Showing papers by "Deborah J. Cook published in 1998"

Incidence of and Risk Factors for Ventilator-Associated Pneumonia in Critically Ill Patients

Abstract: Background: Understanding the risk factors for ventilator-associated pneumonia can help to assess prognosis and devise and test preventive strategies Objective: To examine the baseline and time-de

Evaluation of a ventilation strategy to prevent barotrauma in patients at high risk for acute respiratory distress syndrome. Pressure- and Volume-Limited Ventilation Strategy Group.

Abstract: Background A strategy of mechanical ventilation that limits airway pressure and tidal volume while permitting hypercapnia has been recommended for patients with the acute respiratory distress syndrome. The goal is to reduce lung injury due to overdistention. However, the efficacy of this approach has not been established. Methods Within 24 hours of intubation, patients at high risk for the acute respiratory distress syndrome were randomly assigned to either pressure- and volume-limited ventilation (limited-ventilation group), with the peak inspiratory pressure maintained at 30 cm of water or less and the tidal volume at 8 ml per kilogram of body weight or less, or to conventional ventilation (control group), with the peak inspiratory pressure allowed to rise as high as 50 cm of water and the tidal volume at 10 to 15 ml per kilogram. All other ventilatory variables were similar in the two groups. Results A total of 120 patients with similar clinical features underwent randomization (60 in each group). The ...

A comparison of sucralfate and ranitidine for the prevention of upper gastrointestinal bleeding in patients requiring mechanical ventilation. Canadian Critical Care Trials Group.

Abstract: Background Critically ill patients who require mechanical ventilation are at increased risk for gastrointestinal bleeding from stress ulcers. There are conflicting data on the effect of histamine H2-receptor antagonists and the cytoprotective agent sucralfate on rates of gastrointestinal bleeding, ventilator-associated pneumonia, and mortality. Methods In a multicenter, randomized, blinded, placebo-controlled trial, we compared sucralfate with the H2-receptor antagonist ranitidine for the prevention of upper gastrointestinal bleeding in 1200 patients who required mechanical ventilation. Patients received either nasogastric sucralfate suspension (1 g every six hours) and an intravenous placebo or intravenous ranitidine (50 mg every eight hours) and a nasogastric placebo. Results The patients in the two groups had similar base-line characteristics. Clinically important gastrointestinal bleeding developed in 10 of 596 (1.7 percent) of the patients receiving ranitidine, as compared with 23 of 604 (3.8 percent...

Methodology and reports of systematic reviews and meta-analyses: a comparison of Cochrane reviews with articles published in paper-based journals.

Abstract: Context.—Review articles are important sources of information to help guide decisions by clinicians, patients, and other decision makers. Ideally, reviews should include strategies to minimize bias and to maximize precision and be reported so explicitly that any interested reader would be able to replicate them.Objective.—To compare the methodological and reporting aspects of systematic reviews and meta-analyses published by the Cochrane Collaboration with those published in paper-based journals indexed in MEDLINE.Data Sources.—The Cochrane Library, issue 2 of 1995, and a search of MEDLINE restricted to 1995.Study Selection.—All 36 completed reviews published in the Cochrane Database of Systematic Reviews and a randomly selected sample of 39 meta-analyses or systematic reviews published in journals indexed by MEDLINE in 1995.Data Extraction.—Number of authors, trials, and patients; trial sources; inclusion and exclusion criteria; language restrictions; primary outcome; trial quality assessment; heterogeneity testing; and effect estimates. Updating by 1997 was evaluated.Results.—Reviews found in MEDLINE included more authors (median, 3 vs 2; P<.001), more trials (median, 13.5 vs 5; P<.001), and more patients (median, 1280 vs 528; P <.001) than Cochrane reviews. More Cochrane reviews, however, included a description of the inclusion and exclusion criteria (35/36 vs 18/39; P<.001) and assessed trial quality (36/36 vs 12/39; P<.001). No Cochrane reviews had language restrictions (0/36 vs 7/39; P<.01). There were no differences in sources of trials, heterogeneity testing, or description of effect estimates. By June 1997, 18 of 36 Cochrane reviews had been updated vs 1 of 39 reviews listed in MEDLINE.Conclusions.—Cochrane reviews appear to have greater methodological rigor and are more frequently updated than systematic reviews or meta-analyses published in paper-based journals.

Does This Patient Have Deep Vein Thrombosis

Abstract: ContextOutpatients with suspected deep vein thrombosis (DVT) have nonspecific signs and symptoms. Missed DVT diagnosis may result in fatal pulmonary embolism. Since many patients may have DVT, a selective and efficient diagnostic process is needed.ObjectiveTo systematically review trials that determined the prevalence of DVT using clinical prediction rules either with or without D-dimer, for the diagnosis of DVT.Data SourcesEnglish- and French-language studies were identified from MEDLINE from 1990 to July 2004 and supplemented by a review of all relevant bibliographies.Study SelectionWe included studies that prospectively enrolled consecutive, unselected outpatients with suspected DVT and applied clinical prediction rules before D-dimer testing or diagnostic imaging. All studies included sufficient information to allow the calculation of the prevalence of DVT for at least 1 of the 3 clinical probability estimates (low, moderate, or high). We required that patients be followed up for a minimum 3-month period. Unless the clinical model incorporated prior DVT, studies were excluded if patients with a history of prior DVT were enrolled.Data ExtractionTwo reviewers independently reviewed and abstracted data for estimating the prevalence of DVT, sensitivity, specificity, and likelihood ratios (LRs) of D-dimer in each of the 3 clinical probability estimates. Data for the D-dimer in all studies were pooled and analyzed as high-sensitivity/low-specificity test or a moderate-sensitivity/moderate-specificity test.Data SynthesisFourteen studies involving more than 8000 patients used 1 clinical prediction rule for diagnosing DVT, of which 11 incorporated D-dimer testing in the diagnostic algorithm. The prevalence of DVT in the low, moderate, and high clinical probability groups was 5.0% (95% CI, 4.0%-8.0%), 17% (95% CI, 13%-23%), and 53% (95% CI, 44%-61%), respectively. The overall prevalence of DVT was 19% (95% CI, 16%-23%). Pooling all studies, the sensitivity, specificity, and negative LRs of D-dimer testing in the low probability group were 88% (95% CI, 81%-92%), 72% (95% CI, 65%-78%), and 0.18% (95% CI, 0.12-0.18); in the moderate probability group: 90% (95% CI, 80%-95%), 58% (95% CI, 49%-67%), and 0.19% (95% CI, 0.11-0.32); and in the high probability group: 92% (95% CI, 85%-96%), 45% (95% CI, 37%-52%), and 0.16% (95% CI, 0.09-0.30). The LRs for a normal result on a high or moderately sensitive D-dimer assay among patients with: (1) low clinical suspicion were 0.10 (95% CI, 0.03-0.37) and 0.20 (95% CI, 0.12-0.31); (2) moderate clinical suspicion were 0.05 (95% CI, 0.01-0.21) and 0.23 (95% CI, 0.13-0.39); and (3) high clinical suspicion were 0.07 (95% CI, 0.03-0.18) and 0.15 (95% CI, 0.10-0.38).ConclusionsDiagnostic accuracy for DVT improves when clinical probability is estimated before diagnostic tests. Patients with low clinical probability on the predictive rule have prevalence of DVT of less than 5%. In low-probability patients with negative D-dimer results, diagnosis of DVT can be excluded without ultrasound; in patients with high clinical suspicion for DVT, results should not affect clinical decisions.

Development of a Health-Related Quality-of-Life Questionnaire (PCOSQ) for Women with Polycystic Ovary Syndrome (PCOS)

Abstract: Objective: To develop a self-administered questionnaire for measuring health-related quality of life (HRQL) in women with polycystic ovary syndrome (PCOS). Methods: We identified a pool of 182 items potentially relevant to women with PCOS through semistructured interviews with PCOS patients, a survey of health professionals who worked closely with PCOS women, and a literature review. One hundred women with PCOS completed a questionnaire in which they told us whether the 182 items were relevant to them and, if so, how important the issue was in their daily lives. We included items endorsed by at least 50% of women in the analysis plus additional items considered crucial by clinicians and an important subgroup of patients in a factor analysis. We chose items for the final questionnaire taking into account both item impact (the frequency and importance of the items) and the results of the factor analysis. Results: Over 50% of the women with PCOS labelled 47 items as important to them. Clinicians chose 5 addi...

Systematic reviews : synthesis of best evidence for health care decisions

Abstract: This work is aimed at practitioners who wish to learn more about systematic reviews and how to use them. It discusses their value for different groups, including health care providers, teachers, researchers and policy makers. Systematic reviews are a vital link in the great chain of evidence that stretches from the laboratory bench to the bedside. This book aims to increase understanding of the important role that systematic reviews play in advancing knowledge and motivate more practitiners to conduct their own systematic reviews.

Risk factors for ICU-acquired pneumonia.

Abstract: NOSOCOMIAL pneumonia is a major cause of morbidity and the leading cause of death from hospital-acquired infections among adult patients admitted to intensive care units (ICUs).1 This article summarizes recent studies that evaluate risk factors for ICU-acquired pneumonia in critically ill patients. There are several clinical implications of these studies. Risk factors offer prognostic informationabouttheprobabilityofdeveloping lung infection in individual critically ill patients and in populations of such patients. They help us understand some of the pathophysiologic mechanisms that predispose to pneumonia in this setting. Moreover, these mechanistic insights may lead to the development of effective preventive strategies. Finally, risk stratification can highlight whichpatientsmaybemost likelytobenefit from pneumonia prophylaxis. We searched MEDLINE from 1988 to the present for cohort studies of ICU patients in whom nosocomial pneumonia was diagnosed and that used multiple logistic regression analysis to determine predictors of this condition. Studies using a case-control design were excluded. We defined ICU-acquired pneumonia as lung infection diagnosed in ICU patients managed with or without assisted ventilation and ventilator-associated pneumonia (VAP) as lung infection diagnosed more than 48 hours following endotracheal intubation and mechanical ventilation.

Influence of Airway Management on Ventilator-Associated Pneumonia Evidence From Randomized Trials

Abstract: Objective.—Ventilator-associated pneumonia (VAP) is a serious complication of critical illness, conferring increased morbidity and mortality. Many interventions have been studied to reduce the risk of VAP. We systematically reviewed the influence of airway management on VAP in critically ill patients.Data Sources.—Studies were identified through searching MEDLINE and EMBASE from 1980 through July 1997 and by searching SCISEARCH, the Cochrane Library, bibliographies of primary and review articles, personal files, and contact with authors of the randomized trials.Study Selection.—We selected randomized trials evaluating ventilator circuit and secretion management strategies on the rate of VAP.Data Extraction.—Two investigators independently abstracted key data on design features, the population, intervention, and outcome of the studies.Data Synthesis.—The frequency of ventilator circuit changes and the type of endotracheal suction system do not appear to influence VAP rates (3 trials, none with significant difference; range of relative risks [RRs], 0.84-0.91). However, lower VAP rates may be associated with avoidance of heated humidifiers and use of heat and moisture exchangers (5 trials, only 1 showing a significant difference; range of RRs, 0.34-0.86), use of oral vs nasal intubation (1 trial; RR, 0.52; 95% confidence interval, 0.24-1.13), subglottic secretion drainage vs standard endotracheal tubes (2 trials, 1 showing a significant difference; range of RRs, 0.46-0.57), and kinetic vs conventional beds (5 trials, only 1 showing a significant difference; range of RRs, 0.35-0.78).Conclusions.—Some ventilator circuit and secretion management strategies may influence VAP rates in critically ill patients. Whether these strategies are adopted in practice depends on several factors such as the magnitude and precision of estimates of benefit and harm, as well as access, availability, and costs.

Benefit of heparin in peripheral venous and arterial catheters: systematic review and meta-analysis of randomised controlled trials

Abstract: Objective: To evaluate the effect of heparin on duration of catheter patency and on prevention of complications associated with use of peripheral venous and arterial catheters. Design: Critical appraisal and meta-analysis of 26 randomised controlled trials that evaluated infusion of heparin intermittently or continuously. Thirteen trials of peripheral venous catheters and two of peripheral arterial catheters met criteria for inclusion. Main outcome measures: Data on the populations, interventions, outcomes, and methodological quality. Results: For peripheral venous catheters locked between use flushing with 10 U/ml of heparin instead of normal saline did not reduce the incidence of catheter clotting and phlebitis or improve catheter patency. When heparin was given as a continuous infusion at 1 U/ml the risk of phlebitis decreased (relative risk 0.55; 95% confidence interval 0.39 to 0.77), the duration of patency increased, and infusion failure was reduced (0.88; 0.72 to 1.07). Heparin significantly prolonged duration of patency of radial artery catheters and decreased the risk of clot formation (0.51; 0.42 to 0.61). Conclusions: Use of intermittent heparin flushes at doses of 10 U/ml in peripheral venous catheters locked between use had no benefit over normal saline flush. Infusion of low dose heparin through a peripheral arterial catheter prolonged the duration of patency but further study is needed to establish its benefit for peripheral venous catheters.

Acquired neuromuscular disorders in critically ill patients: a systematic review

Abstract: Objective: To summarize the prospective clinical studies of neuromuscular abnormalities in intensive care unit (ICU) patients. Study identification and selection: Studies were identified through MEDLINE, EMBASE, references in primary and review articles, personal files, and contact with authors. Through duplicate independent review, we selected prospective cohort studies evaluating ICU-acquired neuromuscular disorders. Data abstraction: In duplicate, independently, we abstracted key data regarding design features, the population, clinical and laboratory diagnostic tests, and clinical outcomes. Results: We identified eight studies that enrolled 242 patients. Inception cohorts varied; some were mechanically ventilated patients for ≥ 5 days, others were based on a diagnosis of sepsis, organ failure, or severe asthma while others were selected on the basis of exposure to muscle relaxants, or because of participation in muscle biochemistry studies. Weakness was systematically assessed in two of the eight studies, concerning patients with severe asthma, with a reported frequency of 36 and 70 %, respectively. Electrophysiologic and histologic abnormalities consisted of both peripheral nerve and muscle involvement and were frequently reported, even in non-selected ICU patients. In a population of patients mechanically ventilated for more than 5 days, electrophysiologic abnormalities were reported in 76 % of cases. Two studies showed a clinically important increase (5 and 9 days, respectively) in duration of mechanical ventilation and a mortality twice as high in patients with critical illness neuromuscular abnormalities, compared to those without. Conclusions: Prospective studies of ICU-acquired neuromuscular abnormalities include a small number of patients with various electrophysiologic findings but insufficiently reported clinical correlations. Evaluation of risk factors for these disorders and studies examining their contribution to weaning difficulties and long-term disability are needed.

Tunneling short-term central venous catheters to prevent catheter-related infection: a meta-analysis of randomized, controlled trials.

Abstract: Objective To evaluate the efficacy of tunneling short-term central venous catheters to prevent catheter-related infections. Data sources MEDLINE, EMBASE, conference proceedings, citation review of relevant primary and review articles, personal files, and contact with expert informants. Study selection From a pool of 225 randomized, controlled trials of venous and arterial catheter management, we identified 12 relevant trials and included seven of these trials in the analysis. Data extraction In duplicate, independently, we abstracted data on the population, intervention, outcomes, and methodologic quality. Data synthesis Tunneling decreased bacterial colonization of the catheter by 39% (relative risk of 0.61; 95% confidence interval [CI] of 0.39 to 0.95) and decreased catheter-related sepsis with bacteriologic confirmation by 44% (relative risk of 0.56; 95% CI of 0.31 to 1) in comparison with standard placement. The majority of the benefit in the decreased rate of catheter-sepsis came from one trial at the internal jugular site (relative risk of 0.30, 95% CI of 0.10 to 0.89) and the reduction in risk was not significant when the data from five subclavian catheter trials were pooled (relative risk of 0.71, 95% CI of 0.36 to 1.43). Tunneling was not associated with increased risk of mechanical complications from placement or technical difficulties during placement. However, this outcome was not rigorously evaluated. Conclusions Tunneling decreases central venous catheter-related infections. However, current evidence does not support routine tunneling until its efficacy is evaluated at different placement sites and relative to other interventions.

Frequency and methodologic rigor of quality-of-life assessments in the critical care literature.

Abstract: Objectives To present a framework for describing/measuring quality of life (QOL) and health-related quality of life (HRQL), and to assess the frequency and methodologic rigor of QOL studies in the adult critical care literature. Data sources Computerized bibliographic search of published research, manual search of key intensive care unit (ICU) journals, and citation review of relevant articles. Study selection We manually searched Critical Care Medicine, American Journal of Respiratory and Critical Care Medicine, and Intensive Care Medicine for the period January 1992 to July 1995 to assess the frequency of published QOL studies. Combined with a computerized bibliographic search, we found 64 studies that met our criteria that reported on patient-related outcomes (other than mortality) after hospital discharge. Data extraction We abstracted data on the nature of each study, the instruments used to measure QOL, and the methodologic rigor of the QOL assessments. We evaluated each study using criteria we developed to assess the validity of HRQL measurements. Measurements and main results In our manual search, we found 1,073 articles relevant to the practice of adult critical care. Of these, 19 (1.7%)/1073 included QOL measurements. Combined with our comprehensive search strategy, we found 64 papers that evaluated QOL in ICU patients. These papers dealt primarily with issues of: prognosis (32 [50%]), resource allocation (23 [36%]), and clinical prediction (9 [14%]). We found no randomized trials that included post-ICU QOL as an outcome. With respect to the validity of the HRQL assessments, 63/64 (98%) studies evaluated aspects of patients' lives that we considered important. Thirty-three (52%) studies were limited in scope to specific aspects of HRQL, and 31 (48%) studies covered broad areas of HRQL. In these 64 studies, there were 108 different instruments used. The reliability and validity of the instruments used were reported in 7 (6%) and 15 (14%) cases, respectively. For 81 (75%) instruments, the investigators either explained the results or used informative, qualitative descriptors whose interpretation was self-evident. Overall, three (5%) of the included studies met all four methodologic criteria to assess the validity of HRQL assessments. Conclusions QOL assessments occur infrequently in the ICU literature and are of limited methodologic quality. More studies using valid and reliable instruments are necessary to document the long-term QOL of critically ill patients, especially those at risk of a "poor" outcome.

Confidence in life-support decisions in the intensive care unit: A survey of healthcare workers

Abstract: ObjectiveTo examine the relationship between intensive care unit (ICU) healthcare workers' confidence and their decision to withdraw life support.DesignCross-sectional survey of Canadian intensivists, ICU housestaff, and bedside nurses. Respondents chose the level of care (from comfort measures only

The use of glycopyrrolate in a case of intermediate syndrome following acute organophosphate poisoning

Abstract: This report describes a case of organophosphate intoxication refractory to atropine in which glycopyrrolate was used to reduce cholinergic symptoms, and describes the development of intermediate syndrome, an uncommon subacute complication of organophosphate poisoning. A 44-yr-old woman presented in cholinergic crisis following malathion ingestion. Treatment was initiated with atropine and pralidoxime. Despite clinical signs of adequate atropinisation, the patient continued to have profuse bronchorrhoea, which resolved with glycopyrrolate. During her course in the intensive care unit, she displayed a subacute deterioration in neuromuscular and mental status with decrement-increment phenomenon on electromyography consistent with intermediate syndrome. The patient eventually made a complete recovery. This case report describes the successful use of glycopyrrolate in organophosphate intoxication and the development of the intermediate syndrome, characterised by onset of weakness of neck flexors, proximal limb muscles, and respiratory muscles within one to four days after poisoning. Recognition of the syndrome is important in light of the potential for respiratory depression requiring ventilatory support.

Antisecretory Therapy for Bleeding Peptic Ulcer

Abstract: Specific interventions included in the review Proton pump inhibitors (PPIs) (omeprazole (either 80 mg bolus, then 40 mg IV every 8 hours for 24 hours then 40 mg orally every 12 hours, or 80 mg bolus then 40 mg IV every 12 hours or every 8 hours, or 40 mg bolus then 6.7 mg/hour IV, or 40 mg orally every 12 hours)) for the intervention group and placebo or ranitidine (50 mg IV every 4 hours or 6 hours) or cimetidine (50 mg/hour IV) in the control groups.

A cross-cultural comparison of attitudes towards life support limitation in Sweden and Canada

Abstract: Objective: To compare the attitudes of intensive care unit (ICU) healthcare workers towards withholding and withdrawing life support in Sweden and Canada Design: Nationwide surveys in two countries Setting: ICUs in 49 university-affiliated and/or tertiary referral hospitals Participants: Intensive care physicians and nurses Interventions: None Measurements and main results: The response rates were 1,361/1,795 (76%) for Canada and 846/1,081 (78%) for Sweden Respondents chose between five levels of care, ranging from comfort measures to full intensive care, in two of 12 different clinical scenarios Taking all other variables into account, Swedish healthcare workers chose more aggressive levels of care than did their Canadian colleagues, the difference in mean level of care being 038 on a five-point scale Conclusions: Healthcare personnel in countries sharing a common cultural heritage and with similar healthcare funding differ in attitudes towards end-of-life issues

How to use practice guidelines in the intensive care unit: Diagnosis and management of unstable angina.

Abstract: Objective: Practice guidelines are often based on expert opinion, and are sometimes based on research evidence, but are usually a mix of both. The goal of this article is to aid in the evaluation of the validity of practice guidelines. Data Synthesis: The Agency for Health Care Policy and Research Practice Guideline on Management of Unstable Angina and other relevant primary and synthetic research. Methods: Critical appraisal ot guidelines requires understanding how guideline developers identified, appraised, and summarized the evidence, and how they chose the values reflected in their recommendations. To determine whether guidelines are applicable in our practice, we look for clear and concise recommendations about specific populations, describing common options linked to clinically important outcomes. Guidelines must be considered in light of local skills, culture, and resources, and need to be individualized to different patients and settings. Conclusions: As better evidence and new clinical insights emerge, guidelines require updating. The ultimate value of a guideline is determined by evaluating its effect on process of care, resource utilization, and most importantly, patient outcomes.

How to use a review article : Prophylactic endoscopic sclerotherapy for esophageal varices

Abstract: Objective To assess the validity of a meta-analysis about sclerotherapy for the primary prevention of bleeding from esophageal varices, to interpret the results, and discuss whether they apply in practice. Data Sources Critical appraisal techniques for systematic reviews. Data Extraction Systematic reviews are distinct from narrative reviews in that they answer specific clinical questions, and have explicit and reproducible methods for searching, selecting, and appraising the primary studies, to create the most valid synthesis of the evidence. Data Synthesis Meta-analyses are systematic reviews containing a critical appraisal and statistical summary of individual study results and their confidence limits, whereas qualitative systematic reviews provide a narrative executive summary of study results. Conclusions High-quality systematic reviews are being used increasingly to guide practice, strengthening the link between research results and improved health outcomes. Understanding their strengths and limitations helps us to use them appropriately in practice. (Crit Care Med 1998; 26:692-700)

Systematic review: Intra-aortic balloon counterpulsation pump therapy: a critical appraisal of the evidence for patients with acute myocardial infarction

Abstract: Intra-aortic balloon counterpulsation pump (IABP) therapy has been used in several clinical situations, predominantly in critically ill patients, since 1968 [1]. In acute myocardial infarction (AMI) patients who are experiencing continued ischemia, IABP therapy may be used in an attempt to improve patency of an infarct-related coronary artery (IRA) and reduce the rates of recurrent myocardial ischemia and its sequelae. The mechanism for this benefit is thought to be a combination of reduced oxygen demand [2], increased coronary artery blood flow velocity [3], and augmentation of diastolic arterial pressure enhancing thrombolysis, leading to faster reperfusion [4]. IABP therapy may also be used in patients with ventricular septal rupture, severe mitral regurgitation, and cardiogenic shock. The technique for IABP therapy involves insertion of an 8 or 9.5 Fr helium-filled balloon via the femoral artery into the descending aorta. The device is preferably inserted through an existing vascular access site in an attempt to reduce the rate of vascular and hemorrhagic complications. It is crucial that the tip be positioned distal to the left subclavian artery, but proximal to the renal arteries. The balloon is synchronized to deflate during early systole, thus decreasing left ventricular (LV) afterload. In turn, LV ejection fraction (EF) and stroke volume (SV) are enhanced, leading to reduced myocardial oxygen consumption. The balloon inflates during early diastole, thus increasing coronary blood flow and peripheral perfusion. The IABP is usually commenced at a rate of 1 : 1. Once the benefit of IABP therapy is thought to be concluded, patients are usually gradually weaned from the pump at rates of 1 : 2 to 1 : 3 over 6-12 h. Following the procedure, one must ensure that the patient has adequate radial artery pulses, suggesting no IABP interference with the subclavian arteries. A chest roentgenogram should be inspected for the location of the IABP marker, which should be 1-2 cm below the aortic arch knuckle. The patient's serum creatinine and urine output should be followed for evidence of IABP interference with the renal arteries. When used to prevent recurrent ischemia post-AMI, all patients who receive IABP therapy should also be prescribed daily aspirin and systemic heparinization with 1000-2000 U/h infused for at least 48 h to maintain activated partial thromboplastin time (aPTT) between 50 and 84 s. Contraindications to IABP use include severe peripheral vascular disease (PVD), defined as diminished femoral pulses or absent pedal pulses; aortic valve regurgitation (AVR); aortic dissection; tortuous or aneurysmal descending thoracic or abdominal aorta; and patients unable to be systemically heparinized. IABP therapy does not prohibit the use of other medications often used in AMI patients, including aspirin, systemic heparinization, angiotensin-converting enzyme inhibitors, intravenous nitroglycerine, and beta blockers. Complications of IABP therapy may include limb ischemia and hemorrhage to the femoral access site. A recently developed technique of sheathless insertion may reduce the rate of limb ischemia [5].

Research in the Intensive Care Unit

Abstract: Biomedical research seeks to apply insights gleaned from the study of biologic processes to the clinical care of the ill—a model alliteratively embodied in the concept of bench to bedside investigation. Nowhere is the distance from the laboratory bench to the bedside shorter than in the contemporary intensive care unit (ICU). The management of the critically ill patient can legitimately be seen as a continuous experiment in applied physiology. The monitoring of physiological processes in the ICU enables the intensivist to generate hypotheses regarding cause, to test them through therapeutic intervention, and to support or reject them through continuing evaluation of clinical response.