The Impact of Stress Hormones on Post-traumatic Stress Disorders Symptoms and Memory in Cardiac Surgery Patients

Patient periprocedural stress in cardiovascular medicine: friend or foe?

Stress, a disruption of homeostasis, is an unavoidable part of everyday life. In medical procedures, stress profoundly affects both operators and patients. Although the stress reaction has evolved to aid survival of physical trauma, it may also be harmful, by aggravating the baseline medical condition and/or creating new stress-related medical problems. Stress responses comprise several protective mechanisms that are particularly relevant in the clinical setting (e.g., a procoagulatory state and blood loss counteraction, preservation of blood perfusion pressure, prevention of hypoglycemia, enhanced immune response). Beneficial psychological effects prevent recurrence of traumatic memories, and promote patient compliance and positive lifestyle changes. In contrast, overt acute stress responses may lead to severe pathological conditions such as cytokine storm, post-traumatic stress disorder, takotsubo syndrome, deep venous thrombosis and pulmonary embolism, myocardial infarction, life-threatening arrhythmias and sudden cardiac death. There is also evidence that stress exposure may promote atherosclerosis and reduce long-term benefits from the intervention (increase in major adverse clinical events, in-stent restenosis, etc.). Insights into the role of stress on the operator’s performance have recently led to the introduction of counteractive measures such as simulation training. Conversely, very little is known about the effect of the patient’s periprocedural stress on the outcomes of cardiovascular procedures. Recent data show that the patient periprocedural stress affects the well-being of whole families. This review, focused on topics particularly relevant to cardiovascular interventions, provides a mechanistic insight into beneficial and harmful effects of periprocedural patient stress, including the array of available stress-relieving measures.

Epinephrine May Contribute to the Persistence of Traumatic Memories in a Post-traumatic Stress Disorder Animal Model

The importance of catecholamines in post-traumatic stress disorder (PTSD) still needs to be explored. We aimed to evaluate epinephrine’s (EPI) causal role and molecular mechanism for the persistence of PTSD traumatic memories. Wild-type (WT) and EPI-deficient mice (phenylethanolamine-N-methyltransferase-knockout mice, Pnmt-KO) were induced with PTSD and behavioral tests were performed. Some Pnmt-KO mice were administered with EPI or vehicle. Catecholamines were quantified by HPLC-ED. Nr4a1, Nr4a2, and Nr4a3 mRNA expression were evaluated by real-time PCR in hippocampus samples. It was observed an increase in EPI and freezing behavior, and a decrease in open arm entries in the elevated plus-maze test and time spent in the light in the light–dark test in WT mice in the PTSD-induction group compared to control. After induction of PTSD, Pnmt-KO mice showed a decrease in freezing, as well as an increase in open arm entries and transitions between compartments compared to WT. After PTSD induction, Pnmt-KO mice administered with EPI showed an increase in freezing compared with the vehicle. On day 0 of PTSD induction, it was observed an increase in mRNA expression of Nr4a2 and Nr4a3 genes in the hippocampus of WT mice compared to control, contrary to Pnmt-KO mice. In conclusion, our data suggest that EPI may be involved in the persistence of traumatic memories in PTSD, possibly through enhancement of the expression of Nr4a2 and Nr4a3 genes in the hippocampus. Peripheral administration of EPI restored contextual traumatic memories in Pnmt-KO mice, which suggests a causal role for EPI. The persistence of contextual traumatic memories may contribute to anxiety-like behavior and resistance of traumatic memory extinction in this PTSD mice model.

Long-term quality of life and posttraumatic stress following elective cardiac surgery: preliminary findings of a 5-year follow-up study

BACKGROUND

Heart surgery is a major stressful event that can have a significant negative effect on patients' quality of life (QoL) and may cause long-term posttraumatic stress reactions. The aim of this pilot study was to estimate the longitudinal change and predictors of health-related quality of life (HRQOL) dynamics and identify factors associated with PTS at 5-year follow-up (T2) after elective cardiac surgery and associations with pre-surgery (T1) QoL.

MATERIALS AND METHODS

Single-centre prospective study was conducted after Regional Bioethics Committee approval. Adult consecutive patients undergoing elective cardiac surgery were included. HRQOL was measured using the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) questionnaire before (T1) and 5-years after (T2) cardiac surgery. Posttraumatic stress was assessed using the International Trauma Questionnaire.

RESULTS

The pilot study revealed a significant positive change at 5-year follow-up in several domains of SF-36: physical functioning (PF), energy/fatigue (E/F), and social functioning (SF). Prolonged postoperative hospital stay was associated with change in SF (p < 0.01), E/F (p < 0.05) and emotional well-being (p < 0.05). The percentage of patients that had the posttraumatic stress disorder (PTSD) at T2 was 12.2%. Posttraumatic stress symptoms were associated with longer hospitalization after surgery (p < 0.01).

CONCLUSIONS

HRQOL improved from baseline to five years postoperatively. Patients with lower preoperative HRQOL scores tended to have a more significant improvement of HRQOL five years after surgery. A prolonged postoperative hospital stay had a negative impact on postoperative social functioning, energy/fatigue, and emotional well-being. Increased levels of PTSD were found in cardiac surgery patients following five years after the surgery.

Intraneuronal protein aggregation as a trigger for inflammation and neurodegeneration in the aging brain

Age is, by far, the greatest risk factor for Alzheimer's disease (AD), yet few AD drug candidates have been generated that target pathways specifically associated with the aging process itself. Two ubiquitous features of the aging brain are the intracellular accumulation of aggregated proteins and inflammation. As intraneuronal amyloid protein is detected before markers of inflammation, we argue that old, age-associated, aggregated proteins in neurons can induce inflammation, resulting in multiple forms of brain toxicities. The consequence is the increased risk of old, age-associated, neurodegenerative diseases. As most of these diseases are associated with the accumulation of aggregated proteins, it is possible that any therapeutic that reduces intracellular protein aggregation will benefit all.-Currais, A., Fischer, W., Maher, P., Schubert, D. Intraneuronal protein aggregation as a trigger for inflammation and neurodegeneration in the aging brain.

Impact of Sedation on Cognitive Function in Mechanically Ventilated Patients

The practice of sedation dosing strategy in mechanically ventilated patient has a profound effect on cognitive function. We conducted a comprehensive review of outcome of sedation on mental health function in critically ill patients on mechanical ventilation in the intensive care unit (ICU). We specifically evaluated current sedative dosing strategy and the development of delirium, post-traumatic stress disorders (PTSDs) and agitation. Based on this review, heavy dosing sedation strategy with benzodiazepines contributes to cognitive dysfunction. However, outcome for mental health dysfunction is mixed in regard to newer sedatives agents such as dexmedetomidine and propofol. Moreover, studies that examine the impact of sedatives for persistence of PTSD/delirium and its long-term cognitive and functional outcomes for post-ICU patients are frequently underpowered. Most studies suffer from low sample sizes and methodological variations. Therefore, larger randomized controlled trials are needed to properly assess the impact of sedation dosing strategy on cognitive function.

The Impact of High Versus Low Sedation Dosing Strategy on Cognitive Dysfunction in Survivors of Intensive Care Units: A Systematic Review and Meta-Analysis

BACKGROUND

The practice of low vs. high sedation dosing strategy may impact the cognitive and mental health function in the intensive care unit (ICU). We aim to demonstrate that high sedation strategy will result in change of mental health function in ICU patients.

METHODS

We performed a systemic search and meta-analysis of medical databases in MEDLINE (from 1966 to March 2013) and EMBASE (from 1980 to March 2013), as well as the Cochrane Library using the MESH terms "Intensive Care Unit," and "Mental Health, for assessing the impact of sedation on posttraumatic stress disorder (PTSD) or anxiety/depression and delirium in the mix ICU setting including cardiac surgery patients. A total of 1216 patients were included in the final analysis.

RESULTS

We included 11 studies in the final analysis and concluded that high dose sedation strategy resulted in higher incidence of cognitive dysfunction with P value of 0.009. The result for subgroup of delirium showed P = 0.11 and PTSD/depression or anxiety of P = 0.001, Heterogeneity I2 was 64%. Overall analysis was statistically significant with a P value of 0.002.

CONCLUSION

High sedation dosing strategy will negatively affect cognitive function in critically ill patients. Large randomized trials are needed to address cognitive dysfunction in subgroup of patients with delirium.