NEW HORIZONS IN SURGERY
| SAFE INCORPORATION OF NEW TECHNOLOGY INTO CLINICAL PRACTICE —Jon A. Van Heerden, MD, Professor
of Surgery, Mayo Clinic Medical School and Mayo Clinic, Rochester, MN
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 | Patient-surgeon covenant: surgeons need formal training in use of new technologies; should treat patients as they would
wish to be treated and place patients’ interests above all else
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| Technology “smorgasbord”: new techniques include diagnostic ultrasonography (US) and gamma probe applications;
cardiovascular—off-pump coronary artery bypass (CAB), robotic cardiac surgery; vascular—endovascular balloon
angioplasty, repair of aneurysms, placement of stents; colorectal—endorectal US, laparoscopic colon resection;
thoracic—robotic surgery, thoracoscopy, laparoscopy; important to choose technology wisely and use it properly
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| Principles of evidence-based medicine: define question or problem; evaluate literature to find supportive evidence; apply
results; audit outcomes (eg, operative mortality, length of stay; be prepared to share with patient and third-party payers)
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| Laparoscopic cholecystectomy: model—McGill University; surgeons began maintaining prospective database,
starting with first patient in 1990; also started randomized controlled trial comparing new technology to mini-open
cholecystectomy; open procedure abandoned after studying 124 patients (62 for each procedure) because of obvious
advantages of laparoscopic cholecystectomy
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| Impact of technology on patient: laparoscopic cholecystectomy—benefits to patient self-evident; however, negative aspects
rarely emphasized; drawbacks include risk of cutting bile duct, trocar injuries to aorta, inferior vena cava, and
viscera; death
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| Laparoscopically assisted colectomy: quality-of-life outcomes (JAMA 2002)— should not be offered to patients
with colon cancer; should not be recommended for clinical practice until safety demonstrated; should not be performed
outside of clinical trials; compared to open surgery (study results, 2006)—laparascopic procedure took longer; complication
rates same; 30-day mortality same; cancer recurrence after 3 yr same; recurrence in surgical sites and in trocar
wounds same; overall survival same
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| Operative mortality: speaker believes term should be abandoned; not acceptable to patient, family, referring physician,
nurses, or to surgeon; use for comparative analysis only
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| Impact of new technology on job performance and satisfaction (Rattner, 2005): improved operating room
function; surgeons more confident but more emotionally exhausted; nurses bored but less emotionally exhausted; rates of
burnout highest among surgeons with 6 to 10 yr of experience, especially general surgeons; CAB—in Canadian study,
mortality and perioperative morbidity improved up to year 10, then leveled off; data support mentoring of new surgeons
by more experienced practitioners for 1 to 2 yr; thyroidectomy and parathyroidectomy—chest and axillary approaches
being advocated with no supporting evidence
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| Regulation: unclear who actually regulates use of new technology, eg, laparoscopic cholecystectomy; each surgeon most
important regulator; surgeons should ask whether they would want themselves using technology on their own children
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| Findings of American College of Surgeons Committee on Emerging Surgical Technology and Education (CESTE): in
1998, studied introduction of new interventional procedures in Australasia; Australasian Safety and Efficacy Review
of New Interventional Procedures-Surgical (ASERNIP-S) provides quality timely assessment of emerging technology,
publishes evidence-based review of existing data and literature; recommends incorporation into practice or feasibility
study; based on study findings, may recommend incorporation, abandonment, or use in protocol only
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| National Surgical Quality Improvement Program (NSQIP): study overseen by Veterans Affairs (VA), following patients
(1.3 million to date) undergoing major procedures; started in 1991; initial findings (1993) disappointing; launched effort
to improve results; by 2001, operative mortality decreased by 27%, morbidity by 45%; median length of stay went
from 9 to 4 days; patient satisfaction increased
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| Education in new technology: options include numerous courses; sabbatical at center of excellence; courses using animals;
mentoring programs; future training will incorporate virtual reality and simulation; telemedicine, telemonitoring,
and telerounding programs also available in some places; surgeons must learn to balance technological advancements
with ethical responsibilities
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| SEARCHING FOR THE LEAKPROOF ANASTOMOSIS —James Fleshman, MD, Professor of Surgery, and Chief, Colorectal
Surgery, Washington University, School of Medicine, St. Louis, MO
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| Background: impact of anastomotic leaks depends on timing, ie, during surgery, within 7 days of surgery, or delayed;
evidence that fixing leaks detected during surgery reduces future impact (may indicate extension of surgery, eg, diversion);
exact contribution of preventive measures to reducing risk for leaks unknown
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| Anastomoses at highest risk of leaking: extremely low, colorectal (ileorectal, anorectal); right-sided ileocolic and small
bowel-to-small bowel anastomoses “fairly well protected” and not major concern
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| Diversion: less preventive measure than reduction of potential impact of leak
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| Bowel preparation: preventive impact less than previously thought, but may help improve outcome of leak
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| Wrapping omentum: reduces risk for leaks by providing additional source of blood to level of anastomosis
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| Draining: in some studies, actually increases number of leaks through erosion or damage to anastomosis
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| Mobilization of splenic flexure in low anterior anastomosis: increases blood supply and decreases tension at anastomosis;
“may really prevent leaks”
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| Factors that affect healing: some data show no difference between anastomotic leak in hand-sutured anastomoses,
compared to double-stapled anastomoses; tissue welding has not yet reproduced results obtained with mechanical
anastomoses; few ways known to enhance blood supply; not yet possible to reliably say blood supply adequate and
anastomosis will not leak
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| Tissue characteristics: depend on disease process and treatment before surgery (eg, neoadjuvant therapy, immunosuppression);
nutrition and adequate bowel mobility must also be considered
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| New approaches: covering anastomosis with fibrin glue (makes little sense, as pressure comes from inside anastomosis);
wrapping anastamosis with material other than omentum (benefit uncertain also, due to pressure at junction); bolstering
anastomosis from within with extra material to prevent gaps may be helpful; local diagnostics (eg, oximetry, Doppler imaging)
may be helpful; combination of measures may prove most beneficial
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| Anastomotic leaks associated with laparoscopic surgery for rectal cancer: leak rates vary; may depend on
distance of anastomosis from anal canal, use of total mesorectal excision, and ability to mobilize splenic flexure; procedure
and definition of anastomosis must be standardized; randomized controlled trial planned
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| Experiments with two new techniques
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| Bolstering: biomaterial (Alloderm [LifeCell]; decellularized skin) placed between two layers of intestine as staples
passed through; fills gaps and is incorporated into anastomosis; did not burst when pressure applied to staple line (regular
anastomosis did burst); conclusion—strengthens anastomosis
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| Compression anastomosis: nickel titanium (nitinol) ring applies steady pressure at anastomosis; elimination of anastomotic
gaps during surgery could prevent some leakage; xymographic and histologic data suggest both types of anastomoses
resemble stapled ansatomosis at 2 wk
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| IS BOWEL PREPARATION NECESSARY? —Scott A. Strong, MD, Staff Surgeon, Department of Colorectal Surgery,
Cleveland Clinic, Cleveland, OH
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| Intestinal flora: concentration increases distally; large intestine contains anaerobes Bacteroides and Bifidobacter; concentration
1000 to 10,000 times greater than that of Escherichia coli; preparation agents include monobasic and dibasic
sodium phosphate (Fleet Phospho-soda) and polyethylene glycol-based agents
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| Fleet Phospho-soda: cathartic; contraindicated in more patients than polyethylene glycol preparations (isosmolar); contraindications
include pregnancy, lactation, renal failure, and congestive heart failure; may induce hypokalemia and
cardiac arrhythmias in patients who take diuretics or digitalis
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| Results of recent meta-analysis: covered 9 randomized controlled trials involving ≈1600 patients; unprotected anastomoses
created in all cases; among patients undergoing mechanical bowel preparation, wound infection rate 7.4%,
compared to 5.4% among those without preparation; leak rate associated with bowel preparation double that with no
preparation; no significant difference in mortality between groups; odds ratio for wound infection 1.45 in favor of no
bowel preparation (highly statistically significant); odds ratio for anastomotic leaks 2.03; pattern similar whether resection
colonic or rectal; conclusion—mechanical bowel preparation associated with increased incidence of anastomotic
leak, compared to no preparation
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| Explanation of findings: bowel preparation associated with mucosal changes, eg, decreased mucus, greater infiltration of
inflammatory cells; spillage associated with higher risk for wound infection; Israeli study—suggested possible higher
risk for spillage among patients who underwent colocolonic and colorectal anastomoses; 17% risk for spillage among
patients undergoing preparation, compared to 12% likelihood among those receiving no preparation; possible
explanation—bowel preparation liquefies intestinal waste, increasing chances of spillage
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| Ways to prevent or minimize intraoperative spillage of bowel contents: if bowel dilated or partially obstructed, insert
large-bore needle to decompress gas; remove some of waste around transection by milking it into area to be resected;
then occlude bowel proximal to waste in lumen; quarantine operative site; as bowel divided and manipulated, elevate it
above more proximal segment, so waste flows into more dependent portion; do not put suction catheter into lumen
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| Antibiotic prophylaxis: warranted for high-risk procedures or patients at high risk; should be directed against bacteria
known to be present; time administration so tissue concentrations highest during high-risk periods (eg, opening, closing);
administer first dose within 30 min of incision; readminister during surgery at intervals 1 to 2 times half-life of antibiotic
for duration of procedure (roughly q3h for colorectal surgery); postoperative administration not recommended; meta-
analysis of 147 trials of colorectal surgery showed no difference in rate of wound infections between single- and multiple-dose
therapy (administration of antibiotics postoperatively); conclusion—single-dose therapy preferred
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| Surgical Infection Prevention Project: developed by Centers for Medicare and Medicaid Services (CMS), to decrease
morbidity and mortality associated with surgical infections; supported by Joint Commission on Accreditation of
Healthcare Organizations (JCAHO); Medicare now financially penalizes hospitals that do not comply with mandatory
reporting requirements (“reporting for pay”); performance standards anticipated
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| Performance measures examined by JCAHO: administration of prophylactic agent 60 min before incision; use of agent
from roster of antibiotics chosen for narrow spectrum and safety; discontinuation of antibiotic <24 hr after conclusion
of operation
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| Roster of antibiotics: oral—neomycin-based, erythromycin-based, and neomycin-metronidazole; intravenous—cefotetan,
or cefoxitin (availability limited); cefazolin-metronidazole combination; ampicillin-sulbactam (Unasyn); if patient
penicillin-allergic or metronidazole-intolerant, substitute gentamicin or clindamycin; intraoperative dosing interval
q3h for all, except metronidazole (q6h); in Canadian meta-analysis of 13 randomized controlled trials, systemic therapy
alone associated with higher rate of surgical site infection, compared to oral and systemic administration combined;
however, subsequent study from Stanford University showed patients receiving combination more susceptible
to infection by Clostridium difficile
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| Other ways to lower risk for surgical site infection: maintain patient’s temperature during surgery; hypothermia
(core temperature <34.7°C) associated with higher incidence of infection; increased oxygen tension (higher fraction of
inspired oxygen [FiO2 ] associated with lower risk for infection)
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| NEW IMAGING TECHNIQUES —Dr. Strong
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| Evaluation of anal fistula: study of 104 patients with fistulae compared anal US with 10-mHz probe and magnetic resonance
imaging (MRI) to gold standard of examination under anesthesia; found that for primary tracts, US and MRI predicted
fistula anatomy better than clinical examination; MRI better than US at detecting horseshoe components; US and
MRI comparable for identifying internal openings; in another study, 3-dimensional US enhanced with hydrogen peroxide
agreed with MRI in detecting primary and secondary tracts and internal openings (little agreement over secondary circular
tracts); conclusion—hydrogen peroxide-enhanced, 3-dimensional US approaches MRI in accuracy, at lower expense
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| Preoperative staging of rectal cancer: in 2004 meta-analysis of ≈90 trials, little difference in sensitivity or specificity
between US and MRI; no significant advantage from new-generation MRI machines
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| Positron emission tomography (PET) and computed tomography (CT): PET alone important for evaluating patients with
suspected recurrence or metastasis of previously resected colorectal cancer; helpful in cases in which results from conventional
imaging inconclusive; also useful for thorough evaluation of recurrences that seem amenable to surgical resection
(PET may find undetected disease that renders patient unresectable); no good evidence of benefit for patients
with primary colorectal cancer; benefits of PET-CT combination—in study of 65 patients with rectal cancer with suspected
postoperative pelvic recurrences, PET-CT more accurate than PET alone; in different study of patients with primary
rectal cancer, PET alone before beginning therapy altered treatment plan in 17%; in another study, PET-CT
altered treatment plan in nearly 25% of patients with primary cancer; conclusion—PET alone or with CT helps in
evaluation of patients with primary rectal cancer
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| CT colonography: in meta-analysis comparing it to colonoscopy, sensitivity of colonography best with polyps >1 cm
(specificity high with lesions as small as 0.5 cm)
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| MR colonography: in meta-analysis comparing CT colonography, MR colonography, and colonoscopy, CT colonography
had greater sensitivity and comparable specificity, to MR colonography
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| Enterography: CT enterography used mostly in patients with Crohn’s disease; findings with MR enterography similar to
those of small-bowel follow-through; many clinicians now consider capsule endoscopy gold standard for imaging nonobstructing
lesions; in one study, only MR enterography yielded findings comparable to those of capsule endoscopy in
patients with Crohn’s disease
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Suggested Reading
Aggarwal R, Darzi A: Compression anastomoses revisited. J Am Coll Surg 201:965, 2005; Bozuk MI, et al: Use of
decellularized human skin to repair esophageal anastomotic leak in humans. JSLS 10: 83, 2006; Choy PY et al: Stapled
versus handsewn methods for ileocolic anastomoses. Cochrane Database Syst Rev CD004320, July 18, 2007; Fa-Si-Oen
P et al: Mechanical bowel preparation or not? Outcome of a multicenter, randomized trial in elective open colon surgery.
Dis Colon Rectum 48:1509, 2005; Fa-Si-Oen PR et al: Effect of mechanical bowel preparation with polyethyleneglycol
on bacterial contamination and wound infection in patients undergoing elective open colon surgery. Clin Microbiol Infect
11:158, 2005; Hara AK et al: Crohn disease of the small bowel: preliminary comparison among CT enterography, capsule
endoscopy, small-bowel follow-through, and ileoscopy. Radiology 238:128, 2006; Muller-Stich BP et al: Preoperative
bowel preparation: surgical standard or past? Dig Surg 23:375, 2006; Nicksa GA et al: Anastomotic leaks: what is
the best diagnostic imaging study? Dis Colon Rectum 50:197, 2007; Rowell KS et al: Use of national surgical quality
improvement program data as a catalyst for quality improvement. J Am Coll Surg 204: 1293, 2007; Sachdeva AK, Russell
TR: Safe introduction of new procedures and emerging technologies in surgery: education, credentialing, and privileging.
Surg Clin North Am 87: 853, 2007; Triester SL et al: A meta-analysis of the yield of capsule endoscopy
compared to other diagnostic modalities in patients with non-stricturing small bowel Crohn’s disease. Am J Gastroenterol
101:954, 2006; Wille-Jorgensen P et al: Pre-operative mechanical bowel cleansing or not? An updated meta-analysis.
Colorectal Dis 7: 304, 2005.
Educational Objectives
| The goals of this program are to review ethical and technical issues that must be considered when introducing new surgical
technologies, and to discuss new techniques in colorectal surgery and imaging. After hearing and assimilating this program,
the listener will be better able to:
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| 1. List issues to consider when bringing a new technology into practice.
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| 2. Discuss the role of evidence-based medicine in the introduction of new technologies into clinical practice.
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| 3. Describe ways to prevent or minimize anastomotic leaks.
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| 4. Explain why bowel preparation before gastrointestinal surgery is probably unnecessary.
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| 5. Identify the situations in which computed tomography colonography and magnetic resonance enterography have
shown the greatest benefit for colorectal surgery candidates.
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Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. The following has been disclosed:
Dr. Fleshman has received research funding from NiTi Medical Technologies and LifeCell.
Acknowledgements
Dr. Van Heerden spoke at the 2007 Annual Meeting of the Florida Chapter of the American College of Surgeons, held May
24-27, 2007, in Jacksonville, FL, and sponsored by the Florida Chapter of the American College of Surgeons; Drs. Fleshman
and Strong were recorded at 18th Annual International Colorectal Disease Symposium, held February 15-17, 2007, in
Fort Lauderdale, FL, and sponsored by the Cleveland Clinic Florida. The Audio-Digest Foundation thanks the speakers and
the sponsors for their cooperation in the production of this program.
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