Viral Myocarditis-Incidence, Diagnosis and Management.

Viral myocarditis has an incidence rate of 10 to 22 per 100,000 individuals. The presentation pattern of viral myocarditis can range from nonspecific symptoms of fatigue and shortness of breath to more aggressive symptoms that mimic acute coronary syndrome. After the initial acute phase presentation of viral myocarditis, the virus may be cleared, resulting in full clinical recovery; the viral infection may persist; or the viral infection may lead to a persistent autoimmune-mediated inflammatory process with continuing symptoms of heart failure. As a result of these 3 possibilities, the diagnosis, prognosis, and treatment of viral myocarditis can be extremely unpredictable and challenging for the clinician. Herein, the incidence, etiology, definition and classification, clinical manifestation, diagnosis, pathogenesis, prognosis, and treatment of viral myocarditis are reviewed, and how acute clinical care teams might differentiate between viral myocarditis and other acute cardiac conditions is discussed.

Preoperative Treatment of Obstructive Sleep Apnea With Positive Airway Pressure is Associated With Decreased Incidence of Atrial Fibrillation After Cardiac Surgery.

OBJECTIVE: Based on clinical studies in the nonsurgical population that positive airway pressure (PAP) therapy for patients with obstructive sleep apnea (OSA) provides benefits for those with atrial fibrillation, the authors tested the hypothesis that PAP in patients with OSA reduces the incidence of postoperative atrial fibrillation (POAF) after cardiac surgery. DESIGN: Retrospective analysis. SETTING: Single-center university hospital. PARTICIPANTS: The study comprised 192 patients in sinus rhythm preoperatively who were undergoing nontransplantation or ventricular assist device implantation cardiac surgery requiring cardiopulmonary bypass but not requiring systemic circulatory arrest, with documented PAP adherence from January 2008 to October 2015. INTERVENTIONS: Retrospective review of medical records. MEASUREMENTS AND MAIN RESULTS: POAF was defined as atrial fibrillation requiring therapeutic intervention. Of the 192 patients with OSA, 104 (54%) were documented to be PAP-adherent and 88 (46%) were reported to be PAP-nonadherent. Among PAP users, 49 (47%) developed POAF; among PAP nonusers, 59 (66%) developed POAF. The adjusted hazard ratio was 0.59 (95% confidence interval 0.40-0.86, p<0.01). No differences were observed in intensive care unit length of stay (4.0±3.4 days for PAP-adherent group v 5.0±6.2 days for PAP-nonadherent group; p = 0.22) or hospital length of stay (10.7±6.6 days for PAP-adherent group v 10.9±7.3 days for PAP nonadherent group; p = 0.56). A lower median postoperative creatinine rise was observed in PAP-adherent patients (18.2% [8.3%-37.5%) v 31.3% [13.3%-50%]; p< 0.01). CONCLUSION: Preoperative PAP use in patients with OSA was associated with a decreased rate of POAF after cardiac surgery.

The impact of blood pressure cuff location on the accuracy of noninvasive blood pressure measurements in obese patients: an observational study.

PURPOSE: Obesity presents many challenges to the anesthesiologist, including poorly fitting blood pressure (BP) cuffs due to the conical shape of the upper arm. The aim of this study was to determine the accuracy of noninvasive BP readings, obtained from a noninvasive BP cuff using various cuff locations and wrapping techniques, compared with invasive intra-arterial BP readings. METHODS: Thirty American Society of Anesthesiologists physical status I-III obese (body mass index > 30 kg·m(-2)) individuals undergoing non-cardiac surgery were enrolled in this observational study. Serial oscillometric noninvasive BP (NIBP) measurements were taken in the patients' forearm and upper arm with two different wrapping formations (one following the contour of the upper arm, the other keeping cuff edges parallel). These NIBP measurements were compared with invasive arterial blood pressure (ABP) measurements taken from the ipsilateral radial artery. The precision and bias of the NIBP and ABP measurements were determined using Bland-Altman analysis. Analysis of variance and Welch's t test were used to determine between-group differences in bias. RESULTS: There was poor agreement between the ABP measurements and all types of NIBP measurements. Each of our study participants had a least one NIBP parameter (mean arterial pressure, systolic BP, or diastolic BP) that was > 10 mmHg different than the corresponding ABP parameter. Upper arm BP measurements showed a statistically insignificant trend toward underestimating ABP. For all cuff positions and wrapping techniques, systolic BP offered the best agreement between NIBP and ABP measurements. CONCLUSIONS: All the forms of NIBP cuff orientation studied had unacceptable precision and bias compared with invasive ABP measurements. When patient and/or surgical conditions necessitate accurate BP monitoring, direct arterial measurement should be considered over NIBP measurements in obese patients.

Intravaginal cytomegalovirus (CMV) challenge elicits maternal viremia and results in congenital transmission in a guinea pig model.

BACKGROUND: The objective of this study was to compare intravaginal (ivg) and subcutaneous (sc) administration of the guinea pig cytomegalovirus (GPCMV) in pregnant and non-pregnant guinea pigs. These studies tested the hypotheses that ivg infection would elicit immune responses, produce maternal viremia, and lead to vertical transmission, with an efficiency similar to the traditionally employed sc route. RESULTS: Four groups of age- and size-matched guinea pigs were studied. Two groups were pregnant, and two groups were not pregnant. Animals received 5 x 10(5) plaque-forming units (PFU) of a GPCMV reconstituted from an infectious bacterial artificial chromosome (BAC) construct containing the full-length GPCMV genome. Seroconversion was compared by IgG ELISA, and viremia (DNAemia) was monitored by PCR. In both pregnant and non-pregnant animals, sc inoculation resulted in significantly higher serum ELISA titers than ivg inoculation at 8 and 12 weeks post-infection. Patterns of viremia (DNAemia) were similar in animals inoculated by either sc or ivg route. However, in pregnant guinea pigs, animals inoculated by both routes experienced an earlier onset of DNAemia than did non-pregnant animals. Neither the percentage of dead pups nor the percentage of GPCMV positive placentas differed by inoculation route. CONCLUSIONS: In the guinea pig model of congenital CMV infection, the ivg route is as efficient at causing congenital infection as the conventional but non-physiologic sc route. This finding could facilitate future experimental evaluation of vaccines and antiviral interventions in this highly relevant animal model.

Routine postoperative care of patients undergoing coronary artery bypass grafting on cardiopulmonary bypass.

The postoperative course of a patient undergoing cardiac surgery (CS) is dictated by a largely predictable set of interactions between disease-specific and therapeutic factors. ICU personnel need to quickly develop a detailed understanding of the patient's current status and how critical care resources can be used to promote further recovery and eventual independence from external support. The goal of this article is to describe a typical operative and postoperative course, with emphasis on the latter, and the diagnostic and therapeutic options necessary for the proper care of these patients. This paper will focus on coronary artery bypass grafting as a model for understanding the course of CS patients; however, many of the principles discussed are applicable to most cardiac surgery patients.

Safer tracheostomy: a proposal for the routine use of an airway exchange catheter during tracheostomy.

In the United States, more than 100,000 tracheostomies are performed annually. Many patients undergoing tracheostomy are critically ill, making them higher risk surgical candidates. Fortunately, the loss of airway during the procedure is rare, but when it occurs, the outcome can be catastrophic. In this report, we describe a technique to minimize the risk of airway loss by using an airway exchange catheter as an airway conduit during endotracheal tube removal. We present 2 clinical cases in which this technique was used successfully and made an important contribution to patient safety.