibitors of PCR amplification, a 268 bp fragment of the β-globin gene was concurrently amplified in all samples. Viral cultures of blood and BAL were negative in all 23 non-immunocompromised, mechanically ventilated patients. Moreover, no CMV DNA could be amplified in blood or BAL samples, whereas a β-globin amplification was observed in all samples.ConclusionIn a series of 23 critically ill patients under mechanical ventilation who were seropositive for CMV, no reactivation of CMV in blood or lung was demonstrated.

Uniform distribution of three Candida albicans microsatellite markers in two French ICU populations supports a lack of nosocomial cross-contamination

BackgroundThe nosocomial acquisition of Candida albicans is a growing concern in intensive care units (ICUs) and understanding the route of contamination is relevant for infection control guidelines.MethodsTo analyze whether there is a specific ecology for any given hospital, we genotyped C. albicans isolates of the ICU of Versailles hospital (Hospital A) and compared the results with those previously obtained in another ICU in Henri Mondor hospital (Hospital B) using three polymorphic microsatellite markers (PMM).ResultsAmong 36 patients with at least one positive culture for C. albicans, 26 had a specific multilocus genotype, two shared a common multilocus genotype, and 8 had the most common multilocus genotype found in the general population. The time interval between periods of hospitalization between patients with common genotypes differed by 13 to 78 days, thus supporting a lack of direct contamination. To confirm this hypothesis, the multilocus genotypic distributions of the three PMM were compared between the two hospitals. No statistically significant difference was observed. Multiple correspondences analysis did not indicate the association of a multilocus genotypic distribution with any given hospital.ConclusionThe present epidemiological study supports the conclusions that each patient harbours his/her own isolate, and that nosocomial transmission is not common in any given ICU. This study also supports the usefulness and practicability of PMM for studying the epidemiology of C. albicans.

Nosocomial Infections and Outcome of Critically Ill Elderly Patients after Surgery

Background The relation between older age and nosocomial infection and mortality in the intensive care unit (ICU) is still a controversial issue. Methods The authors prospectively studied 406 patients admitted to a surgical ICU, 106 of whom were more than 75 yr old. Information concerning ICU-acquired nosocomial infections, severity of illness, therapeutic activity, and hospital outcome was collected. A Cox proportional hazard analysis was used to evaluate potential risk factors for ICU-acquired nosocomial infections, ICU, and hospital death. Results During their ICU stay, 23 elderly patients experienced 40 nosocomial infections, 28 “young” patients (< 60 yr) experienced 54 nosocomial infections, and 52 “intermediate age” patients (60–75 yr) experienced 98 nosocomial infections. Incidence density of nosocomial infections was 4.9% patient days for elderly patients, 4.7% for young patients, and 6.0% for intermediate age patients (no significance). The frequency distribution of the various microorganisms isolated was similar between the three groups. Compared with younger patients, elderly patients had a higher Acute Physiology and Chronic Health Evaluation II score and a higher ICU and hospital mortality rate. Despite a higher level of severity of illness, elderly patients had a reduction of therapeutic activity. However, Cox proportional hazard analysis showed that age more than 75 yr was not a risk factor for ICU-acquired nosocomial infection, ICU, or hospital death. Conclusions In patients referred to a surgical ICU after a surgical procedure, age more than 75 yr by itself does not appear to be a significant predictor of ICU-acquired nosocomial infection or mortality rate during the ICU stay. However, it appears that patients more than 60 yr have a higher incidence of nosocomial infection in ICU.

Lung and heart-lung transplantation for systemic sclerosis patients. A monocentric experience of 13 patients, review of the literature and position paper of a multidisciplinary Working Group

Systemic sclerosis per se should not be considered as an a priori contraindication for a pre-transplantation assessment in patients with advanced interstitial lung disease and/or pulmonary hypertension. For lung or heart-lung transplantation, a multidisciplinary approach, adapting the pre-transplant assessment to systemic sclerosis and optimizing systemic sclerosis patient management before, during and after surgery should improved the short- and long-term prognosis. Indications and contraindications for transplantation have to be adapted to the specificities of systemic sclerosis. A special focus on the digestive tract involvement and its thorough evaluation are mandatory before transplantation in systemic sclerosis. As the esophagus is almost always involved, isolated gastro-oesophageal reflux disease, pH metry and/or manometry abnormalities should not be a systematic per se contraindication for pre-transplantation assessment. Corticosteroids may be harmful in systemic sclerosis as they are associated with acute renal crisis. A low dose corticosteroids protocol for immunosuppression is therefore advisable in systemic sclerosis.