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Biomedical subjects

Charles Maynard

Publications and source records attributed to Charles Maynard.

At least 19 recordsLinked to original sources
PubMed2006

The value of both ST-segment and QRS complex changes during acute coronary occlusion for prediction of reperfusion-induced myocardial salvage in a canine model.

BACKGROUND: Analysis of ST-segment elevation for assessment of patients with suspected acute coronary occlusion is in widespread use for diagnostic and prognostic purposes. In this study, changes in the QRS complex also were analyzed to determine if these changes that are seldom used clinically can provide additional prognostic information. An acute coronary occlusion canine model, in which direct measurements of myocardial salvage were made, was used to assess whether ST-segment and QRS complex changes during coronary occlusion yielded independent estimates of the amount of salvage provided by reperfusion with arterial blood. METHODS AND RESULTS: Continuous electrocardiographic recordings were obtained from 14 study dogs undergoing a 90-minute period of coronary artery occlusion in which the severity of the ischemia during the occlusion was estimated at 10 and 45 minutes by microsphere injections. After 3 hours of reperfusion, the myocardium at risk and postmortem infarct size was measured. Myocardial salvage correlated inversely with both ST-segment elevation (r = -0.85; P < .0001), and QRS complex prolongation (r = -0.72; P = .003). When dogs were paired so that they had equal amounts of ST elevation but differed with respect to the presence of QRS prolongation, less myocardial salvage was found in those with QRS prolongation. The independent value of QRS prolongation was supported further by the observation that presence of QRS prolongation resulted in a loss of the highly significant correlation between ST elevation and salvage (r = -0.60; P = .2). CONCLUSIONS: High magnitudes of ST elevation are correlated significantly with less myocardial salvage. Moreover, for a given magnitude of ST elevation, the presence of concurrent QRS prolongation is associated with even less myocardial salvage.

Animals↗
PubMed2006

Transthoracic incremental monophasic versus biphasic defibrillation by emergency responders (TIMBER): a randomized comparison of monophasic with biphasic waveform ascending energy defibrillation for the resuscitation of out-of-hospital cardiac arrest due to ventricular fibrillation.

BACKGROUND: Although biphasic, as compared with monophasic, waveform defibrillation for cardiac arrest is increasing in use and popularity, whether it is truly a more lifesaving waveform is unproven. METHODS AND RESULTS: Consecutive adults with nontraumatic out-of-hospital ventricular fibrillation cardiac arrest were randomly allocated to defibrillation according to the waveform from automated external defibrillators administered by prehospital medical providers. The primary event of interest was admission alive to the hospital. Secondary events included return of rhythm and circulation, survival, and neurological outcome. Providers were blinded to automated defibrillator waveform. Of 168 randomized patients, 80 (48%) and 68 (40%) consistently received only monophasic or biphasic waveform shocks, respectively, throughout resuscitation. The prevalence of ventricular fibrillation, asystole, or organized rhythms at 5, 10, or 20 seconds after each shock did not differ significantly between treatment groups. The proportion of patients admitted alive to the hospital was relatively high: 73% in monophasic and 76% in biphasic treatment groups (P=0.58). Several favorable trends were consistently associated with receipt of biphasic waveform shock, none of which reached statistical significance. Notably, 27 of 80 monophasic shock recipients (34%), compared with 28 of 68 biphasic shock recipients (41%), survived (P=0.35). Neurological outcome was similar in both treatment groups (P=0.4). Earlier administration of shock did not significantly alter the performance of one waveform relative to the other, nor did shock waveform predict any clinical outcome after multivariate adjustment. CONCLUSIONS: No statistically significant differences in outcome could be ascribed to use of one waveform over another when out-of-hospital ventricular fibrillation was treated.

Adult↗
PubMed2006

Effectiveness of prehospital wireless transmission of electrocardiograms to a cardiologist via hand-held device for patients with acute myocardial infarction (from the Timely Intervention in Myocardial Emergency, NorthEast Experience [TIME-NE]).

Percutaneous coronary intervention for patients with ST-segment elevation myocardial infarction (STEMI) decreases morbidity and mortality if performed within the first 2 hours of symptom onset. However, the American College of Cardiology/American Heart Association guideline for percutaneous coronary intervention door-to-balloon time (<90 minutes) in patients with STEMI is a infrequently accomplished goal. This study enrolled 277 patients with STEMI who were self-transported or transported by emergency medical services to NorthEast Medical Center for primary percutaneous coronary intervention. This study tested the hypothesis that prehospital wireless transmission of an electrocardiogram to a cardiologist's hand-held device results in shorter emergency department door-to-reperfusion time. A comparison was made between patients whose electrocardiogram was successfully transmitted during the intervention phase with (1) patients transported by the emergency medical services in the preintervention, (2) patients self-transported in the intervention phase, and (3) patients whose wireless transmission failed in the intervention phase. During the preintervention phase (2001 to 2003), 48 patients were enrolled. During the intervention phase (2003 to 2005), the following patients were enrolled: 101 self-transported patients, 24 patients with successful electrocardiographic transmission, and 19 patients for whom transmission failed. The median door-to-reperfusion time for patients with successful electrocardiographic transmission was 50 minutes, which was significantly shorter than a preintervention time of 101 minutes (p <0.0001), an intervention phase self-transport time of 96 minutes (p <0.0001), and a failed transmission time of 78 minutes (p <0.0001). In conclusion, prehospital wireless electrocardiographic transmission to a cardiologist's hand-held device significantly decreased emergency department door-to-reperfusion time, thus achieving the American College of Cardiology/American Heart Association guideline for patients with STEMI.

Aged↗
PubMed2006

The use of percutaneous coronary intervention in black and white veterans with acute myocardial infarction.

BACKGROUND: It is uncertain whether black white differences in the use of percutaneous coronary intervention (PCI) persist in the era of drug eluting stents. The purpose of this study is to determine if black veterans with acute myocardial infarction (AMI) are less likely to receive PCI than their white counterparts. METHODS: This study included 680 black and 3529 white veterans who were admitted to Veterans Health Administration (VHA) medical centers between July 2003 and August 2004. Information for this study was collected as part of the VHA External Peer Review Program for quality monitoring and improvement for a variety of medical conditions and procedures, including AMI. In addition, Department of Veterans Affairs workload files were used to determine PCI utilization after hospital discharge. Standard statistical methods including the Chi-square, 2 sample t-test, and logistic regression with a cluster correction for medical center were used to assess the association between race and the use of PCI < or = 30 days from admission. RESULTS: Black patients were younger, more often had diabetes mellitus, renal disease, or dementia and less often had lipid disorders, previous coronary artery bypass surgery, or chronic obstructive pulmonary disease than their white counterparts. Equal proportions of blacks and whites underwent cardiac catheterization < or = 30 days after admission, but the former were less likely to undergo PCI (32% vs. 40%, p < 0.0001). This difference persisted after multivariate adjustment, although measures of the extent of coronary artery disease were not available. CONCLUSION: Given the equivalent use of cardiac catheterization, it is possible that less extensive or minimal coronary artery disease in black patients could account for the observed difference.

Black or African American↗
PubMed2006

The prevalence and outcomes of in-hospital acute myocardial infarction in the Department of Veterans Affairs Health System.

BACKGROUND: Most studies of the epidemiology and treatment of acute myocardial infarction (AMI) have focused on patients who experienced onset of their symptoms in the community and then presented to the hospital. There are, however, patients whose symptoms of AMI begin after hospitalization for other medical conditions. The purposes of this study were to determine the prevalence of in-hospital AMI in the Veterans Health Administration (VHA) and to compare baseline characteristics, treatments, and outcomes according to whether individuals presented with AMI or had an in-hospital AMI. METHODS: This was a retrospective cohort study of 7054 veterans who were hospitalized for AMI in 127 VHA medical centers between July 2003 and August 2004. The main outcome measure was 30-day mortality. Key covariates included age, body mass index, admission systolic blood pressure, heart rate, previous use of lipid-lowering drugs, elevated admission troponin value, prolonged and/or atypical chest pain on admission, and ST-segment elevation on the initial electrocardiogram. RESULTS: There were 792 patients (11.2%) who had AMI while hospitalized for other medical conditions. These patients differed substantially from those who presented to the hospital with AMI. The odds of 30-day mortality were greater in the in-hospital group (odds ratio, 3.6; 95% confidence interval, 3.1-4.3; P<.001) and remained higher after statistical adjustment (odds ratio, 2.0; 95% confidence interval, 1.7-2.4; P<.001). CONCLUSION: Although most attention has been paid to patients with AMI admitted via the community emergency medical system or through the emergency department, AMI occurring during hospitalization for other medical problems is an important clinical problem.

Age Distribution↗
PubMed2006

Accuracy and completeness of mortality data in the Department of Veterans Affairs.

BACKGROUND: One of the national mortality databases in the U.S. is the Beneficiary Identification and Record Locator Subsystem (BIRLS) Death File that contains death dates of those who have received any benefits from the Department of Veterans Affairs (VA). The completeness of this database was shown to vary widely from cohort to cohort in previous studies. Three other sources of death dates are available in the VA that can complement the BIRLS Death File. The objective of this study is to evaluate the completeness and accuracy of death dates in the four sources available in the VA and to examine whether these four sources can be combined into a database with improved completeness and accuracy. METHODS: A random sample of 3,000 was drawn from 8.3 million veterans who received benefits from the VA between 1997 and 1999 and were alive on January 1, 1999 according to at least one source. Death dates found in BIRLS Death File, Medical SAS Inpatient Datasets, Medicare Vital Status, and Social Security Administration (SSA) Death Master File were compared with dates obtained from the National Death Index. A combined dataset from these sources was also compared with National Death Index dates. RESULTS: Compared with the National Death Index, sensitivity (or the percentage of death dates correctly recorded in a source) was 77.4% for BIRLS Death File, 12.0% for Medical SAS Inpatient Datasets, 83.2% for Medicare Vital Status, and 92.1% for SSA Death Master File. Over 95% of death dates in these sources agreed exactly with dates from the National Death Index. Death dates in the combined dataset demonstrated 98.3% sensitivity and 97.6% exact agreement with dates from the National Death Index. CONCLUSION: The BIRLS Death File is not an adequate source of mortality data for the VA population due to incompleteness. When the four sources of mortality data are carefully combined, the resulting dataset can provide more timely data for death ascertainment than the National Death Index and has comparable accuracy and completeness.

Journal Article↗
PubMed2006

Comparison of ST-segment deviation to scintigraphically quantified myocardial ischemia during acute coronary occlusion induced by percutaneous transluminal coronary angioplasty.

This study compared ST-segment changes during acute coronary artery occlusion with measurements of ischemia by myocardial scintigraphy. Forty patients who were referred for elective prolonged percutaneous transluminal coronary angioplasty underwent 12-lead electrocardiographic recording before the procedure (baseline) and continuously during the entire balloon inflation (occlusion). For each patient, the summed ST-segment deviation was calculated as the maximal absolute difference, elevation or depression, between baseline and occlusion recordings in all 12 leads. Each patient underwent 2 myocardial scintigraphies, 1 with technetium-99m sestamibi injected during the balloon inflation and 1 on the following day as a control study. Ischemia that was induced by balloon occlusion was quantified in terms of extent and severity. Results for the entire study group showed that summed ST deviation correlated with extent (r = 0.59, p < 0.0001) and severity (r = 0.61, p < 0.0001) of ischemia. The location of maximal ST deviation differed for the 3 arteries. For occlusion of the left anterior descending artery, maximal ST deviation was elevated in lead V3. For occlusion of the left circumflex artery, maximal ST deviation was depressed in lead V2. Occlusion of the right coronary artery caused ST elevation in lead III and ST depression in lead V2. In conclusion, this study demonstrated a significant correlation between summed ST deviation and myocardial ischemia during coronary occlusion that is induced by percutaneous transluminal coronary angioplasty.

Acute Disease↗
PubMed2006

Usefulness of quantitative baseline ST-segment elevation for predicting outcomes after primary coronary angioplasty or fibrinolysis (results from the DANAMI-2 trial).

The DANAMI-2 trial showed a 40% decrease in the composite end point with primary coronary angioplasty versus fibrinolysis. This result was primarily driven by a decrease in reinfarction, with no significant difference in mortality or stroke rates. The objective of this study was to determine the prognostic value of the sum ST-segment elevation (SigmaST) on baseline electrocardiography in patients who were randomized to receive primary coronary angioplasty versus fibrinolysis. In the DANAMI-2, 1,450 patients had baseline ST-segment deviation measurements and were assigned to quartiles according to SigmaST: 0 to 6.5, 7.0 to 9.5, 10.0 to 14.5, and 15.0 to 70.5 mm. The composite and component end-point rates at 30 days were determined for each quartile and chi-square for trend statistic was used to compare end-point rates across quartiles of SigmaST. The composite end point occurred more often with increasing SigmaST (p = 0.05). With regard to component end points, only mortality increased significantly with SigmaST (p = 0.03), whereas reinfarction and stroke rates did not. By multivariate analysis, only SigmaST and age were independent predictors of mortality. The relative benefit of primary coronary angioplasty was similar for all SigmaST quartiles. In conclusion, the magnitude of SigmaST correlates with increased mortality at 30 days, thus driving the composite end point rate. Regardless of SigmaST, patients had a lower composite end-point rate with primary coronary angioplasty than with fibrinolysis.

Aged↗
PubMed2006

Diagnostic conclusions from the EASI-derived 12-lead electrocardiogram as compared with the standard 12-lead electrocardiogram in children.

BACKGROUND: Fewer electrodes on more easily located places would facilitate electrocardiogram (ECG) recording. To investigate the possibility of simplifying ECG recording in children, we compared the diagnostic conclusions when interpreting standard versus EASI-derived 12-lead ECGs. Our hypothesis was that the variation of the interpretation of standard versus EASI-derived 12-lead ECGs was not greater than the intrareader variation of the interpretation of standard ECGs. METHODS: The study included 221 children. The 2 lead systems were recorded simultaneously. Two experienced pediatric cardiologists interpreted the ECGs. First, the reader interpreted a set of 221 ECGs with randomly allocated standard and EASI-derived 12-lead ECGs. Next, the reader interpreted the complementary ECG set without having access to the first set. Finally, the reader reinterpreted the standard ECGs from 98 children. RESULTS: The variation of the interpretation of standard versus EASI-derived 12-lead ECGs was only slightly larger than the intrareader variation of the interpretation of standard ECGs. CONCLUSIONS: For most of the electrocardiographic diagnoses, the conclusions from EASI-derived 12-lead ECGs were similar to those from standard ECGs. These findings support the suggestion that the EASI lead system is a potential alternative to the standard ECG in children.

Adolescent↗
PubMed2006

Effects of a statewide physician-led quality-improvement program on the quality of cardiac care.

BACKGROUND: Several states have implemented mandatory public reporting of outcomes of cardiac revascularization procedures. Washington is the first to develop a nonmandatory, physician-led reporting program with public accountability and universal hospital participation. The purpose of this study was to determine whether quality improvement interventions resulted in the correction of data deficiencies and performance outliers for cardiac revascularization procedures. METHODS: From 1999 through 2003, there were 18 hospitals with coronary bypass surgery and interventional cardiology programs and 12 with only the latter. All patients > or =18 years undergoing 24372 isolated coronary bypass surgeries and 59,656 percutaneous coronary interventions were included. After 1999 to 2001 data were analyzed in early 2002, the Clinical Outcomes Assessment Program implemented a 6-step quality-improvement intervention to measure and remeasure data quality, process compliance, and performance. RESULTS: In 2003, 4 of the 18 surgery programs had 1 statistical outlier with respect to 4 performance measures, whereas 2 of 30 coronary intervention programs were mortality outliers. For bypass surgery, all programs maintained full compliance with program standards by adhering to timely and reliable submission of data, developing plans to address performance outliers, and demonstrating that outlier status did not persist from baseline to remeasurement. For coronary interventions, 1 program was a persistent outlier for mortality in 2002 and 2003. CONCLUSIONS: The Clinical Outcomes Assessment Program has successfully monitored cardiac care patterns in Washington State over a 5-year period. Most hospitals that perform coronary revascularization procedures meet acceptable performance standards.

Aged↗
PubMed2006

The failure of years of experience with electrocardiographic transmission from paramedics to the hospital emergency department to reduce the delay from door to primary coronary intervention below the 90-minute threshold during acute myocardial infarction.

INTRODUCTION: Emergency medical services (EMS), hospital emergency departments, and cardiologists have taken steps to reduce time to reperfusion therapy by implementation of aggressive acute myocardial infarction treatment and triage protocols. Data indicate that significant myocardial salvage requires reperfusion within 2 hours, and the current American College of Cardiology guideline is 90 minutes after hospital emergency department admission. MATERIALS AND METHODS: To minimize delays in time to reperfusion in an urban-rural North Carolina County, Guilford County EMS and the Moses Cone Hospital have collaborated to implement transmission of EMS electrocardiographs (ECGs) to the emergency department. The study population included 92 patients who were transported by EMS and received primary coronary intervention during the second, third, and fourth years after initiation of this intervention in 1993. RESULTS: The median time from symptom onset to the initial ECG was 77 minutes. There was an additional 23 minutes between the availability of this ECG and the arrival of the patient at the emergency department. In the first year of the intervention, the time from hospital arrival to percutaneous coronary intervention was 80 minutes. In years 2 through 4, they were 93, 85, and 94 minutes, respectively. In 2003, 10 years after the intervention, the time from hospital arrival to percutaneous coronary intervention was 113 minutes. CONCLUSION: Initial gains in the time from hospital arrival to percutaneous coronary intervention, attributed to acquisition of the ECG in the prehospital setting, were not sustained over 10 years.

Angioplasty, Balloon, Coronary↗
PubMed2006

Effects of abciximab as adjunctive therapy in primary percutaneous coronary intervention patients (results from the DANAMI-2 trial).

INTRODUCTION: Successful reperfusion at the epicardial level is not always accompanied by reperfusion of the microvasculature. Therapies targeted against 'no-flow' are often employed in patients receiving primary percutaneous coronary intervention (pPCI) after acute myocardial infarction. HYPOTHESIS: Abciximab as adjunctive to pPCI will improve ST-segment resolution used as a surrogate for optimal microvascular reperfusion, and improve prognosis. METHODS: In the DANAMI-2 trial 309/790 (39%) patients treated with pPCI received abciximab at physician discretion. SigmaST-segment elevation at baseline, 90 min, 4 h, 12 h, 24 h after pPCI and at discharge was measured and ST-segment resolution grouped as: Complete (> or = 70 %); Partial (> or = 30 to < 70%); No (< 30%). Clinical endpoints were death, re-infarction and disabling stroke. RESULTS: Abciximab prescription varied from 24.4-60.3% in the different hospitals. Patients receiving abciximab had a higher risk profile. ST-segment resolution at 90 min and 24 h was identical in the two groups, but at 4 h and 12 h partial ST-segment resolution was more pronounced in patients receiving abciximab (P = 0.001, P = 0.026). In a multivariate analysis, adjusting for baseline differences abciximab was associated with improved partial ST-segment resolution at 12 h. Patients treated with abciximab had no re-infarction at 30 days (0% versus 2.8%, P = 0.003), but increased disabling stroke rate (2.3% versus 0.4%; P = 0.019) driven by cerebral infarctions, and not intracranial hemorrhage. There were no differences in death rates. CONCLUSIONS: In the DANAMI-2 trial with no age limit, the decreased re-infarction rates in patients receiving abciximab was offset by increased disabling stroke rates. Abciximab in conjunction with pPCI is associated with more pronounced partial ST-segment resolution after 4 h to 12 h suggesting improved microvascular reperfusion.

Abciximab↗
PubMed2006

Posttraumatic stress disorder screening status is associated with increased VA medical and surgical utilization in women.

BACKGROUND: Women with posttraumatic stress disorder (PTSD) report poor health, but associations with health care utilization are understudied. OBJECTIVE: To determine associations between medical/surgical utilization and PTSD in female Veterans Affairs (VA) patients. DESIGN: Prospective comparison of utilization rates between women screening positive or negative for PTSD on a mailed survey. SUBJECTS: Women receiving care at an urban VA medical center between October 1996 and January 2000. MEASUREMENTS: Survey responses, including a validated screen for PTSD (PCL-C), and VA utilization data through September 2002. RESULTS: Two thousand five hundred and seventy-eight (2,578) women (78% of those eligible) completed the PCL-C; 858 (33%) of them screened positive for PTSD (PTSD+). In unadjusted models, PTSD+ women had higher rates of medical/surgical hospitalizations and surgical inpatient procedures. Among women ages 35 to 49, mean days hospitalized/100 patients/year was 43.4 (95% CI 26 to 61) for PTSD+ women versus 17.0 (16 to 18) for PTSD negative (PTSD-) women. More PTSD+ women underwent surgical procedures (P<.001). Mean annual outpatient visits were significantly higher among PTSD+ women, including: emergency department (ED) (1.1 [1.0 to 1.2] vs 0.6 [0.5 to 0.6]), primary care (3.2 [3.0 to 3.4] vs 2.2 [2.1 to 2.3]), medical/surgical subspecialists (2.1 [1.9 to 2.3] vs 1.5 [1.4 to 1.6]), ancillary services (4.1 [3.7 to 4.5] vs 2.4 [2.2 to 2.6]), and diagnostic tests (5.6 [5.1 to 6.1] vs 3.7 [3.4 to 4.0]). In multivariate models adjusted for demographics, smoking, service access, and medical comorbidities, PTSD+ women had greater likelihood of medical/surgical hospitalization (OR=1.37 [1.04 to 1.79]) and of being among the top quartile of patients for visits to the ED, primary care, ancillary services, and diagnostic testing. CONCLUSIONS: Female veterans who screen PTSD+ receive more VA medical/surgical services. Appropriateness of that care deserves further study.

Adult↗
PubMed2005

Problem-based learning of research skills.

PURPOSE: To determine whether a short-term, problem-based educational intervention leads to increased research activity among health care practitioners. SUBJECTS AND METHODS: Participant's success was evaluated as a composite of 2 outcomes. These were (1) reporting results for the project designed during the practicum and (2) conducting subsequent research activities. The study population included 36 clinical research outcomes projects developed by clinical practitioners, postgraduate trainees, and medical students during 6 separate practicums. All project teams received the same educational intervention, an "outcomes research practicum" that was divided into 4 primary learning modules administered over a 1 to 4 month period. Each module included a preparatory videotape lecture, supplemental readings, and a 90-minute interactive laboratory session during which faculty members worked with participants to develop answers to a series of predefined questions relating to the design of clinical outcomes research projects. Follow-up continued for a minimum of 12 months and a maximum of 36 months. RESULTS: Eighty-three percent of project teams completed all 4 practicum modules, and 69% completed one of the study outcomes (50% completed their research project and 47% completing a subsequent research activity). Practitioners were more likely to complete subsequent research activities, whereas trainees were more likely to complete their study project. DISCUSSION: This short-term, problem-based educational intervention was successful in increasing the collective research activities of participants. Further, more rigorous structured research is needed to determine the ultimate impact on practice change and patient outcomes.

Education, Medical, Continuing↗
PubMed2005

Comparison of EASI-derived 12-lead electrocardiograms versus paramedic-acquired 12-lead electrocardiograms using Mason-Likar limb lead configuration in patients with chest pain.

INTRODUCTION: Monitoring or serial 12-lead electrocardiogram (ECG) recordings are the accepted requirement for prehospital data acquisition in patients with chest pain. The purpose of this study was to determine whether waveforms and clinical triage decision are similar in EASI-derived ECGs and paramedic-acquired 12-lead ECGs using Mason-Likar limb lead configuration when compared with standard 12-lead ECGs (stdECG). METHOD: Twenty patients with chest pain had a prehospital 12-lead ECG recorded in the ambulance, and paramedic-applied electrodes retained in place at hospital arrival. An ECG technician applied standard precordial and EASI electrodes in their correct positions. Twelve-lead ECGs were obtained from the paramedic-applied electrodes, using their Mason-Likar limb lead configuration, and derived from the EASI leads for comparison with the stdECG. Three computer-measured QRS-T waveform parameters were considered, and differences in waveform measurement between EASI and stdECG (EASIDeltastdECG) versus differences in waveform measurements between paramedic Mason-Likar and stdECG (PMLDeltastdECG) were calculated. Two physicians determined whether the EASI-derived or the paramedic Mason-Likar ECG contained information that would change their clinical triage decision from that indicated by the stdECG. RESULTS: EASIDeltastdECG and PMLDeltastdECG were identical in 28%, whereas EASIDeltastdECG was more than PMLDeltastdECG in 35%, and PMLDeltastdECG was accurate (both time) than EASIDeltastdECG in 37% (P = .62). The physicians were more likely to change the level of patient care based on the EASI-derived ECGs compared with the paramedic ECGs; however, this difference was not statistically significant (P = .27), but this may only be caused by the small study population. CONCLUSIONS: There are similar differences from stdECG waveforms in EASI-derived ECGs and those acquired via paramedic-applied precordial electrodes using Mason-Likar limb lead configuration. Either method can be used as a substitute for monitoring, but neither should be considered equivalent to the stdECG for diagnostic purposes.

Adult↗
PubMed2005

Comparison of the five-electrode-derived EASI electrocardiogram to the Mason Likar electrocardiogram in the prehospital setting.

This study compared the 5-electrode-derived EASI electrocardiogram (ECG) with the conventional Mason-Likar ECG in 200 consecutive patients with chest pain transported to 3 hospitals by 2 different emergency medical services. No significant differences were observed between the 2 systems for the detection of relevant electrocardiographic abnormalities. A questionnaire administered to participating emergency medical personnel revealed a high degree of acceptability of the EASI ECG, with some participants commenting that the sternal and mid-axillary locations of the EASI electrodes made them easier to apply, especially to women, than conventional precordial electrodes.

Aged↗
PubMed2005

Pilot study of rapid infusion of 2 L of 4 degrees C normal saline for induction of mild hypothermia in hospitalized, comatose survivors of out-of-hospital cardiac arrest.

BACKGROUND: Recent clinical studies have demonstrated that mild hypothermia (32 degrees C to 34 degrees C) induced by surface cooling improves neurological outcome after resuscitation from out-of-hospital cardiac arrest. Results from animal models suggest that the effectiveness of mild hypothermia could be improved if initiated as soon as possible after return of spontaneous circulation. Infusion of cold, intravenous fluid has been proposed as a safe, effective, and inexpensive technique to induce mild hypothermia after cardiac arrest. METHODS AND RESULTS: In 17 hospitalized survivors of out-of-hospital cardiac arrest, we determined the effect on temperature and hemodynamics of infusing 2 L of 4 degrees C cold, normal saline during 20 to 30 minutes into a peripheral vein with a high-pressure bag. Data on vital signs, electrolytes, arterial blood gases, and coagulation were collected before and after fluid infusion. Cardiac function was assessed by transthoracic echocardiography before fluid administration and 1 hour after infusion. Passive (fans, leaving patient uncovered) or active (cooling blankets, neuromuscular blockade) cooling measures were used to maintain mild hypothermia for 24 hours. Infusion of 2 L of 4 degrees C cold, normal saline resulted in a mean temperature drop of 1.4 degrees C 30 minutes after the initiation of infusion. Rapid infusion of fluid was not associated with clinically important changes in vital signs, electrolytes, arterial blood gases, or coagulation parameters. The initial mean ejection fraction was 34%, and fluid infusion did not affect ejection fraction or increase central venous pressure, pulmonary pressures, or left atrial filling pressures as assessed by echocardiography. Passive measures were ineffective in maintaining hypothermia compared with active measures. CONCLUSIONS: Infusion of 2 L of 4 degrees C cold, normal saline is safe and effective in rapidly lowering body temperature in survivors of out-of-hospital cardiac arrest.

Adult↗