Assessment of intraoperative microaspiration: does a modified cuff shape improve sealing?

BACKGROUND: Intra-operative aspiration of oropharyngeal secretions is associated with post-operative pneumonia. The use of endotracheal tubes (ETTs) with a modified cuff shape could be one preventive action. In this clinical, prospective, randomised controlled trial, we hypothesised that altering the cuff shape to a tapered shape could reduce the aspiration incidence. The primary outcome was aspiration of dye solution into the trachea. METHODS: Patients scheduled for lumbar surgery were intubated with either an ETT with a barrel-shaped polyvinylchloride cuff (control group, n = 30) or tapered-shaped polyvinylchloride cuff (intervention group, n = 30). Subsequently, instillation with methylthioninium chloride was performed. At 10, 30, 60, 90, and 120 min after intubation, bronchoscopy was performed assessing the degree of dye descent along the cuff and digitally stored. Single blind review of the videoclips provided data on incidence of dye aspiration and depth of penetration along the cuff. RESULTS: The traditional cuff showed descent of dye into the trachea in 20% of the patients. Although a tapered-shaped polyvinylchloride cuff leaked up to the second third of the cuff, no dye leakage into the trachea was observed. The use of a tapered-shaped cuff had a protective role against aspiration (T30: OR 3.0, CI 1.57-5.75; P = 0.001). CONCLUSIONS: Short-term use of tapered-shaped polyvinylchloride cuffs in surgical patients results in more effective sealing of the tracheal lumen in comparison with a traditional barrel-shaped polyvinylchloride cuffs. Further evaluation is needed to determine whether a reduction in post-operative pneumonia can be demonstrated when these cuffs are used.

Tapering with Pharmaceutical GHB or Benzodiazepines for Detoxification in GHB-Dependent Patients: A Matched-Subject Observational Study of Treatment-as-Usual in Belgium and The Netherlands.

BACKGROUND: The gamma-hydroxybutyric acid (GHB) withdrawal syndrome often has a fulminant course, with a rapid onset and swift progression of severe complications. In clinical practice, two pharmacological regimens are commonly used to counteract withdrawal symptoms during GHB detoxification: tapering with benzodiazepines (BZDs) or tapering with pharmaceutical GHB. In Belgium, standard treatment is tapering with BZDs, while in the Netherlands, pharmaceutical GHB is the preferred treatment method. Though BZDs are cheaper and readily available, case studies suggest GHB tapering results in less severe withdrawal and fewer complications. OBJECTIVES: This study aimed to compare two treatments-as-usual in tapering methods on withdrawal, craving and adverse events during detoxification in GHB-dependent patients. METHODS: In this multicentre non-randomised indirect comparison of two treatments-as-usual, patients with GHB dependence received BZD tapering (Belgian sample: n = 42) or GHB tapering (Dutch sample: n = 42, matched historical sample). Withdrawal was assessed using the Subjective and Objective Withdrawal Scales, craving was assessed with a Visual Analogue Scale and adverse events were systematically recorded. Differences in withdrawal and craving were analysed using a linear mixed-model analysis, with 'days in admission' and 'detoxification method' as fixed factors. Differences in adverse events were analysed using a Chi-square analysis. RESULTS: Withdrawal decreased over time in both groups. Withdrawal severity was higher in patients receiving BZD tapering (subjective mean = 36.50, standard deviation = 21.08; objective mean = 8.05, standard deviation = 4.68) than in patients receiving pharmaceutical GHB tapering (subjective mean = 15.90; standard deviation = 13.83; objective mean = 3.72; standard deviation = 2.56). No differences in craving were found. Adverse events were more common in the BZD than the GHB group, especially delirium (20 vs 2.5%, respectively). CONCLUSIONS: These results support earlier work that BZD tapering might not always sufficiently dampen withdrawal in GHB-dependent patients. However, it needs to be taken into account that both treatments were assessed in separate countries. Based on the current findings, tapering with pharmaceutical GHB could be considered for patients with GHB dependence during detoxification, as it has potentially less severe withdrawal and fewer complications than BZD tapering.

Diffusion-weighted MR imaging of intracerebral masses: comparison with conventional MR imaging and histologic findings.

BACKGROUND AND PURPOSE: The purposes of this study were to find the role of diffusion-weighted MR imaging in characterizing intracerebral masses and to find a correlation, if any, between the different parameters of diffusion-weighted imaging and histologic analysis of tumors. The usefulness of diffusion-weighted imaging and apparent diffusion coefficient (ADC) maps in tumor delineation was evaluated. Contrast with white matter and ADC values for tumor components with available histology were also evaluated. METHODS: Twenty patients with clinical and routine MR imaging/CT evidence of intracerebral neoplasm were examined with routine MR imaging and echo-planar diffusion-weighted imaging. The routine MR imaging included at least the axial T2-weighted fast spin-echo and axial T1-weighted spin-echo sequences before and after contrast enhancement. The diffusion-weighted imaging included an echo-planar spin-echo sequence with three b values (0, 300, and 1200 s/mm(2)), sensitizing gradient in the z direction, and calculated ADC maps. The visual comparison of routine MR images with diffusion-weighted images for tumor delineation was performed as was the statistical analysis of quantitative diffusion-weighted imaging parameters with histologic evaluation. RESULTS: For tumors, the diffusion-weighted images and ADC maps of gliomas were less useful than the T2-weighted spin-echo and contrast-enhanced T1-weighted spin-echo images in definition of tumor boundaries. Additionally, in six cases of gliomas, neither T2-weighted spin-echo nor diffusion-weighted images were able to show a boundary between tumor and edema, which was present on contrast-enhanced T1-weighted and/or perfusion echo-planar images. The ADC values of solid gliomas, metastases, and meningioma were in the same range. In two cases of lymphomas, there was a good contrast with white matter, with strongly reduced ADC values. For infection, the highest contrast on diffusion-weighted images and lowest ADC values were observed in association with inflammatory granuloma and abscess. CONCLUSION: Contrary to the findings of previous studies, we found no clear advantage of diffusion-weighted echo-planar imaging in the evaluation of tumor extension. The contrast between gliomas, metastases, meningioma, and white matter was generally lower on diffusion-weighted images and ADC maps compared with conventional MR imaging. Unlike gliomas, the two cases of lymphomas showed hyperintense signal on diffusion-weighted images whereas the case of cerebral abscess showed the highest contrast on diffusion-weighted images with very low ADC values. Further study is required to find out whether this may be useful in the differentiation of gliomas and metastasis from lymphoma and abscess.

Cushing's disease: diagnosis through the nose. A case report.

In Cushing's disease clinical symptoms are usually related to the ACTH hypersecretion. On diagnosis these secreting tumours tend to be small due to their ability to reach clinical detection early. However, symptoms may also be caused by mass-related effects such as the depression of secretion of other pituitary hormones. Furthermore growth related symptoms may occur due to the invasion of the suprasellar region with compression of the visual system. As we illustrate in a case report, when spreading of pituitary adenoma occurs to the infrasellar region, Cushing disease may manifest itself by rather atypical initial symptoms that are more related to ear-nose-throat (ENT) complaints. In these invasive macro adenomas multimodal therapy is usually required to achieve control of hypersecretion and mass related symptoms.

Bradykinin analogs containing the 4-amino-2-benzazepin-3-one scaffold at the C-terminus.

High affinity peptide ligands for the bradykinin (BK) B(2) subtype receptor have been shown to adopt a beta-turn conformation of the C-terminal tetrapeptide (H-Arg(1)-Pro(2)-Pro(3)-Gly(4)-Phe(5)-Ser(6)-Pro(7)-Phe(8)-Arg(9)-OH). We investigated the replacement of the Pro(7)-Phe(8) dipeptide moiety in BK or the D-Tic(7)-Oic(8) subunit in HOE140 (H-D-Arg(0)-Arg(1)-Pro(2)-Hyp(3)-Gly(4)-Thi(5)-Ser(6)-D-Tic(7)-Oic(8)-Arg(9)-OH) by 4-amino-1,2,4,5-tetrahydro-2-benzazepin-3-one templates (Aba). Binding studies to the human B(2) receptor showed a correlation between the affinities of the BK analogs and the propensity of the templates to adopt a beta-turn conformation. The L-spiro-Aba-Gly containing HOE140 analog BK10 has the best affinity, which correlates with the known turn-inducing property of this template. All the compounds did not modify basal inositolphosphate (IP) output in B(2)-expressing CHO cells up to 10 microM concentration. The antagonist properties were confirmed by the guinea pig ileum smooth muscle contractility assay. The new amino-benzazepinone (Aba) substituted BK analogs were found to be surmountable antagonists.

Prognostic value of perfusion-weighted imaging in brain glioma: a prospective study.

OBJECT: Biopsy targeting based on MR imaging alone may fail to identify malignant areas in brain gliomas. Considering the differences in relative Cerebral Blood Volume (rCBV) ratios reported among tumour grades, we evaluated whether perfusion-weighted MR imaging (PWI) could usefully implement the routine preoperative imaging by detecting those areas bearing a higher yield for malignancy to guide the stereotactic biopsy or the surgical removal. CLINICAL MATERIAL AND METHODS: We studied a series of 55 consecutive patients with newly diagnosed brain glioma using both conventional MR imaging and PWI in the preoperative assessment. The pathological diagnosis was established by stereotactic biopsy in 29 cases and by craniotomy in 24 cases. We evaluated the patient survival to detect undergrading. DISCUSSION: Independent from contrast-enhancement, perfusion-weighted MR imaging improved the target selection in stereotactic biopsy guidance and the removal of malignant areas in tumours amenable to surgery. Particularly sensitive to the perfused part of the tumour as to small regional changes, rCBV maps allowed a better detection of malignant areas. The rCBV ratios correlated significantly to the tumour grade and the final outcome (p < 0.01). CONCLUSIONS: We found PWI valuable in the preoperative assessment of brain gliomas, discriminating high from low-grade gliomas. PWI can easily be performed on widely available MR imaging systems as part of the routine imaging of gliomas.