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At least 163 records · Page 9Linked to original sources
PubMed1989

Influence of time intervals on outcome of CPR. The Cerebral Resuscitation Study Group.

Time is an essential element for successful CPR. Two time factors are particularly important: the duration of complete CA and the time to advanced life support. According to a registration protocol, these time factors, together with other variables and outcome were recorded in 3083 CA cases, treated by the NICU teams of 7 major Belgian hospitals. The mean duration of complete CA is 10.3 min for CPR failure (79%); 5.3 min for initial CPR success (21%); 3.4 min for long-term CPCR success (7%). The mean time to ALS is 19.7 min for CPR failure; 14.6 min for initial CPR success: 12.7 min for long-term CPCR success. Both duration of CA and time to ALS are independently related to outcome; the mean duration of BLS is less than 10 min and not significantly related to outcome. Response time of BLS and ALS are increasingly important in their 'rapid response' failure zone (time to ALS more than 8 min, time to BLS more than 4 min). The tiered MICU system, with nurse paramedics before physicians, has equal time to ALS and comparable outcome results to the non-tiered MICU system. According to our present experience, the following time goals are proposed for Belgian EMS-MICU systems: duration of CA less or equal to 4 min (introduction time less than or equal to 1 min and response time of BLS less than or equal to 3 min) and time to ALS less than or equal to 9 min. These time goals stand, in Belgium for perfection of public training in CPR and for spreading of a higher number of MICU teams countrywide.

Allied Health Personnel↗
PubMed1989

Influence of pre-CPR conditions on EMS response times in circulatory arrest. The Cerebral Resuscitation Study Group.

Several time intervals, with important influence on the outcome of CA and CPR, are determined by the local EMS-MICU characteristics: time to introduction in the EMS, response time of BLS, duration of BLS before ALS. These time factors have been studied in 2779 out-of-hospital CA cases, treated by the MICU in teams of 7 major Belgian hospitals. The analysis compares the time intervals in the following pre-CPR conditions: the age of the patient; the previous health status of the patient; the disease underlying the CA; the site where CA occurs; the witnessing of the CA; the type of CA; the MICU center, responding to the CA. The mean introduction time is 4.6 min, the mean response time of BLS is 5.1 min, the mean duration of BLS before ALS is 11 min. Introduction in EMS should be improved in CA due to intoxication, drowning, SIDS and respiratory disease, and overall when CA occurs at home.

Ambulances↗
PubMed1989

Initiation of closed-chest cardiopulmonary resuscitation basic life support. A personal history.

Modern external (closed-chest) cardiopulmonary resuscitation (CPR) basic life support (BLS) gives everyone anywhere a chance to initiate the reversal of death from airway obstruction, apnea, or pulselessness. The history of modern CPR has its roots around 1900, but lay dormant for half a century, until in the 1950s several fortunate circumstances merged to allow for documentation of Steps A (airway control by head-tilt and jaw-thrust), B (breathing control by mouth-to-mouth ventilation), and C (circulation control by closed-chest cardiac massage, i.e. chest compressions) and their combination into BLS Steps A-B-C. BLS is only for borderline emergency oxygenation, i.e. Phase I of the life support chain. Both the non-authoritarian environment of the U.S.A. and several role players with keen interest in resuscitation were needed to enable the systematic research (Steps A and B), a chance rediscovery (Step C), and the integration of BLS with advanced life support (ALS, drugs and defibrillation, transferred from open-chest CPR) and brain-oriented prolonged life support (PLS, intensive care) to result in the development of an effective cardiopulmonary-cerebral resuscitation system. A fertile environment led rapidly to the development of resuscitation delivery systems in hospitals and communities. This paper is a story told by one of the role players.

History, 20th Century↗
PubMed1990

Cloning and characterization of the gene encoding a blasticidin S acetyltransferase from Streptoverticillum sp.

A gene (bls) encoding a blasticidin S-acetyltransferase from Streptoverticillum sp. JCM4673 was cloned in the Streptomyces plasmid pIJ702 and expressed in S. lividans 1326. Four of the recombinant plasmids contained a common 1129-bp BclI-PstI DNA fragment, which by subcloning experiments was shown to carry the bls gene. Sequencing of the 1129-bp BclI-PstI fragment indicated that it contains two open reading frames of 408 and 366 nucleotides (nt), both starting with ATG and terminating at TGA triplets. Deletion analysis showed that the correct bls sequence is that of 408 nt, whose deduced amino acid sequence conforms to a polypeptide of Mr 15073. A 175-bp DNA fragment from the 5' region of the bls gene had promoter activity in the promoter-probe plasmid pIJ486.

Acetyltransferases↗
PubMed2005

Comparison of termination-of-resuscitation guidelines for basic life support: defibrillator providers in out-of-hospital cardiac arrest.

STUDY OBJECTIVE: Termination of resuscitation in the field for out-of-hospital cardiac arrest can reduce unnecessary transport to hospital and associated road hazards and increase availability of emergency medical services (EMS) and emergency department resources for other patients. We compare the performance of 3 termination-of-resuscitation guidelines for basic life support-defibrillator (BLS) providers when applied to cardiac arrest patients in the Ontario Prehospital Advanced Life Support study. METHODS: This prospective cohort study involved all out-of-hospital cardiac arrest patients attended by BLS defibrillator providers in 21 Ontario urban or suburban communities. The data analyses were conducted secondarily on these prospectively collected data. Three termination-of-resuscitation guidelines (referred to as Marsden, Petrie, and Verbeek rules) were applied and contingency tables calculated to show the relationship between the rule and actual survival. RESULTS: From 1988 to 2003, 13,684 cardiac arrest patients were attended by BLS defibrillator providers. Six hundred thirty-six (4.7%) patients survived to hospital discharge. For the 3 termination-of-resuscitation rules, sensitivity was 99.8% (95% confidence interval [CI] 99.5% to 100.0%) (Petrie rules), 99.5% (95% CI 99.0% to 100.0%) (Verbeek rules), and 99.8% (95% CI 99.5% to 100.0%) (Marsden rules). Specificity was 9.9% (95% CI 9.4% to 10.4%) (Petrie rules), 52.9% (95% CI 52.1% to 53.8%) (Verbeek rules), and 19.4 % (95% CI 18.8% to 20.1%) (Marsden rules). Negative predictive value was 99.9% (95% CI 99.8% to 100.0%) (Petrie rules), 100.0% (95% CI 99.9% to 100.0%) (Verbeek rules), and 100.0% (95% CI 99.9% to 100.0%) (Marsden rules). These rules would have resulted in field termination of resuscitation in 9.4% (Petrie rules), 50.5% (Verbeek rules), and 18.5 % (Marsden rules) of cases. Termination of resuscitation was recommended for 1 patient (Petrie rules), 3 patients (Verbeek rules), and 1 patient (Marsden rules), who survived. CONCLUSION: We found all 3 termination-of-resuscitation rules to have high sensitivity and negative predictive value. However, the specificity and transport rates varied greatly. The results of this study will be useful for EMS providers considering adoption of termination of resuscitation in BLS defibrillator systems for out-of-hospital cardiac arrest.

Adolescent↗
PubMed2005

Influence of bacteriocin-like substance, generation times, and genetic profiles of Listeria innocua on the isolation of Listeria monocytogenes.

Inhibition of isolation of Listeria monocytogenes by bacteriocin-like substance (BLS)-producing Listeria innocua after enrichment culture was investigated. When 26 L. monocytogenes strains were examined in combination with eight L. innocua strains using the spot on lawn method, 52/208 (25.0%) combinations showed the growth inhibition of L. monocytogenes. When two Listeria species were cultured simultaneously in selective enrichment broth, inhibition of isolation of L. monocytogenes was observed in 12/52 of the combinations at 24h (23.1%), in 24/52 at 48h (46.2%) and in 30/52 (57.7%) after 7 days of incubation. The randomly amplified polymorphic DNA profiles showed no interstrain similarities between either strains of the BLS-producing L. innocua or the BLS-sensitive L. monocytogenes strains. Therefore inhibition by BLS-producing L. innocua of isolation of L. monocytogenes after enrichment culture is unlikely to be dependent upon a particular genetic profile.

Bacteriocins↗
PubMed2006

Online resuscitation training. Does it improve high school students' ability to perform cardiopulmonary resuscitation in a simulated environment?

There are no published data on the efficacy of online first aid or resuscitation learning programmes in Australia. Our goal was to compare the knowledge and first aid skills of subjects who have undertaken the St. John Ambulance Australia (WA) "online crash course", with those who have no first aid training. We evaluated first aid knowledge and basic life support (BLS) skills of two groups of students. The control group (n = 11) had received no first aid training of any type and the test group (n = 12) had undertaken and passed the St. John Ambulance online "crash course". This course is purely theoretical. BLS skills were assessed using standardised patients and manikins. Knowledge was assessed by a written assessment. Assessors were blinded to which group the students belonged. There were significant differences in the performance of the written test, between the group who completed the course and the group who did not complete the course (P = 0.036: Mann-Whitney U-test). There were no significant differences in the performance of any other practical tasks between the two groups. We conclude from this that the online course improved course participant's knowledge of BLS significantly, but not their ability to perform; that online first aid courses may be useful for knowledge acquisition but that they do not confer any benefit, in performance of BLS skills.

Adolescent↗
PubMed1992

Behavior of axons, Schwann cells and perineurial cells in nerve regeneration within transplanted nerve grafts: effects of anti-laminin and anti-fibronectin antisera.

Wistar rats (close cloned strain) were used to investigate the effect of endogenous laminin and fibronectin on axons, Schwann cells and perineurial cells in the regenerating peripheral nervous system (PNS). Sciatic nerve grafts obtained from donor rats were frozen, thawed and treated with rabbit anti-rat laminin or anti-fibronectin antiserum. Control grafts were treated with normal rabbit serum alone. One cm long portions of the sciatic nerve of the recipient rats were replaced with grafts. At 15 days after transplantation the number of regenerated axons in the laminin- and fibronectin-depleted grafts was half of that in the control. The growing axons in the laminin-depleted grafts did not recognize the basal lamina scaffolds (BLS) remaining in the basal lamina tubes, while in the control and fibronectin-depleted grafts 90% or more of axons grew inside the BLS. Elongation of axons always preceded migration of Schwann cells with the latter subsequently adhering to and wrapping around the former. Perineurium-forming fibroblastic cells recognized the combination of axons and Schwann cells and formed perineurial fasciculi around them. These fibroblastic cells did not recognize empty BLS but responded to them only when fibronectin was depleted. Macrophages sometimes closely faced the naked axons which elongated outside the BLS. These results suggest that in the early stages of nerve regeneration endogenous laminin and fibronectin not only regulate the growth of regenerating nerve fibers, but also exert a positive influence on perineurial cells and macrophages, both of which play important roles in nerve tissue injury and repair.

Animals↗
PubMed1993

Emergency medical services priority dispatch.

STUDY OBJECTIVE: To test the ability of a locally designed priority dispatch system to safely exclude the need for advanced life support (ALS). DESIGN: Retrospective review of emergency medical services (EMS) incident records to determine how often the lone dispatch of basic life support (BLS) units, staffed with basic emergency medical technicians, subsequently required or involved ALS care. SETTING: A large centralized municipal EMS system with a tiered ALS/BLS ambulance response. All BLS units carry automated defibrillators. MEASUREMENTS: Consecutive EMS records (35,075) were reviewed by computerized search for ALS procedures. Records indicating ALS procedures were tabulated and then manually reviewed for the nature of and probable indication for the ALS intervention. INTERVENTION: Brief sequences of computer-stored questions that help dispatchers identify (or exclude) signs and symptoms indicating the need for ALS. RESULTS: The dispatch triage system spared ALS units from initial dispatch in 14,100 of the EMS incidents (40.2%), increasing their availability and use for more serious calls. Among these 14,100 cases, only 41 patients (0.3%) later received drugs such as nitroglycerin and naloxone; another 27 patients (0.2%) received resuscitative interventions such as epinephrine or defibrillation. Furthermore, on closer analysis, the immediate presence of a paramedic might have provided a true potential for advantage in outcome for only five or six patients (less than 0.04 of the 14,100 BLS dispatches). Meanwhile, many important operational, fiscal, and cost-effective patient care benefits were realized with this system. CONCLUSION: A computer-aided dispatch triage algorithm can facilitate improvements in both EMS system operations and prehospital patient care by safely and reliably identifying EMS incidents requiring only BLS.

Algorithms↗
PubMed1990

Characteristics of midsized urban EMS systems.

Emergency medical services (EMS) systems in 25 midsized cities (population, 400,000 to 900,000) are described. Information describing EMS system configuration and performance was collected by written and telephone surveys with follow-ups. Responding cities provide either one- or two-tier systems. In a one-tier system, an advanced life support (ALS) unit responds to and transports all patients who use 911 to activate the system. Three types of two-tier systems are identified. In system A, ALS units respond to all calls. Once on scene, an ALS unit can turn a patient over to a basic life support (BLS) unit for transport. In system B, ALS units do not respond to all calls; BLS units may be sent for noncritical calls. In system C, a nontransport ALS unit is dispatched with a transporting BLS unit. For ALS calls, ALS personnel join BLS personnel for transport. Overall, cities staff an average of one ambulance per 51,223 population. One-tier systems average one ambulance per 53,291 compared with two-tier systems, which average one ambulance per 47,546. In the two-tiered system B, the average ALS unit serves 118,956 population. In the 60% of cities that use a one-tier system, one ALS unit serves 58,336 (P less than .0005). Overall, the code 3 response time for all cities is an average of 6.6 minutes. The average response time of two-tier systems is 5.9 minutes versus 7.0 minutes for one-tier systems (.05 less than P less than .1). These data suggest that the two-tiered system B allows for a given number of ALS units to serve a much larger population while maintaining a rapid code 3 response time.

Ambulances↗
PubMed1988

A controlled trial of prehospital advanced life support in trauma.

We compared the outcome of 472 trauma patients who required ambulance attention and who received prehospital advanced life support (ALS) with another similar 589 patients who received only basic life support (BLS). Nontrapped, critically injured ALS patients were treated for an average of 13 minutes at the scene of injury, compared with 17 minutes for BLS cases (P less than .05). Seventeen of 37 ALS deaths (36%) occurred within 24 hours of injury, compared with 24 of 33 BLS fatalities (73%) (P less than .05). However, the overall case fatality rate was similar in the two groups, and regression analyses did not demonstrate an impact of ALS care on mortality. ALS resuscitation did not reduce the duration of hospital or intensive care unit stay, or the incidence of disability after head injury. However, the incidence of respiratory failure in the critically injured patients was 5% (ALS) and 19% (BLS) (P less than .025). ALS care appeared to influence patient outcome during the first 24 hours after injury, but had little impact on the later clinical course. Our sample size was too small to rule out any effect of ALS on in-hospital mortality. However, the improved 24-hour survival associated with ALS care suggests some benefit of prehospital resuscitation in major trauma.

Adult↗
PubMed1996

Basic life support skill acquisition and retention in student nurses undertaking a pre-registration diploma in higher education/nursing course.

Many studies have investigated the ability of health care professionals to provide competent Basic Life Support (BLS) and all results indicate that the majority of staff fail to demonstrate competence. However, it has not yet been shown whether this poor performance is due to deterioration of skill or the nonacquisition of the skill during BLS training. This study seeks to identify aspects of BLS acquisition and retention by student nurses during their three years of training. The two issues under consideration are the effect of teacher-student ratio and the effect of regular practice on BLS performance. This paper provides a review of the methodology and the initial findings.

Cardiopulmonary Resuscitation↗
PubMed1996

Pattern of basic life support ambulance use in an urban pediatric population.

To evaluate the pattern of use of basic life support (BLS) ambulances in a pediatric population, emergency medical service (EMS) and pediatric emergency department (PED) records from an urban hospital PED for all children transported to PED by ambulance during a 1-month study period were retrospectively reviewed. Excluded were: (1) advanced life support transport, (2) transport from other medical facility, (3) patients with chronic medical disability without acute decompensation, and (4) patients in police custody. BLS transport was considered inappropriate if: (1) no intervention by BLS technicians, (2) minimal to no intervention in the PED, and (3) discharge without prescription medication. Of 376 ambulance transports evaluated, 238 (63%) met entry criteria, and 105 (44%) transports met criteria for being inappropriate. The mean charge for appropriate transport was $240.68, and for inappropriate, $237.12 (P = .2). The total charge for inappropriate transports was $26,523.20. Patients on federal assistance had a significantly higher rate of inappropriate transport (51%) compared with patients who had commercial insurance (30%) and those who self paid (42%). Trauma was the most common cause for transport, 48% of which was inappropriate. It was concluded that inappropriate BLS transport of pediatric patients is common. This use is costly and may disrupt the delivery of EMS care to the remainder of the community. Efforts aimed at public education and providing alternative means of transport may significantly reduce charges and improve the delivery of EMS care.

Ambulances↗
PubMed1999

RFX-B is the gene responsible for the most common cause of the bare lymphocyte syndrome, an MHC class II immunodeficiency.

The bare lymphocyte syndrome (BLS) is characterized by the absence of MHC class II transcription and humoral- and cellular-mediated immune responses to foreign antigens. Three of the four BLS genetic complementation groups have defects in the activity of the MHC class II transcription factor RFX. We have purified the RFX complex and sequenced its three subunits. The sequence of the smallest subunit describes a novel gene, termed RFX-B. RFX-B complements the predominant BLS complementation group (group B) and was found to be mutant in cell lines from this BLS group. The protein has no known DNA-binding domain but does contain three ankyrin repeats that are likely to be important in protein-protein interactions.

Amino Acid Sequence↗
PubMed2003

T cell leukemia I oncogene expression depends on the presence of Epstein-Barr virus in the virus-carrying Burkitt lymphoma lines.

We used a modified subtractive suppression hybridization to identify cellular genes that show altered expression in Burkitt lymphomas (BLs) in the presence of Epstein-Barr virus (EBV). Comparison of the gene expression patterns of an EBV-negative clone of the originally EBV-positive BL line Akata, with its Neo(R)-EBV derivative, revealed a significant difference in the expression of the T cell leukemia 1 oncogene (TCL-1). Subsequent expression studies showed that the original EBV-positive Akata line and the EBV-reconstituted derivative expressed high levels of TCL-1, whereas the EBV-negative variant showed only a low level of expression. Two other independently established EBV-positive BLs (Mutu and OMA) that have also thrown off EBV showed a similar decrease in TCL-1 expression after virus loss. Reinfection with Neo(R)-EBV restored the TCL-1 expression levels in the EBV loss variants to as high a level as the originally EBV-positive lines. High-resolution immunostaining showed that TCL-1 was localized in both the cytoplasm and the nucleus. Our findings suggest that high expression of TCL-1 is necessary for the development of the BL phenotype. In view of the fact that germinal center B cells, regarded as the progenitors of BL, do not express TCL-1, we suggest that constitutive expression of this oncogene occurs by genetic or epigenetic changes in the EBV-negative BLs. In the originally EBV-positive BLs, the ability of the virus to switch on TCL-1 expression would obviate this need.

Base Sequence↗
PubMedDate not supplied

Cost-effectiveness analysis of a rural/urban first-responder defibrillation program.

OBJECTIVE: To analyze the cost-effectiveness of a proposed first-responder defibrillation program in a small rural area in comparison with a recently initiated first-responder program in an adjoining urban center in southwestern Ontario. The purpose of the analysis was to quantify the expected benefits of the proposed program to determine whether the costs are justified. METHODS: This analysis was conducted on the city of Waterloo (population 80,000 over 25 square miles) and the adjoining rural township of Wellesley (population 8,000 over 105 square miles). The township has volunteer fire department first responders with basic life support (BLS), and basic life support/defibrillation (BLS-D) ambulances as the second tier; whereas the city's full-time fire department has recently adopted a first-responder defibrillation (BLS-D) program backed up by the same BLS-D ambulance service. The most relevant costs identified were the capital costs of the defibrillators, ancillary equipment, and biomedical service for preventive maintenance and routine nonwarranty work. Response intervals and percentage of patients found in ventricular fibrillation were projected and sensitivity analysis was applied. RESULTS: The projected cost per life saved is $6,776 (C) in the urban area and $49,274 (C) in the rural area using an incremental save rate of 6%. Applying sensitivity analysis to the data, the save rate varied from 2% to 10%, resulting in a cost per life saved of $20,328 (C) and $4,066 (C), respectively, in the urban community. For the rural area, the cost per life saved ranged from $147,821 (C) (2%) to $29,564 (C) (10%). Even the worst-case save rate for the urban center [2%; $20,328 (C)] is significantly less than the best-case save rate [10%; $29,564 (C)] for the rural area. CONCLUSIONS: The cost per life saved for a rural first-responder defibrillation program is significantly more expensive than one for an urban center. However, the cost per life saved is still economical compared with common treatments for other life-threatening illnesses.

Cost-Benefit Analysis↗
PubMedDate not supplied

Is there a role for first responders in EMS responses to medical facilities?

OBJECTIVE: Emergency medical dispatch (EMD) protocols should match response resources with patient needs. We tested a protocol sending only a commercial ambulance, without fire department first responders (FR), to all non-cardiac-arrest EMS calls at a physician-staffed HMO facility. Study objectives were to determine how often FR provided patient care at such facilities and whether EMD implementation could conserve FR resources without compromising patient care. METHODS: All EMS dispatches to this facility in the 4 months before implementation of the EMD protocol and 4 months after implementation were identified through dispatch records, and all FR and ambulance patient care reports were reviewed. In the "after" phase, all cases needing ALS transport were reviewed to examine whether there would have been benefit to FR dispatch. RESULTS: Of 242 dispatches in the "before" phase, BLS FR responded to 156 (64%), and ALS FR to 117 (48%). BLS FR provided patient care in 2 cases, and ALS FR in 17. Of 227 dispatches in the "after" phase, BLS FR responded to 10 (4%), and ALS FR to 10 (4%); all but one were protocol violations. BLS FR provided care in one case, and ALS FR in three. Review of the 93 "after" cases requiring ALS transport found none where FR presence would have been beneficial. CONCLUSIONS: First responders rarely provided patient care when responding to EMS calls at a physician-staffed medical facility. Implementation of an EMD protocol can safely reduce the number of FR responses to unscheduled ambulance calls at such a facility.

Advanced Cardiac Life Support↗
PubMed2002

Groundwater contamination downstream of a contaminant penetration site. II. Horizontal penetration of the contaminant plume.

Part I of this study (Rubin, H.; Buddemeier, R.W. Groundwater Contamination Downstream of a Contaminant Penetration Site Part 1: Extension-Expansion of the Contaminant Plume. J. of Environmental Science and Health Part A (in press).) addressed cases, in which a comparatively thin contaminated region represented by boundary layers (BLs) developed within the freshwater aquifer close to contaminant penetration site. However, at some distance downstream from the penetration site, the top of the contaminant plume reaches the top or bottom of the aquifer. This is the location of the "attachment point," which comprises the entrance cross section of the domain evaluated by the present part of the study. It is shown that downstream from the entrance cross section, a set of two BLs develop in the aquifer, termed inner and outer BLs. It is assumed that the evaluated domain, in which the contaminant distribution gradually becomes uniform, can be divided into two sections, designated: (a) the restructuring section, and (b) the establishment section. In the restructuring section, the vertical concentration gradient leads to expansion of the inner BL at the expense of the outer BL, and there is almost no transfer of contaminant mass between the two layers. In the establishment section, each of the BLs occupies half of the aquifer thickness, and the vertical concentration gradient leads to transfer of contaminant mass from the inner to the outer BL. By use of BL approximations, changes of salinity distribution in the aquifer are calculated and evaluated. The establishment section ends at the uniformity point, downstream from which the contaminant concentration profile is practically uniform. The length of the restructuring section, as well as that of the establishment section, is approximately proportional to the aquifer thickness squared, and is inversely proportional to the transverse dispersivity. The study provides a convenient set of definitions and terminology that are helpful in visualizing the gradual development of uniform contaminant concentration distribution in an aquifer subject to contaminant plume penetration. The method developed in this study can be applied to a variety of problems associated with groundwater quality, such as initial evaluation of field data, design of field data collection, the identification of appropriate boundary conditions for numerical models, selection of appropriate numerical modeling approaches, interpretation and evaluation of field monitoring results, etc.

Environmental Monitoring↗