Pneumopathies médicamenteuses en réanimation

The diagnosis of drug-induced lung disease (DILD) is a diagnosis of exclusion based on chronological and semiological criteria (intrinsic accountability) as well as bibliographic criteria (extrinsic accountability). In the intensive care unit, DILD incidence is difficult to assess because of the difficulty in obtaining a definitive diagnosis. In case of severe bilateral pneumonia and after ruling out the most common etiologies (infectious and cardiogenic pulmonary edema), DILD should be systematically suspected as involved in about 10% of acute respiratory distress syndromes (ARDS). Out of the 400 drugs known as “pneumotoxic” and mentioned on pneumotox.com website, about one hundred (including amiodarone, chemotherapy, and targeted therapies) has been described as able to result in ARDS.     

Probiotiques en réanimation

An acknowledgment of the crucial role of intestinal tract and digestive flora has aroused growing interest in the use of probiotics (defined as “live microorganisms that, when administered in adequate amount, confer a beneficial health effect”) during various intestinal disorders such as chronic inflammatory bowel disease, antibiotic-associated diarrhea, and extra-digestive diseases, namely atopic dermatitis, allergy, and asthma. However, clinical data related to their use in the intensive care unit, especially with the aim to prevent ventilator-associated pneumonia, are scarce and conflicting. We hereby review and discuss the usefulness of probiotics in critically ill patients.     

Candidoses en réanimation

Invasive candidiasis is a dread complication in hospitalized patients, characterized by mortality rates comparable to that of septic shock (40 to 60%). Its incidence in hospitalized patients is 0.5/1000 admissions, but about 10 per 1000 admissions in critical care where it represents 5 % to 10 % of all nosocomial bloodstream infections. Although a high proportion of hospitalized patients may become colonized with Candida spp, only a minority subsequently develop an infection. Clinical signs of such infection manifest only late rending them particularly difficult to diagnose. Early empiric antifungal treatment may improve the prognosis. However, for economical and epidemiological reasons, such a treatment can not be applied to all patients at risk. For these patients, empiric antifungal treatment could be started only when the colonization index reaches a threshold value that predicts subsequent infection. A better knowledge of the pathophysiology of Candida infections and the availability of triazoles compounds that are less toxic than amphotericin B, allowed the concept of prophylactic and preemptive therapy. However, antifungal prophylaxis is suspected as a major promoter of the emergence of potentially resistant non-albicans Candida, mostly in cancer centers. For critically ill patients, a strict restriction of prophylaxis to selected groups of patients for whom its efficacy is proven may contribute to limit this epidemiology.     

Complications infectieuses graves chez le transplanté rénal en réanimation

Kidney transplantation is the most frequent solid organ transplantation. Thanks to the advances in immunosuppressive therapy and the development of new immunosuppressive drugs, eligibility criteria of donors and recipients have expanded, incidence of acute rejection has decreased, and long-term graft survival has improved. However, despite a better management of antimicrobial prophylaxis, transplantation of patients with more comorbid conditions and use of more potent immunosuppressive regimens have led to an increase in the incidence of infectious complications. They represent the first reason for admission to the intensive care unit (ICU) among kidney transplant recipients. In 20–30% of cases, ICU admission is preceded by the treatment of an acute rejection. Moreover, the reactivation of cytomegalovirus, which could promote the occurrence of infections by its immunomodulatory properties, is found before or during ICU admission in 16–36% patients. Infected sites and pathogens depend on the time between transplantation and ICU admission, but especially on the severity of immune depression. Pneumonia, which is bacterial in two-third of cases, is the leading cause. Pneumocystis jirovecii is the most frequent opportunistic pathogen. Inhospital mortality range between 20 and 60%. Chronic allograft dysfunction is observed in 40% of survivors. Therefore, intensivists should be aware of epidemiology, risk factors, clinical presentation, and treatment of the main infectious complications following kidney transplantation.     

Hypophosphorémies en réanimation

Hypophosphatemia is commonly observed in acutely ill patients. Several clinical situations may induce it. The decrease in blood phosphate level may be due to an intracellular phosphorus shift and trapping or secondary to phosphate depletion. When observed in insulin-treated diabetic ketoacidosis or after sustained respiratory alkalosis, hypophosphatemia is usually not complicated and improves spontaneously. On the other hand, phosphate depletion may induce severe cardiac, respiratory and neuromuscular complications especially in alcoholic and long-starving patients, when refeeding uses a high carbohydrate diet or glucose infusion. Cytokine-induced hypophosphatemia may also occur in severe sepsis, septic shock and bacteremia. Although there is no general agreement in this field, phosphate supplementation is indicated in malnourished and alcoholic patients, during exclusive parenteral nutrition or whatever the clinical situation, when phosphate blood level has decreased below 10mg l^–1.     

Renutrition en réanimation pédiatrique

Denutrition is a frequent issue in the paediatric intensive care unit (ICU). Features are specific in relation to the child??s growth. Requirements of critically ill children cannot be adapted from energetic needs of adult or sane children. Recent studies demonstrated that caloric requirements of ICU children are lower than those in healthy children despite normal protein needs. Indirect calorimetry should help precise monitoring of caloric requirements in critically ill children to limit the risk of overfeeding syndrome. In the presence of functional digestive tract, enteral feeding should be preferred due to its better tolerance and less frequent infectious complications.     

Le transplanté rénal en réanimation

Renal transplantation is the best therapeutic approach for patients with end stage renal disease. However, immunosuppressive regimen increases incidence of infections. Occurrence of severe sepsis remains the main cause of admission in the intensive care unit (ICU) for renal transplant recipients. After a short update about the most frequently used immunosuppressive drugs, this review will focus on the relationships between sepsis and immunosuppression and will detail the specific characteristics of renal transplant recipients admitted to the ICU. Further, management of immunosuppression in these patients will be discussed.     

Légionelloses graves en réanimation

During the last 20 years, Legionella pneumophila has been recognized in most studies as a common cause of severe community- and hospital-acquired pneumonia. Surprisingly, very few studies have focused on Legionella pneumonia requiring admission to the Intensive Care Unit. According to series, the mortality rate of patients admitted in ICU with Legionella pneumonia ranges from 15 to 33 %. Delay in instituting appropriate therapy is probably a factor of poor prognosis. So empirical anti-legionella therapy should be included in the treatment of severe pneumonia requiring ICU admission. Since 1977, erythromycin has been the drug of choice for pneumonia due to L. pneumophila but fluoroquinolones and the new macrolides have superior in vitro activity and greater intracellular penetration. These experimental data strongly suggest that there may be a benefit to treat severe Legionella pneumonia with fluoroquinolones or new macrolides rather than with erythromycin. However, no controlled clinical trial has been performed in order to confirm these experimental data.     

Les pratiques transfusionnelles en réanimation

Blood transfusions are a common event in the ICU with about a third of all patients receiving a transfusion at some point during their ICU stay. The theoretical rationale behind blood transfusion is fairly clear-cut: by increasing the hemoglobin concentration, oxygen delivery to the tissues will be improved and organ function optimized. However, in reality the situation is more complex. While increasing red cell mass may indeed increase oxygen delivery, there may not be a corresponding increase in oxygen uptake and tissue oxygen availability. In fact, despite traditional transfusion triggers set in the region of a hemoglobin value of 10 g/dl or a hematocrit of 30%, there is evidence that the system can tolerate much lower levels of anemia with few or no adverse effects. Several studies have suggested an increase in mortality in transfused patients, however, while many patients may indeed tolerate a lower hemoglobin value than traditionally thought, anemia is not a benign feature and acutely anemic patients also have higher mortality rates. The ‘optimal’ hemoglobin is, thus, a balance between the benefits of maximum hemoglobin levels and the potential adverse effects of blood transfusion and high hematocrit. In this article we will discuss some of the epidemiological data surrounding this issue and how its implications for transfusion practice in the ICU.     

Les fibroses pulmonaires en réanimation

Introduction – Idiopathic pulmonary fibrosis and pulmonary fibroses associated with systemic diseases are the most frequent diffuse interstitial pulmonary diseases. These conditions usually evolve slowly but irrevocably towards terminal respiratory failure. Their clinical course can also be complicated by episodes of severe acute respiratory failure, whose cause is not always obvious. Admission to the intensive care unit for respiratory support can then be discussed.News and facts – Few data in the literature have described the diagnostic and therapeutic management of acute respiratory failure in patients with pulmonary fibrosis. Recent retrospective series shed some new light on this management, underlining its difficult nature. Mechanical ventilation generally leads to the patient's death, despite anti-infectious and immunosuppressive treatments.Perspectives and projects – The mortality rate of acute respiratory failure in patients with pulmonary fibrosis is very high. A non aggressive ventilatory strategy, such as proposed in the acute respiratory distress syndrome, could lead to a decrease in the ventilator-induced lesions that possibly occur in these fragile lungs. Only prospective studies, which would be difficult to set up, could evaluate the impact of such a ventilatory approach on mortality.     

Lipides et poumon en réanimation

Artificial nutrition is an inevitable component of ICU techniques, and usually comes with side effects. Among these, the effects of parenteral lipids on pulmonary function has been described in patients with abnormalities of the ventilation/perfusion ratio. Underlying mechanisms are well-known and involve, under the effect of lipidic infusion, a change in the production of two types of eicosanoids, either vasoconstrictive or vasodilatative for the pulmonary artery. Depending on the rate of the lipidic infusion flow, there will be a more important synthesis of one or the other eicosanoid. A slow flow, eg. 100 g of triglycerids within 10–12 hours, will not change the ventilation/perfusion ratio and will not have any influence on haematosis. TCM-based emulsions hardly interfere with ecosanoids and can be given in adult respiratory distress syndrome. No real benefit was shown compared to a slowly-given soya emulsion. A new aspect of lipidic emulsion is the ability of fish oils and borage oil to modulate pulmonary inflammation and bronchi reactivity. These characteristics are favorable for their use in mucoviscidosis and in patients at risk of, or experiencing, ARDS.