Gilbert Seda

Immune regulation of procalcitonin: a biomarker and mediator of infection.

Procalcitonin (PCT) has recently emerged as a powerful biomarker for an early and accurate diagnosis of bacterial infection. Here we summarize our current understanding of the expression pathways of PCT, its potential cellular sources including immune cells, and factors inducing its secretion. Also addressed is the significance of increased blood PCT concentration, which may allow this molecule not only to act as a clinical biomarker but also as an active participant in the development and progression of infectious processes. Experimental approaches to delineate a better understanding of PCT functions, molecular pathways that modulate its expression and therapeutic opportunities to curtail its biological actions are discussed, as well.

Medication Effects on Sleep and Breathing

Sleep respiration is regulated by circadian, endocrine, mechanical and chemical factors, and characterized by diminished ventilatory drive and changes in Pao2 and Paco2 thresholds. Hypoxemia and hypercapnia are more pronounced during rapid eye movement. Breathing is influenced by sleep stage and airway muscle tone. Patient factors include medical comorbidities and body habitus. Medications partially improve obstructive sleep apnea and stabilize periodic breathing at altitude. Potential adverse consequences of medications include precipitation or worsening of disorders. Risk factors for adverse medication effects include aging, medical disorders, and use of multiple medications that affect respiration.

Comparative meta-analysis of prazosin and imagery rehearsal therapy for nightmare frequency, sleep quality, and posttraumatic stress.

STUDY OBJECTIVE In this meta-analysis, we compare the short-term efficacy of prazosin vs. IRT on nightmares, sleep quality, and posttraumatic stress symptoms (PTSS). METHODS Reference databases were searched for randomized controlled trials using IRT or prazosin for nightmares, sleep disturbance, and/or PTSS. Effect sizes were calculated by subtracting the mean posttest score in the control group from the mean posttest score in the treatment group, and dividing the result by the pooled standard deviation of both groups. Mixed effects models were performed to evaluate effects of treatment characteristics, as well as sample characteristics (veteran vs. civilian) on treatment efficacy. RESULTS Four studies used prazosin, 10 used IRT alone or in combination with another psychological treatment, and 1 included a group receiving prazosin and another group receiving IRT. Overall effect sizes of both treatments were of moderate magnitude for nightmare frequency, sleep quality, and PTSS (p < 0.01). Effect size was not significantly different with type of treatment (psychological vs. pharmacological) on nightmare frequency (p = 0.79), sleep quality (p = 0.65), or PTSS, (p = 0.52). IRT combined with CBT for insomnia showed more improvement in sleep quality compared to prazosin (p = 0.03), IRT alone (p = 0.03), or IRT combined with another psychological intervention, (p < 0.01). CONCLUSION Although IRT interventions and prazosin yield comparable acute effects for the treatment of nightmares, adding CBT for insomnia to IRT seems to enhance treatment outcomes pertaining to sleep quality and PTSS. More randomized clinical trials with long-term follow-up are warranted. COMMENTARY A commentary on this article appears in this issue on page 9.

Plasmapheresis in the Management of Severe Hypertriglyceridemia

Plasmapheresis can benefit a variety of critically ill patients. A woman with diabetic ketoacidosis and severe hypertriglyceridemia was treated with plasmapheresis when conventional treatments did not markedly reduce her triglyceridemia. The patient was admitted to a medical intensive care unit because of diabetic ketoacidosis with severe lipemia. The lipemia-associated interference in laboratory studies made treatment of electrolyte abnormalities extremely difficult. The hypertriglyceridemia was initially treated with insulin, antilipidemic medications, and heparin, but the levels of triglycerides remained elevated, delaying results of needed laboratory studies for hours. After plasmapheresis, the serum level of triglycerides decreased by 77% in less than 24 hours. Severe lipemia interferes with photometric laboratory studies, yielding an underestimation of serum levels of electrolytes. Plasmapheresis is safe, rapid, and effective for emergent management of severe hypertriglyceridemia in critically ill patients. The impact of the procedure on critical care nursing is growing as nurses become involved in the treatment and follow-up care of patients who have plasmapheresis.

Predominant Cartilaginous Hamartoma: An Unusual Variant of Chondromatous Hamartoma

Chondromatous hamartomas are the most common benign lung tumors and the third most common pulmonary nodule. Histologically, they are characteristically composed of hyaline cartilage mixed with fibromyxoid stroma and adipose tissue surrounded by epithelial cells. We report the case of a healthy, 60-year-old woman with an incidentally discovered chondromatous hamartoma that was thorascopically excised. Her pulmonary hamartoma was predominantly cartilaginous, which only occurs in 1% of hamartomas.

Chronic Obstructive Pulmonary Disease and Vascular Disease Delay Timeliness of Early Stage Lung Cancer Resectional Surgery

Abstract Introduction: Lung cancer remains the leading cause of cancer death in the United States and worldwide. Timeliness to diagnosis and referral for resectional surgey is key to successful management for early stage disease. Methods: We investigated the contribution of medical co-morbidities in the timeliness to resectional surgery for non-small cell lung cancer (NSCLC). A retrospective record review of NSCLC surgery cases at Naval Medical Center San Diego (NMCSD) from 2004 to 2009 from the tumor registry was conducted. Results: More than 75% of NSCLC patients exhibited at least one co-morbidity. Of the 84 patients, 26% of patients had diabetes, patients with different vascular co-morbidities accounted for 39%, whereas 33% of subjects had COPD. Patients with sleep apnea or liver disease each accounted for 6%. Vascular disease co-morbidity and COPD in NSCLC patients significantly delayed time from initial cardiothoracic surgery evaluation to thoracotomy (p = 0.01–0.02 and p < 0.05 respectively). Conclusion: Although significances of different co-morbities in the development NSCLC cannot be extrapolated, theses data show that COPD and vascular diseases are significant risk factors that delay surgical treatment of early stage lung cancer.