Performance of manual ventilation: how to define its efficiency in bench studies? A review of the literature.

Bench studies have become the preferred way to evaluate the performance of airway equipment, since clinical trials are not specifically required before marketing these devices. However, it is difficult to assess the efficiency of ventilation without recording physiological data. This review analyses how efficiency of manual ventilation has been defined in recent studies, and how their results may be affected. We searched electronic databases from 2000 to April 2014. The main inclusion criterion was the analysis of performance of ventilation. Nine relevant articles were selected from 53 eligible publications. Most studies used the same parameters; tidal volume and ventilation rate. However, there were significant differences between the definitions of performance of ventilation, both in terms of criteria of judgement and methods of analysis. None of these approaches is able to provide a clear understanding of variability of ventilation during a given period. A new definition may increase the relevance of bench studies to clinical medicine, by more appropriately assessing the performance of ventilation.

Reliability of manikin-based studies: an evaluation of manikin characteristics and their impact on measurements of ventilatory variables.

Findings from manikin-based studies on ventilation are commonly directly extrapolated to clinical practice. The aim of this study was to determine how the use of manikins affects measurements of ventilatory variables. We connected a lung simulator to a manikin, which was then ventilated at different inspiratory flows. We defined three experimental models to compare measurements of ventilatory variables between the mechanical ventilator and the lung simulator. Even when no leakage occurred, significant tidal volume deviations were observed; from a mean (SD) of 21 (2) ml to 49 (9) ml, and from 40 (4) ml to 88 (5) ml for invasive and non-invasive ventilation, respectively (p < 0.001). Significant peak pressure deviations from 0.7 (0.1) cmH2 O to 10.6 (0.3) cmH2 O were also recorded during non-invasive ventilation (p < 0.001). Evaluation of manikin resistance and airway dead space may be essential to limit study bias. We suggest a recalibration of the recorded data if comparisons are made between different tests performed at different inspiratory flows.

Successful organ transplantation after treatment of fatal cyanide poisoning with hydroxocobalamin.

BACKGROUND: Cyanide-poisoned patients are potential organ donors provided that organs are not damaged by the poison or by antidotal treatment. CASE STUDY: A patient with third-degree burns and smoke inhalation-associated cyanide poisoning confirmed by measurements of whole blood cyanide was found in cardiac arrest and administered epinephrine and hydroxocobalamin (5 g + 5 g). Cardiac activity resumed, but the patient was declared brain dead on the third day of hospitalization when coma deteriorated to a shock state with refractory hypoxemia. Kidneys, heart, and liver were removed and transplanted into four patients. Gross pre-transplantation inspection of the donor organs and renal histology showed no evidence that hydroxocobalamin caused organ toxicity. Donor organs functioned normally through follow-up periods of several months. CONCLUSION: Anoxic cardiac arrest following acute cyanide poisoning treated with hydroxocobalamin (5 g + 5 g) was not a contraindication to organ transplantation after confirmed encephalic death in this patient.

Echography for nasogastric tube placement verification.

To report the interest of abdominal ultrasonography for confirming the appropriate location of nasogastric tube (NGT) in the stomach using a new dynamic test, and to illustrate the aspect of this test at ultrasonography. Clinical observation of a patient, images of abdominal ultrasonography and video of the stomach visualized by ultrasonography. We describe the video of a critically ill patient in whom, immediately after NGT insertion, aspiration of gastric liquid and instillation within the NGT was associated with ultrasonographic evidence of turbulences in the stomach. In addition to the direct visualization of the NGT in the stomach, ultrasonographic visualization of turbulences after aspiration and instillation of gastric liquid may allow to assess the appropriate positioning of the NGT.

[Extracorporeal CO2 removal as life support system for a severe organizing pneumonia]. / Épuration extracorporelle du CO2 pour suppléance d'une pneumonie organisée sévère.

INTRODUCTION: Acute lung injuries are usually found in intensive care unit. The diffuse alveolar damage (DAD) is the associated histological pattern and the most severe end-stage of the disease. Organizing pneumonia (OP), for which corticosteroids are the reference therapy, can mimic DAD. While postponing the response to treatment, to limit mechanical ventilation side effects, extracorporeal membrane oxygene can be proposed. We present a case of a severe OP for which extracorporeal CO2 removal (ECCO2R) is used as a bridge to recovery under corticosteroid therapy. CASE REPORT: In the context of a flu-like syndrome, the non-recovery of a lung impairment is reported to a severe OP. ECCO2R is applied when using an ultraprotective ventilation and while waiting for lung healing under corticosteroid. This strategy allowed successful recovery, early physical therapy and active mobilization. CONCLUSION: This observation presents the diagnostic and therapeutic difficulties of the lung parenchymental disease in intensive care. OP must be recognized. ECCO2R can be used in severe OP as a bridge to recovery while waiting for the corticosteroid efficacy.

Evaluation of Bag-Valve-Mask Ventilation in Manikin Studies: What Are the Current Limitations?

Introduction. Manikin-based studies for evaluation of ventilation performance show high heterogeneity in the analysis and experimental methods used as we pointed out in previous studies. In this work, we aim to evaluate these potential limitations and propose a new analysis methodology to reliably assess ventilation performance. Methods. One hundred forty healthcare providers were selected to ventilate a manikin with two adult self-inflating bags in random order. Ventilation parameters were analysed using different published analysis methods compared to ours. Results. Using different methods impacts the evaluation of ventilation efficiency which ranges from 0% to 45.71%. Our new method proved relevant and showed that all professionals tend to cause hyperventilation and revealed a significant relationship between professional category, grip strength of the hand keeping the mask, and ventilation performance (p = 0.0049 and p = 0.0297, resp.). Conclusion. Using adequate analysis methods is crucial to avoid many biases. Extrapolations to humans still have to be taken with caution as many factors impact the evaluation of ventilation performance. Healthcare professionals tend to cause hyperventilation with current devices. We believe this problem could be prevented by implementing monitoring tools in order to give direct feedback to healthcare professionals regarding ventilation efficiency and ventilatory parameter values.

[The ABLE study: A randomized controlled trial on the efficacy of fresh red cell units to improve the outcome of transfused critically ill adults]. / L'étude ABLE : un essai clinique randomisé sur l'effet de la durée d'entreposage des concentrés érythrocytaires transfusés en réanimation.

Red blood cell units are stored up to 42 days post-collection. The standard policy of blood banks is to deliver the oldest units in order to limit blood wastage. Many caregivers believe that giving fresh rather than old units can improve the outcome of their transfused patients. The ABLE study aims to check if the transfusion of red blood cell units stored seven days or less (fresh arm) improve the outcome of transfused critically ill adults compared to patients who received units delivered according to the standard delivery policy (control arm). From March 2009 to May 2014, 1211 patients were allocated to the fresh arm, 1219 to the control arm (length of storage: 6.1 ± 4.9 and 22.0 ± 8.4 days respectively, P<0.001). The primary outcome measure was 90-day all-cause mortality post-randomisation: there were 448 deaths (37.0%) in the fresh arm and 430 (35.3%) in the control arm (absolute risk difference: 1.7%; 95% confidence interval: -2.1% to 5.5%). In a survival analysis, the risk of death was higher in the fresh arm (hazard ratio: 1.1; 95%CI: 0.9 to 1.2), but the difference was not statistically significant (P=0.38). The same trend against the fresh arm was observed with all but one secondary outcome measures. The conclusion is that the transfusion of red blood cell units stored seven days or less does not improve the outcome of critically ill adults compared to the transfusion of units stored about three weeks (22.0 ± 8.4 days).

[Not Available]. / Épidémiologie descriptive de la brûlure dans un territoire de santé exemple du « territoire nord franche-comté ¼ durant l'année 2014.

This is an epidemiologic study of the need for Health Services for burns in the northern part of Franche Comté (north-east of France) along year 2014 (114 patients). Mean age was 26 years (8 month-81 years), one third of burns occurred in children below 15. Most burns take part in summer, around mealtime, in "school-free" days, at home and are scalds. Their surface is low (4,81%) and they are usually partial thickness ones. Patients are consulted in Emergency Department in 88,59% of the cases, and hospitalised thereafter in a Burns Unit (in Lyon more than Nancy or Metz) in 12,28%.

Use of pulsed-field gel electrophoresis as an epidemiologic tool during an outbreak of Pseudomonas aeruginosa lung infections in an intensive care unit.

OBJECTIVE: A retrospective study was performed to evaluate the use of DNA polymorphism analysis by pulsed-field gel electrophoresis (PFGE) in assessing the rate of exogenous contamination during an outbreak of Pseudomonas aeruginosa lung infections in an intensive care unit ICU. Another goal was to determine the risk factors, involved in the outbreak. DESIGN: Rectal swabs and tracheal secretions were cultured from all patients upon admission and thereafter once a week throughout their stay in the ICU. Resistance patterns were determined in all P. aeruginosa isolates. We determined the serotypes, pyocin types, plasmid profiles and total DNA macrorestriction patterns for isolates. The restriction fragment length polymorphism (RFLP) of Dra I total DNA digest was studied by PFGE. A retrospective case-control study was performed to determine the risk factors for P. aeruginosa bronchopulmonary colonization. SETTING: The study was carried out in the medical ICU of Besancon University Hospital (France). RESULTS: The typability, stability and reproducibility of phenotypic markers were not completely satisfactory. Only the RFLP profile satisfied all the criteria for a good typing technique. In four of the 17 patients, P. aeruginosa strains with the same DNA pattern were found. Among the previously reported risk factors for hospital-acquired bronchopulmonary infections, only invasive procedures were determined by multivariate analysis to be significant in our study group. The oropharynx and the bronchial tract are the most likely endogenous sources. CONCLUSION: PFGE-RFLP is a valuable tool for the epidemiologic study of P. aeruginosa. This typing method revealed that exogenous contamination is not always the major source of P. aeruginosa lung infections in mechanically ventilated patients in ICUs.

Predictive factors of death in primary lung cancer patients on admission to the intensive care unit.

OBJECTIVE: To assess the lung cancer patient's prognosis in the intensive care unit with early predictive factors of death. DESIGN: Retrospective study from July 1986 to February 1996. SETTING: Medical intensive care unit at a university hospital. PATIENTS: Fifty-seven patients with primary lung cancer admitted to our medical intensive care unit (MICU). MEASUREMENTS AND RESULTS: Data collection included demographic data (age, sex, underlying diseases, MICU admitting diagnosis) and evaluation of tumor (pathologic subtypes, metastases, lung cancer staging, treatment options). Three indexes were calculated for each patient: Karnofsky performance status, Simplified Acute Physiology Score (SAPS) II, and multisystem organ failure score (ODIN score). Mortality was high in the MICU: 66% of patients died during their MICU stay, and hospital mortality reached 75%. In multivariate analysis, acute pulmonary disease and Karnofsky performance status < 70 were associated with a poor MICU and post-MICU prognosis. For the survivors, long-term survival after MICU discharge depended exclusively on the severity of the lung cancer. CONCLUSIONS: We confirmed the high mortality rate of lung cancer patients admitted to the MICU. Two predictive factors of death in MICU were identified: performance status < 70 and acute pulmonary disease.

Inhaled nitric oxide in patients with pulmonary embolism.

OBJECTIVE: To describe the use of inhaled nitric oxide (NO) in four patients with severe pulmonary embolism. SETTING: The intensive care unit (ICU) of a university teaching hospital. PATIENTS: Four patients with severe pulmonary embolism on the basis of clinical, haemodynamic or blood-gas parameters received NO by inhalation either during spontaneous respiration (two cases) or while mechanically ventilated (two cases). INTERVENTIONS: Conventional management of pulmonary embolism in addition to the use of inhaled NO. MEASUREMENTS AND RESULTS: Description of clinical course, haemodynamic and gas-exchange data. Dose-response data are also described for three patients. CONCLUSIONS: We reported four cases of pulmonary embolism where the administration of inhaled NO resulted in an improvement in pulmonary haemodynamic and gas-exchange parameters. Two patients were weaned from NO and survived until discharged from the ICU. Inhaled NO might be a useful adjunct in pulmonary embolism to improve stability of the patient prior to thrombolysis or surgery.

Medication errors at the administration stage in an intensive care unit.

OBJECTIVE: To assess the type, frequency and potential clinical significance of medication-administration errors. DESIGN: Prospective study using the observation technique as described by the American Society of HealthSystem Pharmacists but eliminating the disguised aspect. SETTING: Medical intensive care unit (ICU) in a university hospital. PATIENTS AND PARTICIPANTS: 2009 medication administration interventions by nurses. INTERVENTIONS: Pharmacist-performed observation of preparation and administration of medication by nurses, comparison with the original medical order and comparison with the data available in the literature. MEASUREMENTS AND RESULTS: 132 (6.6% of 2009 observed events) errors were detected. Their distribution is as follows: 41 dose errors, 29 wrong rate, 24 wrong preparation technique, 19 physicochemical incompatibility, 10 wrong administration technique and 9 wrong time errors. No fatal errors were observed, but 26 of 132 errors were potentially life-threatening and 55 potentially significant. CONCLUSION: According to this first observation-based study of medication administration errors in a European ICU, these errors were due to deficiencies in the overall organisation of the hospital medication track, in patient follow-up and in staff training.

Oxygen tolerance in patients with acute respiratory failure.

OBJECTIVE: To search for a threshold of pulmonary oxygen toxicity in patients with acute respiratory failure. DESIGN: Retrospective study over a 10-year period. SETTING: Three intensive care units of two university hospitals. PATIENTS AND PARTICIPANTS: Seventy-four patients with acute respiratory failure ventilated continuously with a FIO2 > or = 0.9 for at least 48 h were selected. INTERVENTIONS: Information regarding status, scoring, diagnosis and therapeutic interventions upon admission and ICU course were extracted from the patients' charts. MEASUREMENTS AND RESULTS: We found that total exposure [mean (standard error of the mean)] to a FIO2 of 0.9 (TE 90) or more was 5.6 (1.1) days in the 17 survivors (S) versus 5.9 (0.5) days in the 57 non-survivors (D) (NS). Total exposure time to a FIO2 more than 0.5 (TE 50) was 16.5 (2.6) days in S and 11.2 (1) days in D (p < 0.05). The PaO2/FIO2 ratio became significantly higher in S only 5 days after beginning FIO2 of 0.9 or more. Hypoxemia was not frequent at the time of death, whereas in 70% of the non-survivors there were at least three organ failures in the last 48 h. In univariate analysis, the duration of exposure to FIO2 of 0.9 or more was not different in survivors and non-survivors, and the average total duration of exposure to FIO2 of more than 0.5 was even longer in survivors. In multivariate analysis, exposure shorter than 10 days to FIO2 more than 0.5 and exposure longer than 4 days to a FIO2 of 0.9 or more were significantly associated with death. However, despite a larger exposure to a FIO2 of 0.9 or more during the last 5 years of the study, the trend moved towards a higher survival rate during this period compared with the first 5 years of the study. CONCLUSIONS: Thus, our data provide circumstantial evidence that the lungs of patients with acute respiratory failure might exhibit some relative resistance to prolonged oxygen exposure. Therefore, it might be worthwhile carrying out a prospective study of different FIO2 strategies in such patients.

Endemicity, molecular diversity and colonisation routes of Pseudomonas aeruginosa in intensive care units.

OBJECTIVE: We carried out a prospective study to evaluate the endemicity of Pseudomonas aeruginosa in intensive care units (ICUs). Pulsed-field gel electrophoresis (PFGE) was used to determine the genotypes of P. aeruginosa isolates. This allowed us to determine the importance of cross-colonisation and the colonisation routes of P. aeruginosa. DESIGN: We screened epidemiological specimens (rectal swab, nose swab and tracheal aspiration) and routine clinical cultures from patients admitted to ICUs during a 2-year period, from 1st January, 1998, to 31st December, 1999. SETTING: The study was carried out in four separate adult ICUs located in the Franche-Comté region of France. These four units admitted a total of 1,500 patients per year. RESULTS: A total of 1686 specimens were collected from 473 patients; 122 of these patients were positive on admission, 351 became positive during hospitalisation. The overall incidence of P. aeruginosa was 15.7 cases per 100 patients and 15.1 cases per 1000 days of hospitalisation. Of 184 patients with at least one ICU-acquired positive clinical culture, 104 had been previously identified as carriers by a similar genotype. Typing of 208 non-replicate isolates revealed 101 major DNA patterns. Approximately 50% of P. aeruginosa carriage or colonisation/infection was acquired via cross-transmission; the other cases probably originated from endogenous sources. CONCLUSION: Cross-colonisation seems to play an important role in the general spread of P. aeruginosa in ICUs.

Cost-effectiveness of urinary dipsticks to screen asymptomatic catheter-associated urinary infections in an intensive care unit.

OBJECTIVE: To assess the cost-effectiveness of urinary dipsticks (UDs) to screen asymptomatic catheterized patients for quantitative urine. DESIGN: Prospective comparison of UD with quantitative urine culture (QUC) (reference technique) and cost-effectiveness analysis performed from the hospital's perspective. SETTING: Medical intensive care unit (ICU) of the Besançon University Hospital (France). PATIENTS AND PARTICIPANTS: All consecutive, asymptomatic, catheterized patients. INTERVENTIONS: Urinary dipsticks (Multistix 8-SG) were analyzed by the reflectance spectrophotometric method (Clinitek 50). Sensitivity (Se), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) of four combinations of the leukocyte (L) test pad and the nitrite (N) test pad were calculated: L and N, L or N, L alone and N alone. A micro-costing technique was used to determine the direct medical cost of each strategy. The calculated cost-effectiveness ratio was the incremental cost-effectiveness (ICE) ratio. MEASUREMENTS AND RESULTS: Three hundred thirty-nine urine samples taken from 144 patients were analyzed. The incidence of asymptomatic catheter-associated urinary tract infections (CAUTIs) was 31.3% (> or =10(5) organisms/ml). The L or N combination was the best detector of asymptomatic CAUTI: Se=87.2%, Sp=61.6%, PPV=30.6% and NPV=96.1%. The cost of QUC strategy and UD strategy was EUR 21.5 and EUR 12.6 per test, respectively. The ICE ratio of QUCs was EUR 69.5 per case of detected CAUTI. CONCLUSION: The UD is a cost-effective test for screening asymptomatic catheterized patients for quantitative urine culture in a medical ICU.

Epidemiological study of variations in beta-lactam antibiotic susceptibility of Pseudomonas aeruginosa in two intensive care units.

A six-month prospective study was carried out in the medical and surgical intensive care units (ICUs) at Besançon University Hospital to assess the frequency and risk factors for beta-lactam-resistant isolates of Pseudomonas aeruginosa. Clinical samples were screened for P. aeruginosa, and four antibiograms were distinguished using imipenem and ceftazidime, namely: fully susceptible (SS), imipenem-resistant (RS), ceftazidime-resistant (SR), and resistant to both (RR). DraI restriction fragment length polymorphism of isolates from different patients or with different resistance patterns but the same serotype was assessed by pulsed-field gel electrophoresis. One hundred and twenty-one isolates were obtained from 50 of 281 patients, 60.3% were fully susceptible. 19.8% imipenem-resistant, 13.2% ceftazidime-resistant, and 6.6% resistant to both. Antibiotic-resistance was independent of serotype. Twenty-two of 32 imipenem-resistant isolates from six patients were of the same DNA type, and six other isolates from four patients were of a second DNA type. On only one occasion did a clonally defined strain develop imipenem resistance. By contrast ceftazidime-resistant strains had differing DNA types, but had been originally ceftazidime-susceptible in seven of 12 patients. Reversion of imipenem resistant strains to susceptibility occurred in one patient, and of ceftazidime-resistant strains in five patients. Case-control studies identified prior antibiotic therapy as a risk factor in colonization with resistant strains. Resistance to imipenem followed imipenem therapy, and resistance to ceftazidime followed use of weakly anti-pseudomonal beta-lactam antibiotics. The major route of spread of imipenem-resistant strains was cross-colonization. Thus, assuming appropriate isolation, a carbapenem should be preferred to an extended-spectrum cephalosporin to treat pseudomonas infections in ICU patients.

[Osteochonroplastic tracheopathy associated with dermatomyositis: apropos of a case]. / Trachéopathie ostéochondroplastique associée à une dermatomyosite: à propos d'un cas.

We report a case of a 35 year-old-man with dermatomyositis associated with tracheopathia osteoplastica. The swallowing perturbation secondary to myositis and airway involvement by tracheopathia induced fatal outcome. Tracheopathia osteoplastica is a rare disease and occurs exclusively in men over the age of 50. The association of two rarest disease is not a fortuitous event. The common pathogenic factor may be, in this case, the occupational exposure to silicon.

[Diagnosis of post-traumatic pleural effusion]. / Diagnostic d'un épanchement pleural post-traumatique.

A rare case of post-traumatic pleural effusion is reported. A 19 year old male patient was admitted after a road traffic accident with a scalp wound, femoral shaft fracture and haematuria related to a ruptured bladder. Shortly after extubation following bladder surgical repair, the patient had to be reintubated because of acute respiratory failure. A large left-sided pleural effusion was then diagnosed. The liquid was sero-haematic and contained a high concentration of creatinine (839 mumol.l-1). Thoracic CT scan and intravenous urography displayed a left epirenal collection and a dilatation of the upper urinary tract with rupture of the renal pelvis. The surgical treatment of this urinothorax consisted of the rupture repair of the posterior diaphragm and of the urinary tract.

[Purulent pleurisy caused by anaerobic bacteria. A retrospective study of 19 cases]. / Pleurésies purulentes à anaérobies. Etude rétrospective de 19 cas.

A retrospective clinical, biological, radiological and evolutive study of 19 cases of pleural empyema caused by anaerobic organisms diagnosed between 1980 and 1986 was carried out. These 19 cases accounted for 30.6 p. 100 of all cases of pleural empyema diagnosed during the same period. A local or general contributory factor was found in all patients; false passage, gastrointestinal pathology and buccal or dental diseases were the most frequent aetiological circumstances. The clinical picture was rather torpid, with a body temperature below 38 degrees C in 42 p. 100 of the cases, which delayed the diagnosis: the mean time interval between onset and diagnosis was 20 days. In nearly one half of the cases, blood stained expectoration was present and air-fluid levels were visualized at standard radiography and computerized tomography, which is the best exploratory method to evaluate the size and appearance of the pleural lesion, to guide percutaneous drainage and later to assess possible sequelae. The predominant anaerobic flora consisted of Gram-positive cocci and Bacteroides spp; in 70 p. 100 of the cases the anaerobic organism(s) was (were) sensitive to penicillin G. The course of the disease was favourable in all patients. Surgery was performed in 3 of the 19 patients on account of chest wall gangrene due to Clostridium perfringens in 1 case and of the presence of multiple fluid pockets making drainage ineffective in 2 cases.