Procalcitonin in the recognition of complications in critically ill surgical patients

Background

Procalcitonin (PCT) is a relatively new, promising indirect parameter for infection. In the intensive care unit (ICU) it can be used as a marker for sepsis. However, in the ICU there is a need for reliable markers for clinical deterioration in the critically ill patients. This study determines the clinical value of PCT concentrations in recognizing surgical complications in a heterogeneous group of general surgical patients in the ICU.

Material and methods

We prospectively collected PCT concentration data from April 2010 to June 2012 for all general surgical patients admitted to the ICU. Both the relationships between PCT levels and events (diagnostic and therapeutic interventions) as well as between PCT levels and surgical complications (abscesses, bleeding, perforation, ischemia, and ileus) were studied.

Results

PCT concentrations were lower in patients who developed complications than those who did not develop complications on the same day, although not significant (P = 0.27). A 10% increase in PCT levels resulted in a 2% higher complication odds, but again this was not significant (odds ratio [OR], 1.020; 95% confidence interval [CI], 0.961–1.083; P = 0.51). Even a 20% or 30% increase in PCT concentrations did not result in higher complication probability (OR, 1.039; 95% CI, 0.927–1.165 and OR, 1.057; 95% CI, 0.897–1.246). Furthermore, an increase in PCT levels did not show an increase or a reduction in the number of diagnostic and therapeutic interventions.

Conclusions

An increase in PCT levels does not help to predict surgical complications in critically ill surgical patients.     

Assessing Internet Addiction Using the Parsimonious Internet Addiction Components Model—A Preliminary Study

Internet usage has grown exponentially over the last decade. Research indicates that excessive Internet use can lead to symptoms associated with addiction. To date, assessment of potential Internet addiction has varied regarding populations studied and instruments used, making reliable prevalence estimations difficult. To overcome the present problems a preliminary study was conducted testing a parsimonious Internet addiction components model based on Griffiths’ addiction components (Journal of Substance Use, 10, 191–197, 2005), including salience, mood modification, tolerance, withdrawal, conflict, and relapse. Two validated measures of Internet addiction were used (Compulsive Internet Use Scale [CIUS], Meerkerk et al. in Cyberpsychology & Behavior, 12(1), 1–6, 2009, and Assessment for Internet and Computer Game Addiction Scale [AICA-S], Wölfling et al. 2010) in two independent samples (ns?=?3,105 and 2,257). The fit of the model was analysed using Confirmatory Factor Analysis. Results indicate that the Internet addiction components model fits the data in both samples well. The two sample/two instrument approach provides converging evidence concerning the degree to which the components model can organize the self-reported behavioural components of Internet addiction. Recommendations for future research include a more detailed assessment of tolerance as addiction component.     

Positive remodeling at 3 year follow up is associated with plaque free coronary wall segment at baseline: A serial IVUS study

Aims

At present it is unknown what limits the arterial remodeling process during atherosclerotic plaque formation. In healthy arteries remodeling is regulated by the shear stress induced response by the endothelium. As endothelium at the plaque site is assumed to be dysfunctional, we tested the hypothesis that plaque free wall (PFW) determines vascular remodeling during atherosclerotic plaque build-up.

Methods & results

66 human coronary ROIs (38 patients) were studied at baseline and at 3 years follow up applying intravascular ultrasound (IVUS). From the IVUS images the lumen and external elastic membrane contours were delineated to assess wall thickness (WT), vessel area (VA), Plaque Area (PA) and plaque burden (PA/VA*100%). WT < 0.5 mm was defined as normal and determined the arc of the PFW (0–360°). Positive remodeling was defined as relative difference of VA over time >5%. At baseline, IVUS-PFW was inversely related to plaque burden (p < 0.05). Positive remodeling was most frequently observed in ROIs with IVUS-PFW > 180° (i.e. larger than half of the circumference) compared to PFW < 180° (55% vs. 12%, p < 0.05). Accordingly, plaques with IVUS-PFW > 180° at baseline had the largest change in VA (1.1 ± 2.1 vs. −0.4 ± 0.6 mm², p < 0.05) with an odds ratio of 9.2 to develop positive remodeling.

Conclusions

Our serial IVUS data show that IVUS-PFW is a determinant of vascular remodeling. ROIs with PFW > 180 at baseline had the highest probability to undergo positive remodeling.     

Parenteral monofluorophosphate (MFP) is a more potent inducer of enamel fluorotic defects in neonatal hamster molars than sodium fluoride

Supra-optimal intake of sodium fluoride (NaF) during early childhood results in formation of irreversible enamel defects. Monofluorophosphate (MFP) was considered as less toxic than NaF but equally cariostatic. We compared the potency of MFP and NaF to induce pre-eruptive sub-ameloblastic cysts and post-eruptive white spots and pits in developing hamster enamel. Hamster pups were injected subcutaneously with either NaF or MFP in equimolar doses of either 9 mg or 18 mg F/kg body weight. At 9 mg F/kg, MFP induced more but smaller sub-ameloblastic cysts with a collective cyst volume twice as large as that induced by NaF. Eight days after F injection, all F-injected groups had formed 4–6 white spots per molar, with an additional 2 pits per molar in the low MFP group. Twenty-eight days after injection, most white spots had turned into pits (5–6 per molar) and only the high MFP group still contained 2 white spots per molar. We conclude that parenterally applied MFP is more potent in inducing enamel defects than NaF. Most white spots formed turn into pits by functional use of the dentition. The higher potency of parenteral MFP may be associated with sustained elevated F levels in the enamel organ by enzymatic hydrolysis of MFP by alkaline phosphatase activity.     

Cytotoxicity of Artemisinin,a Dimer of Dihydroartemisinin,Artemisitene and Eupatoriopicrin as Evaluated by the MTT and Clonogenic Assay

Artemisinin and its derivatives possess an endoperoxide bridge, which is thought to lead to the production of free-radical species. The cytotoxicity of some of these agents to a murine Ehrlich ascites (EN19) and a human HeLa S3 cancer cell line was determined using the MTT and the clonogenic assay. The MTT assay cannot distinguish between growth inhibition and cell killing, while the clonogenic assay detects actual cell death. The use of both assays to test a certain drug may give information on the mode of its cytotoxicity (i.e. growth inhibition versus cell killing). The endoperoxides artemisinin and the dimer of dihydroartemisinin showed much higher cytotoxicity in the MTT assay compared with the clonogenic assay. Thus these drugs mainly induced growth inhibition. For artemisitene and eupatoriopicrin, which possess an exocyclic methylene with alkylating properties, both tests yielded comparable results. For these compounds the MTT assay merely determined cell killing. For the reference drugs cisplatin and doxorubicin the MTT assay showed lower cytotoxicity than the clonogenic assay. This may be explained by the metabolic activity of cells that were clonogenically dead. Moreover, our experiments have shown that the MTT assay may lead to misinterpretations concerning the mode of action of certain drugs, when it is used as a substitute for the clonogenic assay.     

Spezifische physiologische und unspezifische psychische Effekte bei der Akupunkturtherapie des Reizdarmsyndroms: Ergebnisse einer randomisierten kontrollierten Studie

Background and aims

The aim was to evaluate the efficacy of acupuncture (AC) in patients with irritable bowel syndrome (IBS). We investigated psychological and neuroendocrinological parameters to meet the demands of the psychosomatic paradigm. In addition, we wanted to examine the impact of perception of bodily sensations on treatment response.

Methods

43 patients with IBS were randomly assigned to receive either AC (n = 22) or sham acupuncture (SAC) (n = 21) using the ”Streitberger needle„. Primary outcome measure was quality of life (QoL) measured with the functional digestive diseases quality of life questionnaire (FDDQL) and a general quality of life questionnaire (SF-36). QoL was measured before AC treatment (t1), after ten treatment sessions (t2) and three months after treatment (t3). Secondary outcome measures were parameters of the autonomic nervous system (ANS) which were evaluated with tilt-table manoeuvres at t1 and t2. Additionally, salivary cortisol was measured at t1 ant t2. Perception of bodily sensation was measured at t1 with the ”Perception of Bodily Sensation„ (PBS) questionnaire.

Results

QoL improved in both groups (p = 0,022). However, there were no group differences in QoL improvements between AC and SAC. Salivary cortisol decreased in both groups (F = 10,55; p = 0,006). However, the decrease was more pronounced in the AC group (F = 4,07; p = 0,033). Heart rate response decreased during orthostatic stress in the AC group while it increased in the SAC group (group difference: F = 9,23; p = 0,005), indicating an increased parasympathetic tone in the AC group. Improvement of pain was positively associated with increased parasympathetic tone in the AC group (r² =0,40; F = 10,1; p = 0,006), but not in the SAC group. High PBS was associated with lower QoL before and after treatment (p = 0,033).

Conclusions

The psychosomatic study design made it possible to detect differentiated acupuncture effects. QoL improvement seems to be due to unspecific effects and physiological changes are likely to be induced specifically by AC. Thus, different mechanisms may be involved in sham and real-AC mediated improvements. Patients with high PBS show a more unfavourable course of treatment independently of the kind of acupuncture treatment.     

Large sizes of vertebral body replacement do not reduce the contact pressure on adjacent vertebral bodies per se

Large implants for vertebral body replacement (VBR) have a large footprint, and are normally supported by stronger bone at the rim of the vertebral body. But they also necessitate a greater corpectomy defect in the vertebral body concerned. In order to study the effect of implant size on contact pressure on the adjacent vertebral bodies and thus the risk of implant subsidence, an osseoligamentous finite element model of the lumbar spine was employed. The VBR was inserted at the level of L4 and additionally stabilized by posterior spinal instrumentation. Flat and curved vertebral endplates, small and large corpectomy defects, different implant positions and axial preloads as well as normal and osteoporotic vertebral bodies were simulated. Contact pressures in the vertebral body are increased for a curved vertebral endplate in comparison with a flat one, they are increased when an additional implant preload was assumed, and they are usually decreased for an osteoporotic vertebra when compared to a non-osteoporotic one. In some cases the average contact pressures were higher for the small-sized VBR, in others for the large-sized one. Our results reveal that from the mechanical point of view, a small-sized VBR is not generally disadvantageous.