Anthony M. Vernava

Risk factors for morbidity and mortality after colectomy for colon cancer

PURPOSE: Comorbid conditions affect the risk of adverse outcomes after surgery, but the magnitude of risk has not previously been quantified using multivariate statistical methods and prospectively collected data. Identifying factors that predict results of surgical procedures would be valuable in assessing the quality of surgical care. This study was performed to define risk factors that predict adverse events after colectomy for cancer in Department of Veterans Affairs Medical Centers. METHODS: The National Veterans Affairs Surgical Quality Improvement Program contains prospectively collected and extensively validated data on more than 415,000 surgical operations. All patients undergoing colectomy for colon cancer from 1991 to 1995 who were registered in the National Veterans Affairs Surgical Quality Improvement Program database were selected for study. Independent variables examined included 68 preoperative and 12 intraoperative clinical risk factors; dependent variables were 21 specific adverse outcomes. Stepwise logistic regression analysis was used to construct models predicting the 30-day mortality rate and 30-day morbidity rates for each of the ten most frequent complications. RESULTS: A total of 5,853 patients were identified; 4,711 (80 percent) underwent resection and primary anastomosis. One or more complications were observed in 1,639 of 5,853 (28 percent) patients. Prolonged ileus (439/5,853; 7.5 percent), pneumonia (364/5,853; 6.2 percent), failure to wean from the ventilator (334/5,853; 5.7 percent), and urinary tract infection (292/5,853; 5 percent) were the most frequent complications. The 30-day mortality rate was 5.7 percent (335/5,853). For most complications, 30-day in-hospital mortality rates were significantly higher for patients with a complication than for those without. Thirty-day mortality rates exceeded 50 percent if postoperative coma, cardiac arrest, a pre-existing vascular graft prosthesis that failed after colectomy, renal failure, pulmonary embolism, or progressive renal insufficiency occurred. Preoperative factors that predicted a high risk of 30-day mortality included ascites, serum sodium >145 mg/dl, “do not resuscitate” status before surgery, American Society of Anesthesiologists classes III and IV OR V, and low serum albumin. CONCLUSIONS: Mortality rates after colectomy in Veterans Affairs hospitals are comparable with those reported in other large studies. Ascites, hypernatremia, do not resuscitate status before surgery, and American Society of Anesthesiologists classes III and IV OR V were strongly predictive of perioperative death. Clinical trials to decrease the complication rate after colectomy for colon cancer should focus on these risk factors.

Lower gastrointestinal bleeding

BACKGROUND: Lower gastrointestinal bleeding can be a confusing clinical conundrum, the satisfactory evaluation and management of which requires a disciplined and orderly approach. Diagnosis and management has evolved with the development of new technology such as selective mesenteric angiography and colonoscopy. PURPOSE: This study was undertaken to review the available data in the literature and to determine the current optimum method of evaluation and management of lower gastrointestinal hemorrhage most likely to result in a successful outcome. METHODS: Data available on the topic of lower gastrointestinal bleeding in the English literature were obtainedviaMEDLINE search and were reviewed and analyzed. RESULTS: The colonic origin of lower gastrointestinal hemorrhage in order of decreasing incidence is diverticulosis, inflammatory bowel disease, including ischemic and infectious colitis, colonic neoplasia, benign anorectal disease, and arteriovenous malformations. Approximately 10 to 15 percent of all cases of rectal bleeding are attributable to a cause that is proximal to the ligament of Treitz. Small intestinal sources such as arteriovenous malformations, diverticula, and neoplasia account for between 3 and 5 percent of all cases. Colonoscopy successfully identified an origin in severe hematochezia in 74 to 82 percent of cases. Mesenteric angiography has a sensitivity of 42 to 86 percent. The best method of management depends on whether hemorrhage persists, the severity of continued hemorrhage, the cumulative transfusion requirement, and the specific origin of bleeding. CONCLUSION: Lower gastrointestinal hemorrhage is a complex clinical problem that requires disciplined and sophisticated evaluation for successful management. Diverticulosis is the most common cause. Colonoscopy is the diagnostic procedure of choice both for its accuracy in localization and its therapeutic capability. Selective mesenteric angiography should be reserved for those patients in whom colonoscopy is not practical. Precise identification of the bleeding source is crucial for a successful outcome. Specific directed therapy, such as segmental colonic resection for bleeding diverticulosis, is associated with the highest success rate and the lowest morbidity. A complete review of lower gastrointestinal bleeding is contained herein.

Colonoscopic perforations. Etiology, diagnosis, and management.

Since its introduction into clinical medicine, flexible fiberoptic colonoscopy has had a great impact on diagnosis and management of diseases of the colon and rectum. There are three mechanisms responsible for colonoscopic perforation: specifically, mechanical perforation directly from the colonoscope or a biopsy forceps, barotrauma from overzealous air insufflation, and, finally, perforations that occur during therapeutic procedures. Perforation of the colon, which requires surgical intervention more frequently than bleeding, occurs in less than 1 percent of patients undergoing diagnostic colonoscopy and may be seen in up to 3 percent of patients undergoing therapeutic procedures such as polyp removal, dilation of strictures, or laser ablative procedures. Management of colonic perforation secondary to colonoscopy remains a controversial issue in that it can be effectively managed by operative and nonoperative measures. If a perforation does occur, signs and symptoms that the patient will experience will be related to both the size and site of the perforation, adequacy of the bowel preparation, amount of peritoneal soilage, underlying colonic pathology (where a thin walled colon from colitis or ischemia, for example, may result in a larger perforation than a healthy colon), and, finally, overall clinical condition of the patient. Radiology often establishes diagnosis. Plain films of the abdomen and an upright chest x-ray may reveal extravasated air confined to the bowel wall, free intraperitoneal air, retroperitoneal air, subcutaneous emphysema, or even a pneumothorax. A localized perforation may demonstrate lack of pneumoperitoneum. Some surgeons recommend surgery for all colonoscopic perforations; however, there does appear to be a role for conservative management in a select group of patients such as those with silent asymptomatic perforations and those with localized peritonitis without signs of sepsis that continue to improve clinically with conservative management. Finally, conservative management works well in those patients with postpolypectomy coagulation syndrome. Surgery is most definitely indicated in the presence of a large perforation demonstrated either colonoscopically or radiographically and in the setting of generalized peritonitis or ongoing sepsis. The presence of concomitant pathology at time of colonoscopic perforation such as a large sessile polyp likely to be a carcinoma, unremitting colitis, or perforation proximal to a nearly obstructing distal colonic lesion may force immediate surgery. Finally, in the patient who deteriorates with conservative management, one should proceed to surgery.

Clinical implications of jejunoileal diverticular disease

Congenital and acquired diverticula of the jejunum and ileum in the adult are unusual and occur in approximately 1 percent to 2 percent of the population. They are pulsion diverticula thought to be the result of intestinal dyskinesia. These lesions can produce a significant diagnostic and therapeutic dilemma. They are multiple in the jejunum and solitary distally and are characteristically found in 60- or 70-year-old males. The diagnosis may be confirmed with contrast studies of the small intestine, arteriography, or nuclear scan. Consider these disorders in patients with 1) unexplained gastrointestinal bleeding, 2) unexplained intestinal obstruction, 3) an unexpected cause of acute abdomen, 4) chronic abdominal pain, 5) anemia, or 6) malabsorption. Medical therapy is helpful in controlling diarrhea and anemia, while surgical therapy is reserved for hemorrhage, obstruction, perforation, or failure of medical management. Asymptomatic diverticula discovered on routine contrast studies need not be resected. At surgery, incidental diverticula should be removed when evidence of dilated, hypertrophied loops of small bowel with large diverticula is found. Intraoperative air distention will aid in diagnosis. Resection and primary anastomosis is the preferred treatment for non-Meckelian diverticula. Diverticulectomy is reserved for a Meckels diverticulum without evidence of ulceration. An incidental Meckels diverticulum should be removed in the presence of mesodiverticular bands or ectopic tissue. Removal of a Meckels diverticulum is not advised in the patient with Crohns disease but may be performed in the patient undergoing restorative proctocolectomy for ulcerative colitis.

Radical abdominopelvic lymphadenectomy : historic perspective and current role in the surgical management of rectal cancer

Radical abdominopelvic lymphadenectomy for rectal cancer is based on the tenet that removal of all potentially involved lymphatic tissue will yield a lower rate of locoregional failure and improve survival. At centers with extensive experience with the procedure, the operating time is only modestly prolonged compared with conventional resection. Blood loss and postoperative hospitalization are not significantly increased. Urinary dysfunction and impotence associated with radical abdominopelvic lymphadenectomy (as high as 80 percent and 76 percent, respectively, in recent series) have been major deterrents to its more routine application. Preservation of the hypogastric plexus and even selective preservation of a unilateral S4 nerve root have been shown to reduce the occurrence of genitourinary complications. Improved five-year survival of 68 percent and local recurrence rates of 5 to 20 percent for TNM Stage III cancers have been achieved with radical abdominopelvic lymphadenectomy. These results compare favorably with recent trials of adjuvant chemoradiation after conventional resection in stage-matched patients. The rationale, evolution, and application of radical abdominopelvic lymphadenectomy to the surgical management of rectal cancer are critically examined. The potential benefits of radical abdominopelvic lymphadenectomy, which have been demonstrated in nonrandomized trials, should be evaluated in a prospective and properly randomized study to clearly establish or refute its efficacy.

Outcome after proctectomy for rectal cancer in Department of Veterans Affairs Hospitals: a report from the National Surgical Quality Improvement Program.

OBJECTIVE To define risk factors that predict adverse outcomes after proctectomy for cancer in Department of Veterans Affairs Medical Centers. SUMMARY BACKGROUND DATA Accurate presurgical assessment of the risk of perioperative complications and death is important in planning surgical therapy. METHODS The National VA Surgical Quality Improvement Program contains prospectively collected and extensively validated data on >287,000 patients. All patients undergoing proctectomy for rectal cancer from 1991 to 1995 who were registered in this data base were selected for study. Independent variables examined included 68 presurgical and 12 intraoperative clinical risk factors; dependent variables were 21 specific adverse outcomes. Stepwise logistic regression analysis was used to construct models predicting 30-day morbidity rates for each of the 10 most common complications and the 30-day mortality rate. RESULTS Five hundred ninety-one patients were identified; 467 (79%) underwent abdominoperineal resection and 124 (21%) were treated with sphincter-saving procedures. Thirty percent of patients had one or more complications after proctectomy. Prolonged ileus, urinary tract infection, pneumonia, and deep wound infection were the most frequently reported complications. The 30-day mortality rate was 3.2% (19 deaths). For most complications, 30-day mortality rates were significantly higher for patients with complications than for those without. Thirty-day mortality rates for several complications exceeded 50%: cardiac arrest requiring cardiopulmonary resuscitation, deep venous thrombosis or thrombophlebitis, coma lasting >24 hours, acute renal failure, cerebrovascular accident, and pulmonary embolism. Four presurgical factors predicted a high risk of 30-day mortality in the logistic regression analysis: elevated blood urea nitrogen level, impaired sensorium, low serum albumin concentration, and partial thromboplastin time < or =25 seconds. CONCLUSIONS Mortality rates after proctectomy in VA hospitals are comparable to those reported in other large series. Most postsurgical complications are associated with an increased 30-day mortality rate. Elevated presurgical blood urea nitrogen level, impaired sensorium, low serum albumin concentration, and partial thromboplastin time < or =25 seconds predict a high risk of 30-day mortality.

Chronic constipation—Is the work-up worth the cost?

BACKGROUND: Chronic constipation can be a disabling condition that may require colectomy. Evaluation has been included as a way to select appropriate patients for colectomy and may also be extensive, unrevealing, and costly. AIMS: This study was undertaken to determine the cost and use of evaluation and outcome of patients with chronic constipation. METHODS: Patients with chronic constipation were reviewed for severity of symptoms, diagnostic studies performed, treatment, and outcome. The costs of the diagnostic studies were determined at our institution. Fifty-one patients were identified with chronic constipation; all were referred by other physicians. Mean age was 54 (range, 21–81) years; 59 percent were females. Average number of bowel movements per week was two (range, 0–4), and average duration of symptoms was five years (range, 1–20). Forty-three of 51 (84 percent) colonoscopies or barium enemas were normal. Thirteen of 51 (25 percent) colonic transit studies were abnormal. Twenty-six of 51 (51 percent) patients underwent defecography; 12 (46 percent) were abnormal. Thirty-seven of 51 (74 percent) underwent anal manometry; 5 (14 percent) were abnormal. One of 18 (6 percent) rectal biopsies demonstrated Hirschsprungs disease. Overall, 8 patients (16 percent) were diagnosed with outlet obstruction, 12 (24 percent) with colonic inertia, and 31 (61 percent) with constipation of unclear etiology. Overall mean cost of diagnosis was

Recurrent squamous cell carcinoma of the anal canal : predictors of initial treatment failure and results of salvage therapy

2,752 (range,

Prokinetic agents for lower gastrointestinal motility disorders

1,150–

Histologic analysis of the irradiated anal sphincter

4,792). Fiber, cathartics, or biofeedback therapy was successful in 33 of 51 (65 percent) patients. Among the remaining 18 patients, 12 underwent surgery, of which 10 were successful. The remaining eight patients were constipated, despite treatment. CONCLUSION: A cost of