Simultaneous CT angiography and whole-body CT is an effective imaging approach before multiorgan retrieval.

PURPOSE: To assess the role of whole-body computed tomography (CT) for determining morphological suitability before multiorgan retrieval (MOR) in brain dead patients. MATERIALS AND METHODS: Fifty-one clinically brain dead patients (21 women, 30 men; mean age 61 year±15) were included in this prospective, single center study. All patients had CT angiography of the brain and whole-body CT examination. CT images were evaluated for the presence of morphological abnormalities of lungs, liver and other abdominal organs and presence of vascular anatomical variants. The results of CT examinations were compared to intraoperative findings observed during organ harvesting and/or the results of histopathological analysis of biopsy specimens. The impact of whole-body CT examination on the harvesting process was evaluated. RESULTS: Ninety-five percent of vascular anatomical variants that were found intraoperatively were depicted on CT. CT density measurements predicted surgical finding of steatosis in 80% of patients. Whole-body CT changed the MOR strategy in 21/51 patients (41%) including 3 MOR cancellations and 8 grafts refusals, whereas organ harvesting was continued in 10 patients after histopathological analysis was performed. CONCLUSION: Selection of potential graft donors using whole-body CT is reliable and improves graft selection during MOR.

Gender differences in the association between stop-signal reaction times, body mass indices and/or spontaneous food intake in pre-school children: an early model of compromised inhibitory control and obesity.

BACKGROUND: Poor inhibitory control is associated with overeating and/or obesity in school-age children, adolescents and adults. The current study examined whether an objective and reliable marker of response inhibition, the stop-signal reaction time (SSRT), is associated with body mass index (BMI) z-scores and/or food intake during a snack test in pre-school children. METHODS: The current sample consisted of 193 pre-school children taking part in a longitudinal study of early brain development (Maternal Adversity, Vulnerability and Neurodevelopment (the MAVAN project)). Linear mixed-effect models were used to examine whether the SSRT measured at age 48 months associated with BMI z-scores and/or dietary intake during a laboratory-based snack test. RESULTS: After controlling for significant covariates including maternal BMI, there was a significant gender by SSRT interaction effect in predicting 48-month BMI z-scores. Post-hoc analysis revealed an association between longer SSRTs (poor response inhibition) and higher BMIs in girls but not boys. Across both girls and boys, longer SSRTs were associated with greater intake of carbohydrates and sugars during the snack test. The association between SSRT scores and BMI z-scores in girls was not statistically mediated by carbohydrate or sugar intake. CONCLUSIONS: At 48 months of age, slower response inhibition on the Stop-Signal Task associates with higher BMI z-scores in girls, and with higher intake of carbohydrates and sugars during a snack test across both genders. Ongoing follow-up of these children will help clarify the implications of these associations for longer term macronutrient intake, eating-related pathology and/or pathological weight gain over time.

Moderators of psychological recovery from benign cancer screening results.

OBJECTIVE: The sudden confrontation of a potential health threat such as cancer, even after the diagnosis turns out to be benign, can have enduring adverse psychological consequences, including persistent anxiety, cancer fears, and other manifestations of psychological distress. The present study examines factors that potentially moderate psychological recovery among women who face a breast cancer threat. DESIGN: Participants were adult women had just received a benign outcome from a breast cancer diagnostic procedure that had been conducted because of suspicion of breast cancer (a non-conclusive mammography or ultrasonography result, a referral from their doctor because of pain or family history, detection of a lump, a 6-month follow-up appointment after a breast abnormality from a previous screening or diagnostic procedure, or a fluid leak from one or both breasts). We measured several psychological traits at Time 1 (right after receipt of the "no cancer" feedback) and then each month for the next 3 months. Analyses examined the factors that hindered or facilitated psychological recovery from the cancer threat. RESULTS: Results showed that trait anxiety and family history of cancer hindered recovery and that older age and optimism facilitated recovery and lessened adverse psychological consequences. Self-regulatory strategies such as planful problem-solving, positive reappraisal, and mastery facilitated recovery. CONCLUSIONS: Our findings shed light on the factors that are implicated in psychological recovery from a benign breast cancer outcome after a diagnostic procedure (ultrasonography, repeat or initial mammography, stereotactic biopsy, fine-needle aspiration, or ultrasound-guided biopsy). Those factors could be used to identify women who may experience prolonged psychological distress, so as to assist them when they face stressful diagnostic concerns.

The optimal aminoglycoside and its dosage for the treatment of severe Enterococcus faecalis infection. An experimental study in the rabbit endocarditis model.

Aminoglycosides are recommended for the treatment of Enterococcus faecalis infections, especially in severe and bacteremic infection. However, the optimal aminoglycoside or the optimal dosage remains uncertain. This study aimed to compare the activity of four aminoglycosides against E. faecalis (gentamicin, netilmicin, tobramycin, and amikacin) and two dosages of gentamicin. One clinical strain of E. faecalis was used to induce aortic endocarditis in the study rabbits. Each aminoglycoside was infused daily over 3 days with a computer-regulated flow simulating human pharmacokinetics of 15 mg/kg/day for amikacin, 6 mg/kg/day for netilmicin, and 3 mg/kg/day for gentamicin and tobramycin. Additionally, two dosages of gentamicin (simulating 3 or 6 mg/kg/day) were compared over 1 or 3 days of treatment. The in vivo efficacy was assessed according to the bacterial count in vegetations, in comparison with a control group. Of the four aminoglycosides tested, only gentamicin and netilmicin showed significant antibacterial efficacy after 3 days of treatment. After only 1 day of treatment, the high dosage of gentamicin (6 mg/kg/day) was more effective than the standard dosage (3 mg/kg/day). Among the tested aminoglycosides, gentamicin showed the best efficacy, with the best results after 24 h of treatment for the highest dosage.

Measurement and interpretation of hand hygiene compliance rates: importance of monitoring entire care episodes.

Our objective was to assess the importance of monitoring hand hygiene compliance (HHC) during series of successive contacts with patients or surroundings for measurement and interpretation of the compliance rates. A direct observational study of HHC was performed in four intensive care units (ICUs) and four healthcare settings with non-intensive care wards (NICWs). Hand hygiene (HH) opportunities were differentiated into two categories: extra-series opportunities (ESOs) (before or after a single contact, and before the first contact or after the last contact of a series of successive contacts) or as intra-series opportunities (ISOs) (from the opportunity following the first contact to the opportunity preceding the last in the same series). In all, 903 opportunities of HH were performed in ICUs and 760 in NICWs. The proportion of ISOs was 46.0% in ICUs and 22.9% in NICWs. The overall HHC was significantly higher in NICWs than in ICUs (61.2% vs 47.5%, P<0.00001). The HHC was significantly higher for ESOs than for ISOs (67.7% vs 28.5%, P<0.00001). The HHC for ISOs was significantly higher in ICUs (32.2% vs 19.0%, P<0.005). If the distribution of categories of HH opportunities observed in NICWs had been the same as in ICUs, the overall HHC would have been similar in NICWs (46.4%) and in ICUs (47.5%). Monitoring HHC during entire care episodes in series of successive contacts is necessary to avoid a strong overestimation of the overall compliance rates. Concurrently, comparison of compliance data should take into account the proportion of ISOs included in the evaluation study.

The evolution of nutritional status of geriatric patients without cachexia is associated with food intake in sub-acute care.

OBJECTIVES: To determine if changes in patients' nutritional status during hospitalization are related to daily energy and protein intakes when cachectic/inflammatory conditions are controlled for. DESIGN: Prospective study. SUBJECTS: A total of 32 non-cachectic patients (21 women; 65-92 y). METHODS: Nutritional status was evaluated at admission and discharge using the Protein-Energy Malnutrition Index which includes BMI, %IBW, TS, MAC, albumin, hemoglobin and lymphocyte count. Food intake was assessed 3 meals/day every other day for an average of 46.2 +/- 14.6 meals/participant. RESULTS: In all, 47% of the study sample was malnourished at admission. Nutritional status improved in 73% of patients who had been identified as malnourished and in 30 % of non-malnourished patients at admission. Total energy intake correlated with improvements in BMI, %IBW and total lymphocyte count (all p < 0.04). Improvement in PEMI score for the whole group was associated with functional status (p < 0.05). Controlling for this variable, energy (kj/kg body weight) and protein (g/kg body weight) intakes correlated positively with improvements in BMI, %IBW and MAC (Energy: partial r = 0.644, 0.624, 0.466 respectively; Protein: partial r = 0.582, 0.554, 0.433 respectively; all p < 0.05). CONCLUSIONS: Results from this study offer strong evidence that when cachectic/inflammatory conditions are controlled for, standard nutrition care is compatible with the maintenance or improvement of nutritional status during the hospital stay.

Nutritional implications of patient-provider interactions in hospital settings: evidence from a within-subject assessment of mealtime exchanges and food intake in elderly patients.

OBJECTIVE: To examine the nutritional implications of the interactions taking place between patients and care providers during mealtimes in hospital settings. Specifically, we tested research propositions that the amount and nature of interpersonal behaviours exchanged between patients and providers impact patients' food intake. These propositions were derived from prior evidence of social influences on eating behaviour and a well-established framework that identifies two fundamental modalities of human interaction: striving for mastery and power (agency) and efforts to promote union with others (communion). DESIGN: In a within-subject naturalistic study, participants were observed on multiple meals (n=1477, 46.2 meals/participant on average), during which participants' and providers' agency- and communion-related behaviours and patients' protein and energy intake were recorded. Meal-level frequency and complementarity of patients' and providers' behaviours were computed to test research propositions. SETTING: Dining room of a geriatric rehabilitation unit. SUBJECTS: Thirty-two elderly patients (21 females, mean age:78.8, 95% CI: 76.4, 81.1). RESULTS: Meal-level frequency of patient-provider exchanges (P=0.016) and patients' agency-related behaviours (P=0.029), as well as mutual reciprocation of patients' and providers' communion-related behaviours (P=0.015) on a given meal were positively linked to protein intake. Higher energy intake was found during meals where patients expressed more agency-related behaviours (P=0.029). CONCLUSION: Results present evidence that the amount and nature of patient-provider interpersonal exchanges on a given meal influence the nutritional quality of food intake in hospitalized elderly. They provide insights into how to improve the design and delivery of routine care to this malnutrition-prone population. SPONSORSHIP: This study was supported by the Canadian Institutes of Health Research (Operating grant to Laurette Dubé, Doctoral Fellowship to Catherine Paquet) the Fonds de la Recherche en santé du Québec and by the Danone Institute (Doctoral fellowship to Danielle St-Arnaud McKenzie).

Light-induced chaotic rotations in nematic liquid crystals.

Various nonlinear rotation regimes are observed in an optically excited nematic liquid-crystal film under boundary conditions (for the light and material) that are invariant by rotation. The excitation light is circularly polarized, the intensity profile is circularly symmetric, and the beam diameter at the sample location is a few times smaller than the cell thickness. A transition to chaos via quasiperiodicity is identified when the light intensity is taken as the control parameter. Transverse nonlocal effects are suggested to be the cause of the observed dynamics, and a simple model consisting of a collection of coupled rotators is developed to provide a qualitative explanation.

[Anthracycline-induced heart failure aggravated by pregnancy. Survival after cardiac assistance with artificial heart device and heart transplantation]. / Myocardiopathie aux anthracyclines décompensée par une grossesse. Guérison par transplantation cardiaque après assistance temporaire par coeur artificiel.

We report a case of a young woman suffering from a steady anthracycline-induced myocardiopathy with a decreased left ventricular function on echocardiography. A pregnancy was initiated, without worsening of the cardiopathy until 34 weeks. Nine days after delivery, an acute heart failure was observed leading to heart transplantation after cardiac assistance with heart cardiac device. As pregnancy is an extended stress test for a chronic failing heart, a multidisciplinary decision of pregnancy initiation and follow up should be preferred in pre and postpartum period, when such a cardiopathy exists.

On Jacobian matrices for flows.

We present a general method for constructing numerical Jacobian matrices for flows discretized on a Poincaré surface of section. Special attention is given to Hamiltonian flows where the additional constraint of energy conservation is explicitly taken into account. We demonstrate the approach for a conservative dynamical flow and apply the technique for the general detection of periodic orbits.

Gas embolism: an exceptional complication of radial arterial catheterization.

BACKGROUND: We report a rare complication of radial arterial catheterization in a 74-year-old man who had undergone retroperitoneal surgery for an infra-renal aortic aneurysm. A right subclavian venous catheter and a right radial artery catheter were inserted for hemodynamic monitoring. RESULTS: The patient suddenly went into a coma, with dyspnea and bradycardia, 1 day postsurgery, as a result of a cerebral gas embolism produced by the accidental entry of pressurized air into the artery via the arterial catheter. Cerebral Magnetic Resonance Imaging revealed multiple, diffuse brain lesions. Six months later the patient still had a left hemiparesis and a cognitive deficit. He walks with assistance. CONCLUSION: Misuse of an arterial catheter can lead to a severe gas embolism. The infusion system used to flush arterial catheters should be checked regularly to ensure it contains no gas.

Optically induced dynamics in nematic liquid crystals: The role of finite beam size.

We report on the influence of a finite beam size on the molecular reorientation dynamics when a nematic liquid crystal film is excited by a laser beam. We present experimental evidence of a new class of nonlinear dynamics when the excitation is a Gaussian shaped, circularly polarized laser beam at normal incidence. Various nonlinear regimes, periodic, quasiperiodic, intermittent, and possibly chaotic, are observed. A physical interpretation based on walk-off effects is proposed and its implications on current research in the field are discussed.

Optically induced dynamics in nematic liquid crystals: the role of twist deformation and asymmetry.

We present a theoretical study of optically induced dynamics in a homeotropic nematic liquid crystal excited at normal incidence. By retaining the first symmetric and antisymmetric reorientation modes, the dynamical equations are reduced to a four-dimensional problem. The main advantage of this minimal approach is to emphasize the role of twisted mode and asymmetry of the light-induced molecular reorientation in a manner suitable for a clear physical interpretation. Theoretical results are compared with experiments in the particular case of circularly polarized light beams to show the physical origin of mode competition and of the breakdown of chiral and longitudinal symmetry. The model successfully describes previous experimental studies such as time-dependent three-dimensional molecular dynamics, light-induced stabilized helical reorientation, and in-plane precession regime in achiral nematics. While a recent experiment has revealed a new spatiotemporal transition, the model succeeds to describe all the features of such a bifurcation pointing out anew the importance of asymmetry. Finally, the first quantitative description of the appearance of a giant mirrorless optical bistability when twisted reorientation modes are excited is demonstrated. A qualitative physical interpretation is suggested for all these phenomena.

[Potential advantages a new syringe pump system]. / Avantages potentiels d'un nouveau système de pousse-seringues.

OBJECTIVES: To evaluate what could be the benefit in terms of alarm suppression, of a new syringe pumps system, which allows automatic relay without alarms. PATIENTS AND METHODS: We have prospectively recorded the nature and the mode of relay of all syringe pumps for administration of drugs to patients in two ICU. The perfusion regimen was studied in 61 patients over the complete duration of their stay in two ICU. Alarms were also recorded in one ICU room, over 13 days consecutive. The records were processed off-line with an automatic detection-recognition system in order to assess the origin of each alarm. Accordingly, the amount of alarm corresponding to monitor, ventilator and syringe pumps was computed. RESULTS: We found that syringe pumps, which would provide automatic relays without alarm, would suppress 17% of alarms in ICU and automatize 65% of the relay procedures, which are usually performed often in emergency, on response to the end of perfusion alarm. CONCLUSION: New syringe pumps allow both reduction of alarms in ICU and a better management of nurse workload. Indeed syringe relay can be planned in advance.

Targeting unknown and unstable periodic orbits.

We present a method to target and subsequently control (if necessary) orbits of specified period but otherwise unknown stability and position. For complex systems where the dynamics is often mixed [e.g., coexistence of regular and chaotic regions in area-preserving (Hamiltonian) systems], this targeting algorithm offers a way to not only gently bring the system from the chaotic domain to an unstable periodic orbit (where control is applied), but also to access stable regions of phase space (where control is not necessary) from within the stochastic regions. The technique is quite general and applies equally well to dissipative or conservative discrete maps and continuous flows.

[Multimodal monitoring of head injuries in children]. / Monitorage multimodal chez l'enfant traumatisé crânien.

As in the case of adults, there are three main goals in the monitoring of severe head trauma in children: to prevent or minimize the apparition of secondary lesions, to optimize treatment, to help make precise prognosis. The basic monitoring is composed of repeated clinical examinations, brain radiological imaging and control of vital parameters (blood pressure, temperature, PaO2 (SpO2), PaCO2 (FETCO2), haemoglobin, haematocrit. On the other hand, during specific brain monitoring, the brain perfusion (TCD, intracranial pressure), the electrical activity of the brain and sometimes the brain oxygenation (SvjO2) are controlled. The data obtained from the brain monitoring must always be interpreted carefully. A child with a severe head trauma, in ICU, always requires constant and competent medical attention.

In vivo efficacy of continuous infusion versus intermittent dosing of ceftazidime alone or in combination with amikacin relative to human kinetic profiles in a Pseudomonas aeruginosa rabbit endocarditis model.

Ceftazidime and amikacin were administered in a Pseudomonas aeruginosa rabbit endocarditis model using computer-controlled intravenous (iv) infusion pumps to simulate human serum concentrations for the following regimens: continuous (constant rate) infusion of 4, 6 or 8 g of ceftazidime over 24 h or intermittent dosing of 2 g every 8 h either alone or in combination with amikacin (15 mg/kg once daily). The in vivo activities of these regimens were tested on four Pseudomonas aeruginosa strains. Animals were killed 24 h after the beginning of treatment. Efficacy was assessed by comparing the effects of the different groups on bacterial counts in vegetations for each strain tested. For a susceptible reference strain (ATCC 27853; MICs of ceftazidime and amikacin 1 and 2 mg/L, respectively), continuous infusion of 4 g alone or with amikacin was as effective as intermittent dosing with amikacin. For a clinical isolate producing an oxacillinase (MICs of ceftazidime and amikacin 8 and 32 mg/L, respectively), continuous infusion of 6 g was equivalent to intermittent dosing. For a clinical isolate producing a TEM-2 penicillinase (MIC of ceftazidime and amikacin 4 mg/L), continuous infusion of 6 g, but not intermittent dosing, had a significant in vivo effect. For a clinical isolate producing an inducible, chromosomally encoded cephalosporinase (MIC of ceftazidime and amikacin 8 and 4 mg/L, respectively), neither continuous infusion nor intermittent dosing proved effective. Determination of ceftazidime concentrations in vegetations showed that continuous infusion produced tissue concentrations at the infection site far greater than the MIC throughout the treatment. It is concluded that continuous infusion of the same total daily dose provides significant activity as compared with fractionated infusion. This study confirms that a concentration of 4-5 x MIC is a reasonable therapeutic target in most clinical settings of severe P. aeruginosa infection.

Clinical predictors of health-related quality of life depend on asthma severity.

The National Asthma Education and Prevention Program guidelines define asthma severity before treatment by lung function and symptoms. It has been assumed, but not demonstrated, that improvement in these measures would translate into improvement in health-related quality of life (HRQL). Because HRQL is an important outcome in asthma management, we asked what are the determinants of HRQL? To address this question, we retrospectively analyzed HRQL data, as measured by the Juniper Asthma Quality of Life Questionnaire, in subjects with mild versus moderate-severe asthma from two clinical trials. We examined whether these traditional clinical outcomes have different relationships to HRQL depending on asthma severity. We also assessed whether the relationship between clinical outcomes and HRQL in subjects with moderate-severe asthma would change when subjects improved to mild-moderate disease with controller medication treatment. Lung function was not an independent predictor or determinant of HRQL at any level of asthma severity, whereas intensity of shortness of breath predicted HRQL at all levels of asthma severity. Rescue beta-agonist use independently predicted HRQL in subjects with mild asthma, but not in those with moderate-severe asthma. In subjects with moderate-severe asthma who improved to mild-moderate disease with controller treatment, rescue beta-agonist use predicted HRQL. We conclude that the independent determinants of HRQL vary according to asthma severity and change with asthma treatment.