Mechanical inhibition of angiogenesis at the saphenofemoral junction in the surgical treatment of varicose veins: early results of a blinded randomized controlled trial.

BACKGROUND: Saphenofemoral junction (SFJ) ligation has been a major component of surgical intervention for varicose veins; however, recurrence occurs in as many as 40%. Neovascularization with reconnection of the venous channels at the transected SFJ has been identified as the major cause of this recurrence. This randomized controlled study sought to evaluate mechanical suppression of neovascularization at the SFJ, with the use of a synthetic patch, to prevent recurrence after ligation surgery. METHODS AND RESULTS: A total of 389 limbs (from 292 patients) were randomized into either control (SFJ ligation surgery) or patch (SFJ ligation with polytetrafluoroethylene patch of the transected SFJ) groups. All patients underwent clinical assessment, duplex imaging, and air plethysmography studies preoperatively and at 1, 6, 12, and 36 months postoperatively. The patch consistently halved the recurrence rate to 3 years postoperatively in all clinical subgroups. In those patched SFJs that still developed recurrence, evidence of neovascularization circumventing the polytetrafluoroethylene patch was observed by both ultrasound and histology. CONCLUSIONS: This study demonstrates that use of a polytetrafluoroethylene patch is an effective mechanical suppressant of neovasculogenesis at the SFJ and can be safely used as a strategy to improve long-term outcome of varicose vein surgery.

American Society of Anesthesiologists classification of physical status as a predictor of wound infection.

BACKGROUND: Wound infection occurs when bacterial contamination overcomes the hosts' defences against bacterial growth. Wound categories are a measurement of wound contamination. The American Society of Anesthesiologists (ASA) classification of physical status may be an effective indirect measurement of the hosts' defence against infection. This study examines the association between the ASA score of physical status and wound infection. METHODS: A retrospective review of a prospective study of antibiotic prophylaxis was carried out. Patients with a documented ASA score who received optimal prophylactic antibiotics were included. The anaesthetist scored the ASA classification of physical status in theatre. Other risk factors for wound infection were also documented. Patients were assessed up to 30 days postoperatively. RESULTS: Of 1013 patients there were 483 with a documented ASA score. One hundred and one may not have received optimal prophylaxis, leaving a database of 382 patients. There were 36 wound infections (9.4%). Both the ASA classification of physical status (P = 0.002) and the wound categories (P = 0.034) significantly predicted wound infection. The duration of surgery, patient's age, acuteness of surgery and the organ system being operated on did not predict wound infection. On logistic regression analysis the ASA score was the strongest predictor of wound infection. CONCLUSION: When effective prophylactic antibiotics were used the ASA classification of physical status was the most significant predictor of wound infection.

Accuracy of the surgeons' clinical prediction of perioperative complications using a visual analog scale.

BACKGROUND: The ability to predict who will develop perioperative complications remains difficult because the etiology of adverse events is multifactorial. This study examines the preoperative and postoperative ability of the surgeon to predict complications and assesses the significance of a change in prediction. METHODS: This was a prospective study of 1013 patients. The surgeon assessed the risk of a major complication on a 100-mm visual analog scale (VAS) immediately before and after surgery. When the VAS score was changed, the surgeon was asked to document why. Patients were assessed up to 30 days postoperatively. RESULTS: Surgeons made a meaningful preoperative prediction of major complications (median score = 27 mm vs. 19 mm, p < 0.01), with an area under the receiver operating characteristic curve of 0.74 for mortality, 0.67 for major complications, and 0.63 for all complications. A change in the VAS score postoperatively was due to technical reasons in 74% of stated cases. An increased VAS score identified significantly more complications, but the improvement in the discrimination was small. When included in a multivariate model for predicting postoperative complications, the surgeon's VAS score functioned as an independent predictive variable and improved the predictive ability, goodness of fit, and discrimination of the model. CONCLUSIONS: Clinical assessment of risk by the surgeon using a VAS score independently improves the prediction of perioperative complications. Including the unique contribution of the surgeon's clinical assessment should be considered in models designed to predict the risk of surgery.

Using cost of infection as a tool to demonstrate a difference in prophylactic antibiotic efficacy: a prospective randomized comparison of the pharmacoeconomic effectiveness of ceftriaxone and cefotaxime prophylaxis in abdominal surgery.

The purpose of this study was to test the hypothesis that cost, as well as frequency of infection, could be used to demonstrate a difference in the performance of prophylactic antibiotics. In a prospective, randomized, double-blind study, 1013 patients undergoing abdominal surgery were given 1 g of intravenous ceftriaxone (R) or cefotaxime (C) at induction of anesthesia, and an additional 500 mg of metronidazole for colorectal surgery. Infection was checked for during the hospital stay and at 30 days postoperatively. The inpatient, outpatient, and community costs of infection were prospectively collected. The frequency of wound infection for appendectomies when additional metronidazole was not administered was greater with cefotaxime (R 6%, C 18%, p < 0.05), but the cost of infection was the same (average cost R $994 +/- SD $1101, C $878 +/- $1318). For all other procedures, the frequency of wound infection was similar (R 8%, C 10%), but the cost was less with ceftriaxone (R $887 +/- $1743, C $2995 +/- $6592, p < 0.05). Ceftriaxone decreased the frequency but not the cost of chest and urinary infection (frequency R 6%, C 11%, p < 0.02, cost R $1273 +/- 2338, C $1615 +/- 4083). Differences in both the frequency and cost of all infection are also presented. Ceftriaxone decreased either the frequency or the cost of different postoperative infections. The cost of infection can increase the discriminatory power of trials comparing antibiotic effectiveness.

A comparison of the prophylactic efficacy of ceftriaxone and cefotaxime in abdominal surgery.

BACKGROUND: Although ceftriaxone (R) and cefotaxime (C) are highly effective antibiotics, few studies have directly compared their prophylactic efficacy. METHODS: In a prospective, randomized, double blind study of 1,013 patients undergoing abdominal surgery, the prophylactic use of ceftriaxone and cefotaxime were compared. Intravenous cephalosporin, 1 g, was given at induction of anesthesia, with intravenous metronidazole, 500 mg, also being given for colorectal surgery. RESULTS: The difference in wound infection (R 8%, C 12%, P <0.05) was due to appendicectomies not receiving metronidazole, (R 6%, C 18%, P <0.03) and was no longer present when these cases were excluded from analysis (R 8%, C 10%). Of note chest and urinary tract infection (R 6%, C 11%, P <0.02) and "any" infection (R 20%, C 27%, P <0.05) were reduced with ceftriaxone. CONCLUSIONS: Both antibiotics provide comparable wound prophylaxis as long as metronidazole is added for colorectal and appendiceal surgery. Ceftriaxone may be more versatile having the additional apparent benefits of reducing other postoperative infections, being less dependent on metronidazole as an adjunct and providing a more effective prophylactic cover against Staphylococcus aureus.