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Clinical pathways are similar to the production algorithms developed by industry. They are being adapted for use in healthcare to reduce resource utilization, decrease variability, and control expenditures. At Boston Medical Center we identified four trauma diagnoses that we believed to be amenable to the design and implementation of clinical pathways: closed head injury, penetrating wound to the abdomen, penetrating wound to the chest, and penetrating wound to an extremity. Upon implementation of these pathways, appropriate nonoperative, single-system, short-stay trauma patients were enrolled in them. This article details the process by which the four diagnoses were identified and the pathways designed, implemented, and evaluated. Preliminary data demonstrate a significant decrease in resource utilization following implementation of the pathways, without an adverse impact on readmission rates, length of stay, or mortality.

Gallbladder carcinoma is an uncommon, but highly fatal disease. Its symptoms frequently mirror those of gallstone disease, and in most instances, diagnosis is an incidental finding at surgery. While risk factors have been suggested for this cancer, many may in reality simply be a consequence of the older age of the population. This study is one of the few to approach this question by using a case-control study design comparing gallbladder carcinoma patients with a gallstone population, coupled with multivariate analysis to determine age-independent risk factors. Univariate analyses showed gallbladder carcinoma patients to be older than gallstone patients and to have many age-associated diseases. Following multiple regression adjustment for age, this disease was associated with female gender and with a previous history of gallstone symptoms. Carcinoma patients were less likely to have cholesterol gallstones in their gallbladders at surgery. A previous history of smoking was a substantial risk but of borderline statistical significance. Previous studies report associations that may be due to the older age of the gallbladder carcinoma patient. Our results show that after adjusting for age with multivariate analysis, gallbladder cancer subjects were predominantly female, more likely to report previous gallstone symptomology, and to smoke. While gallstones were not universally isolated from carcinoma patients at cholecystectomy, when present, they were less frequently classified as cholesterol gallstones based on visual inspection. Further cohort studies which target these populations will allow us to gain a more solid consensus on the risk factors for this disease.

Epidemiological studies have provided conflicting information about the relationship between fat consumption and gallstone formation. We studied cholesterol gallstone formation in prairie dogs after 1 wk of the following diets: (group A) a control diet with no added cholesterol and 5% of calories from corn oil, (group B) 1.2% cholesterol with 5% of calories from corn oil or (group C) 1.2% cholesterol with 40% of calories from corn oil. In controls serum cholesterol was 58.9 +/- 4.5 mg/dl, gallbladder bile was unsaturated with cholesterol (cholesterol saturation index = 0.7 +/- 0.1; cholesterol = 3.8 mmol/L) and none of 12 animals formed cholesterol crystals or stones. The low-fat diet supplemented with cholesterol (group B) increased serum and biliary cholesterol concentrations to 292 +/- 76 mg/dl and 7.5 +/- 1.1 mmol/L, respectively (p0.05), but cholesterol saturation index was only modestly increased (1.1 +/- 0.1) and in only one of eight animals did cholesterol monohydrate crystals develop. Group C, animals, which received cholesterol plus high levels of corn oil, had higher serum cholesterol levels (457 +/- 66 mg/dl), higher biliary cholesterol concentrations (16.6 +/- 1.3 mmol/L), higher cholesterol saturation indexes (1.7 +/- 0.1) and increased incidence of cholesterol gallstones (5 of 11). The two cholesterol-supplemented diets increased biliary phospholipid concentrations, decreased the ratio of cholic/chenodeoxycholic acid and increased the proportion of biliary lecithins containing linoleic acid, but these abnormalities were greatest in group C, which was given large amounts of corn oil. These findings suggest that cholesterol gallstone formation in the prairie dog is accelerated by increased dietary omega-6 polyunsaturated triglycerides.

Risk factors for postoperative wound infection in patients undergoing vascular surgery may include age, comorbid conditions, wound classification, use of prosthetic grafts, and repeat operations. Groin incisions, in particular, pose substantial risk during placement of prosthetic grafts.To investigate the role of infected inguinal lymph nodes (LN) in groin wound infection (GWI), we excised an inguinal LN from 69 consecutive patients (89 groins) undergoing 36 infrainguinal reconstructions, 24 aortobifemoral bypasses, 12 extra-anatomic femoral bypasses, 11 vein stripping, and 6 femoral pseudoaneurysm repairs. LN Gram staining was performed, and aerobic and anaerobic cultures were obtained. In addition cultures were taken from any ulcerated or gangrenous lesion on the ipsilateral open extremity lesion.Bacteria were isolated from 10 of 89 LN (11.2%) and included Staphylococcus species, gram-negative rods, diphtheroids, and Peptostreptococcus. Three of the 10 LN were taken from extremities with open lesions; seven were not. In no case did organisms cultured from a groin LN correlate with its corresponding open extremity lesion. Four GWI developed after operation (4%). In each case results of the groin LN cultures were negative. Three of the GWI were associated with an ulcerated or gangrenous lesion on the ipsilateral extremity (p = 0.08, odds ratio = 7.6), but in only one case did the organisms from the GWI correspond to that in the open lesion. The development of a GWI was strongly associated with insulin-dependent diabetes mellitus (p = 0.009, odds ratio = 22.9).In conclusion, 11% of groin LN harbored bacteria, but none of these were associated with subsequent development of a wound infection. Instead, insulin-dependent diabetes mellitus and the presence of an open skin lesion on the ipsilateral extremity seemed to be associated with an increased risk of wound infection.

The development of an objective, noninvasive method to assess the hemodynamic effects of venous surgery has long been awaited. Previous methods used to evaluate the results of surgery for varicose veins and venous stasis ulceration have been limited in their quantitative assessment. Now, by use of air plethysmography (APG), we can accurately quantify the effectiveness of corrective venous surgery. Twenty-five extremities that had evidence of venous insufficiency were examined with use of APG before and after venous surgical procedures. Surgery was directed at specific sites of venous incompetence as defined by physical examination and high-resolution duplex imaging. Twenty-one extremities underwent ligation and stripping of the greater saphenous vein. In these patients, APG showed an improvement in venous reflux as demonstrated by a decrease in the venous filling index from 6.6 +/- 0.7 ml/sec to 1.8 +/- 0.3 ml/sec (p = 0.0001) and venous volume from 177.1 +/- 14.5 ml to 139.2 +/- 8.9 ml (p = 0.0008). In addition, these patients showed a mild improvement in calf muscle pump function as noted by an improvement in ejection fraction from 45.8 +/- 2.0% to 50.8% +/- 2.5% (p = 0.07). The residual volume fraction decreased from 45.0% +/- 3.4% to 42.0% +/- 3.7%, a difference that was not statistically significant (p = 0.4). Four extremities with grade III chronic venous insufficiency underwent popliteal vein valve transplantation with use of an autogenous axillary vein valve.(ABSTRACT TRUNCATED AT 250 WORDS)

Fluid resuscitation and transfusion therapy are particularly critical in patients undergoing extensive vascular operations because of diffuse atherosclerosis and the risk of perioperative myocardial infarction. Sophisticated perioperative monitoring has reduced the mortality rate substantially, but indications for transfusion remain controversial. We determined erythrocyte volume, (EV), total blood volume (TBV) and plasma volume (PV) preoperatively and 18 to 24 hours postoperatively in 41 elderly patients (68.8 +/- 1.3 years) undergoing elective vascular operations (30 abdominal aortic aneurysmorrhaphy, ten aortofemoral bypass and one carotid endarterectomy). EV was measured using 51chromium-labeled autologous erythrocytes; TBV and PV were calculated from EV and total body hematocrit (peripheral venous hematocrit [HCT] x 0.89). Ideal blood volumes were calculated from nomograms based on body surface area and gender. Relationships between body volumes (percentage of ideal), simultaneously measured peripheral venous HCT and hemodynamic parameters heart rate, mean arterial pressure, central venous pressure, pulmonary capillary wedge pressure, cardiac index and systemic vascular resistance index were studied by stepwise regression. In 24 patients, blood volumes and hemodynamic parameters were also measured in the recovery room. HCT significantly correlated with EV at all three time periods (p less than 0.001), but the ability of HCT to predict EV in an individual patient was relatively poor (r = 0.50 preoperatively; r = 0.54 in recovery room and r = 0.66 24 hour postoperatively). By 24 hours postoperatively, EV had decreased to 78.3 +/- 2.4 percent of ideal EV (range of 47 to 112 percent). However, only two patients had HCT less than 30 despite the fact that 13 of 41 patients had an EV deficit of greater than 30 percent. No patient had a HCT of less than 25 percent. Hemodynamic parameters did not contribute to the prediction of EV, PV or TBV at any time. Two patients had myocardial infarctions postoperatively associated with 24 hour EV deficits of 18.5 and 29.6 percent. One patient died of a pulmonary embolus. Because of these findings, the concept of a "transfusion trigger" must be viewed with caution, since many patients undergoing vascular operations will have considerable EV deficits despite an "acceptable" HCT.

Leg ulcers caused by chronic venous insufficiency plague an estimated 500,000 Americans, but there have been few improvements in conservative treatment in this century, and Unna's boot continues to be a mainstay of therapy. A recent report suggests that Duoderm CGF dressing provides greater patient comfort and enhanced compliance, but Duoderm alone (without compression) resulted in slower healing compared with Unna's boot. We enrolled 30 patients (30 ulcers) in a clinical trial to compare Duoderm CGF plus compression (Coban wrap) to Unna's boot. No significant difference was observed between the two groups with respect to age, sex, initial ulcer area, ulcer duration, or extent of venous insufficiency by duplex scan. Eight of 16 ulcers (50%) in the Duoderm group healed completely versus 6 of 14 ulcers (43%) in the Unna's boot group (p = 0.18). Healing rates (square centimeters per week) correlated significantly with initial ulcer area and initial ulcer perimeter for both groups but best correlated with initial ulcer perimeter (r = 0.88 with Duoderm, p less than 0.0001; r = 0.80 with Unna's boot, p less than 0.002). After adjusting for differences in initial ulcer perimeter, healing rates were significantly faster for patients on Duoderm than patients on Unna's boot during the first 4 weeks of therapy (0.384 +/- 0.059 cm2/wk/cm perimeter for Duoderm versus 0.135 +/- 0.043 cm2/wk/cm perimeter for Unna's boot; p = 0.002). At 12 weeks patients on Duoderm again appeared to heal faster than those on Unna's boot, although the result did not reach statistical significance (0.049 +/- 0.007 cm2/wk/cm perimeter for Duoderm versus 0.020 +/- 0.017 for Unna's boot, p = 0.11).(ABSTRACT TRUNCATED AT 250 WORDS)

Valvular incompetence associated with venous ulceration can occur in the superficial, deep, or perforating systems. Duplex imaging was used to evaluate 95 extremities (78 patients) with current venous ulceration to determine the location of incompetence in each extremity. In addition, in 91 of the 95 extremities the area of the venous ulcer was evaluated for the presence of perforating veins or any other superficial veins or both conditions. Sixty-three (66.3%) of the 95 extremities had multisystem incompetence (superficial and perforating plus superficial and deep plus perforating and deep plus superficial and perforating and deep), whereas single system incompetence (superficial plus perforating plus deep) was seen in only 26 (27.3%). Isolated deep incompetence was identified in only two extremities (2.1%). Furthermore, 45% (41/91) of the ulcers had no duplex evidence of any venous abnormality in the ulcer bed. These data show that the site of valvular incompetence occurred in multiple locations, that isolated valvular incompetence of the deep venous system was uncommon, and that perforating veins were not always in the ulcer bed itself. Because standard venous surgery has traditionally been directed toward only one system, this may provide one explanation for ulcer recurrence. Therefore complete venous evaluation with duplex imaging allowing for surgical intervention directed specifically to the sites of involvement in each system is recommended.

The purpose of this study was to evaluate duplex imaging as a means of assessing perforating veins in patients with longstanding venous stasis ulceration. Thirty patients with nonhealing venous stasis ulcers and twenty normal volunteers serving as controls were evaluated with a standard 8-MHz imaging probe and integrated pulsed Doppler. The internal diameter of perforating veins was measured and perforators were grouped into one of four categories based on functional criteria: competent perforator with venous flow (C); incompetent perforator with venous flow (IC); competent perforator with arteriovenous flow (C-AVC); incompetent perforator with arteriovenous flow (IC-AVC). Sixteen of the patients with ulcers were subsequently studied by ascending venography and in 11 patients, intraoperative identification of perforating veins was made during the Rob procedure. In this subset of patients the vessel was categorized as competent or incompetent regardless of flow signal. There were significant differences in mean perforator diameter between ulcer patients and normal volunteers. Duplex imaging identified 93 perforators and venography a total of 70. In all 16 extremities, duplex imaging made the diagnosis of significant perforating vein incompetence, verified by venography. Intraoperative findings demonstrated an excellent correlation with duplex imaging. We believe duplex imaging to be a promising new modality for evaluation of the perforating veins of the lower extremity.

The recording and reporting of resident operative experience have become increasingly important tasks for surgical training programs, and computerized data bases are now being used for these purposes. Despite their usefulness, these computerized systems can impose significant burdens in terms of manpower, time, and cost, particularly if the program director is to track diligently each resident's progress at intervals. Described here is a simple, inexpensive method for recording and reporting resident operative experience. This system can be maintained on a microcomputer with any one of a number of inexpensive, commercially available data base programs.

During the past century, a variety of explanations have been proposed to explain the pathogenesis of cholesterol gallstones. Early attempts to account for the phenomenon of cholelithiasis focused on events in the gallbladder and stressed mucosal inflammatory changes, gallbladder stasis, stratification of bile, and absorption of bile salts from a damaged mucosa. The advent of the concept of "lithogenic bile" redirected attention to the liver and led to the proposal that an enzyme-mediated genetic and/or metabolic defect is the initiator of cholesterol cholelithiasis. While recognizing that the pathogenesis of gallstones is probably multifactorial, alterations in gallbladder and biliary ductal motor function constitute a plausible, but as yet unexplored, mechanism for alterations in enterohepatic circulation dynamics and subsequent cholesterol cholelithiasis. Gallbladder motor function is a complex phenomenon influenced by dynamic compliance, autonomic pharmacology, hormonal responses, and sphincter dynamics. Attempts to describe these aspects of biliary physiology may characterize the next phase in our understanding of the pathogenesis of cholesterol cholelithiasis.

Increased synthesis of prostaglandins in the wall of the gallbladder may play a role in the pathogenesis of cholesterol gallstones by mediating mucus hypersecretion and thereby accelerating nucleation and the precipitation of cholesterol-supersaturated bile. We induced gallstones in prairie dogs and guinea pigs by feeding a cholesterol-supplemented diet for periods as long as 6 weeks. Gallbladder prostaglandin synthesis was quantitated by specific radioimmunoassays that measured the amount of various prostanoids released from the gallbladder during in vitro incubation. The gallbladders of cholesterol-fed prairie dogs showed increased synthesis of prostaglandin E2, prostaglandin F2a, and thromboxane and increased concentrations of glycoprotein in gallbladder bile. These changes were evident as early as 2 weeks after institution of the cholesterol diet, although cholesterol gallstones did not form until 4 or more weeks. In contrast, cholesterol feeding of the guinea pig did not induce cholesterol supersaturation. In this species pigment gallstones formed, probably as a result of a cholesterol-induced hemolytic anemia, and gallbladder mucus hypersecretion did not occur. Pigment gallstone formation in the guinea pig was associated with an increase in prostacyclin synthesis, but the synthesis of prostaglandin F2a and thromboxane was decreased. Increased prostaglandin synthesis may contribute to the formation of cholesterol gallstones but does not appear to participate in pigment gallstone formation.