Impact of recipient and donor pretransplantation body mass index on early postosperative complications after lung transplantation.

BACKGROUND: Prior studies have assessed the impact of the pretransplantation recipient body mass index (BMI) on patient outcomes after lung transplantation (LT), but they have not specifically addressed early postoperative complications. Moreover, the impact of donor BMI on these complications has not been evaluated. The first aim of this study was to assess complications during hospitalization in the ICU after LT according to donor and recipient pretransplantation BMI. METHODS: All the recipients who underwent LT at Bichat Claude Bernard Hospital, Paris, between January 2016 and August 2022 were included in this observational retrospective monocentric study. Postoperative complications were analyzed according to recipient and donor BMIs. Univariate and multivariate analyses were also performed. The 90-day and one-year survival rates were studied. P < 0.05 was considered to indicate statistical significance. The Paris-North Hospitals Institutional Review Board approved the study. RESULTS: A total of 304 recipients were analyzed. Being underweight was observed in 41 (13%) recipients, a normal weight in 130 (43%) recipients, and being overweight/obese in 133 (44%) recipients. ECMO support during surgery was significantly more common in the overweight/obese group (p = 0.021), as were respiratory complications (primary graft dysfunction (PGD) (p = 0.006), grade 3 PDG (p = 0.018), neuroblocking agent administration (p = 0.008), prone positioning (p = 0.007)), and KDIGO 3 acute kidney injury (p = 0.036). However, pretransplantation overweight/obese status was not an independent risk factor for 90-day mortality. An overweight or obese donor was associated with a decreased PaO2/FiO2 ratio before organ donation (p < 0.001), without affecting morbidity or mortality after LT. CONCLUSION: Pretransplantation overweight/obesity in recipients is strongly associated with respiratory and renal complications during hospitalization in the ICU after LT.

[Spontaneous pneumomediastinum]. / Pneumomédiastin spontané.

INTRODUCTION: Pneumomediastinum, which can be spontaneous or secondary, is defined by the presence of free air in the mediastinum as shown on a chest X-ray and/or chest CT, with or without subcutaneous emphysema. Secondary pneumomediastinum develops in various contexts (thoracic traumatism, perforation of central airway or digestive tract, pneumothorax, barotraumatism complicating mechanical ventilation…). Spontaneous pneumomediastinum , which will be the focus of this review, develops without any of the above-mentioned conditions. STATE OF ART: Spontaneous pneumomediastinum is a rare entity which usually occurs in young people either without medical history or with an history of asthma. A trigger event is detected in 40% to 60% of cases. Positive diagnosis is made on chest radiographt but thoracic CT is more sensitive. Distinction between spontaneous pneumomediastinum and secondary pneumomediastinum is in general easy but may sometimes be more difficult, particularly in case of oesophageal perforation. The evolution of spontaneous pneumomediastinum is most often benign but, rare complications may occur. Management is most often conservative. PERSPECTIVES: There is no consensual management of spontaneous pneumediastinum because of the lack of randomized prospective studies. This may be explained by the rarity of the disease. The actual trend is to offer to the patients a conservative treatment, which could be ambulatory in some cases. CONCLUSIONS: Spontaneous pneumomediastinum is a rare entity developing mainly in young subjects. The evolution is in general benign, justifying a conservative approach.

Acute Kidney Injury After Lung Transplantation: Perioperative Risk Factors and Outcome.

BACKGROUND: Acute kidney injury (AKI) is associated with increased short-term and long-term mortality and morbidity after lung transplantation (LT). The primary objective of this study was to analyze the perioperative factors associated with AKI according to Kidney Disease: Improving Global Outcome (KDIGO) criteria during hospitalization in an intensive care unit (ICU) after LT. METHODS: This was a single-center, observational, prospective study. AKI was defined according to KDIGO criteria. Results are expressed as median, interquartile range, absolute numbers, and percentages. Statistical analyses were performed using χ2 test, Fisher exact test, and Mann-Whitney U test. P < .05 was considered to be significant. Multivariate analysis was performed to identify independent risk factors. RESULTS: Between January 2016 and April 2018, 94 patients underwent LT (70% bilateral LT). AKI occurred during ICU stay in 46 patients (49%). KDIGO 1 AKI was observed in 16 patients (17%), KDIGO 2 in 14 patients (15%), and KDIGO 3 in 16 patients (17%), including 12 patients (75%) who required renal replacement therapy. AKI occurred before the fifth day after surgery for 38 patients (82% of the AKI patients). On multivariate analysis, independent factors associated with AKI were bilateral LT and mechanical ventilation >3 days (odds ratio [OR] 4.26, 95% confidence interval [CI] [1.49; 13.63] P = .010 and OR 5.56 [1.25; 11.47] P = .018, respectively). AKI and the need for renal replacement therapy were significantly associated with ICU mortality, 28-day mortality, and 1-year mortality. CONCLUSION: AKI is common during ICU stay after LT, especially after bilateral LT, and is associated with prolonged mechanical ventilation and increased short-term and long-term mortality.

Fungal Isolation in Respiratory Tract After Lung Transplantation: Epidemiology, Clinical Consequences, and Associated Factors.

BACKGROUND: Fungus-positive respiratory samples (FPRS) are common in the intensive Care unit (ICU) and are usually considered to correspond to colonization. The management of FPRS during the early postoperative course after lung transplantation (LT) remains unclear. The epidemiology, clinical consequences, and prognosis of FPRS were assessed in LT recipients. METHODS: Over a 6-year period, we analyzed the postoperative ICU course of 176 LT recipients with a specific focus on microbiological results of routine respiratory samples and clinical course. The outcomes during the ICU stay at day 28 and at 1 year were compared in patients with or without FPRS. Results are expressed as median and interquartile range. RESULTS: In the pretransplantation period, Candida spp were reported in 17% of patients. No routine post-LT antifungal prophylaxis was initiated. In the post-LT period, at least 1 FPRS was observed in 69% of patients (93% Candida spp, 7% Aspergillus spp). Double LT (odds ratio = 4.15, 95% confidence interval [1.67-11.80], P = .0007) was the only risk factor associated with Candida spp in respiratory samples. Antifungal therapy was administered in 58% of patients with post-LT Candida-positive samples. Candida spp in post-LT respiratory samples were not associated with increased ICU, 28-day, or 1-year mortality rates. CONCLUSION: A high prevalence of FPRS is reported after LT, mainly with Candida spp. The lack of association between post-LT FPRS and mortality and morbidity suggests avoiding antifungal therapy in the absence of clinical signs of invasive infection.

Impact of intensive care unit relocation and role of tap water on an outbreak of Pseudomonas aeruginosa expressing OprD-mediated resistance to imipenem.

BACKGROUND: To assess the impact of the incidental relocation of an intensive care unit (ICU) on the risk of colonizations/infections with Pseudomonas aeruginosa exhibiting OprD-mediated resistance to imipenem (PA-OprD). AIM: The primary aim was to compare the proportion of PA-OprD among P. aeruginosa samples before and after an incidental relocation of the ICU. The role of tap water as a route of contamination for colonization/infection of patients with PA-OprD was assessed as a secondary aim. METHODS: A single-centre, observational, before/after comparison study was conducted from October 2013 to October 2015. The ICU was relocated at the end of October 2014. All P. aeruginosa-positive samples isolated from patients hospitalized ≥48 h in the ICU were included. Tap water specimens were collected every three months in the ICU. PA-OprD strains isolated from patients and tap water were genotyped using pulse-field gel electrophoresis. FINDINGS: A total of 139 clinical specimens of P. aeruginosa and 19 tap water samples were analysed. The proportion of PA-OprD strains decreased significantly from 31% to 7.7% after the relocation of the ICU (P = 0.004). All PA-OprD clinical specimens had a distinct genotype. Surprisingly, tap water was colonized with a single PA-OprD strain during both periods, but this single clone has never been isolated from clinical specimens. CONCLUSION: Relocation of the ICU was associated with a marked decrease in P. aeruginosa strains resistant to imipenem. The polyclonal character of PA-OprD strains isolated from patients and the absence of tap-water-to-patient contamination highlight the complexity of the environmental impact on the endogenous colonization/infection with P. aeruginosa.

HDL and endothelial protection.

High-density lipoproteins (HDLs) represent a family of particles characterized by the presence of apolipoprotein A-I (apoA-I) and by their ability to transport cholesterol from peripheral tissues back to the liver. In addition to this function, HDLs display pleiotropic effects including antioxidant, anti-apoptotic, anti-inflammatory, anti-thrombotic or anti-proteolytic properties that account for their protective action on endothelial cells. Vasodilatation via production of nitric oxide is also a hallmark of HDL action on endothelial cells. Endothelial cells express receptors for apoA-I and HDLs that mediate intracellular signalling and potentially participate in the internalization of these particles. In this review, we will detail the different effects of HDLs on the endothelium in normal and pathological conditions with a particular focus on the potential use of HDL therapy to restore endothelial function and integrity.

[Brain tissue oxygen pressure, for what, for whom?]. / Pression tissulaire cérébrale en oxygène : pour quoi faire et pour qui ?

The main purpose of neurointensive care is to fight against cerebral ischaemia. Ischaemia is the cell energy failure following inadequacy between supply of glucose and oxygen and demand. Ischemia monitoring starts with a global approach, especially with cerebral perfusion pressure (CPP) determined by mean arterial pressure and intracranial pressure (ICP). However, global monitoring is insufficient to detect "regional" ischaemia, leading to development of local monitoring such as brain oxygen partial pressure (PtiO(2)). PtiO(2) is measured on a volume of a few mm(3) from a probe implanted in the cerebral tissue. The normal value is classically included between 25 and 35 mmHg and critical ischemic threshold is 10 mmHg. Understanding what exactly is PtiO(2) is still a matter of debate. PtiO(2) is more an indicator of oxygen diffusion depending of oxygen arterial pressure (PaO(2)) and local cerebral blood flow (CBF). Increase PaO(2) to treat PtiO(2) would hide information about local CBF. PtiO(2) is useful for the detection of low local CBF even when ICP is low as in hypocapnia-induced vasoconstriction. PtiO(2)-guided management could lead to a continuous optimization of arterial oxygen transport for an optimal cerebral tissue oxygenation. Finally, PtiO(2) has probably a global prognostic value because studies showed that hypoxic values for a long period of time lead to an unfavourable neurologic outcome. In conclusion, PtiO(2) provides additional information for regional monitoring of cerebral ischaemia and deserves more intensive use to better understand it and probably improve neurointensive care management.

[From bench to bedside: should we believe in the efficacy of stem cells in cerebral ischaemia?]. / Du laboratoire au lit du patient: faut-il croire à l'efficacité des "cellules souches" Dans l'ischemie cérébrale?

Stroke is the third cause of mortality and the leading cause of morbidity in industrialized countries. At the present time, ischaemic stroke is treated at the acute phase by thrombolysis with a recombinant of the tissular-plasminogen activator, which must be administered within the first 3 hours. Cell therapy, while using the self-renewal and differentiation potentials of stem cells, brings new hope for the long-term care of ischaemic stroke. Animal studies show that stem cells improve functional deficit without reduction of infarct volume and with very rare differentiation of the stem cell. These experimental studies suggest that stem cells would support cerebral plasticity via growth factor production and stimulation of endogenous mechanisms of local repair. Assessment of effectiveness and safety in the use of stem cells in cerebral ischaemia still require thorough investigation before clinical trials in humans can be developed.