Socio-ecological correlates of neophobia in corvids.

Behavioral responses to novelty, including fear and subsequent avoidance of novel stimuli, i.e., neophobia, determine how animals interact with their environment. Neophobia aids in navigating risk and impacts on adaptability and survival. There is variation within and between individuals and species; however, lack of large-scale, comparative studies critically limits investigation of the socio-ecological drivers of neophobia. In this study, we tested responses to novel objects and food (alongside familiar food) versus a baseline (familiar food alone) in 10 corvid species (241 subjects) across 10 labs worldwide. There were species differences in the latency to touch familiar food in the novel object and novel food conditions relative to the baseline. Four of seven socio-ecological factors influenced object neophobia: (1) use of urban habitat (versus not), (2) territorial pair versus family group sociality, (3) large versus small maximum flock size, and (4) moderate versus specialized caching (whereas range, hunting live animals, and genus did not), while only maximum flock size influenced food neophobia. We found that, overall, individuals were temporally and contextually repeatable (i.e., consistent) in their novelty responses in all conditions, indicating neophobia is a stable behavioral trait. With this study, we have established a network of corvid researchers, demonstrating potential for further collaboration to explore the evolution of cognition in corvids and other bird species. These novel findings enable us, for the first time in corvids, to identify the socio-ecological correlates of neophobia and grant insight into specific elements that drive higher neophobic responses in this avian family group. VIDEO ABSTRACT.

Dog and owner characteristics predict training success.

Teaching owners how to train their dogs is an important part of maintaining the health and safety of dogs and people. Yet we do not know what behavioral characteristics of dogs and their owners are relevant to dog training or if owner cognitive abilities play a role in training success. The aim of this study is to determine which characteristics of both dogs and owners predict success in completing the American Kennel Club Canine Good Citizen training program. Before the first session of a dog training course, owners completed surveys evaluating the behavior and cognition of their dog and themselves. Additionally, we collected the dogs' initial training levels via behavioral tasks. We then examined what factors predicted whether the dogs passed the Canine Good Citizen test after the class ended. In terms of dog characteristics, we found that, while dog age, sex and neuter status did not predict success, owner-rated levels of disobedience did predict completion of the program. In terms of owner characteristics, owners who scored higher on cognitive measures were more likely to have their dogs complete the program. Finally, dog-owner characteristics such as the time spent training predicted success. Thus, characteristics of the dogs, owners, and how they interact seem to predict training success. These findings suggest that there are some owner, dog, and dog-owner characteristics that can facilitate or hinder dog training.

Safety climate and workplace violence prevention in state-run residential addiction treatment centers.

OBJECTIVE: To examine the association between violence prevention safety climate measures and self reported violence toward staff in state-run residential addiction treatment centers. METHODS: In mid-2006, 409 staff from an Eastern United States state agency that oversees a system of thirteen residential addiction treatment centers (ATCs) completed a self-administered survey as part of a comprehensive risk assessment. The survey was undertaken to identify and measure facility-level risk factors for violence, including staff perceptions of the quality of existing US Occupational Safety and Health Administration (OSHA) program elements, and ultimately to guide violence prevention programming. Key informant interviews and staff focus groups provided researchers with qualitative data with which to understand safety climate and violence prevention efforts within these work settings. RESULTS: The frequency with which staff reported experiencing violent behavior ranged from 37% for "clients raised their voices in a threatening way to you" to 1% for "clients pushed, hit, kicked, or struck you". Findings from the staff survey included the following significant predictors of violence: "client actively resisting program" (OR=2.34, 95% CI=1.35, 4.05), "working with clients for whom the history of violence is unknown" (OR=1.91, 95% CI=1.18, 3.09) and "management commitment to violence prevention" reported as "never/hardly ever" and "seldom or sometimes" (OR=4.30 and OR=2.31 respectively), while controlling for other covariates. CONCLUSIONS: We utilized a combination of qualitative and quantitative research methods to begin to describe the risk and potential for violence prevention in this setting. The prevalence of staff physical violence within the agency's treatment facilities was lower than would be predicted. Possible explanations include the voluntary nature of treatment programs; strong policies and consequences for resident behavior and ongoing quality improvement efforts. Quantitative data identified low management commitment to violence prevention as a significant predictor of staff reported violence.

The relationship between weight, age, and average daily gain to show performance of Georgia 4-H and Future Farmers of America (FFA) commercial dairy heifers.

Three studies were conducted to determine the relationship between dairy heifer growth and placing in the show ring. In the first study, 1,744 commercial dairy heifers (all breeds and crossbred animals) were evaluated to determine effects of growth on placing within Georgia Commercial Dairy Heifer Shows from 2007 to 2010. Birth weights were determined using breed birth weight averages, with crossbreeds being the average of 2 parent breeds. Average daily gains (ADG) were calculated and heifers were given rankings based on placing in show and for age and weight. Data was analyzed using the Spearman correlation calculations in the SAS software (SAS Institute Inc., Cary, NC). Age and ADG were inversely correlated (r=-0.89). Mean ADG for all heifers was determined to be 0.65 kg, below National Research Council recommendations of 0.7 to 0.8 kg. No strong relationship (r=-0.07) was observed between ADG and placing. Heavier heifers within a class showed a small positive relationship (r=0.10) with placing. For study 2, 238 heifers shown at the 2010 Georgia Junior National Livestock Show (Perry, GA) were measured and evaluated for ADG, placing, body weight, age, withers height, hip height, hip width, and jaw width. Height at withers had a moderate relationship (r=0.42) with placing, followed by hip height (r=0.32). A positive relationship (r=0.65) was observed between withers height and hip height. The correlation between weight and placing was determined (r=0.11). Age and ADG had a strong inverse relationship (r=-0.87). Study 3 evaluated 1,489 Holstein heifers shown from 2007 to 2010. Data was analyzed using the Penn State Growth Monitor Spreadsheet Curves. In total, 63.75% did not meet Penn State recommendations for body weight gain. Performance and physical features associated with age indicates that commercial dairy heifers are underfed. The effects of heat stress and high feed costs also play a role. This has economic implications because these animals will likely require more time before they enter the milk herd. The Commercial Dairy Heifer Program is vital for youth development in Georgia. However, those involved need to be encouraged to improve nutritional management practices.

Characterizing spatio-temporal patterns for disease discrimination in cardiac echo videos.

Disease-specific understanding of echocardiographic sequences requires accurate characterization of spatio-temporal motion patterns. In this paper we present a method of automatic extraction and matching of spatio-temporal patterns from cardiac echo videos. Specifically, we extract cardiac regions (chambers and walls) using a variation of multiscale normalized cuts that combines motion estimates from deformable models with image intensity. We then derive spatio-temporal trajectories of region measurements such as wall motion, volume and thickness. The region trajectories are then matched to infer the similarities in disease labels of patients. Validation results on patient data sets collected from many hospitals are presented.

Aprotinin and perioperative complications in cardiac surgery.

AIM: Recently, the clinical significance of aprotinin-induced renal dysfunction and other end-organ complications in patients undergoing cardiac surgery has engendered substantial controversy. Therefore, we assessed the effect of aprotinin on end-organ complications in patients undergoing cardiac surgery. METHODS: Data of 674 patients (mean age 65.4 +/- 11.0 years, 457 males) undergoing cardiac surgery between January 1 and December 31, 2005 at Semmelweis University were used for the analyses. Preoperative, intraoperative and postoperative clinical and surgical variables were recorded. Patients administered aprotinin received the drug either as a low-dose regimen, a loading dose of 1 million kallikrein-inhibitor units (KIU), 1 million KIU in pump, and 1 million KIU post pump (or continuous infusion of 0.25 million KIU per hour); or a high-dose regimen, a loading dose of 2 million KIU, 2 million KIU in pump, and 2 million KIU post pump (or continuous infusion of 0.5 million KIU per hour). The outcomes were renal complications defined as a 25% reduction in postoperative calculated creatinine clearance compared to the preoperative baseline or renal failure requiring dialysis; and the composite of renal, cardiovascular and cerebrovascular complications and all-cause mortality. RESULTS: Patients underwent coronary artery bypass surgery (63%), valvular (27%) or a combination (5%) and surgery on the ascending aorta (5%). There were 550 patients (81.6%) who received aprotinin treatment. In multivariate regression analyses when the relation between high or low dose aprotinin compared to no aprotinin was evaluated, the likelihood of renal complications [high dose: odds ratio (OR)=1.4, 95% confidence interval (CI), 0.6-3.0, P=0.4; low dose: OR=1.2, 95%CI, 0.7-2.3, p=0.5], and the composite outcome variable (high dose: OR=1.6, 95%CI, 0.8-3.4, P=0.2; low dose: OR=1.3, 95%CI, 0.7-2.3, P=0.4) were not significantly increased. CONCLUSION: Our analysis suggests that aprotinin use in either a high or low dose regimen was not associated with an increase in adverse end-organ complications.

Abnormal frontal activations related to decision-making in current and former amphetamine and opiate dependent individuals.

RATIONALE: There is converging evidence for impairments in decision-making in chronic substance users. In the light of findings that substance abuse is associated with disruptions of the functioning of the striato-thalamo-orbitofrontal circuits, it has been suggested that decision-making impairments are linked to frontal lobe dysfunction. We sought to investigate this possibility using functional neuroimaging. METHODS: Decision-making was investigated using the Cambridge Risk Task during H2(15)O PET scans. A specific feature of the Risk Task is the decisional conflict between an unlikely high reward option and a likely low reward option. Four groups, each consisting of 15 participants, were compared: chronic amphetamine users, chronic opiate users, ex-drug users who had been long-term amphetamine/opiate users but are abstinent from all drugs of abuse for at least 1 year and healthy matched controls without a drug-taking history. RESULTS: During decision-making, control participants showed relatively greater activation in the right dorsolateral prefrontal cortex, whereas participants engaged in current or previous drug use showed relatively greater activation in the left orbitofrontal cortex. CONCLUSION: Our results indicate a disturbance in the mediation by the prefrontal cortex of a risky decision-making task associated with amphetamine and opiate abuse. Moreover, this disturbance was observed in a group of former drug users who had been abstinent for at least 1 year.

Negative-Pressure monitoring of tuberculosis isolation rooms within New York State hospitals.

A previously published study recommended the daily use of visible smoke to test for negative air pressure in isolation rooms occupied by potentially infectious tuberculosis cases. Continuous monitoring devices were found to have poor reliability. Findings from our survey of engineering controls in acute-care hospitals within New York State support this recommendation.

Myocardial ischemia. Monitoring to diagnose ischemia: how do I monitor therapy?

Diagnosis of myocardial ischemia requires integration of ECG, pulmonary artery pressures, and TEE data. ST depression of 1 mV or elevation of 2 mV remains the mainstay of diagnosis of ischemia. Increases of pulmonary artery pressures of 5 mm Hg are common but not reliably diagnostic of ischemia. Transesophageal echocardiography is the most sensitive monitor of ischemia, where the spectra of SWMA evolve. Diastolic dysfunction (elevations in LVEDP) is a more sensitive marker of ischemia, but requires measurement of several Doppler patterns. After diagnosis, treatment should include optimization of hemodynamics (beginning with beta-blockers and nitrates), anesthesia, and oxygen-carrying capacity (e.g., normothermia, oxygen saturation, hematocrit more than 28%).

Assessment of pain in cognitively impaired older adults: a comparison of pain assessment tools and their use by nonprofessional caregivers.

OBJECTIVES: To compare self-reporting of pain by cognitively impaired (CI) older adults living in the community with reports of their caregivers; to identify the factors associated with differences in agreement; and to identify those pain assessment tools that are most useful to nonprofessional caregivers. DESIGN: Prospective observational cohort of patients with dementia and their caregivers. SETTING: In-home assessments of community-dwelling CI older adults and family members, adult foster care providers, or aides in residential care facilities. All CI subjects were enrolled in a Program for All-inclusive Care of the Elderly program (ElderPlace) in Portland, Oregon. PARTICIPANTS: A total of 156 CI adults and their caregivers. METHODS: Standardized pain assessment instruments were administered to the CI subjects and their caregivers in the subject's home by trained research assistants between June and October 1998. CI subjects were assessed with the Nonverbal Visual Analog scale ("line"), the Faces Pain Scale ("faces"), and the Philadelphia Pain Intensity Scale (PIS). Research assistants observed pain behaviors in the CI subjects using the Hospice Approach Discomfort Scale. The CI subject's caregivers completed the "line," "faces," PIS, and Cornell Scale for Depression in Dementia. A baseline Mini-Mental State Exam, Functional Assessment Stage Test, and Geriatric Depression Scale were performed on all CI subjects by ElderPlace medical, nursing, or social work staff. RESULTS: The mean age of the CI subjects was 83, and 83% were women. The mean Mini-Mental State Exam score was 15.7. One-third of the CI subjects were unable to complete any of the three pain assessment tools. Of the 104 subjects completing at least one tool, 13 (12.5%) reported no pain and 91 (87.5%) reported some pain. Sixteen (10%) of the subjects were depressed as measured with the GDS or Cornell instrument. In 70 of the 104 subjects (67%) able to complete any tool, the caregiver and CI subject agreed as to the level of pain experienced by the CI subject. The number of tools completed by the CI subjects decreased with increased cognitive impairment. The Pain Intensity Scale was the tool most likely to be completed by both CI subjects and caregivers. The means of test scores were not significantly different for the paired groups of CI subject and caregiver, and the nonparametric correlation of each tool was significant: "faces" (Spearman's rho (p) = .417); "line" (p = .420); and PIS (p = .452). The Hospice Approach Discomfort Scale did not correlate well with other tools. The Pain Intensity Scale seems to be more useful than other pain assessment tools in assessing pain in cognitively impaired patients and can be used by nonprofessional caregivers in a community-based care setting.

Subthreshold voltage noise due to channel fluctuations in active neuronal membranes.

Voltage-gated ion channels in neuronal membranes fluctuate randomly between different conformational states due to thermal agitation. Fluctuations between conducting and nonconducting states give rise to noisy membrane currents and subthreshold voltage fluctuations and may contribute to variability in spike timing. Here we study subthreshold voltage fluctuations due to active voltage-gated Na+ and K+ channels as predicted by two commonly used kinetic schemes: the Mainen et al. (1995) (MJHS) kinetic scheme, which has been used to model dendritic channels in cortical neurons, and the classical Hodgkin-Huxley (1952) (HH) kinetic scheme for the squid giant axon. We compute the magnitudes, amplitude distributions, and power spectral densities of the voltage noise in isopotential membrane patches predicted by these kinetic schemes. For both schemes, noise magnitudes increase rapidly with depolarization from rest. Noise is larger for smaller patch areas but is smaller for increased model temperatures. We contrast the results from Monte Carlo simulations of the stochastic nonlinear kinetic schemes with analytical, closed-form expressions derived using passive and quasi-active linear approximations to the kinetic schemes. For all subthreshold voltage ranges, the quasi-active linearized approximation is accurate within 8% and may thus be used in large-scale simulations of realistic neuronal geometries.

Physician orders for life-sustaining treatment (POLST): outcomes in a PACE program. Program of All-Inclusive Care for the Elderly.

OBJECTIVES: To evaluate whether terminal care was consistent with Physician Orders for Life-Sustaining Treatment (POLST), a preprinted and signed doctor's order specifying treatment instructions in the event of serious illness for CPR, levels of medical intervention, antibiotics, IV fluids, and feeding tubes. DESIGN: Retrospective chart review. SETTING: ElderPlace, a Program of All-Inclusive Care for the Elderly (PACE) site in Portland, Oregon. PARTICIPANTS: All ElderPlace participants who died in 1997 were eligible (n = 58). Reasons for exclusion were no POLST (1), missing POLST (1), and insufficient documentation of care (2). MEASUREMENTS: POLST instructions for each participant and whether or not each of the treatments addressed by the POLST was administered in the final 2 weeks of life. RESULTS: The POLST specified "do not resuscitate" for 50 participants (93%); CPR use was consistent with these instructions for 49 participants (91%). "Comfort care" was the designated level of medical intervention in 13 cases, "limited interventions" in 18, "advanced interventions" in 18, and "full interventions" in 5. Interventions administered were at the level specified in 25 cases (46%); at a less invasive level in 18 (33%), and at a more invasive level in 11 (20%). Antibiotic administration was consistent with POLST instructions for 86% of 28 subjects who had infections in the last 2 weeks of life, and less invasive for 14%. Care matched POLST instructions in 84% of cases for IV fluids and 94% for feeding tubes. CONCLUSIONS: POLST completion in ElderPlace exceeds reported advance directive rates. Care matched POLST instructions for CPR, antibiotics, IV fluids, and feeding tubes more consistently than previously reported for advance directive instructions. Medical intervention level was consistent with POLST instructions for less than half the participants, however. We conclude that the POLST is effective for limiting the use of some life-sustaining interventions, but that the factors that lead physicians to deviate from patients' stated preferences merit further investigation.

Untangling dendrites with quantitative models.

Our understanding of the function of dendrites has been greatly enriched by an inspiring dialogue between theory and experiments. Rather than functionally ignoring dendrites, representing neurons as single summing points, we have realized that dendrites are electrically and chemically distributed nonlinear units and that this has important consequences for interpreting experimental data and for the role of neurons in information processing. Here, we examine the route to unraveling some of the enigmas of dendrites and highlight the main insights that have been gained. Future directions are discussed that will enable theory and models to keep shedding light on dendrites, where the most fundamental input-output adaptive processes take place.

Profiles of cognitive dysfunction in chronic amphetamine and heroin abusers.

Groups of subjects whose primary drug of abuse was amphetamine or heroin were compared, together with age- and IQ-matched control subjects. The study consisted of a neuropsychological test battery which included both conventional tests and also computerised tests of recognition memory, spatial working memory, planning, sequence generation, visual discrimination learning, and attentional set-shifting. Many of these tests have previously been shown to be sensitive to cortical damage (including selective lesions of the temporal or frontal lobes) and to cognitive deficits in dementia, basal ganglia disease, and neuropsychiatric disorder. Qualitative differences, as well as some commonalities, were found in the profile of cognitive impairment between the two groups. The chronic amphetamine abusers were significantly impaired in performance on the extra-dimensional shift task (a core component of the Wisconsin Card Sort Test) whereas in contrast, the heroin abusers were impaired in learning the normally easier intra-dimensional shift component. Both groups were impaired in some of tests of spatial working memory. However, the amphetamine group, unlike the heroin group, were not deficient in an index of strategic performance on this test. The heroin group failed to show significant improvement between two blocks of a sequence generation task after training and additionally exhibited more perseverative behavior on this task. The two groups were profoundly, but equivalently impaired on a test of pattern recognition memory sensitive to temporal lobe dysfunction. These results indicate that chronic drug use may lead to distinct patterns of cognitive impairment that may be associated with dysfunction of different components of cortico-striatal circuitry.

Group and case study of the dysexecutive syndrome in alcoholism without amnesia.

OBJECTIVES: To test the dysexecutive syndrome (DES) hypothesis of chronic alcoholism by the neuropsychological group and case study approaches. METHODS: A comprehensive neuropsychological assessment, including the "behavioural assessment of dysexecutive syndrome", a battery of tests recently designed to be "ecologically valid", was administered to 17 patients with chronic alcoholism without amnesia to examine executive functions, intelligence, and memory. In terms of each neuropsychological measure, reciprocal analyses of group means and individual case profiles were conducted: for the first contrasting the alcoholic patients with 17 age matched healthy subjects; and for the second making intersubject and intrasubject comparison of the patients, according to percentile basis impairment indices obtained from the control subjects. RESULTS: Despite relatively unimpaired memory and intelligence, the patients as a whole had the impairment of a wide range of executive domains, extending to "everyday" problem solving as well as more elementary aspects of executive functions, such as visuospatial performance, mental set shifting, and the inhibition of habitual behaviour. The profile analysis divided individual patients into four groups: the representative DES characterised by a clear dissociation between impaired executive functions and preserved intelligence and memory; the group of a modified dysexecutive pattern in which memory as well as executive functions were impaired with intelligence preserved; the group of general cognitive deterioration; and the group of unimpaired cognitive functioning. About two thirds of the patients were categorised into either the first or the second type of DES. CONCLUSION: DES characterised by the even more pronounced impairment of executive functions than of intelligence and memory afflicts a considerable proportion of patients with chronic alcoholism. Due to its subtlety, this would be potentially left out, unless appropriate behavioural measures were administered. This condition may prevent patients with alcoholism from achieving full recovery and benefiting from rehabilitation.

Identification of factors that disrupt negative air pressurization of respiratory isolation rooms.

OBJECTIVES: To investigate the airflow characteristics of respiratory isolation rooms (IRs) and to evaluate the use of visible smoke as a monitoring tool. METHODS: Industrial hygienists from the New York State Department of Health evaluated 140 designated IRs in 38 facilities within New York State during 1992 to 1998. The rooms were located in the following settings: hospitals (59%), correctional facilities (40%), and nursing homes (1%). Each room was tested with visible smoke for directional airflow into the patient room (ie, negative air pressure relative to adjacent areas). Information was obtained on each facility's policies and procedures for maintaining and monitoring the operation of the IRs. RESULTS: Inappropriate outward airflow was observed in 38% of the IRs tested. Multiple factors were associated with outward airflow direction, including ventilation systems not balanced (54% of failed rooms), shared anterooms (14%), turbulent airflow patterns (11%), and automated control system inaccuracies (10%). Of the 140 tested rooms, 38 (27%) had either electrical or mechanical devices to monitor air pressurization continuously. The direction of airflow at the door to 50% (19/38) of these rooms was the opposite of that indicated by the continuous monitors at the time of our evaluations. The inability of continuous monitors to indicate the direction of airflow was associated with instrument limitations (74%) and malfunction of the devices (26%). In one facility, daily smoke testing by infection control staff was responsible for identifying the malfunction of a state-of-the-art computerized ventilation monitoring and control system in a room housing a patient infectious with drug-resistant tuberculosis. CONCLUSION: A substantial percentage of IRs did not meet the negative air pressure criterion. These failures were associated with a variety of characteristics in the design and operation of the IRs. Our findings indicate that a balanced ventilation system does not guarantee inward airflow direction. Devices that continuously monitor and, in some cases, control the pressurization of IRs had poor reliability. This study demonstrates the utility of using visible smoke for testing directional airflow of IRs, whether or not continuous monitors are used. Institutional tuberculosis control pro grams should include provisions for appropriate monitoring and maintenance of IR systems on a frequent basis, including the use of visible smoke.

Association of fast-track cardiac management and low-dose to moderate-dose glucocorticoid administration with perioperative hyperglycemia.

OBJECTIVE: To delineate associations between preoperative risk factors and clinical processes of care and perioperative glucose tolerance in patients managed on a fast-track cardiac surgery clinical pathway with prebypass methylprednisolone administration. DESIGN: Retrospective sequential cohort study. SETTING: University-affiliated Department of Veterans Affairs medical center. PARTICIPANTS: Fast-track patients (n = 293; n = 72 low-dose methylprednisolone [100-125 mg]; n = 221 moderate-dose methylprednisolone [500 mg]) plus pre-fast-track patients (n = 258; no methylprednisolone) undergoing cardiac surgery with cardiopulmonary bypass. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Multivariate linear regression was used to model the association of 17 preoperative risk and intraoperative process-of-care variables with serum glucose concentration on arrival in the intensive care unit. Preoperative serum glucose concentrations were not significantly different among the pre-fast-track, fast-track with low-dose methylprednisolone, and fast-track with moderate-dose methylprednisolone cohorts (129 +/- 54, 137 +/- 55, 127 +/- 46 mg/dL [mean +/- SD]). Postoperative serum glucose concentrations were significantly different (171 +/- 58, 223 +/- 56, 250 +/- 75 mg/dL; p < 0.03, for all pairwise comparisons). Using backward elimination from the full 17-variable multivariate model (R-square = 0.63), 4 variables remained significant (all p < 0.0001; R-square = 0.60): (1) Preoperative diabetes status (adjusted mean post-operative glucose level, mg/dL; [95% confidence interval (CI)]): no treatment, 193 (188-199); oral agent, 276 (262-291); insulin requiring, 301 (283-320); (2) steroid group: pre-fast-track, 201 (195-209), fast-track with low-dose methylprednisolone, 271 (256-287); fast-track with moderate-dose methylprednisolone, 295 (284-306); (3) volume of glucose-containing cardioplegia (beta coefficient, 95% CI): 2.22% (1.37-3.10) increase per 100 mL; and (4) intraoperative epinephrine infusion: none, 231 (224-239); yes, 276 (264-288). No significant interactions were identified. No significant effect of opioid dose was observed. CONCLUSION: At this institution, implementation of the fast-track pathway was associated with a deterioration of glucose tolerance. Preoperative diabetes, pre-cardiopulmonary bypass administration of steroids, volume of glucose-containing cardioplegia solution administered, and use of epinephrine infusions were significantly associated multivariate factors.