Sara Shahrestani

The Impact of a Single Administration of Intranasal Oxytocin on the Recognition of Basic Emotions in Humans: A Meta-Analysis

Many studies have highlighted the potential of oxytocin (OT) to enhance facial affect recognition in healthy humans. However, inconsistencies have emerged with regard to the influence of OT on the recognition of specific emotional expressions (happy, angry, fear, surprise, disgust, and sadness). In this study, we conducted a meta-analysis of seven studies comprising 381 research participants (71 females) examining responses to the basic emotion types to assess whether OT enhances the recognition of emotion from human faces and whether this was influenced by the emotion expression and exposure time of the face. Results showed that intranasal OT administration enhances emotion recognition of faces overall, with a Hedges g effect size of 0.29. When analysis was restricted to facial expression types, significant effects of OT on recognition accuracy were specifically found for the recognition of happy and fear faces. We also found that effect sizes increased to moderate when exposure time of the photograph was restricted to early phase recognition (<300 ms) for happy and angry faces, or later phase recognition for fear faces (>300 ms). The results of the meta-analysis further suggest that OT has potential as a treatment to improve the recognition of emotion in faces, allowing individuals to improve their insight into the intentions, desires, and mental states of others.

A single dose of oxytocin nasal spray improves higher-order social cognition in schizophrenia

Schizophrenia is associated with significant impairments in both higher and lower order social cognitive performance and these impairments contribute to poor social functioning. People with schizophrenia report poor social functioning to be one of their greatest unmet treatment needs. Recent studies have suggested the potential of oxytocin as such a treatment, but mixed results render it uncertain what aspects of social cognition are improved by oxytocin and, subsequently, how oxytocin might best be applied as a therapeutic. The aim of this study was to determine whether a single dose of oxytocin improved higher-order and lower-order social cognition performance for patients with schizophrenia across a well-established battery of social cognition tests. Twenty-one male patients received both a single dose of oxytocin nasal spray (24IU) and a placebo, two weeks apart in a randomized within-subjects placebo controlled design. Following each administration, participants completed the social cognition tasks, as well as a test of general neurocognition. Results revealed that oxytocin particularly enhanced performance on higher order social cognition tasks, with no effects on general neurocognition. Results for individual tasks showed most improvement on tests measuring appreciation of indirect hints and recognition of social faux pas. These results suggest that oxytocin, if combined to enhance social cognition learning, may be beneficial when targeted at higher order social cognition domains. This study also suggests that these higher order tasks, which assess social cognitive processing in a social communication context, may provide useful markers of response to oxytocin in schizophrenia.

Heart rate variability during adolescent and adult social interactions: a meta-analysis.

Social interaction skill is important for psychological wellbeing, stress regulation, protection from disability and overall life satisfaction. Increase in activity of the vagus nerve, measured by heart rate variability (HRV), is associated with social interaction skill and decreased stress. In this meta-analysis we collated statistics from thirteen studies consisting of 787 participants who were participating in social interactions while HRV was simultaneously collected. Results revealed that while dyadic social interactions do not increase HRV generally from a baseline state, negative dyadic social interactions decrease HRV in a manner similar to the Trier Social Stress Task. Further, participants with psychopathology do not show cardiac autonomic flexibility during social interactions as indicated by reductions under stress and increases with subsequently positive social interactions. The role of age, gender and HRV index were also examined as potential moderators of HRV. Implications for health and wellbeing resulting from exposure to negative social interactions are discussed.

Heart Rate Variability during Social Interactions in Children with and without Psychopathology: A Meta-Analysis.

BACKGROUND The inability to regulate autonomic activity during social interactions is believed to contribute to social and emotional dysregulation in children. Research has employed heart rate variability (HRV) during both socially engaging and socially disengaging dyadic tasks between children and adults to assess this. METHODS We conducted a meta-analysis including evidence from 18 studies comprising 1,544 children who were categorized as either healthy or at risk/diagnosed with psychopathology. Within these groups, we assessed the impact of social engagement and disengagement tasks on HRV. RESULTS Results showed that social engagement tasks left HRV unaltered to a baseline. Social disengagement, however, was associated with decreases in HRV. In a task that included disengagement and then engagement, HRV was reduced during disengagement but was then restored during the reunion phase (engagement). Children at risk or with a diagnosis for psychopathology, however, failed to show any change in HRV during dyadic social interaction tasks. This was despite a social stressor, the Trier Social Stress Test, causing significantly reduced HRV in both groups. CONCLUSIONS This meta-analysis provides support to suggest HRV may provide a worthwhile context specific marker for the effective regulation of dyadic social interactions in children.

Outcomes From Pancreatic Transplantation in Donation After Cardiac Death: A Systematic Review and Meta-analysis

Background Pancreas transplantation remains the gold standard for treatment for type I diabetes providing an insulin-independent, normoglycemic state. Increasingly, donation after cardiac death (DCD) donors are used in view of the organ donor shortage. We aimed to systematically review recipient outcomes from DCD donors and where possible compared these with donor after brain death (DBD) donors. Methods We searched the databases MEDLINE via PubMed, EMBASE, and The Cochrane Library from inception to March 2015, for studies reporting the outcome of DCD pancreas transplants. We appraised studies using the Newcastle-Ottawa scale and meta-analyzed using a random effects model. Results We identified 18 studies, 4 retrospective and 6 prospective cohort studies and 8 case reports. Our bias assessment revealed that although studies were well conducted, some studies had potential confounding factors and absence of comparator groups. Eight of the 18 studies included a DBD comparison group comprising 23 609 transplant recipients. Importantly, there was no significant difference in allograft survival up to 10 years (hazard ratio, 0.98; 95% confidence interval [95% CI], 0.74-1.31; P = 0.92), or patient survival (hazard ratio, 1.31; 95% CI, 0.62-2.78; P = 0.47) between DCD and DBD pancreas transplants. We estimated that the odds of graft thrombosis was 1.67 times higher in DCD organs (95% CI, 1.04-2.67; P = 0.006). However, subgroup analysis found thrombosis was not higher in recipients whose DCD donors were given antemortem heparin (P = 0.62). Conclusions Using current DCD criteria, pancreas transplantation is a viable alternative to DBD transplantation, and antemortem interventions including heparinization may be beneficial. This potential benefit of DCD pancreas donation warrants further study.

Donation After Circulatory Death for Liver Transplantation: A Meta-Analysis on the Location of Life Support Withdrawal Affecting Outcomes.

Background Liver transplantation using donation after circulatory death (DCD) donors is associated with inferior outcomes compared to donation after brain death (DBD). Prolonged donor warm ischemic time has been identified as the key factor responsible for this difference. Various aspects of the donor life support withdrawal procedure, including location of withdrawal and administration of antemortem heparin, are thought to play important roles in mitigating the effects of warm ischemia. However, a systematic exploration of these factors is important for more confident integration of these practices into a standard DCD protocol. Methods Medline, EMBASE, and Cochrane libraries were systematically searched and 23 relevant studies identified for analysis. Donation after circulatory death recipients were stratified according to location of life support withdrawal (intensive care unit or operating theater) and use of antemortem heparin. Results Donation after circulatory death recipients had comparable 1-year patient survival to DBD recipients if the location of withdrawal of life support was the operating theater, but not if the location was the intensive care unit. Likewise, the inferior 1-year graft survival and higher incidence of ischemic cholangiopathy of DCD compared with DBD recipients were improved by withdrawal in operating theater, although higher rates of ischemic cholangiopathy and worse graft survival were still observed in DCD recipients. Furthermore, administering heparin before withdrawal of life support reduced the incidence of primary nonfunction of the allograft. Conclusions Our evidence suggests that withdrawal in the operating theater and premortem heparin administration improve DCD liver transplant outcomes, thus allowing for the most effective usage of these valuable organs.

Dual kidney transplant techniques: A systematic review

Dual kidney transplantation (DKT) was developed to improve outcomes from transplantation of extended criteria donors (ECD). This study examined which surgical techniques have been reported for DKT and whether any technique had superior patient and graft survival.

Clinicians’ Attitudes and Perspectives on Ante-Mortem Interventions in Deceased Organ Donation: An International Interview Study

Introduction Deceased donation does not meet the current need for organ transplantation, and in some counties, medical interventions on patients before the declaration of death for organ donation is legal and performed. However, this practice involves ethical and legal challenges. The purpose of the present study was to describe the attitudes, perspectives and values of clinicians on the acceptability of ante-mortem interventions. Materials and Methods Thirty clinicians (ICU physicians, donor coordinators, transplant physicians, transplant surgeons and policy makers) from eight countries (Australia, New Zealand, United States, United Kingdom, Italy, Japan, Korea and Vietnam) participated in semi-structured interviews on ante-mortem interventions including heparinization, femoral cannulation, donor cooling, ECMO and location of withdrawal. We used thematic analysis to analyse the data. Results Four major themes were identified: the death experience (protection of donor dignity as paramount, reduction of family distress in the context of donation, fear regarding influencing the process and speed of dying), respect for autonomy (supporting the individual desire to donate when it conflicts with family or clinician views, family choice in how donation proceeds, clinician roles in practicing beneficence and non-maleficence in the context of donation done for the benefit of a third party), education and understanding about the practices of organ donation (concern about misunderstandings and distrust in organ donation, clinician and family tensions in accepting brain death or cardiac death, ramifications of miscommunication with families for organ donation in general) and desire for optimising evidence based practice (desire for clear evidence of efficacy to discuss with families, desire for evidence of lack of harm prior to implementation). Conclusions Clinicians involved in organ donation and transplantation believe that ante-mortem interventions are only appropriate in instances where the distress of the death experience for the family and donor are not increased. Both the family and donor must have a strong drive to successful donation, and research must show that interventions are beneficial and do not cause harm to donors. As donation after circulatory death increases in prevalence, international discussion among policymakers will need to take place to determine the role of these practices.

Optimal surgical management in kidney and pancreas transplantation to minimise wound complications: A systematic review and meta-analysis

Background Immunosuppression in transplant patients increases the risk of wound complications. However, an optimal surgical approach to kidney and pancreas transplantation can minimise this risk. Materials and methods We performed a systematic review and meta-analysis to examine factors contributing to incisional hernia formation in kidney and pancreas transplant recipients. Bias appraisal of studies was conducted via the Newcastle-Ottawa scale. We considered recipient factors, surgical methods, and complications of repair. Results The rate of incisional hernia formation in recipients of kidney and pancreas transplants was 4.4% (CI 95% 2.6–7.3, p < 0.001). Age above or below 50 years did not predict hernia formation (Q (1) = 0.09, p = 0.77). Body mass index (BMI) above 25 (10.8%, CI 95% 3.2–30.9, p < 0.001) increased the risk of an incisional hernia. Mycophenolate mofetil (MMF) use significantly reduced the risk of incisional hernia from 11.9% (CI 95% 4.3–28.7, p < 0.001) to 3.8% (CI 95% 2.5–5.7, p < 0.001), Q (1) = 4.25, p = 0.04. Sirolimus significantly increased the rate of incisional hernia formation from 3.7% (CI 95% 1.7–7.1, p < 0.001) to 18.1% (CI 95% 11.7–27, p < 0.001), Q (1) = 13.97, p < 0.001. While paramedian (4.1% CI 95% 1.7–9.4, p < 0.001) and Rutherford-Morrison incisions (5.6% CI 95% 2.5–11.7, p < 0.001) were associated with a lower rate of hernia compared to hockey-stick incisions (8.5% CI 95% 3.1–21.2, p < 0.001) these differences were not statistically significant (Q (1) = 1.38, p = 0.71). Single layered closure (8.1% CI 95% 4.9–12.8, p < 0.001) compared to fascial closure (6.1% CI 95% 3.4–10.6, p < 0.001) did not determine the rate of hernia formation [Q (1) = 0.55, p = 0.46]. Conclusions Weight reduction and careful immunosuppression selection can reduce the risk of a hernia. Rutherford-Morrison incisions along with single-layered closure represent a safe and effective technique reducing operating time and costs.

Contamination of Organ Donor Transport Media With Enteric Flora Predicts Clinically Significant Transplant Site Infections

Introduction The routine culture of organ donor transport media (ODTM) is yet to become standard policy at all transplant centers. This is possibly due to most previous studies finding it is characterized by low culture rates and unclear clinical utility. Our aim was to review our data from bacterial cultures of all ODTM to identify key factors that may contribute to potential infections in transplant recipients. Methods We reviewed 457 recipients of kidney, pancreas or SPK transplants, of which 286 had cultures performed on ODTM, using sterile technique. 208 samples were transferred into standard culture pots and 95 into BACTEC culture pots. Culture results were reviewed and organisms classified by likely source (skin flora, enteric flora or respiratory/oral flora). We then reviewed the presence of any clinically significant infection at the transplant site in all recipients and characterized the organisms by likely source. Analysis with SPSS statistical package was performed to assess the rate of contamination by source for kidney or SPK transplants and ascertain the likelihood of correspondence in infection source. Results The sensitivity of BACTEC culture was significantly superior to standard culture (X2(1, 286) =74.06, p<0.001), detecting contamination in 62.1% of samples. This was relative to 15.9% of samples in the standard culture. The increased rate of contamination in the kidney for SPK group over the kidney for kidney alone group was driven by the high rate of enteric flora contamination in the SPK group (26.5%, N=9/34), over kidney for kidney alone transplant (9.8%, N=6/61). This is particularly relevant given 38.5% (10/26) of recipients with enteric flora contamination of transport media had an infection of the transplant site caused by enteric flora. Only 25% (65/260) of recipients who did not have contamination with enteric flora had an infection of the transplant site caused by enteric flora. Conclusions BACTEC culture is significantly superior and should be adopted as the standard of culture at all transplant centers, to improve the utility of routine testing of ODTM. Evidence suggests transmissibility of enteric contamination of ODTM, and the SPK transplant group is particularly vulnerable in this regard.