Vitamin D and Postoperative Vasopressor Use in Cardiopulmonary Bypass

Vitamin D and cardiovascular diseases

Vitamin D has an established role in calcium homeostasis but its deficiency is emerging also as a new risk factor for cardiovascular disease (CVD). In particular, several epidemiological and clinical studies have reported a close association between low vitamin D levels and several cardiovascular risk factors and major CVDs, such as coronary artery disease, heart failure, and cardiac arrhythmias. In all these clinical settings, vitamin D deficiency seems to predispose to increased morbidity, mortality, and recurrent cardiovascular events. Despite this growing evidence, interventional trials with supplementation of vitamin D in patients at risk of or with established CVD are still controversial. In this chapter, we summarize the currently available evidence on the links between vitamin D deficiency and major cardiovascular risk factors and CVD, in terms of both clinical relevance and potential therapeutic implications.

Effect of Vitamin D Supplementation on Postoperative Outcomes in Cardiac Surgery Patients: A Systematic Review

Background Vitamin D deficiency is a very common occurrence in cardiac patients. It has been proved that cardiac surgery and cardiopulmonary bypass accelerate the deficiency further. The postoperative outcomes of patients deteriorate in the presence of vitamin D deficiency. Perioperative supplementation of vitamin D is the only solution to the problem. Hence, the present systematic review was conducted to derive the efficacy and safety of vitamin D supplementation on postoperative outcomes in cardiac surgery patients.

Method Publications over duration of last 10 years was searched from different database and web sites. The data from full-text research articles were analyzed for the effect on different postoperative outcomes and side effects.

Result Eight randomized control trials were retrieved on the effect of perioperative vitamin D supplementation in cardiac surgery patients and their postoperative outcomes. Six articles (75%) were found to be in favor of improvement in postoperative outcome. Two articles (25%) did not find any difference of outcome between the control and treatment group. All the studies observed the restoration of vitamin D to normal and no adverse effects from supplementation.

Conclusion Perioperative vitamin D supplementation improves the postoperative outcomes after cardiac surgery. It is effective and safe to supplement vitamin D in cardiac surgery patients.

Vasoplegia in patients following ventricular assist device explant and heart transplantation

BACKGROUND

Vasoplegia has been shown to be associated with increased morbidity and mortality in patients undergoing cardiac surgery. It has been previously stated that low pulsatile states as seen with current left ventricular assist devices (LVADs) may contribute to vasoplegia post LVAD-explant and heart transplant. We sought to examine the literature regarding vasoplegia in the post-operative setting for patients undergoing LVAD explant and heart transplant.

METHOD

A literature review was conducted to firstly define vasoplegia in the setting of LVAD patients, and secondly to better understand the relationship between vasoplegia and LVAD explantation in the postoperative heart transplant patient cohort. A keyword search of 'vasoplegia' OR 'vasoplegic' AND 'transplant' was used. Search engines used were PubMed, Cochrane Library, ClinicalTrials.gov, Ovid, Scopus and grey literature.

RESULTS

17 studies met the selection criteria for review. Three key themes emerged from the literature. Firstly, there is limited consensus regarding the definition of vasoplegia. Secondly, patients with LVADs experienced higher rates of vasoplegia following heart transplant than their counterparts and thirdly, increased cardiopulmonary bypass time was associated with a higher rate of vasoplegia.

CONCLUSION

Vasoplegia is not clearly defined in the literature as it pertains to the LVAD patient cohort. Patients bridged with LVADs appear to have higher rates of vasoplegia, however the aetiology of this is unclear and may be associated with continuous flow physiology or prolonged cardiopulmonary bypass time. A universal definition will aid in risk stratification, early recognition and management.