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Poor communication within healthcare teams occurs commonly, contributing to inefficiency, medical errors, conflict, and other adverse outcomes. Interprofessional bedside rounds (IBR) are a promising model that brings two or more health professions together with patients and families as part of a consistent, team-based routine to share information and collaboratively arrive at a daily plan of care. The purpose of this systematic scoping review was to investigate the breadth and quality of IBR literature to identify and describe gaps and opportunities for future research. We followed an adapted Arksey and O'Malley Framework and PRISMA scoping review guidelines. PubMed, CINAHL, PsycINFO, and Embase were systematically searched for key IBR words and concepts through June 2020. Seventy-nine articles met inclusion criteria and underwent data abstraction. Study quality was assessed using the Mixed Methods Assessment Tool. Publications in this field have increased since 2014, and the majority of studies reported positive impacts of IBR implementation across an array of team, patient, and care quality/delivery outcomes. Despite the preponderance of positive findings, great heterogeneity, and a reliance on quantitative non-randomized study designs remain in the extant research. A growing number of interventions to improve safety, quality, and care experiences in hospital settings focus on redesigning daily inpatient rounds. Limited information on IBR characteristics and implementation strategies coupled with widespread variation in terminology, study quality, and design create challenges in assessing the effectiveness of models of rounds and optimal implementation strategies. This scoping review highlights the need for additional studies of rounding models, implementation strategies, and outcomes that facilitate comparative research.

Objective To determine the efficacy of a program to limit the use of the intravenous (IV) push route for opioids on the experience of pain by inpatients and on associated safety events. Design Retrospective cohort study. Setting Two inpatient general medicine floor units at an urban tertiary care academic medical center. Subjects 4,752 inpatient opioid recipients. Methods Patients in one unit were exposed to a multidisciplinary intervention to limit the prescription of opioids via the IV push route, with the other unit used as a control unit. The primary study outcome was the mean numeric pain score per patient during the hospital stay. Secondary measures included the hospital length of stay and postdischarge patient satisfaction. Fidelity measures included the percentage of the patient population exposed to each opioid administration route and the amount of opioid administered per route. Safety measures included patient disposition, transfer to intensive care, and incidence of naloxone administration. Results The intervention was successful in decreasing both the percentage of patients exposed to IV push opioids and the amount of opioid administered via the IV push route, but no associated changes in other study outcomes were identified. Conclusions For the treatment of acute pain in medical inpatients, no evidence of benefit or harm was identified in relation to an increase or decrease in the use of the IV push opioid route.

Background Teamwork and collaboration are essential to providing high-quality care. Prior research has found discrepancies between nurses’ and physicians’ perceptions in operating rooms, ICUs, and labor and delivery units. Less is known about health care professionals’ perceptions of teamwork and collaboration on general medical services. Methods This cross-sectional study included nurses, nurse assistants, and physicians working on general medical services in four mid-sized hospitals. Researchers assessed teamwork climate using the Safety Attitudes Questionnaire and asked respondents to rate the quality of collaboration experienced with their own and other professional categories. Results Data for 380 participants (80 hospitalists, 13 resident physicians, 193 nurses, and 94 nurse assistants) were analyzed. Hospitalists had the highest median teamwork climate score (83.3, interquartile range [IQR] = 72.3–91.1), and nurses had the lowest (78.6, IQR = 69.6–87.5), but the difference was not statistically significant (p = 0.42). Median teamwork climate scores were significantly different across the four sites (highest = 83.3, IQR = 75.0–91.1; lowest = 76.8, IQR = 66.7–88.4; p = 0.003). Ratings of the quality of collaboration differed significantly based on professional category. Specifically, 63.3% (50/79) of hospitalists rated the quality of collaboration with nurses as high or very high, while 48.7% (94/193) of nurses rated the quality of collaboration with hospitalists as high or very high. Conclusion This study found significant differences in perceptions of teamwork climate across sites and in collaboration across professional categories on general medical services. Given the importance in providing high-quality care, leaders should consider conducting similar assessments to characterize teamwork and collaboration on general medical services within their own hospitals.

Background Hospital-based studies have reported variable associations between outcome after spontaneous intracerebral hemorrhage and peri-hematomal edema volume. Aims In a community-based study, we aimed to investigate the existence, strength, direction, and independence of associations between intracerebral hemorrhage and peri-hematomal edema volumes on diagnostic brain CT and one-year functional outcome and long-term survival. Methods We identified all adults, resident in Lothian, diagnosed with first-ever, symptomatic spontaneous intracerebral hemorrhage between June 2010 and May 2013 in a community-based, prospective inception cohort study. We defined regions of interest manually and used a semi-automated approach to measure intracerebral hemorrhage volume, peri-hematomal edema volume, and the sum of these measurements (total lesion volume) on first diagnostic brain CT performed at ≤3 days after symptom onset. The primary outcome was death or dependence (scores 3–6 on the modified Rankin Scale) at one-year after intracerebral hemorrhage. Results Two hundred ninety-two (85%) of 342 patients (median age 77.5 y, IQR 68–83, 186 (54%) female, median time from onset to CT 6.5 h (IQR 2.9–21.7)) were dead or dependent one year after intracerebral hemorrhage. Peri-hematomal edema and intracerebral hemorrhage volumes were colinear ( R2 = 0.77). In models using both intracerebral hemorrhage and peri-hematomal edema, 10 mL increments in intracerebral hemorrhage (adjusted odds ratio (aOR) 1.72 (95% CI 1.08–2.87); p = 0.029) but not peri-hematomal edema volume (aOR 0.92 (0.63–1.45); p = 0.69) were independently associated with one-year death or dependence. 10 mL increments in total lesion volume were independently associated with one-year death or dependence (aOR 1.24 (1.11–1.42); p = 0.0004). Conclusion Total volume of intracerebral hemorrhage and peri-hematomal edema, and intracerebral hemorrhage volume alone on diagnostic brain CT, undertaken at three days or sooner, are independently associated with death or dependence one-year after intracerebral hemorrhage, but peri-hematomal edema volume is not. Data access statement Anonymized summary data may be requested from the corresponding author.

BackgroundThe first Multi-center Medication Reconciliation Quality Improvement Study (MARQUIS1) demonstrated that implementation of a medication reconciliation best practices toolkit decreased total unintentional medication discrepancies in five hospitals. We sought to implement the MARQUIS toolkit in more diverse hospitals, incorporating lessons learned from MARQUIS1.MethodsMARQUIS2 is a pragmatic, mentored implementation QI study which collected clinical and implementation outcomes. Sites implemented a revised toolkit, which included interventions from these domains: 1) best possible medication history (BPMH)-taking; 2) discharge medication reconciliation and patient/caregiver counseling; 3) identifying and defining clinician roles and responsibilities; 4) risk stratification; 5) health information technology improvements; 6) improved access to medication sources; 7) identification and correction of real-time discrepancies; and, 8) stakeholder engagement. Eight hospitalists mentored the sites via one site visit and monthly phone calls over the 18-month intervention period. Each site’s local QI team assessed opportunities to improve, implemented at least one of the 17 toolkit components, and accessed a variety of resources (e.g. implementation manual, webinars, and workshops). Outcomes to be assessed will include unintentional medication discrepancies per patient.DiscussionA mentored multi-center medication reconciliation QI initiative using a best practices toolkit was successfully implemented across 18 medical centers. The 18 participating sites varied in size, teaching status, location, and electronic health record (EHR) platform.We introduce barriers to implementation and lessons learned from MARQUIS1, such as the importance of utilizing dedicated, trained medication history takers, simple EHR solutions, clarifying roles and responsibilities, and the input of patients and families when improving medication reconciliation.

BACKGROUND Hospital medical groups use various staffing models that may systematically affect care continuity during the admission process. OBJECTIVE To compare the effect of 2 hospitalist admission service models (“general” and “admitter-rounder”) on patient disposition and length of stay. DESIGN Retrospective observational cohort study with difference-in-difference analysis. SETTING Large tertiary academic medical center in the United States. PARTICIPANTS Patients (n = 19,270) admitted from the emergency department to hospital medicine and medicine teaching services from July 2010 to June 2013. INTERVENTIONS Admissions to hospital medicine staffed by 2 different service models, compared to teaching service admissions. MEASUREMENTS Incidence of transfer to critical care within the first 24 hours of hospitalization, hospital and emergency department length of stay, and hospital readmission rates ≤30 days postdischarge. RESULTS The change of hospitalist services to an admitter-rounder model was associated with no significant change in transfer to critical care or hospital length of stay compared to the teaching service (difference-in-difference P = 0.32 and P = 0.87, respectively). The admitter-rounder model was associated with decreased readmissions compared to the teaching service on difference-in-difference analysis (odds ratio difference: −0.21, P = 0.01). Adoption of the hospitalist admitter-rounder model was associated with an increased emergency department length of stay compared to the teaching service (difference of +0.49 hours, P < 0.001). CONCLUSIONS Rates of transfer to intensive care and overall hospital length of stay between the hospitalist admission models did not differ significantly. The hospitalist admitter-rounder admission service structure was associated with extended emergency department length of stay and a decrease in readmissions. Journal of Hospital Medicine 2016. © 2016 Society of Hospital Medicine

Background and Purpose— The characteristics of intracerebral hemorrhage (ICH) may vary by ICH location because of differences in the distribution of underlying cerebral small vessel diseases. Therefore, we investigated the incidence, characteristics, and outcome of lobar and nonlobar ICH. Methods— In a population-based, prospective inception cohort study of ICH, we used multiple overlapping sources of case ascertainment and follow-up to identify and validate ICH diagnoses in 2010 to 2011 in an adult population of 695 335. Results— There were 128 participants with first-ever primary ICH. The overall incidence of lobar ICH was similar to nonlobar ICH (9.8 [95% confidence interval, 7.7–12.4] versus 8.6 [95% confidence interval, 6.7–11.1] per 100 000 adults/y). At baseline, adults with lobar ICH were more likely to have preceding dementia (21% versus 5%; P =0.01), lower Glasgow Coma Scale scores (median, 13 versus 14; P =0.03), larger ICHs (median, 38 versus 11 mL; P P P =0.02) than those with nonlobar ICH. One-year case fatality was lower after lobar ICH than after nonlobar ICH (adjusted odds ratio for death at 1 year: lobar versus nonlobar ICH 0.21; 95% confidence interval, 0.07–0.63; P =0.006, after adjustment for known predictors of outcome). There were 4 recurrent ICHs, which occurred exclusively in survivors of lobar ICH (annual risk of recurrent ICH after lobar ICH, 11.8%; 95% confidence interval, 4.6%–28.5% versus 0% after nonlobar ICH; log-rank P =0.04). Conclusions— The baseline characteristics and outcome of lobar ICH differ from other locations.

Intrusion prevention systems (IPSs) determine whether incoming traffic matches a database of signatures, where each signature is a regular expression and represents an attack or a vulnerability. IPSs need to keep up with ever-increasing line speeds, which has lead to the use of custom hardware. A major bottleneck that IPSs face is that they scan incoming packets one byte at a time, which limits their throughput and latency. In this paper, we present a method to search for arbitrary regular expressions by scanning multiple bytes in parallel using speculation. We break the packet in several chunks, opportunistically scan them in parallel, and if the speculation is wrong, correct it later. We present algorithms that apply speculation in single-threaded software running on commodity processors as well as algorithms for parallel hardware. Experimental results show that speculation leads to improvements in latency and throughput in both cases.

Objective To assess the effect of tablet computers with a mobile patient portal application on hospitalized patients’ knowledge and activation. Methods We developed a mobile patient portal application including pictures, names, and role descriptions of team members, scheduled tests and procedures, and a list of active medications. We evaluated the effect of the application using a controlled trial involving 2 similar units in a large teaching hospital. Patients on the intervention unit were offered use of tablet computers with the portal application during their hospitalization. We assessed patients’ ability to correctly name their nurse, primary service physicians, physician roles, planned tests and procedures, medications started, and medications stopped since admission. We also administered the Short Form of the Patient Activation Measure. Results Overall, 100 intervention- and 102 control-unit patients participated. A higher percentage of intervention-unit patients correctly named ≥1 physician (56% vs 29.4%; P < .001) and ≥1 physician role (47% vs 15.7%; P < .001). Knowledge of nurses’ names, planned tests, planned procedures, and medication changes was generally low and not significantly different between the study units. The Short Form of the Patient Activation Measure mean (SD) score was also not significantly different at 64.1 (13.4) vs 62.7 (12.8); P = .46. Conclusions Additional research is needed to identify optimal methods to engage and inform patients during their hospitalization, which will improve preparation for self- management after discharge.

Public Service Company of Colorado (PSCo), in cooperation with the US Department of Energy (DOE) and the Electric Power Research Institute (EPRI), is testing the Integrated Dry NO{sub x}/SO{sub 2} Emissions Control system. This system combines low-NO{sub x} burners, overfire air, selective non-catalytic reduction (SNCR), and dry sorbent injection with humidification to reduce by up to 70% both NO{sub x} and SO{sub 2} emissions from a 100 MW coal-fired utility boiler. The project is being conducted at PSCo`s Arapahoe Unit 4 located in Denver, Colorado as part of the DOE`s Clean Coal Technology Round 3 program. The urea-based SNCR system, supplied by Noell, Inc., was installed in late 1991 and was tested with the unmodified boiler in 1992. At full load, it reduced NO{sub x} emissions by about 35% with an associated ammonia slip limit of 10 ppm. Babcock & Wilcox XLS{reg_sign} burners and a dual-zone overfire air system were retrofit to the top-fired boiler in mid-1992 and demonstrated a NO{sub x} reduction of nearly 70% across the load range. Integrated testing of the combustion modifications and the SNCR system were conducted in 1993 and showed that the SNCR system could reduce NO{sub x} emissions by an additional 45% whilemore » maintaining 10 ppm of ammonia slip limit at full load. Lower than expect4ed flue-gas temperatures caused low-load operation to be less effective than at high loads. NO{sub x} reduction decreased to as low as 11% at 60 MWe at an ammonia slip limit of 10 ppm. An ammonia conversion system was installed to improve performance at low loads. Other improvements to increase NO{sub x} removal at low-loads are planned. The combined system of combustion modifications and SNCR reduced NO{sub x} emissions by over 80% from the original full-load baseline. 11 figs.« less

The concept of Free Space Optical (FSO) communications has been around since the late 1960's.This paper will describe some recent experimental results that demonstrate and validate hybrid FSO/RF communication links as viable components in a tactical high data rate network. In particular, we will describe air-mountain link closure up to ranges of 200 km under heavy atmospheric turbulence. These links were operated at low packet and bit error rates, with occasional link outages. Like the internet, we used retransmission to minimize the effect of these outages on link throughput. For example, when the FSO system is running, ORCA uses the RF system for retransmission to improve link efficiency. In addition, we will discuss potential losses created by the aircraft aero-optics effects. Finally, we will show comparison between model predictions and experimental data that suggest we can predict link performance if the atmospheric turbulence conditions are known.

Intrusion prevention systems determine whether incoming traffic matches a database of signatures, where each signature in the database represents an attack or a vulnerability. IPSs need to keep up with ever-increasing line speeds, which leads to the use of custom hardware. A major bottleneck that IPSs face is that they scan incoming packets one byte at a time, which limits their throughput and latency. In this paper, we present a method for scanning multiple bytes in parallel using speculation. We break the packet in several chunks, opportunistically scan them in parallel and if the speculation is wrong, correct it later. We present algorithms that apply speculation in single-threaded software running on commodity processors as well as algorithms for parallel hardware. Experimental results show that speculation leads to improvements in latency and throughput in both cases.

Network Intrusion Detection Systems (NIDS) have become crucial to securing modern networks. To be effective, a NIDS must be able to counter evasion attempts and operate at or near wire-speed. Failure to do so allows malicious packets to slip through a NIDS undetected. In this paper, we explore NIDS evasion through algorithmic complexity attacks. We present a highly effective attack against the Snort NIDS, and we provide a practical algorithmic solution that successfully thwarts the attack. This attack exploits the behavior of rule matching, yielding inspection times that are up to 1.5 million times slower than that of benign packets. Our analysis shows that this attack is applicable to many rules in Snort?s ruleset, rendering vulnerable the thousands of networks protected by it. Our countermeasure confines the inspection time to within one order of magnitude of benign packets. Experimental results using a live system show that an attacker needs only 4.0 kbps of bandwidth to perpetually disable an unmodified NIDS, whereas all intrusions are detected when our countermeasure is used.

This paper describes a method for automatically inspecting the top edge region of a wafer for defects and how this method was used to evaluate process improvements. The need for such an inspection was driven by a within wafer defect problem first seen on product. The root cause of the defect was found to be the redistribution of certain defect types from the wafer edge exclusion region into the product area. Process partition and manual inspection using a scanning electron microscope (SEM) revealed the mechanism to be the formation and rupture of blisters during part of the process sequence. These blisters were found to be as small as 2μm, and appeared along the top edge of wafers. During processing, a high percentage of these blisters would rupture and redeposit debris on the topside of the wafer resulting in nearly 100 percent kill rate. While the root cause was understood, the use of SEM inspection to quantifiably evaluate process improvements intended to reduce the edge defects was impractical. This was deemed impractical because of the large of the number of wafers required to generate meaningful statistics and the number of process options. Additionally, manual inspections used to count the number of defects were inconsistent as well as slow. An automated macro defect inspection system (August Technology AXi Series 930) was used in a novel way to enable fast, accurate, and repeatable defect counts from the wafer top edge to help determine the most appropriate process improvement.

Partial or total duplication of document content is common to large digital libraries. We present a copy detection system to automate the detection of application in digital documents. The system we present is sentence-based and makes three contributions: it proposes an intuitive definition of similarity between documents; it produces the distribution of overlap that exists between overlapping documents; it is resistant to inaccuracy due to large variations in document size. We report the results of several experiments that illustrate the behavior and functionality of the system.

BACKGROUND: Patients who are refractory to platelet transfusion as a result of HLA alloimmunization are generally given HLA-matched or crossmatched platelets. However, HLA-matched platelets that are matched at HLA-A and -B loci (A-matched) or those without any mismatched or cross-reactive antigens (BU-matched) are frequently unavailable. A disadvantage of crossmatching is that crossmatched platelets have a shelf life of only 5 days, so that crossmatch tests must be performed frequently for patients requiring long-term platelet transfusions. An alternative method is the selection of platelets according to the patient's HLA antibody specificity, called the antibody specificity prediction (ASP) method. STUDY DESIGN AND METHODS: An anti-human globulin-enhanced microlymphocytotoxicity test modified by a double addition of serum and a computer program were used to determine the specificity of patients' HLA antibodies. Platelet crossmatching was performed with a solid-phase adherence assay. The percentage of platelet recovery (PPR) was determined in 1621 platelet transfusions in an observational study in 114 patients, and the PPR of platelets selected by the ASP method was compared with the PPR of those that were HLA-matched, crossmatched, or randomly selected. The numbers of potential donors in files of HLA-typed donors as identified by HLA matching vs. the ASP method were determined. RESULTS: After adjustments for covariates, the mean ± SEM PPR was similar for HLA-matched (21 ± 4%), cross-matched (23 ± 4%), and ASP-selected (24 ± 3%) platelets and was significantly lower for randomly selected (15 ± 1.4%) platelets. For 29 alloimmunized HLA-typed patients, the mean number of potential donors found in a file of 7247 HLA-typed donors was 6 who were an HLA-A match (median = 1), 33 who were an HLA-BU match (median = 20), and 1426 who were identified by the ASP method (median = 1365). CONCLUSION: The ASP method of donor selection for refractory alloimmunized patients appears as effective as HLA matching or crossmatching. Far more donors are identified in a file of HLA-typed donors by the ASP method than by HLA matching, and this indicates that the ASP method provides important advantages regarding the availability of compatible platelet components.

Objective. —Transesophageal echocardiography (TEE) and 12-lead electrocardiography (ECG) are sophisticated techniques that are increasingly being used to monitor for myocardial ischemia during noncardiac surgery. We examined whether the routine use of these techniques has incremental clinical value in identifying patients at high risk for perioperative ischemic outcomes when compared with preoperative clinical data and intraoperative monitoring using continuous two-lead bipolar ECG. Design. —Cohort study. Setting. —Veterans Affairs medical center. Patients. —A total of 332 men undergoing noncardiac surgery who had or were at high risk for coronary artery disease. Interventions. —TEE, 12-lead ECG, and two-lead ECG were performed continuously during noncardiac surgery (47% vascular, 53% nonvascular). Monitoring results were not available to anesthesiologists or surgeons, and data were blindly analyzed after surgery. Main Outcome Measure. —Perioperative ischemic outcomes (cardiac death, nonfatal myocardial infarction, unstable angina). Results. —In a subset of 285 patients who were adequately studied by all three techniques, 111 patients (39%) were identified as having intraoperative myocardial ischemia (by one or more monitoring techniques). By univariate analysis, intraoperative ischemia was associated with all perioperative cardiac outcomes, including ischemic outcomes, congestive heart failure, and ventricular tachycardia ( P ≤.02 for each of the three monitoring techniques). However, when monitoring results for TEE and 12-lead ECG were added to a multivariate model that included preoperative clinical data and continuous two-lead ECG results, the incremental value of TEE was small (odds ratio, 2.6; 95% confidence interval [Cl], 1.2 to 5.7; P =.02) and that of 12-lead ECG was not significant (odds ratio, 1.5; 95% Cl, 0.6 to 3.8). Furthermore, when the multivariate analysis was repeated with only ischemic outcomes, neither TEE nor 12-lead ECG retained significant associations (odds ratio, 2.2; 95% Cl, 0.5 to 9.4, and odds ratio, 1.1; 95% Cl, 0.2 to 6.1, respectively). Conclusion. —When compared with preoperative clinical data and intraoperative monitoring using two-lead ECG, routine monitoring for myocardial ischemia with TEE or 12-lead ECG during noncardiac surgery has little incremental clinical value in identifying patients at high risk for perioperative ischemic outcomes. ( JAMA . 1992;268:210-216)

Objective. —To identify predictors of postoperative myocardial ischemia in patients scheduled to undergo major noncardiac surgery. Design. —Historical, clinical, laboratory, and physiological data were obtained prospectively before and during surgery to identify potential univariate predictors of postoperative myocardial ischemia, which then were entered into multivariate logistic models. Continuous two-lead electrocardiograms before, during, and after surgery were used to identify episodes of myocardial ischemia. Setting. —Department of Veterans Affairs tertiary care hospital. Patients. —A consecutive sample of 474 men at high risk for or with coronary artery disease who were scheduled to undergo major noncardiac surgery (95% compliance rate). Main Outcome Measure. —Significant variables identified by multivariate logistic models that are associated with postoperative myocardial ischemia. Results. —Five major preoperative predictors of postoperative myocardial ischemia were identified: (1) left ventricular hypertrophy by electrocardiogram; (2) history of hypertension; (3) diabetes mellitus; (4) definite coronary artery disease; and (5) use of digoxin. The risk of postoperative myocardial ischemia increased progressively with the number of predictors present: in 22% of patients with no predictors, in 31% with one predictor, in 46% with two predictors, in 70% with three predictors, and in 77% with four predictors. Conclusion. —Patient subgroups who are at high risk for developing postoperative myocardial ischemia and who might benefit the most from intensive Holter monitoring in the postoperative period now can be identified preoperatively. ( JAMA . 1992;268:205-209)

Objective. —To determine the long-term (2-year) cardiac prognosis of high-risk patients undergoing noncardiac surgery and to determine the predictors of long-term adverse cardiac outcome. Design. —Prospective cohort study. Historical, clinical, and laboratory data were collected during the in-hospital period, and at 6 months, 1 year, and 2 years following surgery. Data were analyzed using proportional hazards models. Setting. —University-affiliated Veterans Affairs medical center. Population. —A consecutive sample of 444 patients with or at high risk for coronary artery disease who had undergone elective noncardiac surgery and were discharged from the hospital in stable condition. Main Outcome Measures. —Cardiac death, myocardial infarction, unstable angina, progressive angina requiring coronary artery bypass graft surgery or coronary angioplasty, and new unstable angina requiring hospitalization. Results. —Forty-seven patients (11%) had major cardiovascular complications during a 728-day (median) follow-up period: 24 had cardiac death; 11, nonfatal myocardial infarction; six, progressive angina requiring coronary artery bypass graft surgery or coronary angioplasty; and six, new unstable angina requiring hospitalization. Thirty percent of outcomes occurred within 6 months of surgery and 64% within 1 year. Five independent predictors of long-term outcome were identified. Three predictors reflected the preexisting chronic disease state: (1) the presence of known vascular disease (hazard ratio, 6.1; 95% confidence interval [Cl], 2.5 to 15.0; P P P P P P Conclusions. —The incidence of long-term adverse cardiac outcomes following noncardiac surgery is substantial. At increased risk are patients with chronic cardiovascular disease; at highest risk are patients with acute perioperative ischemic events. We conclude that survivors of in-hospital perioperative ischemic events, specifically myocardial infarction, unstable angina, and postoperative ischemia, warrant more aggressive long-term follow-up and treatment than is currently practiced. ( JAMA . 1992;268:233-239)

Objective. —To determine the incidence, clinical predictors and prognostic importance of perioperative ventricular arrhythmias. Design. —Prospective cohort study (Study of Perioperative Ischemia). Setting. —University-affiliated Department of Veterans Affairs Medical Center, San Francisco, Calif. Subjects. —A consecutive sample of 230 male patients, with known coronary artery disease (46%) or at high risk of coronary artery disease (54%), undergoing major noncardiac surgical procedures. Measurements. —We recorded cardiac rhythm throughout the preoperative (mean=21 hours), intraoperative (mean=6 hours), and postoperative (mean=38 hours) periods using continuous ambulatory electrocardiographic monitoring. Adverse cardiac outcomes were noted by physicians blinded to information about arrhythmias. Main Results. —Frequent or major ventricular arrhythmias (>30 ventricular ectopic beats per hour, ventricular tachycardia) occurred in 44% of our patients: 21% preoperatively, 16% intraoperatively, and 36% postoperatively. Compared with the preoperative baseline, the severity of arrhythmia increased in only 2% of patients intraoperatively but in 10% postoperatively. Preoperative ventricular arrhythmias were more common in smokers (odds ratio [OR], 4.1; 95% confidence interval [Cl], 1.2 to 15.0), those with a history of congestive heart failure (OR, 4.1; 95% Cl, 1.9 to 9.0), and those with electrocardiographic evidence of myocardial ischemia (OR, 2.2; 95% Cl, 1.1 to 4.7). Preoperative arrhythmias were associated with the occurrence of intraoperative and postoperative arrhythmias (OR, 7.3; 95% CI, 3.3 to 16.0, and OR, 6.4; 95% Cl, 2.7 to 15.0, respectively). Nonfatal myocardial infarction or cardiac death occurred in nine men; these outcomes were not significantly more frequent in those with prior perioperative arrhythmias, albeit with wide Cls (OR, 1.6; 95% CI, 0.4 to 6.2). Conclusion. —Almost half of all high-risk patients undergoing noncardiac surgery have frequent ventricular ectopic beats or nonsustained ventricular tachycardia. Our results suggest that these arrhythmias, when they occur without other signs or symptoms of myocardial infarction, may not require aggressive monitoring or treatment during the perioperative period. (JAMA. 1992;268:217-221)

This study focuses on growth and change in the urban system of the Republic of Korea over the past three decades. In an analysis of system-wide and subregional growth trends with particular emphasis given to the Gini coefficient of population concentration two stages of development are identified. During the 1950s and early 1960s the system experienced numerical and spatial expansion along with growing concentration in the largest centers. Since the late 1960s the main process has been concentrated in Seoul and in the places immediately below it in the city-size distribution. Spatially this concentration has taken the form of a core-corridor from Seoul to Busan. It is shown that "in large part these changes reflect the transformation to an urban-industrial economy but they also reflect government policies which have focused heavily on Seoul but perhaps not heavily enough on the spatial distribution of other large centers in the urban system." (EXCERPT)