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The deployment of an intensive care unit with a forward British military field hospital to the conflict in Iraq in March 2003 is described. The 10 bedded unit treated 47 patients in the first month of activity. Thirty seven were adults and 10 were children. Forty two (89%) were trauma patients, mostly related to the conflict. Sixty eight percent of patients were ventilated and mortality to discharge was 6%. Mean bed occupancy was five beds and the mean duration of patient stay was 3.3 days. The difficulties of the working environment are described including the problems of a desert climate and close proximity to a conflict. Several critical incidents occurred including total power failure, extreme ambient temperatures and gas attack alarms. Despite these challenges, the facility attempted to provide a standard of intensive care similar to that seen in UK practice.

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Major neurochemical effects of methamphetamine include release of dopamine (DA), serotonin (5-HT), and norepinephrine (NE) via a carrier-mediated exchange mechanism. Preclinical research supports the hypothesis that elevations of mesolimbic DA mediate the addictive and reinforcing effects of methamphetamine and amphetamine. This hypothesis has not been adequately tested in humans. Previous in vivo rodent microdialysis demonstrated that the high affinity DA uptake inhibitor, GBR12909, attenuates cocaine- and amphetamine-induced increases in mesolimbic DA. The present study determined the ability of GBR12909 to attenuate amphetamine-induced increases in striatal DA as measured by [(11)C]raclopride continuous infusion positron emission tomography (PET) scans in two Papio anubis baboons. [(11)C]Raclopride was given in a continuous infusion paradigm resulting in a flat volume of distribution vs. time for up to 45 min postinjection. At that time, a 1.5 mg/kg amphetamine i.v. bolus was administered which caused a significant (30.3%) reduction in the volume of distribution (V(3)"). The percent reduction in the volume of distribution and, hence, a measure of the intrasynaptic DA release ranged between 22-41%. GBR12909 (1 mg/kg, slow i.v. infusion) was administered 90 min before the administration of the radiotracer. The comparison of the volume of distribution before and after administration of GBR12909 showed that GBR12909 inhibited amphetamine-induced DA release by 74%. These experiments suggest that GBR12909 is an important prototypical medication to test the hypothesis that stimulant-induced euphoria is mediated by DA and, if the DA hypothesis is correct, a potential treatment agent for cocaine and methamphetamine abuse. Furthermore, this quantitative approach demonstrates a way of testing various treatment medications, including other forms of GBR12909 such as a decanoate derivative.

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UNLABELLED: Nicotinic acetylcholine receptors (nAChRs) have been implicated in a variety of central processes, such as learning and memory and analgesia. These receptors also mediate the reinforcing properties of nicotine in tobacco products and are increased in postmortem samples of brains of smokers. On the other hand, brains of individuals who have died from dementia of the Alzheimer type show abnormally low densities of nAChRs. In this study, the distribution and kinetics of [(+/-)-exo-2-(2-[18F] fluoro-5-pyridyl)-7-azabicyclo[2.2.1]heptane (18F-FPH), a high-affinity nAChR agonist, was evaluated in a baboon using PET. METHODS: After intravenous injection of 5 mCi [185 MBq] 18F-FPH into a 25-kg anesthetized baboon, sequential quantitative tomographic data were acquired over a period of 150 min. Regions of interest were placed and time-activity curves were generated. Brain kinetics of the radiotracer were calculated, and the in vivo regional binding in the baboon brain was compared with the known in vitro regional distribution of nAChRs in the rat and human brain. RESULTS: Brain activity reached a plateau within 60 min after injection of the tracer, and the binding was reversible. Elimination of 18F-FPH was relatively rapid from the cerebellum (clearance t[1/2] = 3 hr), intermediate from the hypothalamus/midbrain (t[1/2] = 7 hr) and slow from the thalamus (t[1/2] = 16 hr). Radioactivity due to 18F-FPH at 130 min postinjection was highest in the thalamus and hypothalamus/midbrain, intermediate in the neocortex and hippocampus and lowest in the cerebellum. Subcutaneous injection of 1 mg/kg cytisine 45 min after injection of the radiotracer reduced brain activity at 130 min by 67%, 64%, 56% and 52% of control values in the thalamus, hypothalamus/midbrain, hippocampus and cerebellum, respectively. The regional binding of 18F-FPH at 130 min was highly correlated with the known densities of nAChR measured in vitro in human (r = 0.81) and rat brain (r = 0.90). CONCLUSION: These results demonstrate the feasibility of imaging nAChRs in vivo. Fluorine-18-FPH appears to be a suitable tracer to study nAChRs in the human brain.

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BACKGROUND: Patients may require perioperative cooling for a variety of reasons including treatment of a malignant hyperthermia crisis and induction of therapeutic hypothermia for neurosurgery. The authors compared heat transfer and core cooling rates with five cooling methods. METHODS: Six healthy volunteers were anesthetized with desflurane and nitrous oxide. The cooling methods were 1) circulating water (5 degrees C, full-length mattress and cover), 2) forced air (10 degrees C, full-length cover), 3) gastric lavage (500 ml iced water every 10 min), 4) bladder lavage (300 ml iced Ringer's solution every 10 min), and 5) ice-water immersion. Each method was applied for 40 min or until the volunteers' core temperatures approached 34 degrees C. The volunteers were rewarmed to normothermia between treatments. Core cooling rates were evaluated using linear regression. RESULTS: The first volunteer developed abdominal cramping and diarrhea after gastric lavage. Consequently, the technique was not again attempted. Bladder lavage increased heat loss approximately 10 W and decreased core temperature 0.8 +/- 0.3 degrees C/h (r2 = 0.99 +/- 0.002; means +/- SD). Forced-air and circulating-water cooling comparably increased heat flux, approximately 170 W. Consequently, core cooling rates were similar during the two treatments at 1.7 +/- 0.5 degrees C/h (r2 = 0.99 +/- 0.001) and 1.6 +/- 1.1 degrees C/h (r2 = 0.98 +/- 0.02), respectively. Immersion in an ice water slurry increased heat loss approximately 600-800 W and decreased core temperature 9.7 +/- 4.4 degrees C/h (r2 = 0.98 +/- 0.01). Immersion cooling was associated with an afterdrop of approximately 2 degrees C. CONCLUSIONS: Bladder lavage provided only trivial cooling and gastric lavage provoked complications. Forced-air and circulating-water cooling transferred relatively little heat but are noninvasive and easy to implement. Forced-air or circulating-water cooling, perhaps combined with intravenous administration of refrigerated fluids, may be sufficient in some patients. When noninvasive methods prove insufficient for rapid cooling, ice-water immersion or peritoneal lavage probably should be the next lines of defense.

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Recent studies evaluating perioperative cutaneous-to-core heat transfer indicate that: Thermoregulatory vasoconstriction prevents further core cooling in anesthetized subjects during mild cooling. Thermoregulatory vasoconstriction only slightly decreases core cooling rates in anesthetized subjects during vigorous cooling. Thermoregulatory vasoconstriction does not impair vigorous core rewarming during anesthesia. Vigorous postanesthetic cutaneous warming increases core temperature much faster than passive insulation. Under conditions of mild thermal stress, thermoregulatory vasoconstriction is thus able to protect core temperature by reducing cutaneous heat transfer and functionally isolating the peripheral and core thermal compartment. Consequently, anesthetic-induced alterations in vasomotor tone is one of the major factors influencing core temperature in patients who are not actively cooled or warmed. In contrast, thermoregulatory tone is insufficient to prevent core temperature perturbations in patients undergoing vigorous cutaneous cooling or warming.

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BACKGROUND: Although forced-air warming rapidly increases intraoperative core temperatures, it is reportedly ineffective postoperatively. A major difference between these two periods is that arteriovenous shunts are usually dilated during surgery, whereas vasoconstriction is uniform in hypothermic postoperative patients. Vasoconstriction may decrease efficacy of warming because its major physiologic purposes are to reduce cutaneous heat transfer and restrict heat transfer between the two thermal compartments. Accordingly, we tested the hypothesis that thermoregulatory vasoconstriction decreases cutaneous transfer of applied heat and restricts peripheral-to-core flow of heat, thereby delaying and reducing the increase in core temperature. METHODS: Eight healthy male volunteers anesthetized with propofol and isoflurane were studied. Volunteers were allowed to cool passively until core temperature reached 33 degrees C. On one randomly assigned day, the isoflurane concentration was reduced, to provoke thermoregulatory arteriovenous shunt vasoconstriction; on the other study day, a sufficient amount of isoflurane was administered to prevent vasoconstriction. On each day, forced-air warming was then applied for 2 h. Peripheral (arm and leg) tissue heat contents were determined from 19 intramuscular needle thermocouples, 10 skin temperatures, and "deep" foot temperature. Core (trunk and head) heat content was determined from core temperature, assuming a uniform compartmental distribution. Time-dependent changes in peripheral and core tissue heat contents were evaluated using linear regression. Differences between the vasoconstriction and vasodilation study days, and between the peripheral and core compartments, were evaluated using two-tailed, paired t tests. Data are presented as means +/-SD; P < 0.01 was considered statistically significant. RESULTS: Cutaneous heat transfer was similar during vasoconstriction and vasodilation. Forced-air warming increased peripheral tissue heat content comparably when the volunteers were vasodilated and vasoconstricted: 48 +/- 7 versus 53 +/- 10 kcal/h. Core compartment tissue heat content increased similarly when the volunteers were vasodilated and vasoconstricted: 51 +/- 8 versus 44 +/- 11 kcal/h. Combining the two study days, the increase in peripheral and core heat contents did not differ significantly: 51 +/- 8 versus 48 +/- 10 kcal/h, respectively. Core temperature increased at essentially the same rate when the volunteers remained vasodilated (1.3 degrees C/h) as when they were vasoconstricted (1.2 degrees C/h). CONCLUSIONS: The authors failed to confirm their hypothesis that thermoregulatory vasoconstriction decreases cutaneous transfer of applied heat and restricts peripheral-to-core flow of heat in anesthetized subjects. The reported difference between intraoperative and postoperative rewarming efficacy may result from nonthermoregulatory anesthetic-induced vasodilation.

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Perioperative thermal manipulations are usually directed at the skin surface because methods of directly warming the core are invasive or ineffective. However, inadequate heat flow between peripheral and core compartments will decrease the rate at which core temperature changes. We therefore determined whether core hypothermia is delayed after initiation of surface cooling. Six volunteers were anesthetized with propofol and midazolam, and maintained under three layers of passive insulation for 2.5-4 h. Subsequently, the skin surface was cooled using forced air, 1000 L/min, at 10 degrees C. Isoflurane was added as necessary to maintain arteriovenous shunt vasodilation. Overall heat balance was determined from the difference between cutaneous heat loss (thermal flux transducers) and metabolic heat production (oxygen consumption). Average arm and leg (peripheral) tissue temperatures were determined from 19 intramuscular needle thermocouples, 10 skin temperatures, and "deep" foot temperature. Overall body heat content decreased approximately 234 kcal during 2.5 h of active cooling. Core temperature, which was nearly constant before active cooling, decreased approximately 1.3 degrees C/h. There was no delay between initiation of active cooling and the decrease in core temperature. Furthermore, peripheral (arm and leg) and core (trunk and head) tissue heat contents decreased at virtually the same rates: approximately 50 kcal/h and approximately 47 kcal/h, respectively. These data indicate that there is little restriction of heat flow between peripheral and core tissues in vasodilated, anesthetized subjects.

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BACKGROUND: The purpose of this pilot study was to evaluate the impact of an 8-week cognitive-behavioral self-help educational program for individuals with COPD on level of disability. METHODS: Eight adults ranging in age from 58 to 83 years attended a program that included a cognitive-behavioral intervention strategy. Levels of disability, cognitive distortion, anxiety, depression, somatic symptoms, and hostility were measured pre- and posttreatment using the Sickness Impact Profile, two Cognitive Error Questionnaires and the Symptom Questionnaire. RESULTS: Significant decreases were found in the Psychosocial and Total Sickness Impact Profile Scores (p value = 0.02 and p value = 0.03, respectively). On the General-Cognitive Error Questionnaire, the personalization subscale decreased significantly (p value = 0.04). On the COPD-Cognitive Error Questionnaire, the selective abstraction subscale decreased significantly (p value = 0.02). CONCLUSION: Findings suggest a positive treatment response to the program.

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Heat transfer between the core and its environment in normothermic and slightly hypothermic situations is determined largely by the influence of vasomotion on convection. Tonic vasoconstriction, the normal barrier to heat loss from the core, is impaired upon induction of anesthesia. The resulting dilation of the arteriovenous shunts leads to redistribution of heat from the core to the periphery, diminishing the temperature gradient between the two compartments. With reemergence of thermoregulatory vasoconstriction at core temperatures near 34 degrees C, the core and the periphery are again separated, with metabolic heat being largely constrained to the core. Under normal conditions of mild thermal stress, thermoregulatory vasoconstriction is thus able to protect core temperature by reducing cutaneous heat transfer and functionally isolating the peripheral and core thermal compartments. Consequently, anesthetic-induced alterations in vasomotor tone is one of the major factors influencing core temperature in patients who are not actively cooled or warmed. In contrast, thermoregulatory tone is insufficient to prevent core temperature perturbations in patients undergoing vigorous cutaneous cooling or warming.

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The purpose of this research was twofold: to describe the types of drugs and alcohol abused by pregnant multisubstance abusers enrolled in a substance abuse and treatment programme, and to describe the types of changes in drug-taking behaviours during pregnancy. An exploratory study, including interviews and chart reviews, was conducted with 31 pregnant multisubstance abusers. Drug-taking behaviours, demographic factors of age, ethnicity, martial status, education, and pregnancy characteristics of gravida, living children, level of prenatal care and trimester of pregnancy were measured. Most of the women were in their Twenties, Hispanic, single and had some high school education. Most of the women were multiparas to grand multiparas, yet they had only one or two living children, and all were receiving prenatal care. Their self-reports were validated by urine screening. Generally, the women reported that they did change their drug-taking behaviours, and many women decreased their substance abuse.

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A descriptive survey was conducted with 31 pregnant women who were substance users enrolled in a perinatal treatment program. The purpose of the study was to determine the women's health behaviors by using open-ended questions. Most of the women were between 20 and 29 years of age, Hispanic, not married, unemployed, and had partial or completed high-school education. The women had multiple pregnancies with few living children. The majority of the women were 4 to 6 months pregnant and all had received prenatal care. The women made health behavior changes during pregnancy related to nutrition, substance use, self-care, exercise, lifestyle, and seeking counseling. Over 52% of the women reported they made these behavioral changes because they wanted a healthy baby.

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PROBLEM: To explore patterns and levels of self-esteem of pregnant substance abusers. METHODS: A descriptive prospective study to describe the self-esteem of pregnant substance abusers. Subjects (N = 31) were abusing and dependent on three or more legal and/or illegal substances. Subjects were asked one open-ended question regarding their self-esteem, then the Rosenberg Self-Esteem Inventory (RSI) was administered. FINDINGS: Subjects gave 46 responses to the open-ended question. Overall, they used a single word to describe self-esteem. The most frequent response on the RSI was "low" for self-esteem, 23 subjects used positive terms, 20 used negative terms, and 3 reported a neutral term. The RSI confirmed the aspects of low self-esteem. CONCLUSIONS & IMPLICATIONS FOR NURSING: Problems with low self-esteem were evident. Intervention strategies need to be developed to increase self-esteem in pregnant substance abusers.

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Global tissue damage due to oxygen-derived free radicals has been implicated in several pathological processes including exposure to ionizing radiation, and postischemic reperfusion of the heart or kidney. Recently pyruvate, a hydroperoxide scavenger, has been shown to protect against functional damage during postischemic reperfusion of the heart and in acute renal failure. In the present study, pyruvate was found to protect against inactivation of partially purified guinea pig renal and rat cardiac Na+,K(+)-ATPase which occurred when microsomal membranes were assayed for 1 hr at 37 degrees C (pH 7.5) in the presence of a free radical generating system (FRGS) containing 0.3 mM t-butylhydroperoxide and horseradish peroxidase. The presence of the FRG system inhibited the guinea pig renal Na+,K(+)-ATPase activity by 48.2 +/- 4.8% (N = 10, P < .05) and the presence of 0.2 to 20 mM pyruvate partially protected the Na+,K(+)-ATPase. At 5 mM pyruvate Na+,K(+)-ATPase was inhibited by only 18.8 +/- 2.5% (N = 10, P < .05) but increasing the pyruvate concentration gave no further protection. Equimolar concentrations of glucose, mannitol or lactate were without effect. The protection appeared to require an alpha-keto acid since alpha- but not beta-ketoglutarate was also effective and the mechanism is most probably the scavenging of t-BHO2. The results of the present study therefore support the hypothesis that, if free radical damage to native Na+,K(+)-ATPase does contribute to global tissue injury in certain pathological processes, pyruvate, in addition to being a powerful metabolic effector of recovery, may also protect against oxidative damage.

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We have studied the interaction of LDL and Lp[a] with fibroblasts. Our studies suggest that Lp[a] does not effectively compete with LDL for binding to the LDL receptor, and does not efficiently suppress the activity of the intracellular enzyme HMG-CoA reductase. However, Lp[a-], formed by reduction of the disulfide bond between apo[a] and apoB, behaves much like homologous LDL, whether or not apo[a] is removed from the mixture, and in spite of the fact that one or more apoB disulfides may also have been cleaved. In our studies we also noted that Lp[a] often enhanced binding of 125I-LDL by fibroblasts. Further investigation has suggested that this interaction is time-dependent. Experiments in receptor-negative fibroblasts indicate that the enhancement is not related to the presence of the LDL receptor; however, it is inhibited by the removal of calcium from the medium. The presence of sialic acid at millimolar concentrations in the medium inhibits much of the Lp[a]-enhanced binding of 125I-LDL to the cells. These studies suggest that Lp[] may in some way enhance LDL binding to cells, perhaps via interaction with cell surface glycosaminoglycans or proteoglycans or with collagen.

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BACKGROUND AND OBJECTIVES: Atraucan 26-gauge spinal needles have a tip designed to make a small linear cut (as opposed to a V-shaped cut) in the dura mater. The cut is shorter than the outside diameter of the needle and is dilated as the needle passes through the dura. The needle is used with a 20-gauge introducer. In vitro, it causes less leakage of cerebrospinal fluid than Quincke 26-gauge or Sprotte 24-gauge needles. This study was designed to test the ease of use and any damage caused to the needle tip during lumbar dural puncture. METHODS: This was a multicenter trial (six centers in five countries) involving 362 patients undergoing spinal anesthesia. A detailed questionnaire was filled in for every patient by the anesthesiologist. All the needles were returned to the factory and examined microscopically for damage. RESULTS: Lumbar dural puncture was successful in all but one patient. Spinal anesthesia was satisfactory for the planned surgery in 97%. Microscopy of the needle tips showed only a minor degree (0.01-0.19 mm) of bending in 14%, and none of the tips had a "hook." Postdural puncture headache (PDPH) occurred in nine patients (2.5%), all but one of whom (a 15-year-old male) were females under 55 years of age. CONCLUSIONS: The Atraucan needle is easy to use and has a high success rate in identifying the subarachnoid space. Lumbar dural puncture causes minimal damage to the tip. The incidence of PDPH is low, but a larger comparative study needs to be performed.

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We have previously reported that chronic hypertension develops consistently in Wistar rats with a 25% reduction in renal mass (RRM) following the induction of insulin dependent diabetes mellitus (IDDM) with streptozotocin (STZ, 65 mg/kg body weight, intravenously). In this study, we examined the role of the endogenous digitalis-like substance in the development of hypertension. Four groups of rats were studied: 1) 25% RRM rats with STZ-induced IDDM (25-DM), 2) normal rats with STZ-induced IDDM (2K-DM), 3) 25% RRM rats with vehicle treatment (25-V), and 4) normal rats with vehicle treatment (2K-V). In 25-DM rats, blood pressure progressively increased during the 3 weeks after STZ treatment and was associated with microalbuminuria, low plasma renin activity, and extracellular volume expansion. In contrast, the 2K-DM, 25-V, and 2K-V rats remained normotensive. Furthermore, the plasma and urine levels of digoxin-like immunoreactive factor (DIF), determined by digoxin radioimmunoassay (Baxter), were significantly higher in hypertensive 25-DM rats than in their controls. The same was the case for plasma digitalis-like substance (DLS), determined by exposing canine Na+,K(+)-ATPase to plasma fractions and observing the percent inhibition. Increased DIF and DLS in hypertensive 25-DM rats was associated with a significant decrease in Na+,K(+)-ATPase activity of microsomes prepared from the left and right ventricles, when compared with microsomes from normotensive 2K-DM animals. Microsomal 5'-nucleotidase, a plasma membrane marker, was unchanged. The DIF and DLS correlated significantly with each other and with myocardial Na+,K(+)-ATPase activity and mean blood pressure. These results suggest that increased endogenous digitalis-like substance, which inhibits cardiovascular muscle cell Na(+)-K(+)-pump activity, may be involved in the mechanism of hypertension associated with IDDM in 25% RRM rats.

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Hypertension is frequently associated with insulin-dependent diabetes mellitus, but the mechanism of the hypertension is unknown. An animal model of insulin-dependent diabetes mellitus hypertension could be helpful in determining the mechanism, but experimental insulin-dependent diabetes mellitus has been infrequently and irregularly associated with hypertension. In an attempt to develop a dependable model of insulin-dependent diabetes mellitus hypertension, we studied seven series of rats receiving either streptozotocin, surgical reduction of renal mass, or both. We found that superimposing streptozotocin 65 mg/kg body weight on 25% reduced renal mass regularly produced insulin-dependent diabetes mellitus and low-renin volume-expanded hypertension and that the animals remained healthy and hypertensive for as long as followed (13 weeks). Microalbuminuria correlated temporally with blood pressure. We used this dependable model to examine the role of endogenous digitalis-like substance in the development of hypertension in insulin-dependent diabetes mellitus. Plasma levels of digoxin-like immunoreactive factor (DIF), determined with a digoxin radioimmunoassay, were significantly higher in these hypertensive rats than in normotensive control rats (two-kidney diabetic rats, 25% reduced renal mass rats receiving vehicle for streptozotocin). This increase in plasma DIF was associated with a decrease in Na+, K(+)-ATPase activity in microsomes prepared from left or right ventricle. Microsomal 5'-nucleotidase, a plasma membrane marker, was unchanged. The plasma DIF level correlated inversely with myocardial Na+, K(+)-ATPase activity and positively with systolic blood pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

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The question explored in this study was: What is the effect of cognitive distortion and depression on disability in arthritis patients when stage of disease is controlled? Patients (N = 165) completed the Sickness Impact Profile, two Cognitive Error Questionnaires, and the Symptom Questionnaire, and were staged for severity of disease. Findings indicated a significant effect of distortion on disability in rheumatoid arthritis patients; however, this effect varied by stage. Distortion and depression best explained total disability in Stage II (R2 = .60 using general distortion; R2 = .58 using arthritis distortion). Future nursing interventions designed to decrease or prevent distortion might reduce disability as well as depression.

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We have previously reported that myocardial microsomal Na+,K(+)-ATPase activity, arterial wall ouabain-sensitive 86Rb uptake, and arterial smooth muscle cell membrane potentials are decreased and plasma Na(+)-K+ pump inhibitory activity is increased in rats during the fifth week of one-kidney, one-clip hypertension. We here report measurements of these four parameters and blood pressure following unclipping. A new series of rats with one-kidney, one-clip hypertension was prepared. Each animal was paired with a one-kidney, sham-clipped (nonconstricting clip) control rat. After 5 weeks, the clips were removed. In the hypertensive animals arterial pressure promptly (within 3 h) returned to normal and remained at the level for 7 observation days. On the third day following unclipping, all four parameters were not significantly different from those in the paired control animals. On the seventh day following unclipping, three of the four parameters were not significantly different from those in the paired control animals and arterial ouabain sensitive 86Rb uptake was slightly increased relative to the value in the control animals. These studies invite further inquiry into the possible role of plasma Na(+)-K+ pump inhibitory activity in the genesis and maintenance of the hypertension in this model.

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