Monthly Archives: January 2013

Epidural as DVT prophylaxis

Cancer patients undergoing major oncologic surgery may decrease their risks of deep venous thrombosis(DVT) and Pulmonary Embolism(PE) by using an epidural for pain management. In a recent article published in JAMA Surgery(Previously Archives of Surgery) titled Thromboprophylaxis and Major Oncologic Surgery Performed With Epidural Anesthesia the surgical oncologists at Cedars Sinai note that in their retrospective analysis of their prospective database that their patients who underwent epidural anesthesia without chemical prophylaxis had similar rates of DVT to those that had chemical prohpylaxis.

epidural.

The author states that a previous review of 26 randomized controlled trials in surgical cancer patients yielded a DVT rate of 35.2% in those without any prophylaxis, 12.7% in those with chemical prophylaxis alone, and 5% with chemical and mechanical prophylaxis.  They then reviewed 119 patients of theirs that had an epidural and no chemoprophylaxis but did have mechanical prophylaxis and early ambulation, and noted that their asymptomatic screening ultrasounds had detected a 6.7% DVT rate and that only 0.8% had above knee thrombosis. Of note some of these patients did receive chemical prophylaxis after the epidural was discontinued.

I was previously unaware that spinal anesthetics had demonstrated decreased DVTs and would have expected these results only because of better pain control resulting in better and earlier ambulation.  The article cites several articles from orthopedic literature that demonstrate decreased thrombotic events with spinal anesthesia as well. Some of the theories of the mechanism for this include decreased sympathetic response with epidural anesthesia resulting in improved lower extremity blood flow and cite that sympathetic stimulation alters levels of coagulation factors resulting in increased Factor VIII, inhibited fibrinolysis, decreased antithrombin III, and increased platelet aggregation. Apparently the systemic absorption of local anesthetics can act as a anticoagulant.

Take away message for me: There may be some evidence that we can be less aggressive in chemical prophylaxis in patient with epidural anesthesia.

 

Surgical Simulator Nightmare

Once open surgery is dead and it’s all NOTES, and IR interventions, we will have this as our open surgery simulator! I want to get my FOS(Fundamentals of Open Surgery) pin to go along with my FLS(Fundamentals of Laparoscopic Surgery) pin.

You have to hand it to the creators of the game, apparently they made the simulator in less than 48 hours.

You can play the game here, but it requires a plugin install.

Literature Review: Anastomotic Leakage after Laparoscopic Rectal Cancer Operations

While the risk factors for anastomotic leakage have been well defined for open procedures, there is a paucity of data demonstrating the risk factors when the procedure is performed laparoscopically. The Korean Laparoscopic Colorectal Surgery Study group set out to generate this data and published it in the Annals of Surgery article Multicenter Analysis of Risk Factors for Anastomotic Leakage After Laparoscopic Rectal Cancer Excision.

This study utilized 11 hospitals and 12 surgeons between January 2006 and  March 2009 collecting data on 1734 patients who underwent laparoscopic surgery for rectal cancer. While there were many similarities in how these surgeons performed the surgery, the decision of whether or not to perform a protective ostomy varied widely among the surgeons and institutions with the low being 3.9% and the high 62.5%. They defined anastomotic leakage as passage of fecal materal from a drain, pelvic abscess, or peritonitis.

There were 101 leaks in the study giving a leak rate of 6.3% leak rate. On comparison between surgeons and institutions they found that surgeon prior experience did not affect the leak rate and neither did the caseload throughout the study. At institutions with the highest stoma rate, the leak rate was the lowest(4.6%) and 7.9% at the institution with the lowest rate.

Risk factors for leak were then analyzed using the whole data set and the non-diverted data set.

Diverted and Non-Diverted:

  • Male Gender(HR 1.943)
  • Advanced Tumor Stage(HR 2.842)
  • Perioperative Transfusion Requirement(HR 8.432)
  • Multiple Firings of the Linear Stapler(HR 7.849)

Non-diverted

  • Male Gender(HR 3.468)
  • Advanced Tumor Stage(HR 2.520)
  • Tumor Located Less than 7cm(HR 2.418)
  • Preoperative Chemoradation(HR 6.284)
  • Perioperative Transfusion Requirement(HR 10.705)
  • Multiple Firings of the Linear Staple(HR 6.181)

In addition to identifying the risk factors, they propose that any patient having 2 or more of these risk factors should undergo protective stoma formation secondary to the high risk of anastomotic dehiscience.

 

Additional Learning Points from the article:

  • Conventional open leak rates: 3.9 to 11
  • Open risk factors for leakage: Low Lying(below 7cm), Male sex, Advanced tumor stage, Multiple linear firings of the stapler, preoperative chemoradiation, and perioperative bleeding.
  • Increased risk of local recurrence, and reduced long term survival  after pelvic sepsis
  • Stoma closure morbidity rates 36.5%, Mortality rates 1.4%
  • Anastomotic leak rate traditionally has a 6% to 30% mortality rate.

Post-Surgical Emergency Department visits

I once had an attending physician on a busy service say that “If you don’t have a 20% re-consult rate on your consults you aren’t signing off fast enough.” After reading Postdischarge ED Visits Nearly as Frequent as Readmissions on the ACS Surgery News website I began to wonder if hospital administrators are going to start seeing post discharge emergency departments visits as “Never Events”. It just makes me wonder what is the acceptable rate of post discharge ED visits because as pressure goes up to decrease the length of stay it seems you are going to increase some of those ED visits.  Before I discharge patients I reiterate that before they go to the ED they need to call me, or if it’s an emergency they need to call me on the way in, mainly because I want to grab them out of the ED waiting room rather than having them wait several hours in a waiting room and get tests I wouldn’t have orered.  Despite all my efforts I still see patients go to the ED to get a simple question or to get issues resolved that easily could have been dealt with in clinic(sometimes being called to the ED from clinic to see these patients). I wonder if pressure on these metrics will have surgeons and hospitalists setting up their own urgent care setting that isn’t technically considered part of the ED to loophole this metric.

Randomized Controlled Trial: Laparoscopic Skills Program

A recent Annals of Surgery article reports a randomized controlled trial of a laparoscopic skills training program vs. conventional methods of training residents. The intervention program taught theoretical information about basic laparoscopy, and involved case based learning of the steps/techniques, relevant anatomy, possible complications and management of possible complications. Then it involved laparoscopic box training as well as use of the virtual reality simulator. They then compared these residents to the conventionally trained residents on their first five laparoscopic cholecystectomies and reported that the intervention group outperformed the conventionally trained residents and claim that they effectively moved the learn curve out of the operating room and into the skills lab.

No one is really surprised that more effort and more practice gave better results, but I think that residency is too short to spend a lot of time in a skills center. Ideally these kinds of basic skills training sessions should be done by 4th year medical students going into surgery so that they can hit the ground running once they have an MD behind their name.  Unfortunately, surgery residencies and medical schools aren’t likely to put the effort in to train a 4th year medical student that isn’t for sure doing their residency at that program. Maybe surgery residencies will reach out to incoming interns in there 4th year with online curriculum for the last 3 months of medical school.

 

Annals of Surgery: Validation of a Structured Training and Assessment Curriculum for Technical Skill Acquisition in Minimally Invasive Surgery: A Randomized Controlled Trial