762 Toneva et al Discussion J Am Coll Surg

16. Howard DD, White CQ, Harden TR, Ellis CN. Incidenceof surgical site infections postcolorectal resections withoutpreoperative mechanical or antibiotic bowel preparation. AmSurg 2009;75:659e663; discussion 663�654.

17. Kobayashi M, Mohri Y, Inoue Y, et al. Continuous follow-upof surgical site infections for 30 days after colorectal surgery.World J Surg 2008;32:1142e1146.

18. Smith RL, Bohl JK, McElearney ST, et al. Wound infectionafter elective colorectal resection. Ann Surg 2004;239:599e605; discussion 605�597.

19. Nichols RL, Broido P, Condon RE, et al. Effect of preopera-tive neomycin-erythromycin intestinal preparation on the inci-dence of infectious complications following colon surgery. AnnSurg 1973;178:453e462.

20. Bellows CF, Mills KT, Kelly TN, Gagliardi G. Combinationof oral non-absorbable and intravenous antibiotics versus intra-venous antibiotics alone in the prevention of surgical site infec-tions after colorectal surgery: a meta-analysis of randomizedcontrolled trials. Tech Coloproctol 2011;15:385e395.

21. Solla JA, Rothenberger DA. Preoperative bowel preparation. Asurvey of colon and rectal surgeons. Dis Colon Rectum 1990;33:154e159.

22. Markell KW, Hunt BM, Charron PD, et al. Prophylaxis andmanagement ofwound infections after elective colorectal surgery:a survey of the American Society of Colon and Rectal Surgeonsmembership. J Gastrointest Surg 2010;14:1090e1098.

23. Lewis RT. Oral versus systemic antibiotic prophylaxis in elec-tive colon surgery: a randomized study and meta-analysis senda message from the 1990s. Can J Surg 2002;45:173e180.

24. Nelson RL, Glenny AM, Song F. Antimicrobial prophylaxisfor colorectal surgery. Cochrane Database Syst Rev 2009;(1):CD001181.

25. Davis CL, Pierce JR, Henderson W, et al. Assessment of thereliability of data collected for the Department of VeteransAffairs national surgical quality improvement program. J AmColl Surg 2007;204:550e560.

26. Khuri SF, Daley J, Henderson W, et al. The Department ofVeterans Affairs’ NSQIP: the first national, validated,outcome-based, risk-adjusted, and peer-controlled programfor the measurement and enhancement of the quality ofsurgical care. National VA Surgical Quality ImprovementProgram. Ann Surg 1998;228:491e507.

27. Khuri SF, Daley J, Henderson W, et al. Risk adjustment of thepostoperative mortality rate for the comparative assessment ofthe quality of surgical care: results of the National VeteransAffairs Surgical Risk Study. J Am Coll Surg 1997;185:315e327.

28. Cannon JA, Altom LK, Deierhoi RJ, et al. Preoperative oralantibiotics reduce surgical site infection following electivecolorectal resections. Dis Colon Rectum 2012;55:1160e1166.

29. Dimick JB, Chen SL, Taheri PA, et al. Hospital costs associ-ated with surgical complications: a report from the private-sector National Surgical Quality Improvement Program.J Am Coll Surg 2004;199:531e537.

30. Kelly M, Sharp L, Dwane F, et al. Factors predicting hospitallength-of-stay and readmission after colorectal resection: a pop-ulation-based study of elective and emergency admissions.BMC Health Serv Res 2012;12:77.

31. Messaris E, Sehgal R, Deiling S, et al. Dehydration is the mostcommon indication for readmission after diverting ileostomycreation. Dis Colon Rectum 2012;55:175e180.

32. Wren SM, Ahmed N, Jamal A, Safadi BY. Preoperative oralantibiotics in colorectal surgery increase the rate of Clos-tridium difficile colitis. Arch Surg 2005;140:752e756.

33. Krapohl GL, Phillips LR, Campbell DA Jr, et al. Bowel prep-aration for colectomy and risk of Clostridium difficile infec-tion. Dis Colon Rectum 2011;54:810e817.

Discussion

DR ROBERT CIMA (Rochester, MN): In brief, the authors havepresented a multisite review from the Veterans Administration

(VA) hospitals on the impact of oral antibiotic preparation, eitheralone or as part of a mechanical bowel preparation, on postopera-tive length of stay and readmissions after elective colorectal surgery.

They make use of the VA surgical quality improvement projectdata to evaluate 30-day outcomes in patient demographics, comor-bidities, and procedure codes. They also used the VA pharmacydatabase to correlate the prescriptions that were provided, and as

they pointed out, were unable to determine whether or not thedrugs were taken for the prescriptions of mechanical bowel prepa-ration and/or oral antibiotics.

As the authors have presented, they found an association betweenthe prescription for an oral antibiotic bowel preparation witha decreased length of stay and readmission. The primary driver for

this decreased length of stay was infectious complications or adecrease in infection complications associated with the prescriptionof oral antibiotics. The authors mentioned that surgical site infection(SSI) was the primary driver after colorectal surgery, and I have

a number of questions related to that.The time period of the study is from 2005 to 2009, and this

corresponds to an interesting period for recent surgical practice,

namely, to the implementation of numerous interventions to reduceSSI, such as the Surgical Care Improvement Project (SCIP) nationalmeasures. Also, just an inherent look at people’s practice has shown

improvement. Was there a time trend analysis performed over these5 years to determine whether or not there was any difference?

Given the implementation of SCIP protocols as a national

quality metric during this very same time period and a concertedeffort by the VA administration to consolidate and streamline anti-biotic use, was there a change in antibiotic stewardship as far as IVantibiotics, as far as dosing, types of antibiotics, and discontinua-

tion that could possibly confound the findings of this study?Also, there was an intense effort in the VA to reduce SSI across

the board. Another very important paper released in the NewEngland Journal of Medicine from 2010, which corresponded tothis very time period, showed that in a randomized time trial per-formed in the VA and quickly disseminated through the VA, that

the type of skin preparation alone reduced SSI by 40%. So werethere any systematic changes within the VA that could be potentialconfounders for this case?

Can you explain why this population-based study, as well asthe Michigan collaborative, which you mentioned had similar find-ings, which found that oral antibiotic bowel preparations playedsome type of role or an association with decreased SSI, is contrary

to 20 years of data from randomized controlled trials? These trials

Vol. 216, No. 4, April 2013 Toneva et al Discussion 763

have shown that there was no benefit to SSI, which has led to thedecreased use of oral antibiotics in preference to IV antibiotics

appropriately administered.Last, the authors discuss enhanced recovery pathway. As most

people know, enhanced recovery pathway after surgery is a change

in the physiologic response to surgery, and essential to that is notdisturbing the physiology beforehand. We reported from theMayo Clinic a number of studies looking at our enhanced recovery

pathway, which omits oral bowel preparation of any type. Forsegmental colectomies, 50% of patients leave on postoperativeday 2. So how do we counterbalance these 2 different processes?

DR ELIZABETH WICK (Baltimore, MD): Colorectal SSI isa vexing problem. And despite significant efforts to increase

compliance with SCIP measures, this has really failed to translateinto improved outcomes. To move forward, we really need to iden-tify processes that are linked to outcomes.

At Hopkins, to address SSIs, we have adopted the comprehen-

sive unit-based safety program developed in the ICUs to addresscentral, unassociated bloodstream infections in the perioperativesetting. With this program, we have improved operating room

culture by engaging and empowering frontline staff to help addressdefects and improve processes. With this, we have reduced SSIsby 33%.

We have now extended this work nationally through a fundedcollaborative, with the goal of reducing SSIs in colon surgerypatients in more than 100 hospitals. We are currently enrollinghospitals. And the common theme we hear from hospitals is they

are really looking for emerging evidence of processes demonstratedto improve outcomes. And I applaud the authors of this paper fortaking us in this direction. I have a few questions.

First, was there any difference in the impact of mechanical bowelpreparation and oral antibiotics on outcomes in patients who werepreadmitted vs admitted the same day of surgery?

In our experience, compliance on an outpatient basis withmechanical bowel preparation and oral antibiotics is in the rangeof 50% to 75%. So, actually, the impact may be greater than

you appreciated.Second, did the type of bowel preparation affect the rate of

reoperation or re-exploration?Next, did you have a chance to review the microbiology associ-

ated with the wound infections and the different bowel prepara-tions with the question, did bowel preparation alter the pathogenin the wound infections?

Finally, did oral antibiotics plus mechanical bowel preparationhave a greater impact on SSIs diagnosed pre- vs postdischarge, asthis might help guide us in our readmission efforts?

DR MATTHEW WALSH (Cleveland, OH): I don’t think we aregoing ever come down to zero for SSIs. And I’m wondering if

you know the time after discharge that the readmissions occurred,

and is it possible that if outpatient visits had occurred, thesepatients could have been managed as outpatients and not as

readmissions?

DR MELANIE MORRIS (Birmingham, AL): Dr Cima, you hadseveral questions, and I will try to summarize them briefly. Our

data set is the SCIP cohort, so we assessed adherence to theSCIP measures. We previously reported that over the 5-year studyperiod, there was increased adherence to SCIP measures from 70%to more than 90%, but, with this, there was no change in SSI rates.

We did not know which skin preparation was used on thesepatients. We were unable to obtain that data from the VA dataset.

There has been a lot of literature, certainly over the past 20 years,

as to whether we should be performing bowel preparations. Manyrecent studies looked at mechanical bowel preparation and didnot necessarily measure whether the oral antibiotic bowel prepara-

tion was used. So I believe that, over time, as mechanical bowelpreparation was abandoned, oral antibiotics fell off as well. Butthere are good recent studies, including the Michigan study andour study, which would support the continued use of oral

antibiotics.Certainly, enhanced recovery protocols have proven beneficial in

colorectal surgery. And I think addition of an oral and mechanical

bowel preparation will further help us care for these patients in themost efficient and safest way possible.

Dr Wick, you asked about preadmitted patients vs patients who

were admitted on the day of surgery. We did look at this, and wefound that there was no difference in these patient populations. Wealso looked at patients who had to return to the operating room.

We found that 6% of patients who had an oral antibiotic bowelpreparation, 7% of patients who had a mechanical bowel prepara-tion, and 10% of patients who had no preparation at all had toreturn to the operating room.

You asked an excellent question about infectious complicationsand what the pathogens were. Unfortunately, we are not able toidentify the organisms responsible for the infection. The VA hospi-

tals report culture data differently, so there’s not currently a system-atic way to collect these data.

We also looked at the percentage of SSIs that were diagnosed

predischarge and those diagnosed postdischarge. We found thatthe patients with the oral antibiotic bowel preparation had theshortest length of stay. They also had slightly more SSIs diagnosedpostdischarge. However, this was not statistically significant. So

that tells us that SSI alone is not what’s driving the readmissionrates.

Finally, Dr Walsh, we do know the median time from discharge

to readmission in our cohort. And the median was 8 days. So,certainly, it’s possible that there could be some interventions per-formed during that time, such as potentially short-term follow-

up to help treat these SSIs, and maybe we could intervene andprevent some of the readmissions.