Lindell K. Weaver

Quality of life, emotional, and cognitive function following acute respiratory distress syndrome.

Acute Respiratory Distress Syndrome (ARDS) is characterized by lung injury and hypoxemia, has a high mortality rate, and is associated with significant morbidity including cognitive and emotional sequelae and decreased quality of life. There is limited information regarding which of these factors are associated with decreased quality of life. This study assessed the relationships between quality of life, cognitive and emotional function in ARDS survivors at 1-year post-hospital discharge. Sixty-six ARDS survivors were administered a battery of neuropsychological tests, measures of emotional function and quality of life 1 year post-hospital discharge. At 1 year 45% of the ARDS patients had cognitive sequelae and 29% had mild to moderate symptoms of depression and anxiety. Depression, anxiety, and intensive care unit length of stay were significantly correlated with decreased quality of life. Cognitive impairments did not correlate with decreased quality of life. Illness severity and emotional function, but not cognitive sequelae, are associated with decreased quality of life 1 year following ARDS. ARDS is common and may result in significant cognitive and emotional morbidity and decreased quality of life.

Severe anoxia with and without concomitant brain atrophy and neuropsychological impairments.

Significant anoxia may cause a variety of neuropathologic changes as well as cognitive deficits. We have recently seen 3 patients who have suffered severe anoxic episodes all with initial Glasgow Coma Scores (GCS) of 3 with sustained coma for 10-14 d. All 3 patients had extended hospitalizations and rehabilitation therapy. A neuropsychological test battery was administered and volumetric analyses of MRI scans were carried out in each case at least 6 mo postinjury. Two of the patients display distinct residual cognitive and neuropathologic changes while 1 patient made a remarkable recovery without evidence of significant morphological abnormality. These three cases demonstrate, that even with similar admission GCS, the outcome is variable and the degree of neuropsychological impairment appears to match the degree of morphologic abnormalities demonstrated by quantitative MR image analysis. An important finding of this study is that even though subjects with an anoxic insult exhibit severe cognitive and memory impairments along with concomitant morphologic changes, their attention/concentration abilities appear to be preserved. MR morphometry provides an excellent means by which neural structural changes can be quantified and compared to neuropsychological and behavioral outcomes.

Cognitive sequelae in acute respiratory distress syndrome patients with and without recall of the intensive care unit

Some critically ill patients have dramatic recollections of the intensive care unit (ICU), whereas 23-50% have little or no recollection of their ICU stay. In addition, cognitive impairments are common following critical illness and ICU treatment. Little is known regarding the relationship between cognitive sequelae and ICU recall. We assessed recall of the ICU and its relationship to cognitive functioning at hospital discharge and 1 and 2 years after discharge in 70 consecutive acute respiratory distress syndrome (ARDS) patients. Seventeen patients (24%) had no recall of the ICU. Patients without ICU recall had increased rates of cognitive sequelae at hospital discharge and 1-year follow-up compared with the ICU recall group. Patients without ICU recall had a greater magnitude of cognitive impairments at hospital discharge, but not at 1- or 2-year follow-up. Profile analysis showed significant group differences in general intellectual functioning, executive function, processing speed, and spatial skills at hospital discharge, but not at 1- or 2-year follow-up. Estimated premorbid intelligence scores were inversely related to the magnitude of cognitive sequelae, suggesting greater cognitive reserve in patients with fewer cognitive decrements.

Neuropsychological impairments following hantavirus pulmonary syndrome

Recently an outbreak of acute respiratory infection associated with the hantavirus occurred in the southwestern United States. Hantavirus pulmonary syndrome (HPS) is a life threatening illness that carries with it a high mortality rate. Patients with HPS experience prolonged periods of hypoxemia requiring mechanical ventilation and treatment in intensive care units. We have recently seen 2 survivors of HPS. A neuropsychological test battery was administered immediately following their acute hospitalization and at 1 year postrecovery from HPS. Both patients exhibited cognitive impairments immediately following HPS as well as persistent cognitive impairments at 1 year. The cognitive impairments seen in these two HPS survivors are similar to those seen in other patients who have experienced brain anoxia, including memory impairments. It is also possible that hantavirus may directly cause brain injury with concomitant cognitive impairments. Additional research needs to be carried out in order to determine the extent and severity of the cognitive impairments in survivors of HPS.

Three Dimensional Image Reconstruction of Neuroanatomical Structures: Methods for Isolation of the Cortex, Ventricular System, Hippocampus, and Fornix

Magnetic Resonance (MR) imaging allows volumetric quantification of a variety of neuroanatomical structures using two dimensional (2D) images as well as three-dimensional (3D) reconstruction of the brain and any of its constituent parts. Three-dimensional analysis permits integration of the neuroanatomical changes which occur in pathologic states, with the cognitive and behavioral changes elucidated through neuropsychological assessment. This paper describes uniform methods for 3D neuroanatomical isolation of the neocortex, ventricular system, and hippocampus in both normal and pathologic states. The 3D methods are described in detail using two different software programs, ANALYZE and IMAGE. Three-dimensional neuroanatomical reconstructions were carried out on a patient who sustained a very severe traumatic brain injury. The 3D image analysis in the patient with traumatic brain injury, revealed structural changes in frontal and temporal cortex, ventricular dilation, and hippocampal atropy. The neuropsychological impairments in this patient, were consistent with the observed neuroanatomical changes revealed on 3D image reconstruction. This technology permits precise determinations of the extent and severity of the neuroanatomical changes which follow neurological injury disease.

Decreases in white matter integrity of ventrolimbic pathway linked to posttraumatic stress disorder in mild traumatic brain injury

Post-traumatic stress disorder (PTSD) is commonly observed in military service members with mild traumatic brain injury (mTBI); however, the relationship between mTBI and PTSD is complex and not well understood. The present study aims to elucidate a link between the degree of alteration in limbic system-related white matter tracts and PTSD symptoms in an mTBI population. Diffusion-tensor imaging (DTI) with probabilistic tractography of the fronto-limbic pathways revealed decreased white matter integrity in the uncinate fasciculus in those with co-morbid mTBI and PTSD (nu2009=u200934), relative to those with only mTBI (nu2009=u200935). Additionally, fractional anisotropy (FA) and radial diffusivity (RD) measures in the bilateral uncinate fasciculus correlated with Post-Traumatic Stress Disorder Checklist Civilian version (PCL-C) scores, and primarily within the avoidance and re-experiencing domains. Findings from this study suggest the degree of traumatic injury within the limbic system could be directly related to post-traumatic stress and post-concussive symptoms, with disrupted white matter leading to significant PTSD outcomes.