[HSF] Inotropes, ventricular fibrillation and myocardial protection

[erdinç naseri]

Ani,
Agree with the first part of your argument.Will you comment also on very long cross clamp times.
erdinc> From: anianyanwu at hotmail.com> To: openheart-l at lists.hsforum.com> Subject: RE: [HSF] Inotropes, ventricular fibrillation and myocardial protection> Date: Thu, 26 Jul 2007 01:04:42 +0000> > At the risk of finding myself in my usual lonely corner, I must challenge a view that has been brought up repeatedly on HSF, often by Prasanna but also I think supported by Drs Frater and Salerno amongst, I suspect, many others. I feel if no one challenges these things they gradually become dogma on the forum, and those of us who don't fit into the expected norm increasingly get marginalised as a lesser species of surgeon.> > What I am challenging is the assertion that 1) Use of inotropes after heart surgery denotes inadequate myocardial protection after cardiac surgery and 2) Occurrence of Ventricular arrythmia after removal of cross-clamp denotes inadequate protection.> > I would argue neither is the case. The use of inotropes is greatly physician dependent rather than myocardium dependent. The number one factor driving inotrope use is the physician preference. While Prasanna may chose to use inotropes only when clearly indicated, many others have a lower threshold for doing so for various reasons, some of which have no connection to myocardial preservation. I know of surgeons, mainly private surgeons who are not blessed with as residents to take care of their patients as those in academic centers, who place every patient on a moderate amount of dobutamine or alternative, so in the middle of the night they have a drug to titrate in case of issues. I also know, for example, that in Melbourne they use milrinone on all CABGs because of their use of multiple arterial grafts. Some others use pulmonary artery catheters routinely and believe in use of inotropes to maintain specific goals. Some surgeons believe also in having a good nights sleep as myocardial depression, not infrequently, becomes apparent, not when the clamp is removed but hours later when everyone is in bed.> > I think it depends also on your practice. I think if one's practice is mainly CABG, congenital or valve stenosis then the above might hold, but for surgeons who operate mainly on dysfunctional ventricles I am not sure same holds. If you use ischemic arrest (i.e. not warm beating technique) by definition you have ischemic injury. If then you start with an impaired ventricle, by definition the ventricle is more impaired afterwards. How then can it be seen as a sin if you start the patient on an inotrope preemptively? In my set-up a lot of our patients have heart failure and MR - on many an occasion the LV struggles after correcting the MR, how can one say that use of inotropes means I did not protect the heart well? Indeed some surgeons prophylactically place IABP when operating on the dyfucntional LV so how could using inotropes post-op mean one has failed to protect the heart.> > As regards the second point maybe those surgeons who do protect the heart well no longer need defibrillator paddles in their OR set. For me I see it all when I take clamp off - arrythmias, atrial and ventricular . Sometimes I see asytole and I pace, sometimes I see SR and do nothing. To be honest I attach no import to what I see and in my mind have not observed any correlation with what happens after. I have worked with several senior surgeons and to date have none that attaches this importance to the rhythm after clamp is removed because frankly I think there are far more important things that matter and it is those that will determine patient outcome.> > Enough said as I know this is a minority report, as always, and will incur the wrath of the believers. But then the minority position is one I am used to on here; some things however have to be said by somebody!> Ani> > > > > > >> > > 7 The best paramenter is that the patient should be weaned with minimal > Inotropes - 3mics dopa _ dobut and for RVOT issues (TOF/Infundibular PS) > 0.35 mics Milrinone. Anything more = inadequate protection based on the > near hit miss. Also release of X clamp must not result in Vtach / Vfib. > > > Prasanna> >> _________________________________________________________________> The next generation of MSN Hotmail has arrived - Windows Live Hotmail> http://www.newhotmail.co.uk_______________________________________________> OpenHeart-L mailing list> > Send postings to:> OpenHeart-L at lists.hsforum.com> > To UNSUBSCRIBE, to CHANGE email address, or to view archives:> http://mmp.cjp.com/mailman/listinfo/openheart-l> > All messages transmitted by the OpenHeart-L are subject to the policies and > disclaimers posted at:> http://www.hsforum.com/listdisclaim> -----------------------------------------