Gene screening of Wharton's jelly derived stem cells

Stem cells are the most powerful candidate for the treatment of various diseases. Suitable stem cell source should be harvested with minimal invasive procedure, found in great quantity, and transplanted with no risk of immune response and tumor formation. Fetal derived stem cells have been introduced as an excellent alternative to adult and embryonic stem cells use, but unfortunately, their degree of "stemness" and molecular characterization is still unclear. Several studies have been performed deciphering whether fetal stem cells meet the needs of regenerative medicine. We believe that a transcriptomic screening of Wharton's jelly stem cells will bring insights on cell population features.

Chromosomal context and epigenetic mechanisms control the efficacy of genome editing by rare-cutting designer endonucleases

The ability to specifically engineer the genome of living cells at precise locations using rare-cutting designer endonucleases has broad implications for biotechnology and medicine, particularly for functional genomics, transgenics and gene therapy. However, the potential impact of chromosomal context and epigenetics on designer endonuclease-mediated genome editing is poorly understood. To address this question, we conducted a comprehensive analysis on the efficacy of 37 endonucleases derived from the quintessential I-CreI meganuclease that were specifically designed to cleave 39 different genomic targets. The analysis revealed that the efficiency of targeted mutagenesis at a given chromosomal locus is predictive of that of homologous gene targeting. Consequently, a strong genome-wide correlation was apparent between the efficiency of targeted mutagenesis (≤ 0.1% to ≈ 6%) with that of homologous gene targeting (≤ 0.1% to ≈ 15%). In contrast, the efficiency of targeted mutagenesis or homologous gene targeting at a given chromosomal locus does not correlate with the activity of individual endonucleases on transiently transfected substrates. Finally, we demonstrate that chromatin accessibility modulates the efficacy of rare-cutting endonucleases, accounting for strong position effects. Thus, chromosomal context and epigenetic mechanisms may play a major role in the efficiency rare-cutting endonuclease-induced genome engineering.

Feasibility, limits and problems of clinical studies in Intensive Care Unit

In critical care medicine there is still a paucity of evidence on how to manage most of the clinical problems commonly encountered in critically ill patients. Randomized controlled trials (RCTs) are the most powerful instruments to evaluate the efficacy of a therapeutic intervention and to generate evidence for clinical practice. Unfortunately, the design and conduct of RCTs in our field are particularly complicated, because of some intrinsic and structural problems (e.g. lack of reliable nosography, concomitant use of different therapies, problems in the definition of end-points besides mortality) that will be discussed in this review. Further challenges are represented by the lack of tradition of large ICU networks, difficulties in linking or integrating physiologic and therapeutic objectives in designing clinical protocols, scarcity of independent or non-profit funds. A particularly stimulating opportunity of development is represented also by the relationship of critical care to EBM. Because of the above problems, metanalyses could be less informative than in other areas of medicine, as they are based on few trials which are often contradictory and of unsatisfactory quality. Few suggestions are formulated which could help looking forwards.

Are institutional review boards effective in safeguarding patients in intensive care units?

Institutional Review Boards have been recently audited in the US, and a great deal of concerns and criticisms appeared in the medical literature and the lay press. Globally, these comments questioned the efficiency of Institutional Review Boards in fulfilling their basic mission, the protection of patients subjected to biomedical research. Vulnerable populations, such as psychiatric and incompetent patients, were particularly identified. In intensive care units, conducting research in critically ill patients unable to give informed consent themselves remains a hot issue. Several possibilities have been proposed and assessed in the recent past: pre-emptive (global) consent, proxy consent from a surrogate, deferred consent, and, more recently, waiver of consent for emergency research. Obviously, the inability to deal with this major obstacle (i.e. obtaining consent from incompetent patients) would lead to the cessation of any research in intensive care units, which is hardly acceptable and certainly unethical. Recent published studies have reported over-mortality in treatment groups, posing new questions: who should be informed of those failures, and when? What is the role of Institutional Review Boards in preventing such an issue? What type of indemnity should be proposed to the family of deceased patients during a trial?

Toxicity assays in nanodrops combining bioassay and morphometric endpoints

Background

Improved chemical hazard management such as REACH policy objective as well as drug ADMETOX prediction, while limiting the extent of animal testing, requires the development of increasingly high throughput as well as highly pertinent in vitro toxicity assays.

Methodology

This report describes a new in vitro method for toxicity testing, combining cell-based assays in nanodrop Cell-on-Chip format with the use of a genetically engineered stress sensitive hepatic cell line. We tested the behavior of a stress inducible fluorescent HepG2 model in which Heat Shock Protein promoters controlled Enhanced-Green Fluorescent Protein expression upon exposure to Cadmium Chloride (CdCl₂), Sodium Arsenate (NaAsO₂) and Paraquat. In agreement with previous studies based on a micro-well format, we could observe a chemical-specific response, identified through differences in dynamics and amplitude. We especially determined IC50 values for CdCl₂ and NaAsO₂, in agreement with published data. Individual cell identification via image-based screening allowed us to perform multiparametric analyses.

Conclusions

Using pre/sub lethal cell stress instead of cell mortality, we highlighted the high significance and the superior sensitivity of both stress promoter activation reporting and cell morphology parameters in measuring the cell response to a toxicant. These results demonstrate the first generation of high-throughput and high-content assays, capable of assessing chemical hazards in vitro within the REACH policy framework.

Participation of French general practitioners in end-of-life decisions for their hospitalised patients

BACKGROUND AND OBJECTIVE

Assuming the hypothesis that the general practitioner (GP) can and should be a key player in making end-of-life decisions for hospitalised patients, perceptions of GPs' role assigned to them by hospital doctors in making withdrawal decisions for such patients were surveyed.

DESIGN

Questionnaire survey.

SETTING

Urban (districts located near Paris) and rural (southern France) areas.

PARTICIPANTS

GPs.

RESULTS

The response rate was 32.2% (161/500), and it was observed that 70.8% of respondents believed that their participation in withdrawal decisions for their hospitalised patients was essential, whereas 42.1% believed that the hospital doctors were sufficiently skilled to make withdrawal decisions without input from the GPs. Most respondents were found to believe that they had the necessary skills (91.9%) and enough time (87.6%) to participate in withdrawal decisions. The last case of treatment withdrawal in hospital for one of their patients was described by 40% (65/161) of respondents, of whom only 40.0% (26/65) believed that they had participated actively in the decision process. The major factors in the multivariate analysis were the GP's strong belief that his or her participation was essential (p = 0.01), information on admission of the patient given to the GP by the hospital department (p = 0.007), rural practice (p = 0.03), visit to the patient dying in hospital (p = 0.02) and a request by the family to be kept informed about the patient (p = 0.003).

CONCLUSION

Strong interest was evinced among GPs regarding end-of-life issues, as well as considerable experience of patients dying at home. As GPs are more closely corrected to patients' families, they may be a good choice for third-party intervention in making end-of-life decisions for hospitalised patients.

Head and neck squamous cell carcinoma transcriptome analysis by comprehensive validated differential display

Head and neck squamous cell carcinoma (HNSCC) is common worldwide and is associated with a poor rate of survival. Identification of new markers and therapeutic targets, and understanding the complex transformation process, will require a comprehensive description of genome expression, that can only be achieved by combining different methodologies. We report here the HNSCC transcriptome that was determined by exhaustive differential display (DD) analysis coupled with validation by different methods on the same patient samples. The resulting 820 nonredundant sequences were analysed by high throughput bioinformatics analysis. Human proteins were identified for 73% (596) of the DD sequences. A large proportion (>50%) of the remaining unassigned sequences match ESTs (expressed sequence tags) from human tumours. For the functionally annotated proteins, there is significant enrichment for relevant biological processes, including cell motility, protein biosynthesis, stress and immune responses, cell death, cell cycle, cell proliferation and/or maintenance and transport. Three of the novel proteins (TMEM16A, PHLDB2 and ARHGAP21) were analysed further to show that they have the potential to be developed as therapeutic targets.

Le projet de loi relative aux droits des malades et à la fin de vie

A bill about Patients' rights and the end of life was adopted unanimously by the National Assembly on November 30, 2004. Article 1 provides that the physician is not obligated to continue treatment "when the latter appears futile, disproportional and has no effect other than artificially maintaining the patient's life". Article 2 recognizes that painkillers administered at high doses to terminally ill patients may as a side effect "shorten the patient's life". Conscious patients and the families of unconscious patients must be so informed, and the discussion must be mentioned in the patient's file. Physicians must respect their patients' refusal of treatment, even in life-threatening situations. On the other hand, patients who are not terminally ill must await the expiration of a mandatory waiting period before the physicians must comply with their wishes to refuse care. Article 3 specifies that any treatment can be withheld or withdrawn, including artificial nutrition. The law specifies that it is applicable in 4 different sets of situations: for patients who are or are not terminally and for those who are or are not conscious. Article 9 makes clear that futile treatment of unconscious patients can be withheld or withdrawn. Article 7 specifies that adults may draw up advance directives to indicate their wishes for their end of life and their desires regarding the withholding or withdrawal of treatment. Withholding or withdrawing active treatment is authorized under 3 conditions: the consent from the patient, or if he or she is unconscious, the approval of the health-care proxy, or a family member or close friend if the patient is unconscious; the inclusion of the decision in the patient's medical file, and a group decision-making process.

Loss of HOP tumour suppressor expression in head and neck squamous cell carcinoma

We report that homeodomain-only protein (HOP) is expressed in the suprabasal layer of normal upper aerodigestive tract epithelium and expression strongly decreases in hypopharyngeal carcinoma. Interestingly, HOP has very recently been shown to be a tumour suppressor involved in differentiation, suggesting that HOP may have a similar role in head and neck squamous cell carcinoma (HNSSC).

Successful weaning from mechanical ventilation after coronary angioplasty

Weaning failure can be caused by myocardial ischaemia during the switch from mechanical to spontaneous ventilation. We report ischaemic left ventricular failure and ischaemic mitral insufficiency during weaning. Angiography showed that the coronary vessels were stenosed. Transluminal angioplasty made weaning possible. We conclude that acute ischaemic mitral insufficiency may contribute to cardiac failure during weaning and that angioplasty, by reversing it, can allow successful weaning.

Identification of genes associated with tumorigenesis and metastatic potential of hypopharyngeal cancer by microarray analysis

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer among men in the developed world. There is a need, for both clinical and scientific reasons, to find markers to identify patients with aggressive disease as early as possible, and to understand the events leading to malignant transformation and susceptibility to metastasis. We report the first large-scale gene expression analysis of a unique HNSCC location, the hypopharynx. Four normal and 34 tumour samples were analysed with 12 600 gene microarrays. Clusters of differentially expressed genes were identified in the chromosomal regions 3q27.3, 17q21.2-q21.31, 7q11.22-q22.1 and 11q13.1-q13.3, which, interestingly, have already been identified by comparative genomic hybridization (CGH) as major regions of gene amplification. We showed that six overexpressed genes (EIF4G1, DVL3, EPHB4, MCM7, BRMS1 and SART1) located in these regions are indeed amplified. We report 119 genes that are highly differentially expressed between 'early' tumours and normal samples. Of these, we validated by quantitative PCR six novel poorly characterized genes. These genes are potential new markers of HNSCC. Comparing patients with relatively nonaggressive and aggressive tumours (without or with clinical evidence of metastasis 3 years after surgery), we identified 164 differentially expressed genes potentially involved in the acquisition of metastatic potential. This study contributes to the understanding of HNSCC, staging patients into prognostic groups and identifying high-risk patients who may benefit from more aggressive treatment.

Differential expression profiling of head and neck squamous cell carcinoma (HNSCC)

Head and neck squamous cell carcinoma (HNSCC) is the fifth most common cancer in men with an incidence of about 780 000 new cases per year worldwide and a poor rate of survival. There is a need for a better understanding of HNSCC, for the development of rational targeted interventions and to define new prognostic or diagnostic markers. To address these needs, we performed a large-scale differential display comparison of hypopharyngeal HNSCCs against histologically normal tissue from the same patients. We have identified 70 genes that exhibit a striking difference in expression between tumours and normal tissues. There is only a limited overlap with other HNSCC gene expression studies that have used other techniques and more heterogeneous tumour samples. Our results provide new insights into the understanding of HNSCC. At the genome level, a series of differentially expressed genes cluster at 12p12–13 and 1q21, two hotspots of genome disruption. The known genes share functional relationships in keratinocyte differentiation, angiogenesis, immunology, detoxification, and cell surface receptors. Of particular interest are the 13 ‘unknown’ genes that exist only in EST, theoretical cDNA and protein databases, or as chromosomal locations. The differentially expressed genes that we have identified are potential new markers and therapeutic targets.

Death of terminally ill patients on a stretcher in the emergency department: a French speciality?

OBJECTIVES

To determine the frequency, modalities of admission and management of terminally ill patients who died on a stretcher in an emergency department (ED).

DESIGN AND SETTING

Retrospective study in an ED of a university hospital.

METHODS

Current place of residence, modalities of admission in ED, mortality probability scores and type of management were extracted for each patient in the terminal stage of chronic disease who died on a stretcher in our ED during a 3year period.

RESULTS

Of 159 deaths observed in the ED, 56 (35%) concerned terminally ill patients. The illness was a malignancy in 22 cases, a neurological disease in 22 cases and a cardiopulmonary disease in 12 cases. Most of the patients were referred by their regular doctor. Seventy-two percent of the malignancy patients were living at home, 55% of the neurological patients came from nursing facilities and 58% of the cardio-respiratory patients came from the hospital. In 73%, 83% and 23% of the patients with malignancy, cardiopulmonary and neurological diseases, respectively, admission was related to the evolution of the chronic disease. Severity of illness on admission was similar whatever the disease. Request for compassionate end-of-life care was expressed in only 12.5%. At the ED, 91% of patients with neurological diseases received palliative support care. Supportive therapy was undertaken in one third of patients with malignancy or cardiopulmonary disease.

CONCLUSION

An ED may be used as a place for dying for some terminally ill patients. This could be related to the legal opposition to withdrawal or withholding of life-support therapies as well as the absence of guidelines from scientific bodies.

Symptoms of anxiety and depression in family members of intensive care unit patients: ethical hypothesis regarding decision-making capacity

OBJECTIVE

Anxiety and depression may have a major impact on a person's ability to make decisions. Characterization of symptoms that reflect anxiety and depression in family members visiting intensive care patients should be of major relevance to the ethics of involving family members in decision-making, particularly about end-of-life issues.

DESIGN

Prospective multicenter study.

SETTING

Forty-three French intensive care units (37 adult and six pediatric); each unit included 15 patients admitted for longer than 2 days.

PATIENTS

Six hundred thirty-seven patients and 920 family members.

INTERVENTIONS

Intensive care unit characteristics and data on the patient and family members were collected. Family members completed the Hospital Anxiety and Depression Scale to allow evaluation of the prevalence and potential factors associated with symptoms of anxiety and depression.

MEASUREMENTS AND MAIN RESULTS

Of 920 Hospital Anxiety and Depression Scale questionnaires that were completed by family members, all items were completed in 836 questionnaires, which formed the basis for this study. The prevalence of symptoms of anxiety and depression in family members was 69.1% and 35.4%, respectively. Symptoms of anxiety or depression were present in 72.7% of family members and 84% of spouses. Factors associated with symptoms of anxiety in a multivariate model included patient-related factors (absence of chronic disease), family-related factors (spouse, female gender, desire for professional psychological help, help being received by general practitioner), and caregiver-related factors (absence of regular physician and nurse meetings, absence of a room used only for meetings with family members). The multivariate model also identified three groups of factors associated with symptoms of depression: patient-related (age), family-related (spouse, female gender, not of French descent), and caregiver-related (no waiting room, perceived contradictions in the information provided by caregivers).

CONCLUSIONS

More than two-thirds of family members visiting patients in the intensive care unit suffer from symptoms of anxiety or depression. Involvement of anxious or depressed family members in end-of-life decisions should be carefully discussed.

French intensivists do not apply American recommendations regarding decisions to forgo life-sustaining therapy

OBJECTIVE

Recommendations for making and implementing decisions to forgo life-sustaining therapy in intensive care units have been developed in the United States, but the extent that they are realized in practice has yet to be measured.

DESIGN

Prospective, multicenter, 4-wk study. For each patient with an implemented decision to forgo life-sustaining therapy, the deliberation and decision implementation procedures were recorded.

SETTING

French intensive care units.

PATIENTS

All consecutive patients admitted to 26 French intensive care units.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 1,009 patients admitted, 208 died in the intensive care unit. A decision to forgo life-sustaining therapy was implemented in 105 patients. The number of supportive treatments forgone was 2.3 +/- 1.7 per patient. Decisions to forgo sustaining therapy were preceded by 3.5 +/- 2.5 deliberation sessions. Proxies were informed of the deliberations in 62 (59.1%) cases but participated in only 18 (17.1%) decisions. The patient's perception of his or her quality of life was rarely evaluated (11.5%), and only rarely did the decision involve evaluating the patient's wishes (7.6%), the patient's religious values (7.6%), or the cost of treatment (7.6%). Factors most frequently evaluated were medical team advice (95.3%), predicted reversibility of acute disease (90.5%), underlying disease severity (83.9%), and the patient's quality of life as evaluated by caregivers (80.1%).

CONCLUSIONS

A decision to withhold or withdraw life-sustaining therapy was implemented for half the patients who died in the French intensive care units studied. In many cases, the decision was taken without regard for one or more factors identified as relevant in U.S. guidelines.

Accuracy of pulse oximetry in the intensive care unit

OBJECTIVE

Pulse oximetry (SpO2) is a standard monitoring device in intensive care units (ICUs), currently used to guide therapeutic interventions. Few studies have evaluated the accuracy of SpO2 in critically ill patients. Our objective was to compare pulse oximetry with arterial oxygen saturation (SaO2) in such patients, and to examine the effect of several factors on this relationship.

DESIGN

Observational prospective study.

SETTING

A 26-bed medical ICU in a university hospital.

PATIENTS

One hundred two consecutive patients admitted to the ICU in whom one or serial arterial blood gas analyses (ABGs) were performed and a reliable pulse oximeter signal was present.

INTERVENTIONS

For each ABG, we collected SaO2, SpO2, the type of pulse oximeter, the mode of ventilation and requirement for vasoactive drugs.

MEASUREMENTS AND RESULTS

Three hundred twenty-three data points were collected. The mean difference between SpO2 and SaO2 was -0.02% and standard deviation of the differences was 2.1%. From one sample to another, the fluctuations in SpO2 to arterial saturation difference indicated that SaO2 could not be reliably predicted from SpO2 after a single ABG. Subgroup analysis showed that the accuracy of SpO2 appeared to be influenced by the type of oximeter, the presence of hypoxemia and the requirement for vasoactive drugs. Finally, high SpO2 thresholds were necessary to detect significant hypoxemia with good sensitivity.

CONCLUSION

Large SpO2 to SaO2 differences may occur in critically ill patients with poor reproducibility of SpO2. A SpO2 above 94% appears necessary to ensure a SaO2 of 90%.

Alveolar derecruitment at decremental positive end-expiratory pressure levels in acute lung injury: comparison with the lower inflection point, oxygenation, and compliance

We examined the hypothesis that recording multiple elastic pressure-volume (Pel/V) curves and calculating alveolar derecruitment (V(DER)) induced by decreasing positive end-expiratory pressure (PEEP) may allow determination of alveolar closing pressures, thus helping to select the optimal PEEP level. V(DER) measured in 16 patients with acute lung injury (ALI) was compared with the lower inflection point (LIP) and oxygenation changes. A modified automated method was used to record multiple Pel/V curves at low constant flow. PEEP was decreased in 5-cm H(2)O steps, from 20 or 15 cm H(2)O to 0 cm H(2)O (ZEEP). V(DER) was the volume loss between the curves recorded from PEEP and from ZEEP at the same Pel. Derecruitment occurred at each PEEP decrement, being spread almost uniformly over the 20/15 to 0 cm H(2)O range. V(DER) was not correlated with LIP. V(DER) changes correlated with Pa(O(2))/FI(O(2)) changes (rho = 0.6, p = 0.02). Linear compliance at ZEEP was correlated to V(DER) at PEEP 15 cm H(2)O (rho = 0.9, p = 0.001), suggesting that compliance above LIP may reflect the amount of recruitable lung. Thus, alveolar closure in ALI occurs over a wide range of pressures, and LIP is a poor predictor of alveolar closure.

Decision-making capacity and surrogate designation in French ICU patients

OBJECTIVE

To evaluate the capacity and willingness of French-speaking patients to designate a surrogate within 24 h of their ICU admission. French laws fail to indicate what should be done when an otherwise legally competent patient transiently loses his decision-making capacity.

DESIGN

Surrogate designation was prospectively evaluated during two study periods. Only conscious patients were assessed using the Glasgow Come Score in the first study period, and all admitted patients were assessed in the second period. Decision-making capacity was evaluated using the Mini Mental Status Examination (MMSE) in the second study period.

SETTING

Twenty six-bed intensive care unit (ICU) in a French teaching hospital.

PATIENTS AND PARTICIPANTS

Over a 8-month period 495 patients were included in the study, 415 in the first study period and 80 in the second.

MEASUREMENTS AND RESULTS

Of the 495 patients 185 (37.3%) were interviewed, and 62.7% designated a surrogate. The surrogate was the spouse in 50% of cases and a child in 28.4%. Only 25.8% were considered to have decision-making capacity; 78.1% of competent patients and 28% of the patients without decision-making capacity agreed to designate a surrogate.

CONCLUSIONS

Surrogate designation by a patient should be evaluated in the light of the decision-making capacity of the patient. The traditional French paternalism still practiced by many French physicians appears out of tune with the wishes of their patients. We suggest that there is a need for developing a simple and effective tool for assessing decision-making capacity in ICU patients.

Spontaneous hemomediastinum complicating steroid-induced mediastinal lipomatosis

Spontaneous hemomediastinum is a rare event, occurring in association with bleeding disorders, intratumoral bleeding, or following an abrupt increase in intrathoracic pressure. We report the case of a patient with systemic lupus erythematosus, nephrotic syndrome, and renal failure, in whom mediastinal lipomatosis (ML) developed following increased corticosteroid therapy. Anticoagulant therapy likely precipitated a massive spontaneous hemomediastinum secondary to diffuse hemorrhage of mediastinal fat, which required emergency decompressive surgery. Steroid-induced ML is common and usually well tolerated, but clinicians should be aware of its potential risk of bleeding when associated with anticoagulant therapy. This case further emphasizes the bleeding complications of treatment with low-molecular-weight heparin in patients with renal failure.

Influence of tidal volume on alveolar recruitment. Respective role of PEEP and a recruitment maneuver

Both reduction in tidal volume (VT) and alveolar recruitment may be important to limit ventilator-associated lung injury during mechanical ventilation of patients with the acute respiratory distress syndrome (ARDS). The aim of this study was to assess the risk of alveolar derecruitment associated with VT reduction from 10 to 6 ml/kg. Whether this VT-related derecruitment could be reversed, either by a recruitment maneuver or by an increase in positive end-expiratory pressure (PEEP) level, was also investigated. Fifteen patients with ARDS were successively ventilated using conventional VT (CVT = 10 +/- 1 ml/kg) and low VT (LVT = 6 +/- 1 ml/ kg); total PEEP (PEEPtot) was individually set at the lower inflection point (Plip) of the pressure-volume curve (PEEPtot = 11 +/- 4 cm H(2)O). Pressure-volume curves were recorded from zero PEEP (ZEEP) and from PEEP, and recruited volume (Vrec) was calculated as the volume difference between the two curves for a given pressure. Despite a similar PEEPtot, Vrec was significantly lower with LVT than with CVT, indicating low VT-induced alveolar derecruitment. Reduction in VT was associated with a reduced Sa(O(2)). In 10 patients, Vrec was also measured before and after a recruitment maneuver (two sustained inflations at 45 cm H(2)O), and after an increase in PEEP (by 4 cm H(2)O). Low VT-induced derecruitment was reversed by a recruitment maneuver and by increasing PEEP. We conclude that a reduction in VT could be responsible for alveolar derecruitment, which may be transiently reversed by a reexpansion maneuver or prevented by a PEEP increase above Plip.

Effects of hydroxyethylstarch and gelatin on renal function in severe sepsis: a multicentre randomised study

BACKGROUND

Hydroxyethylstarch used for volume restoration in brain-dead kidney donors has been associated with impaired kidney function in the transplant recipients. We undertook a multicentre randomised study to assess the frequency of acute renal failure (ARF) in patients with severe sepsis or septic shock treated with hydroxyethylstarch or gelatin.

METHODS

Adults with severe sepsis or septic shock were enrolled prospectively in three intensive-care units in France. They were randomly assigned 6% hydroxyethylstarch (200 kDa, 0.60-0.66 substitution) or 3% fluid-modified gelatin. The primary endpoint was ARF (a two-fold increase in serum creatinine from baseline or need for renal replacement therapy). Analyses were by intention to treat.

FINDINGS

129 patients were enrolled over 18 months. Severity of illness and serum creatinine (median 143 [IQR 88-203] vs 114 [91-175] micromol/L) were similar at baseline in the hydroxyethylstarch and gelatin groups. The frequencies of ARF (27/65 [42%] vs 15/64 [23%], p=0.028) and oliguria (35/62 [56%] vs 23/63 [37%], p=0.025) and the peak serum creatinine concentration (225 [130-339] vs 169 [106-273] micromol/L, p=0.04) were significantly higher in the hydroxyethylstarch group than in the gelatin group. In a multivariate analysis, risk factors for acute renal failure included mechanical ventilation (odds ratio 4.02 [95% CI 1.37-11.8], p=0.013) and use of hydroxyethylstarch (2.57 [1.13-5.83], p=0.026).

INTERPRETATIONS

The use of this preparation of hydroxyethylstarch as a plasma-volume expander is an independent risk factor for ARF in patients with severe sepsis or septic shock.

Liquid ventilation

Partial liquid ventilation (PLV) developed considerably in the clinical and experimental fields during the past few years. In addition to improved oxygenation and lung mechanics by perfluorocarbon (PFC) administration, recent animal studies have tried to optimize PLV by evaluating the most appropriate ventilatory mode to use during PLV and by adjusting the best level of positive end-expiratory pressure (PEEP). Other pathophysiological aspects of acute lung injury that may be positively affected by liquid ventilation have been studied, including regional blood flow redistribution, reduction in ventilator-induced lung injury, and antiinflammatory properties of PFC. Although the precise dosing of PFC is debated, evidence from several experimental studies supports the use of smaller doses of PFC because larger doses increase the occurrence of baro- and volutrauma. In the clinical field, after promising data from preliminary studies, an international randomized controlled trial is on the verge of completion.

Withholding and withdrawal of life support in intensive-care units in France: a prospective survey. French LATAREA Group

BACKGROUND

In France, there are no guidelines available on withholding and withdrawal of life-sustaining treatments, and information on the frequency of such decisions is scarce.

METHODS

We undertook a prospective 2-month survey in 113, of a total of 220, intensive-care units (ICUs) in France to study the frequency of, and processes leading to, decisions to withhold and withdraw life-sustaining treatments.

FINDINGS

Life-supporting therapies were withheld or withdrawn in 807 (11.0%) of 7309 patients (withholding in 336 [4.6%] and withdrawal in 471 [6.4%], preceded in 358 by withholding). Of 1175 deaths in ICU, 628 (53%) were preceded by a decision to limit life-supporting therapies. Futility and poor expected quality of life were the most frequently cited reasons. Decisions were strongly correlated with the simplified acute physiological score, but an independent centre effect persisted after adjustment for this score. Decisions were mostly taken by all the ICU medical staff, with (54%) or without (34%) the nursing staff; however, a single physician made decisions in 12% of cases. The patient's family was involved in the decision-making process in 44% of cases. The patient's willingness to limit his or her own care was known in only 8% of the cases; only 0.5% of the patients were involved in decisions.

INTERPRETATION

Withholding and withdrawal of life-support therapies are widely practised in French ICUs, despite their prohibition by the French legislation. The lack of an official statement from French scientific bodies may explain several limitations on the various steps of the decision-making process.

Meeting the needs of intensive care unit patient families: a multicenter study

Intensive care unit (ICU) caregivers should seek to develop collaborative relationships with their patients' family members, based on an open exchange of information and aimed at helping family members cope with their distress and allowing them to speak for the patient if necessary. We conducted a prospective multicenter study of family member satisfaction evaluated using the Critical Care Family Needs Inventory. Forty-three French ICUs participated in the study. ICU characteristics, patient and family member demographics, and data on satisfaction were collected. Factors associated with satisfaction were identified using a Poisson regression model. A total of 637 patients were included in the study, and 920 family members completed the questionnaire. Seven predictors of family satisfaction were found: one family-related factor, namely, family of French descent and six caregiver-related factors, namely, no perceived contradictions in information given by caregivers; information provided by a junior physician; patient to nurse ratio </= 3; knowledge of the specific role of each caregiver; help from the family's own doctor; and sufficient time spent giving information. Predictors of satisfaction are amenable to intervention and deserve to be investigated further with the goal of improving the satisfaction of ICU patients' family members.

Treatment of acute hypoxemic nonhypercapnic respiratory insufficiency with continuous positive airway pressure delivered by a face mask: A randomized controlled trial

CONTEXT

Continuous positive airway pressure (CPAP) is widely used in the belief that it may reduce the need for intubation and mechanical ventilation in patients with acute hypoxemic respiratory insufficiency.

OBJECTIVE

To compare the physiologic effects and the clinical efficacy of CPAP vs standard oxygen therapy in patients with acute hypoxemic, nonhypercapnic respiratory insufficiency.

DESIGN, SETTING, AND PATIENTS

Randomized, concealed, and unblinded trial of 123 consecutive adult patients who were admitted to 6 intensive care units between September 1997 and January 1999 with a PaO(2)/FIO(2) ratio of 300 mm Hg or less due to bilateral pulmonary edema (n = 102 with acute lung injury and n = 21 with cardiac disease).

INTERVENTIONS

Patients were randomly assigned to receive oxygen therapy alone (n = 61) or oxygen therapy plus CPAP (n = 62).

MAIN OUTCOME MEASURES

Improvement in PaO(2)/FIO(2) ratio, rate of endotracheal intubation at any time during the study, adverse events, length of hospital stay, mortality, and duration of ventilatory assistance, compared between the CPAP and standard treatment groups.

RESULTS

Among the CPAP vs standard therapy groups, respectively, causes of respiratory failure (pneumonia, 54% and 55%), presence of cardiac disease (33% and 35%), severity at admission, and hypoxemia (median [5th-95th percentile] PaO(2)/FIO(2) ratio, 140 [59-288] mm Hg vs 148 [62-283] mm Hg; P =.43) were similarly distributed. After 1 hour of treatment, subjective responses to treatment (P<.001) and median (5th-95th percentile) PaO(2)/FIO(2) ratios were greater with CPAP (203 [45-431] mm Hg vs 151 [73-482] mm Hg; P =.02). No further difference in respiratory indices was observed between the groups. Treatment with CPAP failed to reduce the endotracheal intubation rate (21 [34%] vs 24 [39%] in the standard therapy group; P =.53), hospital mortality (19 [31%] vs 18 [30%]; P =.89), or median (5th-95th percentile) intensive care unit length of stay (6.5 [1-57] days vs 6.0 [1-36] days; P =.43). A higher number of adverse events occurred with CPAP treatment (18 vs 6; P =.01).

CONCLUSION

In this study, despite early physiologic improvement, CPAP neither reduced the need for intubation nor improved outcomes in patients with acute hypoxemic, nonhypercapnic respiratory insufficiency primarily due to acute lung injury. JAMA. 2000;284:2352-2360.

Association of noninvasive ventilation with nosocomial infections and survival in critically ill patients

CONTEXT

Invasive life-support techniques are a major risk factor for nosocomial infection. Noninvasive ventilation (NIV) can be used to avoid endotracheal intubation and may reduce morbidity among patients in intensive care units (ICUs).

OBJECTIVE

To determine whether the use of NIV is associated with decreased risk of nosocomial infections and improved survival in everyday clinical practice among patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) or hypercapnic cardiogenic pulmonary edema (CPE).

DESIGN AND SETTING

Matched case-control study conducted in the medical ICU of a French university hospital from January 1996 through March 1998.

PATIENTS

Fifty patients with acute exacerbation of COPD or severe CPE who were treated with NIV for at least 2 hours and 50 patients treated with mechanical ventilation between 1993 and 1998 (controls), matched on diagnosis, Simplified Acute Physiology Score II, Logistic Organ Dysfunction score, age, and no contraindication to NIV.

MAIN OUTCOME MEASURES

Rates of nosocomial infections, antibiotic use, lengths of ventilatory support and of ICU stay, ICU mortality, compared between cases and controls.

RESULTS

Rates of nosocomial infections and of nosocomial pneumonia were significantly lower in patients who received NIV than those treated with mechanical ventilation (18% vs 60% and 8% vs 22%; P<.001 and P =.04, respectively). Similarly, the daily risk of acquiring an infection (19 vs 39 episodes per 1000 patient-days; P =.05), proportion of patients receiving antibiotics for nosocomial infection (8% vs 26%; P =.01), mean (SD) duration of ventilation (6 [6] vs 10 [12] days; P =.01), mean (SD) length of ICU stay (9 [7] vs 15 [14] days; P =.02), and crude mortality (4% vs 26%; P =.002) were all lower among patients who received NIV than those treated with mechanical ventilation.

CONCLUSIONS

Use of NIV instead of mechanical ventilation is associated with a lower risk of nosocomial infections, less antibiotic use, shorter length of ICU stay, and lower mortality. JAMA. 2000;284:2361-2367.

Airway occlusion pressure to titrate positive end-expiratory pressure in patients with dynamic hyperinflation

BACKGROUND

Although the use of external positive end-expiratory pressure (PEEP) is recommended for patients with intrinsic PEEP, no simple method exists for bedside titration. We hypothesized that the occlusion pressure, measured from airway pressure during the phase of ventilator triggering (P0.1t), could help to indicate the effects of PEEP on the work of breathing (WOB).

METHODS

Twenty patients under assisted ventilation with chronic obstructive pulmonary disease were studied with 0, 5, and 10 cm H2O of PEEP while ventilated with a fixed level of pressure support.

RESULTS

PEEP 5 significantly reduced intrinsic PEEP (mean +/- SD, 5.2 +/- 2.4 cm H2O at PEEP 0 to 3.6 +/- 1.9 at PEEP 5; P < 0.001), WOB per min (12. 6 +/- 6.7 J/min to 9.1 +/- 5.9 J/min; P = 0.003), WOB per liter (1.2 +/- 0.4 J/l to 0.8 +/- 0.4 J/l; P < 0.001), pressure time product of the diaphragm (216 +/- 86 cm H2O. s-1. min-1 to 155 +/- 179 cm H2O. s-1. min-1; P = 0.001) and P0.1t (3.3 +/- 1.5 cm H2O to 2.3 +/- 1.4 cm H2O; P = 0.002). At PEEP 10, no further significant reduction in muscle effort nor in P0.1t (2.5 +/- 2.1 cm H2O) occurred, and transpulmonary pressure indicated an increase in end-expiratory lung volume. Significant correlations were found between WOB per min and P0.1t at the three levels of PEEP (P < 0.001), and between the changes in P0.1t versus the changes in WOB per min (P < 0.005), indicating that P0.1t and WOB changed in the same direction. A decrease in P0.1 with PEEP indicated a decrease in intrinsic PEEP with a specificity of 71% and a sensitivity of 88% and a decrease in WOB with a specificity of 86% and a sensitivity of 91%.

CONCLUSION

These results show that P0.1t may help to assess the effects of PEEP in patients with intrinsic PEEP.