Brittany A. Zwischenberger

Meta-Analysis of the Correlation Between Chronic Cerebrospinal Venous Insufficiency and Multiple Sclerosis

Purpose: To determine whether a correlation exists between chronic cerebrospinal venous insufficiency (CCSVI) and multiple sclerosis (MS). Materials and Methods: A meta-analysis of the current literature was performed to evaluate the frequency of CCSVI, diagnosed by echo color Doppler criteria, in patients with MS and in normal controls. Results: In all, 19 studies were identified from January 2005 through February 2013; however, 3 studies were excluded due to duplicate data and 3 additional studies because 0 patients fulfilled CCSVI criteria in both MS and control groups. In order to improve homogeneity, 4 outlier studies were also removed from the analysis. Analysis of the remaining 9 studies demonstrated a significant correlation between CCSVI and MS (odds ratio 1.885, P < .0001) with no significant heterogeneity of the studies (I 2 = 18, P = .279). Conclusions: The meta-analysis demonstrated a correlation between CCSVI and MS. However, there was no evidence that CCSVI has a causative role in MS.

Increased coagulation and suppressed generation of activated protein C in aged mice during intra-abdominal sepsis.

Sepsis is a life-threatening clinical condition that is particularly serious among the elderly who experience considerably higher mortality rates compared with younger patients. Using a sterile endotoxemia model, we previously reported age-dependent mortality in conjunction with enhanced coagulation and insufficient levels of anti-coagulant factor activated protein C (aPC). The purpose of the present study was to further investigate the mechanisms for age-dependent coagulation and aPC insufficiency during experimental sepsis. Intra-abdominal sepsis was induced by cecal ligation and puncture (CLP) using 21 or 16 gauge (G) needles (double-puncture) on young (4 to 6 mo old) and aged (20 to 25 mo old) male C57BL/6 mice. When compared with young mice, aged mice showed significantly increased mortality (92% vs. 28%), systemic inflammation, and coagulation in the lung and kidney after 21G CLP. Young mice with more severe CLP (16G) showed a mortality rate and inflammation equivalent to aged mice with 21G CLP; however, enhanced coagulation and kidney dysfunction were significant only in the aged. In young mice, increased levels of aPC after CLP were coupled with reduced levels of protein C (PC), suggesting the conversion of PC to aPC; however, PC and aPC levels remained unchanged in aged mice, indicating a lack of PC to aPC conversion. Activation of fibrinolysis, determined by plasma d-dimer levels, was similar regardless of age or CLP severity, and plasminogen activator inhibitor-1, an inhibitor of fibrinolysis, showed severity-dependent induction independent of age. These results suggest that enhanced coagulation in aged mice during sepsis is due to dysfunction of the PC activation mechanism.

How I Teach a Thoracoscopic Lobectomy

Since the initial introduction of lobectomy by video-assisted thoracoscopic surgery (VATS) in the 1990s, there have been many studies comparing its efficacy with that of the standard thoracotomy approach. Currently, there are several demonstrated and recognized advantages of VATS lobectomy over thoracotomy [1]. Although a comprehensive discussion is beyond the scope of this manuscript, in summary VATS lobectomy has demonstrated and recognized superiority over thoracotomy in several areas: (1) perioperative outcomes: fewer respiratory complications, blood transfusions, cardiac arrhythmias, and shorter length of stay [2, 3]; (2) increased efficacy for higher risk populations (eg, elderly, poor pulmonary function) [4–6]; (3) improved cost effectiveness [7]; and (4) facilitated delivery of adjuvant chemotherapy for patients with N1–2 disease [8].

Laparoscopic Robot-Assisted Diaphragm Plication

Minimally invasive approaches to diaphragm plication for eventration include thoracoscopic and laparoscopic techniques. The elevated hemidiaphragm and ribs limit thoracoscopic techniques. We report our modification of the laparoscopic approach using robotic assistance with the da Vinci Surgical System, (Intuitive Surgical Inc, Sunnyvale, CA) to avoid single-lung ventilation, facilitate exposure, and allow more precise placement of plication sutures to achieve an even tension and maximum plication. Critical steps include creation of a small defect in the diaphragm to equalize pressures between cavities and placement of multiple, pledgeted interrupted horizontal mattresses.

Using a Regent Aortic Valve in a Small Annulus Mitral Position Is a Viable Option

BACKGROUND Outcome of mitral valve replacement in extreme scenarios of small mitral annulus with the use of the Regent mechanical aortic valve is not well documented. METHODS Records were examined in 31 consecutive patients who underwent mitral valve replacement with the use of the aortic Regent valve because of a small mitral annulus. RESULTS Mean age was 60 ± 14 years. Mitral stenosis or mitral annulus calcification was present in 30 of 31 patients (97%). Concurrent procedures were performed in 17 of 31 patients (55%). Median valve size was 23 mm. Mean mitral gradient coming out of the operating room was 4.2 ± 1.5 mm Hg and at follow-up echocardiogram performed at a median of 32 months after the procedure was 5.8 ± 2.4 mm Hg. CONCLUSIONS A Regent aortic mechanical valve can be a viable option with a larger orifice area than the regular mechanical mitral valve in a problematic situation of a small mitral valve annulus. Moreover, the pressure gradients over the valve are acceptable intraoperatively and over time.

The Story of ECLS: History and Future

Extracorporeal membrane oxygenation (ECMO) is a rapidly evolving field that was developed for critically ill patients with respiratory failure more than 40 years ago. Cardiopulmonary bypass (CPB) for cardiac surgery was first introduced in the 1950s. In the 1970s, CPB use at the bedside for pulmonary support began and was termed extracorporeal membrane oxygenation (ECMO). Later, in the 1980s, applications for extracorporeal technology expanded, and include oxygenation, CO2 removal, and hemodynamic support. Despite the other terms, such as extracorporeal life support (ECLS), ECMO is most often used to refer to all forms of extracorporeal support if gas exchange is involved. ECMO currently serves as a form of life support for critically ill patients when traditional supportive care is no longer effective. Recently, it has also become a bridge to transplantation and a way to manage acute shock.

Development and Clinical Use of an Artificial Lung

In the 1970s, the use of cardiopulmonary bypass at the bedside for critically ill patients with respiratory failure began and was termed extracorporeal membrane oxygenation (ECMO). Later, in the 1980s, applications for extracorporeal technology expanded, and included oxygenation, CO2 removal, and hemodynamic support. However, early studies regarding the use of ECMO for acute lung failure provided less than optimistic results. Today, recent research has created a renewed interest in such technology. There have been progressive advancements in artificial lung technology, and ECMO serves as a form of life support and as a bridge to transplantation for critically ill patients when traditional supportive care is no longer effective. These progressive advancements in artificial lung technology provide another tool in the critical care physician’s arsenal to combat this often fatal injury.