The effect of copper-oxide-treated soft and hard surfaces on the incidence of healthcare-associated infections: a two-phase study

BACKGROUND

Copper-oxide-impregnated linens and hard surfaces within the hospital environment have emerged as a novel technology to reduce environmental contamination and thereby potentially reduce the risk of healthcare-associated infections (HCAIs).

METHODS

This was a two-phase study. Phase 1 was a prospective, cluster-randomized, cross-over clinical trial in which one pod (eight beds) of our general ICU (GICU) utilized copper-oxide-impregnated linens whereas the other pod (eight beds) used standard hospital linens. Phase 2 was a two-year before-after study, following the relocation of three ICUs into a new ICU tower in which all the hard surfaces were treated with copper oxide (in addition to copper-impregnated linens). HCAIs were recorded using the National Healthcare Safety Network definitions.

FINDINGS

A total of 1282 patients were enrolled in phase 1. There was no difference in the rate of HCAI between the patients who received standard compared with copper oxide linen. In phase 2 there was a significant reduction in the number of infections due to Clostridioides difficile (2.4 per 1000 vs 0.7 per 1000 patient-days; incidence rate ratio: 3.3; 95% confidence interval: 1.4-8.7; P = 0.002) but no difference in the rate of central-line-associated bloodstream infections nor of catheter-associated urinary tract infections.

CONCLUSION

Copper-oxide-impregnated linens alone had no effect on the rate of HCAI. Our data suggest that copper-oxide-treated hard surfaces reduced the rate of infections due to C. difficile; however, important confounders cannot be excluded.

The clinical characteristics and hospital and post-hospital survival of patients with the obesity hypoventilation syndrome: analysis of a large cohort

OBJECTIVE

The worldwide prevalence of obesity has reached epidemic proportions. Obesity hypoventilation syndrome (OHS) is a common yet largely undiagnosed and mistreated condition that likely carries a high mortality. The aim of this study was to determine the clinical characteristics, hospital outcome, outcome following hospital discharge and predictors of death in a large cohort of patients hospitalized with OHS. OHS is an important condition as many patients with this syndrome are misdiagnosed and receive inappropriate treatment.

METHODS

We reviewed the electronic medical records of patients with unequivocal OHS admitted to a 525-bed tertiary-care teaching hospital over a 5-year period. Demographic and clinical data as well as hospital disposition were recorded. In order to determine the patients' post-discharge status, we linked our database to the database of death certificates of the State Registrar of Vital Records.

RESULTS

We identified 600 patients who met the inclusion criteria for this study. The patients' mean age was 58 ± 15 years with a mean body mass index of 48.2 ± 8.3 kg m-2; 64% were women. Thirty-seven percent had a history of diabetes and 43% had been misdiagnosed as having chronic obstructive pulmonary disease, while none had been previously diagnosed with OHS. The most common admission diagnoses were respiratory failure, heart failure and sepsis. Ninety (15%) patients died during the index hospitalization. The patients' age, S-creatinine, respiratory failure, sepsis and admission to the ICU were independent predictors of hospital mortality. The hospital survivors were followed for a mean of 1,174 ± 501 d (3.2 ± 1.3 years) from the index hospitalization. On follow-up, 98 of the 510 (19%) hospital survivors died, with an overall cumulative mortality of 31.3%. The patients' age, S-creatinine and admission to the ICU were independent predictors of post-hospital mortality.

CONCLUSION

Obesity hypoventilation syndrome is a common disease that is frequently misdiagnosed and mistreated and carries a 3-year morality, which is significantly worse than that for most cancers combined. Considering the high mortality of this disease, all patients with a body mass index > 35 kg m-2 should be screened for OHS; those patients with both early and established OHS should be referred to a pulmonary and/or sleep specialist for evaluation for non-invasive positive pressure ventilation, to a dietician for dietary counseling and lifestyle modification and to a bariatric surgeon for evaluation for bariatric surgery.

The malignant obesity hypoventilation syndrome (MOHS)

We have coined the term 'malignant obesity hypoventilation syndrome' (MOHS) to describe a severe multisystem disease due to the systemic effects of obesity. Patients with this syndrome have severe obesity-related hypoventilation together with systemic hypertension, diabetes and the metabolic syndrome, left ventricular hypertrophy with diastolic dysfunction, pulmonary hypertension and hepatic dysfunction. This syndrome is largely unrecognized as physicians do not make the association between the patients' multiple medical problems and obesity. Because of the delayed diagnosis and progressive morbidities of this condition, all patients with a body mass index of more than 40 kg m(-2) should be screened for MOHS. The management of patients with MOHS includes short-term measures to improve the patients' medical condition and long-term measures to achieve enduring weight loss. Bariatric surgery reverses or improves the multiple metabolic and organ dysfunctions associated with MOHS and should be strongly considered in these patients.

Immunonutrition in the surgical patient

Both malnutrition and the physical injury related to trauma and surgery increase the expression of T-helper 2 (Th2) lymphocytes which cause impaired cell mediated immunity. Activation of the hypothalamic-pituitary-adrenal axis and sympathoadrenal system with the release of cortisol and catecholamines drive the development of Th2 cells. Th2 cytokines result in the accumulation of arginase-1 expressing myeloid-derived suppressor cells in lymphoid tissue. The myeloid-derived suppressor cells cause an arginine deficient state resulting in impaired lymphocyte function. Prostaglandin-E2 released following trauma plays a synergetic role with cortisol and catecholamines in driving these pathways. There is now increasing evidence that immunomodulating enteral formulas supplemented with arginine and omega-3 fatty acids can reverse many of the immune mediated changes and decrease the number of adverse outcomes after major surgery and trauma. These immunomodulating enteral formulas should be strongly considered in surgical patients undergoing major surgery and following severe trauma.

Low-dose dopamine: a systematic review

OBJECTIVE

To determine the magnitude of the treatment effect of low-dose dopamine on renal function in patients at risk of and in patients with early renal injury.

DATA SOURCES

MEDLINE, citation review of relevant primary and review articles, personal files, and contact with expert informants.

STUDY SELECTION

Randomized controlled studies that compared low-dose dopamine with placebo for the prevention or treatment of acute renal dysfunction. From 122 articles screened, 21 met the inclusion criteria for this meta-analysis. Of these six, were excluded.

DATA EXTRACTION

Fifteen studies containing 970 subjects were analyzed. Descriptive and outcome data were extracted. The main outcome measure was the absolute change in serum creatinine. In addition the number of patients who developed an acute decline in renal function was recorded. The meta-analysis was performed using the random effects model.

DATA SYNTHESIS

The meta-analysis demonstrated no significant difference between the absolute change in serum creatinine (5.1 micromol/l, 95% CI of -6.5 to +16.7) and the incidence of acute renal dysfunction (31% vs 33%, relative risk 1.01, 95% CI of 0.79-1.28) between those patients receiving low-dose dopamine and the control group. In addition, no sub-group of patients showed improved renal function with low-dose dopamine.

CONCLUSIONS

The results of this meta-analysis confirms that low-dose dopamine has no reno-protective effect. Considering the potential side-effects of dopamine this agent should not be used for this indication.

Early enteral nutrition in acutely ill patients: a systematic review

OBJECTIVE

To evaluate the effect of early enteral nutrition on the outcome of critically ill and injured patients.

DATA SOURCES

MEDLINE, citation review of relevant primary and review articles, personal files, and contact with expert informants.

STUDY SELECTION

Randomized, controlled studies that compared early with delayed enteral nutrition in hospitalized adult postoperative, trauma, head-injured, burn, or medical intensive care unit (ICU) patients. From 161 articles screened, 27 were identified as randomized, controlled trials comparing early with delayed enteral nutrition and were included for data extraction. Of these, 12 were excluded. None of the studies included medical ICU patients.

DATA EXTRACTION

Fifteen studies containing 753 subjects were analyzed. Descriptive and outcome data were extracted independently from the articles by the two reviewers. Main outcome measures were infections, noninfectious complications, length of hospital stay, and mortality. The meta-analysis was performed using the random effects model.

DATA SYNTHESIS

Early enteral nutrition was associated with a significantly lower incidence of infections (relative risk reduction, 0.45; 95% confidence interval, 0.30-0.66; p =.00006; test for heterogeneity, p =.049) and a reduced length of hospital stay (mean reduction of 2.2 days; 95% confidence interval, 0.81-3.63 days; p =.004; test for heterogeneity, p =.0012). There were no significant differences in mortality or noninfectious complications between the two groups of patients.

CONCLUSIONS

The results of this meta-analysis support the experimental data demonstrating the benefit of the early initiation of enteral nutrition. The results of this meta-analysis must, however, be interpreted with some caution because of the significant heterogeneity between studies.

Sublingual capnography: a clinical validation study

OBJECTIVE

To compare sublingual PCO(2) (PslCO(2)) measurements with gastric intramucosal PCO(2) (PimCO(2)) as well as with the traditional indexes of tissue oxygenation in hemodynamically unstable ICU patients.

DESIGN

A prospective, validation study.

SETTING

The medical and coronary ICUs of a community teaching hospital.

PATIENTS

Consecutive patients with severe sepsis, septic shock, or cardiogenic shock requiring pulmonary artery catheterization for hemodynamic management.

INTERVENTIONS

During the first 24 h of ICU admission, the PslCO(2), PimCO(2), and blood lactate concentrations as well conventional hemodynamic and oxygenation parameters were recorded every 4 to 6 h. The PslCO(2)-PaCO(2) and PimCO(2)-PaCO(2) differences were used as indexes of tissue dysoxia. These variables were correlated with each other as well as with the traditional markers of tissue oxygenation.

RESULTS

Seventy-six data sets were obtained on 22 patients. Fifteen patients had severe sepsis/septic shock, and 7 patients did not have sepsis. A patient with ischemic bowel who had a large PimCO(2)-PslCO(2) difference (60.2 mm Hg) was excluded. The initial PslCO(2) and PimCO(2) measurements were 43.5 +/- 10.4 mm Hg and 42.8 +/- 10.9 mm Hg, respectively (correlation coefficient [r] of 0.86; p < 0.001). The mean PslCO(2) and PimCO(2) for the entire data set were 48.0 +/- 13.4 mm Hg and 46.1 +/- 12.3 mm Hg, respectively (r = 0.78; p < 0.001). Ten patients died. The initial PslCO(2)-PaCO(2) difference was 9.2 +/- 5.0 mm Hg in the survivors and 17.8 +/- 11.5 mm Hg in the nonsurvivors (p = 0.04). The initial PimCO(2)-PaCO(2) difference was 8.4 +/- 4.8 mm Hg in the survivors and 16.1 +/- 13.7 mm Hg in the nonsurvivors (p = 0.08, not significant). The initial PslCO(2)-PaCO(2) difference correlated with the initial mixed venous-arterial CO(2) gradient (r = 0.66; p = 0.001), but correlated poorly with the initial blood lactate concentration (r = 0.38), mixed venous PO(2) (r = 0.05), and systemic oxygen delivery (r = - 0.39).

CONCLUSION

In this study, sublingual capnometry yielded measurements that correlated well with those of gastric tonometry. PslCO(2) may serve as a technically simple and noninvasive clinical measurement of tissue dysoxia in critically ill and injured patients.

Influenza pneumonia: a descriptive study

OBJECTIVE

To describe the clinical features and complications of patients hospitalized with influenza during the 1999-2000 influenza season.

METHODS

We reviewed all cases of patients with influenza admitted to a large metropolitan referral hospital during the 1999-2000 season.

RESULTS

Thirty-five adult patients (15 men and 20 women) tested positive for influenza A by direct enzyme immunoassay. A fourfold to sevenfold increase in the number of influenza cases was observed over previous years. Most patients had serious comorbid illnesses (88%), such as diabetes and chronic respiratory and heart disease. Seventeen patients developed pneumonia; these patients tended to be older (mean +/- SD, 63 +/- 13 years vs 51 +/- 19 years, respectively; p = 0.04) and had a higher incidence of chronic lung disease (41% vs 6%, respectively; p = 0.02) than the patients without pneumonia. Shortness of breath was the only symptom that distinguished patients with pneumonia from those with an upper respiratory tract illness alone. Antiviral treatment was begun 4 +/- 3 days from initiation of symptoms in patients with pneumonia and consisted of oseltamivir (35.2%), rimantadine (5.8%), or a combination of both (17.6%). Respiratory and/or blood culture results were positive in five patients (29%), Staphylococcus aureus was isolated in five patients, and Streptococcus pneumoniae was isolated in one patient. Ten of the patients with pneumonia (58.8%) were admitted to the ICU, and 5 patients (29%) died. The length of ICU stay and mechanical ventilation were 28 +/- 26 days and 21.5 +/- 20.5 days, respectively. Death in most pneumonia patients was attributed to respiratory failure.

CONCLUSION

The recognized number of hospital admissions for influenza increased fourfold to sevenfold over previous years, most likely due to the implementation of rapid diagnostic tests for influenza. Patients with signs and symptoms of influenza and shortness of breath should undergo chest radiography. Hospitalization of patients with influenza pneumonia occurred in both previously healthy and immunocompromised patients and had a high mortality. S aureus was the most common bacterial isolate in patients with influenza pneumonia. Empiric antibiotics with staphylococcal activity should be used pending culture results in patients with influenza pneumonia. The effectiveness of oseltamivir and rimantadine in treating patients with influenza pneumonia remains to be determined.

CPR in terminally ill patients?

While limiting and foregoing therapy at the end of life is now accepted on medical, ethical, moral and legal grounds, many Americans continue to die with heroic measures being taken to prevent their death. When the patient does eventually die, attempts are frequently made to revive the patient by performing cardiopulmonary resuscitation (CPR). While CPR may result in the establishment of a perfusing pressure, in almost all instances, the patient succumbs despite advanced life support technology. The widespread adoption of do-not-resuscitate (DNR) protocols has not prevented CPR from being performed on patients, who are unlikely to survive. We present two cases, which highlight the modern American way of dying. We submit that poor end-of-life care may result from physicians discomfort with death, their poor communication skills and their failure to fully comprehend the benefits and limitations of advanced life support technology. Furthermore, we maintain that CPR should only be performed on patients, who are likely to derive benefit from this intervention.

The effect of aging on circulating levels of proinflammatory cytokines during septic shock. Norasept II Study Investigators

BACKGROUND

As the proportion of the population that is older continues to rise, infection in older people has become an important healthcare problem. Although aging is associated with multiple abnormalities in immune function, the effect of aging on the production of proinflammatory cytokines has not been well studied under conditions of clinical stress.

OBJECTIVES

The aim of this study was to examine the effect of aging on circulating levels of the proinflammatory cytokines in a large cohort of septic shock patients. We hypothesized that aging would be associated with a diminished proinflammatory cytokine response to sepsis.

DESIGN

Patients with septic shock who were enrolled in the placebo limb of the North American Sepsis Trial (NORASEPT II) study were analyzed.

SETTING

The intensive care units of 105 hospitals in the United States and Canada.

PARTICIPANTS

Nine hundred and thirty patients presenting to hospital within 12 hours of the onset of septic shock.

MEASUREMENTS

Interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), soluble tumor necrosis factor-receptor-55 (sTNF-R55), and soluble tumor necrosis factor-receptor-75 (sTNF-R75) concentrations were measured at enrollment. The study population was broken down into five age groups as follows: less than 50 years (group one), 50 to 64 years (group two), 65 to 74 years (group three), 75 to 84 years (group four), and 85 or older (group five). Clinical, demographic, and cytokine data were extracted to describe each age group.

RESULTS

Data were available for 930 patients. The patients' mean age (+/- SD) was 59 +/- 17 years (range, 18 to 102). There were 280 patients in group one, 242 in group two, 210 in group three, 150 in group four, and 48 in group five. The primary diagnoses; clinical characteristics; and IL-6, sTNF-R55, and sTNF-R75 levels were similar among the five age groups. The TNF-alpha levels were significantly higher, however, in the oldest group of patients (group five). The 28-day survival was 49% in patients over the age of 75 and 58% in those under 75 years (P = .03). There was no gender difference in survival or cytokine levels.

CONCLUSIONS

Contrary to our expectations, we found that aging was not associated with a decline in the circulating levels of proinflammatory cytokines.

The clinical features of severe community-acquired pneumonia presenting as septic shock. Norasept II Study Investigators

PURPOSE

The purpose of this article was to determine the outcome, clinical and prognostic features, and microbiology of a large group of patients with community-acquired pneumonia (CAP) presenting in septic shock.

MATERIALS AND METHODS

The placebo limb of the Norasept II database was examined. Data were collected on patients in septic shock with a diagnosis of CAP who presented to a participating site from home.

RESULTS

One hundred and forty-eight patients met the study criteria. The 28-day survival was 53%. One hundred and four pathogens were isolated from 77 (52%) patients with 24 (16%) patients having polymicrobial infections. The most common pathogen was Streptococcus pneumoniae (19%), followed by Staphylococcus aureus (18%), Haemophilus influenzae (14%), Klebsiella pneumoniae (11%), and Pseudomonas aeruginosa (7%). Infection with P aeruginosa or Acinetobacter species carried a very high mortality (82%). The only clinical variables recorded in the database that could identify patients with pseudomonas or acinetobacter infection was a history of alcohol abuse. Comorbidities were present in 74% of patients, involving predominantly the cardiorespiratory system. Logistic regression analysis demonstrated APACHE II score and serum interleukin 6 (IL-6) concentration to be significant independent predictors of mortality. Patients with pseudomonas or acinetobacter infection had significantly higher IL-6 levels and significantly lower tumor necrosis factor alpha levels when compared with the rest of the cohort of patients.

CONCLUSION

A diverse spectrum of both gram-positive and gram-negative pathogens were implicated in patients with CAP presenting in septic shock, necessitating broad spectrum empiric antimicrobial coverage. This coverage should include antipseudomonal activity, particularly in alcoholic patients. Severity of illness (APACHE II score) and IL-6 levels were important prognostic factors. Infection with P aeruginosa and Acinetobacter species carried a very high mortality.

The diagnosis and management of hypertensive crises

Severe hypertension is a common clinical problem in the United States, encountered in various clinical settings. Although various terms have been applied to severe hypertension, such as hypertensive crises, emergencies, or urgencies, they are all characterized by acute elevations in BP that may be associated with end-organ damage (hypertensive crisis). The immediate reduction of BP is only required in patients with acute end-organ damage. Hypertension associated with cerebral infarction or intracerebral hemorrhage only rarely requires treatment. While nitroprusside is commonly used to treat severe hypertension, it is an extremely toxic drug that should only be used in rare circumstances. Furthermore, the short-acting calcium channel blocker nifedipine is associated with significant morbidity and should be avoided. Today, a wide range of pharmacologic alternatives are available to the practitioner to control severe hypertension. This article reviews some of the current concepts and common misconceptions in the management of patients with acutely elevated BP.

What's in a day? Determining intensive care unit length of stay

OBJECTIVE

Intensive care unit (ICU) length of stay (LOS) and hospital LOS are common indices used to compare performance of hospitals and are yardsticks used in efforts to contain costs, yet there is no standardized method of quantitating this outcome variable. Attempts have been made to correct LOS according to disease severity. The aim of this study was to quantify and compare ICU LOS using four commonly used methods and to determine the relationship between severity of illness at admission as determined by the Acute Physiology and Chronic Health Evaluation (APACHE) II and APACHE III scoring systems and LOS.

DESIGN

Prospective, cohort study.

SETTING

Medical and surgical ICUs of a community teaching hospital.

MEASUREMENTS AND MAIN RESULTS

The demographic and clinical data of all patients admitted to the medical ICU and the surgical ICU during a 6-month period were recorded and stored in a computerized database. Coronary care unit boarders and cardiothoracic patients were excluded from analysis. The date and exact time of all admissions and discharges were abstracted from the patients' flowcharts and nurses' notes. The ICU LOS of all patients was calculated using four common methods: a) number of calendar days (LOS-calendar); b) midnight bed-occupancy days (LOS-midnight); c) exact LOS calculated in hours divided by 24 (LOS-exact); and d) the method described by Pollack and Ruttimann (LOS-Pollack). There were 1,004 admissions during the study period; of these, 254 were excluded from analysis (65 coronary care unit boarders and 189 cardiothoracic patients). Of the remaining 750 admissions, 391 were medical ICU patients and 359 were surgical ICU patients. Mean age was 64 +/- 18 yrs, with 420 (56%) male patients. The LOS-calendar differed significantly from the other three methods (p = .001). The LOS-midnight most closely approximated the LOS-exact. The mean (+/- SD) LOS-exact for the entire cohort of patients was 2.8 +/- 3.9 days, with a geometric mean of 1.6 days and a median of 1.4 days. An analysis of the data distribution showed many outliers with the plot markedly skewed to the right. Log transformation of the LOS-exact revealed a normal distribution. The APACHE II and APACHE III scores were significantly higher and the LOS-exact was nonsignificantly higher in the nonsurvivors. There was a poor correlation among the LOS-exact, log LOS-exact, LOS-exact of survivors, and LOS-exact below upper 95th percentile with the APACHE II and APACHE III scores.

CONCLUSION

We suggest that the LOS-midnight be used to record LOS when a hospital/ICU information system is unable to calculate the exact LOS in hours. Furthermore, because the LOS distribution is highly skewed, the geometric mean and median should be reported. Although APACHE II and APACHE III scores are predictive of group outcomes, they should not be used to predict or adjust for LOS.

Hypothermia and cytokines in septic shock. Norasept II Study Investigators. North American study of the safety and efficacy of murine monoclonal antibody to tumor necrosis factor for the treatment of septic shock

BACKGROUND

Hypothermic patients with sepsis have been reported to have a higher mortality than febrile septic patients. The failure to mount a febrile response in sepsis is poorly understood. Since the proinflammatory cytokines play a crucial role in the genesis of fever, we postulated that hypothermic patients with sepsis would have lower circulating levels of these cytokines than febrile patients.

METHODS

Patients with septic shock who were enrolled into the placebo limb of the North American study of the safety and efficacy of murine monoclonal antibody to tumor necrosis factor for the treatment of septic shock (NORASEPT II) were analyzed. Body temperature, interleukin-6, tumor necrosis factor alpha, soluble tumor necrosis factor receptor-55, and soluble tumor necrosis factor receptor-75 concentrations were measured at enrollment. The study population was divided into a hypothermic (temperature < 35.6 degrees C) and a febrile group (temperature > or = 38.3 degrees C) according to the core temperature at enrollment (normothermia was an exclusion criteria). Clinical, demographic, and cytokine data were extracted, allowing for comparisons between these two groups of patients. In addition, the correlation between the core body temperature and cytokine levels at enrollment was determined.

RESULTS

A complete data set was available for 930 patients; 195 patients (21%) were hypothermic at enrollment. The 28-day survival of these patients was significantly lower than that of the febrile patients (34% vs. 59%, p < 0.001). Hypothermia (and enrollment temperature) were independent predictors of mortality. The hypothermic patients had a higher incidence of organ dysfunction at enrollment than the febrile patients. There was no significant difference in the cytokine profile between the two groups of patients. In addition, there was no correlation between the core body temperature at enrollment and the circulating levels of cytokines measured.

CONCLUSION

Hypothermic patients with septic shock have a significantly higher mortality with a higher incidence of organ dysfunction than febrile septic shock patients. The hypothermia in these patients cannot be explained by lower levels of circulating proinflammatory cytokines.

Fever in the ICU

Fever is a common problem in ICU patients. The presence of fever frequently results in the performance of diagnostic tests and procedures that significantly increase medical costs and expose the patient to unnecessary invasive diagnostic procedures and the inappropriate use of antibiotics. ICU patients frequently have multiple infectious and noninfectious causes of fever, necessitating a systematic and comprehensive diagnostic approach. Pneumonia, sinusitis, and blood stream infection are the most common infectious causes of fever. The urinary tract is unimportant in most ICU patients as a primary source of infection. Fever is a basic evolutionary response to infection, is an important host defense mechanism and, in the majority of patients, does not require treatment in itself. This article reviews the common infectious and noninfectious causes of fever in ICU patients and outlines a rational approach to the management of this problem.

Physicians' own preferences to the limitation and withdrawal of life-sustaining therapy

While limiting and forgoing therapy at the end of life is now accepted on medical, ethical, moral and legal grounds, many Americans continue to die with heroic measures being taken to prevent their death. Recent studies have demonstrated that physicians frequently attend to their patients without knowledge of their preferences with regards to end-of-life issues. It is postulated that a physician's personal preferences with regard to the limitation and withdrawal of life support and active euthanasia would effect the discussion they had with their patients. The purpose of this study was to analyze end-of-life preferences of a diverse group of practicing physicians. The participants were active attending physicians at a community hospital, a rural referral center, a large tertiary care referral academic complex, and a specialized tertiary care referral center all within the United States. A questionnaire was developed which was mailed to attending physicians at the four participating medical centers. The respondents provided basic demographic data, do-not-resuscitate (DNR) preferences under various clinical circumstances as well as responses to a number of case vignettes. Six hundred and forty physicians responded to the survey. The mean age of the respondents was 46 years; 72% were male. In the event of a cardiac arrest less than 20% of respondents would want to undergo cardiopulmonary resuscitation in the setting of chronic end stage organ failure; the positive response rate was 5% for metastatic cancer and 2% for Alzheimer's disease. If death was imminent, 87% of physicians indicated they would want treatment withdrawn. Similarly, 95% of respondents indicated that they would want treatment withdrawn should they be in a persistent vegetative state. Only 1% of respondents believed that health care providers should never remove or withhold life-sustaining therapy. Should they have advanced motor neuron disease, 38% of physicians indicated they would request that their life be ended. The majority of physicians surveyed volunteered that they would want life-sustaining measures to be limited at the end of their life. A significant number were in favor of active euthanasia. This study suggests that it is unlikely that physicians' personal beliefs in regards to end-of-life care result in the failure to discuss these issues with their patients.

Pulmonary artery catheterization and esophageal doppler monitoring in the ICU

The clinical assessment of cardiac performance and ventricular preload is notoriously unreliable in critically ill patients. Consequently, a number of technologies have been developed to provide the clinician with indexes of cardiovascular function to assist in therapeutic decision making. Foremost among these is the pulmonary artery catheter (PAC). Indeed, the PAC has largely shaped the practice of modern critical care. Yet, the information provided by the PAC is largely misunderstood, and its efficacy is never proven. Recently, continuous esophageal Doppler monitoring has emerged as an alternative to pulmonary artery catheterization. This paper evaluates the clinical utility of the PAC and esophageal Doppler monitoring in assessing the hemodynamic status of ICU patients.

Automatic external defibrillators: lessons from the past, present and future

Coronary artery disease remains the leading cause of death in the United States and most developed countries. Many of the victims die from sudden cardiac arrests, resulting from dysrhythmias-most commonly ventricular fibrillation. Since most cardiac arrests occur outside the hospital, implementing emergency services in the field will have a great impact on survival. With the development of the modern automatic external defibrillator (AED), early recognition and correction of these dysrhythmias by lay rescuers can significantly improve outcome from sudden death. This paper reviews the past, present and future development and applications of AEDs.

Critical care and the World Wide Web

The Internet was created in 1969, when the Advanced Research Projects Agency of the United States Department of Defense fired up an experimental network consisting of only four computers. Over the past five years there has been an exponential explosion in the number of computers added to this network. It is estimated that Internet traffic doubles every 100 days with more than 100 million people worldwide now on-line. The Internet is so vast that practically every aspect of human interest is represented is some form or fashion. From recreation to applied science and technology, and from Critical Care Medicine case scenarios to digitized radiology images and pathology specimens, the Internet has become increasingly useful for critical care practitioners. To date, no resource is better equipped to assist critical care providers in many of their daily tasks. This article presents some of the historical developments of the Internet as well as common applications that are useful for critical care practitioners.

Severity scoring and outcome assessment. Computerized predictive models and scoring systems

Severity of illness scoring systems and standardized death ratios are being used with increasing frequency as markers of quality of care and to compare and contrast the performance of ICUs. However, numerous factors unrelated to the quality of care delivered may impact the severity of illness score and standardized death ratios. This article reviews the commonly used severity scoring systems and factors that affect their predictive performance.

The ex vivo antimicrobial activity and colonization rate of two antimicrobial-bonded central venous catheters

OBJECTIVE

Catheter-related sepsis is an important complication associated with the use of central venous catheters. Recent studies have suggested that antimicrobial-bonded catheters may reduce catheter colonization and catheter-related sepsis. The aim of this study was to determine the relationship between the antimicrobial activity and the colonization rate of two commercially available antimicrobial-bonded central venous catheters.

DESIGN

Prospective, randomized, controlled, nonblinded study.

SETTING

Medical intensive care unit of a university-affiliated teaching hospital.

PATIENTS

One hundred twenty consecutive medical intensive care unit patients requiring new central venous catheters (fresh stick).

INTERVENTIONS

Patients were randomized to receive a) a Standard Arrow; b) an ARROWgard; or c) a Cook Bio-Guard Spectrum central venous catheter. Central venous catheters were removed when they were no longer required or when catheter-related sepsis was suspected. Under aseptic conditions, the distal 12 cm of the removed catheters were cut into six 2-cm segments. Semiquantitative culture was performed (by roll technique) on the distal segment. Colonization was defined as >15 colony-forming units. Using a modified Kirby-Bauer technique, the zone of inhibition of the remaining five segments was determined against the following organisms: methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, Enterococcus faecalis, Acinetobacter baumannii, and Candida albicans Catheters that were removed within 24 hrs of insertion were excluded from the analysis.

MEASUREMENTS AND MAIN RESULTS

Seven patients were not assessable. The baseline clinical and demographic characteristics were similar among the three groups of patients. Eleven Standard Arrow (28%), seven ARROWgard (19%), and four Bio-Guard (11%) catheters were colonized (p = .05 for Bio-Guard vs. control). Staphylococci were the most common colonizing organisms. Two patients with Standard Arrow catheters (5%) and one patient with an ARROWgard catheter (3%) developed catheter-related sepsis. Antibiotic-coated catheters significantly inhibited the growth of all test organisms except C. albicans (p < or = .05). Zones of inhibition were significantly larger for the Bio-Guard compared with the ARROWgard catheter when tested against MRSA, S. epidermidis, and E. faecalis (p < or = .002).

CONCLUSION

The Bio-Guard central venous catheter had greater ex vivo antimicrobial activity against MRSA, S. epidermidis, and E. faecalis compared with the ARROWgard catheter, and this was associated with a significantly lower rate of catheter colonization.

Severe systemic inflammatory response syndrome with shock and ARDS resulting from Still's disease: clinical response with high-dose pulse methylprednisolone therapy

Adult-onset Still's disease, the adult variant of the systemic form of juvenile arthritis, is an uncommon systemic inflammatory disorder of unknown etiology characterized by high spiking fevers, neutrophilic leukocytosis, arthritis, and an evanescent rash. There is often a delay in reaching a firm diagnosis. Differential diagnoses include infection, malignancy, and various immunologic disorders. Increased ferritin levels are of particular value in establishing the diagnosis. Clinical response to high-dose corticosteroids may be dramatic. We report a case of a 29-year-old woman who had recently been investigated for fever of unknown origin, and who presented to our hospital with high fever and hypotension. Her condition rapidly deteriorated with the development of ARDS, disseminated intravascular coagulation, and shock. The patient had a markedly elevated serum ferritin concentration of 26,000 ng/mL. High-dose pulse methylprednisolone therapy resulted in a remarkable clinical improvement. Such a severe case of systemic inflammatory response syndrome, masquerading as septic shock, has not been reported previously.

Carbon monoxide poisoning: a review for clinicians

Carbon monoxide (CO) poisoning continues to be a significant health problem both in the United States and in many other countries. CO poisoning is associated with a high incidence of severe morbidity and mortality. Epidemics of CO poisoning commonly occur during winter months and sources include: smoke from fires, fumes from heating systems burning fuels, and exhaust fumes from motor vehicles. The history of exposure and carboxyhemoglobin levels should alert the physician to this diagnosis. In the absence of exposure history, CO poisoning should be considered when two or more patients are simultaneously sick. The clinical presentation is non-specific and may range from nausea and headache to profound central nervous system dysfunction. The mainstay of therapy for CO poisoning is supplemental oxygen, ventilatory support, and monitoring for cardiac dysrhythmias. This article reviews up-to-date information of this potentially devastating exposure.

The role of anaerobes in patients with ventilator-associated pneumonia and aspiration pneumonia: a prospective study

CONTEXT

Aspiration of oropharyngeal material, with its high concentration of anaerobic bacteria, has been implicated in the pathogenesis of both ventilator-associated pneumonia (VAP) and aspiration pneumonitis (AP). Consequently, patients with these disorders are usually treated with antimicrobial agents with anaerobic activity.

OBJECTIVE

To determine the incidence of anaerobic bacteria in patients with VAP and AP.

DESIGN

Prospective, nonrandomized, interventional study.

SETTING

University-affiliated community teaching hospital.

PATIENTS AND INTERVENTIONS

We performed sequential blind protected specimen brush (PSB) sampling and mini-BAL in 143 patients with 185 episodes of suspected VAP and 25 patients with AP who required mechanical ventilation. Quantitative aerobic and anaerobic cultures were performed on all specimens. Pneumonia was considered to be present when either > 500 cfu/mL cultured from blind PSB sampling or > 5,000 cfu/mL cultured from mini-BAL were present.

RESULTS

Using the predefined criteria, bacterial pneumonia was diagnosed in 63 of 185 suspected VAP episodes (34%) and 12 of 25 patients with AP (48%). At least one dose of an antibiotic was given in the 24 h prior to bacteriologic sampling in 106 suspected VAP episodes (57%) and in 12 patients with AP (48%). More than one pathogen was isolated from 11 VAP and four AP patients. Pseudomonas aeruginosa, Staphylococcus aureus, and enteric Gram-negative organisms were isolated most frequently from patients with VAP. In the patients with AP, enteric Gram-negative organisms were isolated in patients with GI disorders and Streptococcus pneumoniae and Haemophilus influenzae predominated in patients with "community-acquired" aspiration. Only one anaerobic organism was isolated from the entire group of patients; Veillonella paravula was isolated from a blind PSB specimen in a patient with suspected aspiration pneumonia.

CONCLUSION

Despite painstaking effort, we were able to isolate only one anaerobic organism (nonpathogenic) from this group of patients. The spectrum of aerobes in patients with VAP was similar to that reported in the literature. The organisms found in patients with AP was a reflection of the organisms likely to colonize the oropharynx. The use of antibiotics with anaerobic coverage may not be necessary in patients with suspected VAP and AP. Furthermore, penicillin G and clindamycin may not be the antibiotics of choice in patients with AP.

The hemodynamic derangements in sepsis: implications for treatment strategies

The incidence of the sepsis syndrome has increased dramatically in the last few decades. During this time, we have gained new insights into the pathophysiologic mechanisms leading to organ dysfunction in this syndrome. Yet, despite this increased knowledge and the use of novel therapeutic approaches, the mortality associated with the sepsis syndrome has remained between 30% and 40%. Appropriate antibiotic selection and hemodynamic support remain the cornerstone of treatment of patients with sepsis. Recent studies have failed to demonstrate a global oxygen debt in patients with sepsis. Furthermore, therapy aimed at increasing systemic oxygen delivery has failed to consistently improve patient outcome. The primary aim of the initial phase of resuscitation is to restore an adequate tissue perfusion pressure. Aggressive volume resuscitation is considered the best initial therapy for the cardiovascular instability of sepsis. Vasoactive agents are required in patients who remain hemodynamically unstable or have evidence of tissue hypoxia after adequate volume resuscitation.

A case series of hospitalized patients with elevated digoxin levels

PURPOSE

Although there is renewed enthusiasm for the use of digoxin in patients with heart failure, current dosing guidelines are based on a nomogram published in 1974. We studied the incidence of and risk factors for elevated digoxin levels in patients admitted to a community hospital, and compared their dosage regimens to published guidelines.

SUBJECTS AND METHODS

We reviewed the charts of all patients who had serum digoxin levels greater than 2.4 ng/mL during a 6-month period. We collected demographic and clinical data, indications for digoxin use, digoxin dosage, concurrent medications, laboratory data, and clinical and electrocardiographic features of digoxin toxicity.

RESULTS

Of the 1,433 patients with digoxin assays, 115 (8%) patients had elevated levels. Of the 82 patients with complete records and correctly timed digoxin levels, 59 (72%) had electrocardiographic or clinical features of digoxin toxicity. Patients with serum digoxin levels >2.4 ng/mL were slightly older (78 +/- 8 versus 73 +/- 9 years of age; P = 0.12) and had greater serum creatinine levels (3.1 +/- 7.3 versus 1.4 +/- 0.3 mg/dL; P = 0.01) than those with levels < or =2.4 ng/mL. Forty-seven patients had elevated digoxin levels on admission, including 21 patients admitted for digoxin toxicity. Impaired or worsening renal function contributed to high levels in 37 patients, and a drug interaction was a contributory factor in 10 cases. Twenty (43%) of these patients were taking the recommended maintenance dose based on the scheme employed in the Digitalis Investigation Group study. Thirty-five patients developed high digoxin levels while in hospital. In 26 patients, this followed a loading dose of digoxin for the control of rapid atrial fibrillation. Impaired renal function was implicated in all of these patients. Despite the elevated digoxin level, rate control was achieved in only 11 patients of these patients.

CONCLUSIONS

Elevated digoxin levels and clinical toxicity remains a common adverse drug reaction. Elderly patients, particularly those with impaired renal function and low body weights, are at the greatest risk. As published digoxin nomograms often result in toxicity, clinical variables need to be monitored. In patients with congestive heart failure and normal sinus rhythm the potential benefit of digoxin is small; thus, patients should receive a dose that minimizes the risk of toxicity. For patients with new onset atrial fibrillation, other agents may be preferable for rate control.

A comparison of mini-bronchoalveolar lavage and blind-protected specimen brush sampling in ventilated patients with suspected pneumonia

PURPOSE

Mini-bronchoalveolar lavage (m-BAL) and blind-protected brush sampling (b-PSB) are minimally invasive methods of diagnosing pneumonia in mechanically ventilated patients. The aim of this study was to compare these techniques in a prospective study at a medical and surgical intensive care unit in a university-affiliated community teaching hospital.

PATIENTS AND METHODS

One hundred and ninety episodes of pneumonia was suspected in 175 mechanically ventilated patients. Sequential b-PSB followed by m-BAL were performed by respiratory therapists who had undergone specialized training. A b-PSB quantitative culture greater than 1,000 cfu/mL and a m-BAL greater than 10(4) cfu/mL was considered diagnostic of pneumonia. Colony counts between 500 and 1,000 cfu/mL and 5,000 - 10(4) cfu/mL, respectively, were considered borderline positive.

RESULTS

One hundred and ninety paired specimens were obtained from 175 patients. The diagnostic agreement between the two techniques was 90%. Sixty-six patients (37%) were considered to have bacterial pneumonia. In 108 episodes, patients were receiving concurrent antibiotics; pneumonia was diagnosed in 30 (27%) of these cases compared with 36 of 82 (43%) episodes off antibiotics (P = .03). In 6 episodes, m-BAL was negative and b-PSB was positive (1 patient receiving antibiotics). In 13 episodes, b-PSB was negative and m-BAL was positive (7 patients were receiving antibiotics). The b-PSB took 30 +/- 8 seconds to perform and was complicated by minor bleeding in 3 cases. The m-BAL took 5 +/- 2 minutes to perform, was considered easy in 105 cases, difficult/very difficult in 63, and failed in 2 patients. Significant coughing occurred in 98 patients with other minor reversible complications occurring in a further 20 cases.

CONCLUSIONS

In mechanically ventilated patients with suspected pneumonia both b-PSB and m-BAL can be performed safely by respiratory therapists. The tests complement each other and likely reduce the number of false-negative results.

Failure of once-daily vancomycin for staphylococcal endocarditis

With the emergence of staphylococci as important hospital pathogens, administration of vancomycin has increased dramatically. Economic and other factors have led to the development of once-daily dosing protocols to simplify and standardize the administration of antibiotics. A patient with Staphylococcus aureus prosthetic valve endocarditis and normal renal function failed therapy with vancomycin once/day. The infection was cured when the regimen was changed to the conventional 12-hour dosing interval.

Should a cancer patient be resuscitated following an in-hospital cardiac arrest?

OBJECTIVE

Previous reports from general hospitals and cancer centers have identified the presence of malignancy as a poor prognostic indicator for successful cardiopulmonary resuscitation (CPR) for an in-hospital cardiac arrest. The purpose of this study was to evaluate the initial success of CPR as determined by return of spontaneous circulation (ROSC), patient survival to hospital discharge, and 1-year survival of this group as compared to previous studies in non-oncological centers. In addition, the charges incurred in caring for these patients were analyzed.

MATERIALS AND METHODS

All cardiac arrests occurring between 1 January 1993 and 31 December 1994 were identified from a centralized morbidity and mortality database and reviewed retrospectively. Cardiac arrest was defined as the absence of a palpable pulse and initiation of CPR. Patients suffering pure respiratory arrest or shock without loss of pulse were excluded. Age, gender, primary site of malignancy, initial and ultimate outcome, including Zubrod's functional status (ZFS), and total hospital charges following cardiac arrest were recorded. Computerized billing records were used to tabulate total charges.

RESULTS

83 cardiac arrests occurred during the study period (42 women, 41 men). Mean age was 56.2 years. Forty-two percent of the patients had hematologic malignancies, 19% lung, 15% gastrointestinal, 5% head and neck cancers and 19% other malignancies. Sixty-six percent of the patients had ROSC. Only eight (9.6%) patients survived to hospital discharge: three died within 6 weeks under hospice care, two died within 6 months of discharge and only three (3.6%) patients survived to 1 year. Functional status follow-up of these three patients revealed two with ZFS 1 and one with ZFS 2. Total hospital charges for these 83 patients were US$ 2,959,740.

CONCLUSIONS

Although ROSC after cardiac arrest in our patients was better than that reported for most series in general hospitals, their ultimate survival and hospital discharge was extremely poor.

Cardiopulmonary resuscitation: a review for clinicians

Attempts at cardiopulmonary resuscitation (CPR) date from antiquity, but it is only in the last 50 years that a scientifically-based methodology has been developed. External chest compressions is the standard method for managing circulatory arrest, however, numerous alterations of this technique have been proposed in attempts to improve outcome from CPR. Defibrillation is the single most important therapy for the management of ventricular fibrillation or pulseless ventricular tachycardia. Adrenergic agents used to improve myocardial and cerebral perfusion are also the subject of considerable investigation with new agents entering clinical study. This paper reviews the history, current techniques and pharmacotherapy as well as controversial issues in the management of patients with cardiac arrest.