Functional and structural changes in intestinal smooth muscle after jejunoileal bypass in rats

Active stress and cross-sectional area of intestinal muscle were assessed in tissues taken from unoperated rats, from rats that had undergone bypass of 70% of the small bowel, and from rats that had undergone transection and anastomosis of the bowel. Thirty-five days after operation, muscle from the intestine of transected and bypassed animals elicited active stresses that were equal to or greater than those developed by muscle taken from unoperated animals. The total cross-sectional areas of the in-continuity segment and the area and thickness of the muscle layers of both the in-continuity and bypassed segments were greater when compared with unoperated animals. Significant differences also existed among tissues taken from bypassed and transected animals. Additionally, transection induced increases in active stress, area of muscle in the distal intestine, and circular muscle thickness in the mid- and distal intestine when compared with tissues from unoperated animals. These findings support the hypothesis that intestinal bypass induces increases in functioning smooth muscle tissue.     

Factors leading to local recurrence or death after surgical resection of phyllodes tumours of the breast

BACKGROUND: Local recurrence and death from metastases are occasional, but consistent, themes in reports of patients with phyllodes tumours. Factors that might contribute to these outcomes were sought. METHODS: Data from 38 patients with a phyllodes breast tumour were reviewed retrospectively, reclassifying the pathological material using the Pietruszka and Barnes criteria. RESULTS: At a median of 12 months, nine patients had developed a local recurrence and four had died from metastases. Following local excision in 24 patients (for diagnosis in 13, for 'fibroadenoma' in nine and for phyllodes tumour in two patients), 13 had no further surgery and five had local recurrence (three of eight benign tumours, two of two malignant tumours). Wide local excision or mastectomy in 18 patients was followed by four recurrences (one of eight borderline tumours, three of ten malignant tumours). All patients with recurrence had margin involvement on histological examination, but not all patients with margin involvement developed recurrence. Lack of statistical correlation between local recurrence and age, delay, size, grade or type of surgery was confounded by selection bias for more extensive surgery for malignant tumours. Death correlated with size (P = 0.05) and grade (P = 0.03) of tumour. CONCLUSION: Inadequate preoperative diagnosis ('fibroadenoma' or failure of triple assessment) frequently led to local excision with positive margins. Without revision this often resulted in local recurrence. Local recurrence of any grade was usually followed by further recurrence. Death was related to tumour size and histological grade, confirming these as prognostic factors.     

Postoperative apnea, respiratory strategies, and pathogenesis mechanisms: a review

Recovery from anesthesia is ideally routine and uneventful. After extubation, the recovering postoperative patient ought to breathe without supportive care or additional oxygenation. It has been demonstrated in previous studies that postoperative pulmonary complications are clinically relevant in terms of mortality, morbidity, and length of hospital stay. Compromised postoperative ventilation can be described as the condition in which the postoperative patient does not have satisfactory spontaneous ventilation support and adequate oxygenation. Causes of impaired ventilation, oxygenation, and airway maintenance can be mechanical, hemodynamic, and pharmacologic. This review describes prevalence and differential diagnosis, including co-morbidities of postoperative apnea. The physiological mechanisms of breathing and prolonged postoperative apnea are also reviewed; these mechanisms include influences from the brainstem, the cerebral cortex, and chemoreceptors in the carotid and aortic body. Causes of prolonged postoperative apnea and management are also discussed.     

前列腺癌近距离放疗41例疗效回顾

目的 :观察早期局限性前列腺癌12 5I近距离放疗的临床效果。　方法 :对 4 1例确诊的局限性前列腺癌患者进行前列腺内12 5I植入。采用两步法 ,即治疗前进行前列腺体积研究 ,确定前列腺各部位放射量 ,处方剂量 16 0Gy;治疗中直肠超声波探头和C臂X线协助定位 ,专职护士长期随访。　结果 :获得长期随访 (3～ 4年 ) 33例(80 % ) ,其中 2例 (6 % )前列腺特异抗原 (PSA)升高者经穿刺确诊肿瘤局部复发 ,无死亡病例。早期并发症主要为尿路刺激症状 ,6个月内症状严重 ,1年以后症状消失。　结论 :前列腺近距离放疗生存率高 ,有短期尿路刺激症状 ,长期并发症少。     

Breast Surgery Outcomes as Quality Measures According to the NSQIP Database

Background

The National Surgical Quality Improvement Program (NSQIP) is a risk-adjusted database designed to benchmark quality initiatives. NSQIP captures uniform morbidity variables for all operations and calculates expected morbidity probabilities. Given the frequent need for reoperation following breast-conserving surgery (BCS) and mastectomy, we hypothesized that NSQIP may inaccurately reflect surgical morbidity after breast cancer operations.

Methods

Using the 2008 NSQIP database, we identified 24,447 breast surgery patients. We calculated the observed versus expected (O/E) morbidity ratios, compared them to other general surgery procedures, and analyzed the O/E morbidity ratios among benign and malignant breast diagnoses.

Results

The NSQIP database shows that breast surgery has an O/E morbidity ratio of 3.11, which is higher than other general surgery procedures. Additionally, breast operations for malignancy have higher O/E morbidity ratios (3.22) than those performed for benign disease (2.59). Analysis of malignant patients by CPT code revealed that BCS patients had an O/E morbidity ratio of 7.75 and attributed 89?% of morbidity to reoperation, whereas mastectomy patients had an O/E morbidity ratio of only 1.7. Elimination of the reoperation variable from morbidity calculations in breast surgery reduces the O/E morbidity ratio to less than expected in all breast procedures.

Discussion

Breast surgery has a higher O/E morbidity ratio than other general surgery procedures. Reoperations are expected in BCS for positive margins and in mastectomy for completion ALND. Breast surgeons should advocate for benchmarking by surgical site-specific metrics, because current NSQIP criteria may negatively affect the quality assessment of high-volume breast centers.     

Applicability of apparent diffusion coefficient ratios in preoperative diagnosis of common pediatric cerebellar tumors across two institutions

Introduction

The purpose of our study was to test the accuracy and applicability of decision rules utilizing apparent diffusion coefficient (ADC) ratios on accurate preoperative diagnosis of common pediatric cerebellar tumors across two institutions.

Methods

In this HIPAA-compliant, IRB-approved study, performed at two institutions, 140 pediatric cerebellar tumors were included. Two separate reviewers placed regions of interest on the solid components of 140 tumors (98 at site A and 42 at site B) and normal brain on the ADC maps. The third reviewer who was blinded to the histopathological diagnoses made the same measurements on 140 patients to validate the data. Tumor to normal brain ADC ratios were calculated. Receiver operator curve (ROC) analysis was performed to generate thresholds to discriminate tumors. Utility of decision rules based on these thresholds was tested.

Results

While ADC values of medulloblastomas were different between the sites, there was no difference among the ADC ratios of medulloblastomas, pilocytic astrocytomas, ependymomas, and atypical teratoid rhabdoid tumors between the sites. ADC ratio of ≥1.8 correctly discriminated pilocytic astrocytomas from ependymomas with a sensitivity of 0.83 and a specificity of 0.78. ADC ratio of <1.2 correctly discriminated ependymomas from embryonal tumors with a sensitivity of 0.87 and a specificity of 0.83. The proposed decision rules correctly discriminated 120 of the 140 tumors (85.71 %). Age ≥2 years criterion correctly sorted medulloblastomas in 84.48 % of patients and age <2 years correctly distinguished atypical teratoid rhabdoid tumors in 90.00 % of patients with embryonal tumors.

Conclusions

Decision rules based on ADC ratios are applicable across two institutions in the accurate preoperative diagnosis of common pediatric cerebellar tumors.     

How long should you wait for a chest radiograph after placing a chest tube on water seal? A prospective study

OBJECTIVE: The purpose of this study was to determine the optimal time interval for identifying a pneumothorax (PTX) on chest radiograph (CXR) after placing a chest tube on water seal. METHODS: One hundred nineteen chest tubes were placed on water seal according to a prospective, observational study protocol. After water seal, both an early (3.1 +/- 2.1 hours) and a late (17.6 +/- 8.0 hours) CXR was obtained. RESULTS: Thirty-one patients had a PTX on follow-up CXRs. There were 22 early and 9 late PTXs identified. Three patients in the early group had a clinically significant PTX or an increase in the size of PTX on follow-up CXR. None of the patients in the late group had a clinically significant PTX (any worsening of their PTX) or required further intervention. CONCLUSION: A normal chest radiograph obtained 3 hours after placing a chest tube on water seal effectively excludes development of a clinically significant pneumothorax.