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PubMedDate not supplied

Application of strategically designed sample composition to the rapid analytical screening of milk samples for polychlorinated biphenyls.

Strategically designed sample composition (SSC) is a new technique that decreases the number of analytical determinations needed in routine screening to as few as the number of original sample specimens while providing information that is specific to them. Although this new technique has been applied to environmental studies, this paper describes its first application to food safety studies. Contamination of milk samples with polychlorinated biphenyls (PCBs) was chosen as a case study to show the usefulness and potential of the SSC technique with a fast analytical procedure that involves saponification of the samples and solid-phase microextraction of the PCBs. A total of 20 sample specimens can be analyzed in 11 determinations with excellent predictions of the positive samples and the concentration levels of the contaminants. The robustness of the strategy was investigated and demonstrated.

Animals↗
PubMed1997

Family practice physicians' firearm safety counseling beliefs and behaviors.

The purpose of this study was to identify family physicians' firearm safety counseling beliefs and behaviors. A survey was mailed to a random sample of 600 members of the American Academy of Family Physicians. A three wave mailing technique was used to maximize the response rate and yielded 271 usable surveys (55% response rate). Outcome measures included training experience in firearm safety counseling, the prevalence of firearm safety counseling by family physicians, and their perceptions regarding such counseling. The majority (78%) of family physicians lacked formal training on how to counsel patients about firearm safety and 49% believed more time should be spent in residency programs on firearm safety counseling. The majority (84%) of respondents never or rarely counseled patients on firearm safety and 50% believed firearm safety counseling should be a low priority in their delivery of primary care. The majority of respondents did not regularly counsel patients about firearm safety, did not believe firearm safety counseling should be a priority, and did not believe firearm safety counseling would be effective in reducing firearm-related trauma.

Attitude of Health Personnel↗
PubMedDate not supplied

1H-NMR for the safety control of food packaging materials: analysis of extracts from polyolefin samples.

A new approach for the identification of the additives in extracts of packaging plastics, using proton nuclear magnetic resonance (1H-NMR), is presented. The technique can be used in a preliminary step for the determination of contaminants potentially released by the food packaging materials; it may greatly reduce the time required to identify the constituents of the materials, either individually or as functional classes. A classification of the EEC additives is proposed on the basis of chemical shift. 1H-NMR can also be used as a fingerprint technique in the quality control of the food packaging materials.

Chromatography↗
PubMed2006

Diffusive sampling of airborne furfural by solid-phase microextraction device with on-fiber derivatization.

The solid-phase microextraction (SPME) device was used as a diffusive sampler for airborne furfural. The polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber was used, and O-2,3,4,5,6-(pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) was first loaded onto the fiber. The SPME fiber assembly was then inserted into a PTFE tubing as a diffusive sampler. Known concentrations of furfural around the threshold limit values (TLVs)/time-weighted average and specific relative humidities (RHs) were generated by syringe pumps in a dynamic generation system. Validations of the SPME diffusive sampling with the US Occupational Safety and Health Administration (OSHA) organic method 72 were performed side-by-side in an exposure chamber at 25 degrees C. Gas chromatography/mass spectrometry (GC/MS) was used for sample analysis. The experimental sampling constant of the sampler was found to be (1.75 +/- 0.03) x 10(-2) (cm3 min(-1)) at 25 degrees C, whereas face velocity (0-0.25 ms(-1)) as well as RHs (10-80%) were proven to have no effects on the sampler. The correlations between the results from both SPME device and OSHA organic method 72 were found to be linear (r = 0.9849) and consistent (slope = 0.99 +/- 0.03). However, the variations of diffusion coefficients at different temperatures needs to be considered, and the adjustment of sampling constant was a must when sampling at temperatures different from 25 degrees C.

Chromatography, Gas↗
PubMed2001

A proficiency testing scheme for aromatic hydrocarbons in air by the manual thermal desorption-GC method: a comparison of laboratory performance with the uncertainty requirements of the European Union Ambient Air Directive.

The Workplace Analysis Scheme for Proficiency (WASP) is a proficiency testing scheme for the analysis of occupational hygiene and environmental air samples and is operated in the UK by the Health and Safety Laboratory. Since 1997, WASP has offered samples of benzene, toluene and m-xylene, at environmental levels on Tenax, and has about 35 laboratories participating, mostly from industry, local government and consultancy organisations in the UK. The results reported cover the first 10 rounds of the environmental analytes (1997-1999) and demonstrate the important role of proficiency testing in assessing the quality of laboratory performance. Estimates are obtained for within-laboratory precision and the total variability at each analyte level. The estimates of within-laboratory precision suggest that laboratories have more difficulty analysing toluene and m-xylene than benzene. Linear relationships for the reproducibility relative standard deviation (RSDT) with loading level are evident for the analytes at occupational levels. At environmental levels, the relationship between loading level and reproducibility is much less well defined. The standard deviation for the proficiency testing assessment for all three analytes at the environmental level is 14%, as derived from the benzene data. Expanded uncertainty estimates (k = 1.96), for the analysis of samples since the scheme started, are obtained from the average total variance, and are 27% for benzene, 39% for toluene and 36% for m-xylene. Although the linear trend of performance against round number was not significant at the 95% level of confidence (p = 0.23 for benzene, p = 0.3 for toluene and p = 0.32 for m-xylene), there was a general improvement in RSDT from 26-34% to about 8-13% 10 rounds later. Currently, for a laboratory to meet one of the data quality objectives in the Ambient Air Directive (indicative measurement of benzene, expanded uncertainty +/- 30% or less), it would have to achieve a level of analytical performance to satisfy the category 1 (best performance) limit of better than +/- 8.8%. In the last proficiency testing round, discussed in this paper, only 58% of laboratories obtained performance scores that indicated that they were able to consistently achieve this level of performance.

Air Pollutants↗
PubMed1999

Feasibility and functionality of OROS melatonin in healthy subjects.

OROS (melatonin), an oral osmotic system for controlled drug delivery, was evaluated in an open-label, two-way crossover study to test the feasibility of continuous overnight melatonin delivery. Twelve healthy subjects with no sleep disorders, ranging from 60 to 73 years of age, were enrolled in the study. Two doses of melatonin (1 x 110 micrograms and 4 x 110 micrograms) were administered on two separate occasions. Endogenous baseline nighttime serum melatonin concentrations were measured the night before each treatment. Following treatment at 2100 hours, the lights were extinguished at 2200 hours and remained so, except during blood sample collection, which was performed under dim light (< 50 lux) at specified times. Serum samples were analyzed for melatonin by an LC/MS/MS method. In addition, safety measurements such as vitals and serum samples for endocrine functions were measured both prior to and after melatonin dosing. The serum melatonin concentration profile following OROS (melatonin) dosing mimicked the normal endogenous serum melatonin concentration-time profile. The mean maximal melatonin concentration occurred at 3 a.m. The mean AUCs of endogenous melatonin before the two treatment days were 248 and 234 pg.h/mL, respectively. Serum concentrations of melatonin corrected for endogenous production increased proportionally with dose, with AUCs of 288 and 1069 pg.h/mL, respectively. Deconvolution of the serum concentration data showed good correlation between the in vitro amount released and the in vivo amount absorbed, suggesting continuous absorption throughout the gastrointestinal tract. Less than 5% residual content was observed in the recovered OROS system. Minimal changes in serum hormone concentrations (luteinizing hormone, follicular stimulating hormone, and prolactin) and no serious adverse events were observed following OROS treatment in these subjects. Delivery of melatonin with OROS formulation may result in a physiologic nocturnal profile in elderly subjects.

Adjuvants, Immunologic↗
PubMed2003

Donepezil in the treatment of mild to moderate Alzheimer's disease: report of a Belgian multicenter study.

In this report the results of a Belgian multicenter 24-week open-label study with donepezil in the treatment of mild to moderate Alzheimer's disease are described. Efficacy and safety were evaluated in a sample of 200 patients recruited in 25 Belgian centers. No significant changes could be found in cognition and behaviour over this 6-month period. Changes in daily functioning were small. Safety data were comparable to those reported in international trials. These results suggest that the findings of more robust double-blind, placebo-controlled studies can be confirmed in real life situations.

Activities of Daily Living↗
PubMed2004

First-trimester fetal reduction to a singleton infant or twins: outcome in relation to the final number and karyotyping before reduction by transabdominal chorionic villus sampling.

OBJECTIVE: The purpose of this study was to evaluate fetal outcome and maternal complications of multifetal pregnancy reduction to a single fetus or twins. To evaluate safety and efficacy of transabdominal chorionic villus sampling for karyotyping before fetal reduction. STUDY DESIGN: Four hundred twenty-four consecutive multiple pregnancies were reduced to twins (255 pregnancies) or a single fetus (169 pregnancies) at 8 to 13 weeks of gestation after transabdominal chorionic villus sampling for fetal karyotyping. Fetal and maternal outcome were observed prospectively and compared with control series of twin (147) and singleton (885) pregnancies in which reduction procedures were not performed. RESULTS: Transabdominal chorionic villus sampling was performed successfully in 100% of the cases. The accuracy of karyotyping was 99.2%. The overall pregnancy loss rate after reduction was 3.3%. No differences were observed between study and control series for severe prematurity, low birth weight, and neonatal deaths. Mean gestational age at delivery (35.2% vs 38.1%) and mean birth weight (2180 g vs 2873 g) were significantly lower; preterm delivery (64% vs 11%), neonatal death (3.4% vs 0.6%), and maternal complications (42.8% vs 9.5%) were significantly higher when the reduction was to twins rather than in reduction to a single fetus. Pregnancy loss rate did not differ between study series. The overall rate of chromosomal abnormalities in the study series was higher (relative risk, 2.0) than in singleton control series. CONCLUSION: The outcome of multiple pregnancies that were reduced to a single fetus or twins was similar to that of nonreduced pregnancies; fetal and maternal complications were significantly lower in the series of pregnancies that were reduced to a single fetus. The safety and efficacy of transabdominal chorionic villus sampling and the higher pregnancy rate of chromosomal abnormalities in multiple pregnancies imply that fetal karyotyping should be advised before fetal reduction.

Adult↗
PubMed1997

Laboratory comparison of vacuum, OSHA, and HUD sampling methods for lead in household dust.

The goals of this project were to evaluate and compare the efficiency and reproducibility of three methods for sampling lead-containing dust in homes. Lead-containing dust was generated in a 1-m3 chamber and uniformly deposited onto surfaces typically found in the home (painted wood, unpainted wood, varnished wood, linoleum, and carpet). Trials with three levels of lead concentrations were performed for each surface. Replicate, side-by-side, surface samples were collected using the Occupational Safety and Health Administration (OSHA) wipe method, the Department of Housing and Urban Development (HUD) wipe method, and a vacuum-filter method. Samples were digested with nitric acid and analyzed using graphite furnace atomic absorption spectroscopy per National Institute of Occupational Safety and Health Method 7105. Recovery for the HUD method was consistently the highest on most surfaces (linoleum, 89.9 to 108.9%; painted wood, 71.2 to 153.7%; unpainted wood, 25.3 to 76.0%; varnished wood, 8.7 to 165.6%). On carpet the vacuum method had a significantly higher recovery (26.2 to 47.8%). For all sampling methods the percent recovery depended on type of surface and lead concentration. The reproducibility of percent recovery for the HUD (pooled coefficient of variation [CV] = 0.22) and OSHA (pooled CV = 0.27) methods was lower than that of the vacuum method (pooled CV = 0.46), though not statistically significant. Reproducibility for all methods did not vary significantly over surface type or lead concentration. Overall, the HUD method yielded the most accurate measurements, with recoveries closest to 100%. It was also more durable than the OSHA method, where Whatman filters were observed to tear.

Child, Preschool↗
PubMed1996

Farm health and safety issues: do men and women differ in their perceptions?

This study identifies gender specific farm health and safety issues. Based on a sample from the 1988 New York Farm Family Survey, descriptive statistics and exploratory factor analysis were used to establish unique gender based profiles in terms of labor force participation, and prioritization of farm health and safety issues, concerns, and information sources. Based on the factor analysis, women's main farm health and safety issues included physical problems and occupational hazard screening needs, provider integrity, and economic incentives. Men's main issues consisted of accident related counseling needs, skin related hazards, and the farm related convenience of the services. Men and women had statistically significant differences in the types of information sources and reasons for using farm health and safety services. These differences imply that farm health and safety providers must consider both gender related information gathering and farm health and safety prioritizations to more efficiently allocate intervention resources, more effectively promote safety, and reduce the incidence of occupationally related morbidity and mortality in agriculture.

Agriculture↗
PubMed1997

The safety of fetal pulse oximetry in parturients requiring fetal scalp blood sampling.

OBJECTIVE: To determine whether maternal or fetal morbidity is increased in association with fetal pulse oximetry monitoring using an atraumatic intrapartum transcervical fetal oxisensor. METHODS: In a prospective cohort study from January 1993 to June 1996, 196 fetuses were monitored during the intrapartum period with a fetal oximetry sensor placed between the uterine wall and the presenting fetal part. The oxisensors were in position for a median duration of 134 minutes. A total of 101 monitored fetuses underwent intrapartum fetal scalp blood sampling because of nonreassuring heart rate tracings. For a control group, we selected all cases during the same period in which fetal blood sampling was performed in the intrapartum period (n = 949) without pulse oximetry monitoring. Data for maternal and fetal morbidity were evaluated and tested for significant differences by the Mann-Whitney U test. RESULTS: There was no significant difference in gestational age, birth weight, duration of labor, fetal outcome parameters, cesarean rate, operative vaginal deliveries, episiotomy rate, or perineal injuries between the study and control groups. Similarly, the percentages of neonatal intensive care unit admissions, neonatal resuscitations, and neonatal infections were not statistically different in the two groups. A rare complication in the group with pulse oximetry monitoring was a transient impression of the oxisensor probe on the fetal cheek. The rates of postpartum maternal infections, anemia, or secondary wound disruptions were identical in both groups. CONCLUSION: There was no increased fetal or maternal morbidity associated with the use of an atraumatic intrapartum fetal pulse oxisensor.

Female↗
PubMed1977

The reliability of the examination of foods, processed for safety, for enteric pathogens and Enterobacteriaceae: a mathematical and ecological study.

Because of the paucity of quantitative data on numbers of other enteric pathogens in food, the reliability of the examination of processed foods for Enterobacteriaceae was estimated taking Salmonella as a model. For this purpose an assessment was carried out of the risk of accepting Salmonella contaminated consignments of foods, despite a negative outcome of (i) examination of 1.5 kg samples for Salmonella; (ii) examination of one or two 1 g samples for Enterobacteriaceae; (iii) simultaneous application of both tests. The computations were based on the results of the examination of 6830 samples of dried foods, processed for safety, out of a total of 18170 samples.Only 69 samples permitted the exact calculation of the epsilon-factor, defined as c.f.u./g of Enterobacteriaceae/c.f.u./g of Salmonella; 4642 were positive for the former group but ;free' from Salmonella, and the rest were negative in both tests. Numbers of c.f.u./g for both groups, and hence the epsilon-factors, varied widely between commodities and also between different consignments of the same food product. The average for epsilon amounted to 5.8 x 10(3), far from the base-line value of 0.75 x 10(3) assessed earlier. In only 0.1% of samples did the Enterobacteriaceae test fail to achieve the required consumer protection.This investigation therefore substantiates that testing foods processed for safety by examining accurately chosen quantities for ecologically well selected and taxonomically thoroughly defined index organisms is a most effective procedure in terms both of consumer protection and simplicity of examination without compelling the food industry to achieve hardly attainable microbiological quality standards.

Bacteriological Techniques↗
PubMed2004

Fundamentals of cryobiology in reproductive medicine.

The aim of this review will be to provide a basic understanding of the biophysical processes that accompany the application of cryopreservation in reproductive medicine. The ability to store cells in 'suspended animation' outside the body has become a keystone practice in the development of many modern clinical therapies, and, in fact, the sciences of cryobiology and IVF have developed in parallel over the past 50 years. During this time, some of the underlying principles of the quantitative biophysical aspects of cryobiology have been clarified. Water is the universal biocompatible solvent, but also possesses unique properties for stability of living cells. Whilst low temperatures themselves have defined effects on cell structure and function, it is the phase transition of water to ice that is the most profound challenge for survival. The thermodynamics of dilute aqueous solutions dictate how cells and tissues respond to the freezing process. Current concepts of nucleation, ice crystal growth and solute exclusion from the ice lattice will be discussed to illustrate what cells must negotiate to avoid lethal damage, and the role of cryoprotectants in enhancing recovery. Quantitative formalisms now exist to model and predict how water and solutes move across cell membranes before and during freezing, or how nucleation events will proceed, and these will be outlined. Cryoprotectants have both positive and negative effects on cell function depending on the kinetics of exposure. The concept of tolerable osmotic excursion of cell volume will be discussed, along with the evidence for a 'pseudo-glassy' state for cells during traditional cryopreservation. This will be compared with the recent interest in promoting glassy states in the whole sample using vitrification protocols, outlining the advantages and drawbacks of each approach. Additional methods for controlling ice nucleation have a role to play here, and a brief outline of current technologies will be given. Finally, issues of safety and stability of cryopreserved samples will be set out.

Cell Physiological Phenomena↗
PubMed2006

Cheerleading-related injuries to children 5 to 18 years of age: United States, 1990-2002.

OBJECTIVE: To describe the epidemiology of cheerleading-related injuries among children in the United States. DESIGN: A retrospective analysis of data for children 5 to 18 years old from the National Electronic Injury Surveillance System (NEISS) of the US Consumer Product Safety Commission, 1990-2002. METHODS: Sample weights provided by the NEISS were used to make national estimates of cheerleading-related injuries. Injury rates were calculated for the most frequently occurring types of injury using cheerleading participation data. RESULTS: An estimated 208,800 children (95% confidence interval [CI]: 166,620-250,980) 5 to 18 years of age were treated in US hospital emergency departments for cheerleading-related injuries during the 13-year period of 1990-2002. The number of injuries increased by 110% from 10,900 in 1990 to 22,900 in 2002, with an average of 16,100 (95% CI: 12,848-19,352) injuries per year (P < .01). The average age of injured children was 14.4 years (median: 15.0 years); 97% were female; and 85% of injuries occurred to children 12 to 17 years old. The number of injuries per 1000 participants per year was greater for 12- to 17-year-olds (8.1) than for 6- to 11-year-olds (1.2) for all cheerleading-related injuries combined (P < .01; relative risk [RR]: 6.49; 95% CI: 6.40-6.58), as well as for injuries grouped by body part injured and type of injury. The body parts injured were lower extremity (37.2%), upper extremity (26.4%), head/neck (18.8%), trunk (16.8%), and other (0.8%). Injury diagnoses were strains/sprains (52.4%), soft tissue injuries (18.4%), fractures/dislocations (16.4%), lacerations/avulsions (3.8%), concussions/closed head injuries (3.5%), and other (5.5%). Children in the 12- to 18-year age group were more likely to sustain strains or sprains to the lower extremity than 5- to 11-year-olds (P < .01; RR: 1.62; 95% CI: 1.50-1.88). The majority of patients with cheerleading-related injuries was treated and released from the emergency department (98.7%). Patients sustaining fractures or dislocations were more likely to be admitted to the hospital than those sustaining other types of injury (P < .01; RR: 5.30; 95% CI: 3.29-6.43). CONCLUSIONS: To our knowledge, this study is the first to report numbers, rates, and trends of cheerleading-related injuries to children using a nationally representative sample. Cheerleading is an important source of injury to girls. The number of cheerleading-related injuries more than doubled during the 13-year study period. A set of uniform rules and regulations directed at increasing the safety of cheerleading, that are universally enforced, should be implemented. Mandatory completion of a safety training and certification program should be required of all cheerleading coaches. Establishment of a national database for cheerleading-related injuries would facilitate the development and evaluation of injury-prevention strategies based on epidemiologic evidence.

Adolescent↗
PubMed2003

Human immunodeficiency virus-1 and hepatitis C virus RNA among South African blood donors: estimation of residual transfusion risk and yield of nucleic acid testing.

BACKGROUND AND OBJECTIVES: South Africa is an endemic area for human immunodeficiency virus 1 (HIV-1) infection, which has an impact on the safety of the blood supply. We studied the presence of HIV-1 and hepatitis C virus (HCV) RNA, and recent HIV seroconversion, in blood donors in order to estimate transfusion risk and to determine whether nucleic acid testing (NAT) could effectively improve blood safety. MATERIALS AND METHODS: Unlinked samples collected in 1999 from 9077 HIV-low prevalence (LP) and 10,632 HIV-high prevalence (HP) donors were studied. Donor demographic information and serology results were collected prior to breaking the linkage. All samples were individually tested using a multiplex NAT assay for HIV-1 and HCV RNA. HIV antibody-positive samples were further tested using a 'detuned' (less sensitive) enzyme immunoassay (EIA) procedure to determine whether a donor had recently acquired infection. Data were used to estimate the residual transfusion risk and to project NAT yield. RESULTS: HIV was 45 times more prevalent in the HP- than in the LP donor group; and among the HP group, female donors had a significantly higher prevalence of HIV than male donors. All seven HIV-1 p24 antigen-positive samples in the study were also HIV NAT positive. Two HIV NAT-positive samples were anti-HIV negative; both of these samples were from HP donors. Assuming that 10% of the 900,000 annual donations in South Africa are from the HP group, we projected an annual NAT yield of 8.5 cases over the current screening of antibody and p24 antigen. However, if p24 antigen testing were to be eliminated, this number would be increased to 17 cases per year. Based on 'detuned' EIA results, the incidence rate for HIV infection was estimated at 1.29 and 51.12 per 10,000 per year for the LP and HP donor groups, respectively. Assuming a 15-day earlier detection by HIV NAT compared with antibody tests, these incidence rates project that NAT may intercept an additional 23 (95% confidence interval: 15-33) HIV-positive donations per year. For HCV, two viral RNA and antibody-positive samples (one from the LP group and one from the HP group) and no NAT yield cases were found in the study. CONCLUSIONS: Implementation of routine NAT blood screening would allow elimination of HIV-1 p24 antigen testing and improve the safety of the blood supply in South Africa. However, the cost-benefit ratio of introducing such an expensive technology in a country with a limited health budget will have to be carefully considered.

Adult↗
PubMed2006

When and why do experts perform exposure measurements? An exploratory study of safety engineers, work environment inspectors, and occupational hygienists.

The aim of this study was to describe experts' decision processes leading to measurements of occupational chemical exposure. Safety engineers, clinical occupational hygienists, and work environment inspectors (four from each group) were interviewed according to a semistructured scheme. We analyzed: (i) perceived triggers for measurements, (ii) the experts' decision criteria for performing measurements when there was a trigger, and (iii) sampling strategy. Regarding triggers, all safety engineers reported a "request" from, for example, an employer; all work environment inspectors reported "legal demands;" and all clinical occupational hygienists reported "symptoms among workers." As a decision criterion, all the interviewees reported that they measured only if they expected sufficiently high levels. The results of the present study highlight factors that trigger measurements and are of importance in determining whether measurements will be performed. These factors appear to be related to the expert's professional role and may bias the assessment of exposure. Thus, when using data from routine measurements done by experts, the possibility of a bias needs to be considered.

Decision Making↗
PubMed1995

Comparison of transcervical and transabdominal chorionic villus sampling loss rates in nine thousand cases from a single center.

OBJECTIVES: Our purposes were (1) to compare the safety of transabdominal and transcervical chorionic villus sampling with the use of a consistent technique at one center and (2) to determine whether the training of fellows can be accomplished without an increase in the loss rate. STUDY DESIGN: We performed a retrospective comparison of transabdominal and transcervical chorionic villus sampling loss rates from procedures performed by three principal operators between 1984 and 1992. The type of procedure was chosen by the operator at the time of the procedure on the basis of placental location. RESULTS: Procedures 1 through 2573 were performed solely by transcervical chorionic villus sampling and had an overall fetal loss rate of 5.12%. With the addition of transabdominal chorionic villus sampling the overall fetal loss rate dropped to 3.07% (p < 0.0001). Three and one half years after the start of transabdominal chorionic villus sampling (about 1300 transabdominal chorionic villus sampling procedures), the transabdominal chorionic villus sampling loss rate was significantly better than the transcervical loss rate (p = 0.035), and the difference widened steadily after that. During the same time period seven fellows performed 716 procedures for a fetal loss rate among fellows of 2.72%. CONCLUSIONS: (1) Under optimal circumstances (one center, large numbers, few operators, consistent technique, operator choice of best approach), transabdominal chorionic villus sampling may be inherently safer than transcervical chorionic villus sampling. (2) The addition of transabdominal chorionic villus sampling decreases overall chorionic villus sampling loss rates. (3) Although the number of procedures performed by fellows is small, it appears that with close supervision by experienced operators successful training of fellows can be accomplished without adverse effects on loss rates.

Chi-Square Distribution↗
PubMed1999

Administration of hypertonic (3%) sodium chloride/acetate in hyponatremic patients with symptomatic vasospasm following subarachnoid hemorrhage.

A retrospective study was carried out to evaluate the effect of hypertonic (3%) saline chloride/acetate on various hemodynamic parameters in mildly hyponatremic patients with symptomatic vasospasm following aneurysmal subarachnoid hemorrhage (SAH). We identified 29 hyponatremic (serum sodium < 135 mEq/L) patients who received hypertonic (3%) sodium chloride/acetate as a continuous infusion. Administration of hypertonic (3%) sodium chloride/acetate resulted in higher central venous pressures and positive fluid balance, with a concomitant increase in serum sodium and chloride concentrations without metabolic acidosis. There were no changes in mean cerebral blood flow velocities after infusion of hypertonic (3%) sodium chloride/acetate. We found no reports of congestive heart failure, pulmonary edema, metabolic acidosis, coagulopathy, intracranial hemorrhages, or central pontine myelinolysis in any of these patients. We conclude that hypertonic (3%) sodium chloride/acetate can be administered to patients with mild hyponatremia in the setting of symptomatic vasospasm following SAH without untoward effects. Sample size and limitations of a retrospective analysis preclude conclusions about safety and efficacy of hypertonic (3%) sodium chloride/acetate administration in this patient population. However, our results support justification for a prospective, randomized, double-blind trial of hypertonic (3%) sodium chloride/acetate versus normal saline in patients with symptomatic vasospasm following SAH.

Acetates↗