Do drug costs affect physicians' prescription decisions?

OBJECTIVE

To study the impact of the cost of pharmaceuticals on physicians' decisions about drug prescription.

DESIGN

A simulation protocol for the treatment of two patients, one with mild and the other with a severe form of urinary tract infection (UTI), was designed. Thirty family physicians in outpatient clinics and 30 physicians in the internal medicine wards of a Community Hospital participated in the project. They had to prescribe treatment for the patients twice: at phase I, when the drug cost was unknown, and at phase II, after 2 months, when the price of the drugs was brought to their attention. The physicians selected the medication from a list of drugs commonly used for the treatment of UTIs.

RESULTS

Analysis of the findings indicates that an awareness of drug costs affects prescription decisions among physicians in hospital wards, whereas family physicians showed a preference for less expensive drugs even before they were informed about drug costs. An extrapolation of the results shows that knowledge about the cost of the drugs usually administered for treatment of UTI, could save at least IS 112,883 ($34,207) a month to Kupat Holim Klalit (KHK) the health insurance institution to which the outpatient clinics and the hospital belong.

CONCLUSIONS

When economic aspects of healthcare are considered, information on drug costs may be an important factor in physicians' decision-making processes and for saving pharmaceutical expenses.

Candida (Torulopsis glabrata) liver abscesses eight years after orthotopic liver transplantation

The authors report the case of a 48-year-old man in whom candida (Torulopsis glabrata) liver abscesses developed 8 years after liver transplantation. After a week of fever, computed tomography and Doppler ultrasonography showed several fluid-filled loculations in the left lobe of the liver and hepatic arterial stenosis. Aspirates from the abscesses contained T. glabrata organisms. This complication probably developed because hepatic arterial stenosis resulted in bile infarcts (bilomas), which were contaminated via the biliary tract with candida from the biliary-enteric anastomosis. Catheter drainage and administration of amphotericin B for 10 weeks permitted successful retransplantation. T. glabrata liver abscesses, a life threatening complication that can occur long after liver transplantation, can be successfully managed by aggressive medical treatment followed by retransplantation.

Phantom visions: real enough to touch

Blind and partially sighted people are in danger of being wrongly treated for mental health problems. Jane Hart explains the phenomenon known as Charles Bonnet Syndrome.

Alveolar fluid glutathione is not reduced in asymptomatic HIV-seropositive subjects

Glutathione is an important antioxidant tripeptide that is found in high concentrations in the epithelial lining fluid (ELF) of the lung. Previous investigators demonstrated a deficiency of glutathione (GSH) in the epithelial lining fluid of human immunodeficiency virus (HIV)-seropositive patients. The current investigation performed bronchoalveolar lavage (BAL) on 59 asymptomatic HIV-seropositive subjects (mean CD4: 365.9 +/- 31.2 cells/mm3) and 12 normal control subjects. The volume of ELF and the concentration of glutathione and oxidized glutathione were determined. The concentration of total GSH in ELF was not significantly different in HIV-seropositive individuals compared with normal subjects (628.1 +/- 63.9 microM versus 499.9 +/- 86.0 microM, p = 0.38). However, there was a significantly higher concentration of ELF GSH in HIV-seropositive cigarette smokers (n = 30) compared with nonsmokers (n = 29) (800.3 +/- 107.7 microM versus 443.6 +/- 45.3 microM, p = 0.004). The percentage of total GSH in the oxidized form (GSSG) was similar in both the HIV-seropositive and the normal subject groups (3.4 +/- 0.3% versus 3.0 +/- 0.4%, p = 0.559). There were no significant correlations between ELF GSH or GSSG concentrations and age, CD4 count, or pulmonary function. There was, however, a significant negative correlation between BAL lymphocyte percentage and GSH. The current study suggests that for those patients whose HIV infection is at a relatively early phase, the levels of GSH in the lung ELF are normal.

Plasma fibrinogen in Israeli Moslem and Jewish school-children: distribution and relation to other cardiovascular risk factors. The Petah Tikva project

Plasma fibrinogen levels were measured in 1,175 Israeli schoolchildren, aged 9-18 years, originating from diverse ethnic groups. The Moslem children displayed striking differences in levels and age-patterns of fibrinogen compared to Jewish children. Lower mean plasma fibrinogen levels in boys aged 9-10, 13-14 and 16-18 were observed among Moslem boys, compared to their Jewish counterparts born in Israel. Moslem girls showed lower levels of fibrinogen than Jewish Israeli girls at ages 9-10 and 16-18. While the Jewish children displayed an age-associated fibrinogen pattern comparable at the three age groups, the levels for Moslem children increased pre-puberty and decreased post-puberty, peaking at 13-14 years. No significant difference in mean plasma fibrinogen was found between sexes within ethnic groups. A number of statistically significant but low correlations (-0.32 to 0.24) were found between plasma fibrinogen and high density lipoprotein cholesterol (HDL-C) as a percentage of total cholesterol, triglycerides, blood glucose, uric acid, blood pressure, Quetelet index and sports activity. The difference between fibrinogen levels might point to a possible ethnicity risk factor explanation rather than environmentally acquired factors.

Patient satisfaction in two departments of surgery in a community hospital

Patient satisfaction with medical and nursing care was evaluated in two surgical departments of a community teaching hospital in Petah Tikva (now called Rabin Medical Center, Golda Campus). The interview, conducted before the patients were discharged, related to their perception of the preoperative period, the attitude of the personnel in the operating room before anesthesia was administered, and their satisfaction during the postoperative period. The questionnaire completed by the interviewer included questions on the time that elapsed from admission to the first examination by a physician and a nurse, whether the patient received information about the operation and its possible complications, was examined by the anesthetists, received details regarding the results of the surgical procedure, and what his or her impression was of the attitude of the nursing staff. The patients were asked to rate their evaluation on a scale from 1 to 10. The results showed high satisfaction with the services provided and were similar for both departments. The small number of patients whose satisfaction rated from 5 to 8 complained about the sanitary conditions in the toilets, the overcrowded departments, and the lack of sufficient number of registered nurses during the night shifts.

Complete lymphoid chimerism and chronic graft-versus-host disease in an infant recipient of a hepatic allograft from an HLA-homozygous parental living donor

Living-related donor liver transplantation (LDLT) is an accepted approach to pediatric liver transplantation. Parental donation imposes a significant risk of chimerism with graft-versus-host disease (GVHD) because donors homozygous at all HLA loci (1.6% of the population) present no mismatched HLA antigens to be recognized by their offspring's immune system. The case of a 9-month-old who underwent LDLT with her 23-year-old HLA-homozygous mother as a donor demonstrates the consequences of this occurrence. The patient developed GVHD with aplastic anemia; the patient's nucleated peripheral blood elements were shown to be entirely derived from the donor. Later, after some marrow recovery, the patient's circulating lymphocytes had a donor origin, while the marrow-derived neutrophils had a recipient origin. The patient suffers from chronic GVHD and debilitating skin disease several years posttransplant. Our current protocol calls for HLA typing to eliminate parents who are homozygous at all HLA loci as donors of hepatic allografts to their children.

Estimation of vitamin needs--riboflavin, vitamin B6 and ascorbic acid-according to blood parameters and functional-cognitive and emotional indices in a selected well-established group of elderly in a home for the aged in Israel

OBJECTIVE

To evaluate the vitamin status and the effects of micronutrient supplementation as determined by biochemical assays and functional, cognitive and emotional tests in a selected well-established group of elderly people, average age above 80 years.

METHODS

Dietary consumption was evaluated by in-person interview using a food frequency questionnaire. Medical, biochemical, nutritional, functional, cognitive and behavioral parameters were assessed in elderly subjects (n = 12) living in a home for the aged, at baseline and after 42 days of micronutrient supplementation. The same parameters were assessed in additional subjects (n = 9), at baseline only.

RESULTS

In all subjects, most of the micronutrients were not supplied at an adequate level. Supplementation of micronutrients at a level of 100% RDA improved parameters related to vitamin status, the activation coefficients (AC) of GR (glutathione reductase) and AST, blood ascorbic acid concentrations, functional-cognitive evaluation values, blood pressure, pulse rate, and serum cholesterol and triglycerides levels. At baseline, the following parameters significantly correlated with vitamin intake and were used for the estimation of vitamin needs: AC of GR, Tinetti Balance Evaluation, FIM and recorded morbidity.

CONCLUSIONS

On the basis of limited available data, calculation of vitamin needs based on regression lines resulted in estimates (mg/day) of: > 150 for ascorbic acid, > 3 for riboflavin, > 3 for vitamin B6. Expanding the current practice of supplementing micronutrients at a level of 100% RDA (in tablet form) that already exists in some elderly societies should be considered after a comprehensive study in a large group of elderly people.

Birth trauma. A five-year review of incidence and associated perinatal factors

OBJECTIVE

To determine the current incidence of clavicular fracture (CF), facial nerve injury (FNI) and brachial plexus injury (BPI) and identify the existence, if any, of associated perinatal factors with each injury.

STUDY DESIGN

A case-controlled study design was selected and the study conducted for births between January 1, 1985 and January 1, 1990, at Christ Hospital and Medical Center, a tertiary care center with level III perinatal services in suburban Chicago. Among a population of 19,370 consecutive deliveries, we identified the occurrences of CP, FNI and BPI by database search, and maternal and neonatal chart reviews. A control group was randomly selected. Maternal, labor, delivery and neonatal variables were then compared between the birth trauma and control groups for each specific injury.

RESULTS

The incidence per 1,000 live births and per 1,000 live-born cephalic singletons delivered vaginally for CF was 4.5 and 5.7; for FNI, 0.6 and 0.7; and for BPI, 0.9 and 1.1, respectively. To varying degrees, the data demonstrate that the occurrences of these injuries are associated significantly more often with prolonged gestation, epidural anesthesia, prolonged second stage of labor, oxytocin use, forceps delivery, shoulder dystocia, macrosomia, low Apgar scores and a previous maternal obstetric history of macrosomia when compared to controls. Other significantly associated variables include the presence of meconium in labor and neonatal hyperbilirubinemia. Despite the presence of multiple perinatal factors that are individually associated statistically with the injured groups, multiple logistic regression analysis predicted 44.2% of CF's, none of the FNIs and only 19% of the BPIs.

CONCLUSION

While multiple perinatal variables are statistically associated with the specific birth injuries studied, the use of multiple logistic regression analysis shows that the ability to predict these injuries is markedly limited.

Macronutrient consumption and nutritional status in a selected well-established group of elderly people in a home for the aged in Israel

OBJECTIVE

To evaluate the distribution pattern of the main macronutrients (protein, fat, carbohydrates) and fiber in a selected well-established group of elderly people, average age above 80 years.

METHOD

Dietary consumption was evaluated in a well-established group of 21 elderly people in a home for the aged by in-person interview using a food frequency questionnaire.

RESULTS

Daily energy intake was 1.87 Mcal (7.8 MJ) or 29.3 kcal/kg body weight, a value which lies within the range of 1.6 to 2.0 Mcal or 25 to 30 kcal/kg, found in 12 other studies conducted on elderly people. The average percentage of energy derived from macronutrients (with an individual range) was: protein 17.5 (13-22); fat 32.9 (25-44); and carbohydrates 49.6 (35-61). Fiber intake was 8.6 g/Mcal, lower than that found in three other studies. Positive coefficients of correlation were found between protein intake and the following parameters: serum urea (r = 0.28), cholesterol (r = 0.48) and DBP (r = 0.43).

CONCLUSIONS

In our small group of elderly, energy derived from protein was higher than that in most of other studies reviewed, and that from fat was higher than in half of those studies. These values were remarkably higher than the suggested values. Energy derived from carbohydrates was close to that found in other studies. Monitoring of dietary macronutrients might improve the nutritional and the physiological status of the elderly.

Posttransplant lymphoproliferative disease in pediatric liver transplantation. Interplay between primary Epstein-Barr virus infection and immunosuppression

The incidence, risk factors, and outcome of posttransplant lymphoproliferative disease (PTLD) were examined for 298 children undergoing liver transplantation. The overall incidence of PTLD was 8.4% (25 of 298). Intensity of immunosuppression was found to be a major risk factor for the development of PTLD. Cyclosporine and tacrolimus when used as primary immunosuppression were associated with the development of PTLD in 4.3% and 6.6% of cases (P=NS). OKT3 and tacrolimus, when used as rescue therapy for steroid-resistant rejection, were associated with a comparable increase in the risk of developing PTLD (10.9% and 11.1%, P=NS). Patients requiring both OKT3 and tacrolimus to treat refractory rejection were at significantly increased risk for PTLD (28.1% vs. 4.3% or 6.6%, P<0.0001). PTLD was more common in patients who received transplants for Langerhans cell histiocytosis relative to other indications for transplantation (66% vs. 8.4%, P=0.0005). The data also support an association between primary Epstein-Barr virus (EBV) infections following transplantation and the development of PTLD. While only three patients were EBV seropositive before transplantation (14%), 19 patients were EBV seropositive at the time of diagnosis of PTLD (90%), confirming a high incidence of primary EBV infections in patients with PTLD (21 patients had both pre- and posttransplant EBV serologies). In this series, PTLD was associated with a mortality rate of 60%, and 12 of the 15 patients who died had persistent tumor at the time of death. Five of the 13 patients rendered disease-free developed ductopenic rejection. Of the four with severe liver dysfunction, two have undergone successful retransplantation and are alive without evidence of PTLD. In conclusion, intense immunosuppression using OKT3 and tacrolimus as rescue agents was associated with a significant increase in the incidence of PTLD. Primary EBV infection after transplantation further accentuated this risk. Independent of these risk factors, patients with Langerhans cell histiocytosis were at significantly increased risk for PTLD. The identification of high-risk patients should allow the development of protocols to screen patients for primary EBV infections and early indications of PTLD, as well as the institution of preemptive antiviral and antitumor therapies.

Vincristine-induced alterations in Schwann cells of mouse peripheral nerve

The sciatic nerve of C57Bl mice was examined with a transmission electron microscope to study the ultrastructural alterations in Schwann cells following treatment with escalating doses of vincristine. Results indicated that the drug exerts a dose-related effect. Total doses up to 8 micrograms/mouse did not cause any visible damage to Schwann cells. Higher doses induced not only damage to individual cells, but also affected a greater percentage of them. The myelin sheath was the most affected organelle. Schwann cells of myelinated fibers showed greater damage than those of unmyelinated fibers.

Effect of high doses of 2-CdA on Schwann cells of mouse peripheral nerve

The present study was undertaken to examine the effect of 2-CdA (Leustatin) on the Schwann cells of myelinated and unmyelinated fibers of peripheral mouse nerve. Two groups of mice were injected intravenously for seven days with 2-CdA: one group received daily doses of 1 mg/kg and the other 0.5 mg/kg. Both doses exceeded those accepted in clinical practice. Mice injected with saline served as controls. The sciatic nerve was then dissected and examined with a transmission electron microscope. The Schwann cells of both the myelinated and unmyelinated nerve fibers of the animals receiving the higher doses of 2-CdA showed nuclear and nucleolus damage, loss of heterochromatin, vacuolization and disorganization of the myelin sheaths. The mesaxons and the axons were also damaged. The Schwann cells of the animals treated with the lower doses appeared undamaged. The results indicate that in contrast to other anticancer drugs known to produce peripheral neuropathy, 2-CdA may cause damage to the Schwann cells only at doses exceeding the therapeutic ones.

Survey of patient satisfaction in a community hospital

To assess the satisfaction with the department and hospital services provided by a medium-size community hospital during a 2 month period (April-May 1995), 118 randomly chosen patients were asked to complete a questionnaire designed to reflect their opinions during hospitalization. The principal points of the survey concerned the general perception regarding the services in the department and the hospital, the admission and discharge procedures, the quality of food and sanitary conditions, an evaluation of the physicians' and nurses' skill and attitude, as well as their compliance to patients' needs. Overall satisfaction with the medical care was very high, the physicians' attitude and nurses' compliance being the two most important determinants. The role of this type of questionnaire as an instrument for improving health services is emphasized.

Ploidy as a prognostic feature in colonic adenocarcinoma

OBJECTIVE

To determine whether DNA content and cell-cycle kinetic characteristics in Dukes stage B colonic adenocarcinomas provide additional prognostic information in the context of clinicopathologic variables of known significance.

DESIGN

Archival, paraffin-embedded tissue blocks from 210 Dukes B colonic adenocarcinomas were retrieved. After confirming stage, tumor cell nuclei were extracted, suspended, and stained. Cell nuclei from adjacent normal colon mucosa were used as controls.

SETTING

University-based, tertiary cancer referral center.

INTERVENTIONS

Samples obtained from tumors resected at our institution between 1965 and 1984 were analyzed by flow cytometry for DNA index (DI) and percentages of cells in synthesis (S) phase (%S) and in G2 and mitosis (M) phases (%G2M). The data were correlated with 5-year survival. Follow-up was complete in all patients to at least 5 years.

RESULTS

Univariate analysis showed that the highest survival rates were associated with DI values near 1 and 2 (diploid and tetraploid tumors, P = .02) and the lowest %G2M values (tumors with fewer mitoses; P = .01). Five-year survival rates also differed significantly between patients with diploid (DI < 1.1) and those with aneuploid (1.1 < DI < 2) tumors (80% vs 64%, respectively; P = .02). Multivariate analysis revealed that race (P < .01), lymphatic or capillary microinvasion (P < .03), and ploidy (P < .05) were significantly associated with outcome. The influence of ploidy, race, and microinvasion on 5-year survival was estimated with logistic regression, and 8 subgroups of patients emerged with 5-year survival probabilities ranging from 39% for black patients with aneuploid tumors and microinvasion to 88% for white patients with diploid tumors and no microinvasion.

CONCLUSIONS

Tumor DNA content provides additional independent information that allows further refinement of our prognostic ability in patients with Dukes B colonic adenocarcinoma. This may aid in the identification of a cohort of patients who may potentially benefit from aggressive adjuvant therapy.

Tacrolimus for primary treatment of steroid-resistant hepatic allograft rejection

Twelve patients who experienced steroid-resistant rejection after primary liver transplantation while receiving cyclosporine-based therapy were converted to tacrolimus without receiving OKT3 or additional steroids. The indications for conversion were ongoing biopsy-confirmed rejection. All patients had received one course of high-dose intravenous steroids, which failed to reverse the rejection episode. No other antirejection therapy was given. Tacrolimus was initiated to reverse rejection and for maintenance therapy. The tacrolimus target level was 15-20 ng/ml (whole blood, IMX). All 12 patients had rapid reversal of the rejection episode and did not experience recurrent rejection (mean follow-up: 8.2 +/- 1.2 months). The mean bilirubin level dropped from 6.1 mg/dl at the initiation of tacrolimus therapy to 4.4 mg/dl by day 7 of therapy, 2.5 mg/dl by day 14, and 1.5 mg/dl by day 21 (P < 0.003). Serum glutamic pyruvic transaminase demonstrated a similar response. The serum creatinine level was unchanged at 1.5 mg/dl. No major adverse reactions were noted in this group of patients. Patient and graft survival rates were 100%. Four of the eight patients with a follow-up of >4 months are no longer receiving steroid therapy. Tacrolimus is effective as the primary therapy for the treatment of steroid-resistant rejection and provides a rapid and sustained biochemical response. Patients with mild to moderate rejection may be safely converted from cyclosporine to tacrolimus without an additional steroid bolus or OKT3 therapy. Early "preemptive" conversion to tacrolimus prior to the use of additional steroids or OKT3 may decrease overall rejection therapy requirements. This approach has promise for improved graft survival and fewer infectious and immunologic complications.

Cognitive effects of resecting basal temporal language areas

Electrical stimulation of the basal temporal region of the dominant hemisphere before partial temporal lobectomy for epilepsy sometimes produces temporary interruption of language function, but the significance of removal of this area is unknown. We evaluated the correlation between resection of the basal temporal language areas (BTLA) and certain types of postoperative language deficits. In a population of 25 patients, we mapped the inferolateral temporal lobe with cortical electrical stimulation, verifying the positions of the stimulating electrodes with three-dimensional computed tomography (CT). Eighty percent of the patients developed transient language deficits with stimulation, particularly with tests of confrontation naming and comprehension. BTLA was primarily located in the fusiform gyrus, from 1 to 9 cm from the temporal tip. At testing 6-12 months after operation, patients with BTLA resection performed worse (mean 9% decrease) than those with no BTLA resection (mean 4% improvement) on tests of confrontation naming (p = 0.03). Resection size accounted for less of the variance in decrease in confrontation naming than did resection of the BTLA. Tests of performance I.Q. (PIQ), verbal I.Q. (VIQ), or recognition memory for word and verbal learning showed no significant difference between these groups. Most patients do not have language decrease with removal of basal temporal lobe 5-6 cm from the tip, even with removal of BTLA. Some patients, however, have persistent decrease in naming.

Effect of oral chemotherapy on the mitochondrial size of mouse intestinal cells

Since orally given cytotoxic agents may cause intestinal disfunction, the effect of oral administration of three cytotoxics, i.e., methotrexate (MTX), cyclophosphamide (CPA), and ftoral, a derivative of 5-fluorouracil (5-FU), on the gastric, liver, and small-intestine cells of C57B1 mice was studied by transmission electron microscopy. Although no ultrastructural alterations could be detected in the cells of the first two organs, the epithelial cells of the small intestine showed a marked increase in size of their mitochondria. In the control animals the mitochondrial size was in the range of 0.04-1.8 micron (mean +/- SE 0.54 +/- 0.01 micron). In the treated animals the size of the mitochondria ranged between 0.15 and 4.33 micron (mean +/- SE 0.73 micron) for those treated with MTX, 0.24-2.88 micron (mean +/- SE 0.80 +/- 0.02 micron) for those given CPA, and 0.28-5.3 micron (mean +/- SE 1.18 +/- 0.48 micron) for those treated with 5-FU. These findings were significantly different from those obtained in controls (P < 0.0001). In addition, in animals treated with MTX the mitochondria of the jejunal cells were surrounded by channels of rough endoplasmic reticulum. The cytoplasm contained long, winding channels of smooth endoplasmic reticulum, vacuoles, and myelin figures. Fluid retention in the small intestine due to administration of cytotoxic drugs is suggested as a possible mechanism for distention of the mitochondria.

Effects of anesthesia based on large versus small doses of fentanyl on natural killer cell cytotoxicity in the perioperative period

Surgical stress and general anesthesia suppress immune functions, including natural killer cell cytotoxicity (NKCC). This suppression could be attributable, at least in part, to opiates. We have previously shown that large-dose fentanyl administration suppressed NKCC in rats. The present study sought to compare the effects of two anesthetic protocols, based on large- (LDFA) versus small (SDFA)-dose fentanyl anesthesia on NKCC in the perioperative period. Forty patients were included in this study; half were assigned to each protocol of anesthesia. In each anesthetic group, half the patients were undergoing surgery for malignant diseases, and half for benign conditions. Blood samples were collected during the perioperative period. NKCC was assessed using the chromium release assay. Initially, both types of anesthesia similarly suppressed NKCC, with a peak effect 24 h after surgery. The two types of anesthesia, however, differed in the rate of recovery of NKCC suppression. By the second postoperative day, NKCC returned to control values in the SDFA patients, whereas NKCC was still significantly suppressed after LDFA. These results indicate that LDFA causes prolonged suppression of NK cell function. Whether this suppression might have a long-term impact on the overall outcome, especially in cancer patients, remains to be determined.

Effect of halothane on phenylephrine-induced vascular smooth muscle contractions in endotoxin-exposed rat aortic rings

OBJECTIVES

a) To determine the response of endotoxin-exposed vascular smooth muscle to exogenous vasoconstrictors during concomitant exposure to an inhaled anesthetic (halothane); and b) to determine if excess nitric oxide production is responsible for any altered response.

DESIGN

In vitro, prospective, repeated-measures, dose-response study.

SETTING

University/medical school experimental physiology laboratory.

SUBJECTS

Adult male Sprague-Dawley rats, whose aortae were studied in an in vitro preparation.

INTERVENTIONS

Thoracic aortae were excised from anesthetized animals and cut into 3-mm rings. After incubation in aerated organ baths containing a modified essential medium with or without Escherichia coli lipopolysaccharide (100 micrograms/mL) at 37 degrees C for 5 hrs, the rings were removed and suspended in separate baths for isometric tension recording. Phenylephrine dose-response data (10(-10) to 10(-5) M) were determined for lipopolysaccharide- and nonlipopolysaccharide-treated rings. After washout and equilibration, two vessels (one each lipopolysaccharide- and nonlipopolysaccharide-treated) were additionally exposed to 2% halothane and phenylephrine dose-response determinations were repeated for all vessels. This procedure was repeated for 1% halothane in a separate experiment. In some experiments, the nitric oxide synthase inhibitor, N omega-nitro-L-arginine (3 x 10(-4) M), was added to the bath after the washout from the second phenylephrine dose-response determination. Then, a third phenylephrine dose-response determination was performed, with and without 2% halothane.

MEASUREMENTS AND MAIN RESULTS

Dose-response curves were evaluated using a logistic regression analysis. In addition, absolute and percentage changes in tension were compared between the first and second contractions. Exposure to lipopolysaccharide resulted in a decrease in the maximum tension from 2.07 +/- 0.03 (controls) to 1.24 +/- 0.04 g/mg of vessel dry weight and an increase in the dose at which the contraction is 50% of maximum (ED50) from 3.78 x 10(-8) to 2.05 x 10(-7) M (p < .05). Exposure to 2% halothane produced significant reductions in the maximum tensions in both groups. The lipopolysaccharide-treated vessels showed not only a proportionately larger decrease (-51 +/- 5% vs. -18 +/- 2% in the control plus halothane group), but also a significantly greater absolute decrease (0.59 +/- 0.09 vs. 0.34 +/- 0.04 g/mg in the control plus halothane group). The addition of 1% halothane produced less pronounced decreases in tension, with only an additive effect in the lipopolysaccharide-treated vessels. The addition of N omega-nitro-L-arginine resulted in a reversal of the lipopolysaccharide-induced decrease in tension. However, 2% halothane still had a significantly greater effect on the lipopolysaccharide-exposed rings.

CONCLUSIONS

Exposure of rat aortic rings to lipopolysaccharide in vitro decreased the contractile response to phenylephrine. The addition of 2% halothane resulted in a more than additive decrease in tension in the lipopolysaccharide-treated vessels. Patients in septic or endotoxic shock are sensitive to most anesthetic regimens, and some of this sensitivity may be due to an altered vasoconstrictive response induced by lipopolysaccharide exposure. The inability of nitric oxide synthase inhibition to reverse this response completely suggests that induction of nitric oxide synthase and increased production of nitric oxide are not solely responsible for this finding.

Human colostrum stimulates cytokine production

The effect of human colostrum on the production of IL-1, IL-3 and IL-6 by peripheral blood mononuclear cells (PBMCs) has been investigated. The aqueous phase of human colostrum significantly stimulated the production of these three cytokines. These findings show the importance of breast feeding not only as a well-balanced nutrient supply but also as a source for growth-promoting factors. It is suggested that the enhanced secretion of IL-1, IL-3 and IL-6 induced by human colostrum may compensate for the lower capacity of neonatal PBMCs to produce these cytokines. It is also possible that, by stimulating the secretion of these cytokines, breast feeding may provide an additional mechanism for the regulation of the neonatal immune system and hematopoiesis.