Risk factors of meconium-related ileus in very low birth weight infants: patients-control study.

Very low birth weight (VLBW) neonates experience various problems, including meconium-related ileus (MRI). This study investigated the risk factors of MRI and surgical MRI in VLBW infants. VLBW neonates admitted to the Neonatal Intensive Care Unit of Seoul National University Children's Hospital from October 2002 to September 2016 were included in the study. The diagnostic criteria for MRI were a decreased frequency of defecation with intolerable feeding, vomiting, and increased gastric residue (>50%); meconium-filled bowel dilatation in an imaging study; and no evidence of necrotizing enteritis or spontaneous intestinal perforation. Medical MRIs and surgical MRIs were managed through conventional treatment and surgical intervention. Of 1543 neonates, 69 and 1474 were in the patient and control groups, respectively. The risk factors for MRI include low birth weight (BW), cesarean section delivery, fetal distress, maternal diabetes, maternal hypertension, and maternal steroid use. Low BW and fetal distress were independent risk factors for MRI. Compared to the medical MRI group (n = 44), the risk factors for surgical MRI (n = 25) included males, younger gestational age, low BW, and meconium located at the small bowel. Male gender and low BW were independent risk factors for surgical MRI. Low BW and fetal distress were independent risk factors for MRI and male gender and low BW were independent risk factors for surgical MRI. In VLBW neonates, careful attention to the risk factors for MRI could minimize or avoid surgical interventions.

Sudden Infant Death After Vaccination: Survey of Forensic Autopsy Files.

Sudden infant deaths might be attributable to adverse reaction to vaccination, but separating them from coincidental occurrences is difficult. This study retrospectively investigated vaccination-related details and postmortem findings for 57 cases of sudden death in children 2 years or younger. Data were extracted from autopsy files at the Department of Forensic Medicine, Tokai University School of Medicine. Vaccination histories were available in 50 cases based on the maternity passbook. Of the 32 cases in which any vaccines were administered, 7 infants (21.9%) had received immunization within 7 days of death. The most frequent vaccine cited as the last immunization before death was Haemophilus influenzae B. Although a temporal association of vaccines with sudden death was present for two 3-month-old and one 14-month-old infants in whom death occurred within 3 days of receiving the H. influenzae type b and other vaccinations, a definitive relationship between the vaccine and death could not be identified. Histopathological examinations revealed pneumonia and upper respiratory infection as contributing to death in their cases. Moreover, all 3 cases showed hemophagocytosis in the spleen and lymph nodes, which are similar features to hemophagocytic lymphohistiocytosis. Judgment of the disorders as truly related to vaccination is difficult, but suspicious cases do exist. Forensic pathologists must devote more attention to vaccination in sudden infant death cases.

Unintended Consequences After Postoperative Ileus in Spinal Fusion Patients.

BACKGROUND: Postoperative ileus is not uncommon after spinal surgery. Although previous research has focused on the frequency of ileus formation, little has been done to investigate the clinical sequelae after development. We investigated the effect of postoperative ileus on patients' length of stay and rates of deep vein thrombosis (DVT) formation, myocardial infarction (MI), aspiration pneumonia, sepsis, and death. METHODS: The Healthcare Cost and Utilization Project National Inpatient Sample was queried to identify adult patients who underwent any spinal fusion procedure. Patient characteristics and outcomes for discharges involving spinal fusion surgery were compared between patients with and without postoperative ileus. The Rao-Scott χ2 test of association was used for categorical variables, and a t test for equality of means was used for continuous variables. Among discharges with postoperative ileus, a multivariate linear regression model was used to assess how fusion approach and fusion length were associated with length of hospital stay, controlling for sex, age, and race. RESULTS: A total of 250,221 patients were included. The mean length of stay was 3.75 days for patients without postoperative ileus and 9.40 days for patients with postoperative ileus. Patients with postoperative ileus are more likely to have DVT (4.1% vs. 20.8%, P < 0.001), MI (2.5% vs. 7.1%, P < 0.001), aspiration pneumonia (6.6% vs. 34.3%, P < 0.001), sepsis (5.7% vs. 35.7%, P < 0.001), and death (2.6% vs. 11.4%, P < 0.001). CONCLUSIONS: This study demonstrates that patients with postoperative ileus are significantly more likely to have DVT, experience MI, acquire aspiration pneumonia, develop sepsis, and die.

[Conservative and surgical ileus treatment]. / Konservative und operative Therapie des Ileus.

The diagnosis ileus is one of the most common indications for an emergency laparotomy. In 70% of the cases, the small intestine is affected, and in 30% it is the colorectum. While stuck hernias are a major cause in developing countries, the most common causes in western countries are postoperative adhesions that lead to an acute bowl obstruction. The timeframe for treatment of a complete mechanical obstruction is short as acute ischemia can lead to necrosis with bowl perforation within 6 h. The perioperative lethality for an emergency laparotomy due to an ileus ranges from 5-15%. In addition to the mechanical ileus, primary and secondary paralytic ileus is important in the differential diagnosis. As the genesis of postoperative ileus is multifactorial, a multimodal concept is required for successful treatment.

Associations of Specific Postoperative Complications With Outcomes After Elective Colon Resection: A Procedure-Targeted Approach Toward Surgical Quality Improvement.

Importance: Numerous quality initiatives have been implemented in an effort to minimize the onus of postoperative complications on clinical and economic outcomes after major surgery. It is unknown which complications have the greatest overall effect on these outcomes. Objective: To quantify the associations of specific postoperative complications with outcomes after elective colon resection. Design, Setting, and Participants: Patients undergoing elective colon resection between January 1, 2012, and December 31, 2013, who were included in the Colectomy-Targeted American College of Surgeons National Surgical Quality Improvement Program were assessed for the development of specific types of postoperative complications. The overall contributions of these complications to subsequent clinical and resource use outcomes were assessed. Main Outcomes and Measures: The main outcomes were 30-day mortality, end-organ dysfunction, reoperation, prolonged hospitalization, nonroutine discharge status, and hospital readmission. Risk-adjusted population attributable fractions were estimated for each complication-outcome pair. The population attributable fractions for a specific complication represented the percentage reduction in a given outcome that would be expected if exposure to that complication was completely eliminated. Results: A total of 26 682 patients undergoing elective colon resection were included for analysis; 13 870 patients were women (52.0%) and 15 088 (56.5%) were younger than 65 years. The most common index complications were ileus (n = 3140; 11.8%), bleeding (n = 2032; 7.6%), and incisional surgical site infection (n = 1873; 7.0%). Anastomotic leak was associated with the incidence of end-organ dysfunction, mortality, reoperation, and hospital readmission, with estimated population attributable fractions of 33.3% (95% CI, 29.6-36.8), 20.0% (95% CI, 14.0-25.7), 48.4% (95% CI, 45.7-51.0), and 20.6% (95% CI, 19.1-22.1) for each of these respective outcomes. The effect of complications, such as urinary tract infection, venous thromboembolism, and myocardial infarction, on these outcomes was comparatively small. Conclusions and Relevance: Anastomotic leak has a large overall effect on 30-day clinical and economic outcomes after elective colon resection. The findings of our study support the adoption of a procedure-targeted approach to surgical quality improvement and describe a practical method for assessing complication effect.

Ileus is a predictor of local infection in patients with acute necrotizing pancreatitis.

BACKGROUND & OBJECTIVES: Infected pancreatic necrosis (IPN) is associated with increased morbidity and mortality. Gut barrier dysfunction has been shown to increase the risk of bacterial translocation from the gut into the pancreatic bed. The primary aim of the study is to evaluate if ileus, a clinical marker of gut barrier dysfunction, can predict the development of IPN. METHODS: A retrospective cohort study of patients with necrotizing pancreatitis (NP) was conducted from 2000 to 2014. Ileus was defined as ≥2 of the following criteria: nausea/vomiting; inability to tolerate a diet, absence of flatus, abdominal distension and features of ileus on imaging. Extensive necrosis was defined as >30% nonenhancing pancreatic parenchyma on contrast-enhanced CT. Multivariable cox proportional hazard analysis was used to evaluate known and potential predictors of IPN. RESULTS: 142 patients were identified with NP, 61 with IPN and 81 with sterile necrosis. In comparison to a diagnosis of ileus documented in the medical chart, the ileus criteria had a sensitivity, specificity and positive and negative predictive value of 100%, 93%, 78% and 100%, respectively. On multivariate cox proportional hazard analysis, ileus [HR:2.6; 95%CI:1.4-4.9] and extensive necrosis [HR:2.8; 95%CI:1.3-5.8] were independently associated with the development of IPN while there was no association with bacteremia [HR:1.09; 95%CI:0.6-2.1]. CONCLUSION: Ileus in NP can be accurately defined using surgical criteria. Ileus is independently associated with the future development of IPN. Further studies will be needed to determine if ileus can serve as a clinical marker to direct therapeutic interventions aimed at reducing the incidence of IPN.

Procalcitonin in the recognition of complications in critically ill surgical patients.

BACKGROUND: Procalcitonin (PCT) is a relatively new, promising indirect parameter for infection. In the intensive care unit (ICU) it can be used as a marker for sepsis. However, in the ICU there is a need for reliable markers for clinical deterioration in the critically ill patients. This study determines the clinical value of PCT concentrations in recognizing surgical complications in a heterogeneous group of general surgical patients in the ICU. MATERIAL AND METHODS: We prospectively collected PCT concentration data from April 2010 to June 2012 for all general surgical patients admitted to the ICU. Both the relationships between PCT levels and events (diagnostic and therapeutic interventions) as well as between PCT levels and surgical complications (abscesses, bleeding, perforation, ischemia, and ileus) were studied. RESULTS: PCT concentrations were lower in patients who developed complications than those who did not develop complications on the same day, although not significant (P = 0.27). A 10% increase in PCT levels resulted in a 2% higher complication odds, but again this was not significant (odds ratio [OR], 1.020; 95% confidence interval [CI], 0.961-1.083; P = 0.51). Even a 20% or 30% increase in PCT concentrations did not result in higher complication probability (OR, 1.039; 95% CI, 0.927-1.165 and OR, 1.057; 95% CI, 0.897-1.246). Furthermore, an increase in PCT levels did not show an increase or a reduction in the number of diagnostic and therapeutic interventions. CONCLUSIONS: An increase in PCT levels does not help to predict surgical complications in critically ill surgical patients.

[Surgical treatment of acute large bowel ileus].

The results of treatment were analyzed in 47 patients, suffering operable cancer of left half of large bowel, complicated by an acute obturation ileus of the large bowel (AOILB), in whom radical obstructive operation of the Hartmann type was performed. In 26 patients (the 1-st group) a typical obstructive operation of Hartmann type was accomplished, and in 21 (2-nd group)--a radical obstructive operation in accordance to the method proposed. In a 1-st group postoperative complications have occurred in 7 (26.9%) patients, duration of stay in stationary was 19 days on average; in the 2-nd group the complications were observed in 2 (9.5%) patients. Duration of treatment in stationary was 13 days. Thus, application of the method of surgical treatment of the AOILB proposed have permitted to reduce postoperative morbidity rate in 2.8 times, the lethality--in 2.4 times, duration of a stationary treatment--in 1.4 times, necessity in postoperative wound dressing procedures and expenditure on dressing material--in 10 times.

A protocol of early aggressive acceleration of tube feeding increases ileus without perceptible benefit in severely burned patients.

Optimal nutrition is essential to the recovery of burned patients. The authors evaluated the efficacy of an aggressive nutrition delivery protocol. The following protocol was implemented: initiation of tube feeds within 4 hours, acceleration to goal rate within 8 hours, and tolerance of gastric residual volumes of 400 ml. Patients on the protocol formed the study group whereas patients admitted immediately before implementation served as controls for a study period of 7 days after admission. Outcome variables included ileus, prokinetic medication use, intensive care unit and overall length of stay, ventilator days and mortality. Variables were compared using bivariate analysis. The 42 study subjects and 34 controls were similar at baseline. Time to initiation was similar (6.8 vs 9.4 hours; P = .226), however, goal rate was achieved much sooner in the study group (11.2 vs 20.9 hours; P < .001). Number of hours spent at goal was different on days 1 and 2 (6.62 vs 2.74, P = .003 and 17.24 vs 13.18, P = .032) with no difference thereafter. Residual volumes in the study group were higher from day 2 onward, and remained increased throughout the study period (401 vs 234 ml average; P = .449). Clinical ileus was much more common in the study group (8 cases vs 1, P = .037). There was no difference in length of stay or mortality. The protocol was successfully implemented and resulted in early achievement of goal tube feed rates. However, this resulted in tube feed intolerance as manifested by more cases of clinical ileus.

Gallstone ileus: revisiting surgical outcomes using National Surgical Quality Improvement Program data.

BACKGROUND: Although surgical management remains the mainstay of therapy for gallstone ileus, the optimal approach--enterolithotomy alone or combined with biliary-enteric fistula disruption--is controversial because of the reliance on small single-center series to describe outcomes. Using the American College of Surgeons' National Surgical Quality Improvement Program database, we sought to (1) review the outcomes of patients undergoing surgical management of gallstone ileus and (2) determine if cholecystectomy in addition to enterolithotomy increased morbidity or mortality rate. METHODS: We analyzed the demographics, comorbidities, acuity, operative time, postoperative hospitalization length, and 30-d morbidity and mortality rates of 127 patients from 2005 to 2010 who underwent a procedure for the relief of gallstone ileus. We identified a subset of 14 patients who underwent simultaneous cholecystectomy. We compared the "no cholecystectomy" and "cholecystectomy" groups using standard statistical methods. RESULTS: The overall 30-d postoperative morbidity and mortality rate was 35.4% and 5.5%, respectively. Superficial surgical site infection and urinary tract infection were the most common complications. There was no significant difference in mortality rate between the no cholecystectomy and the cholecystectomy groups (5.3% versus 7.1%, respectively; P = 0.78), but the latter group did experience more minor complications, longer operations, and longer postoperative hospitalization. CONCLUSIONS: Other recent studies on this topic have collected data or reviewed literature across several decades, making this study in particular one of the largest truly modern series. Perhaps reflecting changes in perioperative management, surgical treatment of gallstone ileus is less morbid than previously described, but there is still insufficient evidence to favor concurrent cholecystectomy.

[Colorectal tumor surgery in the elderly: results of quality assurance]. / Kolorektale Tumorchirurgie beim Hochbetagten: Ergebnisse der Qualitätssicherung.

The age group ≥ 80 years has become of great importance in the surgical treatment of colorectal cancer due to the demographic changes over the years. To assess patient risk, early postoperative and oncologic long-term outcome 64,740 patients with colorectal cancer were enrolled in various nationwide multicenter observational studies through two study periods (2000-2004 and 2009-2011) and analyzed according to various age groups, in particular ≥ 80 years. The percentage of octogenarians increased from 2009 to 2011, which was associated with an increased patient risk. In 70  % of patients ≥ 80 years old the operative risk was preoperatively classified as ASA stages III and IV. There was a high age-independent resection rate of colon cancer; however, the rectal cancer resection rate in octogenarians was significantly lower. In the age group ≥ 80 years there was a relatively high rate of emergency surgical interventions because of an ileus due to tumor-induced lumen obstruction leading to a hospital mortality rate in both study periods of 18.8 % and 17.9 %, respectively. In the octogenarians there were more locally advanced colon cancer lesions of stage T3/4 but less tumor lesions with distant metastases. The age-corrected tumor-free 5-year survival rate of the octogenarians with colon cancer of tumor stage UICC I-III was identical to that of younger patients.

[Prevention of small bowel fistulas during open abdominal treatment: lessons learned]. / Prävention von Dünndarmfisteln beim Laparostoma: Lessons learned.

BACKGROUND: Abdominal vacuum therapy has simplified the treatment of a laparostoma. But is that all that it can achieve? The role of abdominal vacuum therapy concerning the development of small bowel fistulas is still under discussion. Treatment of the bowel surface seems to be crucial for the prevention of fistulas. As military surgeons, we need a simple, standardised regimen, leading to reproducible good results and low complication rates. The question is: are we able to eliminate small bowel fistula during open abdominal treatment? PATIENTS AND METHODS: We analysed 28  consecutive patients with open abdominal treatment in the period of 2004 to 2009. From June 2006 on, we implemented an algorithm, using the KCI V.A.C.® Abdominal Dressing (Kinetic Concepts Inc., San Antonio, Texas, USA) and a vicryl mesh between the non-adherent layer and the foam to prevent fascial retraction. The patients treated -after the installation of the new algorithm were compared to a group treated from 2004 to May 2006 before its installation. Fistula rates, mortality, the fascial closure rate, the number of abdominal dressing changes and the duration of open -abdominal treatment were evaluated. RESULTS: After implementation of our new algorithm, the fistula rate decreased from 45 % to 0 %. The mortality during open abdominal treatment decreased from 45 % to 6 %. In addition, the duration of open abdominal treatment was reduced as well as the number of dressing changes. The primary fascial closure rate was 87 %. CONCLUSION: We implemented a regimen, which is suitable for our mission in Afghanistan, as well as for medical evacuation and for the treatment of patients in our hospitals in Germany. It ensures a standardised treatment of the open abdominal cavity with an ideal protecting treatment of the bowel surface. Our algorithm utilises the advantages of the laparostoma while minimising the complications. The development of a small bowel fistula was eliminated in the evaluated patient group and mortality was clearly reduced.

Gallstone ileus: analysis of eight cases and review of the literature.

OBJECTIVE: We hereby analyzed a series of gallstone ileus cases operated on in our department starting from a Bouveret syndrome case. METHOD: Retrospective analysis of all gallstone ileus cases who underwent surgery in our department during the last 26 years. We took into consideration diagnostic elements, time from admission to surgery, type of surgery and post-operative outcome. RESULTS: During this period 9,143 gallstones were deferred to surgery; 27 biliary-digestive fistulae were discovered during surgery; gallstone ileus complicated fistula in 8 patients. Gallstone ileus was exclusively present in elderly women with associated comorbidities. Diagnosis was suggested by clinical features of acute or incomplete intestinal obstruction; it was sustained by imagistic studies with different degrees of relevance. The average time from admission to surgery was 2.6 days. Surgical approach varied from simple enterolithotomy to additional fistula repair. The outcome was uneventful in most of the cases with only one exception. CONCLUSIONS: gallstone ileus is a rare condition, occurring in elders with important comorbidities. The choice for surgical procedure depends on the obstructive syndrome's gravity and associated comorbidities; the type of intervention does not significantly influence post-operative morbidity and mortality rates.

Gallstone ileus--clinical and therapeutic aspects.

Gallstone ileus represents a rare (0.3-0.5%), but serious complication of a common illness--the gallbladder lithiasis and the incidence of this fascinating disease has remained the same over the years. The main actual characteristics of this pathology are the age over 65, the female gender (men/women ratio 1/5:1:10--due to the high rate of vesicular lithiasis) and the under 50% diagnostic established preoperatively. The frequency of gallstone ileus recurrence is of 4,7-5%. In this article, we discuss the pathogenesis of this illness presenting all the mechanisms described in the medical literature. The Rigler triad found at the abdominal CT-scan generally established the diagnosis. Still, in 25% of the cases we have a misdiagnosis because of the underestimation of the size of the gallstone. Finally, the treatment of gallstone ileus has had major changes from the past. We described the endoscopic and laparoscopic approach, which represents the modern treatment of this disease. Despite these diagnostic and therapeutic possibilities, the mortality remains high and the common causes are associated comorbidities and late presentation to the physician.

Outcomes of intestinal failure--a comparison between children with short bowel and dysmotile intestine.

BACKGROUND: We investigated whether mortality, intestinal adaptation, and liver function differ between intestinal failure (IF) patients with either short bowel (SB) or bowel dysmotility (DM). PATIENTS AND METHODS: Twenty-six consecutive patients with SB (n = 20) or DM (n = 6) treated between 2000 and 2007 were retrospectively assessed. Intestinal failure was defined as less than 25% of age-adjusted small intestinal length or dependence on parenteral nutrition (PN) more than 6 months. RESULTS: Median age-adjusted small intestinal length (17% vs 45%) and gestational age (35 vs 40 weeks) were (P < .05) shorter, whereas proportion of the remaining colon (86% vs 0%) was (P < .05) higher in the SB group relative to the DM group. Overall survival was 92%. Median peak serum bilirubin (80 vs 25 micromol/L) and rate of cholestasis (11/20 vs 0/6) were higher (P < .05) in the SB group. Short bowel rather than DM as an etiology of IF predicted weaning off PN (RR, 39.3; 95% confidence interval [CI], 1.43-526; P < .01) and development of cholestasis (risk ration [RR], 18.3; 95% CI, 0.658-127; P < .05). Three SB children developed liver failure and two died, whereas neither of these occurred in the DM group. CONCLUSIONS: Children with SB are more likely to wean off PN but more prone to cholestatic liver disease than those with DM as an etiology of IF.

[Efficacy of jejunotransversoanastomosis in treatment of conglomerate forms of adhesive ileus].

The results of the surgical treatment of 175 patients with conglomerate forms of adhesive ileus are analyzed. The bypass jejuno(ileo)transversoanastomosis was necessitated in 79 patients. This allowed decrease the rate of postoperative complications and lethality. 31 patients were subjected to the long-term follow-up. Good and satisfactory results were achieved in 93,5% of operated patients.

Primary resection and anastomosis for complicated meconium ileus: a safe procedure?

Various options are available for the surgical treatment of meconium ileus (MI). This paper examines the use of resection and primary anastomosis as the favoured option for the treatment of complicated meconium ileus. This was a retrospective study. All patients (13 children) with MI treated with primary resection and anastomosis (RA) in the 10-year period (1996-2005) at St Mary's Hospital in Manchester were identified. The case notes were retrieved. The gestational age, type of surgery, length of bowel resection and complications were recorded. Out of 13 (3 males, 10 females), 7 had severely dilated bowels, 5 had perforation and 1 had volvulus. Mean length of bowel resection was 33.8 cm (range 20-50 cm). Overall survival in this group was 85%. Seven patients (54%) developed complications. Four (31%) had surgical complications: two anastomotic strictures with adhesions, one adhesive intestinal obstruction and one intra-abdominal drain retraction. Primary resection and anastomosis is a safe option in the treatment of complicated meconium ileus. It has the advantage of less hospital stay and avoids a secondary laparotomy for closure of the stoma.

[The significance of intestinal decompression and lavage in the treatment of ileus and peritonitis].

The results of treatment of 67 patients, admitted to the hospital clinic for the spread peritonitis and ileus were studied. In 37 of them (main group) the intestinal decompression and hypothermic lavage was performed, in 30 (control group)--intestinal decompression only. The operation character and intensive therapy volume in patients of both groups were similar. In conduction of hypothermic intestinal lavage the accelerated restoration of intestinal peristalsis was noted, as well as the peritonitis and intoxication symptoms elimination. Duration of treatment of patients in stationary in the main and control groups had constituted, accordingly (11.6 +/- 0.73) and (16.8 +/- 1.03) days, lethality--8.1 and 13.8, frequency of complications--10.8 and 30%.

Survival and complication rates in 300 horses undergoing surgical treatment of colic. Part 2: Short-term complications.

REASONS FOR PERFORMING STUDY: Few studies have assessed short- and long-term complication rates of horses following surgical treatment of colic, a potentially fatal condition. Complications can lead to patient discomfort and increased costs; knowledge of predisposing factors may help to reduce complication rates. OBJECTIVES: To document and analyse short-term complications in 300 horses undergoing colic surgery, and to assess some of the possible predisposing factors. METHODS: History, clinical findings, surgical findings and procedures, and post operative treatments of 300 consecutive surgical colic cases (1994-2001) were reviewed. Comparisons among groups of discrete data were made using chi-squared or Student's t tests as appropriate. RESULTS: Short-term complications in 227 horses following a single laparotomy included colic/pain (28.2%), incisional drainage or infection (26.9%), post operative ileus (13.7%), severe endotoxaemic shock (12.3%), jugular thrombophlebitis (7.5%), septic peritonitis (3.1%) and colitis/diarrhoea (2.2%). Horses with small bowel obstruction had a higher rate of post operative ileus than those with large bowel obstruction. Rates of post operative pain and shock were higher in horses with small colon rather than large colon obstruction, and in those that had an ischaemic rather than a simple obstruction. The rate of wound complications increased with increasing total plasma protein concentration at admission. Horses that had a repeat laparotomy had a higher rate of wound complications compared to those that had a single laparotomy. Application of a stent bandage was associated with a higher rate of wound complications than if no stent was applied; however, application of an incise drape over the wound for recovery was associated with a lower rate of wound complications than for horses that had no protective covering of the wound. CONCLUSIONS: The most common short-term post operative complications following colic surgery were pain, incisional drainage, ileus, endotoxaemiac shock and jugular thrombophlebitis. Some factors that appeared to predispose to these complications were identified. Although many of these factors related to the underlying disease process, a number of factors, including surgical techniques, were identified that might be amenable to modification. POTENTIAL RELEVANCE: Prospective studies to assess the effects of modifying these factors on survival rates should be performed.