Immediate cardiovascular effects of the Taser X26 conducted electrical weapon

STUDY OBJECTIVES

To evaluate the immediate cardiac and cardiovascular effects of Taser X26 conducted electrical weapon (CEW) exposure in human volunteers, including heart rhythm, rate and blood pressure.

METHODS

Volunteer police officers participating in CEW training and testing each underwent a 5, 3 and 1 s exposure to the Taser X26 CEW. Continuous electrocardiogram (ECG) monitoring was performed before, during and after each exposure. Blood pressures were measured at rest before and within 1 minute after each exposure. Paired sample t-test analysis and confidence interval calculations were performed.

RESULTS

84 Taser exposures were monitored among 28 subjects (24 men, four women) with an average age of 34 years (range 24-46, SD 5.6). No cardiac dysrhythmias or aberrantly conducted beats were seen. Mean heart rate increased by 10.9 beats per minute (bpm) (95% CI 8.2 to 13.7) from 121.7 to 132.6 (p<0.001). The QRS and QTc cardiac intervals did not change significantly. Mean blood pressure increased from 138.6/82.8 mm Hg at rest to 145.8/85.6 mm Hg after the standard 5-s CEW discharge.

CONCLUSION

CEW exposure produced no detectable dysrhythmias and a statistically significant increase in heart rate. Overall, Taser CEW exposure appears to be safe and well tolerated from a cardiovascular standpoint in this population. This study increases the cumulative human subject experience of CEW exposure with continuous ECG monitoring and includes 28 full 5-s exposures.

Reference dose (RfD): the possible impact of hormesis

A fictitious US Environmental Protection Agency Administrator in the year 2005 is confronted with making a risk management decision on a chemical that exhibits an unambiguous hormetic effect in an animal system. Dose-response curves for average humans and sensitive humans are derived from the animal data. The question is posed: What should the reference dose (RfD) be in this case? A series of outstanding scientific and policy questions are discussed that have a bearing on the answer. The concept of the 'regulatory dose (RgD)' is revived to address, if not resolve, the issue.

Catheter-free endoscopic laser ablation of the prostate using a 1-size prostatic stent

PURPOSE

Endoscopic laser ablation of the prostate is a safe alternative to transurethral prostatic resection. Recognized disadvantages include prolonged catheterization, postoperative discomfort and delayed symptomatic improvement. We assessed the role of a 1-size temporary prostatic stent in men undergoing endoscopic laser ablation of the prostate.

MATERIALS AND METHODS

A total of 55 men a mean of 73 years old with outflow obstruction, including 9 who presented in urinary retention, underwent endoscopic laser ablation of the prostate and temporary stenting. Urinary flow rate, residual urine volume, symptom score and prostate specific antigen were measured preoperatively, and 6 weeks (with the stent in situ), 3 months (after stent removal) and 12 months postoperatively. Duration of hospital stay and complications were also recorded.

RESULTS

Of the 55 men 37 (67%) voided immediately with the stent in situ, including 7 of the 9 in retention. At 6 weeks with the stent in place mean maximum urine flow was 17.3 ml. per second (preoperatively 8.7). Dysuria was reported by 3 patients. Stent related complications were rare. One stent migrated early, resulting in urinary retention, while 2 that migrated late were asymptomatic. No patient had acute urinary retention after stent removal. Maximum urinary flow rate measured at 6 weeks with the stent in situ was similar to that 1 year after endoscopic laser ablation of the prostate.

CONCLUSIONS

The use of a 1-size, inexpensive plastic prostatic stent enabled catheter-free endoscopic laser ablation of the prostate in 67% of our patients. Early improvements in the urinary flow rate and a lower incidence of dysuria were additional benefits. The result of endoscopic laser ablation of the prostate at 1 year was comparable to that of transurethral prostatic resection.

Future of Environmental Pollution

In recent years, the concept of pollution prevention has overtaken end-of-pipe controls as the paradigm of choice for effecting environmental protection. Through cooperative mechanisms, significant progress Is being made to reduce or eliminate upstream processes and practices that can lead to downstream pollution. These efforts, coupled with productive interactions with the public, are making an impact. The Science Advisory Board released a report in January that described the “next wave” of pollution prevention. Specifically, the report described approaches for anticipating environmental problems of tomorrow so that preventive actions can be taken today. The potential of air pollution problems figures prominently in the Board's vision of the future.

Future of environmental pollution

In recent years, the concept of pollution prevention has overtaken end-of-pipe controls as the paradigm of choice for effecting environmental protection. Through cooperative mechanisms, significant progress is being made to reduce or eliminate upstream processes and practices that can lead to downstream pollution. These efforts, coupled with productive interactions with the public, are making an impact. The Science Advisory Board released a report in January that described the "next wave" of pollution prevention. Specifically, the report described approaches for anticipating environmental problems of tomorrow so that preventive actions can be taken today. The potential of air pollution problems figures prominently in the Board's vision of the future.

Benchmark Dose Workshop: criteria for use of a benchmark dose to estimate a reference dose

The purpose of the Benchmark Dose Workshop was to assess the feasibility and implications of replacing the no observed adverse effect level (NOAEL) with a benchmark dose (BMD) when deriving reference doses and concentrations (RfDs and RfCs). The workshop participants supported the use of the BMD method to remove many of the limitations inherent in using the NOAEL approach. Participants endorsed in general the use of a BMD for all quantal noncancer health effects and endorsed in particular the BMD for assessing developmental toxicity based on data presented at the workshop. The discussions of implementation recognized the need to demonstrate that changing from a NOAEL to a BMD gives the risk manager more certain information on which to base decisions. Most participants agreed that the current NOAEL-derived RfDs and RfCs are sufficiently protective and should only be changed as data become available for estimating a BMD. It was recognized that to achieve general acceptance of the BMD approach, it will have to be applied to a variety of endpoints.

Absorption of silicon and aluminum by hens fed sodium zeolite A with various levels of dietary cholecalciferol

Two experiments were conducted to determine whether 1) serum Si and Al is increased in hens intubated with sodium zeolite A (SZA); and 2) dietary cholecalciferol (vitamin D3) influences the absorption of Si or Al by hens fed SZA. In Experiment 1, hens were intubated at oviposition with 0, 1, or 2 g of SZA. Blood samples were collected from the brachial vein at oviposition, and 4, 8, 12, 16, and 20 h postoviposition. Serum samples were analyzed for Si and Al. Peak serum Si and Al were observed at 4 and 8 h postoviposition, respectively. In Experiment 2, hens consumed commercial layer diets ad libitum containing five levels of dietary cholecalciferol (100 to 500 IU/kg) with or without .75% SZA for 6 wk. Blood samples were collected at the end of the 6-wk period by cardiac puncture at oviposition. When dietary cholecalciferol was increased from 100 to 200 IU/kg of diet there was an increase (P < .05) in serum Si but not Al. Levels of cholecalciferol above 200 IU/kg did not produce an additional increase in serum Si. The results showed increased (P < .01) serum concentrations of Si and Al for hens intubated with or fed SZA. It was concluded that Si and Al from SZA are absorbed by commercial Leghorn hens, and a possible involvement of Si or Al should be considered in the mechanism of action of SZA associated with improved eggshell quality and bone development.

Temporary Prostatic Stenting and Androgen Suppression: A New Minimally Invasive Approach to Malignant Prostatic Retention

Urinary retention secondary to carcinoma of the prostate is usually treated by ‘channel’ transurethral resection of the prostate either performed alone or in combination with hormone manipulation. The combination of temporary prostatic stenting and androgen suppression may reduce the morbidity and mortality associated with this treatment.

We report on our initial experience using the combination of a temporary prostatic stent with the oral anti-androgen Flutamide in 10 patients with urinary retention or severe bladder outflow obstruction secondary to prostatic carcinoma.

Eight of the ten patients successfully voided and maintained normal voiding after stent removal. There were two treatment failures requiring prostatic resection.

We believe the cost of stenting and medication is entirely justified by patient preference and clearance of hospital beds.

Laser prostatectomy: our initial experience of a technique in evolution

Recently great interest has been generated in alternatives to transurethral resection for benign prostatic hyperplasia. Lasers are currently being assessed, but marketing has for the moment outstripped basic science. A cystoscopic approach was used delivering Nd:YAG or KTP laser energy via forward and sidefiring fibers and contact tip devices in 51 patients. The sidefiring device is intended to coagulate a volume of prostate that subsequently sloughs, leaving a cavity. Treatment of the apical and middle lobe tissue using this technique was unsatisfactory. A further disadvantage was the interval between treatment and improvement in urine flow, which was approximately 6 weeks. The use of temporary prostatic stents has helped to overcome this delay in treatment effect. Encouraging early results have been achieved using forward-firing fibers to treat apical and middle lobe tissue. The use of contact tip devices to perform bloodless prostatotomies in combination with sidefire or bare fiber has also proved useful. Laser prostatectomy is an exciting field with considerable potential but remains in the developmental stage.

Management of the neuropathic bladder by suprapubic catheterisation

Forty out-patients with neuropathic bladders managed by suprapubic catheterisation have been reviewed. Management included anticholinergic therapy and daily clamping of the catheter to maintain a compliant bladder of good capacity. Twenty-three females and 17 males (mean age 45 years) were studied. Failed intermittent catheterisation and the replacement of long-term urethral catheters were the main indications for suprapubic catheterisation. Catheter-related problems were common, with only 5 patients reporting none. Acceptance by patients was high (84%). No evidence could be found of accelerated renal deterioration in patients followed up for more than 2 years. A policy for the management of suprapubic catheters is recommended.

Evidence for absorption of silicon and aluminum by hens fed sodium zeolite A

The mechanism of action of zeolite A (ZA) on eggshell quality could be related either to its ion-exchange properties or to individual ZA elements (Al or Si). Two experiments were conducted to determine 1) whether any ZA passes through the digestive system in its original form; and 2) whether any Al and Si absorption occurs. In Experiment 1, unfed hens were intubated with either 0 or 5 g ZA at oviposition. In Experiment 2, fed and unfed hens were intubated at oviposition with 0, 1, or 2 g ZA. At the subsequent oviposition, liver and kidney tissues, excreta, urine, bile, and plasma were collected and analyzed for Al, Si, Na, K, and P. The results indicated that approximately 7% of the intubated ZA passed through the digestive system in its original form (Experiment 1). As the intubated level of ZA increased, excreta Al and Si (P < .0001), urine Si (P < .005), and urine Al (P < .07) also increased (Experiment 2). Aluminum recovery from excreta ranged from 75 to 93% of the quantity intubated in all treatments. Corresponding values of Si from excreta of unfed and fed hens ranged from 76 to 81% and 58 to 60%, respectively. The P content of excreta was not influenced by ZA. However, excreta P was greater (P < .0001) in unfed than in fed hens. Neither plasma electrolytes (Na, K, and P) nor Al or Si levels in either liver or kidney were influenced by ZA.(ABSTRACT TRUNCATED AT 250 WORDS)

Correlation of bacteriological flora of the urethra, glans and perineum with organisms causing urinary tract infection in the spinal injured male patient

Positive urine cultures are common and often asymptomatic in the male spinal injured patient performing self clean intermittent catheterisation. It is possible that the positive urine cultures result from contamination from the colonised urethra at the time of catheterisation. This contamination could result in true infection of the bladder urine or yield false positive results, explaining the frequently seen asymptomatic cases. In a prospective study positive urine cultures were found on 58 occasions (74%) in 10 asymptomatic patients studied. In 19% of screenings, with positive urine cultures, an identical organism was cultured from the catheter specimen of urine, the perineum and the urethra. The flora of the anterior urethra is strongly correlated to that of the perineum (37.1%), as well as that of the bladder (52.6%). In 4 patients a correlation also existed between the urethra and fingers, and the perineum and fingers. This was associated with an increased incidence of positive urine culture in these patients. Suprapubic aspirates of urine before and after catheterisation cultured the same organisms. However, quantitative culture revealed colony counts that approached a 10-fold increase following catheterisation in one patient. This suggests that catheterisation is at least partially responsible for ascending infection in this group of patients. Catheter specimens were found to be a good representation of the bladder urine, with an 87.5% correlation.

The effect of sodium zeolite A and cholecalciferol on plasma levels of 1,25-dihydroxycholecalciferol, calcium, and phosphorus in commercial Leghorns

Three experiments were conducted to determine possible mechanisms involved in improving eggshell quality with sodium zeolite A (SZA) (trade name Ethacal feed component), and cholecalciferol (vitamin D3) by studying the effect of dietary supplementation of SZA and vitamin D3 on plasma 1,25-dihydroxycholecalciferol [1,25-(OH)2 D3], ionic calcium (Ca++), normalized calcium (nCa++), total calcium (TCa), percentage Ca++ to TCa (PCa++), pH, and phosphorus (P). In Experiment 1 (2 x 2 factorial arrangement of treatments), two levels of SZA (0 and .75%) and two levels of vitamin D3 (0 and 175 ICU/kg) were fed. In Experiment 2, five levels of vitamin D3 (100 to 500 ICU/kg) and two levels of SZA (0 and .75%) were fed using a 2 x 5 factorial arrangement of treatments. In Experiment 3, hens were fed two levels of SZA (0 and .75%). Blood samples were collected at 0 (Experiments 1, 2, and 3), 7, 14, and 21 h (Experiment 3) postoviposition (POP). In Experiments 1 and 2, decreasing vitamin D3 decreased plasma 1,25-(OH)2 D3 and P. Plasma TCa decreased when 0 ICU vitamin D3 was fed (Experiment 1), but was not affected by vitamin D3 level in Experiment 2. Supplemental SZA had no effect on plasma 1,25-(OH)2 D3, TCa, or P in Experiments 1 and 2. In Experiment 3, plasma 1,25-(OH)2 D3 and P peaked at 14 h POP, but Ca++ was lowest at 14 h POP. Circadian rhythms for plasma 1,25-(OH)2 D3, Ca++, and P were not affected by SZA. There were no significant effects due to dietary SZA on plasma 1,25-(OH)2 D3, TCa, Ca++, PCa++, nCa++, pH, or P.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of sodium zeolite A with and without pullet-sized limestone or oyster shell on eggshell quality

To determine whether particle size of CaCO3 influences the hen's response to sodium zeolite A (ZA), two experiments were conducted. In Experiment 1, hens were fed 0, .75, and 1.50% ZA for 6 wk with and without a Na correction. At the end of the 4th wk, pullet-sized limestone was substituted for 50% of the added fine granular limestone in the diet containing no ZA. In Experiment 2, hens were fed diets containing 0, .68, and 1.36 ZA for 8 wk with and without one-half of the added fine granular limestone substituted for oyster shell. No correction for Na was made. A dietary calcium concentration of 2.75% was used in Experiment 1 and 3.5% in Experiment 2. Egg specific gravity, egg production, feed consumption, and egg weight were measured. Sodium zeolite A increased egg specific gravity, and the beneficial effects of ZA were maintained during Weeks 5 and 6 when pullet-sized limestone was added to the control diet containing no ZA (Experiment 1). Oyster shell and ZA improved egg specific gravity in Experiment 2 and the effect was additive. Dietary treatments had no effect on egg production or egg weight in Experiments 1 or 2 and there was no effect on feed consumption (Experiment 1). Feed consumption was reduced by ZA, when hens were fed oyster shell, but not when they were fed ZA with fine granular limestone (Experiment 2). It was concluded that the beneficial effect of ZA on egg specific gravity was independent of particle size of CaCO3 in the diet.

A critical evaluation of commercial urodynamics systems

A comprehensive protocol was developed for assessing urodynamics instrumentation and applied to eight commercial urodynamics systems obtained on short-term loan. Assessment covered the areas of design and construction, measurement accuracy, and software performance. The measurement performance of virtually all systems was found to be adequate for the application. The main areas of weakness were susceptibility to artefact, poor user-friendliness, and lack of physical ruggedness.

A consumer's guide to commercially available urodynamic equipment

Eight commercially available urodynamic machines from 6 major manufacturers (Aspen Medical, Dantec, Electro-Medical Supplies (EMS), Uro-gyn, Ormed and Wiest) were assessed for accuracy, construction and user-friendliness. There was less than 10% inaccuracy with regard to fill volume, void rate and pressure measurements. The Wiest 6000 plus system was between 11 and 14% inaccurate during voided volume measurement and other systems were less than 10% inaccurate. User-friendliness was assessed during routine cystometry and is mainly dependent on the software supplied with the equipment. The merits and faults of each urodynamic system with regard to performing a urodynamic investigation, running a urodynamic service and data management are compared with an "ideal" urodynamic system.

Influence of sodium aluminosilicate, hydroxy-sodalite, carnegieite, aluminum sulfate, and aluminum phosphate on performance of commercial Leghorns

Experiments were conducted to determine if the high ion-exchange capacity of sodium aluminosilicate (ZA) marketed as ETHACAL Feed Component or its aluminum content or both are related to the beneficial effect of ZA on egg specific gravity (ESG). In Experiments 1 and 2, ZA was compared with hydroxy-sodalite (HS) and carnegieite, which have the same chemical formula as ZA but little or no ion-exchange capacity. Two levels of ZA (0 and 1.5% of the diet) and three levels of HS (0, .75, and 1.5%) were fed in Experiment 1. In Experiment 2, 0, .75, and 1.5% of ZA and carnegieite were fed. In Experiment 3, ZA, carnegieite, aluminum sulfate, and aluminum phosphate were fed at levels calculated to contain .148 and .101% aluminum. Criteria evaluated were ESG, egg production, feed consumption, and egg weight. Egg specific gravity was significantly improved by ZA in all experiments and was not affected by HS, carnegieite (Experiments 1 and 2), aluminum sulfate (.148% Al), or aluminum phosphate (Experiment 3). Carnegieite and aluminum (.101%) from aluminum sulfate increased ESG in Experiment 3. In Experiments 1 and 3, egg production and feed consumption were not influenced by various treatments. Carnegieite and ZA reduced egg production and feed consumption in Experiment 2. It was concluded that the ion-exchange capacity and aluminum content of ZA may contribute to its beneficial effect on ESG.

Response of commercial Leghorns to sodium aluminosilicate when fed different levels and sources of available phosphorus

Two experiments were conducted to elucidate possible explanations for the adverse interaction of sodium aluminosilicate (ZA) and low phosphorus on egg production. In Experiment 1, hens were fed available phosphorus at two levels (.40 and .31%) and from three sources (dicalcium phosphate, defluorinated phosphate, and meat and bone meal). Two levels (0 and .75%) of ZA were concomitantly fed with these treatments. In Experiment 2, hens were fed two levels (.30 and .20%) and two sources (dicalcium phosphate and defluorinated phosphate) of phosphorus with and without ZA (0 and .75%). In both experiments, egg production, egg specific gravity, feed consumption, and egg weight were measured. In Experiment 2, plasma sodium, potassium, chloride, total and free calcium, and phosphorus were also monitored. Results of both Experiments indicated that ZA significantly increased egg specific gravity; whereas, phosphorus level and source had no effect on egg specific gravity. Egg production was influenced by ZA level, phosphorus source, and phosphorus level with significant phosphorus source by phosphorus level interactions. In Experiment 1, ZA reduced egg production at the higher phosphorus level when dicalcium phosphate or defluorinated phosphate was used but not at the lower phosphorus level. Egg production was not influenced by ZA when meat and bone meal was the source of phosphorus. In Experiment 2, ZA reduced egg production more at the lowest level of phosphorus and more when the phosphorus source was defluorinated phosphate than when it was dicalcium phosphate but the interaction was not significant. Sodium aluminosilicate had no influence on egg weight, but it did reduce feed consumption.(ABSTRACT TRUNCATED AT 250 WORDS)

Impact of diagnosis-related groups on the quality of postoperative care of patients with neck dissections

Two hundred eighty patients underwent neck dissection over a 10-year period: 138 during the 5-year period before the institution of Diagnosis-Related Group (DRG) reimbursement and 142 during the 5 years after DRG regulations. A comparison of these two groups by site of tumor, stage of disease, histopathology, previous treatment, type of neck dissection, whether neck dissection was carried out alone or in combination with another procedure, presence of preexisting disease, postoperative complications, and mortality revealed no significant differences. A 35% reduction in the length of hospital stay from 16 to 10 days was identified in the post-DRG group with no detrimental effects on patient care. The variables found to have the greatest impact on length of hospital stay were the extent of operation and postoperative complications.

The duplex ureter in Burnley, Pendle and Rossendale

Following the report of an unusually high number of patients presenting with duplex ureter in the Dorchester area, we reviewed the incidence of duplex ureter in the Burnley, Pendle and Rossendale district. Based on a review of intravenous urograms, the prevalence was found to be 3.7% (16 of 432). This confirmed the authors' clinical impression that the incidence was higher than previously quoted figures.

Reference dose (RfD): description and use in health risk assessments

For many years the concept of the "acceptable daily intake" has served the toxicological and regulatory fields quite well. However, as approaches to assessing the health significance of exposures to noncarcinogenic substances receive greater scrutiny, some difficulties with this traditional approach have become more apparent. Consequently, the concept of the "reference dose" is introduced in order to avoid use of prejudicial terms (e.g., "safety" and "acceptable"), to promote greater consistency in the assessment of noncarcinogenic chemicals, and to maintain the functional separation between risk assessment and risk management.

Health hazard assessment for chlorinated dioxins and dibenzofurans other than 2, 3, 7, 8-TCDD

EPA is faced with the need to perform health risk assessments of environmental materials containing mixtures of chlorinated dioxins and -dibenzofurans. Preferably, such an assessment must be based on the direct evaluation of chronic health effects of the mixture or on a knowledge of the toxic effects of each of the components. In the absence of such data, the authors have developed two pragmatic approaches that can reasonably be applied to mixtures such as flyash or contaminated soil. The details of these approaches, viewed as interim procedures, are compared and contrasted with those used by other regulatory and public health authorities.

Porcine and human insulin (Novo): a comparison of their metabolism and hypoglycemic activity in normal man

The total body metabolic clearance rates (MCR), plasma half disappearance times (T 1/2), apparent distribution volumes (DS), and effect on plasma glucose concentration of porcine and human insulin (Novo) were compared in six normal subjects. A priming-dose continuous infusion protocol was used. Blood glucose concentration was allowed to fall unchecked. Metabolic clearance rates were studied at four different serum insulin concentrations spanning the physiologic range. In none of the variables studied were we able to demonstrate a significant difference between porcine and human insulin.