Breast-feeding by a cyclosporine-treated mother.

BACKGROUND: Cyclosporine is known to be excreted in breast milk, but levels in infants are not known. Post-transplant breast-feeding has been contraindicated in mothers treated with calcineurin inhibitors such as cyclosporine. CASE: A 35-year-old woman exclusively breast-fed her infant during the first 10.5 months of life while she was being treated with cyclosporine. Cyclosporine measurements in infant and maternal blood and breast milk revealed a mean breast milk/maternal blood level ratio of 84%, but undetectable levels in the infant. The infant grew and developed normally. CONCLUSION: The infant of a cyclosporine-treated mother was breast-fed exclusively during the first 10.5 months of life and did not absorb a detectable amount of the drug. Fetal growth and development were normal.

Effect of sexual and physical abuse on symptom experiences in women with irritable bowel syndrome.

BACKGROUND: Irritable Bowel Syndrome (IBS) is a common chronic functional bowel disorder characterized by alterations in bowel patterns and abdominal pain. One factor that is conjectured to contribute to the onset of IBS is sexual and/or physical abuse in childhood or as an adult. This conjecture is supported by the increased prevalence of abuse experiences in persons with IBS when compared to healthy controls or those with organically-defined gastrointestinal (GI) disorders. OBJECTIVES: The purposes of the present study were to (a) compare the history of sexual and physical abuse in a sample of women with IBS to a sample of women without IBS and (b) to compare women with IBS who had sexual and physical abusive experiences to those who had not on GI symptoms, psychological distress, healthcare-seeking behavior, and physiological measures. METHODS: Data were collected from two samples of women (ages 18-40 years) with IBS and controls were recruited through community advertisements and letters from a health maintenance organization. Participants completed questionnaires (i.e., Sexual and Physical Abuse, Bowel Disease Questionnaire, Symptom Checklist-90-R) during an in-person interview and completed a symptom diary each night across one menstrual cycle. Cortisol and catecholamine levels were determined in morning urine samples on 6 days across the menstrual cycle. RESULTS: More women in the IBS group reported unwanted sexual contact during childhood relative to control women. Within the IBS group, minimal differences were found between those who had experienced abuse and those who had not. Women with IBS who had experienced abuse reported greater impact of GI symptoms on activity. CONCLUSIONS: The prevalence of a history of childhood sexual abuse experiences is elevated among women with IBS. However, within women with IBS, those with a history of abuse do not appear to be different from those with no history of abuse on GI symptoms, psychological symptoms, or physiological arousal indicators.

Channelopathies: potassium-related periodic paralyses and similar disorders.

Channelopathy is a term used to describe clinical problems caused by disorders of membrane ion channels. Included in this disease category are certain types of periodic paralyses, ataxia, myotonia, migraine headache, epilepsy, nephrolithiasis, and long QT syndrome. This article briefly summarizes membrane ion channel structure and function and details several relatively common channelopathies. In hyperkalemic periodic paralysis, mutant skeletal muscle sodium channels fail to close completely after an action potential. This evokes two apparently opposite symptoms: myotonia (caused by a small depolarization and repetitive excitation) or paralysis (caused by larger depolarization and inexcitability). In hypokalemic periodic paralysis, mutation affects the closing of skeletal muscle calcium channels, causing transient paresis or paralysis. The task of the advanced practice nurse is to recognize these disorders, institute appropriate prophylactic measures and treatments, monitor symptom progression, and avoid complications. Understanding of channelopathies is advancing rapidly. On the horizon are therapies tailored to counter specific membrane ion channel defects.

Evidence for autonomic nervous system imbalance in women with irritable bowel syndrome.

Autonomic nervous system function was assessed in women with and without irritable bowel syndrome using frequency domain measures of heart rate variability. Women were interviewed and placed into the irritable bowel syndrome (N = 25) group based on history of diagnosis and self-report of current gastrointestinal symptoms. Women in the control group denied a history of chronic gastrointestinal symptoms (N = 15). Women were followed for one menstrual cycle with a symptom diary, and during mid-luteal phase they wore a Holter 24-hr electrocardiograph monitor. Women with irritable bowel syndrome demonstrated significantly lower vagal tone as measured by the high frequency spectrum relative to control women. In addition, women with irritable bowel syndrome had a flattened 24-hr pattern of heart rate variability, with significantly lower levels of vagal tone during sleep. These results suggest that systemic sympathovagal balance may be shifted in a subset of women with irritable bowel syndrome.

The relationship between psychological distress and gastrointestinal symptoms in women with irritable bowel syndrome.

BACKGROUND: Individuals with irritable bowel syndrome (IBS) are reported to experience more symptoms compatible with psychopathologic disorders, abnormal personality traits, and psychological distress. Conversely, individuals with psychiatric disorders report higher levels of gastrointestinal (GI) symptoms compatible with IBS. Thus, psychological distress may contribute to GI symptoms in individuals with IBS. OBJECTIVES: To examine psychological distress in women with IBS, women with similar GI symptoms but not diagnosed (IBS nonpatients, IBS-NP), and asymptomatic Control women. METHODS: The women (N=97) were interviewed, completed questionnaires, and maintained daily diaries for 2 months. Across-women and within-woman analyses were used to calculate the results. RESULTS: The IBS and IBS-NP groups had a higher percentage of lifetime psychopathology and recalled psychological distress. At least 40% of the women in the IBS and IBS-NP groups had positive relationships between daily psychological distress and daily GI symptoms. CONCLUSIONS: Psychological distress is an important component of the IBS symptom experience and should be considered when treatment strategies are designed.

Estrogen suppresses gastric motility response to thyrotropin-releasing hormone and stress in awake rats.

Symptoms associated with gastric motility alteration vary with stress and ovarian hormone status, most notably in women with irritable bowel syndrome. This study examines combined effects, comparing gastric motility during administration of a stress-related neuropeptide thyrotropin-releasing hormone (TRH) and restraint stress in conscious rats of varied ovarian hormone status. Adult rats were ovariectomized and implanted with estrogen, progesterone, or vehicle-releasing pellets. After 21 days, intracerebroventricular (i.c.) cannula and gastric tension transducer were implanted. After 25-27 days, motility was recorded during neuropeptide injection (TRH/saline i.c.) or restraint stress. TRH induced increased motility in all groups; the response varied with hormone group, and was least and briefest in estrogen-treated rats. Motility during restraint varied with hormone group; it was diminished in estrogen-treated but not other groups. Ovarian hormone status (estrogen) modifies gut response to TRH and restraint stress.

Gastric emptying and gastric-intestinal transit in rats with varying ovarian hormone status.

Basal and stimulated gastric emptying and gastrointestinal (GI) transit in rats of varying ovarian hormone status were compared to define direct ovarian hormone effects on GI function. Thyrotropin-releasing hormone (TRH) was used to evoke vagal GI motility stimulation. Adult female Sprague-Dawley rats were anesthetized (equithesin), ovariectomized, and implanted with 28-day estrogen (E), progesterone, (P), E+P, or vehicle (V) pellets; males were also studied. On Day 26, fasted rats were anesthetized (urethane). Nonabsorbable 14C polyethylene glycol-4000 in saline was gavaged at t = 0. At t = 5 minutes, TRH or saline was administered intracisternally. At t = 30 or 60 minutes, the GI tract was removed, ligated, sectioned, and counted. Gastric emptying was expressed as 100% minus the ratio of gastric to total counts; GI transit was expressed as geometric center of radioactivity. In saline-treated rats, gastric emptying and GI transit at 60 minutes varied significantly among ovarian hormone-treated groups, with E lower and males elevated. TRH-significantly increased both variables at both times in all groups. Results are consistent with acceleration of upper GI function in the absence of E, possibly contributing to GI symptoms during menopause and late luteal phase.

Advancing nursing practice: acute care nurse practitioners meet challenges at and beyond the health care horizon.

Preparation of advanced practice nurses (APNs) with acute care skills relevant to today's health care environment is a challenge faced by nurse educators, care providers, professional organizations, and regulatory agencies. The acute care nurse practitioner (ACNP) is prepared to provide multidimensional, risk-appropriate management of medically vulnerable patients with serious illness in a variety of settings. ACNPs conduct comprehensive health assessments, order and interpret diagnostic tests, diagnose and manage health problems and disease-related symptoms, prescribe and evaluate drugs and treatments, and coordinate care during setting transitions. Working independently and collaboratively the ACNP enhances access to care and quality of care for patients and families through cost-effective, outcome-oriented practice. This article describes health care market factors fostering ACNP practice, ACNP practice domain, the University of Washington ACNP program, and collaborative contributions from educators, care providers, professional organizations, and regulatory groups needed to implement the role.

Interventions for irritable bowel syndrome: a nursing model.

Irritable Bowel Syndrome (IBS) is a common problem affecting a significant portion of the U.S. population. Nurses are involved directly in the planning and implementing of therapeutic interventions for this patient population. Using a Human Response Model, the authors of this article review intervention studies for IBS. This model provides a context for integration of Person (vulnerability) and Environment (risk) factors that may modify the patient's response to a given therapeutic regimen. Human responses are categorized as Physiological, Pathophysiological, and Behavioral/Experiential. Interdisciplinary therapeutic strategies include motility manipulations via pharmacological agents, dietary modifications, and self-care enhancement. Areas for nursing research are described.

Gastric motility in rats with varying ovarian hormone status.

Gastrointestinal (GI) symptoms suggestive of altered motility vary with menstrual cycle phase and menopause, but the effects of ovarian hormones on gastric motility have not been described. Basal and stimulated gastric motility were studied in male and female rats that were ovariectomized and implanted with continuous-release progesterone and/or estrogen pellets. Following 26 days of hormone treatment, rats were implanted with a gastric tension transducer. Contractile activity was recorded, then thyrotropin-releasing hormone (TRH) or saline was injected intracisternally and motility was monitored. An index was calculated based on frequency and amplitude; response to TRH was expressed as percentage of the basal index. Basal contraction frequency was highest in the estrogen and estrogen+progesterone groups. Hormone treatment significantly affected the TRH-stimulated motility index; TRH induced increased motility in all groups, with larger, more sustained responses in vehicle, progesterone, and male groups. Results demonstrate the ovarian hormone modulation of basal and stimulated gastric motility. Such modulation may contribute to changes in GI symptoms with altering ovarian hormone state.

Shivering following cardiac surgery: predictive factors, consequences, and characteristics.

BACKGROUND: Shivering is common after cardiac surgery and may evoke harmful hemodynamic changes. Neither those changes nor factors increasing probability of shivering are well defined. OBJECTIVES: (1) To identify factors linked with risk of shivering by comparing age, weight, body surface area, gender, intraoperative details, anesthetics, postoperative temperatures, hemodynamics, and therapeutics in shivering vs nonshivering patients. (2) To describe temperatures, hemodynamics, therapeutics, myocardial oxygen consumption correlates (rate-pressure product, heart rate, systemic vascular resistance) in shivering and nonshivering groups, and shivering and nonshivering periods. (3) To characterize the electromyogram to determine whether the tremor is cold-induced. METHODS: A descriptive design with a time series component was used to study a convenience sample of 10 shivering and 10 nonshivering adults for 4 hours during early recovery from cardiac surgery. Pulmonary artery and skin (facial, calf, trunk) temperature were measured every 60 seconds; heart rate and arterial pressure, every 15 minutes; cardiac output, 3 times. Electromyogram was recorded intermittently. Medications and treatments were noted. RESULTS: Lower skin temperature was significantly related to shivering risk. Heart rate was significantly higher initially in shiverers and remained higher by 13.6 beats per minute. Significantly more nitroprusside was used to control arterial pressure before than after shivering. No significant differences were noted between groups in core temperature, age, weight, body surface area, anesthesia type, intraoperative temperature; or surgery, circulatory bypass, or cardiac cross-clamp duration. The electromyogram pattern during shivering was typical of that produced by cold. CONCLUSIONS: These results suggest that true shivering occurs after cardiac surgery. Skin, but not core, temperature and elevated heart rate predict shivering. Shivering may be more likely in hemodynamically unstable patients.

Comparison of diet composition in women with and without functional bowel disorder.

Nurses are often involved in helping patients alleviate chronic distressing gastrointestinal symptoms such as those associated with irritable bowel syndrome or functional bowel disorder. One therapeutic strategy is to increase dietary fiber intake and to eliminate gastrointestinal (GI) irritants such as caffeine, alcohol, and tobacco smoking. However, little work has been done to establish a relationship between dietary factors and chronic GI symptoms. In this article, the authors: (a) describe and compare caloric and dietary constituent intake in symptomatic (n = 18) and asymptomatic (n = 37) women, and (b) examine the relationships among diet, GI symptoms, and stool characteristics in the two groups. In particular, total calories, fiber, fat, protein, and carbohydrates as well as alcohol and caffeine intakes were compared in women who do not smoke. Because menstrual cycle phase modulates both symptoms and appetite, women were studied during the follicular phase. Groups had similar caloric, fat, and protein intakes. Fiber intakes were similar and similar to national norms in both groups. When compared with asymptomatic women, the symptomatic women consumed more refined carbohydrates. Relationships were observed among dietary intake of refined carbohydrates, fiber, GI symptoms, and stool characteristics in women with functional bowel disorder.

Intestinal transit and body weight responses to ovarian hormones and dietary fiber in rats.

A two-part experimental design was used to study the effects of ovarian hormone cessation, hormone supplementation, and dietary fiber composition on body weight, appetite, and intestinal transit. In Part 1, effects of ovarian hormone status on body weight and baseline and stimulated intestinal transit were measured in chow-fed rats. Sprague-Dawley rats were ovariectomized (OVX), then injected daily (22 days) with estrogen (E), progesterone (P), the combination (E + P), or placebo. Controls were sham operated and placebo injected. Among OVX rats, E and E + P had the least body weight gain (9%, 6%); placebo and P had the greatest (36%, 34%). In OVX-P, baseline intestinal transit (measured in anesthetized rats as distance traveled by a charcoal marker) was relatively low, but vagal stimulation via centrally administered thyrotropin-releasing hormone evoked an increase significantly larger than that in other groups. In Part 2, experiments probed the interacting effects of ovarian hormone cessation and dietary fiber composition on body weight and baseline intestinal transit. Caloric intake was measured to determine the contribution of altered appetite. Rats were OVX or sham operated, then fed liquid diets with or without dietary fiber (25 days). OVX fiber-fed rats had significantly higher caloric intake, weight gain, and baseline intestinal transit than other groups. Caloric intake did not fully account for group differences. These results demonstrate modulation of GI function by ovarian hormones and dietary fiber.

Insulin-induced membrane changes in K(+)-depleted rat skeletal muscle.

Insulin-induced membrane changes were investigated in K(+)-depleted rat muscle. Male Sprague-Dawley rats were placed on a K(+)-free but otherwise adequate diet for 5-8 wk; serum K+ concentration ([K+]) dropped to 1.2-3.2 mM. Omohyoid membrane potential was -81 mV in 5.5 mM [K+] (SO4(2-)). Exposure to either insulin or low (0.5 mM) [K+] singly changed potential only slightly. The combination resulted in depolarization of 90% of fibers (-43 mV) and hyperpolarization of 10% of fibers (-101 mV). Fibers from normokalemic rats did not depolarize. Tetrodotoxin (TTX) blocked depolarization, implying the presence of noninactivating TTX-sensitive Na+ channels. K+ currents were measured using the three-electrode voltage clamp; movement of other ions was prevented by ion substitution, channel blockers, and depolarization-induced channel inactivation. K+ conductance was similar in control fibers with or without insulin. In the absence of insulin, currents in K(+)-depleted fibers were offset by a large leakage current that was significantly diminished when insulin was present. The insulin-induced current decrease was observed in nitrendipine, suggesting that the apparent decreased outward current was not an inward current carried by Ca2+. Data are consistent with altered Na+ and K+ channels in K(+)-depleted muscle, i.e., insulin-related closing of K+ channels initiates depolarization, which is then sustained by opening of noninactivating Na+ channels.

Mediation of thyrotropin-releasing hormone induced gastric motility increases in developing rats.

Centrally administered thyrotropin-releasing hormone (TRH) induces vagally mediated gastrointestinal effects which may be cholinergic, serotonergic or a combination. This study investigated mediation of TRH-stimulated gastric motility in developing rats. A serotonin (5-HT) antagonist (5-HT2, ketanserin or xylamidine; 5-HT3, MDL 72222) or an acetylcholine receptor blocker (atropine) was administered intraperitoneally 30 min prior to intracisternal TRH (5-10 micrograms). The 5-HT-depleting para-chlorophenylalanine (p-CPA) was administered 48 or 72 h prior to TRH. Gastric motility, monitored via extraluminal strain gauge, was not increased with TRH in atropine-pretreated rats. MDL 72222 had a significant age-related effect on TRH-induced gastric motility increases while 5-HT2 antagonists and p-CPA treatment did not. Thus, acetylcholine receptor blockade inhibits TRH-stimulated gastric motility in young and adult rats while 5-HT3 antagonism eliminates the motility response in young (7 and 10 days) rats.

A possible 5-HT3 component of thyrotropin-releasing hormone-induced increases in gastric motility in developing rats.

Intracisternal injection of thyrotropin-releasing hormone (TRH) increases gastric motility primarily via a vagal cholinergic mechanism. However, a serotonergic (5-HT) component may also exist. Rats (7, 10, 14, and > or = 50 days of age) were anesthetized and gastric motility monitored via an extraluminal strain gauge. Following baseline, ICS 205-930 which blocks 5-HT3 and 5-HT4 receptors (0.01, 0.10, or 1.0 mg/kg) was administered intraperitoneally, then 30 min later intracisternal TRH (5 or 10 micrograms). ICS 205-930 0.1 and 1.0 mg/kg blocked TRH-induced motility in 7-day-old rats. Results support a 5-HT3 or 5-HT4 receptor contribution to TRH-induced gastric motility stimulation, and suggest that receptor expression is dynamic during development.

Morphine inhibits TRH-induced gastric contractile activity.

This study investigated the effect of centrally and peripherally administered thyrotropin releasing hormone (TRH) on gastric contractile activity of rats 14, 21, 28 and adult (greater than or equal to 50) days (D) of age, and the effect of morphine pretreatment on that response. Rats were anesthetized with urethane, then a tension transducer was implanted on the anterior gastric corpus. Following baseline recording, rats were pretreated with intraperitoneal morphine (2 mg/kg). TRH (5 micrograms) in saline or saline alone (0.6 microliters) was then injected into the cisternum magnum. Additionally, dose response to TRH was examined in 14- and 50-day-old rats. Intracisternal TRH induced a dose-related increase in gastric contractile activity in both 14- and 50-day-old rats. Higher doses of TRH (10 and 30 micrograms) prolonged the response as compared to low doses. Peripheral morphine pretreatment blocked the TRH-induced increase in gastric contractile activity in all age groups although a higher morphine dose (10 mg/kg) was needed to block the effect in 28D rats. Intravenous TRH (5, 10, 30 micrograms) produced an increase in gastric contractile activity in 14D rats which was blocked by vagotomy.

GI symptoms, function, and psychophysiological arousal in dysmenorrheic women.

In a previous study, gastrointestinal (GI) symptoms and stool characteristics were found to be influenced by menstrual cycle phase. The current study was designed to replicate initial work regarding GI symptoms and stool characteristics and to explore the relationships between GI symptoms, stool characteristics, ovarian hormone levels, and indicators of psychophysiological arousal. Fifty women (dysmenorrheic, N = 22; nondysmenorrheic, N = 28) maintained a daily dairy for recording stool characteristics, GI symptoms, and daily anxiety level. First morning void urine specimens for catecholamine assays and serum samples for ovarian hormone and cortisol determinations were obtained at menses, follicular, and luteal phases. Results showed menstrual cycle-related differences in stool characteristics and report of GI symptoms, with the greatest changes occurring at menses in the total sample. Dysmenorrheic women reported higher levels of all GI symptoms at menses as compared to nondysmenorrheic women. In addition, cycle-related differences in serum cortisol, urine catecholamines, and report of anxiety were also noted, particularly in dysmenorrheic women. However, looser stools and GI symptoms at menses were not correlated with absolute levels of ovarian hormones or indicators of psychophysiological arousal.