Effect of 2% Chlorhexidine Gluconate-Impregnated Cloth on Surgical Site Infections in Vascular Surgery.

BACKGROUND: Surgical site infections (SSIs) are a significant burden to patients and health care systems. This retrospective study evaluates the observed rates of SSI after our institution implemented chlorhexidine gluconate-impregnated (CHG) cloth as a preoperative antiseptic preparation in elective vascular surgery. METHODS: Between March 2011 and January 2012, we reviewed 250 patients who underwent elective vascular surgery who used the CHG cloth preoperatively. Their rate of SSIs was compared with 252 control patients who received the CHG shower preoperatively during the preintervention period. Urgent and emergent cases were excluded. The primary outcome measured was SSI within 30 days of index operation. RESULTS: There was no baseline difference in mean age, gender distribution, smoking status, diabetes, chronic obstructive pulmonary disease, and the number of patients with body mass index >40 between the cohorts. There was no difference in the overall rate (5.6% vs. 5.6%, P = 1.00) and type of SSIs between the 2 groups, but the control group trended toward deeper infections (4 deep incisional and 2 organ space vs. none and 1, respectively). The control group also had more dirty or infected wound categories (10 vs. 21.4%, P < 0.01) and more perioperative antibiotic errors and hypothermia (P < 0.02). CONCLUSIONS: There was no observed difference in SSI rates before and after implementation of the CHG as the preoperative method of skin decontamination in our retrospective case-control cohorts.

Comparing Nonrandomized Observational Studies With Randomized Controlled Trials in Cervical Disc Arthroplasty: A Meta-analysis.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: To compare the treatment effects of observational studies versus randomized controlled trials (RCTs) in cervical disc arthroplasty. SUMMARY OF BACKGROUND DATA: RCTs can be logistically challenging and sometimes insufficiently generalizable; well-designed observational studies have been suggested as an alternative. We hypothesized that treatment effects of observational studies in cervical disc arthroplasty are similar to those of RCTs. METHODS: We searched electronic database from 2000 to 2014. The Neck Disability Index (NDI) was the primary outcome from which the standardized pre-and-post mean difference (Hedges's g) was determined. Meta-analysis was performed to compare Hedges's g from observational studies to that of RCTs. Potential moderator variables including study quality, age, gender, industry sponsorship, location by continent, and disc types were also collected and analyzed. Observational studies were further stratified into prospective and retrospective, and they were compared to each other as well as to RCTs. RESULTS: We identified nine RCTs, 28 observational studies, and one hybrid study for meta-analysis. NDI Hedges's g was 2.15 for RCTs and 2.03 for observational studies, which was not significant (P = 0.416). No significant difference was found in secondary outcomes. However, after further stratification, prospective observational studies had less treatment effect in Visual Analog Scale neck compared with that of RCTs (1.60 vs. 2.11, P = 0.006). RCTs recruited younger patients (44.1 vs. 45.6, P = 0.008) with worse NDI at baseline (54.30 vs. 46.92, P < 0.001). Patients treated with ProDisc-C showed less standardized improvement on the NDI compared with the patients treated with Prestige (1.41 vs. 2.48, P = 0.026). CONCLUSION: Prospective observational studies that utilize the same features of RCTs such as inclusion and exclusion criteria validated clinical outcomes, and statistical methods can provide valuable information about the treatment effects on a generalizable population. LEVEL OF EVIDENCE: 4.

Site-selective spectroscopy of the solid-state defect chemistry in erbium-doped barium titanate.

Erbium-doped barium titanate crystals were studied by laser-induced fluorescence spectroscopy. Thirteen spectroscopically distinct erbium ion sites were found. The relative concentrations of the different sites changed as a function of the crystal and its preparation and treatment. One major site was present in all crystals. The site distribution was changed either by growing codoped crystals with donor (La3+) and acceptor (Sc3+) ions or by changing the temperature and partial pressure of the oxygen in the annealing atmosphere. Equilibrium calculations were done to simulate the defect distributions that result from the charge compensation of the erbium ions. Comparison with the observed dependence of the site spectral intensities indicated that the erbium enters the lattice on barium sites. We assigned the dominant site to an erbium ion on a barium site that is locally compensated by a barium vacancy, whereas the other lower-intensity sites corresponded to erbium ions that are locally compensated by an electron and a more complex center of an erbium, a barium vacancy, and a hole. The spectra of one sample showed that its defects were different and were characteristic of a sample that had not equilibrated. The new sites in this sample were assigned to erbium entering the lattice on a titanium site, which was then locally compensated by an oxygen vacancy or a hole. Heating equilibrated the sample and changed the erbium to a barium site.

Use of gelatin matrix thrombin tissue sealant as an effective hemostatic agent during laparoscopic partial nephrectomy.

PURPOSE: We describe a technique for achieving effective hemostasis during laparoscopic partial nephrectomy using gelatin matrix thrombin tissue sealant. MATERIALS AND METHODS: Between June 2002 and April 2003, 6 patients underwent laparoscopic partial nephrectomy using the 2-component tissue sealant. Median patient age was 59 years (range 28 to 71) and followup time ranged from 1 to 10 months (median 4.3). The tumor was at least 50% exophytic on preoperative computerized tomography and the diameter ranged from 2 to 3 cm (median 2.5). The 2-component tissue sealant, consisting of a gelatin matrix granula component and a thrombin component, was applied after resection of the tumor and before reperfusion of the kidney. Time until complete hemostasis was achieved, postoperative bleeding, estimated blood loss, warm ischemia time and length of surgery were recorded. RESULTS: Hemostasis was immediate in all cases after application of the tissue sealant for 1 to 2 minutes to the moist resection site. The laparoscopic applicator was used to apply the material to the renal parenchyma. Hemostasis was maintained when reperfusion of the kidney was established. Estimated blood loss ranged from 50 to 350 cc (median 200), and no patient required blood transfusion. Length of surgery ranged from 89 to 230 minutes (median 189), and warm ischemia time ranged from 10 to 14 minutes (median 13). No postoperative bleeding occurred. CONCLUSIONS: The 2-component tissue sealant provided immediate and durable hemostasis in laparoscopic partial nephrectomy. It is a safe and time sparing alternative adjunct to currently available means of achieving hemostasis. In a select patient population use of this agent may reduce warm ischemia time by circumventing the need to perform laparoscopic suturing.

Characterization of prostate cancer missed by sextant biopsy.

There is a trend to increase the number of prostate biopsies taken to increase the detection rate of prostate cancer. We examined radical prostatectomy specimens and correlated the findings to those of preoperative sextant biopsy in an effort to identify the characteristics of tumors that went undetected by our biopsy regimen. Seventy-one patients diagnosed with prostate cancer based on sextant biopsy who underwent radical prostatectomy at our institution from June 1995 to November 2001 had prostatectomy specimens and biopsy slides reviewed. These specimens were step-sectioned and whole-mounted. The location, size, and grade of individual cancer foci in the prostatectomy specimens were correlated with results of the original sextant biopsies. Clinically significant tumors were defined as those with volume > 0.5 mL or Gleason score > or= 7 and extracapsular extension. In 33 patients (46%), there was concordance of biopsy and prostatectomy findings. In 38 patients (54%), additional lesions were demonstrated in the prostatectomy specimens that were not detected by our sextant biopsies. These included 13 cases (34%) with tumors > 0.5 mL and 25 cases in which the lesions were < 0.5 mL in size. However, 7 of these cases contained tumors with Gleason score > or =7. Tumors were located in the transition zone in 8 of these 38 cases (21%), and the remaining tumors were located in the peripheral zone (79%). No tumors with extracapsular extension were missed. Thus, 20 of the 71 cases (28%) had clinically significant cancers that went undetected by the traditional sextant biopsy method. Greater than 50% of patients who underwent sextant biopsy of the prostate had additional tumors that were missed when compared to the pathologic specimen. As many as 28% of these patients had clinically significant cancer based on size and grade criteria. A strategy of increased numbers of biopsies would improve the detection rate of these clinically important tumors. However, the ideal strategy for optimizing cancer detection requires further investigation because increased numbers of biopsies would also increase detection of clinically insignificant tumors.