Relevance of using a compressive preload in the cervical spine: an experimental and numerical simulating investigation.

UNLABELLED: Simulating compressive action of muscles, a follower load attends to reproduce a more physiological biomechanical behaviour of the cervical spine. Only few experimental studies reported its influence on kinematics and intradiscal pressure in the cervical spine. STUDY DESIGN: In vitro human cadaveric and numerical simulating evaluation of a compressive preload in the cervical spine. OBJECTIVES: To analyse the influence of a compressive follower preload on the biomechanical behaviour of the cervical spine. METHODS: The present study was divided into two parts: part 1: in vitro investigation; part 2: numerical simulating analysis. Part 1: Twelve human cadaveric spines from C2 to T2 were evaluated intact and after application of a 50-N follower load. All tests were performed under load control by applying pure moments loading of 2 Nm in flexion/extension (FE), axial rotation (AR) and lateral bending (LB). Three-dimensional displacements were measured using an optoelectronic system, and intradiscal pressures were measured at two levels. Part 2: Using a 3D finite element model, we evaluated the influence of a 50- and 100-N compressive preload on intradiscal loads, facets forces and ranges of motion. Different positions of the follower load along the anteroposterior axis (±5 mm) were also simulated. RESULTS: Part 1: Mean variation of cervical lordosis was 5° ± 3°. The ROM slightly increased in FE, whereas it consistently decreased in AR and LB. Coupled lateral bending during AR was also reduced. Increase in hysteresis was observed on load-displacement curves only for AR and LB. Intradiscal pressures increased, but the aspect of load-pressure curves was altered in AR and LB. Part 2: Using the FE model, only minimal changes in ROM were noted following the simulation of a 50-N compressive load for the three loading conditions. Compared to intact condition, <10% variation was observed with regard to the different magnitude and positioning simulated. Intradiscal loads and facets forces were systematically increased by applying compressive preload. CONCLUSIONS: Although the follower load represents an attractive option to apply compressive preload during experimental tests, we found that this method could affect the native biomechanical behaviour of spine specimen depending on which movement was considered. Only minimal effects were observed in FE, whereas significant changes in kinematics and intradiscal pressures were observed for AR and LB.

Pedicle subtraction osteotomy in the lumbar spine: indications, technical aspects, results and complications.

Pedicle subtraction osteotomy (PSO) consists of creating posteriorly trapezoidal shape of a vertebra, usually L3 or L4, in order to recreate lordosis in the lumbar spine. It is usually indicated to treat rigid kyphotic lumbar spine associated with sagittal imbalance and due to degenerative changes or to iatrogenic flat back. PSO is technically demanding with high rates of complications and should be performed by experienced teams. We presently report our experience about PSO performed in the lumbar spine (below L1) through a series of 25 cases with a special focus on technical aspects and complications associated with the surgical procedure. Mean age was 64 ± 11 years old. PSO was performed at L4 in the majority of cases. Mean blood loss was 1,070 ± 470 ml, and mean duration of the surgery was 241 ± 44 min. VAS decreased from 7.5 ± 2 preoperatively to 3.2 ± 2.5 at 1 year, and ODI decreased from 64 ± 12 preoperatively to 32 ± 18 at 1 year, p < 0.05. Mean gain of lordosis after PSO varies from 20° to 40° and was measured to 27° ± 10° on average. Lumbar lordosis (T12-S1) was measured to 21° ± 10° preoperatively to 50° ± 11° postoperatively at 1 year, p < 0.05. A total of five major complications (20 %) were observed (two mechanical, one neurological and two infections) necessitating five reoperations. In conclusion, PSO was highly efficient to restore lumbar lordosis and correct sagittal imbalance. It was associated with a non-negligible, but acceptable rate of complications. To limit the risk of mechanical complications, we recommend fusing the adjacent disks whatever the approach (PLIF/TLIF/XLIF). Most complications can be reduced with adequate environment, informed anesthesiologists and experienced surgical team.

Neuromuscular blockers in early acute respiratory distress syndrome.

BACKGROUND: In patients undergoing mechanical ventilation for the acute respiratory distress syndrome (ARDS), neuromuscular blocking agents may improve oxygenation and decrease ventilator-induced lung injury but may also cause muscle weakness. We evaluated clinical outcomes after 2 days of therapy with neuromuscular blocking agents in patients with early, severe ARDS. METHODS: In this multicenter, double-blind trial, 340 patients presenting to the intensive care unit (ICU) with an onset of severe ARDS within the previous 48 hours were randomly assigned to receive, for 48 hours, either cisatracurium besylate (178 patients) or placebo (162 patients). Severe ARDS was defined as a ratio of the partial pressure of arterial oxygen (PaO2) to the fraction of inspired oxygen (FIO2) of less than 150, with a positive end-expiratory pressure of 5 cm or more of water and a tidal volume of 6 to 8 ml per kilogram of predicted body weight. The primary outcome was the proportion of patients who died either before hospital discharge or within 90 days after study enrollment (i.e., the 90-day in-hospital mortality rate), adjusted for predefined covariates and baseline differences between groups with the use of a Cox model. RESULTS: The hazard ratio for death at 90 days in the cisatracurium group, as compared with the placebo group, was 0.68 (95% confidence interval [CI], 0.48 to 0.98; P=0.04), after adjustment for both the baseline PaO2:FIO2 and plateau pressure and the Simplified Acute Physiology II score. The crude 90-day mortality was 31.6% (95% CI, 25.2 to 38.8) in the cisatracurium group and 40.7% (95% CI, 33.5 to 48.4) in the placebo group (P=0.08). Mortality at 28 days was 23.7% (95% CI, 18.1 to 30.5) with cisatracurium and 33.3% (95% CI, 26.5 to 40.9) with placebo (P=0.05). The rate of ICU-acquired paresis did not differ significantly between the two groups. CONCLUSIONS: In patients with severe ARDS, early administration of a neuromuscular blocking agent improved the adjusted 90-day survival and increased the time off the ventilator without increasing muscle weakness. (Funded by Assistance Publique-Hôpitaux de Marseille and the Programme Hospitalier de Recherche Clinique Régional 2004-26 of the French Ministry of Health; ClinicalTrials.gov number, NCT00299650.)

Compensatory mechanisms contributing to keep the sagittal balance of the spine.

INTRODUCTION: Aging spine is characterized by facet joints arthritis, degenerative disc disease, bone remodeling and atrophy of extensor muscles resulting in a progressive kyphosis of the lumbar spine. OBJECTIVE: The aim of this paper is to describe the different compensatory mechanisms for patients with severe degenerative lumbar spine. MATERIAL AND METHODS: According to the severity of the imbalance, three stages are observed: balanced, balanced with compensatory mechanisms and imbalanced. For the two last stages, the compensatory mechanisms permit to limit the consequences of loss of lumbar lordosis on global sagittal alignment and therefore contribute to keep the sagittal balance of the spine. RESULTS: The basic concept is to extend adjacent segments of the kyphotic spine allowing for compensation of the sagittal unbalance but potentially inducing adverse effects. CONCLUSION: Finally, we propose a three-step algorithm to analyze the global balance status and take into consideration the presence of the compensatory mechanisms in the spinal, pelvic and lower limb areas.

Effect of statin therapy on mortality in patients with ventilator-associated pneumonia: a randomized clinical trial.

IMPORTANCE: Observational studies have reported that statin use may be associated with improved outcomes of various infections. Ventilator-associated pneumonia (VAP) is the most common infection in the intensive care unit (ICU) and is associated with substantial mortality. OBJECTIVE: To determine whether statin therapy can decrease day-28 mortality in patients with VAP. DESIGN, SETTING, AND PARTICIPANTS: Randomized, placebo-controlled, double-blind, parallel-group, multicenter trial performed in 26 intensive care units in France from January 2010 to March 2013. For power to detect an 8% absolute reduction in the day-28 mortality rate, we planned to enroll 1002 patients requiring invasive mechanical ventilation for more than 2 days and having suspected VAP, defined as a modified Clinical Pulmonary Infection Score of 5 or greater. The futility stopping rules were an absolute increase in day-28 mortality of at least 2.7% with simvastatin compared with placebo after enrollment of the first 251 patients. INTERVENTIONS: Participants were randomized to receive simvastatin (60 mg) or placebo, started on the same day as antibiotic therapy and given until ICU discharge, death, or day 28, whichever occurred first. MAIN OUTCOMES AND MEASURES: Primary outcome was day-28 mortality. Day-14, ICU, and hospital mortality rates were determined, as well as duration of mechanical ventilation and Sequential Organ Failure Assessment (SOFA) scores on days 3, 7, and 14. RESULTS: The study was stopped for futility at the first scheduled interim analysis after enrollment of 300 patients, of whom all but 7% in the simvastatin group and 11% in the placebo group were naive to statin therapy at ICU admission. Day-28 mortality was not lower in the simvastatin group (21.2% [95% CI, 15.4% to 28.6%) than in the placebo group (15.2% [95% CI, 10.2% to 22.1%]; P = .10; hazard ratio, 1.45 [95% CI, 0.83 to 2.51]); the between-group difference was 6.0% (95% CI, -3.0% to 14.9%). In statin-naive patients, day-28 mortality was 21.5% (95% CI, 15.4% to 29.1%) with simvastatin and 13.8% (95% CI, 8.8% to 21.0%) with placebo (P = .054) (between-group difference, 7.7% [95%CI, -1.8% to 16.8%). There were no significant differences regarding day-14, ICU, or hospital mortality rates; duration of mechanical ventilation; or changes in SOFA score. CONCLUSIONS AND RELEVANCE: In adults with suspected VAP, adjunctive simvastatin therapy compared with placebo did not improve day-28 survival. These findings do not support the use of statins with the goal of improving VAP outcomes. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01057758.

Ventilator-associated pneumonia and ICU mortality in severe ARDS patients ventilated according to a lung-protective strategy.

INTRODUCTION: Ventilator-associated pneumonia (VAP) may contribute to the mortality associated with acute respiratory distress syndrome (ARDS). We aimed to determine the incidence, outcome, and risk factors of bacterial VAP complicating severe ARDS in patients ventilated by using a strictly standardized lung-protective strategy. METHODS: This prospective epidemiologic study was done in all the 339 patients with severe ARDS included in a multicenter randomized, placebo-controlled double-blind trial of cisatracurium besylate in severe ARDS patients. Patients with suspected VAP underwent bronchoalveolar lavage to confirm the diagnosis. RESULTS: Ninety-eight (28.9%) patients had at least one episode of microbiologically documented bacterial VAP, including 41 (41.8%) who died in the ICU, compared with 74 (30.7%) of the 241 patients without VAP (P = 0.05). After adjustment, age and severity at baseline, but not VAP, were associated with ICU death. Cisatracurium besylate therapy within 2 days of ARDS onset decreased the risk of ICU death. Factors independently associated with an increased risk to develop a VAP were male sex and worse admission Glasgow Coma Scale score. Tracheostomy, enteral nutrition, and the use of a subglottic secretion-drainage device were protective. CONCLUSIONS: In patients with severe ARDS receiving lung-protective ventilation, VAP was associated with an increased crude ICU mortality which did not remain significant after adjustment.

Cervical disc prosthesis versus arthrodesis using one-level, hybrid and two-level constructs: an in vitro investigation.

INTRODUCTION: The purpose of this experimental study was to analyse cervical spine kinematics after 1-level and 2-level total disc replacement (TDR) and compare them with those after anterior cervical arthrodesis (ACA) and hybrid construct. Kinematics and intradiscal pressures were also investigated at adjacent levels. METHODS: Twelve human cadaveric spines were evaluated in different testing conditions: intact, 1 and 2-level TDR (Discocerv™, Scient'x/Alphatec), 1 and 2-level ACA, and hybrid construct. All tests were performed under load control protocol by applying pure moments loading of 2 N m in flexion/extension (FE), axial rotation (AR) and lateral bending (LB). RESULTS: Reduction of ROM after 1-level TDR was only significant in LB. Implantation of additional TDR resulted in significant decrease of ROM in AR at index level. A second TDR did not affect kinematics of the previously implanted TDR in FE, AR and LB. One and 2-level arthrodesis caused significant decrease of ROM in FE, AR and LB at the index levels. No significant changes in ROM were observed at adjacent levels except for 1-level arthrodesis in FE and hybrid construct in AR. When analysis was done under the displacement-control concept, we found that 1 and 2-constructs increased adjacent levels contribution to global ROMC3-C7 during FE and that IDP at superior adjacent level increased by a factor of 6.7 and 2.3 for 2-level arthrodesis and hybrid constructs, respectively. CONCLUSION: Although 1- and 2-level TDR restored only partially native kinematics of the cervical spine, these constructs generated better biomechanical conditions than arthrodesis at adjacent levels limiting contribution of these segments to global ROM and reducing the amount of their internal stresses.

Sagittal alignment and kinematics at instrumented and adjacent levels after total disc replacement in the cervical spine.

BACKGROUND: The purpose of the study was to report radiological outcomes after total disc replacement (TDR) in the cervical spine through a 24 months follow-up (FU) prospective study with a special focus on sagittal alignment and kinematics at instrumented and adjacent levels. MATERIALS AND METHODS: Thirty-two patients, who sustained one-level TDR with a ball-and-socket arthroplasty (Discocerv(™) implant, Scient'x/Alphatec Spine, USA) were consecutively included in the study. Clinical (visual analogical scale and neck disability index) and radiological parameters were measured preoperatively and postoperatively at 3/6 months, 1-year and 2-year FU. Sagittal alignment, ranges of motion (ROM) and center of rotations (CORs) were analyzed using specific motion analysis software (Spineview(™), Paris, France). Patients CORs were compared with those of a control group of 39 normal and asymptomatic subjects. RESULTS: Both local and C3-C7 lordosis significantly increased postoperatively (+8° and +13° at 2 years, respectively). At instrumented level ROM in flexion-extension (FE) was measured to 10.2° preoperatively versus 7.5° at 1 year and 6.1° at 2 years. There were no differences in ROM at adjacent levels between pre and postoperative assessments. When compared with control group and preoperative measurements, we noted postoperative cranial shift of the COR at instrumented level for patients group. In contrast, there was no difference in CORs location at adjacent levels. CONCLUSION: Through this prospective study, we observed that cervical lordosis consistently increased after TDR. In addition, although ball-and-socket arthroplasty did not fully restore native segmental kinematics with significant reduction of motion in FE and consistent cranial shift of the COR, no significant changes in terms of ROM and CORs were observed at adjacent levels.

Sagittal balance disorders in severe degenerative spine. Can we identify the compensatory mechanisms?

INTRODUCTION: Aging of the spine is characterized by facet joints arthritis, degenerative disc disease and atrophy of extensor muscles resulting in a progressive kyphosis. Recent studies confirmed that patients with lumbar degenerative disease were characterized by an anterior sagittal imbalance, a loss of lumbar lordosis and an increase of pelvis tilt. The aim of this paper was thus to describe the different compensatory mechanisms which are observed in the spine, pelvis and/or lower limbs areas for patients with severe degenerative spine. METHODS: We reviewed all the compensatory mechanisms of sagittal unbalance described in the literature. RESULTS: According to the severity of the imbalance, we could identify three different stages: balanced, balanced with compensatory mechanisms and imbalanced. For the two last stages, the compensatory mechanisms permitted to limit consequences of lumbar kyphosis on the global sagittal alignment. Reduction of thoracic kyphosis, intervertebral hyperextension, retrolisthesis, pelvis backtilt, knee flessum and ankle extension were the main mechanisms described in the literature. The basic concept of these compensatory mechanisms was to extend adjacent segments of the kyphotic spine allowing for compensation of anterior translation of the axis of gravity. CONCLUSIONS: To avoid underestimate the severity of the degenerative spine disorder, it thus seems important to recognize the different compensatory mechanisms from the upper part of the trunk to the lower limbs. We propose a three steps algorithm to analyse the balance status and determine the presence or not of these compensatory mechanisms: measurement of pelvis incidence, assessment of global sagittal alignment and analysis of compensatory mechanisms successively in the spine, pelvis and lower limbs areas.

Evidence of improved surgical outcome following endoscopy for nonfunctioning pituitary adenoma removal.

OBJECT: Because of their size and lateral extension, total removal of nonfunctioning pituitary adenomas (NFPAs) remains a challenge and postoperative tumor remnants are frequent. Endoscopy has improved the surgeon's view; however, its superiority in terms of surgical outcome remains undetermined. The authors' aim in this study was to compare the clinical results and morbidity between microscopic and endoscopic techniques in 164 patients with NFPAs. METHODS: Tumoral (3D MR imaging), endocrinological, and ophthalmological results and morbidity were compared between 2 groups of 82 patients with newly diagnosed NFPAs surgically treated via either a sublabial microscopic approach (Group B) or a fully endonasal endoscopic technique (Group A). RESULTS: The groups showed no difference in terms of clinical features, tumor size, or cavernous sinus invasion (p > 0.05). One year postoperatively, the quality of resection was significantly improved in Group A (gross-total removal [GTR]: 74% vs 50% in Group B, p = 0.002) with greater control of lateral extension (Knosp Grade 2: GTR 88.2% vs 47.8% in Group B, p = 0.02; Knosp Grade 3: 67.9% vs 16.7% in Group B, p < 0.001) and suprasellar extension (tumor height 20-30 mm: GTR 76% vs 53% in Group B, p = 0.01). Endocrinological outcome in patients with a partial deficiency in anterior pituitary function preoperatively was significantly better in Group A (improvement 56% vs 25% in Group B, stabilization 22% vs 46%, and aggravation 22% vs 29%; p = 0.01). Among the ophthalmologically symptomatic patients, 100% from Group A improved compared with 93% in Group B (p = 0.35). Lastly, no significant difference was found regarding morbidity. These data were supported by the literature in which the GTR rate is consistently higher for endoscopy compared with microscopy. CONCLUSIONS: In this large series of patients with NFPAs, endoscopy improved the quality of resection and endocrinological outcome. Larger studies focusing on the impact of these promising results on the long-term recurrence of NFPAs are warranted.

Early onset pneumonia in severe chest trauma: a risk factor analysis.

BACKGROUND: The development of an early-onset pneumonia (EOP), occurring within the first 72 hours after admission, represents a critical event in severe thoracic trauma population. The aim of this study was to determine risk factors associated with the occurrence of this complication in this specific population. METHODS: A retrospective review of a prospective implemented trauma registry was conducted during a 4-year period in a Level I trauma center. Over the study period, 223 severely injured patients were admitted with severe thoracic trauma (Injury Severity Score >16 and Thorax Abbreviated Injury Score >2). Multiple logistic regression analysis was used to determine the independent predictors of EOP based on the clinical characteristics and the initial management both in the field and after admission in the trauma center. RESULTS: Independent predictors of EOP were the necessity of intubation and mechanical ventilation in the field (adjusted odds ratio [OR]: 11.8; 95% confidence interval [CI]: 4.3-32.7), a history of aspiration (OR: 28.6; 95% CI: 4.0-203.5), the presence of pulmonary contusion (OR: 7.0; 95% CI: 2.0-23.9), and the occurrence of a hemothorax (OR: 3.2; 95% CI: 1.4-7.6). CONCLUSION: These results emphasize the influence of prehospital and early factors in the further occurrence of EOP, which allows the development of early and specific clinical management to prevent it.

A lung ultrasound score for early triage of elderly patients with acute dyspnea.

OBJECTIVES: Lung ultrasound has value in diagnosing dyspnea. The main objective of this study was to evaluate the accuracy of a modified lung ultrasound (MLUS) score to predict the severity of acute dyspnea in elderly patients. METHODS: This was an observational single-centre study including patients over age 64 admitted to the emergency department for acute dyspnea with hypoxia. Participants had an early lung ultrasound performed by a dedicated emergency physician, followed by the usual care by a team blinded to the lung ultrasound results. Patients were allocated by disposition to either a critical care (CC) group (patients who needed admission to the intensive care unit [ICU] and/or who died within 48 h) or a standard care group. RESULTS: Among 137 patients analysed (mean age 79 ± 13 years, 74 [54%] women), 43 (31%) were categorized into the CC group. The time taken to obtain the MLUS was 30 ± 22 min. The area under the receiver operating characteristic curve of the MLUS for predicting the CC group was 0.97 (0.92-0.99; p < 0.01) with a cut-off set strictly above 17 for 93% sensitivity (81-99), 99% specificity (94-100), a positive predictive value of 98% (87-100), a negative predictive value of 97% (91-99), a positive likelihood ratio of 86, a negative likelihood ratio of 0.07, and a diagnostic accuracy of 97% (93-99). In a multivariate analysis, the MLUS was the only independent associated factor for the CC group. CONCLUSION: An early lung ultrasound score can predict the need for ICU admission and/or death within 48 hours in elderly dyspneic patients.

A diagnostic marker set for invasion, proliferation, and aggressiveness of prolactin pituitary tumors.

Although most pituitary tumors are benign, some are invasive or aggressive. In the absence of specific markers of malignancy, only tumors with metastases are considered malignant. To identify markers of invasion and aggressiveness, we focused on prolactin (PRL) tumors in the human and rat. Using radiology and histological methods, we classified 25 human PRL tumors into three groups (non-invasive, invasive, and aggressive-invasive) and compared them with a model of transplantable rat PRL tumors with benign and malignant lineages. Combining histological(mitoses and labeling for Ki-67, P53, pituitary transforming tumor gene (PTTG), and polysialic acid neural cell adhesion molecule) and transcriptomic (microarrays and q-RTPCR) methods with clinical data (post-surgical outcome with case-control statistical analysis), we found nine genes implicated in invasion (ADAMTS6, CRMP1, and DCAMKL3) proliferation (PTTG, ASK, CCNB1, AURKB, and CENPE), or pituitary differentiation (PITX1) showing differential expression in the three groups of tumors (P = 0.015 to 0.0001). A case-control analysis, comparing patients in remission (9 controls) and patients with persistent or recurrent tumors (14 cases) revealed that eight out of the nine genes were differentially up- or downregulated (P = 0.05 to 0.002), with only PTTG showing no correlation with clinical course (P = 0.258). These combined histological and transcriptomic analyses improve the pathological diagnosis of PRL tumors, indicating a reliable procedure for predicting tumor aggressiveness and recurrence potential. The similar gene profiles found between non-invasive human and benign rat tumors, as well as between aggressive-invasive human and malignant rat tumors provide new insights into malignancy in human pituitary tumors.

[Reorganizing departments - an opportunity to formalize procedures for cross-specialty care in public hospitals]. / Le pôle d'activité, une opportunité pour formaliser des processus de soins transversaux à l'hôpital public.

Among the reforms promoted by the Ministry of Health to reverse the compartmentalization within French hospital departments, "new governance" is a core element of the "Hôpital 2007" plan. Public hospitals are free to reorganize their departments into a different and more rational structure. This reorganization requires that the new departments reach a critical size and bring together units according to three complementary approaches: medical, administrative, and cultural. This reorganization process provides an opportunity to improve cross-specialty "individualized" care by formalizing procedures and protocols that help healthcare personnel to cooperate. The success of this reform essentially depends on a real commitment by all staff - workers, professionals, and managers - to improve patient care.

Titanium versus polyetheretherketone implants for vertebral body replacement in the treatment of 77 thoracolumbar spinal fractures.

BACKGROUND: Titanium and polyetheretherketone (PEEK) implants have been used in spinal surgery with low rejection rates. Compared to titanium, PEEK has many advantages, including a density more similar to that of bone, radiolucency, and a lack of artifacts in computed tomography (CT) and magnetic resonance imaging (MRI). In this study, we evaluated the effectiveness of PEEK cages as an alternative to titanium for bone fusion after fractures of the thoracolumbar spine. We also propose a classification to the impaction index. METHODS: We evaluated 77 patients with fractures of the thoracic or lumbar spine who were treated by anterior fixation with titanium cages (TeCorp®) in 46 (59.7%) patients or PEEK (Verte-stak®) in 31 (40.3%) patients from 2006 to 2012 (Neurological Hospital of Lyon). RESULTS: The titanium group achieved 100% fusion, and the PEEK group achieved 96.3% fusion. The titanium systems correlated with higher impact stress directed toward the lower and upper plateaus of the fused vertebrae; there were no nonunions for those treated with titanium group. Nevertheless, there was only one in the PEEK group. There was no significant difference in the pain scale outcomes for patients with ±10 degrees of the sagittal angle. Statistically, it is not possible to associate the variation of sagittal alignment or the impaction with symptoms of pain. The complication rate related to the implantation of cages was low. CONCLUSIONS: Titanium and PEEK are thus equally effective options for the reconstruction of the anterior column. PEEK is advantageous because its radiolucency facilitates the visualization of bone bridges.

Effects of neuromuscular blockers on transpulmonary pressures in moderate to severe acute respiratory distress syndrome.

PURPOSE: To investigate whether neuromuscular blocking agents (NMBA) exert beneficial effects in acute respiratory distress syndrome (ARDS) by reason of their action on respiratory mechanics, particularly transpulmonary pressures (P L). METHODS: A prospective randomised controlled study in patients with moderate to severe ARDS within 48 h of the onset of ARDS. All patients were monitored by means of an oesophageal catheter and followed up for 48 h. Moderate ARDS patients were randomised into two groups according to whether they were given a 48-h continuous infusion of cisatracurium besylate or not (control group). Severe ARDS patients did not undergo randomisation and all received cisatracurium besylate per protocol. The changes during the 48-h study period in oxygenation and in respiratory mechanics, including inspiratory and expiratory P L and driving pressure, were assessed and compared. Delta P L (∆P L) was defined as inspiratory P L minus expiratory P L. RESULTS: Thirty patients were included, 24 with moderate ARDS and 6 with severe ARDS. NMBA infusion was associated with an improvement in oxygenation in both moderate and severe ARDS, accompanied by a decrease in both plateau pressure and total positive end-expiratory pressure. The mean inspiratory and expiratory P L were higher in the moderate ARDS group receiving NMBA than in the control group. In contrast, there was no change in either driving pressure or ∆P L related to NMBA administration. CONCLUSIONS: NMBA could exert beneficial effects in patients with moderate ARDS, at least in part, by limiting expiratory efforts.

Inhaled nitric oxide does not prevent pulmonary edema after lung transplantation measured by lung water content: a randomized clinical study.

STUDY OBJECTIVE: In order to assess the effects of inhaled nitric oxide (iNO) in preventing early-onset lung edema from occurring after lung transplantation, we measured extravascular lung water (EVLW) in a group of lung transplant recipients who were at high risk for developing ischemia-reperfusion-induced lung injury. DESIGN: Prospective, randomized study. SETTINGS: Surgical ICU in a teaching hospital. PATIENTS: Thirty double-lung transplant recipients. INTERVENTIONS: Patients were randomized to receive or not receive 20 ppm iNO at the time of reperfusion (ie, before any occurrence of lung edema). In the NO group, iNO was then administered for a 12-h period. A double-dilution technique was used for the serial assessment of EVLW, intrathoracic blood volume, and cardiac index. Standard hemodynamic and pulmonary parameters were also recorded during the first 3 postoperative days. MEASUREMENTS AND RESULTS: Patients who received iNO did not have a different lung water content compared to control subjects (p = 0.61 [by analysis of variance (ANOVA)]). Blood oxygenation (ie, Pao(2)/fraction of inspired oxygen [Fio(2)] ratio) did not differ between the two groups (p = 0.61 [by ANOVA]). In both groups, EVLW and Pao(2)/Fio(2) ratio dropped significantly over time, regardless of the use of iNO (p < 0.01 [by ANOVA]). CONCLUSIONS: In the population studied, prophylactic iNO that was administered at 20 ppm had no effect on pulmonary edema formation and resolution following lung transplantation.

Type III procollagen is a reliable marker of ARDS-associated lung fibroproliferation.

PURPOSE: A specific biomarker of post-ARDS fibroproliferation could be useful in the identification of patients who could benefit from therapies aiming to modulate fibroproliferation such as corticosteroids.The aim of this prospective study was to determine the best threshold of the N-terminal-peptidetype III procollagen (NT-PCP-III) in non-resolving ARDS to validate this threshold according to the outcome. METHODS: Concerning the best threshold of NT-PCP-III, all consecutive patients with a non-resolving ARDS were included if all the following criteria were fulfilled: moderate to severe ARDS lasting for at least 5 days, lung biopsy performed, serum and alveolar NT-PCP-III obtained within 1 week prior to biopsy, and no documented infection contra-indicating the corticosteroids. In the validation cohort part of the study, patients were included at day 7 if they presented a persistent moderate to severe ARDS. RESULTS: Nineteen of 32 patients had fibroproliferatio nonbiopsy. Serum and alveolar NT-PCP-III were higher in patients with fibroproliferation. Using a threshold of 9 µg/L, alveolar NT-PCP-III had the highest accuracy for diagnosing fibroproliferation (sensitivity = 89.5 % and specificity = 92.3 %). Regarding the 51 patients included in the validation cohort, the mortality rate at day 60 was increased in patients presenting an alveolar NT-PCP-III level higher than 9 µg/L (69 vs. 17 %, p < 0.001). The mean alveolar level of NT-PCP-III on day 7 was 8.1-fold higher in nonsurvivors (p = 0.03). CONCLUSIONS: The determination of NT-PCP-III on BAL done at day 7 in persistent ARDS is able to identify patients with fibroproliferation who could be included in a trial of corticosteroids or any other treatment that might help resolve lung fibroproliferation.

Biomechanical evaluation of cervical lateral mass fixation: a comparison of the Roy-Camille and Magerl screw techniques.

OBJECT: The purpose of this study was to assess human cervical spine pullout force after lateral mass fixation involving two different techniques: the Roy-Camille and the Magerl techniques. Although such comparisons have been conducted previously, because of the heterogeneity of results and the importance of this procedure in clinical practice, it is essential to have data derived from a prospective and randomized biomechanical study involving a sufficient sample of human cervical spines. The authors also evaluated the influence of the sex, the vertebral level, the bone mineral density (BMD), the length of bone purchase, and the thickness of the anterior cortical purchase. METHODS: Twenty-one adult cervical spines were harvested from fresh human cadavers. Computerized tomography was performed before and after placing 3.5-mm titanium lateral mass screws from C-3 to C-6. Pullout forces were evaluated using a material testing machine. The load was applied until the pullout of the screw was observed. A total of 152 pullout tests were available, 76 for each type of screw fixation. The statistical analysis was mainly performed using the Kaplan-Meier survival method. The mean pullout force was 266 +/- 124 N for the Roy-Camille technique and 231 +/- 94 N for the Magerl technique (p < 0.025). For the C3-4 specimen group, Roy-Camille screws were demonstrated to exert a significantly higher resistance to pullout forces (299 +/- 114 N) compared with Magerl screws (242 +/- 97 N), whereas no difference was found between the two techniques for the C5-6 specimen group (Roy-Camille 236 +/- 122 N and Magerl 220 +/- 86 N). Independent of the procedure, pullout strengths were greater at the C3-4 level (271 +/- 114 N) than the C5-6 level (228 +/- 105 N) (p < 0.05). No significant correlation between the cancellous BMD, the thickness of the anterior cortical purchase, the length of bone purchase, and maximal pullout forces was found for either technique. CONCLUSIONS: The difference between pullout forces associated with the Roy-Camille and the Magerl techniques was not as significant as has been previously suggested in the literature. It was interesting to note the influence of the vertebral level: Roy-Camille screws demonstrated greater pullout strength (23%) at the C34 vertebral level than Magerl screws but no significant difference between the techniques was observed at C5-6.

Effectiveness of SAPS III to predict hospital mortality for post-cardiac arrest patients.

PURPOSE: The mortality for patients admitted to intensive care unit (ICU) after cardiac arrest (CA) remains high despite advances in resuscitation and post-resuscitation care. The Simplified Acute Physiology Score (SAPS) III is the only score that can predict hospital mortality within an hour of admission to ICU. The objective was to evaluate the performance of SAPS III to predict mortality for post-CA patients. METHODS: This retrospective single-center observational study included all patients admitted to ICU after CA between August 2010 and March 2013. The calibration (standardized mortality ratio [SMR]) and the discrimination of SAPS III (area under the curve [AUC] for receiver operating characteristic [ROC]) were measured. Univariate logistic regression tested the relationship between death and scores for SAPS III, SAPS II, Sequential Organ Failure Assessment (SOFA) Score and Out-of-Hospital Cardiac Arrests (OHCA) score. Independent factors associated with mortality were determined. RESULTS: One-hundred twenty-four patients including 97 out-of-hospital CA were included. In-hospital mortality was 69%. The SAPS III was unable to predict mortality (SMRSAPS III: 1.26) and was less discriminating than other scores (AUCSAPSIII: 0.62 [0.51, 0.73] vs. AUCSAPSII: 0.75 [0.66, 0.84], AUCSOFA: 0.72 [0.63, 0.81], AUCOHCA: 0.84 [0.77, 0.91]). An early return of spontaneous circulation, early resuscitation care and initial ventricular arrhythmia were associated with a better prognosis. CONCLUSIONS: The SAPS III did not predict mortality in patients admitted to ICU after CA. The amount of time before specialized CPR, the low-flow interval and the absence of an initial ventricular arrhythmia appeared to be independently associated with mortality and these factors should be used to predict mortality for these patients.