Initiating a minimally invasive cardiac surgery program–challenges and solutions

Background

Cardiac Surgery has evolved over past 50 years and has become a mature discipline. Minimally Invasive Cardiac Surgery techniques (MICS), warmly welcomed in the developed world, are still to take root in the developing countries. Minimally invasive approach represents a challenge in that it requires a new learning curve and carries apprehension about compromising the surgical results. As for the established surgeon, MICS necessitates a departure from the comfort zone and considerable metamorphosis.

Methods

Cardiac surgery has been carried at our centre for nearly two decades. Completing first year of our minimally invasive program we did 70 cardiac surgical cases from June 2011 to August 2012. These included 25 Mitral Valve Replacements (MVR), 30 Atrial Septal Defect closures (ASD), 10 Aortic Valve Replacement(AVR) and 5 Coronary Artery Bypass Grafting (CABG).

Results

There was no peri-op mortality. There were 2 conversions to standard sternotomy both in the early part of our learning curve. One patient developed right lower limb edema related to femoral vein cannulation.10 patients had minor air leak which settled spontaneously. There was one incidence of deep surgical site infection. The mean cross clamp time for ASD closure, MVR and AVR were 26.13 min, 51.10 min and 58.66 min respectively. The median Intensive Care Unit (ICU) stay was 2 days and the median hospital stay was 4 days.

Conclusion

The Cardiac surgery stage in the developing countries is ripe for the era of MICS. The unique patient population here stands to benefit most from it. Careful patient selection aiming to “tailor the operation to the patient and not the patient to the operation” is the crux of a successful MICS program.     

The Association of Center Performance Evaluations and Kidney Transplant Volume in the United States

Report cards evaluating transplant center performance have received significant attention in recent years corresponding with the Centers for Medicare and Medicaid Services issue of the 2007 Conditions of Participation. Our primary aim was to evaluate the association of report card evaluations with transplant center volume. We utilized data from the Scientific Registry of Transplant Recipients (SRTR) along with six consecutive program‐specific reports from January 2007 to July 2009 for adult kidney transplant centers. Among 203 centers, 46 (23%) were low performing (LP) with statistically significantly lower than expected 1‐year graft or patient survival at least once during the study period. Among LP centers, there was a mean decline in transplant volume of 22.4 cases compared to a mean increase of 7.8 transplants among other centers (p = 0.001). Changes in volume between LP and other centers were significant for living, standard and expanded criteria deceased donor (ECD) transplants. LPs had a reduction in use of donors with extended cold ischemia time (p = 0.04) and private pay recipients (p = 0.03). Centers without low performance evaluations were more likely to increase the proportion of overall transplants that were ECDs relative to other centers (p = 0.04). Findings indicate a significant association between reduced kidney transplant volume and low performance report card evaluations.     

Immature platelet fraction (IPF) determined with an automated method predicts clopidogrel hyporesponsiveness

The mechanisms for the variability in antiplatelet effects of clopidogrel are not elucidated entirely. Immature (reticulated) platelets may modulate the antiplatelet effects of clopidogrel but must be measured using flow cytometry. Whether new automated detection techniques yield similar results is not known. The objectives of the study to evaluate the role of immature platelets assessed by an automated method in response to the antiplatelet effects of clopidogrel. Twenty-nine healthy volunteers had platelet studies performed before and 1 week after 75 mg daily dosing of clopidogrel. Immature platelet fraction (IPF) was determined using an automated particle counter. Subjects were stratified into tertiles based on the IPF. Platelet studies included light transmission aggregometry (LTA), and vasodilator stimulated phosphoprotein phosphorylation (VASP-P) determined by platelet reactivity index (PRI). Baseline platelet aggregation responses to 2, 5 and 20 μM ADP, were similar in all three tertiles, however they were greater in the upper than in the lower tertile of immature platelets after clopidogrel in response to 5 μM ADP (54% vs. 23%, P = 0.02), with concordant trends for the other two concentrations. PRI was also greater in the upper tertile after clopidogrel (71.2% vs. 57.8%, P = 0.04). The frequency of clopidogrel hyporesponsiveness (aggregation >50% in response to 5 μM of ADP) was also higher in the upper tertile when compared to lower tertile, (60%) versus (10%) respectively (P = 0.0001). Immature platelets measured using an automated method, are associated with impaired response to antiplatelet effects of clopidogrel.     

An Efficient Mutual Authentication Framework for Healthcare System in Cloud Computing

The increasing role of Telecare Medicine Information Systems (TMIS) makes its accessibility for patients to explore medical treatment, accumulate and approach medical data through internet connectivity. Security and privacy preservation is necessary for medical data of the patient in TMIS because of the very perceptive purpose. Recently, Mohit et al.’s proposed a mutual authentication protocol for TMIS in the cloud computing environment. In this work, we reviewed their protocol and found that it is not secure against stolen verifier attack, many logged in patient attack, patient anonymity, impersonation attack, and fails to protect session key. For enhancement of security level, we proposed a new mutual authentication protocol for the similar environment. The presented framework is also more capable in terms of computation cost. In addition, the security evaluation of the protocol protects resilience of all possible security attributes, and we also explored formal security evaluation based on random oracle model. The performance of the proposed protocol is much better in comparison to the existing protocol.