Transcutaneous oximetry in clinical practice: consensus statements from an expert panel based on evidence

Transcutaneous oximetry (PtcO2) is finding increasing application as a diagnostic tool to assess the peri-wound oxygen tension of wounds, ulcers, and skin flaps. It must be remembered that PtcO2 measures the oxygen partial pressure in adjacent areas of a wound and does not represent the actual partial pressure of oxygen within the wound, which is extremely difficult to perform. To provide clinical practice guidelines, an expert panel was convened with participants drawn from the transcutaneous oximetry workshop held on June 13, 2007, in Maui, Hawaii. Important consensus statements were (a) tissue hypoxia is defined as a PtcO2 <40 mm Hg; (b) in patients without vascular disease, PtcO2 values on the extremity increase to a value >100 mm Hg when breathing 100% oxygen under normobaric pressures; (c) patients with critical limb ischemia (ankle systolic pressure of < or =50 mm Hg or toe systolic pressure of < or =30 mm Hg) breathing air will usually have a PtcO2 <30 mm Hg; (d) low PtcO2 values obtained while breathing normobaric air can be caused by a diffusion barrier; (e) a PtcO2 <40 mm Hg obtained while breathing normobaric air is associated with a reduced likelihood of amputation healing; (f) if the baseline PtcO2 increases <10 mm Hg while breathing 100% normobaric oxygen, this is at least 68% accurate in predicting failure of healing post-amputation; (g) an increase in PtcO2 to >40 mm Hg during normobaric air breathing after revascularization is usually associated with subsequent healing, although the increase in PtcO2 may be delayed; (h) PtcO2 obtained while breathing normobaric air can assist in identifying which patients will not heal spontaneously.

Effective patient blinding during hyperbaric trials

Hyperbaric medicine is applied for several disease states. Laboratory evidence is compelling but clinical efficacy remains incompletely validated. The standard by which supportive research is measured is termed evidence-based medicine, with results of randomized, blinded trials being most desirable. Blinding patients during hyperbaric exposure poses unique challenges. Few such studies are reported and confirmation of its success lacking. A study of patients suffering radiation-induced proctitis was conducted. It involved blinding of sham controls via a minimal air compression technique. Prior to unblinding 72 patients were surveyed using a standardized questionnaire to determine if they had been aware of their treatment allocation. Twenty of the 33 in the treatment group answered that they were in the treatment group, one answered sham and 12 did not know. Twenty-three of 39 in the sham group thought they were in the treatment group, two said sham and 14 did not know. A Chi-square analysis detected no relationship between what treatment was provided and what patients thought they received (p = 0.9058). Eliminating those who did not know, a Kappa statistic was p = 0.0299, indicating that there was no agreement beyond chance. Minimal air compression is an effective blinding tool for patients enrolled in hyperbaric trials.

Pharmacological management of inappropriate sexual behaviours: a review of its evidence, rationale and scope in relation to men with intellectual disabilities

BACKGROUND

The management of inappropriate sexual behaviours (ISB) including sexual offending is difficult, especially when the person treated has intellectual disabilities (ID). Psychological therapies are the accepted first line of treatment. Pharmacological treatments have also been advocated, particularly for people who have committed serious sexual offences. There is limited information on available drugs and evidence of their efficacy in the treatment of ISBs, in particular for people with ID.

METHODS

A literature search of electronic databases was undertaken. Pharmaceutical companies were contacted for unpublished information. Trials that included people with ID were systematically reviewed for the benefits and outcome in that population.

RESULTS

Androgen depleting drugs (cyproterone acetate, medroxyprogesterone acetate and luteinising hormone releasing hormone agonists) and psychotropic drugs (serotonin specific reuptake inhibitors and antipsychotics) are the two major categories of medications used in the treatment of ISBs. The majority of studies identified were open trials and most relied on self-report measures. Trials that included people with ID were few in number. Most trials indicated beneficial effects including reduction in sexually deviant fantasies and behaviours.

CONCLUSION

The quality of evidence base for the use of pharmacological agents in the treatment of ISBs is inadequate to justify their use in routine clinical practice. If used, they should only be a part of a comprehensive treatment programme and closely monitored. In addition, there are several clinical, ethical and legal issues to be addressed before considering pharmacological treatment of ISBs in people with ID.

The phenomenology and diagnosis of psychiatric illness in people with Prader-Willi syndrome

BACKGROUND

Psychotic illness is strongly associated with the maternal uniparental disomy (mUPD) genetic subtype of Prader-Willi syndrome (PWS), but not the deletion subtype (delPWS). This study investigates the clinical features of psychiatric illness associated with PWS. We consider possible genetic and other mechanisms that may be responsible for the development of psychotic illness, predominantly in those with mUPD.

METHOD

The study sample comprised 119 individuals with genetically confirmed PWS, of whom 46 had a history of psychiatric illness. A detailed clinical and family psychiatric history was obtained from these 46 using the PAS-ADD, OPCRIT, Family History and Life Events Questionnaires.

RESULTS

Individuals with mUPD had a higher rate of psychiatric illness than those with delPWS (22/34 v. 24/85, p<0.001). The profile of psychiatric illness in both genetic subtypes resembled an atypical affective disorder with or without psychotic symptoms. Those with delPWS were more likely to have developed a non-psychotic depressive illness (p=0.005) and those with mUPD a bipolar disorder with psychotic symptoms (p=0.00005). Individuals with delPWS and psychotic illness had an increased family history of affective disorder. This was confined exclusively to their mothers.

CONCLUSIONS

Psychiatric illness in PWS is predominately affective with atypical features. The prevalence and possibly the severity of illness are greater in those with mUPD. We present a 'two-hit' hypothesis, involving imprinted genes on chromosome 15, for the development of affective psychosis in people with PWS, regardless of genetic subtype.

The burden of mental disorders

In the last decade, there has been an increase in interest in the burden of chronic and disabling health conditions that are not necessarily fatal, such as the mental disorders. This review systematically summarizes data on the burden associated with 11 major mental disorders of adults. The measures of burden include estimates of prevalence, mortality associated with the disorders, disabilities and impairments related to the disorders, and costs. This review expands the range of mental disorders considered in a report on the global burden of disease, updates the literature, presents information on the range and depth of sources of information on burden, and adds estimates of costs. The purpose is to provide an accessible guide to the burden of mental disorders, especially for researchers and policy makers who may not be familiar with this subfield of epidemiology.

Equivalent-Forms Reliability of Printed and Spoken Versions of the NASA-TLX

Sixty-four participants provided subjective workload assessments after each of 15 trials of selected laparoscopic training tasks, including cannulation, ring transfer, and rope inspection. Half of the participants responded to the NASA-TLX using the traditional printed format with manual (written) responses. The remainder listened to auditory scale cues and made vocal responses. A comparison of the two formats revealed strong (r > .80) correlations and equivalent sensitivity to task and training effects, indicating that the vocal format may be a suitable substitute for traditional administration methods in the evaluation of surgical technology.

Dynamics of domain walls in magnetic nanostrips

We express the dynamics of domain walls in ferromagnetic nanowires in terms of collective coordinates, generalizing Thiele's steady-state results. For weak external perturbations the dynamics is dominated by a few soft modes. The general approach is illustrated on the example of a vortex wall relevant to recent experiments with flat nanowires. A two-mode approximation gives a quantitatively accurate description of both the steady viscous motion of the wall in weak magnetic fields and its oscillatory behavior in moderately high fields above the Walker breakdown.

A training syllabus for radiation protection in dental radiology

The EU Council Directive 97/43/EURATOM (MED) states that Member States shall ensure that adequate theoretical and practical training is provided for dental practitioners working with ionising radiation; this also includes the provision of continuing education and training programmes, post-qualification. The area of dental radiology is specifically mentioned in this legally binding document. The Department of Medical Physics and Bioengineering, St James's Hospital, Dublin, is particularly interested in the area of radiation protection training and routinely provides educational courses both at national and international levels. A recent review of their dental radiation protection course was undertaken in conjunction with a number of Principal Dental Surgeons within the Health Service Executive in Ireland. The revised course was delivered to over 200 dental staff members at two separate meetings during 2006. The response from attendees was very positive. It is proposed to extend this course to other dental professionals, working both in the Irish private and public health sectors in the future.

Factors associated with ownership and use of written asthma action plans in North-West Melbourne

PURPOSE

Written asthma action plans (WAAPs) have become a core component of asthma management in Australia. We investigated ownership, utilisation and factors associated with ownership of asthma action plans by caregivers.

METHODS

443/776 (57%) caregivers of children aged 2-14 years with asthma were identified from 32 GP clinics as part of a randomised controlled trial (RCT), and completed self-administered questionnaires.

RESULTS

Only 29% of participants owned a WAAP, while 13% possessed verbal instructions, and 56% had no plan. An asthma action plan for children, which was developed by a general practitioner (GP) was more likely to comprise verbal instructions (p = 0.001), while action plans developed by paediatricians were more likely to be written (p < 0.001). Just over one half of caregivers (59%) reported discussing their child's action plan the last time they visited their doctor for asthma. Factors associated with WAAP ownership included nights waking (p = 0.013), self reported severity (p = 0.001), and days lost from school (p = 0.037). Children who had seen a GP in the last 3 months for asthma, or who had been to the Emergency Department (ED) or hospital were more likely to possess a WAAP (p < 0.001). Caregivers who were less satisfied with their child's asthma control were more likely to own a WAAP (p = 0.037). Caregivers with any action plan found it useful and 82% reported using their action plan for management of an acute attack. However, caregivers with a WAAP were more likely to adhere to the plan for an acute attack compared to caregivers with verbal instructions (OR = 4.5, p < 0.05). Caregivers with a WAAP were more knowledgeable about asthma (p = 0.002), better able to recognise the difference between preventer and reliever medications (p = 0.01), and better able to recognise an asthma attack (p = 0.006).

CONCLUSIONS

Ownership of WAAPs in this group was still too low. Importantly, caregivers with written instructions were more knowledgeable about asthma and more likely to report following the action plan during an asthma attack.

Asymmetric domain nucleation and unusual magnetization reversal in ultrathin Co films with perpendicular anisotropy

We report unexpected phenomena during magnetization reversal in ultrathin Co films and Co/Pt multilayers with perpendicular anisotropy. Using magneto-optical Kerr microscopy and magnetic force microscopy we have observed asymmetrical nucleation centers where the reversal begins for one direction of the field only and is characterized by an acute asymmetry of domain-wall mobility. We have also observed magnetic domains with a continuously varying average magnetization, which can be explained in terms of the coexistence of three magnetic phases: up, down, and striped.

Selective serotonin reuptake inhibitor use associates with apathy among depressed elderly: a case-control study

BACKGROUND

It has been reported for over the past decade that the use of selective serotonin reuptake inhibitors (SSRI's) may associate with the emergence of apathy. The authors hypothesized that depressed patients treated with SSRI's would show more signs of apathy than patients treated with non-SSRI antidepressants. This case control study was conducted to investigate the possibility of the association between SSRI use and the occurrence of apathy.

METHODS

Baycrest Centre for Geriatric Care's Day Hospital Database of elderly depressed patients who received antidepressants was divided into 2 groups depending on antidepressant use at discharge: SSRI user group-SUG, and non-SSRI user group-NSUG. Apathy scales developed by the authors were selected from the Geriatric depression Scale (GDS) and the Hamilton Rating Scale for Depression (HAMD), and were titled as GDS-apathy subscale (GAS) and HAMD-apathy subscale (HAS). Demographic data, baseline apathy, underlying medical conditions and medication use were studied. Proportion, analysis of variances, Chi-square test, odds ratio with 95% confidence interval were reported.

RESULTS

Among 384 patients (160 SUG and 224 NSUG), mean GDS and HAM-D at discharge were 12.46 and 10.61 in SUG, and were 11.37 and 9.30 in NSUG, respectively. Using GAS for apathy assessment, 83.7% of patients in SUG and 73.4% in NSUG stayed apathetic at discharge. As evaluated by HAS, 44.2% of patients in SUG and 36.5% in NSUG stayed apathetic. SSRI use was not a predictor of apathy at admission, while it was at discharge, p = 0.029. The SUG showed more patients with apathy than that found in NSUG (adjusted OR = 1.90 (1.14-3.17). Age 70-75 years tended to be a predictor for the apathy (p = 0.058). Using HAS, age 70-75 years and living situation were associated with apathy at discharge, p = 0.032 and 0.038 respectively.

CONCLUSION

Even though depression was improved in elderly patients receiving antidepressants, apathy appeared to be greater in patients who were treated with SSRI than that found in patients who were not. Frontal lobe dysfunction due to alteration of serotonin is considered to be one of the possibilities.

The course and outcome of psychiatric illness in people with Prader-Willi syndrome: implications for management and treatment

BACKGROUND

This study is part of a larger UK-wide study investigating psychiatric illness in people with Prader-Willi syndrome (PWS), and describes the longitudinal aspect of psychiatric illness, in particular psychotic illness, and examines the use and role of psychotropic medication.

METHOD

A total of 119 individuals with genetically confirmed PWS were included in the study. An informant-based questionnaire was administered for each participant to screen for a history of psychopathology. Those who screened positive were visited at their homes to obtain further information. This assessment included a full psychiatric history and mental state examination using the Psychiatric Assessment Schedule for Adults with Developmental Disability and the Operational Criteria Checklist for psychotic and affective illness to collect information regarding phenomenology and course of illness, and a modified life events questionnaire. At the end of the study period, informant-based telephone interviews were again carried out, up to 2.5 years after the initial screening. Information regarding medication usage was collected.

RESULTS

The results confirm previous findings that psychiatric illness in people with PWS resembles an affective disorder. Individuals with the maternal uniparental disomy genetic subtype had a more severe course of illness than those with the deletion genetic subtype in terms of a greater risk of recurrence, more episodes, higher incidence and a possibly poorer response to medication with more side-effects. Individuals with a recurrent episode during the follow-up period had a poorer course of illness. Selective serotonin reuptake inhibitor medication is frequently used, and beneficial effects may reflect fundamental pathological processes in PWS. Mood-stabilizing medication was found to be of little benefit and reasons for this are examined.

CONCLUSION

The longitudinal course of psychiatric illness and response to medication in people with PWS is fully described. Further research is needed regarding the effect of psychotropic medications, particularly mood-stabilizing medication. These data will enable informed decisions to be made regarding management options and provide information on the possible long-term outcome of illness.

Wrinkling of a bilayer membrane

The buckling of elastic bodies is a common phenomenon in the mechanics of solids. Wrinkling of membranes can often be interpreted as buckling under constraints that prohibit large-amplitude deformation. We present a combination of analytic calculations, experiments, and simulations to understand wrinkling patterns generated in a bilayer membrane. The model membrane is composed of a flexible spherical shell that is under tension and that is circumscribed by a stiff, essentially incompressible strip with bending modulus B . When the tension is reduced sufficiently to a value sigma , the strip forms wrinkles with a uniform wavelength found theoretically and experimentally to be lambda=2pi(B/sigma)(1/3). Defects in this pattern appear for rapid changes in tension. Comparison between experiment and simulation further shows that, with larger reduction of tension, a second generation of wrinkles with longer wavelength appears only when B is sufficiently small.

Melatonin and sleep disorders associated with intellectual disability: a clinical review

BACKGROUND

Melatonin is used to treat sleep disorders in both children and adults with intellectual disability (ID), although it has no product license for such use. The evidence for its efficacy, potential adverse effects and drug interactions are reviewed in the context of prescribing to people with ID.

METHODS

A literature search was performed using multiple electronic databases. More literature was obtained from the reference lists of papers gathered through the searches.

RESULTS

Most of the studies were uncontrolled and the few controlled trials available were of small size. Melatonin appears effective in reducing sleep onset latency and is probably effective in improving total sleep time in children and adolescents with ID. It appears to be ineffective in improving night-time awakenings. Melatonin is relatively safe for short-term use. Its safety for long-term use is not established. Potential drug interactions, possible effects on puberty and concerns regarding the use of melatonin in epilepsy, asthma and depressive disorders are discussed.

CONCLUSIONS

Melatonin appears to be an effective sleep-initiator for children and adolescents with ID and probably has a similar effect for adults. There may be heterogeneity of response depending on the nature of the sleep problem and cause of the ID or associated disabilities. Further studies are necessary before firm conclusions can be drawn and guidelines for the use of melatonin for people with ID formulated.

Influence of annual climate variability on design and operation of waste stabilisation ponds for continental climates

WSPs are widely used in North America, and offer huge potential for other continental climate regions. The standard design and operating protocol is robust even at high latitudes, but may be conservative elsewhere. A simple model based on first-order kinetics for biochemical oxygen demand (BOD) is used to consider some alternative design and operating protocols, using long-term daily climate records for cities across continental central Asia. Options include changing the discharge period; retaining treated water in the pond over the winter; and changing the facultative pond loading. Annual variability in climate parameters has a major effect, in particular on the date at which treated wastewater meets appropriate standards for discharge or re-use: the earlier the discharge, the greater the variability in effluent quality. Skilful management of these systems may therefore be required to maximise their performance. While current models require development, it is clear modelling could provide tools and guidelines that would allow the design of continental climate WSP to be tailored to specific regional and local climate conditions.

An evidence-based appraisal of the use of hyperbaric oxygen on flaps and grafts

Hyperbaric oxygen has been advocated, both as an adjunctive or primary form of treatment, for a variety of disorders, including gas gangrene, osteoradionecrosis, and carbon monoxide poisoning. It has also been used to improve ischemic wounds before skin grafting and to support ischemic flaps. In this review, we analyze the available literature that investigates the use of hyperbaric oxygen for composite grafts, skin grafts, random flaps, distant flaps, and free flaps. An appraisal of the level of evidence for each of these uses of hyperbaric oxygen is offered. Although there are a significant amount of animal data supporting the application of hyperbaric oxygen for grafts and flaps, there is very little clinical information other than case reports and series to sustain its choice over other modalities of therapy. Multicenter prospective clinical studies are clearly needed comparing hyperbaric oxygen to other mechanical or pharmacologic interventions to improve wound healing for grafting or to support flap survival.

CD36 expression and its relationship with obesity in blood cells from people with and without Prader-Willi syndrome

Although Prader-Willi syndrome (PWS) has been linked to the loss of function of imprinted genes in 15q11q13, very little is known about the pathogenesis. Using quantitative real-time PCR, we have confirmed the previous observation of an abnormality of CD36 expression in cells with maternal uniparental disomy 15, obtained from a proband with mosaicism for PWS, by demonstrating reduced expression levels in blood cells from a series of non-mosaic probands with PWS. Furthermore, we have extended these observations to show that CD36 expression in a non-PWS population is inversely correlated with body mass index but that this correlation does not hold in PWS. CD36 which maps to 7q11.2 is the first gene outside the 15q11q13 region whose level of expression appears to be reduced in people with PWS. Low CD36 expression levels in PWS point to an abnormal control of lipid and glucose homeostasis which may explain the insatiable hunger in these patients.