[Operating principles, physiological effects and practical issues of high-flow nasal oxygen therapy]. / Principes de fonctionnement, effets physiologiques et aspects pratiques de l'oxygénothérapie à haut débit.

First-line symptomatic treatment of acute respiratory failure (ARF) usually requires standard oxygen therapy, of which the limits have nonetheless led to the development of heated and humidified high-flow nasal oxygen therapy (HFNO). HFNO enables the delivery, through simple nasal cannula, of up to 100% of well-heated and humidified fraction of inspired oxygen (FiO2), at a maximum flow rate of 50 to 70 L/min of gas according to the devices chosen (specific or ventilator). The technical characteristics and operating principles of HFNO (coverage of the patient's spontaneous inspiratory flow, improved conditioning of the inspired gases, comfortable nasal cannula) yield a number of interdependent physiological effects that improve not only oxygenation conditions but also ventilatory mechanics. While it could be indicated in many clinical situations, including first-line hypoxemic ARF, the simplicity of HFNO implementation and the respiratory comfort it procures should in no way minimize the clinical monitoring of patients for whom endotracheal intubation may be required, and should not be unduly delayed.

Changes in severity and organ failure scores as prognostic factors in onco-hematological malignancy patients admitted to the ICU.

OBJECTIVE: To determine whether severity and organ failure scores over the first 3 days in an ICU predict in-hospital mortality in onco-hematological malignancy patients. DESIGN AND SETTING: Retrospective study in a 22-bed medical ICU. PATIENTS: 92 consecutive patients with onco-hematological malignancies including 20 hematopoietic stem cell transplantation (HSCT) patients (11 with allogenic HSCT). MEASUREMENTS: Simplified Acute Physiology Score (SAPS) II, Organ Dysfunction and/or Infection (ODIN) score, Logistic Organ Dysfunction System (LODS), and Sequential Organ Failure Assessment (SOFA) score were recorded on admission. The change in each score (Delta score) during the first 3 days in the ICU was calculated as follows: severity or organ failure score on day 3 minus severity or organ failure score on day 1, divided by severity or organ failure score on day 1. RESULTS: In-hospital mortality was 58%. Using multivariate analysis in-hospital mortality was predicted by all scores on day 1 and all Delta scores. Areas under the receiver operating characteristics curves were similar for SAPS II (0.78), ODIN (0.78), LODS (0.83), and SOFA (0.78) scores at day 1. They were also similar for DeltaSAPS II, DeltaODIN, DeltaLODS, and DeltaSOFA. Similar results were observed when excluding patients with allogenic HSCT. CONCLUSION: Severity and three organ failure scores on day 1 and Delta scores perform similarly in predicting in-hospital mortality in ICU onco-hematological malignancy patients but do not predict individual outcome. Decision to admit such patients to the ICU or to forgo life-sustaining therapies should not be based on these scores.

Serum erythropoietin levels in septic shock.

Erythropoietin is a glycoprotein hormone mainly released by the kidney, which stimulates red blood cell production. However, in sepsis, the mechanisms responsible for the final increase in circulating erythropoietin remain unclear Seventeen critically ill patients with Simplified Acute Physiologic Score average 66 (range 43 to 103) were included in this study. Ten patients survived and seven died within 28 days. Blood samples obtained at different times were assayed for erythropoietin, cytokine levels and lactate measurements. PCO2 gap was assessed to detect the presence of gastric mucosal acidosis. Erythropoietin decreased in the patients who survived while it remained high or increased in non-survivors (37+/-6.5 vs 147+/-6. 7 UI/l respectively, P<0.05). Erythropoietin plasma levels were correlated with IL-6 levels (r=0.84, P<0.05) and TNFalpha levels (r=0.84, P<0.05). We observed a significant positive relationship between erythropoietin plasma levels and lactate concentrations (r= 0.89, P< 0. 05) and with PCO2 gap (r=0.9, P < 0.05). No correlation was found between erythropoietin concentration and the other parameters. High serum erythropoietin levels in non-survivors were observed with septic shock despite an increase in the levels of proinflammatory cytokines. We found a relationship between erythropoietin concentration and biological markers of tissue hypoperfusion i.e. lactate levels or PCO2 gap. This relationship could suggest tissue hypoperfusion as the stimulating factor for erythropoietin production in septic shock.

A shock associated with adult-onset Still's disease.

Only two cases of adult-onset Still's disease associated with shock have been previously described. We report a case of shock in a man with adult-onset Still's disease and discuss the relationship between the two processes by assessing tumor necrosis factor-alpha, procalcitonin and interleukin-6 concentrations.

Suppression of heparinization of central venous catheters between cycles of chemotherapy. Results of a phase I study.

A phase I study to evaluate heparinization of tunnelled subclavian catheters (TSC) was conducted in 42 patients who each had a TSC for chemotherapy. They were enrolled in the study from August 1994 to December 1995. The inclusion criteria were: age 18-70, no general anticoagulant treatment, TSC used only for chemotherapy, informed consent. Heparinization was performed at the end of each cycle and then at increasing intervals: 11, 13, 15, 17, 19, and 21 days. A 21-day interval was intended to mimic the suppression of heparinization between cycles. Heparinization was performed with a 250 IU/ml heparin solution. Anti-Xa activity was studied before each heparinization. For each interval, at least 5 patients were followed up for two cycles. If no blockages were present progression to the next step was authorized. If one blockage was observed 5 additional patients were required to have their TSCs heparinized after the same interval. Two blockages (block) after the same interval meant that the previous interval was recorded as the longest tolerable. There were no blocks with the 11-day interval (6 patients), 1 block after 13 days (10 patients), 1 block after 15 days (10 patients), and no blocks after 17 days (5 patients), 19 days (6 patients), or 21 days (5 patients). The median anti-Xa activity (curative rate 0.2-0.6) was, respectively 11 days 6.74; 13 days 5.47; 15 days 4.71; 17 days 3.61; 19 days 3.67; 21 days 5.10 (NS). Heparinization between two cycles of chemotherapy is unnecessary. A high level of heparin activity persisted constantly inside the catheter lumen through the 3-week observation period.

Long-term efficiency of home nasal mask ventilation in patients with diffuse bronchiectasis and severe chronic respiratory failure: a case-control study.

The aim of this study was to evaluate long-term efficacy and tolerance of nasal mask ventilation (NMV) in a comparative case-control study. Fourteen patients with diffuse bronchiectasis and severe chronic respiratory failure (CRF), treated by long-term oxygen-therapy (LTO) and NMV, were case matched with 14 patients with diffuse bronchiectasis and severe CRF treated with only LTO. Patients and control subjects were compared based on the following parameters: blood gases, FEV1, vital capacity, hospitalizations, and survival. Symptoms, Karnofsky function score, and clinical evolution were also monitored in patients. Three subgroups may be identified according to outcome: two early deaths (subgroup 1), six patients with initial improvement and subsequent deterioration (subgroup 2), and six patients whose conditions remained improved for >2 years (subgroup 3). PaO2 decrease slope was slighter in this last subgroup than subgroup 2. The days of hospitalization were significantly reduced after institution of NMV in the patient group. Comparison between patients and control subjects did not show any difference on PaO2 evolution and on the overall median survival (46 and 40 months in NMV and control group, respectively). Long-term tolerance and compliance remained satisfactory for 11 patients. These results suggest that NMV is feasible as a long-term home treatment in patients with diffuse bronchiectasis. Although our results may have failed to prove a long-term efficiency on the course of blood gases and survival, a beneficial effect is observed with reduction of hospitalizations and improvement of functional status. This study warrants further investigation, in a prospective series, with a larger number of patients.

[Long-term oxygen therapy at home. Compliance with the medical prescription and observance of the daily duration of at least 15 hours]. / Oxygénothérapie au long cours à domicile. Respect de la prescription médicale et observance d'une durée quotidienne d'au moins 15 heures.

Long-term domiciliary oxygen therapy in patients with chronic respiratory failure significantly improves both survival and quality of life. These therapeutic objetives are only achieved by daily oxygen therapy of more than 15 hours. For a period of 3 months, we have prospectively measured the duration of oxygen therapy in 930 patients with chronic airflow obstruction. This is carried out by reading the meters on the oxygen concentrators, or for liquid oxygen by checking the weight of the cylinders at each delivery, making allowances for the flow rate and also for natural loss from evaporation. The instructions for oxygen therapy and the true therapy of the patient were then gathered using a questionnaire. The practitioners were questioned on the prescription for oxygen therapy which had been made for each patient, and more generally on their usual criteria for prescribing long-term oxygen therapy. The patients (82% male) were aged between 67 +/- 8 years, and were on domiciliary oxygen therapy 36 +/- 24 months, with hypoxaemia (PaO2 = 56 +/- 9 mmHg), hypercapnea (PaCO = 47 +/- 8 mmHG) and suffering from airflow obstruction (FEV1/VC = 42 +/- 14%). The duration of prescribed oxygen therapy was on average 16 +/- 3 hours. The mean duration of oxygen therapy achieved was 14.5 +/- 5 hours, but only 45% of the patients (419/930) managed daily oxygen therapy superior of equal to 15 hours and were categorised as compliant.(ABSTRACT TRUNCATED AT 250 WORDS)

[Mediastinal bronchogenic cyst associated with a multiple malformation syndrome]. / Kyste bronchogénique médiastinal révélateur d'un syndrome polymalformatif.

The authors report a case of a patient presenting with a bronchogenic mediastinal cyst, which presented as a super-infection of the cyst. The cyst was associated with malformation of the cervical vertebra, cardiovascular abnormalities and congenital deafness, placing this in the group of rare complex polymalformation syndrome with Klippel-Feil Syndrome. The authors also stress the value of computed tomography, and above all of nuclear magnetic resonance in the analysis of mediastinal tumours and in particular, of bronchogenic cysts.

[A benign broncho-pulmonary lesion may hide another. Association of a granular cell tumor and an intrapulmonary lymphatic ganglion]. / Une lésion bénigne broncho-pulmonaire peut en cacher une autre. Association d'une tumeur à cellules granuleuses et d'un ganglion lymphatique intrapulmonaire.

The authors record the case of a patient who was under review for pulmonary tuberculosis in whom an Abrikossof granular cell tumour and a cyst were found which had developed from an intrapulmonary lymph node. These two entities are rare and their association extremely unusual and have never been described until now. We review their histogenesis.