Reply

Sir: We appreciate the enthusiastic letter to the Editor regarding our article, “Practical Guidelines for Venous Thromboembolism Chemoprophylaxis in Elective Plastic Surgery,” a synopsis of the author’s views in which he favors sedation and limited operative time over chemoprophylaxis.1–3 We appreciate the chance for further discussion on our article, which we hope provides practitioners with clinical recommendations and practical guidelines over the usual hypothetical analysis. To quote the author, “none of us is immune to our own prejudices.”1 It would seem that applies to himself as well as to us. Regarding the comment that we did not address or rebut the opposing viewpoint, this published author should observe paper submission dates. The practical guideline was received April 9, 2014, meaning that four of Dr. Swanson’s five articles postdate our submission. After over a dozen years of teaching, writing, and interest in this subject, the most gratifying part is that it has garnered so much interest in recent years. The fact that we as a specialty are even thinking about thromboembolism as a patient risk, particularly in elective surgery, is ultimately the success of our field. What has not changed in that time is the passionate feedback about how some practitioners do not have this issue because they perform their technique this way or that way, they have quicker operations, or their patients are better educated. Although this may withstand cursory inspection, these types of statements tend to incorporate anecdotal reasoning and lead to misdirected recommendations, or in other words, post hoc ergo propter hoc: the logical fallacy. In 2004, the corresponding author (S.P.D.) proposed an elective prospective prophylaxis study using ultrasound to screen for postoperative deep venous thrombosis. The estimate of enrollment for any statistical significance based on incidence was over 6000 patients, a number that more than exceeds the report noted with as yet unpublished data on 203 patients.4,5 Although this creates an interesting discourse on potential confounding variables or clinical circumstances, the reader needs to be especially cautious of such reports that incorporate a type II error following insufficient statistical power. With regard to well-powered and elegantly designed clinical studies, credit needs to be given to Dr. Pannucci in this regard, who has taken up the mantle and performs some of the best experimental work on venous thromboembolism. It would be more appropriate than the skepticism by Dr. Swanson1 when he describes that Dr. Pannucci has written extensively in favor of anticoagulation including four Plastic and Reconstructive Surgery articles in the past 2 years. His opinions may have been formed by the largest venous thromboembolism prevention study, with over 3000 patients. This is what we know: deep venous thrombosis is generally a silent event, of which we have no real idea how many of our elective patients are affected. It is an event where the first symptoms are often from progression to pulmonary embolism or even death. Since this article was accepted, there have been three venous thromboembolism–related deaths in the Washington, D.C., plastic surgery community. With this in mind, a surgeon who at least considers either a procedure-based or risk-assessment model tailored to each patient is ahead on safety compared with one who does not. Paradoxically, the author has adopted a procedure-based reduction model, in which he limits time and uses sedation, which works for him based on his data, and this we applaud. This article is to help others that have anesthesiologists that only provide general anesthetics, hospitals that insist on a mandatory approach to chemoprophylaxis with patient populations at risk, or those that seek advice on timing and dosing of anticoagulation should they choose to use it.4 However, the use or omission of mechanical or chemoprophylaxis should not be viewed as a choice between the lesser of two evils, specifically, hematoma or venous thromboembolism. There is a delicate balance of bleeding risk versus protection, although this can be carefully managed and considered in patients based on individual operative techniques and patient populations. This is the goal of the venous thromboembolism prophylaxis guidelines: to provide a reference for the surgeon and practitioner to safely and efficiently manage these risks and optimize the safety of their patients. In our source article, the 12.5 percent hematoma rate was for the whole study group; of those that bleed, a quarter were on therapeutic intravenous heparin drips. When you analyze the raw data in context, as opposed to skewed individual data points to make your point,1 you see a different picture. The rates of hematoma were comparable between patients on mechanical prophylaxis plus subcutaneous heparin versus mechanical prophylaxis (6.7 percent versus 6.3 percent; p = 1.000.) Yet the rate of thromboembolism was 0 percent for anticoagulation versus 14.6 percent without (p = 0.013), thus our prejudice. In our recommendation, we appreciate that a hematoma is a significant problem. As such, we have shifted the chest recommendation from a half hour to greater than 1-hour operations to better tailor to an elective practice. In addition, we have addressed management of birth control and hormone therapy as a form of chemoprophylaxis. The development of the Venturi Davison Caprini order form was a hybrid procedure based on procedure and risk assessment to facilitate practiced ease of use compared with many hospital-based regimens. We suggest the author reread the article where both reduced time and sedation are acknowledged as protective, and consider referencing them to support his own position.6 We are appreciative that the membership and specialty have discourse about this critical subject. It can only help the continued advocacy for our patients and the advancement of our field as a whole. DISCLOSURE The authors have no financial interests in any of the products or techniques mentioned and have received no external support related to this communication. Matthew L. Iorio, M.D. Division of Plastic Surgery Beth Israel Deaconess Medical Center Harvard Medical School Boston, Mass. Steven P. Davison, D.D.S., M.D. DAVinci Plastic Surgery Washington, D.C.