Luciana Santos

Online monitoring of pulse pressure variation to guide fluid therapy after cardiac surgery.

BACKGROUND: The arterial pulse pressure variation induced by mechanical ventilation (&Dgr;PP) has been shown to be a predictor of fluid responsiveness. Until now, &Dgr;PP has had to be calculated offline (from a computer recording or a paper printing of the arterial pressure curve), or to be derived from specific cardiac output monitors, limiting the widespread use of this parameter. Recently, a method has been developed for the automatic calculation and real-time monitoring of &Dgr;PP using standard bedside monitors. Whether this method is to predict reliable predictor of fluid responsiveness remains to be determined. METHODS: We conducted a prospective clinical study in 59 mechanically ventilated patients in the postoperative period of cardiac surgery. Patients studied were considered at low risk for complications related to fluid administration (pulmonary artery occlusion pressure <20 mm Hg, left ventricular ejection fraction ≥40%). All patients were instrumented with an arterial line and a pulmonary artery catheter. Cardiac filling pressures and cardiac output were measured before and after intravascular fluid administration (20 mL/kg of lactated Ringer’s solution over 20 min), whereas &Dgr;PP was automatically calculated and continuously monitored. RESULTS: Fluid administration increased cardiac output by at least 15% in 39 patients (66% = responders). Before fluid administration, responders and nonresponders were comparable with regard to right atrial and pulmonary artery occlusion pressures. In contrast, &Dgr;PP was significantly greater in responders than in nonresponders (17% ± 3% vs 9% ± 2%, P < 0.001). The &Dgr;PP cut-off value of 12% allowed identification of responders with a sensitivity of 97% and a specificity of 95%. CONCLUSION: Automatic real-time monitoring of &Dgr;PP is possible using a standard bedside monitor and was found to be a reliable method to predict fluid responsiveness after cardiac surgery. Additional studies are needed to determine if this technique can be used to avoid the complications of fluid administration in high-risk patients.

A population-based morphometric MRI study in patients with first-episode psychotic bipolar disorder: comparison with geographically matched healthy controls and major depressive disorder subjects

OBJECTIVES Many morphometric magnetic resonance imaging (MRI) studies that have investigated the presence of gray matter (GM) volume abnormalities associated with the diagnosis of bipolar disorder (BD) have reported conflicting findings. None of these studies has compared patients with recent-onset psychotic BD with asymptomatic controls selected from exactly the same environment using epidemiological methods, or has directly contrasted BD patients against subjects with first-onset psychotic major depressive disorder (MDD). We examined structural brain differences between (i) BD (type I) subjects and MDD subjects with psychotic features in their first contact with the healthcare system in Brazil, and (ii) these two mood disorder groups relative to a sample of geographically matched asymptomatic controls. METHODS A total of 26 BD subjects, 20 subjects with MDD, and 94 healthy controls were examined using either of two identical MRI scanners and acquisition protocols. Diagnoses were based on DSM-IV criteria and confirmed one year after brain scanning. Image processing was conducted using voxel-based morphometry. RESULTS The BD group showed increased volume of the right dorsal anterior cingulate cortex relative to controls, while the MDD subjects exhibited bilateral foci GM deficits in the dorsolateral prefrontal cortex (p < 0.05, corrected for multiple comparisons). Direct comparison between BD and MDD patients showed a focus of GM reduction in the right-sided dorsolateral prefrontal cortex (p < 0.05, corrected for multiple comparisons) and a trend (p < 0.10, corrected) toward left-sided GM deficits in the dorsolateral prefrontal cortex of MDD patients. When analyses were repeated with scanner site as a confounding covariate the finding of increased right anterior cingulate volumes in BD patients relative to controls remained statistically significant (p=0.01, corrected for multiple comparisons). CONCLUSIONS These findings reinforce the view that there are important pathophysiological distinctions between BD and MDD, and indicate that subtle dorsal anterior cingulate abnormalities may be relevant to the pathophysiology of BD.

Cannabis use, cognition and brain structure in first-episode psychosis.

Cannabis use is highly prevalent worldwide and it is associated with psychosis, but its effects on brain structure and cognition are still controversial. The aim of this paper is to investigate cognitive functioning and brain structure in patients with their first episode of psychosis who used Cannabis. We examined gray matter and lateral ventricle volumes in 28 patients with first-episode psychosis and a history of Cannabis use, 78 patients without a history of Cannabis use and 80 healthy controls who had not used Cannabis. Cognition was assessed using forward and backwards digit span tests, from the Wechsler Memory Scale-Third Edition (WMS-III) and the Controlled Oral Word Association Test (COWAT). Patients with a history of Cannabis use had less brain abnormalities, characterized by gray matter and lateral ventricle volume preservation, as well as less attentional and executive impairments compared to patients without a history of Cannabis use. Cannabis-using patients who develop psychosis have less neurodevelopmental impairment and better cognitive reserve than other psychotic patients; perhaps reflecting different etiological processes.

Blood tranfusion in critically ill patients: state of the art.

Anemia is one of the most common abnormal findings in critically ill patients, and many of these patients will receive a blood transfusion during their intensive care unit stay. However, the determinants of exactly which patients do receive transfusions remains to be defined and have been the subject of considerable debate in recent years. Concerns and doubts have emerged regarding the benefits and safety of blood transfusion, in part due to the lack of evidence of better outcomes resulting from randomized studies and in part related to the observations that transfusion may increase the risk of infection. As a result of these concerns and of several studies suggesting better or similar outcomes with a lower transfusion trigger, there has been a general tendency to decrease the transfusion threshold from the classic 10 g/dL to lower values. In this review, we focus on some of the key studies providing insight into current transfusion practices and fueling the current debate on the ideal transfusion trigger.

Crianças com dificuldade de aprendizagem: um estudo de seguimento

Considering that learning problems are a vulnerability factor throughout child development, mainly when other adversities are present, this research investigated the association between past conditions and present adjustment in adolescents who have attended a child guidance clinic because of their learning difficulties. The adolescents and their mothers were interviewed and data related to past life conditions were taken from their files. We assessed 41 adolescents of both sexes, with an age mean of 13,8 years. Of those, two groups were constituted. The first had nine adolescents referred to mental health services because of severe adjustment problems. The second, ten adolescents with minimal adjustment difficulties. The comparison between groups showed more personal and familiar negative past conditions among adolescents with poorer present adjustment. These results point to the need for psychological follow-up of children presenting learning problems associated with other vulnerability conditions.

Corpus callosum volumes in recent-onset schizophrenia are correlated to positive symptom severity after 1 year of follow-up

Predicting the prognosis of schizophrenia is of critical importance but there are no valid biomarkers for such purpose. In case–control studies of schizophrenia using magnetic resonance imaging (MRI), the corpus callosum (CC) consistently displays alterations in morphology (Downhill et al., 2000; John et al., 2008), microstructural integrity (Mitelman et al., 2007; Whitford et al., 2010) and functioning (Chaim et al., 2010). In a previous voxel-basedmorphometry (VBM) study comparing recent-onset psychosis (ROP) patients to healthy controls, we reported CC volume reductions in schizophrenia spectrum subjects (Chaim et al, 2010). Herein, we investigated correlations between baseline CC volumes and the clinical prognosis of patients in regard to their symptom severity after 1 year. The patient samplewasdrawn fromapreviously described ROPpool (n=122) (Chaim et al., 2010).We included herein only thosewith confirmed DSM-IV schizophrenia (n=62) or schizoaffective disorder (n=07) (see demographic/clinical data in Table 1). Outcomemeasures were obtained using the Positive andNegative Syndrome Scale (PANSS) 1 year after initial identification of patients. MRI datasets were acquired

Mapping brain volumetric abnormalities in never-treated pathological gamblers

Several magnetic resonance imaging (MRI) studies to date have investigated brain abnormalities in association with the diagnosis of pathological gambling (PG), but very few of these have specifically searched for brain volume differences between PG patients and healthy volunteers (HV). To investigate brain volume differences between PG patients and HV, 30 male never-treated PG patients (DSM-IV-TR criteria) and 30 closely matched HV without history of psychiatric disorders in the past 2 years underwent structural magnetic resonance imaging with a 1.5-T instrument. Using Freesurfer software, we performed an exploratory whole-brain voxelwise volume comparison between the PG group and the HV group, with false-discovery rate correction for multiple comparisons (p < 0.05). Using a more flexible statistical threshold (p < 0.01, uncorrected for multiple comparisons), we also measured absolute and regional volumes of several brain structures separately. The voxelwise analysis showed no clusters of significant regional differences between the PG and HV groups. The additional analyses of absolute and regional brain volumes showed increased absolute global gray matter volumes in PG patients relative to the HV group, as well as relatively decreased volumes specifically in the left putamen, right thalamus and right hippocampus (corrected for total gray matter). Our findings indicate that structural brain abnormalities may contribute to the functional changes associated with the symptoms of PG, and they highlight the relevance of the brain reward system to the pathophysiology of this disorder.

Corrigendum to “Cannabis use, cognition and brain structure in first-episode psychosis” [Schizophr. Res., 147 (2013), 209–215]

a Laboratory of Psychiatric Neuroimaging (LIM-21), Department of Psychiatry, Faculty ofMedicine, University of Sao Paulo (USP), Rua Dr Ovidio Pires de Campos, s/n, 05403-010 Sao Paulo, SP, Brazil b Center for Interdisciplinary Research on Applied Neurosciences (NAPNA), USP, Rua Dr Ovidio Pires de Campos, s/n, 05403-010 Sao Paulo, SP, Brazil c Interdisciplinary Group of Studies on Alcohol and Drugs (GREA) and Equilibrium Program, Department of Psychiatry, Faculty of Medicine, USP, Rua Dr Ovidio Pires de Campos, s/n, 05403-010 Sao Paulo, SP, Brazil d LIM-23, Institute of Psychiatry, Clinics Hospital, Faculty of Medicine, USP, Rua Dr Ovidio Pires de Campos, s/n, 05403-010 Sao Paulo, SP, Brazil e Department of Preventive Medicine, Faculty of Medicine, USP, Av. Dr. Arnaldo, 455, 2° andar, Cerqueira Cesar, 01246-903 Sao Paulo, SP, Brazil f CEAPPesq, Institute of Mathematic and Statistics (IME), Department of Psychiatry, USP, Rua do Matao, 1010 — Cidade Universitaria, 05508-090 Sao Paulo, SP, Brazil g Department of Psychosis Studies, Institute of Psychiatry, Kings College, De Crespigny Park, London SE5 8AF, UK h Department of Neuroscience and Behaviour, Faculty of Medicine, USP, Av. Bandeirantes, 3900, Monte Alegre, 14048-900 Ribeirao Preto, SP, Brazil

Frontal cortex and normal aging: A voxel-based morphometry MRI study of healthy individuals

for significance using a bootstrapping method (Preacher & Kelley, 2010) with 10000 iterations. Results: Both HC (P<0.005) and ERC (P<0.0001) were significantly related to DMN connectivity while controlling for age and total grey matter. HC (Figure 1A) and ERC (Figure 1B) show similar patters of relationship with the DMN at the map level. ERCmediates the relationship between HC and DMN connectivity as assessed by a bootstrapping method (mediation ratio1⁄40.42, indirect effect1⁄41.03*10 -4, confidence interval1⁄4[3.35*10 -5 to 1.83*10 -5], p<0.001). Amyloid burden did not modify this effect. Conclusions: First, we find that structural measures of the MTL affect DMN connectivity above and beyond the effects of nonspecific greymatter and age. Second,we find further evidence for a structural/functional pathway between hippocampus and the DMN that is mediated by entorhinal cortex. Longitudinal analyses will elucidate the order in which these regions are impacted during AD development.