Dry heat, moist heat and body fat: are heating modalities really effective in people who are overweight?

Surface heating modalities are commonly used in physical therapy and physical medicine for increasing circulation, especially in deep tissues, to promote healing. However, recent evidence seems to indicate that in people who are overweight, heat transfer is impaired by the subcutaneous fat layer. The present investigation was conducted on 10 subjects aged 22-54 years, whose body mass index averaged 25.8+/-4.6. Subcutaneous fat above the quadriceps muscle varied from 0.51 to 0.86 cm of thickness. Three heating modalities were examined: the application of dry heat with a commercial chemical heat pack, hydrocollator heat packs (providing a type of moist heat), and a whirlpool, where conductive heat loss through water contact would be very high. The temperature of the skin and the temperature in the muscle (25 mm below the skin surface) were assessed by thermocouples. The results of the experiments showed that for heating modalities that are maintained in skin contact for long periods of time, such as dry heat packs (in place for 6 hours), subcutaneous fat did not impair the change in deep muscle temperature. In contrast, when rapid heat modalities were used, such as the hydrocollator and the whirlpool (15 minutes of sustained skin contact), the transfer of heat from the skin to deep muscle was significantly impaired in people with thicker subcutaneous fat layers. We observed that the greater the impairment in heat transfer to muscle from skin covered by body fat, the warmer the skin temperature increase during the modality.

Does skin moisture influence the blood flow response to local heat? A re-evaluation of the Pennes model.

Pennes first described a model of heat transfer through the limb based only on calories delivered from a heat source, calories produced by metabolism and skin blood flow. The purpose of this study was to determine the effect of a moist versus a dry heat source on the skin in eliciting a blood flow response to add data to this model. Ten subjects were examined, both male and female, with a mean age of 32.5 +/- 11.6 years, mean height of 172.8 +/- 12.3 cm, and mean weight of 77.6 +/- 19.5 kg. Skin temperature was measured by a thermocouple placed on the skin and skin blood flow measured by a laser Doppler flow meter. The results of the experiments using a dry heat pack (commercially available chemical 42 degrees C cell dry heat source), moist hydrocollator pack (72.8 degrees C) separated from the skin by eight layers of towels, and whirlpool at 40 degrees C, showed that moist heat caused a significantly higher skin blood flow (about 500% greater) than dry heat (p < 0.01). Most of the greater increase in skin blood flow with moist heat was due to the greater rate of rise of skin temperature with moist versus dry heat while some of the increase in blood flow was due to the moisture itself. This could either be related to the greater heat flux across the skin with moist air or due to changing the ionic environment around skin thermo receptors by keeping the skin moist during heating. Skin thermo receptors are believed to be temperature sensitive calcium gated channels in endothelial cells which couple calcium influx to a release of nitric oxide. If true, reducing moisture in the skin might have the effect of altering ionic flux through these receptors. A correct model of skin heat flux should therefore take heat moisture content into consideration.

The transfer of current through skin and muscle during electrical stimulation with sine, square, Russian and interferential waveforms.

Electrical stimulation is a commonly used modality for both athletic training and physical therapy. However, there are limited objective data available to determine the waveform which provides the maximum muscle strength as well as minimizing pain. In the present investigation, two groups of subjects were examined. Group 1 was composed of six males and four females and group 2 was composed of three male and three female subjects. The first series of experiments investigated muscle strength with stimulation at currents of 20, 40 and 60 milliamps using sine, square, Russian and interferential waveforms evaluating strength production and pain as outcomes. The second phase of experiments compared the effect of the different waveforms on current dispersion in surface versus deep muscle electrodes with these same waveforms. The results of the experiments showed that sine wave stimulation produced significantly greater muscle strength and significantly less pain than square wave, Russian or interferential stimulation at that same current. The most painful stimulation was square wave. Strength production was greatest with sine wave and least with Russian and interferential. An explanation of these findings may be the filtering effect of the fat layer separating skin from muscle. The highly conductive muscle and skin dermal layers would form the plates of a capacitor separated by the subcutaneous fat layer providing an RC filter. This filtering effect, while allowing sine wave stimulation to pass to the muscle, reduced power transfer in square wave, Russian and interferential stimulation is observed.

Effects of a 2-, 3- and 4-electrode stimulator design on current dispersion on the surface and into the limb during electrical stimulation in controls and patients with wounds.

Electrical stimulation is a widely used modality in the field of physical therapy and exercise physiology. The most common method for the application of electrical stimulation is a two-electrode system where one electrode is the source and the other is a reference. However, recent studies report that a more effective delivery system can be achieved if more than two electrodes are used. In the present investigation, the circuitry to deliver electrical stimulation through a 2-, 3- or 4-electrode delivery system was designed. The system was evaluated by its ability to deliver current on the surface of the skin as well as deep into the quadriceps muscle in six control subjects and in and around wounds in six other subjects. The results of the experiments showed that much better depth of penetration was achieved in a 4-electrode system (one electrode was on the opposite side of the limb and three electrodes were on top of the limb) than in either a 2- or a 3-electrode delivery system. In non-wounded skin, given the same current from the stimulator, the current in the quadriceps muscle was found to be double with a 4-electrode versus a 2-electrode system. In wounds, this same finding was seen. Here, blood flow, an indicator of the effectiveness of electrical stimulation in wounds, was three times higher if a multi-channel stimulator was used versus a 2-channel stimulator. Thus a multi-channel electrical stimulation system is more effective than a 2-electrode system.

Standing outside the interview process? The illusion of objectivity in phenomenological data generation.

This paper challenges the idea of researcher objectivity as a necessary feature of phenomenological interviewing by contrasting the philosophies of Husserl and Heidegger in relation to the way they influence the interview process, the generation of data and the role of the researcher in the interview. The discussion demonstrates how a failure to distinguish between Husserlian transcendental phenomenology and Heideggerian hermeneutic phenomenology results in methodological confusion. The interviewing process is analysed with regard to researchers' preconceptions, interviewer bias, the pursuit of objectivity and the relevance of subjectivity in phenomenological research. Quality indicators, such as adequacy of description and the elucidation of researchers' preconceptions, are discussed and illustrated with examples from the authors' doctoral studies.

Clinical effectiveness in the post-anaesthesia care unit: how nursing knowledge contributes to achieving intended patient outcomes.

Clinical effectiveness in the post-anaesthesia care unit: how nursing knowledge contributes to achieving intended patient outcomes This paper reports part of an ongoing study on how nursing knowledge develops in practice and influences patient outcomes. The practice focus is post-anaesthesia nursing, an area which has been under-represented in nursing research. A qualitative approach was used to explore narrative data, collected by in-depth interviews, with 32 experienced post-anaesthesia nurses. Data analysis and interpretation were informed by a phenomenological perspective consistent with a research focus on individual experiences. Interpretation of the narratives gave rise to a description of knowledge development which occurred as nurses gained experience, drew on the available knowledge base, and used knowledge in practice. This led to the identification and description of 'referential' and 'effective' types of knowledge. Referential knowledge comprises the variety of external knowledge sources available to inform practice. When referential knowledge was incorporated into the personal knowledge of the individual nurse in everyday practice, it was transformed into effective knowledge which was used by nurses to achieve desired patient outcomes. The study findings indicate that nurses used effective knowledge as evidence for decision making and interventions in everyday practice. The key finding of the study is that effective nursing knowledge requires practice for its development.

Methodological issues in the development and use of instruments to assess patient nutritional status or the level of risk of nutritional compromise.

This paper presents the results of an appraisal of the evidence for the effectiveness of methods of nutritional assessment currently in use by nurses and from this develops concepts which may be applied to many areas of nursing practice. The paper first shows how the approach to nutritional assessment by nurses has changed over time, producing the present search for methods which are relatively quick and easy to use. It then describes the limited nature of the evidence of effectiveness of these methods and considers the reasons for this situation. It suggests that the difficulty of validation is an important factor and describes the three most common approaches to validation, showing how problems arise from lack of clarity in the definition of terms and the assumption of a simple relationship between the level of risk of nutritional compromise and actual nutritional status. In conclusion, it is suggested that these difficulties illustrate principles applicable to many areas of nursing care, and a definition of 'segments' of care processes, each with well-defined purposes and outcome measures, is proposed. Such an approach will help to demonstrate the complexity and value of nursing activity.

Joint working. One for the boys.

An increase in the number of complications following male circumcisions performed by non-professionals led to the establishment of a special clinic for religious circumcisions. The clinic is jointly funded by health organisations, the local authority and the Muslim community. Parents pay 45 pounds for the service, which is acceptable to the local Muslim community.

Linking knowledge and practice through teacher-led placements for students.

Project 2000 and diploma level education for pre-registration students have been criticised for their lack of emphasis on practical nursing skills. This article describes how teacher-led placements can equip these students with the requisite practical skills in a reflective manner that enables them to relate theory to practice. The author argues that only through critical thinking can students obtain a relevant understanding of the knowledge which underpins both theory and practice.

Toward 2001. The recovery room revisited.

Recovery room nursing is more accurately described by the term "post-anaesthesia nursing." Issue of patient safety, standards of care and staff training in the recovery room have been highlighted by the Association of Anaesthetists in two reports. Current training and education provision for post-anaesthesia nurses is provided by combined operating department nursing and anaesthetic nursing curricula (ENBI182:83). There are few courses designed for nurses who specialize in the care of the post-anaesthesia patient.

Treatment of early rheumatoid arthritis with rifampicin.

Following a report that seven of 20 patients with rheumatoid arthritis (RA) had come into clinical and laboratory remission after treatment with rifampicin, and that six of the seven responders had a disease duration of less than three years, 21 patients with classical or definite RA of recent onset were treated with 600 mg rifampicin and 300 mg isoniazid daily for six months. Fourteen of 21 patients completed six months' treatment, but there was no significant improvement in the mean values of the clinical and laboratory parameters measured. The improvement suggested by preliminary studies in patients with early RA is not seen in this larger group. In patients with a disease duration of less than 18 months, however, there was a significant decrease in the erythrocyte sedimentation rate and the serum concentrations of C reactive protein after treatment for six months, although there was no significant clinical improvement. Future studies of this drug in patients with RA should concentrate on this group.

Drug-induced rheumatic syndromes. Diagnosis, clinical features and management.

In order to avoid inappropriate therapy and prolonged morbidity, it is important to recognise when a patient's rheumatic complaints are due to drugs. However, this is often difficult because of the large number of drugs that have been implicated and the diversity of clinical presentations. Arthropathy may be seen with several different syndromes, including drug-induced lupus erythematosus (DILE), serum sickness and gout. The most widely reported of these is DILE, which usually develops after some months or even years of drug therapy. While many authors do not specifically require their presence for the diagnosis of DILE, antinuclear antibodies have been detected in the great majority of reported patients with DILE, whatever the causative drug. In contrast, patients who develop arthropathy soon after commencing a drug rarely have antinuclear antibodies and appear to be distinct from patients with DILE. Apart from arthropathy, a number of other syndromes that appear to have an immunological basis may be induced by drugs. Cutaneous vasculitis is not uncommon and drugs are frequently considered to be the aetiological factor. Whether drugs may cause larger vessel systemic vasculitis is less certain. Rarely, polymyositis and scleroderma-like syndromes have been associated with drug therapy. Corticosteroid-induced osteoporosis is a complication of all the corticosteroid preparations that are widely used at present. However, the development of deflazacort, a so-called 'bone-sparing' steroid, has raised the possibility that the effect of corticosteroids on bone may be separable, at least in part, from the other actions of these drugs. Data have been conflicting with regard to whether there is a 'safe' dose of corticosteroid. Similarly, it is unclear whether prophylactic therapy with agents such as calcium, fluoride and vitamin D is beneficial. Nonetheless, recent findings suggest that approaches will be developed to minimise the risk of osteoporosis in patients who require corticosteroids. There are a number of other ways in which drugs may affect bones. Osteomalacia is a well-known but uncommon complication of treatment with anticonvulsants and occasionally other drugs. The mechanism probably relates to the induction of hepatic enzymes and the consequent increased metabolism of vitamin D in patients with borderline levels initially. Osteosclerosis may also result from drug therapy; usually with fluoride or retinol (vitamin A) and its analogues. With continued research, the true spectrum of drug-induced rheumatic syndromes should become more clearly defined.(ABSTRACT TRUNCATED AT 400 WORDS)

Reflex sympathetic dystrophy associated with squamous cell carcinoma of the lung.

Reflex sympathetic dystrophy was the presenting feature in an otherwise occult case of non-metastatic squamous cell carcinoma of the lung which improved on surgical removal of the primary tumour. Reflex sympathetic dystrophy, therefore, should be considered an occasional manifestation of a paraneoplastic syndrome warranting a thorough search for underlying malignancy.

Two distinct quinidine-induced rheumatic syndromes.

Of seven patients with quinidine-induced polyarthropathy, four had positive antinuclear antibodies and could be considered to have had quinidine-induced lupus erythematosus. The remaining three patients had milder symptoms, which occurred soon after the start of quinidine therapy, and did not have antinuclear antibodies. To confirm the association, the latter three patients were rechallenged with quinidine therapy, which caused recurrence of symptoms within 1 week. Antihistone antibodies, which are characteristic of drug-induced lupus erythematosus associated with procainamide and hydralazine therapy, were detected in all patients with quinidine-induced lupus erythematosus. An unusual characteristic of antihistone antibodies seen in two patients was the presence of high levels of IgG antibodies to histone H1 as well as H2A.H2B and H3.H4 complexes, without antibodies to the individual core histones.

Oncogenic hypophosphatemic osteomalacia associated with a giant cell tumour of a tendon sheath.

We report a case of oncogenic hypophosphatemic osteomalacia, a rare form of osteomalacia, secondary to a diffuse giant cell tumour of tendon sheath. Possible pathogenic factors are discussed in the light of previously described clinical and experimental observations.

Minimal breastfeeding.

Current advice to breastfeeding mothers is that breasts must be emptied regularly and frequently to help maintain lactation. A method of maintaining lactation, minimal breastfeeding, in which mothers nurse once or twice a day without expressing the breast between breastfeedings was investigated. A convenience sample of 30 mothers using minimal breastfeeding was interviewed monthly until weaning. These mothers used minimal breastfeeding as a method of slow weaning, a way to combine breastfeeding and work, and a means of comfort-nursing older infants. In all cases, weaning occurred because the mother or the infant chose to wean, not because of insufficient milk. The authors conclude that for working mothers who cannot express between feeds, breastfeeding can still be maintained, and that minimal breastfeeding is an important alternative to weaning.

Pharmacokinetics and effects of isoxicam on renal function in patients with renal insufficiency.

The pharmacokinetics of isoxicam, a new non-steroidal anti-inflammatory drug, were studied in 20 osteoarthritis patients with varying degrees of renal insufficiency. A wide variation in pharmacokinetic parameters was seen between individuals but there was no suggestion that renal function influenced pharmacokinetics. Steady state plasma isoxicam concentrations varied from 20 micrograms/ml to 130 micrograms/ml, while the plasma half-life varied from 23 hours to 58 hours. Despite a reduction in urinary prostaglandin E2 excretion, isoxicam administration did not alter renal function over a 4-week period.

Successful breast feeding: the mother's dilemma.

A content analysis of 141 articles on breast feeding by discipline revealed differences in the factors considered necessary for breast feeding success and in the criteria used to determine success. Whereas medical articles focused on maternal factors prenatally and infant health post-natally, or the length of time breast feeding was maintained, lay articles focused on the relationship of the mother with her infant (the nursing couple) and the mother's ability to manage breast feeding within the family context. The implications of this discrepancy for nursing practice and research are discussed.