To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Remote ischaemic pre-conditioning and cardiac ischaemic post-conditioning provide myocardial protection in cardiac surgery. However, these two endogenous strategies have not been directly compared in a clinical setting. The purpose of this study was to compare the efficacy of remote ischaemic pre-conditioning and post-conditioning in providing myocardial protection to children undergoing cardiopulmonary bypass for surgical repair of ventricular septal defect.
We randomly assigned 60 paediatric patients scheduled for surgical correction of congenital ventricular septal defect to the post-conditioning group (n = 20), remote pre-conditioning group (n = 20), or control group (n = 20). Post-conditioning consisted of 30 seconds of ischaemia and 30 seconds of reperfusion achieved by clamping and unclamping the aorta, repeated three times over 3 minutes immediately after cardioplegic arrest. Remote ischaemic pre-conditioning consisted of 5 minutes of lower limb ischaemia followed by 5 minutes of reperfusion using a blood-pressure cuff inflated to a pressure of 200 millimetres of mercury, also repeated three times over 30 minutes. We assayed creatine kinase-MB, troponin I.
Mean age, cardiopulmonary bypass times, and aortic cross-clamp times were matched across groups. Both post-conditioning and remote ischaemic pre-conditioning reduced the peak release of creatine kinase-MB (86.1 plus or minus 24.1 units per litre and 92.8 plus or minus 20.6 units per litre, respectively, versus 111.0 plus or minus 44.6 units per litre in the control, p less than 0.05) and troponin I (0.28 plus or minus 0.10 nanogram per millilitre and 0.26 plus or minus 0.09 nanogram per millilitre, respectively, versus 0.49 plus or minus 0.19 nanogram per millilitre in the control group, p less than 0.05).
Our study demonstrates that ischaemic post-conditioning and remote ischaemic pre-conditioning provide comparable myocardial benefit in children undergoing cold blood cardioplegic arrest.
Postconditioning by brief episodes of ischaemia performed just at the time of reperfusion have been shown to reduce the size of infarcts in animal models, and in the clinical setting of percutaneous cardiac intervention. The clinical applicability of postconditioning in cardiac surgery remains to be determined. We investigated the effect of postconditioning on myocardial protection in children undergoing cardiac surgery.
We randomly assigned 40 patients scheduled for surgical correction of congenitally malformed hearts under cold blood cardioplegic arrest to postconditioning or control treatment. Postconditioning was performed by two cycles of 30 seconds ischaemia and 30 seconds reperfusion using aortic reclamping, and declamping started 30 seconds after cardioplegic arrest. We assayed creatine kinase-MB, troponin I, transcardiac release of lactate and neutrophil counts.
The types of procedure, age, bypass and aortic cross-clamping times were similar in both groups. The postoperative peaks of creatine kinase-MB and troponin I were lower after aortic de-clamping in the postconditioned patients compared with their controls (128 ± 48 units per liter as opposed to 199 ± 79 units per liter, p = 0.016, and 0.34 ± 0.21 nanograms per milliliter as opposed to 0.61 ± 0.53 nanograms per milliliter, p = 0.05), with reduced inotropic scores in those submitted to postconditioning compared with their controls (4.8 ± 3.1 versus 2.3 ± 1.5, p = 0.036). Transcardiac release of lactate was reduced in the postconditioned patients compared with their controls (0.10 ± 0.27 as opposed to 0.37 ± 0.43 millimols per liter, p = 0.048). No differences between groups were found for transcardiac neutrophil count during reperfusion (10.8 ± 6.3% for postconditioning versus 14.0 ± 8.7% for controls, p = 0.48).
Our study demonstrates that postconditioning may protect the myocardium of children undergoing cold blood cardioplegic arrest. These data support the need for a larger clinical trial of postconditiong in children undergoing cardiac surgery.
Email your librarian or administrator to recommend adding this to your organisation's collection.