Predicting unconsciousness after propofol administration: qCON,BIS, and ALPHA band frequency power

During anesthesia induction with propofol the level of arousal progressively decreases until reaching loss of consciousness (LOC). In addition, there is a shift of alpha activity from parieto-occipital to frontal zones, defined as anteriorization. Whilst monitoring LOC and anteriorization would be useful to improve propofol dosage and patient safety, the current devices for anesthetic depth monitoring are unable to detect these events. The aim of this study was to observe LOC and anteriorization during anesthesia induction with propofol by applying electrodes placed in the frontal and parietal areas. Bispectral index (BIS) and quantium consciousness index (qCON) monitors were simultaneously employed. BIS? and qCON sensors were placed in the frontal and parieto-occipital regions of 10 alopecic patients who underwent anesthesia with propofol, alfentanil, and remifentanil. The initial biophase target of propofol was 2.5 mcg/mL which was gradually increased until reaching LOC. Wilcoxon signed-rank test was used to study differences in alpha power and qCON/BIS indices along the study; and Pk value to evaluate predictive capability of anteriorization of BIS, qCON, and alpha waves. Parietal BIS and qCON values became significantly higher than frontal values 15 min after loss of eye reflex. Anteriorization was observed with both monitors. Pk values for BIS and qCON were strongly predictive of frontal alpha absolute power. During anesthesia induction with propofol it is possible to identify anteriorization with BIS and qCON in the frontal and parieto-occipital regions. Both indices showed different patterns which need to be further studied.

     

Co-Construction of an Intervention Model Using Sports in a Rehabilitation Setting: A Collaboration Between Researchers and Practitioners

The objective of this article is to develop an explanatory model of how a rehabilitation intervention functions within a sports context. Participants include three Coach-Educators (CEs) who organize and set up a rehabilitation intervention using ice hockey. In order to develop the model, two focus groups using the co-modeling methodology of Basque and Pudelko (2004) were conducted. Based on their experiences, the CEs illustrated and modeled the functioning of their intervention. A concept mapping software was projected on a screen to follow the co-modeling in real time. The first discussion group provided a first draft of the model which served as a starting point for the second. The data were analyzed in light of the Theory of change (Weiss, 1998). The CEs report that the objective of the intervention is social integration. This objective can be achieved either through the interaction of the activity components (i.e., youth, group, CEs, ice hockey, structured aspects), or by the CEs’ interventions involving four mechanisms: strengthening self-esteem, moving focus from oneself to others, destigmatization, and learning of prosocial behaviors. Many factors, such as gender, expertise and participants’ experiences were identified as having a positive or negative effect on achieving the objective of the program. Practical considerations and future research avenues are presented. For example, practitioners who use sport in the context of rehabilitation should be familiar with the characteristics and difficulties of the adolescents in Youth Centers and have a clinical rationale in relation to the problem underlying the intervention and its objective.     

Sildenafil improves nocturnal penile erections in organic impotence.

We studied the effects of sildenafil on nocturnal penile erections. We prospectively evaluated 36 patients with organic or psychogenic impotence and 5 normal, potent men. All patients completed 3 sessions of consecutive nights using the RigiScan Plus device. The first two nights the patients were asked to take placebo before the session and to take 50 mg of sildenafil before the third session. In the organic impotence group the use of sildenafil induced a significant improvement in time of rigidity 60-100%, rigidity and tumescence activity unit values and rigidity and tumescence activity unit values per hour in the tip and base. In the psychogenic impotence group it caused significant improvement only in rigidity activity unit per hour in the tip. In the potent men, changes were statistically insignificant. Sildenafil improves nocturnal penile erectile activity in organic impotence. Our study shows that phosphodiesterase inhibitors can improve penile erections not induced by sexual stimulation.     

Spontaneous, but not induced, puberty permits adequate bone mass acquisition in adolescent Turner syndrome patients.

Lumbar L2-L4 bone mineral density (BMD) values were measured in 37 adolescent and young adult Turner syndrome patients. Nine had developed spontaneous puberty and had had regular menses since menarche (12.55 years +/- 1.17 years) to the time of BMD evaluation (14.96 years +/- 1.26 years). In the other 28, puberty was induced with increasing doses of oral ethinyl estradiol (2.5-10.0 microg/day, for 2 years) and later administration of estrogen/gestagen therapy up to the time of BMD evaluation. In 18, the adolescent group, menarche appeared at 14.68 years +/- 0.63 years and BMD was evaluated at 17.77 years +/- 0.70 years, and in the other 10, the young adult group, menarche appeared at 14.47 years +/- 0.53 years and BMD was evaluated at 20.90 years +/- 0.68 year. BMD values were in the normal range in those who had developed spontaneous puberty (Z score values, -0.24 +/- 0.22) and in the osteopenia range in those in whom puberty was induced (Z score values, -2.09 +/- 0.79 and -2.18 +/- 0.32 for the adolescent and young adult groups, respectively) p < 0.0001. Height Z score values were similar in all three groups (-3.45 +/- 0.77, -3.15 +/- 0.83, and -3.08 +/- 0.33, respectively). No significant differences in calcium intake or physical activity were found among groups. Neither the karyotype distribution nor growth hormone (GH) therapy (five in the spontaneous puberty and six in the induced puberty groups had been treated for a 3.5- to 4.4-year period) explained the differences in BMD values. Because the main difference between groups was the availability of estrogens to bone tissue from infancy to menarche and of estrogens/gestagens from then on up to the time of BMD evaluation, our results suggest that normal gonadal function from infancy to adulthood may be required for adequate bone mass peaking. Early detection of osteopenia and improvement in general measures for adequate bone mass peaking (calcium intake and physical activity) should be considered mandatory in the health care of these patients.     

Breaks invisible to the DNA damage response machinery accumulate in ATM‐deficient cells

After irradiation, ATM defective cells accumulate unrepaired double strand breaks (DSBs) for several cell divisions. At the chromosome level, unresolved DSBs appear as chromosome breaks that can be efficiently scored by using telomeric and mFISH probes. H2AX is immediately activated by ATM in response to DNA damage and its phosphorylated form, γH2AX, flanks the DSB through several megabases. The γH2AX‐labeling status of broken chromosome ends was analyzed in AT cells to check whether the DNA damage response was accurately taking place in these persistent DSBs. The results show that one quarter of the scored breaks are devoid of γH2AX foci in metaphase spreads from ATM‐deficient cells, and this fraction is significantly higher than in normal cells (χ² < 0.05). Accumulation of sensor and repair proteins at damaged sites is a key event in the cellular response to DSBs, so MRE11 labeling at broken ends was also analyzed. While all γH2AX foci scored at visible broken ends colocalize with MRE11 foci, all γH2AX‐unlabeled breaks are also devoid of MRE11‐labeling. The present results suggest that a significant subset of the AT long‐lived DSBs may persist as “invisible” DSBs due to deficient detection by the DNA damage repair machinery. Eventually the properly signaled DSBs will be repaired while invisible breaks may indefinitely accumulate; most probably contributing to the AT cells' well known genomic instability. © 2009 Wiley‐Liss, Inc.     

Clinical characteristics and outcomes of patients with vancomycin-susceptible Enterococcus faecalis and Enterococcus faecium bacteraemia in cancer patients

The purpose of this investigation was to compare the risk factors, clinical features and outcomes in cancer patients with bacteraemia caused by vancomycin-susceptible Enterococcus faecalis and E. faecium. A retrospective, observational 7-year study was carried out in a 450-bed, acute-care university-affiliated hospital. We performed univariate comparisons between the two groups and then multivariate analysis to identify patient risk factors for E. faecium isolation. Seventy-three patients were included in the analysis: 54 (74.0%) with bacteraemia caused by E. faecalis and 19 (26.0%) by E. faecium. The Simplified Acute Physiological Score (SAPS) value was significantly greater in E. faecium isolates (40.7 vs. 35.2; p = 0.009). Diabetes mellitus was more frequently diagnosed in patients with E. faecium bacteraemia (52.6% vs. 24.1%; p = 0.021). Prior penicillin exposure was more frequent in patients with E. faecium bacteraemia (68.4% vs. 29.6%; p = 0.003). There was a trend toward higher mortality in E. faecium bacteraemia patients (47.4% vs. 25.9%; p = 0.084). Independent patient risk factors for E. faecium isolation were prior penicillin exposure (odds ratio [OR], 6.479; p = 0.003) and SAPS > 34 (OR, 6.896; p = 0.009). When compared to E. faecalis bacteraemia, E. faecium bacteraemia in cancer patients is independently associated with more severe illness and prior use of penicillins; therefore, empiric treatment which would cover E. faecium should be considered in cancer patients suspected of having bacteraemia.     

Update on the anesthetic management of patients with malignant carcinoid syndrome

Carcinoid crisis during surgery can lead to severe hemodynamic alterations (hypo- and hypertension) and bronchospasm. Intravenous infusion of octreotide, preceded by preoperative subcutaneous administration, can allow such crises to be brought under control quickly. Given the high prevalence of carcinoid cardiopathy, which increases the risk of a crisis in these patients, a preoperative echocardiogram should be performed. General anesthesia combined with epidural blockade is effective in this context. Block onset should be gradual to avoid the development of hypotension, which is difficult to treat. The pharmacodynamic profile of remifentanil, its elevated potency, and low histamine releasing potential mean that this opioid offers novel advantages during general anesthesia.