The comparison of two negative‐pressure wound therapy systems in a porcine model of wound healing

The purpose of this study was to compare two negative‐pressure wound healing systems (NPWT), ?75 mmHg with a silicone‐coated (SC) dressing and ?125 mmHg with polyurethane foam dressing (standard of care). In addition, this study compared the effects of two different dressing interfaces, SC dressing and gauze, with ?75 mmHg pressure. For both comparisons, two groups of five pigs were evaluated over a 21‐day time course. Two excisional wounds were made on each animal and NPWT dressings were applied. A canvas saddle was constructed to hold the NPWT device so the animal had free range of the pen. Dressings were changed twice a week and wound measurements were taken. Specimens for histology and gene expression analyses were taken on day 7 and 21. These data show that there is increased expression in a few genes associated with remodeling and inflammatory processes in the NPWT‐125 with polyurethane foam as compared with the NPWT‐75 with SC dressing. These two systems, however, are equivalent with respect to wound healing, histology, and gene expression over 21 days of healing. Further, we demonstrate that there is no difference in measure of healing between the SC dressing and a basic gauze dressing.     

Short-Term Outcomes after Combined Colon and Liver Resection for Synchronous Colon Cancer Liver Metastases: A Population Study

Introduction

The timing of surgical resection for stage IV colon cancer with liver metastasis and the safety of simultaneous colon and liver resection remains controversial. The purpose of our study was to evaluate short-term outcomes after combined colon and liver resection (CCLR) versus colon resection (CR) or liver resection alone (LR) using a population database.

Methods

The National Inpatient Sample was used to select patients who had surgery for colon cancer from 2002 to 2006. We evaluated for in-hospital morbidity, mortality, and prolonged length of stay (PLOS). Our analysis was done using design-weighted unadjusted analysis and logistic regression.

Results

We identified 361,096 patients during our study period (CCLR 3,625; CR 322,286; LR 35,185). CCLR was not associated with an increased risk of complications (odds ratio (OR) 1.12; 95 % confidence interval (CI) 0.94–1.33; P = 0.21) or PLOS (OR 1.19; 95 % CI 0.99–1.4; P = 0.06) compared with CR. In-hospital mortality occurred in 3.5 % of patients who underwent CCLR and was not significantly associated with mortality compared with CR alone (OR 1.17; 95 % CI 0.79–1.74; P = 0.43). Liver lobectomy with CR was associated with a PLOS and a trend toward increased morbidity and mortality. Significant predictors of complications, mortality, and PLOS included: age >70 years, male gender, nonprivate health insurance, and Elixhauser score >1.

Conclusions

CCLR with limited liver resection can be performed with similar morbidity and mortality to colectomy alone. For patients who require hepatic lobectomy, however, strong consideration should be given to a staged approach.     

Quantitative X-ray Computed Tomography Peritoneography in Malignant Peritoneal Mesothelioma Patients Receiving Intraperitoneal Chemotherapy

Background

Intraperitoneal chemotherapy is used to treat peritoneal surface-spreading malignancies. We sought to determine whether volume and surface area of the intraperitoneal chemotherapy compartments are associated with overall survival and posttreatment glomerular filtration rate (GFR) in malignant peritoneal mesothelioma (MPM) patients.

Methods

Thirty-eight MPM patients underwent X-ray computed tomography peritoneograms during outpatient intraperitoneal chemotherapy. We calculated volume and surface area of contrast-filled compartments by semiautomated computer algorithm. We tested whether these were associated with overall survival and posttreatment GFR.

Results

Decreased likelihood of mortality was associated with larger surface areas (p = 0.0201) and smaller contrast-filled compartment volumes (p = 0.0341), controlling for age, sex, histologic subtype, and presence of residual disease >0.5 cm postoperatively. Larger volumes were associated with higher posttreatment GFR, controlling for pretreatment GFR, body surface area, surface area, and the interaction between body surface area and volume (p = 0.0167).

Discussion

Computed tomography peritoneography is an appropriate modality to assess for maldistribution of intraperitoneal chemotherapy. In addition to identifying catheter failure and frank loculation, quantitative analysis of the contrast-filled compartment’s surface area and volume may predict overall survival and cisplatin-induced nephrotoxicity. Prospective studies should be undertaken to confirm and extend these findings to other diseases, including advanced ovarian carcinoma.

     

Apolipoprotein E s4 Allele and Outcomes of Traumatic Spinal Cord Injury

Abstract

Background/Objective: To test the hypothesis that apolipoprotein E (APOE) polymorphisms are associated with outcomes after spinal cord injury (SCI).

Methods: Retrospective cohort study, from rehabilitation admission to discharge.

Participants: Convenience sample of 89 persons with cervical SCI (C3-C8) treated from 1995 through 2003. Median age was 30 years (range 14-70); 67 were male (75%) and 83 were white (93%).

Main Outcome Measures: American Spinal Injury Association (ASIA) motor and sensory scores, ASIA Impairment Scale (AIS), time from injury to rehabilitation admission, and length of stay (LOS) in rehabilitation.

Results: Subjects with an APOE s4 allele (n = 15; 17%) had significantly less motor recovery during rehabilitation than did individuals without an s4 allele (median 3.0 vs 5.5; P < 0.05) and a longer rehabilitation LOS (median 106 vs 89 days; P = 0.04), but better sensory-pinprick recovery (median 5.0 vs 2.0; P = 0.03). There were no significant differences by APOE s4 allele status in sensory-light touch recovery, likelihood of improving AIS Grade, or time from injury to rehabilitation admission.

Conclusions: APOE ε4 allele was associated with differences in neurological recovery and longer rehabilitation LOS. Genetic factors may be among the determinants of outcome after SCI and warrant further study.     

Rectal Cancer and Teaching Hospitals: Hospital Teaching Status Affects Use of Neoadjuvant Radiation and Survival for Rectal Cancer Patients

Background

For rectal cancer, it is unknown how use of radiation, treatment cost, and survival differ based on hospital teaching designation.

Methods

Private insurance claims data linked with the Pennsylvania Cancer Registry were used to identify rectal cancer patients undergoing surgery from 2004 to 2006. Patients with missing data of interest were excluded. Hospitals were characterized as follows: large (≥200 beds) versus small size (<200 beds), teaching versus nonteaching, and urban versus rural. Logistic regression was used to model the use of neoadjuvant radiotherapy, and Cox proportional hazards models were used to compare cancer-specific survival between hospital types.

Results

A total of 432 patients were analyzed. There was no difference in the distribution of cancer stages among the various hospital types (all p > 0.20). Teaching hospitals were associated with significantly higher utilization of neoadjuvant radiotherapy for stage II and III cancers compared with nonteaching facilities (57 vs. 28 %; p < 0.0001). On multivariate analysis, teaching status was the only hospital designation associated with use of neoadjuvant radiation (p < 0.001); hospital size and rural/urban designation were not significant. Nonteaching hospitals were more likely to use adjuvant radiotherapy for stage II and III disease (13 vs. 30 %; p < 0.01). Teaching hospitals had lower odds of death from rectal cancer when evaluating all stages [hazard ratio (HR) = 0.35; p < 0.0001] with similar costs of inpatient treatment (teaching: US $30,769 versus nonteaching: US $26,892; p = 0.22).

Conclusions

Teaching designation was associated with higher incidence of neoadjuvant radiotherapy for stage II and III disease, with improved cancer-specific survival compared with nonteaching hospitals, and with similar treatment costs.     

Double dissociation of letter and category fluency following left frontal and temporal lobe lesions

Background: A number of studies have suggested that temporal cortex is critical for the ability to generate exemplars belonging to a particular semantic category (i.e., category fluency), while frontal cortex is critical for generating words beginning with a particular letter (i.e., letter or phonemic fluency). However, previous studies have often focused on relative, quantitative differences in performance across groups of patients and primarily in the oral domain.

Aims: The current study analysed verbal fluency data from two individuals with chronic aphasia, one with a large left temporal lobe lesion and a severe Wernicke's aphasia, and a second individual with a large left frontal lobe lesion and a moderately severe non-fluent aphasia. The goal of the study was to do both qualitative and quantitative analyses of letter and category fluency performance in these two individuals across oral and written fluency domains.

Methods & Procedures: Participants were administered both oral and written versions of letter fluency (FAS) and category fluency conditions (fruits, animals, and supermarket items). Participants were given 90 seconds to generate as many items as possible, and their responses were scored for both overall output, as well as qualitative structure using a clustering analysis.

Outcomes & Results: The individual with an extensive temporal lobe lesion generated a large number of exemplars on the letter fluency task. Some of these items were neologisms (e.g., frest, anth, and swink), but remarkably all adhered to the phonological constraints of the task. However, this individual was very poor at generating items belonging to semantic categories. In contrast, the individual with a large frontal lesion generated many exemplars on the category fluency task but only two items on the letter fluency task. The same pattern was replicated in the written domain in both individuals, and results from the clustering analysis paralleled these quantitative findings.

Conclusions: This report describes two individuals with aphasia who exhibited a double dissociation between letter and category fluency performance in both oral and written domains. The current findings provide further evidence for the notion that left frontal cortex is critical for word retrieval based on phonology, while left temporal cortex is critical for word retrieval based on semantics. The findings have implications for the types of strategies that may be most effective in individuals with lesions to these brain regions critical for word retrieval.