Thrombotic risk in central venoarterial extracorporeal membrane oxygenation post cardiac surgery.

INTRODUCTION: Post-cardiotomy cardiogenic shock is an accepted indication for venoarterial extracorporeal membrane oxygenation. The true incidence and risk factors for the development of thrombosis in this setting remain unclear. METHODS: Patients supported with central venoarterial extracorporeal membrane oxygenation due to ventricular dysfunction precluding weaning from cardiopulmonary bypass were retrospectively identified. Electronic records from a single institution spanning a 4-year period from January 2015 to December 2018 were interrogated to assess the incidence of thrombosis. The relationship to exposures including intracardiac stasis and procoagulant usage was explored. RESULTS: Twenty-four patients met the inclusion criteria and six suffered major intracardiac thrombosis. All cases of thrombosis occurred early, and none survived to hospital discharge. The lack of left ventricular ejection conferred a 46% risk of developing thrombosis compared to 0% if ejection was maintained (p = 0.0093). Aprotinin use was also associated with thrombus formation (p = 0.035). There were no significant differences between numbers of patients receiving other procoagulants when grouped by thrombosis versus no thrombosis. CONCLUSION: Stasis is the predominant risk factor for intracardiac thrombosis. This occurs rapidly and the outcome is poor. As a result, we suggest early left ventricular decompression. Conventional management of post-bypass coagulopathy seems safe if the aortic valve is opening.

Transversus abdominis: changes in thickness during the unsupported upper limb exercise test in older adults.

Novel, short-lived upper limb tasks performed by young adults have been used to investigate the role of transversus abdominis (TrA) in maintaining postural stability. Little information exists concerning the behaviour of TrA in older adults during protracted postural challenges. The primary aim of this study was to describe the change in thickness of TrA during an incremental upper limb exercise test in older adults. A secondary analysis was undertaken to compare the results between younger and older subjects. Healthy subjects aged between 40 and 70 years performed the Unsupported Upper Limb Exercise Test (UULEX) while activity of TrA was continuously monitored by using rehabilitative ultrasound imaging. Changes in muscle dimensions were measured every minute during the test. The thickness of TrA increased significantly and exponentially between minutes 8 and 13 of the UULEX. Although there was a significant difference between older and younger subjects in absolute measures of TrA thickness, the change in TrA thickness as a percentage of resting thickness during the UULEX demonstrated an identical pattern between younger and older subjects. This study suggests that TrA is continually and increasingly active during an upper limb task in both younger and older asymptomatic subjects.