Bread and Butter Surgery

From the 38th Annual Postgraduate Course in Surgery, sponsored by the Medical University of South Carolina, April 16-18, 2009

Educational Objectives

The goal of this program is to improve the prevention of surgical site infections and the management of complicated diverticular disease. After hearing and assimilating this program, the clinician will be better able to:

1.    Recognize evidence-based infection-prevention measures, such as hair removal, skin preparation with chlorhexidine, keeping the patient warm, and glucose control.

2.    Time the preoperative administration of prophylactic antibiotics for maximum benefit.

3.    Discuss the place of surgery in the management of diverticulitis.

4.    Describe the role of surgical management of diverticulitis in patients with serious comorbidities, such as colla­gen vascular diseases or renal transplantation.

5.   Review current treatments of perforated complicated diverticulitis.

Faculty Disclosure

In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and members of the planning committee to disclose relevant financial relationships within the past 12 months that might create any per­sonal conflicts of interest. Any identified conflicts were resolved to ensure that this educational activity promotes quality in health care and not a proprietary business or commercial interest. For this program, the following has been disclosed: Dr. Wolff is a consultant for Roche, Genzyme, and Tranzyme. Dr. Martindale and the planning committee reported nothing to disclose.

Ackowledgements

This program was recorded at the 38th Annual Postgraduate Course in Surgery, held April 16-18, 2009, in Charles­ton, SC, and sponsored by the Medical University of South Carolina. The Audio-Digest Foundation thanks the speak­ers and the Medical University of South Carolina for their cooperation in the production of this program.

Preventing Surgical Site Infection: Data or Dogma?

Robert G. Martindale, MD, PhD, Professor and Chief, Division of General Surgery, Oregon Health and Sci­ence University, Portland

Components of surgical infections: bacteria, wound environment, and host; 40% to 60% of surgical infections pre­ventable

Changing nature of surgical infections:  higher acuity of hospital care; higher incidence of organ failure; more fo­cus on rapid diagnosis; increasing incidence of Clostridium difficile; de-escalation of therapy (administering large doses of antibiotics very quickly, then de-escalating treatment very rapidly, often within 3 to 5 days); greater attention to prevention; alarming increase in resistant organisms; noncompliance with infection control measures (intensive care unit [ICU] staff often do not don gown or gloves before turning off alarms and tending to patients); patients often lack overt signs of infection

Resistant organisms: in addition to methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE), carbapenem-resistant Klebsiella pneumoniae (KPC) now proliferating, especially along northeastern coast

Preoperative precautions: hair removal  —  clipping better than shaving; clipping immediately before surgery “is the best way to go”; smoking cessation  —  study results mixed; in Danish study of patients voluntarily receiving 1-cm incisions over iliac crest, smoking cessation 1 mo before surgery lowered risk for infection from 12% to 2%; anti­septic shower  —“absolutely no data”; skin preparation in operating room  —duration of procedure is consideration; chlorhexidine kill activity persists 4 to 6 hr, compared to 30 to 60 min for povidone iodine (Betadine); open wound nullifies effect of iodine (binds to protein in wound, which inhibits its antimicrobial activity); chlorhexidine recom­mended; however, in large comparative study, infection risk slightly lower with povidone iodine than chlorhexi­dine; bowel preparation  —  associated with heightened infection risk in some studies; recent large study did not show increased infection risk, but showed no benefit with bowel preparation; antibiotic bowel preparation known to increase risk for C difficile infection; prophylactic antibiotics  —  timing of administration key; should be given within 1 hr of surgery; 5 to 10 min before surgery acceptable (takes ³4 min if skin adequately perfused and room warm; should allow ³10 min in chilly operating room); choice of antibiotics  —  first-generation cephalosporins ade­quate for noncolorectal surgery; colorectal surgery (from appendix to anus) requires more expanded coverage, eg, second-generation cephalosporins; single dose or 24-hr infusion makes no difference in infection rate; single dose usually sufficient; if surgical time long or patient loses >4 U of blood, consider redosing, depending on antibiotic’s half-life; prolonged prophylaxis (>48 hr) associated with higher risk for bacteremia and line infections or of having resistant flora

Perioperative precautions: intraoperative glucose control  —levels should be between 100 mg/dL and 150 mg/dL; at levels >200 mg/dL, infection rate rises exponentially; at speaker’s institution, preoperative hemoglobin A1c (Hb A_1c) measured for all diabetic patients; readings >8.0% indicate delay of elective surgery until glucose control im­proves; in recent study of 995 patients undergoing general and vascular surgery, rate of postoperative infections in­creased by 30% for every 40 mg/dL increase in blood glucose over 110 mg/dL; first 24 hr after surgery most important; antibiotic-impregnated sutures  —  no human data demonstrating decreased risk for infection; hypother­mia in operating room  —  causes vasoconstriction and associated with diminished T-cell function; no good evidence that bacteria cannot grow on cold surfaces; forced-air warming of patient associated with vasodilation, lower risk for infection, especially if procedure lasts >1 hr; supplemental oxygen during surgery and perioperatively  —  in pro­spective study of 500 patients receiving 80% fraction of inspired oxygen (FiO₂) or 30% FiO₂ intraoperatively and 2 hr postoperatively, rate of surgical site infections 5.2% and 11.2%, respectively (p=0.01); other studies produced similar results; risk for atelectasis low; antibiotic irrigation  —  no data support use; increases risk for adhesions in animal models; “clearly not evidence-based”; drains  —  use only when cavity present; skin adhesives  —  no data show decreased risk for infection in adults; continuous postoperative peritoneal lavage  —  no data on mortality; second-look surgery  —  helpful only in cases of ischemic bowel or possibly for source control

Postoperative precautions: ICU staffing  —  patient-to-nurse ratio >3:1 associated with significantly increased risk for ventilator-associated pneumonia; early enteral feeding  —virtually all studies show lower rate of C difficile in­fection associated with feeding within 48 hr;  recent meta-analysis (13 studies, 1100 patients) shows feeding within 24 hr of gastrointestinal surgery associated with lower mortality; probiotics  —  some good data support use; in re­cent randomized controlled study of 135 elderly patients on broad-spectrum antibiotics, those taking 200 mg Lacto­bacillus casei daily developed no C difficile infections; similar findings seen with VRE colonization

Miscellaneous precautions: surgical masks  —  no good data that they make difference in infection rates; surgical site barriers  —  in recent Cochrane meta-analysis, associated with higher, not lower, risk for infection; shoe covers  —associated with more pathogens on surgeons’ hands; single rooms in ICUs  —  “clearly decrease contamination”; scrubs leaving operating room  —  does not increase patients’ infection risk

Conclusion: use prophylaxis with first-generation cephalosporins, except for colorectal surgery (expanded spectrum indicated); other evidence-based anti-infection measures include warming, oxygenation, glucose control, and smoking cessation, if possible

Management of Complicated Diverticulitis

Bruce G. Wolff, MD, Professor of Surgery and Chair, Division of Colon and Rectal Surgery, Mayo Clinic Col­lege of Medicine, Rochester, MN

Types of diverticulitis: typical (relapsing, chronic, episodic); subacute (never resolves completely; “just keeps smol­dering”); complicated; and chronic (similar to subacute form, but with atypical symptoms; may be difficult to dis­tinguish from irritable bowel syndrome; may see atypical presentation by site, eg, hip abscess from sigmoid diverticulitis)

Current controversies: management of patients < 50 yr of age; whether to perform elective resection after percutane­ous drainage of abscess; elective resection after 2 episodes; Hartmann procedure vs primary anastomosis, espe­cially with perforation; laparoscopic surgery for complicated diverticulitis

Dietary limitations: in study of >47,000 men, “not a shred of evidence” that nuts, corn, or popcorn increased risk for diverticulosis or diverticular complications

Acute diverticulitis: initial episode  —  »20% require surgical intervention; »70% of patients who recover have no fu­ture symptoms; subsequent episodes  —  formerly considered progressive disease, with »60% of patients ulti­mately requiring surgical intervention; however, since 1970s, awareness has increased; antibiotics, critical care, and percutaneous drainage of abscesses added to management; recognition of irritable bowel syndrome has in­creased since 1980s; new imaging techniques, eg, computed tomography (CT), have improved diagnosis; surgi­cal management has evolved from 3 stages to 2 stages (Hartmann procedure) to primary anastomosis

Current management of uncomplicated diverticulitis: medically treated; »25% of patients experience recurrence, but <10% need surgery; any fatalities usually unrelated to diverticulitis; CT recommended to confirm diagnosis and for staging; in study including 196 patients <50 yr of age on medical management, only one (0.5%) devel­oped perforation during lengthy follow-up; conclusion  —selective individual management appropriate

Diverticular disease and collagen vascular disease: presence of disease such as lupus greatly increases risk for mortality over that associated with diverticular disease alone; risk for perforation also high; consider resection after first episode; anastomosis may be risky; best approach may be anastomosis with proximal loop ileostomy; immuno­compromised patients  —  also have higher than average mortality risk; diverticular disease may present atypically; maintain high index of suspicion; patients often young; immunosuppression may mask signs and symptoms; rate of free perforation increased; if renal transplantation patient complains of abdominal pain, get abdominal and pelvic CT with contrast; if diverticulitis diagnosed, stop all immunosuppression except steroids, and avoid nephrotoxic antibiotics; if perforation present, avoid primary resection with anastomosis; if patient taking steroids, vitamin A may help wound healing; at Mayo Clinic, one episode of diverticulitis in renal transplantation patient indicates elective resection

Complicated diverticulitis: mortality still relatively high; usually requires surgery; abscess  —  continued smoldering after drain placement suggests possible drain misplacement in small bowel; nonoperative management may be possible; if drainage resolves abscess, avoid elective resection (diverticulum that generated abscess probably al­ready destroyed); obstruction  —  be mindful of possible cancer; intraoperative colonic lavage — “an option, but it’s not perfect”; associated with risk for mortality and anastomotic leakage; stenting — valuable addition to sur­geon’s armamentarium; covered stent recommended to avoid tissue ingrowth (risk with uncovered stents); pa­tency rates good, but risk for migration high with uncovered stent; other complications include perforation and reobstruction, usually within 7 days; if using stent as bridge to surgery, perform surgery within 1 wk, if possible; all in all, stents effectively decompress high-grade benign obstruction; can convert emergent operation into elec­tive one, but associated with delayed complications; colovesical fistulae  —  surgery necessary; if cancer sus­pected, proceed and resect; hemorrhage  —resection depends on frequency, severity, localization, and patient condition; perforation  —  initial manifestation of diverticulitis in 70% of patients

Treatment of perforation: advantages of primary anastomosis  —  easy closure of diverting colostomy; completed colon resection; on-table lavage; reduced cost; advantages of Hartmann procedure  —  simpler to perform in emergency; requires less time on operating table (particularly valuable for unstable patient); disadvantages of primary anastomosis  —  longer, more extensive operation in emergency setting; not good if patient has heavy fe­cal load; massive distention means poor bowel circulation, including to anastomosis; concerns about performing in unstable patient; disadvantages of Hartmann procedure  —  hard reoperation; “almost always” have to resect more colon and take down splenic flexure; more than one-third of patients never get colostomy reversed; study of >16,000 patients showed significantly lower rate of in-hospital mortality or need for second stoma if reversal de­layed 6 mo after perforation

Relationship of previous episodes of perforation to development of complicated diverticulitis: in study conducted by speaker and colleagues of 330 patients, 30% developed abscess, 22% developed phlegmon, 22%, obstruc­tion, 13%, fistulae, and 4.5%, hemorrhage; 44.5% had perforation as manifestation of complicated diverticuli­tis; 41% of patients had cardiovascular comorbidities, 23% had pulmonary disease, and 22% were on steroids; 54% of patients had no history of diverticulitis (eg, first presentation was complicated diverticulitis); overall mortality rate 6.5% (22 patients); of those, 19 (86% of deaths) associated with perforation; 9% associated with anastomotic leak; 1 patient (4.5%) deemed too ill for surgery, treated nonoperatively; overall incidence of per­foration 44%, with mortality rate of 12%; abscess associated with mortality rate of 1%; no mortality associated with obstruction, phlegmon, fistulae, or bleeding; of patients with perforation who died, 90% had no history of diverticulitis; steroid use associated with increased risk for perforation and death; other risk factors for mortal­ity included diabetes, collagen vascular disease, and immune compromise; factors associated with morbidity were older age, perforation, preoperative comorbidity, steroids, and immune compromise

Conclusions: mortality from complicated diverticulitis reduced, compared to past data; perforation still associ­ated with significant mortality and morbidity; majority of patients overall and with perforation have no prior history of diverticulitis; prophylactic colectomy after 2 episodes of diverticulitis does not prevent complicated diverticular disease, nor its associated morbidity and mortality (colectomy after 2 episodes or one severe epi­sode may still be indicated to prevent future episodes and improve quality of life); immune- compromised pa­tients at particularly high risk and may benefit from early resection; prospective data needed but difficult to obtain

Laparoscopic peritoneal lavage for perforated diverticulitis: associated with promising findings in one small study (40 patients; 50% required interval sigmoid resection; no further treatment for other 50%)

Laparoscopic colectomy for complicated diverticulitis: included hand-assisted cases; morbidity slightly less among complicated than uncomplicated patients; median length of stay similar; uncomplicated patients had higher conversion rate; fast-track laparoscopic colectomy for diverticulitis “works, and it works well”

Suggested Reading

Baron TH: Colonic stenting: technique, technology, and outcomes for malignant and benign disease. Gastrointest En­dosc 15:757 2005; Chapman J et al: Complicated diverticulitis: is it time to rethink the rules? Ann Surg 242:576, 2005; Chura JC et al: Surgical site infections and supplemental perioperative oxygen in colorectal surgery patients: a system­atic review. Surg Infect (Larchmt) 8:455, 2007; Classen DC et al: The timing of prophylactic administration of antibiot­ics and the risk of surgical-wound infection. N Engl J Med 326:281, 1992; Greif R et al: Supplemental perioperative oxygen to reduce the incidence of surgical-wound infection. Outcomes Research Group. N Engl J Med 342:202, 2000; Guzzo J, Hyman N: Diverticulitis in young patients: is resection after a single attack always warranted? Dis Colon Rec­tum 47:1187, 2004; Hedrick TL et al: Single-institutional experience with the surgical infection prevention project in intra-abdominal surgery. Surg Infect (Larchmt) 8:425, 2007; Lewis SJ et al: Early enteral nutrition within 24 h of intes­tinal surgery versus later commencement of feeding: a systematic review and meta-analysis. J Gastrointest Surg 13:569, 2009; Pyrek Kelly M: Surgical Best Practices for Infection Prevention. Infection Control Today, posted February 27, 2009; Sorenson LT et al: Abstinence from smoking reduces incisional wound infection: a randomized controlled trial. Ann Surg 238:1, 2003; Strate L et al: Nut, corn and popcorn consumption and the incidence of diverticular disease. JAMA 300:907, 2008; Tanner J et al: Preoperative hair removal to reduce surgical site infection. Cochrane Database of Systematic Reviews 2:CD004122, 2006.