1,721,064 research outputs found
Validation of a glucose control protocol in septic patients with continuous venous glucose measurement
No full textIntroduction: Blood glucose control in critically-ill patients is still on debate. A protocolized approach and a tight control limiting wasting of patient's blood are useful to correctly manage glycaemia (1).
Objective: Validation of glucose protocol (2) with a continuous blood glucose measurement (OptiScannerTM 5000).
Materials/Methods: OptiScannerTM was used in 6 patients providing glucose measurement every 15 minutes from a CVC dedicated line, net drawing 9.6 ml blood/24h. 330 ml of saline/24h were reinfused.
Target level was 80-160 mg/dL. Insulin infusion and kcal with nutritional support (NS) were recorded. Data are presented as median [interquartile range] (Sigmaplot11).
Results: 6 septic patients, SAPSII 28 [26-34], were studied for 319 hours (1277 measurements); 58 [40-69] hours for each patient (measurements/patient: 231 [172-265]). Blood glucose was at target for 96.6% of study time (120 [113-131] mg/dL). Overall only 3 measurements showed hypoglycemic episodes (78, 78, 69 mg/dL). Blood glucose was >160 mg/dL in 44 measurements (3%:168 [163-173] mg/dL). Insulin infusion rate was 2.2 [1.2-2.9] UI/h; kcal/day uptake was 1436 [649-1761].
Conclusion: The local glucose control protocol mantained euglycaemia in septic patients with high safeness (blood glucose <80 mg/dL, 0.2%).
Key points of the protocol are (2):
1. Lower blood glucose if >160 mg/dl before starting NS.
2. At the start of NS, provide insulin according to predicted stress status.
3. Targeting insulin need according to CHO/UI insulin observed.
OptiScannerTM 5000 seemed useful to validate the protocol.
References:
1) Dellinger RP Intensive Care Med. 2013;39(2):165-228.
2) Iapichino G Minerva Anestesiol. 2010;76(12):982-5
Tolerance of enteral feeding : from quantity to quality of gastric residual volume?
No full textNutritional support is essential in the management of critically ill patients; enteral nutrition is preferred to parenteral[1], as the latter may favour immune compromise, infections, higher costs and adverse outcome in some patients subsets. Moreover, many studies showed that this evidence is even more pronounced with the use of early enteral nutrition[2].
The major concerns with its use are the potential development of Upper Digestive Intolerance (UDI, i.e. presence of Gastric Residual Volumes, GRV, of 150-500 mL on two consecutive measurements, or >500 mL, or vomiting)[3] and the risk of aspiration of gastric content and pneumonia. Recently, some authors demonstrated that GRVs are poor markers of gastric aspiration in enterally fed critically ill patients[4], downsizing their role in the development of aspiration pneumonia.
To our knowledge there are no reports on the role that the presence of air in the stomach may play in the development of aspiration. The aim of our study was to test the association between UDI, presence of air and the development of pneumonia in enterally fed, critically ill patients
Nitric oxide metabolism and hypoxic vasodilation
No full textINTRODUCTION. When arterial O2 content is reduced, reflex increases in blood flow occur
in an attempt to restore local O2 supply. This "hypoxic vasodilation" involves excess levels of nitric oxide (NO). However, controversy persists as to whether this is due to increased NO production by NO synthase, increased NO generation from nitrite (by nitrite reductase), or
through decreased NO metabolism by mitochondria.
OBJECTIVES. To confirm that vasodilation is a NO-mediated response to tissue hypoxia,
and to clarify mechanisms underlying this reflex.
METHODS. Under isoflurane anaesthesia, spontaneously-breathing fluid-resuscitated male Wistar rats (250–350 g) underwent intravascular cannulation for blood pressure (ABP) monitoring, blood gas analysis, and fluid/drug administration. Tissue PO2 (tPO2) was determined using a luminescence probe placed in thigh muscle. Animals were allowed to stabilize for 300 after surgery and were then randomized to receive either room air or a hypoxic mixture (FiO2 0.125). In separate experiments both groups received, alone or in combination, a 100 continuous infusion of the non-selective NOS-inhibitor SEITU (1.5 mg/kg/min), the nitritedonor
NaNO2 (0.25 mg/kg/min), or vehicle. Data shown as mean ± SD. Statistics were
performed using 2-way repeated-measurement ANOVA and post-hoc Tukey’s test.
RESULTS. Hypoxia significantly reduced PaO2 from a baseline level of 10.8 ± 1.1 to
6.2 ± 2.8 kPa (p\0.001); tPO2 dropped from 6.1 ± 0.8 to 3.0 ± 0.4 kPa (p\0.001). None
of the interventions modified PaO2 or tPO2 levels.CONCLUSIONS. Hypoxic vasodilation is, at least in part, an NO-mediated process: hypoxia reduced ABP and tPO2, blunted the hypertensive effect of SEITU and accentuated the hypotensive effect of nitrite. We argue that, in hypoxia, NO derives only partially from NOS synthesis. Further insights into NO metabolism in hypoxia may help to better understanding mechanisms underlying haemodynamic adaptations.
REFERENCES. 1. Blitzer ML, et al. Am J Physiol (Heart Circ Physiol) 1996;271:H1182–5.
2. Allen JD, et al. Br J Pharmacol 2009;158:1653–4.
GRANT ACKNOWLEDGMENT. MU was supported by a Physiology Award of the Accademia
Nazionale dei Lincei (Roma)/Royal Society (London)
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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