Optimal testing parameters for blood cultures

The effects of volume of blood, number of consecutive cultures, and incubation time on pathogen recovery were evaluated for 37,568 blood cultures tested with the automated BACTEC 9240 instrument (Becton Dickinson Diagnostic Instrument Systems) at a tertiary care center over the period of 12 June 1996 through 12 October 1997. When the results for this study were compared with previous data published for manual broth-based blood culture systems and patient samples obtained in the 1970s and 1980s, the following were found: (1) the percentage increase in pathogen recovery per milliliter of blood is less, (2) more consecutive blood culture sets over a 24-h period are required to detect bloodstream pathogens, and (3) a shorter duration of incubation is required to diagnose bloodstream infections. Guidelines developed in the 1970s and 1980s for processing and culturing blood may require revision.

Detection of herpes simplex virus DNA in genital and dermal specimens by LightCycler PCR after extraction using the IsoQuick, MagNA Pure, and BioRobot 9604 methods

We evaluated two automated systems, MagNA Pure (Roche Molecular Biochemicals, Indianapolis, Ind.) and BioRobot 9604 (Qiagen, Inc., Chatsworth, Calif.) as effective replacements for the manual IsoQuick method (Orca Research, Inc., Bothell, Wash.) for extraction of herpes simplex virus (HSV) DNA from dermal and genital tract specimens prior to analysis by LightCycler PCR. Of 198 specimens (152 genital, 46 dermal), 92 (46.2%) were positive for HSV DNA by LightCycler PCR after automated extraction of specimens with either the MagNA Pure or BioRobot 9604 instrument. The manual IsoQuick method yielded HSV DNA (total n = 95) from three additional specimens that were negative by the automated method (P = 0.25, sign test). Although the mean numbers of LightCycler PCR cycles required to reach positivity differed statistically significantly among all three of the methods of extraction, the estimated means differed by no more than 1.5 cycles (P < 0.05). Seventy (76%) of the 92 specimens that were LightCycler PCR positive by all three extraction methods were also positive by shell vial cell culture assay. HSV DNA was detected by a lower LightCycler PCR cycle number (26.1 cycles) in specimens culture positive for the virus than in culture-negative samples (33.3 cycles) (P < 0.0001). The manual IsoQuick and automated MagNA Pure and BioRobot 9604 methods provide standardized, reproducible extraction of HSV DNA for LightCycler PCR. The decision to implement a manual versus an automated procedure depends on factors such as costs related to the number of specimens processed rather than on the minimal differences in the technical efficiency of extraction of nucleic acids among these methods.

Characteristics and evolution of extraintestinal manifestations associated with ulcerative colitis after proctocolectomy

AIMS

Describe the characteristics of extraintestinal manifestations complicating ulcerative colitis present preoperatively and determine their evolution after surgery.

METHODS

Between 1976 and 1986, 281 patients with ulcerative colitis exhibiting one or more extraintestinal manifestations (EIM) before either IPAA (n = 147), Brooke ileostomy (n = 71), Kock pouch (n = 48) or ileorectostomy (n = 15) were assessed retrospectively. The clinical evolution of each manifestation was classified as having disappeared, improved, remained unchanged or aggravated postoperatively. An efficacy index was designed to assess the ratio of the number of cases cured or improved over the number of cases unchanged or aggravated. The relationship between EIM and gender, age, duration of disease and the type of surgery was also ascertained.

RESULTS

433 EIM were observed in 281 patients. The most common were arthralgias of the large joints (n = 146), of the sacroiliac joint (n = 59) and the small joints (n = 51). In comparison to patients without EIM having received the same operation during the same period of time, EIM were seen more often in women, younger patients, than those with longer duration of disease and the ileoanal anastomosis group. 60% had only one EIM at a time. Based on the efficacy index, thromboembolic accidents and erythema nodosum were the most commonly cured or improved. Ocular manifestations and primary sclerosing cholangitis were unaffected. The other EIM responded favorably but variably with improvement in two thirds of patients. The presence of a rectal remnant (IRA) or ileal reservoir did not affect the evolution of the EIM.

CONCLUSIONS

Thromboembolic complications which are life-threatening, erythema nodosum and arthralgia of the small and large joints which impair quality of life, benefited the most from proctocolectomy. Those conditions may be considered preoperatively when making the decision for surgery.

Laparoscopic ultrasonography: a training model

PURPOSE

The purpose of this study was to develop a surgical training program and to test the accuracy of laparoscopic ultrasound in detecting injected lesions in pig livers.

METHODS

Pig livers were divided into eight segments and injected with Surgilube "malignant" and silicone "benign" lesions. All were examined by laparoscopic ultrasound followed by liver explantation to confirm results. First, a pilot study was conducted on six swine by injecting Surgilube lesions and performing laparoscopic ultrasound through 3 different ports (left upper quadrant (I), umbilicus (II), and right lower quadrant (III)) to determine per-segment accuracy and to optimize port placement. Second, blinded injection of Surgilube and silicone implants was done on 18 pigs with laparoscopic ultrasound conducted through the two most accurate ports from the pilot study. This model was then tested during a resident training workshop.

RESULTS

In the pilot study, per-lesion and per-segment sensitivity was 96 percent, with no difference among the three ports used. Ports I and II were chosen for the blinded study for their convenience in performing laparoscopic colectomy. In the blinded study, per-segment sensitivity, specificity, and accuracy were 97 percent, 94 percent, and 96 percent and 99 percent, 94 percent, and 97 percent for ports I and II, respectively. At the conclusion of a pilot workshop, trainee per-segment sensitivity, specificity, and accuracy were 60 percent, 80 percent, and 70 percent, respectively. The major difficulty was differentiating benign from malignant lesions.

CONCLUSIONS

A useful liver laparoscopic ultrasound training model for surgeons was developed with good preliminary results. It is anticipated that further training will enhance laparoscopic ultrasound accuracy rates before application of this modality in humans.

A prospective randomized comparison of laparoscopic appendectomy with open appendectomy: Clinical and economic analyses

BACKGROUND

Previous randomized studies of laparoscopic appendectomy produced conflicting recommendations, and the adequacy of sample sizes is generally unknown. We compared clinical and economic outcomes after laparoscopic and open appendectomy in a sample of predetermined statistical power.

METHODS

A pre-study power analysis suggested that 200 randomized patients would yield 80% power to show a mean decrease of 1.3 days' hospitalization. One hundred ninety-eight patients with a preoperative diagnosis of acute appendicitis were randomized prospectively to laparoscopic or open appendectomy. Economic analysis included billed charges, total costs, direct costs, and indirect costs associated with treatment.

RESULTS

Laparoscopic appendectomy took longer to perform than open appendectomy (median, 107 vs 91 minutes; P <.01) and was associated with fewer days to return to a general diet (mean, 1.6 versus 2.3 days; P <.01), a shorter duration of parenteral analgesia (mean, 1.6 versus 2.2 days; P <.01), fewer morphine-equivalent milligrams of parenteral narcotic (median, 14 mg versus 34 mg; P =.001), a shorter postoperative hospital stay (mean, 2.6 versus 3.4 days; P <.01), and earlier return to full activity (median, 14 versus 21 days; P <.02). However, operative morbidity and time to return to work were comparable. Billed charges and direct costs were not significantly different in the 2 groups ($7711 versus $7146 and $5357 versus $4945, respectively), but total costs (including indirect costs) of laparoscopic appendectomy were, on average, nearly $2400 less, given the shorter length of stay and abbreviated recuperative period ($11,577 versus $13,965). Subgroup analyses suggested the benefit of a laparoscopic approach for uncomplicated appendicitis and for patients with active lifestyles.

CONCLUSIONS

While laparoscopic appendectomy is associated with statistically significant but clinically questionable advantages over open appendectomy, a laparoscopic approach is relatively less expensive. The estimated difference in total costs of treatment (direct and indirect costs) was at least $2000 in more than 60% of the bootstrapped iterations. The economic significance and implications favoring a laparoscopic approach cannot be ignored.

Physeal fractures: Part 1. Epidemiology in Olmsted County, Minnesota, 1979-1988

All children in Olmsted County, Minnesota, who had a physeal fracture in the 10-year period 1979 through 1988 were identified in this population based study. Children with acute fractures from surrounding areas of Olmsted County and children with subacute, chronic fractures or complications of fractures among referral patients were not included. Eight-hundred fifty children sustained 951 physeal fractures; 561 boys (66%) sustained 637 fractures, and 289 girls (34%) experienced 314 fractures. The male:female ratio was 2:1 and incidence rates were greatest among 11-12 year-old girls and 14-year-old boys. The overall age- and sex-adjusted incidence of physeal fractures was 279.2 per 100,000 person-years (95% confidence interval, 261.4-296.9). The most common site was the phalanges of fingers, which accounted for 37% of all physeal fractures. Salter-Harris type II was the most common type of fracture (54%), but 149 fractures (16%) did not fit into this classification. Therefore, two new, previously unclassified fracture types were added and are reported in detail (see Physeal Fractures: Part 2. Two Previously Unclassified Types, pp. 431-38). This led to a review of existing classifications and creation of a new one (see Physeal Fractures: Part 3. Classification, pp. 439-48).

Leiomyosarcoma of the rectum and anus. A series of 22 cases

Twenty-two patients with leiomyosarcoma of the rectum (n = 19) or the anus (n = 3) were treated surgically at the Mayo Clinic from 1950 through 1985. The majority of tumors occurred in men (1.4:1.0) during the sixth and seventh decades of life. Fifty-nine percent of the patients had symptoms including, most commonly, change in bowel habit, bleeding, and pain. Wide local excision was performed in 10 patients, whereas a more radical surgical procedure, including abdominoperineal resection (n = 8), pelvic exenteration (n = 2), and low anterior resection (n = 1), were performed in 11 patients. One tumor was unresectable. The overall survival until death from disease was 90% at 1 year, 74% at 5 years, and 51% at 10 years postoperatively. The percentage of patients free of disease at 1, 5, and 10 years postoperatively was 85, 62, and 40, respectively. Wide local resection was not superior to a more radical surgical approach in preventing tumor recurrence or improving survival. Lesions less than 2.5 cm and confined to the bowel wall can be treated by wide local excision, whereas larger or more extensive tumors should be treated by a more radical surgical approach.

Surgical repair of chronic rotator cuff tears. A prospective long-term study

BACKGROUND

Rotator cuff disease or injury is one of the most frequently seen orthopaedic conditions, and surgical repair of rotator cuff tears is a common procedure. A prospective analysis of the operation, with consistent assessment of patient characteristics, variables associated with the rotator cuff tear and repair techniques, and outcome factors, was performed.

METHODS

One hundred and five shoulders with a chronic rotator cuff tear underwent open surgical repair and acromioplasty between 1975 and 1983. The patients were followed for an average of 13.4 years (range, two to twenty-two years). There were sixteen small tears, forty medium tears, thirty-eight large tears, and eleven massive tears. The tears were repaired directly (seventy-two tears), by V-Y plasty (twelve), by tendon transposition (twenty), or by reinforcement with a fascia lata graft (one). The long head of the biceps had been previously torn in eleven shoulders and was tenodesed in three other shoulders. In fifty-six shoulders, the distal part of the clavicle was excised for treatment of degenerative arthritic changes, often associated with osteophyte formation.

RESULTS

Satisfactory pain relief was obtained in ninety-six shoulders (p < 0.0001). There was significant improvement in active abduction (p < 0.001) and external rotation (p < 0.007) as well as in strength in these directions of movement (p < 0.03 and p < 0.002, respectively). At the latest follow-up evaluation, the result was rated as excellent for sixty-eight shoulders, satisfactory for sixteen, and unsatisfactory for twenty-one. Tear size was the most important determinant of outcome with regard to active motion, strength, rating of the result, patient satisfaction, and need for a reoperation. Older age, less preoperative active motion, preoperative weakness, distal clavicular excision, and a transposition repair technique were all associated with larger tear size. There were eight reoperations; five were for rerepair of a persistent or recurrent rotator cuff tear.

CONCLUSIONS

Standard tendon repair techniques combined with anterior acromioplasty, postoperative limb protection, and monitored physiotherapy can produce consistent and lasting pain relief and improvement in range of motion. Improving the results of this procedure will depend upon the development of new techniques to address the active motion and strength deficiencies following repair of massive rotator cuff tears.

Trauma in pregnancy

OBJECTIVE

To determine whether the severity of maternal injury or other maternal and fetal variables will predict the outcome of pregnancy in the injured pregnant patient.

PATIENTS AND METHODS

In this retrospective review of pregnant patients hospitalized at a level 1 trauma center from 1986 to 1996, we analyzed the maternal Injury Severity Score, maternal mortality, fetal-neonatal mortality, maternal hypotension, and fetal heart rate.

RESULTS

Sixty-one pregnant women were identified who were hospitalized after trauma. The mean +/- SD maternal age was 26.6 +/- 6.6 years. The distribution of trauma per gestational age was 21%, 20%, and 59% for the first, second, and third trimester, respectively. The most common mechanism of injury was motor vehicle crashes. Long-term pregnancy outcome was available in 53 patients (87%). There was 1 maternal death. Fetal-neonatal death occurred in 8 (15%) of 53 pregnancies. Most maternal physiologic variables were not predictors of pregnancy outcome. We were unable to detect a difference in the distribution of Injury Severity Scores between viable and nonviable pregnancies. However, maternal hypotension and low fetal heart rate were common in nonviable pregnancies (P = .02).

CONCLUSIONS

Maternal hypotension and fetal heart rate are potential predictors of pregnancy outcome after trauma. Other maternal and fetal physiologic variables are poor measures of fetal well-being and are unable to predict fetal outcome. Fetal-neonatal death does not necessarily correlate with severity of maternal injury.

Gastrointestinal carcinoid tumors: long-term prognosis for surgically treated patients

To evaluate long-term survival of patients with gastrointestinal carcinoid tumors and to assess factors that may influence prognosis, 154 patients (49% females, 51% males), median age 62 years (range 12-84 years) treated at our institution during 1972-1982 have been followed long term. Tumor location included the foregut (7%), midgut (62%), and hindgut (30%). Ninety-five percent of the patients underwent surgical or endoscopic excision of the primary tumor, with overall operative mortality and postoperative morbidity rates of 2. 6% and 11%, respectively. At follow-up, 60 patients (39%) were alive (median follow-up 18 years; range 1-26 years). The main causes of death included carcinoid tumor burden (32%), unrelated causes (45%), other malignancy (19%), and unknown causes (4%). Observed overall 5- and 10-year survivals were 69% and 53%, respectively. Survival was not related to gender or symptoms at presentation. However, age, embryologic origin, tumor size, depth of invasion, nodal status, and stage of disease proved to be of statistical significance (log-rank). In a multivariate Cox' model, only older age (> 62 years) [P = 0. 001, odds ratio (OR) = 3.4) and embryologic origin (midgut versus foregut) (P = 0.045, OR = 0.45) provided independent prognostic power when death from any cause was taken as the end-point. This study confirms that patient's age and the site of the primary tumor have prognostic significance. Carcinoid tumors are neuroendocrine tumors with a relatively good prognosis, and long-term survival is possible despite advanced stages of disease.

Redefined duplex ultrasonographic criteria for diagnosis of carotid artery stenosis

OBJECTIVE

To evaluate duplex ultrasonographic criteria for the determination of 50% or more and 70% or more stenosis of the diameter of the internal carotid artery based on conventional angiography in order to align ultrasonographic diagnostic categories with current clinical management schemes.

PATIENTS AND METHODS

Between January 1, 1995, and June 30, 1999, 915 patients underwent both carotid duplex ultrasonography and cerebral angiography within 30 days at Mayo Clinic, Rochester, Minn. Of these patients, 294 were excluded from this study because of occlusion of one or both of the internal carotid arteries or atypical flow characteristics. In the remaining 621 patients (61 % male, 39% female; mean age, 67.7 years [range, 14-88 years]), 1218 vessels were available for correlation. Several Doppler ultrasonographic velocity variables were compared with the angiographic findings by use of receiver operating characteristic curve analysis. The primary end point was verification of optimal ultrasonographic criteria to diagnose 70% or more internal carotid artery stenosis. The secondary end point was establishment of threshold values to detect stenosis of 50% or more.

RESULTS

At angiography, 382 patients had internal carotid arteries with 70% or more stenosis. Peak systolic and end diastolic velocities of the internal carotid artery and internal carotid artery:common carotid artery peak systolic velocity ratios were measured. For an internal carotid artery stenosis of 70% or more, a peak systolic velocity of 230 cm/s or more resulted in a sensitivity of 86.4%, a specificity of 90.1%, a positive predictive value of 82.7%, a negative predictive value of 92.3%, and an accuracy of 88.8%. An end diastolic velocity of 70 cm/s or more and an internal carotid artery:common carotid artery ratio of 3.2 or more yielded similar values. For an internal carotid artery stenosis of 50% or more, a peak systolic velocity of 130 cm/s or more resulted in a sensitivity of 92.1 %, a specificity of 89.5%, a positive predictive value of 90.3%, a negative predictive value of 91.3%, and an overall accuracy of 90.8%. An internal carotid artery:common carotid artery ratio of 1.6 or more yielded similar values.

CONCLUSION

In our ultrasonography laboratory, a carotid artery stenosis of 70% or more (for which carotid endarterectomy is typically recommended in symptomatic patients) is diagnosed reliably with the following duplex ultrasonographic criteria: a peak systolic velocity of 230 cm/s or more, an end diastolic velocity of 70 cm/s or more, or an internal carotid artery:common carotid artery ratio of 3.2 or more.

Are patients with multiple endocrine neoplasia type I prone to premature death?

Multiple endocrine neoplasia type I (MEN-I) is an autosomal dominant disorder characterized by endocrinopathies involving the anterior pituitary gland, parathyroid glands, and pancreas. The long-term prognosis for patients affected with this disorder is uncertain. To better characterize this prognosis, we performed a retrospective review of all patients with MEN-I treated at a single institution during the period 1951-1997. A group of 233 patients served as the study population. Their records were analyzed for confirmation of diagnosis, treatments received, long-term survival, and cause of death. Altogether, 108 eight male patients (46%) and 125 female patients (54%) were identified. At the conclusion of the study, 164 (70%) were alive and 69 (30%) were deceased, with a median follow-up for patients alive at last contact of 13.4 years (range < 1 month to 54.3 years). The cause of death was reliably obtained in 60 patients. Of these patients, 17 (28%) died of causes related to MEN-I, most commonly metastatic islet cell tumors (10 patients). The remaining patients died of causes unrelated to MEN-I, most commonly coronary artery disease and nonendocrine malignancies (14% each). The overall 20-year survival of MEN-I patients was 64% (95% CI was 56-72%), and that of an age- and gender-matched upper Midwest population was 81% (p < 0.001). Patients with MEN-I appear to be at increased risk of premature death. Earlier diagnosis and treatment of potentially malignant pancreatic islet cell neoplasms may result in a decrease of this premature mortality.

Change in diagnosis among orthopedists compared to non-orthopedists in the management of acute knee injuries

OBJECTIVE

Uncertainty regarding diagnosis is associated with lower patient satisfaction and can lead to delays in definitive treatment and to inappropriate use of resources. We sought to compare change in diagnosis among orthopedists and non-orthopedists caring for a community based cohort of individuals with incident acute knee injuries.

METHODS

We conducted a longitudinal investigation of a population based cohort of Olmsted County residents with their first episode of acute knee injury occurring between January 1, 1993, and December 31, 1995. We reviewed the entire (inpatient and outpatient) medical records for these patients and collected extensive clinical data on all diagnoses made (including possible and probable) and the specialty of the attending physician(s) making them. Diagnoses were categorized as: (1) meniscus injury, cruciate injury, or osteochondral fracture; (2) ligament injury, patellar instability, patellar injury; or (3) sprain, strain, injury (unspecified). Diagnostic switches were defined as changes from one diagnostic category to another, or the addition or subtraction of a diagnostic category. We then examined the quality of the documented evidence supporting meniscal, ligamentous, and cruciate diagnoses (at initial evaluation) by comparing the clinical evidence to the recommendations outlined by the American Academy of Orthopaedic Surgeons clinical algorithm on acute knee injury. Analyses were conducted comparing (1) the number of diagnostic switches and (2) the quality of the documented evidence among those cases initially cared for by orthopedists and those cared for by non-orthopedists, using logistic regression analysis adjusting for age, sex, and injury severity. The influence of these variables on costs of care was also examined.

RESULTS

There were 664 patients (361 men and 303 women) in our study population, with an average age of 36.0 years (minimum 17, maximum 87). Of these, 324 were excluded because they only had one clinical encounter for their acute knee injury. Of the remaining 340, 59 (17.4%) were initially cared for by an orthopedist and 211 (62.1%) were cared for by an orthopedist at some time during their care. Diagnostic switches were significantly less frequent in the group who were cared for by orthopedists (55% vs 74%, p < 0.001). This result persisted after adjusting for age, sex, and severity (p = 0.003). The proportion of cases whose diagnoses were supported by evidence was significantly higher among the group whose first attending physician was an orthopedist (63.0% vs 37.6%, p = 0.002). Both change in diagnosis (p < 0.001) and physician specialty (p < 0.001) were statistically significant predictors of costs of care.

CONCLUSION

Compared to non-orthopedic care, orthopedic care for acute knee injury was associated with fewer changes in diagnosis, and diagnoses made by orthopedists were more likely to be supported by evidence. However, even after adjusting for severity, orthopedic care remained significantly more costly than non-orthopedic care.

Effects of 4 hand-drying methods for removing bacteria from washed hands: a randomized trial

OBJECTIVE

To evaluate the effects of 4 different drying methods to remove bacteria from washed hands.

SUBJECTS AND METHODS

One hundred adult volunteers participated in this randomized prospective study. All bacterial counts were determined using a modified glove-juice sampling procedure. The difference was determined between the amounts of bacteria on hands artificially contaminated with the bacterium Micrococcus luteus before washing with a nonantibacterial soap and after drying by 4 different methods (cloth towels accessed by a rotary dispenser, paper towels from a stack on the hand-washing sink, warm forced air from a mechanical hand-activated dryer, and spontaneous room air evaporation). The results were analyzed using a nonparametric analysis (the Friedman test). By this method, changes in bacterial colony-forming unit values for each drying method were ranked for each subject.

RESULTS

The results for 99 subjects were evaluable. No statistically significant differences were noted in the numbers of colony-forming units for each drying method (P = .72).

CONCLUSION

These data demonstrate no statistically significant differences in the efficiency of 4 different hand-drying methods for removing bacteria from washed hands.

Intraoperative topical tetracycline sclerotherapy following mastectomy: a prospective, randomized trial

BACKGROUND AND OBJECTIVES

Postoperative wound seromas are a frequent and troublesome occurrence after mastectomy. Recent reports have suggested the efficacy of topical sclerosants at reducing their formation.

METHODS

A prospective, randomized, double-blinded trial was performed to examine the effect of intraoperatively administered topical tetracycline on the occurrence of postoperative mastectomy seromas. Thirty-two women were randomized to the control arm (normal saline) and 30 women to the tetracycline arm. In the treatment group, 100 ml (2 g) of tetracycline solution was administered topically to the chest wall and skin flaps prior to skin closure. The control group received an equal volume of normal saline. Patients were monitored for the development of postoperative wound seroma.

RESULTS

There were no significant differences between groups regarding total volume of closed suction drainage, numbers of patients leaving hospital with drains in place, or duration of catheter drainage. Seroma formation 2 weeks postoperatively was greater in the tetracycline group than the control group (53% vs. 22%, P = 0.01). There were no differences between groups regarding the degree of postoperative pain, wound infection, or seroma formation 1 month postoperatively.

CONCLUSIONS

Topical tetracycline is not effective at preventing post-mastectomy wound seromas.

Physiologic responses to laparoscopic aortofemoral bypass grafting in an animal model

OBJECTIVE

To measure and compare the physiologic, metabolic, and hemodynamic responses to aortofemoral bypass grafting by three techniques: open or conventional laparotomy, laparoscopic-assisted (minilaparotomy), and totally laparoscopic grafting.

METHODS

Twenty-four laboratory-bred hounds were randomized to one of three groups (open, laparoscopic-assisted, or totally laparoscopic). Four sets of parameters were measured: hemodynamic (intraoperative continuous cardiac output monitoring), inflammatory or hematologic (serial leukocyte and platelet levels), metabolic responses (serial blood glucose, serum cortisol and insulin, plasma epinephrine, plasma norepinephrine, and dopamine levels), and catabolic (24-hour urinary nitrogen excretion).

RESULTS

Cardiac output increased transiently with aortic cross-clamping, more in the laparoscopic-assisted and total laparoscopic groups than in the open group, but the differences were not significant. White blood counts nearly doubled within 12 hours of surgery but were similar in all three groups. Platelet counts decreased significantly in all three groups, but no significant intergroup effects were observed. Metabolic parameters (e.g., blood glucose, cortisol, and catecholamine) rose significantly during surgery but fell to normal within 24 hours, with no important difference between groups. For the first 24 hours, urinary urea excretion fell by 50% but returned to normal by 7 days in all three groups.

CONCLUSIONS

In the experimental animal model, the hemodynamic, hematologic, and metabolic responses to laparoscopic and laparoscopic-assisted aortofemoral bypass grafting are similar to those produced by conventional laparotomy graft placement. These data call into question whether laparoscopic techniques for aortic surgery have a significant physiologic advantage in humans.

Safety and advantages of laparoscopic vs. open colectomy in the elderly: matched-control study

PURPOSE

The aim of this study was to determine rates of complications and extent of benefits for laparoscopic-assisted colectomy compared with open colectomy in patients older than age 75.

METHODS

Forty-two patients undergoing laparoscopic-assisted colectomy (1992-1998) were matched to 42 open colectomy patients for gender, age, year of surgery, operating surgeon, and procedure. Health status (American Society of Anesthesiology score), previous abdominal surgery, conversion rate, surgical outcome, and need for assistance at admission and dismissal (independence vs. home with assistance vs. nursing facilities) were reviewed.

RESULTS

Mean ages were 81.2 and 80.5 years for laparoscopic-assisted colectomy and open colectomy, respectively (P = not significant). Twenty-one laparoscopic-assisted colectomy and 23 open colectomy patients were females. American Society of Anesthesiology scores were comparable, as were rates of previous abdominal surgery (57 percent for laparoscopic-assisted colectomy vs. 62 percent for open colectomy; P = not significant). Mean operative times were longer for laparoscopic-assisted colectomy (190 minutes for laparoscopic-assisted colectomy vs. 142 minutes for open colectomy; P < 0.001); operating room times progressively decreased from 221 minutes in 1992 to 1995 to 147 in 1998 for laparoscopic right hemicolectomy (P < 0.001). The conversion rate for laparoscopic-assisted colectomy was 14.3 percent. There were no deaths in either group, and laparoscopic-assisted colectomy was associated with fewer morbidities (14.3 percent for laparoscopic-assisted colectomy vs. 33.3 percent for open colectomy; P = 0.04), narcotic usage (2.7 vs. 4.8 days; P < 0.001), time to return to bowel movements (3.9 vs. 5.9 days; P < 0.001), and length of hospital stay (6.5 vs. 10.2 days; P < 0.001). Independent status at admission in 37 laparoscopic-assisted colectomy and 38 open colectomy patients was maintained at discharge by 35 laparoscopic-assisted colectomy vs. 29 open colectomy patients (P = 0.025).

CONCLUSIONS

Laparoscopic-assisted colectomy is safe and beneficial, including preservation of postoperative independence, to the elderly when compared with open colectomy.

Long-term outcomes for surgically resected craniopharyngiomas

OBJECTIVE

This retrospective study critically analyzed the long-term functional outcomes and tumor recurrence rates for surgically treated craniopharyngiomas.

METHODS

This study used an outcome classification system that included functioning vision, independent versus dependent living, Karnofsky Performance Scale scores, academic levels, work status, and psychological status. Tumor recurrence rates were analyzed with respect to the extent of surgical resection and adjunctive radiotherapy.

RESULTS

For 121 patients, with a mean follow-up period of 10 years, the overall "good outcome" rate was 60.3%. Factors associated with poor outcomes included lethargy at presentation, visual deterioration, papilledema, tumor calcification, hydrocephalus, and tumor adhesiveness at surgery. Gross total resection was associated with good outcomes (P = 0.017) and decreased risk of recurrence (P = 0.024). Subtotal resection was associated with increased risk of tumor recurrence (P = 0.0235). The highest risk of recurrence was in the subtotal resection/no radiation group (P = 0.0001). There were no differences in outcomes or recurrence rates between pediatric and adult patients. There were also no differences in outcomes or recurrence rates between papillary and adamantinous tumors. Approximately one-third of patients exhibited morbid obesity, and permanent diabetes insipidus was observed for 25 patients.

CONCLUSION

A rigorous evaluation of outcomes for tumors such as craniopharyngiomas must consider not only the extent of resection, as judged by postoperative imaging, but also the long-term physical, intellectual, and psychological functioning of the patients.

Long-term results of biliary reconstruction after laparoscopic bile duct injuries

HYPOTHESIS

The Hepp-Couinaud approach to biliary enteric reconstruction for laparoscopic bile duct injuries provides a durable, long-term result in most patients.

DESIGN

Retrospective study of patients who underwent operative repair of laparoscopic bile duct injuries from January 1990 through December 1997.

SETTING

Academic tertiary referral center.

MAIN OUTCOME MEASURES

Outcome was assessed using a grading system based on clinical symptoms, liver function tests, and need for reintervention for anastomotic stricture. The Kaplan-Meier method was employed to estimate stricture-free survival.

RESULTS

Fifty-nine consecutive patients underwent operative repair of the following laparoscopic bile duct injuries (Strasberg classification): B: n = 2 (3%), C: n = 1 (1%), D: n= 2 (3%), E1: n= 5 (8%), E2: n= 16 (27%), E3: n= 25 (42%), E4: n = 5 (8%), and E5: n = 3 (5%). Forty-seven patients (80%) had 1 or more interventions prior to the index repair. The extrahepatic left bile duct (Hepp-Couinaud approach) was used in 46 of 53 patients who underwent a Roux-en-Y hepaticojejunostomy. Follow-up (mean+/-SEM, 3.7+/-0.3 years) was complete in 54 of the 57 patients still alive. Five patients developed subsequent anastomotic strictures and were treated with percutaneous transhepatic dilation (n = 3), endoscopic dilation (n = 1), and operative revision (n= 1). Excellent to good long-term results were achieved in the remaining 49 patients (91%). Life-table analysis yielded 95% and 88% chances of stricture-free survival at 2 and 5 years, respectively.

CONCLUSIONS

Complex iatrogenic proximal bile duct injuries and strictures are amenable to operative repair using the extrahepatic left bile duct. The Hepp-Couinaud approach offers a durable result in more than 90% of patients, even after previous interventions have failed.

Lone atrial fibrillation in elderly persons: a marker for cardiovascular risk

BACKGROUND

The risk of stroke in persons aged 60 years and younger with lone atrial fibrillation (LAF) is no greater than in the general population. The effect of older age on the risk of stroke in persons with LAF is less well established.

PARTICIPANTS AND METHODS

The risk of stroke in persons with LAF and without substantial comorbidities was examined in a population-based study at a single institution in Olmsted County, Minnesota, and compared with that in an age- and sex-matched population. The mean age was 74 years (range, 61-97 years). The median duration of follow-up was 9.6 years until death or last follow-up.

RESULTS

Of 55 patients, 26 had 31 cardiovascular events during follow-up, occurring a median of 5.1 years after diagnosis (range, 0.7-18 years). Of 11 cerebrovascular events, 6 were transient ischemic attacks and 5 were strokes. The event rates (percentage per person-year) were 0.9% for stroke, 1.1% for transient cerebral ischemia, and 2.6% for myocardial infarction, for a total cardiovascular event rate of 5.0% per person-year. The corresponding rates for the age- and sex-matched control group were 0.2%, 0%, and 1.1%, for a total of 1.3% per person-year. The incidence of total cardiovascular events was significantly greater (P< .01) in those with LAF, although there was no difference in survival.

CONCLUSION

Lone atrial fibrillation occurring after age 60 years is a risk marker for a substantial increase in cardiovascular events that warrants consideration for antithrombotic therapy.

Solitary pulmonary nodules: clinical prediction model versus physicians

OBJECTIVE

To determine whether a clinical prediction model developed to identify malignant lung nodules based on clinical data and radiologic lung nodule characteristics could predict a malignant lung nodule diagnosis with higher accuracy than physicians.

MATERIAL AND METHODS

One hundred cases were obtained by using a stratified random sample from a retrospective cohort of 629 patients with newly discovered 4- to 30-mm radiologically indeterminate solitary pulmonary nodules (SPNs) on chest radiography. A chest radiologist, pulmonologist, thoracic surgeon, and general internist made predictions of a malignant lesion and recommendations for management (thoracotomy, transthoracic needle aspiration biopsy, or observation) on the basis of radiologic and clinical data used to develop the clinical prediction rule. The predictions of a malignant lung nodule were compared with the probability of malignant involvement from a previously validated clinical prediction model to identify malignant nodules on the basis of three clinical characteristics (age, smoking status, and history of cancer greater than or equal to 5 years previously) and three radiologic characteristics (nodule diameter, spiculation, and upper lobe location).

RESULTS

Receiver operating characteristic analysis showed no significant difference between the logistic model and the physicians' predictions. Calibration curves revealed that physicians overestimated the probability of a malignant lesion in patients with low risk of malignant disease by the prediction rule; this finding suggests a potential for the decision rule to improve the management of patients with SPNs that are likely to be benign.

CONCLUSION

The prediction model was not better than physicians' predictions of malignant SPNs. The prediction rule may have potential to improve the management of patients with SPNs that are likely to be benign.

Functional outcome of excision of heterotopic ossification after total hip arthroplasty

Fifty-three cases of symptomatic heterotopic ossification were evaluated after total hip arthroplasty for the specific purpose of determining the value of surgical excision without revision or other concurrent procedures. The mean followup was 3.5 years for range of motion and 7.8 years for radiographic evaluation. A statistically significant increase in range of motion was obtained for the group at final followup. The mean increase in flexion arc was 34 degrees, abduction and adduction arc was 22 degrees, and rotation arc was 21 degrees. Of the patients who underwent surgical excision of heterotopic bone solely because of pain, none had complete alleviation of symptoms. It is concluded that surgical excision of heterotopic bone results in significant improvement in functional outcome, but it cannot be expected to predictably alleviate pain. Finally, the ultimate arc of motion was better than that suggested radiographically by the Brooker classification system.

The incidence and clinical consequences of treatment-related bowel injury

OBJECTIVE

To assess the frequency and clinical features of treatment-induced bowel injury in rectal carcinoma patients receiving perioperative external beam radiotherapy (EBRT). The frequency of and factors associated with treatment-induced intestinal injury have previously not been well quantified for rectal cancer patients. Postoperative adjuvant chemoirradiation is recommended for Stage II and III rectal cancers, making such data of significant interest.

METHODS AND MATERIALS

The records of 386 consecutive patients undergoing radiotherapy with or without chemotherapy (CT) for rectal carcinoma between 1981-90 were reviewed. Eight-two patients were excluded for receiving nontherapeutic EBRT or modalities other than EBRT.

RESULTS

Symptomatic acute treatment-related enteritis (within 30 days of EBRT +/- CT) was diagnosed in 13 patients, 3 of whom developed chronic bowel injury. Chronic treatment-related enteritis was identified in 18 patients and reoperation was required in 17 (5% of the 304 patients with complete follow-up). Chronic proctitis was documented in 38 patients, including 3 patients with small bowel injury. The probability of developing treatment-induced bowel injury at 5 years following treatment was 19%. Variables associated with an increased risk of bowel injury using multivariate analysis were transanal excision (p = 0.002), escalating radiation dose (p = 0.005), and increasing age (p = 0.01). Twenty of the affected patients required operative treatment, and 2 deaths resulted from treatment-induced enteritis.

CONCLUSION

Patients with rectal carcinoma treated with EBRT +/- CT have the risk of developing treatment-induced bowel injury. The pelvic radiation dose should be limited to < or = 5040 cGy unless small bowel can be displaced. Reperitonealization of the pelvis, or other surgical methods of excluding the small intestine should be used whenever possible.

Mid-term results of endoscopic perforator vein interruption for chronic venous insufficiency: lessons learned from the North American subfascial endoscopic perforator surgery registry. The North American Study Group

PURPOSE

The safety, feasibility, and early efficacy of subfascial endoscopic perforator surgery (SEPS) for the treatment of chronic venous insufficiency were established in a preliminary report. The long-term clinical outcome and the late complications after SEPS are as yet undetermined.

METHODS

The North American Subfascial Endoscopic Perforator Surgery registry collected information on 148 SEPS procedures that were performed in 17 centers in the United States and Canada between August 1, 1993, and February 15, 1996. The data analysis in this study focused on mid-term outcome in 146 patients.

RESULTS

One hundred forty-six patients (79 men and 67 women; mean age, 56 years; range, 27 to 87 years) underwent SEPS. One hundred and one patients (69%) had active ulcers (class 6), and 21 (14%) had healed ulcers (class 5). One hundred and three patients (71%) underwent concomitant venous procedures (stripping, 70; high ligation, 17; varicosity avulsion alone, 16). There were no deaths or pulmonary embolisms. One deep venous thrombosis occurred at 2 months. The follow-up periods averaged 24 months (range, 1 to 53 months). Cumulative ulcer healing at 1 year was 88% (median time to healing, 54 days). Concomitant ablation of superficial reflux and lack of deep venous obstruction predicted ulcer healing (P <.05). Clinical score improved from 8.93 to 3.98 at the last follow-up (P <. 0001). Cumulative ulcer recurrence at 1 year was 16% and at 2 years was 28% (standard error, < 10%). Post-thrombotic limbs had a higher 2-year cumulative recurrence rate (46%) than did those limbs with primary valvular incompetence (20%; P <.05). Twenty-eight of the 122 patients (23%) who had class 5 or class 6 ulcers before surgery had an active ulcer at the last follow-up examination.

CONCLUSIONS

The interruption of perforators with ablation of superficial reflux is effective in decreasing the symptoms of chronic venous insufficiency and rapidly healing ulcers. Recurrence or new ulcer development, however, is still significant, particularly in post-thrombotic limbs. The reevaluation of the indications for SEPS is warranted because operations in patients without previous deep vein thrombosis are successful but operations in those patients with deep vein thrombosis are less successful. Operations on patients with deep vein occlusion have poor outcomes.

Venting intraluminal drains in pancreaticoduodenectomy

The utility of placing biliary, pancreatic, or enteric "venting"tubes (externally draining devices traversing the bowel or bile duct that have their distal tip located intraluminally near the biliary or pancreatic anastomosis) when performing a pancreaticoduodenectomy has received little attention to date. We hypothesize that these venting tubes do not decrease the morbidity or mortality associated with pancreaticoduodenectomy and may actually be a source of additional morbidity. To characterize our use of and the effect of these drains, we retrospectively analyzed 136 pancreaticoduodenectomies (127 partial, 9 total) performed over a 24-month period. Venting drain use, drain type and size, drain location, duration of intubation, hospital course, and postoperative complications were noted. Venting tubes were used in 80 patients (59%). The use of these drains had no significant relationship to postoperative length of stay, the development of major complications, overall morbidity, or mortality (P>0.05). Such drains also did not significantly shorten the length of hospital stay (P>0.05) or improve outcome when available to augment local control following luminal leak (n = 6) or regional abscess (n = 7). These drains were removed at a median interval of 29 days postoperatively (range 6 to 77 days). Seven patients had complications that were directly related to the venting drain; four of these patients had a documented intra-abdominal luminal leak from the site of drain removal, whereas the other three were hospitalized for presumed leakage secondary to immediate, severe abdominal pain following removal of the drain. These seven patients were elderly (mean age 70 years) and often harbored pancreatic ductal carcinoma (n = 6). Intraluminal drains afford no distinct advantage in terms of shortening the postoperative length of stay, decreasing operative morbidity and mortality, or improving local control with regional sepsis in pancreaticoduodenectomies. Furthermore, they may add an additional source of morbidity and we no longer employ them routinely.

Human herpesvirus 6 seronegativity before transplantation predicts the occurrence of fungal infection in liver transplant recipients

BACKGROUND

Invasive fungal infection has a major impact on the morbidity and mortality of liver transplant recipients. Human herpesvirus (HHV)-6 infection after transplantation is associated with an immunosuppressive state and the development of cytomegalovirus disease. Because cytomegalovirus infection is a risk factor for invasive fungal infection after transplantation, we have examined whether HHV-6 and fungal infection are associated after transplantation.

METHODS

Pretransplantation sera from 247 consecutive liver transplant recipients were analyzed for IgG to HHV-6. Thirty-three (13%) HHV-6-seronegative recipients were identified. Six of 33 (18%) seronegative recipients experienced fungal infection as compared with 15 of 214 (7%) seropositive recipients (P=0.034).

RESULTS

In a univariate analysis of risk factors for fungal infection, pretransplantation seronegativity to HHV-6 (P=0.034), intraoperative cryoprecipitate requirements greater than the 75th percentile (P=0.035), reoperation (P=0.005), biliary stricturing postoperatively (P=0.046), and gastrointestinal or vascular complications postoperatively (P=0.030) were identified as significant risk factors. Moreover, in pairwise multivariate analysis, pretransplantation HHV-6 seronegativity remained a significant variable even in the presence of each of the other variables.

CONCLUSIONS

These results suggest that HHV-6 seronegativity before transplantation is a valuable clinical marker that identifies patients at risk for developing fungal infection after transplantation.

Improved prognosis of thoracic aortic aneurysms: a population-based study

CONTEXT

Managing thoracic aortic aneurysms identified incidentally by increased use of computed tomography, echocardiography, and magnetic resonance imaging is problematic, especially in the elderly.

OBJECTIVE

To ascertain whether the previously reported poor prognosis for individuals with thoracic aortic aneurysms has changed with better medical therapies and improved surgical techniques that can now be applied to aneurysm management.

DESIGN

Population-based cohort study.

SETTING AND PATIENTS

All 133 patients with the diagnosis of degenerative thoracic aortic aneurysms among Olmsted County, Minnesota, residents between 1980 and 1994 compared with a previously reported cohort of similar patients between 1951 and 1980.

MAIN OUTCOME MEASURES

The primary clinical end points were incidence, cumulative rupture risk, rupture risk as a function of aneurysm size, and survival.

RESULTS

In contrast to abdominal aortic aneurysms, for which men are affected predominately, 51% of thoracic aortic aneurysms were identified in women who were considerably older at recognition than men (mean age, 75.9 vs 62.8 years, respectively; P= .01). The overall incidence rate of 10.4 per 100000 person-years (95% confidence interval [CI], 8.6-12.2) between 1980 and 1994 was more than 3-fold higher than the rate from 1951 to 1980. The cumulative risk of rupture was 20% after 5 years. Seventy-nine percent of ruptures occurred in women (P= .01). The 5-year risk of rupture as a function of aneurysm size at recognition was 0% for aneurysms less than 4 cm in diameter, 16% (95% CI, 4%-28%) for those 4 to 5.9 cm, and 31% (95% CI, 5%-56%) for aneurysms 6 cm or more. Overall 5-year survival improved to 56% (95% CI, 48%-66%) between 1980 and 1994 compared with only 19% between 1951 and 1980 (P<.01).

CONCLUSIONS

In this population, elderly women represent an increasing portion of all patients with clinically recognized thoracic aortic aneurysms and constitute the majority of patients whose aneurysm eventually ruptures. Overall survival for thoracic aortic aneurysms has improved significantly in the past 15 years.

Primary chondrosarcoma of long bones and limb girdles

BACKGROUND

Chondrosarcomas are common solid malignant tumors of bone, second in incidence only to osteosarcomas. The biologic evolution of chondrosarcomas is slow, requiring long follow-up intervals for meaningful survival analysis.

METHODS

This study describes the clinicopathologic profiles of 344 patients, 194 male and 150 female (M:F, 1.3:1.0), with primary chondrosarcoma of long bones and limb girdles seen at 1 institution over a period of 80 years.

RESULTS

The average age at presentation was 46 years (range, 5-82 years). The pelvis was the most common location (1.7% of all patients). Local pain was the most frequently reported initial symptom (81.4%). Survival analysis was limited to 233 patients whose primary treatment was given at the Mayo Clinic. All 233 patients had potential follow-up of at least 5 years. The overall 5-year survival rate was 77% (the expected rate was 96%). Local recurrence developed in 19.7% of patients and metastatic lesions in 13.7%. The recurrence rate was higher for tumors of the shoulder and pelvis than for tumors of long bones. Radiographically, chondrosarcomas had a characteristic appearance, including a combination of bone expansion and cortical thickening. Entering the tumor at surgery increased the risk of local recurrence. Histologic tumor grade was an important predictor of local recurrence and metastasis.

CONCLUSIONS

With adequate initial surgical intervention, chondrosarcoma is primarily a local disease with a low metastatic rate.

Risk factors for prosthetic joint infection: case-control study

We conducted a matched case-control study to determine risk factors for the development of prosthetic joint infection. Cases were patients with prosthetic hip or knee joint infection. Controls were patients who underwent total hip or knee arthroplasty and did not develop prosthetic joint infection. A multiple logistic regression model indicated that risk factors for prosthetic joint infection were the development of a surgical site infection not involving the prosthesis (odds ratio [OR], 35.9; 95% confidence interval [CI], 8.3-154.6), a National Nosocomial Infections Surveillance (NNIS) System surgical patient risk index score of 1 (OR, 1.7; 95% CI, 1.2-2.3) or 2 (OR, 3.9; 95% CI, 2.0-7.5), the presence of a malignancy (OR, 3.1; 95% CI, 1.3-7.2), and a history of joint arthroplasty (OR, 2.0; 95% CI, 1.4-3.0). Our findings suggest that a surgical site infection not involving the joint prosthesis, an NNIS System surgical patient risk index score of 1 or 2, the presence of a malignancy, and a history of a joint arthroplasty are associated with an increased risk of prosthetic joint infection.

Cytomegalovirus and its association with hepatic artery thrombosis after liver transplantation

BACKGROUND

Hepatic artery thrombosis (HAT) is a cause of morbidity and graft loss in approximately 7% of patients after an orthotopic liver transplantation (OLT). Although technical problems are often thought to be the cause of HAT, in general the etiology remains unclear. Because cytomegalovirus (CMV) can infect endothelial cells in vitro and lead to a rapid procoagulant response, it can be hypothesized that, in the absence of CMV antibodies, latent CMV in an allograft may become activated and promote or contribute to vascular thrombosis. Therefore, the purpose of this study was to examine the relationship between CMV serology of the donor and recipient with the development of HAT after OLT.

METHODS

Between July 1988 and November 1995 (University of Wisconsin era), 490 OLTs were performed in 413 patients. Subsequently, four patients were excluded in whom the CMV serology results of the donor were not available. Sixteen of the 409 patients developed HAT within 30 days after liver transplantation. The control group consisted of the other 393 patients.

RESULTS

The incidence of HAT was 12.5% in 64 CMV D+R- patients and 0% in 52 CMV D-R- patients. However, in the other combinations (D+R+ and D-R+), the incidence was only 2.8% (P = 0.005). Eight of the 16 patients with HAT belonged to the CMV D+R- group.

CONCLUSIONS

We conclude that CMV-seronegative patients receiving a seropositive allograft may be at risk for early HAT. Seropositivity of the donor alone and of the recipient alone was not significantly related to the incidence of HAT. Prophylactic treatment with ganciclovir and/or anticoagulation should be evaluated to prevent this complication.

Transabdominal preperitoneal laparoscopic inguinal herniorrhaphy: assessment of initial experience

OBJECTIVE

To evaluate our initial experience with laparoscopic inguinal herniorrhaphy.

DESIGN

We retrospectively studied a consecutive series of patients selectively chosen for laparoscopic repair of inguinal hernia.

MATERIAL AND METHODS

The study cohort consisted of 173 patients treated by a single surgeon between 1992 and 1995. For all operations, a transabdominal approach was used. Follow-up was obtained by telephone contact or letter.

RESULTS

The study group consisted of 167 male and 6 female patients with a mean age at operation of 55 years (range, 15 to 81). During the study period, 206 laparoscopic inguinal hernia repairs were performed in the 173 patients. Only one patient (0.6%) required conversion to laparotomy. Bilateral hernia repair was done in 31 patients (18%). Of the 206 procedures, 63 repairs (31%) were performed for recurrent hernias. In 69% of the patients, the procedure was completed on an outpatient basis. Early postoperative complications necessitating surgical intervention occurred in four patients. The median time to return to work or normal physical activity was 7 days for unilateral and 12 days for bilateral hernia repair (P = 0.18). A mean follow-up of 29 months was obtained for 171 patients (99%). In six patients (3%), a recurrent hernia developed. Four of these six patients had previously undergone an open surgical procedure on the side of the recurrence.

CONCLUSION

Laparoscopic inguinal herniorrhaphy is a feasible alternative to open hernia repair. This operation, however, should be reserved for selected patients. Longer follow-up and controlled trials comparing laparoscopic and tension-free open herniorrhaphy are necessary for assessment of the relative benefits of this procedure.

Surgical management of intrahepatic cholangiocarcinoma: a 31-year experience

Intrahepatic cholangiocarcinoma (ICC) is the second most common malignant primary tumor of the liver. It is, though, a rare tumor and little is known regarding its natural history, clinicopathologic characteristics, or the outcomes of surgical therapy. We reviewed the experience of 61 patients with ICC seen by the surgical service at the Mayo Clinic over a 31-year period. Patient demographic and clinical data were recorded, as were survival statistics. Pathologic data were also obtained and patients stratified according to the TNM classification. Twenty-eight patients were resected for cure. Overall, 45 patients died of ICC. Of the patients resected for cure, survival at 3 years was 60%. No pathologic condition was found to be associated with the development of ICC. Overall survival correlated with stage of the tumor. Among patients resected for cure, stage did not correlate with survival. Prognosis for patients with ICC remains poor; resection, though, appears to prolong survival.

Advanced multiple beam equalization radiography: receiver operating characteristic comparison with screen-film chest radiography

OBJECTIVE

To test the hypothesis that the advanced multiple beam equalization radiography (AMBER) imaging system is superior to conventional chest radiography in the demonstration of diffuse infiltrative lung disease, emphysema, pulmonary nodules, calcification within nodules, and mediastinal or hilar masses and lymphadenopathy.

MATERIAL AND METHODS

The study involved 115 patients, each of whom underwent chest computed tomography (CT), AMBER, posteroanterior chest radiography, and conventional posteroanterior stereoscopic chest radiography (two films). All radiographs were obtained with the InSight Thoracic Imaging System. Four chest radiologists independently analyzed the 115 AMBER studies, 115 unpaired single conventional radiographs (a single film from a stereoscopic pair), and 115 stereoscopic conventional radiographs (2 films) for the presence of diffuse infiltrative lung disease, emphysema, pulmonary nodules, calcification within nodules, and mediastinal or hilar masses and lymphadenopathy. For each abnormality detected, the radiologists described their level of confidence based on a scale of 1 to 5. The 115 CT examinations were interpreted by consensus among 3 of the chest radiologists. The CT results were considered the standard. Receiver operating characteristic (ROC) techniques were used for statistical analysis.

RESULTS

No statistically significant differences were found with ROC techniques between the AMBER system and single or stereoscopic conventional screen-film radiography for the abnormalities studied.

CONCLUSION

We noted no clinically significant difference between AMBER and either single or stereoscopic conventional screen-film radiography in this prospective study of 115 patients in which CT (performed within 1 week of both radiographic examinations) was the standard.

Prognostic factors: guidelines for investigation design and state of the art analytical methods

The proliferation of putative prognostic factors, derived prognostic indices and computerised prediction of outcome in surgical oncology has led to some confusion over the exact methods available for deriving clinically significant prognostic factors. The realisation that the interaction between factors is often complex and non-linear has led to the development of new statistical techniques. The aim of this article is to review the currently available methods of analysis. A review of the relevant literature available from statistical, medical and computer science sources was performed. Information has been conveyed at a level aimed at producing a practical understanding of the techniques involved rather than their underlying mathematical basis. There are now clear guidelines for the investigation of putative prognostic factors (Table 1). The established role of linear statistical models and prognostic indices remains vitally important for the majority of diseases with many derived prognostic indices having been validated in a prospective fashion. However, in order to improve the delineation of prognostic factors other more complex methods of analysis are now being utilised. Furthermore, the recognition of complex dynamic non-linearity within biological systems has led to the increasing use of non-linear statistical techniques and artificial intelligence. As such it is incumbent upon the modern clinician to be able to understand the basic assumptions required for multivariate analysis and also to realise when alternative statistical techniques should be employed.

Can adrenal incidentalomas be safely observed?

We currently recommend excision of adrenal incidentalomas > or = 4 cm in size and all hormonally active tumors. The optimal management and follow-up of smaller nonfunctioning tumors are controversial. The aim of this study was to determine the clinical outcome of a well defined population of patients with incidentalomas followed without operative intervention. The study group comprised 231 patients, identified from the records of abdominal or thoracic computed tomographic (CT) scans performed between 1985 and 1989. The primary outcome variable analyzed was survival. Follow-up was obtained by office records, telephone contact, or letter. There were 101 male and 130 female patients with a mean age at diagnosis of 64 years (range 5-86 years). Most adrenal tumors were unilateral (right 113; left 98); 20 were bilateral. Mean tumor size was 2 cm (range 1-6 cm). In nine (4%) patients the tumor was > or = 4 cm. Follow-up [mean 7 years; range 1 month (patient died) to 11.7 years] was complete in 224 (97%) patients. Ninety-one (39%) patients had one or more additional CT scans performed during the follow-up period, with only four patients demonstrating a > 1 cm increase in the size of the adrenal mass. Surgical excision of these four lesions identified benign pathology. Eighty-one (35%) patients died of conditions unrelated to adrenal pathology. No patient developed subsequent adrenal hyperfunction or adrenal malignancy. Within the context of our guidelines, conservative management of adrenal incidentalomas considered benign or nonfunctioning at diagnosis is appropriate. Additional information provided by repeat CT scanning appears to confer limited benefit. This study does not support laparoscopic removal of small, nonfunctional adrenal tumors, as has been suggested.

Laparoscopic versus open posterior adrenalectomy: comparison of acute-phase response and wound healing in the cushingoid porcine model

This prospective randomized study examined the acute-phase response and wound healing, comparing laparoscopic (LA) and open posterior (PA) adrenalectomy in a cushingoid porcine model. Repository corticotropin gel was given to 40 pigs for 21 days. Biochemical and tissue parameters of Cushing syndrome were confirmed. The pigs were randomized to undergo LA or PA. In addition to operating time and morbidity, the acute-phase response was compared by measuring the postoperative white blood cell count, fasting glucose, C-reactive protein, and nitrogen balance. Wound healing was assessed by (1) scored (1-4) gross appearance at 48 hours and 1 and 2 weeks; (2) histologic examination; and (3) tensile strength. There was no difference in operating time (mean +/- SD) (36 +/- 9 minutes open vs. 37 +/- 7 minutes laparoscopic), perioperative mortality, degree of leukocytosis, fasting glucose, or C-reactive protein (p > 0.05). Nitrogen balance, wound scores, and tensile strength at 24 hours and 1 week were more favorable in the LA group than in the PA group (p < 0.05). In the cushingoid porcine model, laparoscopic adrenalectomy was less catabolic and was associated with fewer wound complications than the open posterior adrenalectomy. These findings provide support for continued pursuit of laparoscopic methods for adrenalectomy in the clinical setting.

Molecular, serological, and clinical features of 16 consecutive cases of invasive streptococcal disease. Southeastern Minnesota Streptococcal Working Group

We performed a comprehensive analysis of the molecular, serological, and clinical features of 16 consecutive cases of invasive streptococcal disease (ISD). The majority of cases were linked to two group A streptococcus (GAS) clones closely related by pulsed-field gel electrophoresis (PFGE) and designated as PFGE-1 and PFGE-1.1. These clones, serotyped as M-3, T-3/B3264, carried an allelic variant of the gene that encodes pyrogenic exotoxin A (speA3) and the gene that encodes streptococcal superantigen (SSA) but different emm alleles that encode M-protein. The characteristics and clinical features of patients were similar to those described in previous reports, regardless of the responsible GAS clone. However, worse clinical outcomes (shock and death) were more frequent when patients infected with PFGE1/1.1 clones were considered as a group and compared with all other patients as a group. One striking feature in some patients with deep tissue infection was a lack of inflammatory cells despite the presence of numerous streptococci. An evaluation of PFGE profiles of GAS isolated elsewhere demonstrated that the PFGE-1 clone has caused invasive disease in other locations in the United States and in Japan.

Development of an adjustable prosthesis for the treatment of gastroesophageal reflux: preliminary results in a porcine model

Dysphagia and recurrent gastroesophageal reflux complicate use of the Angelchik prosthesis. The authors developed an inflatable silicone device, similar to the Angelchik prosthesis, that may allow for the adjustment of the total pressure exerted around the gastroesophageal junction after implantation. To estimate its potential to prevent gastroesophageal reflux in humans, we used a short-term porcine model in which we measured the effective lower esophageal sphincter pressure in 10 anesthetized pigs using a computerized, three dimensional pressure vector volume analysis. Anesthesia and mobilization of the gastroesophageal junction did not modify the three dimensional pressure vector volume at the lower esophageal sphincter. Implantation of the deflated device significantly increased effective lower esophageal sphincter three dimensional pressure vector volume compared with baseline. Inflation of the device with 30 ml of saline further increased lower esophageal sphincter pressure significantly. Deflation of the device returned the pressure to the pre-inflation values. Using an animal model and short-term implantation, this new antireflux device appeared to offer the potential ability to adjust the pressure selectively at the gastroesophageal junction postoperatively. An added future feature of this device may be the ease of insertion using laparoscopic techniques. Long-term animal implantation studies and clinical trials are required to help establish the safety and efficacy of this device in humans.

The natural history of debonding of the femoral component from the cement and its effect on long-term survival of Charnley total hip replacements

Two hundred and ninety-seven consecutive Charnley total hip replacements that had been followed for at least twenty years or until revision or death were analyzed to determine the effect of early debonding of the smooth-surfaced femoral component on its subsequent survival. Radiographically evident debonding was not found to have a significant effect, with the numbers available, on the long-term survival of the femoral component when the maximum thickness of the radiolucent line between the superolateral border of the prosthesis and the cement had been less than 2.0 millimeters during the first one to five years after the operation. The radiographic finding of debonding also was not found to be associated with pain in the hip. These data show that most components with early debonding functioned well during a long period of follow-up and suggest that debonding of a smooth femoral component of a Charnley total hip replacement should not be considered to be analogous to loosening. In contrast, when the maximum thickness of the radiolucent line between the superolateral border of the prosthesis and the cement was 2.0 millimeters or more, an early appearance of debonding was associated with a significantly poorer (p < 0.0001) probability of survival of the Charnley femoral component without revision because of aseptic loosening. Thus, pronounced early subsidence of the component within the cement mantle had a strong negative impact on the long-term performance of the implant. The results of the present study should not be extrapolated to prostheses with substantially different design characteristics, as it appears that different types of femoral components behave differently when debonding occurs.

Comparison of North American Symptomatic Carotid Endarterectomy Trial and population-based outcomes for carotid endarterectomy

PURPOSE

The North American Symptomatic Carotid Endarterectomy Trial (NASCET) advocated the use of carotid endarterectomy (CEA) for transient ischemic attacks (TIAs), nondisabling strokes, and ipsilateral high-grade stenosis in highly selected patients. Whether similar results are achieved when CEA is applied to an entire geographically defined population is unknown but important if the NASCET recommendations are to be applied broadly to all community patients.

METHODS

To determine the survival rate to ipsilateral stroke after CEA for all symptomatic patients in a defined population, we reviewed the medical records of all patients residing in Olmsted County, Minn. (approximately 100,000), who underwent a CEA for TIA or nondisabling stroke between 1970 and 1995. Their outcomes were compared with the NASCET results.

RESULTS

In the community of Olmsted County, 297 patients (108 women and 189 men) underwent 322 CEAs during the study period. TIAs or nondisabling stroke was the indication in 254 patients (86%), whereas the remaining 14% had asymptomatic stenosis. After CEA for symptomatic lesions, survival rate free of ipsilateral stroke was 97% at 2 years, 93% at 5 years, and 92% at 10 years. These results are similar to the NASCET survival rates free of ipsilateral stroke at 2 years (91%). However, the 30-day postoperative stroke rate for patients older than 80 years was significantly higher than that for patients younger than 80 years.

CONCLUSIONS

When the NASCET results are compared with a population-based experience in which all symptomatic patients undergoing CEA were analyzed, the early outcomes were similar. Our population-based data also document the remarkably durable long-term results of CEA in preventing stroke and present another benchmark for carotid stent angioplasty.

Prophylactic oophorectomy in colorectal carcinoma: preliminary results of a randomized, prospective trial

Controversy exists regarding the role of prophylactic oophorectomy during resection for primary colorectal cancer.

PURPOSE

A prospective, randomized trial was initiated to evaluate the influence of oophorectomy on recurrence and survival in patients with Dukes Stages B and C colorectal cancer.

METHOD

Between November 1986 and March 1997, 155 patients were randomized to oophorectomy or no oophorectomy at laparotomy for resection of colorectal cancer.

RESULTS

No incidence of gross or microscopic metastatic disease to the ovary was found among 77 patients randomized to oophorectomy, in contrast to previous reports. Preliminary crude survival curves suggested a survival benefit for oophorectomy between two and three years from surgery, but Kaplan-Meier survival analysis indicated that this was not statistically significant and the benefit does not appear to persist at five years. Kaplan-Meier curves of recurrence-free survival, however, suggest a more substantial separation of the curves, with 80 percent vs. 65 percent five-year disease-free survival for oophorectomy vs. nonoophorectomy, but further patient accrual is necessary to provide sufficient statistical power.

CONCLUSIONS

Occult colorectal carcinoma metastatic to the ovaries has not been documented in this series of putative Dukes Stages B and C tumors. The possibility of a recurrence-free survival advantage emphasizes the need to continue this preliminary work.

Survival after surgical treatment for primary hyperparathyroidism

BACKGROUND

Reports have suggested that patients with primary hyperparathyroidism (pHPT) are at increased risk for premature death, even when they reach normocalcemia. This study addresses factors that may be of relevance for long-term outcome.

METHODS

Between 1980 and 1984, 1052 patients (27% men and 73% women; median age, 59 years) underwent initial cervical exploration for pHPT. Long-term follow-up was obtained with regard to overall survival and cause of death. By using univariate and multivariate (Cox) survival analysis, subgroups of patients were compared.

RESULTS

Median follow-up was 12 years (range, 0 to 15 years). Overall, survival was not decreased compared with the expected survival of a gender- and age-matched midwest population. Survival was better in patients with a history of kidney stones (p = 0.044), without osteoporosis (p = 0.004), and without muscle weakness (p = 0.013).

CONCLUSIONS

Decreased long-term survival was not evident in this study. Age at the time of initial surgical treatment and the degree of endocrine activity of the diseased glands appear to be the most important independent prognostic factors for survival. Comparison of these data to prior Scandinavian data is not justified, principally because of the less advanced stage of disease in this study.

Laparoscopic versus open posterior adrenalectomy: a case-control study of 100 patients

BACKGROUND

Few controlled studies have compared laparoscopic transabdominal adrenalectomy (LA) to conventional open posterior adrenalectomy (PA).

METHODS

Five patients have undergone successful LA at our institution between 1992 and 1996. A matched case-control study of 50 PA patients was performed during a similar time period.

RESULTS

Follow-up was complete in 82% of patients with a mean follow-up time of 25 months. There were no statistically significant differences between the LA and PA groups with regard to the following demographic features: age, gender, endocrine disorder, side and size of tumor, and body habitus. Statistically significant differences (p < 0.05), however, were present (LA vs PA) when we compared the following results: mean hospital stay (3.1 versus 5.7 days), narcotic equivalents (28 versus 48), return to normal activity (3.8 versus 7 weeks), patient satisfaction (9 versus 7 [scale 1 to 10, 10 being most satisfied]), late morbidity (0 versus 54%), and operating room time (167 versus 127 minutes). Median hospital charges ($7,000 versus $6,000) were slightly higher in the LA group (p = 0.05).

CONCLUSIONS

Although LA is technically more demanding and slightly more expensive to perform, advances appear to exist for LA with regard to patient comfort, patient satisfaction, hospital stay, and return to normal daily activities. Late incisional complications are dramatically less in the LA group.

Seroconversion to human herpesvirus 6 following liver transplantation is a marker of cytomegalovirus disease

Human herpesvirus 6 (HHV-6) infection is common after transplantation; HHV-6 is known to interact with other viruses and induce immunosuppression. Whether HHV-6 plays a role in the occurrence of cytomegalovirus (CMV) infection after transplantation was investigated. In a cohort of 247 liver transplant recipients, HHV-6 seroconversion was identified as a significant risk factor for development of symptomatic CMV infection (P < .001), including CMV organ involvement (P < .001), even in the presence of the other significant risk factors: D+/R- CMV serologic status (P < .001) or use of OKT3 after transplantation (P = .002). Subgroup analysis indicated that HHV-6 seroconversion was significantly associated with symptomatic CMV infection in the D+/R+ but not in the D+/R- CMV serologic group (P < .001 and P = .11, respectively). These results indicate that HHV-6 seroconversion is a marker for CMV disease after transplantation and suggest that additional studies using more sensitive diagnostic techniques are warranted to determine the relationship between HHV-6 and CMV infection after transplantation.

Cataract extraction rates in Olmsted County, Minnesota, 1980 through 1994

OBJECTIVE

To analyze population-based trends in cataract extraction.

DESIGN

Rochester Epidemiology Project databases; which capture virtually all health care services provided to residents of Olmsted County, Minnesota, were used to perform retrospective cohort analyses of rates of primary cataract extractions performed between 1980 and 1994.

PARTICIPANTS

The population of Olmsted County, Minnesota.

MAIN OUTCOME MEASURES

Incidence rates adjusted to the age and sex distribution of the 1990 US white population were analyzed using Poisson regression.

RESULTS

The 4257 procedures performed on 3176 patients of all ages represented overall annual age-adjusted rates of 404 procedures per 100,000 females and 320 per 100,000 males. Annual age- and sex-adjusted rates for both sexes combined rose from 133 procedures per 100,000 in 1980 to a peak of 507 per 100,000 in 1992. The rates fell to 470 per 100,000 in 1994. Manual review of a random sample of records estimated case overascertainment at 0.9%.

CONCLUSIONS

With the exception of 1988 and 1989, rates of cataract surgery in this geographically circumscribed population increased every year between 1980 and 1992. Data from 1993-1994 indicate that rates may have plateaued and possibly declined slightly. If sustained, these patterns could have major implications for future utilization of ophthalmologic resources.

Paget's disease of the perianal region--an aggressive disease?

BACKGROUND

Perianal Paget's disease is a rare entity, often associated with internal malignancies and a poor prognosis.

METHODS

A chart review of patients with perianal Paget's disease who presented consecutively to Mayo during 25 years (starting in January 1970) was made. Patients included had Paget's disease located in or around the anus (3 cm). Patients were excluded for evidence of spread of vulvaperineal lesions or pagetoid extension of a rectal adenocarcinoma. Histology slides were reviewed, and immunohistochemistry was applied to confirm diagnoses. Follow-up was updated in all patients. Recurrence and survival curves were generated by the Kaplan-Meier method. Survival was compared with an age-matched population by the log-rank test.

RESULTS

Thirteen patients, eight females, were diagnosed (age +/- standard deviation of 68.3 +/- 10.6 years). All histologic diagnoses were confirmed with immunohistochemical staining results. Mean follow-up was 6.7 years, 8.8 for living patients. One patient had associated extramammary Paget's disease (scrotum). Lesions were located randomly at the dentate line, anal verge, and/or perianal area. Four patients had associated carcinomas; none of them were visceral. Eleven patients underwent local resection, without adjuvant therapy. Almost all recurrences were treated by wider local excision. The five-year recurrence rate was 61 percent. Overall five-year and ten-year survival was 67 percent, no different from the age-matched population (P = 0.546).

CONCLUSIONS

These results do not reflect an aggressive nature of perianal Paget's disease, despite a high rate of local recurrence. Both primary lesions and recurrences are susceptible to treatment by wider local resection. Long-term survival is no different from that of the normal age-matched population.

Detection of colorectal polyps with CT colography: initial assessment of sensitivity and specificity

PURPOSE

To estimate the sensitivity and specificity of computed tomographic (CT) colography in detection of colorectal polyps and to compare these findings with those at axial CT.

MATERIALS AND METHODS

In 70 consecutive patients, CT colography and colonoscopy were performed. Helical axial CT images and CT colographic images (multiplanar two- and three-dimensional endoluminal images) were evaluated separately by two radiologists blinded to results from colonoscopy and other imaging studies. Findings were compared with those at colonoscopy, which was the standard.

RESULTS

The sensitivity and specificity for the two observers with CT colography averaged 75% and 90% in patients with adenomas 10 mm in diameter or larger, 66% and 63% in patients with adenomas 5 mm in diameter or greater, and 45% and 80% for patients with adenomas less than 5 mm in diameter, respectively. Sensitivity and specificity with axial CT were lower than those with CT colography (58% and 74%, respectively) in patients with adenomas 10 mm in diameter or larger.

CONCLUSION

Compared with axial CT, CT colography appears to have superior sensitivity and specificity in detection of clinically important colorectal adenomas. Early performance of CT colography seems promising for detection of colorectal polyps 5 mm and larger.

Effect of the elevated-rim acetabular liner on loosening after total hip arthroplasty

Elevated-rim acetabular liners recently were shown to be associated with improved stability of total hip prostheses in a large clinical series. However, the effect of this design on loosening remains unknown. To address this question, we reviewed the results of 5167 primary and revision total hip arthroplasties that had been performed at our institution from September 1, 1985, through December 31, 1991; 2469 of the acetabular components had an elevated-rim liner (10 degrees of elevation), and 2698 had a standard liner. Five-year follow-up data were available for 1237 hips (174 that had an elevated-rim acetabular liner and 1063 that had a standard acetabular liner). The cumulative probability of revision because of loosening of the implant was estimated as a function of time since the operation with use of the Kaplan-Meier survivorship method. The five-year probability of survival of the acetabular component was 98.8 per cent (95 per cent confidence interval, 97.9 to 99.6 per cent) for the prostheses that had an elevated-rim liner and 98.3 per cent (95 per cent confidence interval, 97.7 to 99.0 per cent) for those that had a standard liner (p = 0.87). The effect of the elevated-rim acetabular liner on the probability of revision because of loosening of the acetabular or the femoral component was analyzed for several subgroups: components inserted with cement, components inserted without cement, primary total hip arthroplasties, revision total hip arthroplasties, male patients, and female patients. With the numbers available, no significant differences were found in the probability of survival of the acetabular or the femoral component in any of the subgroups. Theoretical considerations suggest that the geometric design of the elevated-rim acetabular liner may have biomechanical characteristics that predispose the implant to early loosening. However, our initial review of the results of total hip arthroplasties after a mean follow-up period of five years (range, 0.25 to ten years) failed to demonstrate any difference in the cumulative probability of revision because of loosening of the implant. Continued surveillance is warranted and ongoing.

Complications after concomitant bilateral total knee arthroplasty in elderly patients

OBJECTIVE

To determine the risks associated with performance of bilateral total knee arthroplasty (TKA) in elderly patients.

MATERIAL AND METHODS

Ninety-eight patients with osteoarthritis who were 80 years of age or older and underwent concomitant cemented bilateral TKA were matched (on the basis of gender, surgeon, year of surgical treatment, age, and diagnosis) with 98 patients who underwent cemented unilateral TKA to compare the number and types of complications in these two groups. The groups did not differ in the number and type or severity of premorbid medical conditions, anesthetic risk, and type of anesthesia.

RESULTS

One hundred nineteen postoperative complications occurred in 63 patients in the bilateral TKA group; in contrast, 72 complications occurred in 49 patients in the unilateral TKA group. The difference between the two groups in the total number of complications was significant. Specifically, significant differences between the two groups were noted in the occurrence of cardiovascular and neurologic complications. On paired analysis, congestive heart failure and acute delirium were found to be significantly more frequent in the bilateral TKA group than in the unilateral TKA group. We noted a trend toward an increased mortality rate in the bilateral group (four patients) versus the unilateral group (no deaths).

CONCLUSION

Patients 80 years of age or older who undergo concomitant bilateral TKA are at increased risk for cardiovascular and neurologic complications during the postoperative period in comparison with matched patients who undergo unilateral TKA.

Management of colonoscopic perforations

OBJECTIVE

To document our evolving surgical management of colonoscopic perforation and examine factors crucial to the improvement of patient care.

DESIGN

We conducted a computer-based retrospective analysis of medical records (1980 through 1995).

MATERIAL AND METHODS

Among 57,028 colonoscopic procedures performed, 43 patients (0.075%, or 1 perforation in 1,333 procedures) had a colonic perforation. Two additional patients were treated after colonoscopy performed elsewhere. The outcomes analyzed included surgical morbidity and mortality.

RESULTS

Twenty-six women and 19 men who ranged in age from 28 to 85 years (median, 69) were treated for colonic perforation. More than 80% of perforations occurred during the latter half of the study period because of the increased volume of colonoscopic procedures (8 perforations among 12,581 examinations from 1980 through 1987 versus 35 perforations among 44,447 colonoscopies from 1988 through 1995). Emergency laparotomy was performed in 42 patients (93%). Perforations occurred throughout the colon: right side = 10; transverse = 9; and left side = 23. Three patients without evidence of peritoneal irritation fared well with nonoperative management. Most patients underwent primary repair or limited resection in conjunction with end-to-end anastomosis. In 14 patients (33%), an ostomy was created. One patient underwent laparotomy without further treatment. Intra-abdominal contamination ranged from none (31%) to local soiling (48%) to diffusely feculent (21%). Postoperative complications occurred in 12 patients and were associated with older age (P = 0.01), large perforations (P = 0.03), and prior hospitalization (P = 0.04). No postoperative deaths occurred.

CONCLUSION

Despite a consistently low risk of colonic perforation, the increasing use of colonoscopy in our practice has resulted in an increased number of iatrogenic colonic perforations. In order to minimize morbidity and mortality, prompt operative intervention is the best strategy in most patients. Non-operative management is warranted in carefully selected patients without peritoneal irritation.