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91.
Controversy exists concerning the degree of microbial contamination associated with the us of rigid lumened medical devices, the efficacy of standard cleaning techniques used to remove pathogenic microorganisms from lumen channels, and whether patients are placed at risk of cross infection because of microbial contamination. In this study the level and types of microorganisms found on rigid lumened medical devices before and after cleaning in a hospital environment were investigated. The bioburden level after clinical use was found to be relatively low, ranging from 101 to 104 colony forming units (CFU) per device. After the instruments were cleaned, none of the devices studied contained bioburden levels greater than 104 CFU and 83% had bioburden levels less than or equal to 102 CFU. The bioburden present before cleaning was comprised of organisms derived from the handling of the device, from the hospital environment, and from the patient. The bioburden present after cleaning was comprised of organisms typically derived from the handling of the device and from the hospital environment. The level of bioburden per device was also related to the anatomic site where the device was used, with lower numbers of organisms found on devices exposed to sterile body sites and the respiratory tract.  相似文献   
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Purpose

The aim of this study was to evaluate the utility of added DWI sequences as an adjunct to traditional MR imaging in the evaluation of abnormal placentation in patients with suspicion for placenta accreta spectrum abnormality or morbidly adherent placenta (MAP).

Materials and methods

The study was approved by local ethics committee. The subjects included pregnant women with prenatal MRI performed between July 2013 to July 2015. All imaging was performed on a Philips 1.5T MR scanner using pelvic phased-array coil. Only T2-weighted and diffusion-weighted imaging (DWI) series were compiled for review. Two randomized imaging sets were created: set 1 included T2-weighted series only (T2W); set 2 included T2W with DWI series together (T2W + DWI). Three radiologists, blinded to history and pathology, reviewed the imaging, with 2 weeks of time between the two image sets. Sensitivity, specificity, and overall accuracy for MAP were calculated and compared between T2W only and T2W + DWI reads. Associations between imaging findings and invasion on pathology were tested using the Chi-squared test. Confidence scores, inter-reader agreement, and systematic differences were documented.

Results

A total of 17 pregnant women were included in the study. 8 cases were pathologically diagnosed with MAP. There were no significant differences in the diagnostic accuracy between T2W and T2W + DWI in the diagnosis of MAP in terms of overall accuracy (62.7% for T2W vs. 68.6% for T2W + DWI, p = 0.68), sensitivity (70.8% for T2W vs. 95.8% for T2W + DWI, p = 0.12), and specificity (55.6% for T2W vs. 44.4% for T2W + DWI, p = 0.49). There was no significant difference in the diagnostic confidence between the review of T2W images alone and the T2W + DWI review (mean 7.3 ± 1.8 for T2W vs. 7.5 ± 1.8 for T2W + DWI, p = 0.37).

Conclusion

With the current imaging technique, addition of DWI sequence to the traditional T2W images cannot be shown to significantly increase the accuracy or reader confidence for diagnosis of placenta accreta spectrum abnormality. However, DWI does improve identification of abnormalities in the placental–myometrial interface.

  相似文献   
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With the expansion of newborn screening to include many organic acidurias and fatty acid oxidation defects, effective therapies of these disorders will be needed. Currently severe disorders such as methylmalonic and propionic aciduria. conventional therapy with diet and oral L-camitine often prove ineffective in preventing failure to thrive and recurrent metabolic decompensations. L-carnitine provides a natural pathway for removal of the toxic metabolites in these disorders and is life saving therapy but, with poor oral absorption (25%), it is difficult to supply adequate carnitine to meet the metabolic needs of these patients. Long term intravenous L-carnitine therapy, administered through a subcutaneous venous access port in 5 patients with organic acidurias [propionic aciduria (2), methylmalonic aciduria (2), 3 methylglutaconic aciduria(1)] resulted in improved growth, lower frequency of metabolic decompensations and increased tolerance of natural protein in the diet. An added benefit was the ability to initiate fluid. electrolytes, and antibiotics during metabolic decompensations at home thus averting hospitalizations.  相似文献   
97.
Myocardial contrast echocardiography using power modulation real-time perfusion (RTP) is an appealing method for bedside risk stratification of patients with acute coronary syndrome. In this study, we aimed to evaluate the accuracy in predicting significant coronary stenosis of a bedside RTP adenosine stress protocol in patients with acute coronary syndrome. METHODS: Prior to coronary angiography, 36 consecutive in-patients with acute coronary syndrome underwent a bedside adenosine stress echocardiography with RTP in the coronary care unit. Visual assessment of both perfusion and wall motion was made, comparing rest and hyperaemia images. Each segment was attributed to one of the three main coronary vessel areas. RESULTS: The sensitivity of predicting significant stenosis was 87, 83 and 81% for left anterior descending, circumflex and right posterior descending areas, respectively. Specificity was 69, 67 and 60%, respectively. The positive predictive values were 83, 79 and 74%, respectively. CONCLUSIONS: RTP using adenosine is a feasible bedside tool in predicting the area of significant coronary stenosis and could be helpful as a bedside decision-making tool in the clinical setting. More studies are required to assess the clinical value of RTP adenosine stress echocardiography.  相似文献   
98.
AIMS: Data on the diagnostic accuracy of neuron-specific enolase (NSE) as marker of hypoxic brain damage are conflicting. The purpose of this prospective observational cohort study was to explore the prognostic value of serum NSE after cardiopulmonary resuscitation (CPR) and to define the most sensitive cutoff value with a specificity of 100% for the prediction of persistent coma. METHODS AND RESULTS: Serum NSE concentrations were serially determined in 227 consecutive unconscious patients after CPR who were classified according to the best Glasgow-Pittsburgh cerebral performance categories (CPC, 1-4) achieved within 6 months follow-up. Sixteen patients were excluded due to incomplete NSE data and 34 due to death under analgesia sedation. The prevalence of poor neurological outcome (persistent coma, CPC 4) in our 177 analysed patients was 33%. At a specificity of 100%, a peak NSE concentration above 80 ng/mL predicted persistent coma with a sensitivity of 63%, a positive predictive value of 100%, a negative predictive value of 84%, and a predictive accuracy of 88%. CONCLUSION: A peak serum NSE concentration exceeding 80 ng/mL is a highly specific but only moderately sensitive marker for a poor neurological outcome after CPR.  相似文献   
99.

Introduction

Surgical site infection (SSI) is an infection occurring in an incisional wound within 30 days of surgery and significantly affects patients undergoing colorectal surgery. This study examined a multi-institutional dataset to determine risk factors for SSI following colorectal resection.

Methods

Data on 386 patients who underwent colorectal resection in three institutions were accrued. Patients were identified using a prospective SSI database and hospital records. Data are presented as median (interquartile range), and logistic regression analysis was used to identify risk factors.

Results

Patients (21.5 %) developed a postoperative SSI. The median time to the development of SSI was 7 days (5–10). Of all infections, 67.5 % were superficial, 22.9 % were deep and 9.6 % were organ space. In univariate analysis, an ASA grade of II (RR 0.6, CI 0.3–0.9, P?=?0.019), having an elective procedure (RR 0.4, CI 0.2–0.6, P?<?0.001), using a laparoscopic approach (RR 0.5, CI 0.3–0.9, P?=?0.019), having a daytime procedure (RR 0.3, CI 0.1–0.7, P?=?0.006) and having a clean/contaminated wound (RR 0.4, CI 0.2–0.7, P?=?0.001) were associated with reduced risk of SSI. In multivariate analysis, an ASA grade of IV (RR 3.9, CI 1.1–13.7, P?=?0.034), a procedure duration over 3 h (RR 4.3, CI 2.3–8.2, P?<?0.001) and undergoing a panproctocolectomy (RR 6.5, CI 1.0–40.9, P?=?0.044) were independent risk factors for SSI. Those who developed an SSI had a longer duration of inpatient stay (22 days [16–31] vs 15 days [10–26], P?<?0.001).

Conclusions

Patients who develop an SSI have a longer duration of inpatient stay. Independent risk factors for SSI following colorectal resection include being ASA grade IV, having a procedure duration over 3 h, and undergoing a panproctocolectomy.
  相似文献   
100.
Healthy stem cell donors start leukapheresis 4-5 days after starting G-CSF based on the peripheral blood CD34+ cell count (PBCD34). Data from 137 harvests (68 donors) were analyzed to determine correlation between pre-apheresis leukocytes (11.0-94.8x10(9)/l; median 38.8) and platelets (49-374x10(9)/l; median 180), and PBCD34 (3-276/microl; median 40). PBCD34 correlated positively with leukocytes (r=0.48; P<0.0001) and platelets (r=0.40; P<0.0001). When pre-apheresis leukocytes were >or=25 and platelets were >or=100, PBCD34 and CD34+ collection were 5-276/microl (median 57) and 0.5-27.6x10(6)/kg (median 4.7), respectively; significantly higher than PBCD34 of 3-74/microl (median 17) and CD34+ collection of 0.2-8.9 x 10(6)/kg (median 2.2) when leukocytes were <25 and/or platelets were <100. With leukocytes >or=25 and platelets >or=100, PBCD34 was low (<20/microl) 8% of the time, compared to 57% of the time with leukocytes <25 and/or platelets <100 (P<0.0001). Our data suggest that it is not always necessary to measure PBCD34 to guide leukapheresis in healthy donors because pre-apheresis leukocytes and platelets >or=25 and >or=100, respectively, are associated with excellent mobilization. When blood counts do not meet these criteria, PBCD34 should be determined prior to initiation of apheresis.  相似文献   
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