The future of intensive care: the study of the microcirculation will help to guide our therapies.

The goal of hemodynamic resuscitation is to optimize the microcirculation of organs to meet their oxygen and metabolic needs. Clinicians are currently blind to what is happening in the microcirculation of organs, which prevents them from achieving an additional degree of individualization of the hemodynamic resuscitation at tissue level. Indeed, clinicians never know whether optimization of the microcirculation and tissue oxygenation is actually achieved after macrovascular hemodynamic optimization. The challenge for the future is to have noninvasive, easy-to-use equipment that allows reliable assessment and immediate quantitative analysis of the microcirculation at the bedside. There are different methods for assessing the microcirculation at the bedside; all have strengths and challenges. The use of automated analysis and the future possibility of introducing artificial intelligence into analysis software could eliminate observer bias and provide guidance on microvascular-targeted treatment options. In addition, to gain caregiver confidence and support for the need to monitor the microcirculation, it is necessary to demonstrate that incorporating microcirculation analysis into the reasoning guiding hemodynamic resuscitation prevents organ dysfunction and improves the outcome of critically ill patients.

Impact of platelet transfusion on outcomes in trauma patients.

BACKGROUND: Trauma-induced coagulopathy includes thrombocytopenia and platelet dysfunction that impact patient outcome. Nevertheless, the role of platelet transfusion remains poorly defined. The aim of the study was 1/ to evaluate the impact of early platelet transfusion on 24-h all-cause mortality and 2/ to describe platelet count at admission (PCA) and its relationship with trauma severity and outcome. METHODS: Observational study carried out on a multicentre prospective trauma registry. All adult trauma patients directly admitted in participating trauma centres between May 2011 and June 2019 were included. Severe haemorrhage was defined as ≥ 4 red blood cell units within 6 h and/or death from exsanguination. The impact of PCA and early platelet transfusion (i.e. within the first 6 h) on 24-h all-cause mortality was assessed using uni- and multivariate logistic regression. RESULTS: Among the 19,596 included patients, PCA (229 G/L [189,271]) was associated with coagulopathy, traumatic burden, shock and bleeding severity. In a logistic regression model, 24-h all-cause mortality increased by 37% for every 50 G/L decrease in platelet count (OR 0.63 95% CI 0.57-0.70; p < 0.001). Regarding patients with severe hemorrhage, platelets were transfused early for 36% of patients. Early platelet transfusion was associated with a decrease in 24-h all-cause mortality (versus no or late platelets): OR 0.52 (95% CI 0.34-0.79; p < 0.05). CONCLUSIONS: PCA, although mainly in normal range, was associated with trauma severity and coagulopathy and was predictive of bleeding intensity and outcome. Early platelet transfusion within 6 h was associated with a decrease in mortality in patients with severe hemorrhage. Future studies are needed to determine which doses of platelet transfusion will improve outcomes after major trauma.

French recommendations for the management of patients with spinal cord injury or at risk of spinal cord injury.

OBJECTIVES: To update the French guidelines on the management of trauma patients with spinal cord injury or suspected spinal cord injury. DESIGN: A consensus committee of 27 experts was formed. A formal conflict-of-interest (COI) policy was developed at the outset of the process and enforced throughout. The entire guidelines process was conducted independently of any industrial funding (i.e. pharmaceutical, medical devices). The authors were advised to follow the rules of the Grading of Recommendations Assessment, Development and Evaluation (GRADE®) system to guide assessment of quality of evidence. The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasised. METHODS: The committee studied twelve questions: (1) What are the indications and arrangements for spinal immobilisation? (2) What are the arrangements for pre-hospital orotracheal intubation? (3) What are the objectives of haemodynamic resuscitation during the lesion assessment, and during the first few days in hospital? (4) What is the best way to manage these patients to improve their long-term prognosis? (5) What is the place of corticosteroid therapy in the initial phase? (6) What are the indications for magnetic resonance imaging in the lesion assessment phase? (7) What is the optimal time for surgical management? (8) What are the best arrangements for orotracheal intubation in the hospital environment? (9) What are the specific conditions for weaning these patients from mechanical ventilation for? (10) What are the procedures for analgesic treatment of these patients? (11) What are the specific arrangements for installing and mobilising these patients? (12) What is the place of early intermittent bladder sampling in these patients? Each question was formulated in a PICO (Patients, Intervention, Comparison, Outcome) format and the evidence profiles were produced. The literature review and recommendations were made according to the GRADE® Methodology. RESULTS: The experts' work synthesis and the application of the GRADE method resulted in 19 recommendations. Among the recommendations formalised, 2 have a high level of evidence (GRADE 1+/-) and 12 have a low level of evidence (GRADE 2+/-). For 5 recommendations, the GRADE method could not be applied, resulting in expert advice. After two rounds of scoring and one amendment, strong agreement was reached on all the recommendations. CONCLUSIONS: There was significant agreement among experts on strong recommendations to improve practices for the management of patients with spinal cord injury.

Correction to: Serum sodium and intracranial pressure changes after desmopressin therapy in severe traumatic brain injury patients: a multi-centre cohort study.

Following publication of the original article [1], we were notified that the collaborators' names part of the "The TBI Collaborative" group has not been indexed in Pubmed. Below the collaborators names full list.

Serum sodium and intracranial pressure changes after desmopressin therapy in severe traumatic brain injury patients: a multi-centre cohort study.

BACKGROUND: In traumatic brain injury (TBI) patients desmopressin administration may induce rapid decreases in serum sodium and increase intracranial pressure (ICP). AIM: In an international multi-centre study, we aimed to report changes in serum sodium and ICP after desmopressin administration in TBI patients. METHODS: We obtained data from 14 neurotrauma ICUs in Europe, Australia and UK for severe TBI patients (GCS ≤ 8) requiring ICP monitoring. We identified patients who received any desmopressin and recorded daily dose, 6-hourly serum sodium, and 6-hourly ICP. RESULTS: We studied 262 severe TBI patients. Of these, 39 patients (14.9%) received desmopressin. Median length of treatment with desmopressin was 1 [1-3] day and daily intravenous dose varied between centres from 0.125 to 10 mcg. The median hourly rate of decrease in serum sodium was low (- 0.1 [- 0.2 to 0.0] mmol/L/h) with a median period of decrease of 36 h. The proportion of 6-h periods in which the rate of natremia correction exceeded 0.5 mmol/L/h or 1 mmol/L/h was low, at 8% and 3%, respectively, and ICPs remained stable. After adjusting for IMPACT score and injury severity score, desmopressin administration was independently associated with increased 60-day mortality [HR of 1.83 (1.05-3.24) (p = 0.03)]. CONCLUSIONS: In severe TBI, desmopressin administration, potentially representing instances of diabetes insipidus is common and is independently associated with increased mortality. Desmopressin doses vary markedly among ICUs; however, the associated decrease in natremia rarely exceeds recommended rates and median ICP values remain unchanged. These findings support the notion that desmopressin therapy is safe.

How useful are hemoglobin concentration and its variations to predict significant hemorrhage in the early phase of trauma? A multicentric cohort study.

BACKGROUND: The diagnostic value of hemoglobin (Hb) for detecting a significant hemorrhage (SH) in the early phase of trauma remains controversial. The present study aimed to assess the abilities of Hb measurements taken at different times throughout trauma management to identify patients with SH. METHODS: All consecutive adult trauma patients directly admitted to six French level-1 trauma centers with at least one prehospital Hb measurement were analyzed. The abilities of the following variables to identify SH (≥ 4 units of red blood cells in the first 6 h and/or death related to uncontrolled bleeding within 24 h) were determined and compared to that of shock index (SI): Hb as measured with a point-of-care (POC) device by the prehospital team on scene (POC-Hbprehosp) and upon patient's admission to the hospital (POC-Hbhosp), the difference between POC-Hbhosp and POC-Hbprehosp (DeltaPOC-Hb) and Hb as measured by the hospital laboratory on admission (Hb-Labhosp). RESULTS: A total of 6402 patients were included, 755 with SH and 5647 controls (CL). POC-Hbprehosp significantly predicted SH with an area under ROC curve (AUC) of 0.72 and best cutoff values of 12 g/dl for women and 13 g/dl for men. POC-Hbprehosp < 12 g/dl had 90% specificity to predict of SH. POC-Hbhosp and Hb-Labhosp (AUCs of 0.92 and 0.89, respectively) predicted SH better than SI (AUC = 0.77, p < 0.001); best cutoff values of POC-Hbhosp were 10 g/dl for women and 12 g/dl for men. DeltaPOC-Hb also predicted SH with an AUC of 0.77, a best cutoff value of - 2 g/dl irrespective of the gender. For a same prehospital fluid volume infused, DeltaPOC-Hb was significantly larger in patients with significant hemorrhage than in controls. CONCLUSIONS: Challenging the classical idea that early Hb measurement is not meaningful in predicting SH, POC-Hbprehosp was able, albeit modestly, to predict significant hemorrhage. POC-Hbhosp had a greater ability to predict SH when compared to shock index. For a given prehospital fluid volume infused, the magnitude of the Hb drop was significantly higher in patients with significant hemorrhage than in controls.

Femoral arterial and central venous catheters in the trauma resuscitation room.

BACKGROUND: Arterial and central venous femoral catheters (fAC-CVC) use during the initial management of severe trauma patients is not a standard technique in most trauma centers. Arguments in favor of their use are: continuous monitoring of blood pressure, safe drug administration, easy blood sampling and potentially large bore venous access. The lack of evidence makes the practice heterogeneous. The aim of the present study was to describe the use and complications of fAC-CVC in the trauma bay in two centers where they are routinely used. METHODS: This was a retrospective analysis of routine fAC-CVC use from two French trauma centers. All patients admitted directly to the trauma resuscitation room were included. Demographic, clinical and biological data were collected from the scene to discharge to describe the use of catheters during initial trauma management including infectious, mechanical and thrombotic complications. RESULTS: 243 pairs of femoral catheters were inserted among 692 patients admitted in both trauma centers. Femoral AC-CVC use was more frequent in critically ill patients with higher ISS 26 [17; 41] vs 13 [8; 24], p < 0.001(median [quartile 1-3]), severe traumatic brain injury (AIS head 1[0-4] vs 0[0-3], p < 0.001), lower systolic blood pressure, 92 (37) vs 113 (28) mmHg, p < 0.001 mean (standard deviation), lower haemoglobin on arrival, 10.9 (3) vs 13.3 (2.1) g/dL (p < 0.001), and higher blood lactate concentration, 4.0 (3.9) vs 2.1 (1.8) mmol/L (p < 0.001). In patients with fAC-CVC use time in the trauma room was longer, 46 [40;60] vs 30 [20;40] minutes (p < 0.05). In total 52 colonizations and 3 bloodstream infections were noted in 1000 catheter days. An incidence of 12% of mechanical complications and of 42% deep venous thromboses were observed. Of the latter none was associated with confirmed pulmonary embolism. CONCLUSION: Femoral AC-CVC appeared to be deployed more often in critically ill patients, presenting with shock and/or traumatic brain injury in particular. The observed rate of complications in this sample seems to be low compared to reported rates.

High level of venous thromboembolism in critically ill trauma patients despite early and well-driven thromboprophylaxis protocol.

BACKGROUND: Venous thromboembolism (VTE) is one of the most common preventable causes of in-hospital death in trauma patients surviving their injuries. We assessed the prevalence, incidence and risk factors for deep venous thrombosis (DVT) and pulmonary embolism (PE) in critically ill trauma patients, in the setting of a mature and early mechanical and pharmacological thromboprophylaxis protocol. METHODS: This was a prospective observational study on a cohort of patients from a surgical intensive care unit of a university level 1 trauma centre. We enrolled consecutive primary trauma patients expected to be in intensive care for ≥48 h. Thromboprophylaxis was protocol driven. DVT screening was performed by duplex ultrasound of upper and lower extremities within the first 48 h, between 5 and 7 days and then weekly until discharge. We recorded VTE risk factors at baseline and on each examination day. Independent risk factors were analysed using a multivariate logistic regression. RESULTS: In 153 patients with a mean Injury Severity Score of 23 ± 12, the prevalence of VTE was 30.7%, 95 CI [23.7-38.8] (29.4% DVT and 4.6% PE). The incidence was 18%, 95 CI [14-24] patients-week. The median time of apparition of DVT was 6 days [1; 4]. The global protocol compliance was 77.8% with a median time of introduction of the pharmacological prophylaxis of 1 day [1; 2]. We identified four independent risk factors for VTE: central venous catheter (OR 4.39, 95 CI [1.1-29]), medullar injury (OR 5.59, 95 CI [1.7-12.9]), initial systolic arterial pressure <80 mmHg (OR 3.64, 95 CI [1.3-10.8]), and pelvic fracture (OR 3.04, 95 CI [1.2-7.9]). CONCLUSION: Despite a rigorous, protocol-driven thromboprophylaxis, critically ill trauma patients showed a high incidence of VTE. Further research is needed to tailor pharmacological prophylaxis and balance the risks and benefits.

Early Recruitment of Cerebral Microcirculation by Neuronal Nitric Oxide Synthase Inhibition in a Juvenile Ischemic Rat Model.

BACKGROUND: The development of collateral circulation is proposed as an inherent compensatory mechanism to restore impaired blood perfusion after ischemia, at least in the penumbra. We have studied the dynamic macro- and microcirculation after ischemia-reperfusion in the juvenile rat brain and evaluated the impact of neuronal nitric oxide synthase (nNOS) inhibition on the collateral flow. METHODS: Fourteen-day-old (P14) rats were subjected to ischemia-reperfusion and treated with either PBS or 7-nitroindazole (7-NI, an nNOS inhibitor, 25 mg/kg). Arterial blood flow (BF) was measured using 2D-color-coded pulsed ultrasound imaging. Laser speckle contrast (LSC) imaging and sidestream dark-field videomicroscopy were used to measure cortical and microvascular BF, respectively. RESULTS: In basal conditions, 7-NI reduced BF in the internal carotids (by ∼ 25%) and cortical (by ∼ 30%) BF, as compared to PBS. During ischemia, the increased mean BF velocity in the basilar trunk after both PBS and 7-NI demonstrated the establishment of collateral support and patency. Upon re-flow, BF immediately recovered to basal values in the internal carotid arteries under both conditions. The 7-NI group showed increased collateral flow in the penumbral tissue during early re-flow compared to PBS, as shown with both LSC imaging and side-stream dark-field videomicroscopy. The proportion of perfused capillaries was significantly increased under 7-NI as compared to PBS when given before ischemia (67.0 ± 3.9 vs. 46.8 ± 8.8, p < 0.01). Perfused capillaries (63.1 ± 17.7 vs. 81.1 ± 20.7, p < 0.001) and the BF index (2.4 ± 0.6 vs. 1.3 ± 0.1, p < 0.001) significantly increased under 7-NI given at the re-flow onset. CONCLUSIONS: Collateral support in the penumbra is initiated during ischemia, and may be increased during early re-flow by neuronal NOS inhibition (given in pre- and post-treatment), which may preserve brain tissue in juvenile rats.

[The initial management in intensive care of pelvic ring injury patients]. / Prise en charge initiale en réanimation des traumatisés graves du bassin.

Pelvic trauma care is complex since it is frequently associated with multiple injuries and may lead to dramatic and uncontrollable haemorrhage. After pelvic trauma, the mortality, around 8 to 10%, is mainly related to severe pelvic hemorrhage but also to extrapelvic injuries (thoracic, abdominal or brain injuries). It is therefore crucial to manage pelvic trauma in specialized trauma center. The initial trauma assessment aims to determine the role of the pelvic injury in hemorrhage to define the therapeutic strategy of pelvic trauma care (arterial embolisation/pelvic ring stabilisation). This review was performed with a systematic review of the literature; it describes the pelvic fracture pathophysiology, and the efficacy and safety of haemostatic procedures and with their respective indications. A decision making algorithm is proposed for the treatment of trauma patients with pelvic fracture.

Resistive Index or color-Doppler semi-quantitative evaluation of renal perfusion by inexperienced physicians: results of a pilot study.

BACKGROUND: Doppler-based renal resistive index (RI) calculation may help in the early detection of acute kidney injury (AKI). Its feasibility and reproducibility by inexperienced operators remain unknown. The main objective of this study was to compare performances of junior and senior operators in assessing renal perfusion using both the semiquantitative color-Doppler scale and RI calculation. METHODS: Prospective cohort study performed in 3 ICUs. Inexperienced juniors physicians attended a half-day course on renal perfusion assessment using RI calculation and color-Doppler (from 0, absence of renal perfusion; to 3, renal vessels identifiable in the entire field of view). Junior and senior operators used both methods in 69 mechanically ventilated patients, in blind fashion. RESULTS: Failure to obtain RI occurred for a junior operator in a single patient. RI and color-Doppler semi-quantitative values obtained by operators were correlated (r²=0.64 and r²=0.61, respectively). Systematic bias across operators as assessed using Bland-Altman plots was negligible (-0.001 and -0.29, respectively), although precision was limited (95% confidence intervals, +0.105 to -0.107 and +0.98 to -1.04, respectively). RI calculation and semi-quantitative assessment performed well for diagnosing persistent AKI (area under the receiver-operating characteristic curve, 0.84 [95% confidence interval, 0.73-0.97] and 0.87 [0.77-0.97], respectively). CONCLUSION: A brief course on renal Doppler allowed inexperienced operators to assess effectively renal perfusion with a good reliability when compared to senior operators. In addition, our results suggest the good diagnostic performance of both Doppler-based RI and semi-quantitative renal perfusion assessment in predicting short-term renal dysfunction reversibility.

[Organization of mechanical ventilation in French Intensive care units]. / Organisation de la ventilation artificielle dans les unités de réanimation en France.

OBJECTIVES: To clarify the procedures related to mechanical ventilation in the intensive care unit setting: allocation of ventilators, team education, maintenance and reference documents. STUDY DESIGN: Declarative survey. METHODS: Between September and December 2010, we assessed the assignment and types of ventilators (ICU ventilators, temporary repair ventilators, non-invasive ventilators [NIV], and transportation ventilators), medical and nurse education, maintenance of the ventilators, presence of reference documents. Results are expressed in median/range and proportions. RESULTS: Among the 62 participating ICUs, a median of 15 ventilators/ICU (range 1-50) was reported with more than one trademark in 47 (76%) units. Specific ventilators were used for NIV in 22 (35%) units, temporary repair in 49 (79%) and transportation in all the units. Nurse education courses were given by ICU physicians in 54 (87%) units or by a company in 29 (47%) units. Medical education courses were made by ICU senior physicians in 55 (89%) units or by a company in 21 (34%) units. These courses were organized occasionally in 24 (39%) ICU and bi-annually in 16 (26%) units. Maintenance procedures were made by the ICU staff in 39 (63%) units, dedicated staff (17 [27%]) or bioengineering technicians (14 [23%] ICU). Reference documents were written for maintenance procedures in 48 (77%) units, ventilator setup in 22 (35%) units and ventilator dysfunction in 20 (32%) ICU. CONCLUSIONS: This first survey shows disparate distribution of ventilators and practices among French ICU. Education and understanding of the proper use of ventilators are key issues for security improvement.

The initial management of trauma patients is an especially relevant setting to evaluate professional practice patterns.

The initial management of trauma patients in a dedicated location is a crucial step in the treatment of these patients. The characteristics of this phase are such that they meet all the criteria for a professional practice patterns evaluation (PPPE or PPE): formalized protocols, clear-cut timeframes, specific roles of different stakeholders, and multidisciplinary medical and paramedical team. In addition, the expected result of the PPE approach, improved care, will have a direct impact on patient outcomes. This PPE modeled on an audit aims at evaluating the care process based on representative criteria. These criteria should include: the planned structure and organization; the protocols; the strategy and time frames for procedure implementation; the relationships between stakeholders; the results. For each criterion, differences between the expected characteristics and the observed reality are analyzed. The prospective (independent observer or video) and/or retrospective (records, register) collection of data during 20 consecutive encounters should be sufficient to identify dysfunctions and provide guidance on the changes that need to be implemented. The proposed data collection form includes 15 items representative of the five defined criteria. These items often describe departmental choice. The pursuit of quality is defined first in terms of medical and paramedical results, but also in administrative and financial terms. Following the analysis produced by a representative group of actors, a multidisciplinary discussion of the results should be followed by proposals for simple changes approved by everyone. After a few months of implementation, the impact of the proposed improvement measures will be assessed by a new survey. This approach, in addition to improving the quality of care, allows better team stress management and greater work enjoyment.

The initial management of severe trauma patients at hospital admission.

The initial management of trauma patient is a critical period aiming at: stabilizing the vital functions; following a rigorous injury assessment; defining a therapeutic strategy. This management has to be organized to minimize loss of time that would be deleterious for the patients outcome. Thus, before patient arrival, the trauma team alert should lead to the initiation of care procedures adapted to the announced severity of the patient. Moreover, each individual should know its role in advance and the team should be managed by only one individual (the trauma leader) to avoid conflicts of decision. A rapid trauma injury assessment aims not only at guiding resuscitation (chest drainage, pelvic contention, to define the mean arterial pressure goal) but also to decide a critical intervention in case of hemodynamic instability (laparotomy, thoracotomy, arterial embolisation). This initial assessment includes a chest and a pelvic X-ray, abdominal ultrasound (extended to the lung) and transcranial Doppler (TCD). The whole body scanner with administration of intravenous contrast material is the cornerstone of the injury assessment but can be done for patients stabilized after the initial resuscitation.

Endotoxin-induced basal respiration alterations of renal HK-2 cells: a sign of pathologic metabolism down-regulation.

To study the mechanism of oxygen regulation in inflammation-induced acute kidney injury, we investigate the effects of a bacterial endotoxin (lipopolysaccharide, LPS) on the basal respiration of proximal tubular epithelial cells (HK-2) both by high-resolution respirometry and electron spin resonance spectroscopy. These two complementary methods have shown that HK-2 cells exhibit a decreased oxygen consumption rate when treated with LPS. Surprisingly, this cellular respiration alteration persists even after the stress factor was removed. We suggested that this irreversible decrease in renal oxygen consumption after LPS challenge is related to a pathologic metabolic down-regulation such as a lack of oxygen utilization by cells.

Identification of the naturally occurring genes encoding carbapenem-hydrolysing oxacillinases from Acinetobacter haemolyticus, Acinetobacter johnsonii, and Acinetobacter calcoaceticus.

Carbapenem resistance is increasingly being reported among Acinetobacter species, and results mostly from the expression of acquired carbapenem-hydrolysing oxacillinases (CHDLs). Several Acinetobacter species intrinsically possess chromosomal CHDL genes: Acinetobacter baumannii (bla(OXA-51) ), Acinetobacter radioresistens (bla(OXA-23) ), and Acinetobacter lwoffii (bla(OXA-134) ). We aimed to identify the progenitors of novel CHDL-encoding genes for identification of potential reservoirs. We performed PCR screening using degenerated internal primers designed from a sequence alignment of the known CHDLs (OXA-23, OXA-40, OXA-51, OXA-58, OXA-134, and OXA-143) applied to a collection of 50 Acinetobacter strains belonging to 23 different species. Two strains of Acinetobacter johnsonii, one strain of Acinetobacter calcoaceticus and two strains of Acinetobacter haemolyticus were found to harbour, respectively, the totally novel bla(OXA-211) -like, bla(OXA-213) -like and bla(OXA-214) -like genes. In addition, the complete genomes of those three species available in GenBank, i.e. one A. johnsonii genome, four A. calcoaceticus genomes, and one A. haemolyticus genome, were analysed and found to be positive for the presence of bla(OXA211) -like, bla(OXA-213) -like and bla(OXA-214) -like genes, respectively. The ß-lactamases OXA-211, OXA-213 and OXA-214 are diverse, with amino acid identities ranging from 53% to 76%, as compared with the naturally occurring OXA-51-like CHDL from A. baumannii. These ß-lactamases showed a peculiar hydrolysis profile, including mostly penicillins and carbapenems. Regarding bla(OXA-23) in A. radioresistens and bla(OXA-134) in A. lwoffii, these genes were not expressed (or expressed at a non-significant level) in their host. Detection of these ß-lactamase genes might be used as a useful tool for accurate identification of these Acinetobacter species.

Cytokine response and reactive oxygen species production after low- and intermediate-risk surgery.

BACKGROUND: Cytokines are secreted locally in response to surgery and may be released into the systemic circulation. Reactive oxygen species (ROS) production is involved in various inflammatory conditions. The aims of the study were to examine the magnitude of surgical stress on the modulation of immune response and ROS production. METHODS: Patients undergoing low- and intermediate-risk surgery (n=32) were enrolled. Blood samples for tumor necrosis factor (TNF)α, interleukin (IL)1ß and IL10 assays were obtained before anesthesia, immediately after extubation, at 24 and 72 h after surgery. Measurement in whole-blood cultures of ex vivo lipopolysaccharide (LPS) and Staphylococcus aureus Cowan (SAC)-stimulated production of cytokines was carried out. The pro-oxidant potency of the whole serum was assessed in human umbilical vein endothelial cells using a fluorescent probe after stimulation by the plasma collected at the same time intervals. RESULTS: TNFα, IL1ß and IL10 did not increase significantly after surgery in either group. Whole-blood cultures response to LPS and SAC stimulation decreased for IL1ß at the end of surgery in the two groups and returned to normal within 24 h after surgery. LPS- and SAC-induced IL10 production increased significantly at 24 h in the low-risk surgery group. ROS production was greater after more stressful surgery and was correlated to morphine consumption. CONCLUSION: Cytokine release in the systemic circulation was not well correlated to the magnitude of surgical stress, whereas transient immune hyporesponsiveness was seen after moderately stressful surgery. ROS production might be a more accurate indicator of the severity of surgical trauma.

[Coagulation disorders after traumatic brain injury: pathophysiology and therapeutic implications]. / Troubles de la coagulation lors du traumatisme cranio-encéphalique: physiopathologie et conséquences thérapeutiques.

Early activation of coagulation is common after traumatic brain injury. Its origin is probably mainly intracerebral, due to tissue factor release from the injured brain. Abnormalities in blood coagulation tests are associated with poor neurological prognosis. Coagulation activation may induce disseminated intravascular coagulation and fibrinolysis. Disseminated intravascular coagulation is linked to brain ischemia caused by intravascular microthrombosis. This review will focus on pathophysiology of coagulation disorders after traumatic brain injury, and on their implications for therapeutic approaches.