Comparing the ethical challenges of forgoing tube feeding in American and Hong Kong patients with advanced dementia.

OBJECTIVES: To develop a cross-cultural dialogue for enriching our understanding of how an ethical environment can be constructed in fostering tube-feeding decisions in patients with advanced dementia (AD). DESIGN AND DATA SOURCE: Drawing on the findings of two prospective case studies conducted in Boston and Hong Kong, this paper compares the decision-making patterns of forgoing tube feeding for AD patients and their emergent ethical dilemmas typified in a special dementia care unit in Boston (BCU) and a long-term care unit in Hong Kong (HKCU). FINDINGS: Differences in forgoing tube feeding decision are delineated in the two places. No-tube-feeding practice was sustained in BCU in two ways: advance decision-making with respect paid to the patient's wishes and advance proxy decision-making focused on patient comfort. With life preservation as the prevailing value in the Hong Kong medical system, only strong family request coupled with medical evidence of patient's ability to continue hand-feeding that tube feeding would be discontinued. All patients died with some form of artificial feeding. CONCLUSION: A paradigm shift of values underpinning the practice of forgoing tube feeding in the context of palliative care is observed in three aspects. First, the emphasis on prognostication based on biomedical markers in predicting the length of survival is shifted to a focus on the "diagnosis of dying". Second, the overriding concern in conventional medical practice with preserving life is shifting to an overriding concern of "what is best for the patient." Third, in the last days of life, the conventional approach of "trying to do everything for the patient" had shifted from a technological to a relational one. Palliative measures for relieving discomfort and providing a peaceful and dignified environment in which the patient could die are the primary concern. Although the predominant medical culture in Hong Kong is biomedical, voices from the patients and family members challenge this conventional practice, and suggest that the alternative model may be a better choice.

Snoezelen for dementia.

BACKGROUND: Snoezelen, multi-sensory stimulation, provides sensory stimuli to stimulate the primary senses of sight, hearing, touch, taste and smell, through the use of lighting effects, tactile surfaces, meditative music and the odour of relaxing essential oils (Pinkney 1997). The clinical application of snoezelen has been extended from the field of learning disability to dementia care over the past decade. The rationale for its use lies in providing a sensory environment that places fewer demands on intellectual abilities but capitalizes on the residual sensorimotor abilities of people with dementia (e.g. Buettner 1999, Hope 1998). Practitioners are keen to use snoezelen in dementia care, and some encouraging results have been documented in the area of promoting adaptive behaviours (e.g. Baker, Long 1992, Spaull 1998). However, the clinical application of snoezelen often varies in form, nature, principles and procedures. Such variations not only make examination of the therapeutic values of Snoezelen difficult, but also impede the clinical development of snoezelen in dementia care. A systematic review of evidence for the efficacy of snoezelen in the care of people with dementia is therefore needed to inform future clinical applications and research directions. OBJECTIVES: This review aims to examine the clinical efficacy of snoezelen for older people with dementia. SEARCH STRATEGY: "Snoezelen", "multi-sensory", "dement*", "Alzheimer*", "randomized control/single control/double control" were used as keywords to search seven electronic databases (e.g. MEDLINE, PsyLIT). The list of trials was compared with those identified from a search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group. SELECTION CRITERIA: All RCTs in which Snoezelen or multi-sensory programmes were used as an intervention for people with dementia were included in the review. Trial data included in the review were restricted to those involving people aged over 60 years suffering from any type of dementia, except one subject of Baker's study was aged below 60 years. DATA COLLECTION AND ANALYSIS: Only two RCTs fulfill the inclusion criteria for this systematic review. Two reviewers independently extracted the data from these two inclusion studies. Quantitative synthesis of the comparable data from the two trials was performed. MAIN RESULTS: Two trials were included. Both Baker (and Kragt examined the short-term values of snoezelen on the behaviours of people with dementia. Although the pooled results were insignificant, the trend was in the direction of favouring treatment (hence a negative value of the SMD). The standardized mean difference (SMD) was -1.22, with a 95% confidence interval (CI) (-4.08, 1.64). Kragt's result, weighted 47%, was significant in favour of treatment, with a SMD of -2.77 and a 95% CI (-4.24, -1.29). During the snoezelen session, Kragt's subjects presented significantly fewer apathetic behaviours (t=-8.22, p<0.01), fewer restless behaviours (t=-3.00, p=0.01), fewer repetitive behaviours (t=-.822, p<0.01), and fewer disturbances (t=-4.91, p<0.01). Baker's result was slightly not in favour of the treatment, with a SMD of 0.16 and a 95% CI (-0.41, 0.73). The control subjects touched objects/equipment more appropriately within the activity sessions than the subjects who participated in snoezelen sessions (F(1,47)=5.96, p=.001). Kragt did not examine the carryover and long-term effects of snoezelen, so only Baker's results were analysed. Baker used the Behavioural and Mood Disturbance scale (BMD), the REHAB, the CAPE and MMSE to assess patients mood, behaviour and cognition after (but not immediately after) four treatment sessions and eight treatment sessions. Some assessments were carried at home, some at day hospital. There were many subscores and mostly there were no differences between treatment and control. The following significant differences were found with benefit in favour of snoezelen compared with control after four sessions: apathy ezelen compared with control after four sessions: apathy score of the BRS (CAPE) (MD -3.00, 95%CIs -5.87 to -0.13, P=0.04), after eight sessions: mood score of the BRS (CAPE) (MD -2.60, 95%CIs -4.92 to -0.28, P=0.03), total score of the BRS (CAPE) (MD -6.92, 95%CIs -13.13 to -0.7, P=0.03), speech skills of the REHAB (MD 1.46, 95%CIs 0.01 to 2.82, P=0.03), psychomotor subscore of the cognitive assessment scale of CAPE (MD -3.12, 95%CIs -5.31 to -0.93, P<0.01). REVIEWER'S CONCLUSIONS: Two trials were reviewed. Although both studies examined the short-term values of snoezelen on people with dementia, it is not feasible to draw a firm conclusion at this stage, for two main reasons. Firstly, very limited data were available for analysis, thus limiting data inference and generalization. Secondly, different methodology and control conditions were adopted in the two trials. Such variations not only require a careful interpretation of results but also make the comparison of results across studies less valid. Hence, there is an urgent need for more systematic and scientific research studies to examine the clinical value of snoezelen for people with dementia. To our knowledge, there are four RCTs currently in progress. It is hoped that the data and results of these trials will enrich the systematic review of snoezelen for dementia in the next update.

Caring for dying children: a comparative study of nurses' experiences in Greece and Hong Kong.

The purpose of this transcultural descriptive study was to explore the subjective experiences of 63 oncology and critical care nurses who provide care to dying children in Greece and Hong Kong. Semistructured interviews were conducted with 39 Greek and 24 Chinese nurses who described their experiences and responses to the dying process and death of children. The data were analyzed qualitatively and quantitatively, and nurses' responses were compared for their work setting (oncology versus critical care) and their ethnic background (Greek versus Chinese). Findings revealed that most nurses experience a sense of helplessness when caring for a dying patient and difficulties in their communication with the child and parents during the terminal phase of the disease. The large majority acknowledge that the impending or actual death of a patient elicits a grieving process, which is characterized by a fluctuation between experiencing and avoiding loss and grief. Greek and Chinese nurses differ in their expression of their grief and how they attribute meaning to childhood death. Despite the suffering caused by multiple deaths, nurses report significant rewards from caring for chronically and acutely ill children, and the majority are satisfied with their job, despite the difficulties they encounter, in both countries, mostly as a result of shortage in personnel and cooperation problems with physicians.

Inhibition of glutathione disulfide reductase by glutathione.

Rat-liver glutathione disulfide reductase is significantly inhibited by physiological concentrations of the product, glutathione. GSH is a noncompetitive inhibitor against GSSG and an uncompetitive inhibitor against NADPH at saturating concentrations of the fixed substrate. In both cases, the inhibition by GSH is parabolic, consistent with the requirement for 2 eq. of GSH in the reverse reaction. The inhibition of GSSG reduction by physiological levels of the product, GSH, would result in a significantly more oxidizing intracellular environment than would be realized in the absence of inhibition. Considering inhibition by the high intracellular concentration of GSH, the steady-state concentration of GSSG required to maintain a basal glutathione peroxidase flux of 300 nmol/min/g in rat liver is estimated at 8-9 microM, about 1000-fold higher than the concentration of GSSG predicted from the equilibrium constant for glutathione reductase. The kinetic properties of glutathione reductase also provide a rationale for the increased glutathione (GSSG) efflux observed when cells are exposed to oxidative stress. The resulting decrease in intracellular GSH relieves the noncompetitive inhibition of glutathione reductase and results in an increased capacity (Vmax) and decreased Km for GSSG.

Morphine-induced tail erection: site of action.

Acute ablation techniques were used to localize morphine-induced tail erection (MITE) within the central nervous system of mice. Morphine produced no elevation of tails in mice whose spinal cord had been transected at the lower thoracic or lumbar levels. Decortication and high-level precollicular decerebration did not prevent MITE while morphine caused no tail response at all in low-level inferior collicular decerebrate mice. Lesions in various portions of the mesencephalon revealed that the degree of MITE was closely related to the size of the lesions of the central gray matter. The larger the lesion, the smaller the degree of tail elevation. MITE could not be elicited in mice when the mesencephalic central gray matter had been completely destroyed. Results indicate that morphine acts on the mesencephalic central gray matter producing tail erection and the pathway responsible for the reaction descends from the midbrain downward to the spinal cord.

Medullary unit responses to changes in local and hypothalamic temperatures in the cat.

Single unit activity was recorded with glass microelectrodes in the reticular formation of the medulla oblongata of cats lightly anesthetized with urethan, while medullary temperature was changed by surface irrigation with warm or cold artificial cerebrospinal fluid. In addition, water-perfusion thermodes were implanted over the preoptic anterior hypothalamus (POAH) region, and the effects of heating and cooling of the POAH on firing rate of medullary units were studied. One hundred and twenty-five temperature-sensitive neurons were studied in the medullary reticular formation. Out of these 125 neurons, 80 were warm-sensitive and 45 were cold-sensitive. Sixteen warm-sensitive medullary neurons were examined in responses to changes of POAH temperature. Ten units (62.5%) responded, and the remaining 6 units were not responsive to changes of the POAH temperature. Of 13 cold-sensitive neurons examined, 10 units (77.0%) responded. On the other hand, only 1 out of 7 (14.3%) temperature-insensitive neurons tested did respond to changes in the POAH temperature. These results suggest that the temperature signals sent out from thermosensitive structures in the hypothalamus might be transmitted to a major portion of temperature-sensitive neurons in the medullary reticular formation.

Response of temperature-sensitive medullary neurons to acetylcholine, norepinephrine, and 5-hydroxytryptamine.

Single unit activity was recorded by means of five-barrel micropipettes from temperature-sensitive neurons in the reticular formation of the medulla oblongata in urethanized cats. Acetylcholine (ACh), norepinephrine (NE) and 5-hydroxytryptamine (5-HT) were applied microiontophoretically to the immediate vicinity of the neurons. Both thermally sensitive and insensitive units responded to ACh (82.0%) and 5-HT (93.0%) by increasing discharge rate. Iontophoretically applied atropine, but not hexamethonium, antagonized the excitatory responses to ACh. NE was shown to have different effects on the medullary neurons. Most temperature-insensitive units were either nonresponsive (52.4%) or excited (28.6%) by NE, while a majority of warm-sensitive (61.8%) and cold-sensitive (55.6%) neurons were inhibited by NE. Iontophoretically application of the alpha-adrenergic blocking agent, phentolamine, or the beta-antagonists, propranolol, or sotalol, produced no effect on the inhibitory responses to NE. These results tend to support the current concept of the transmitter role of monoamines in thermoregulation.

Mechanisms of amitriptyline induced hypothermia in the rat.

Effects of amitriptyline on rectal temperature of male rats were studied at the ambient temperature of 25 degrees C. Drugs were administered intraperitoneally. Amitryptyline elicited a dose related hypothermia. The hypothermia was attenuated by phenoxybenzamine 10 mg/kg, haloperidol 2 mg/kg, diphenhydramine 5 mg/kg, atropine 20 mg/kg, and cyproheptadine 5 mg/kg. Propranolol, at a dose of 5 mg/kg, had no effect on the hypothermia. Theophylline 50 mg/kg and dibutyryl cyclic AMP 20 mg/kg inhibited the hypothermia produced by anitriptyline. Pretreatment with parachloroamphetamine (PCA), 2 or 5 mg/kg daily for 3 days, strongly antagonized the hypothermia. In addition, pretreatment with parachlorophenylalanine (PCPA), 100 mg/kg daily for three days, reduced the brain 5-hydroxytryptamine (5-HT) concentration to 20% of the control level and completely blocked the hypothermia response. When brain 5-HT concentration recovered to 50% of the control level in PCPA treated rats following the administration of 10 mg/kg 5-hydroxytryptophan (5-HTP) the hypothermia induced by amitriptyline was restored. However, the administration of 5-HT, 5 mg/kg, to PCPA treated rats did not increase brain 5-HT concentration or restore the amitriptyline induced hypothermia (AIH). Results suggest that amitriptyline interacts with several transmitter substances to produce hypothermia. Since the ability of amitriptyline to produce hypothermia was correlated with brain 5-HT content, 5-HT might play an important role in the mediation of AIH.

Effects of neuroleptics on morphine-induced tail erection in mice.

Morphine elicits dose-dependent tail erection in mice. Pretreatment of mice with atropine, phenoxybenzamine, propranolol, diphenhydramine, cyproheptadine or parachlorophenylalanine did not interfere with tail erection induced by morphone. Several neuroleptic drugs which are dopamine receptor blocking agents showed a clear antagonistic effect on morphine-induced tail erection (MITE). Haloperidol and penfluridol blocked MITE at doses which only produced a slight behavioral depression. Pimozide and chlorpromazine were less antagonistic than haloperidol and penfluridol and inhibited MITE only at doses which produced a marked behavioral depression. Results indicated that dopamine might be involved in tail erection induced by morphine. MITE in mice might be a useful model for the evaluation of neuroleptic drugs.