Eosinopenia is a reliable marker of sepsis on admission to medical intensive care units

Introduction

Eosinopenia is a cheap and forgotten marker of acute infection that has not been evaluated previously in intensive care units (ICUs). The aim of the present study was to test the value of eosinopenia in the diagnosis of sepsis in patients admitted to ICUs.

Methods

A prospective study of consecutive adult patients admitted to a 12-bed medical ICU was performed. Eosinophils were measured at ICU admission. Two intensivists blinded to the eosinophils classified patients as negative or with systemic inflammatory response syndrome (SIRS), sepsis, severe sepsis, or septic shock.

Results

A total of 177 patients were enrolled. In discriminating noninfected (negative + SIRS) and infected (sepsis + severe sepsis + septic shock) groups, the area under the receiver operating characteristic curve was 0.89 (95% confidence interval (CI), 0.83 to 0.94). Eosinophils at <50 cells/mm³ yielded a sensitivity of 80% (95% CI, 71% to 86%), a specificity of 91% (95% CI, 79% to 96%), a positive likelihood ratio of 9.12 (95% CI, 3.9 to 21), and a negative likelihood ratio of 0.21(95% CI, 0.15 to 0.31). In discriminating SIRS and infected groups, the area under the receiver operating characteristic curve was 0.84 (95% CI, 0.74 to 0.94). Eosinophils at <40 cells/mm³ yielded a sensitivity of 80% (95% CI, 71% to 86%), a specificity of 80% (95% CI, 55% to 93%), a positive likelihood ratio of 4 (95% CI, 1.65 to 9.65), and a negative likelihood ratio of 0.25 (95% CI, 0.17 to 0.36).

Conclusion

Eosinopenia is a good diagnostic marker in distinguishing between noninfection and infection, but is a moderate marker in discriminating between SIRS and infection in newly admitted critically ill patients. Eosinopenia may become a helpful clinical tool in ICU practices.     

Treatment of sepsis in an intensive care unit

The management of severe bacterial sepsis is an integral part of intensive care medicine. Early and appropriate treatment with antimicrobials positively affects mortality and significantly reduces the time spent in both intensive care and the hospital. Drug choice is usually made on a “best guess” basis and instituted prior to receipt of appropriate blood, sputum, urine or drainage culture results. Bactericidal drugs should be given in combination, delivered by intravenous bolus and directed towards broad cover of all likely pathogens. Aminoglycoside/ureidopenicillin combinations are synergistic and widely used — often combined with metronidazole. Aminoglycoside toxicity can be reduced by giving the drug once daily (OD) rather than by traditional multiple daily dosing (MDD) and by measuring peak and trough serum levels. Efficacy is increased by attention to the peak serum level/MIC ratio which determines the response to treatment. Several newer agents have been more recently introduced. These drugs include ceftazidime, imipenem/cilastatin, the quinolones and clavulanic acid/semisynthetic penicillin combinations. Other newer drugs currently under evaluation include aztreonam, teicoplanin, the penems and carbapenems.     

Treatment of sepsis in an intensive care unit

The management of severe bacterial sepsis is an integral part of intensive care medicine. Early and appropriate treatment with antimicrobials positively affects mortality and significantly reduces the time spent in both intensive care and the hospital. Drug choice is usually made on a best guess basis and instituted prior to receipt of appropriate blood, sputum, urine or drainage culture results. Bactericidal drugs should be given in combination, delivered by intravenous bolus and directed towards broad cover of all likely pathogens. Aminoglycoside/ureidopenicillin combinations are synergistic and widely used — often combined with metronidazole. Aminoglycoside toxicity can be reduced by giving the drug once daily (OD) rather than by traditional multiple daily dosing (MDD) and by measuring peak and trough serum levels. Efficacy is increased by attention to the peak serum level/MIC ratio which determines the response to treatment. Several newer agents have been more recently introduced. These drugs include ceftazidime, imipenem/cilastatin, the quinolones and clavulanic acid/semisynthetic penicillin combinations. Other newer drugs currently under evaluation include aztreonam, teicoplanin, the penems and carbapenems.     

Nosocomial sepsis in the neonatal intensive care unit

During a 12-month study of the causes of and risk factors for nosocomial sepsis in a neonatal intensive care unit (NICU), we detected 23 episodes of nosocomial sepsis in 20 of the 155 infants at risk who were hospitalized in the NICU for at least one week. The associated mortality was 20%. Gram-positive organisms accounted for 15 (65%) of the episodes. Low birth weight, multiple gestation, and prolonged hospitalization were significant risk factors for nosocomial sepsis by univariate analysis; together, these three factors correctly predicted 80% of the infants with sepsis and 82% of the control subjects. By logistic regression analysis, however, length of stay was not a significant risk factor, but rather a confounding variable that was highly associated with birth weight. Analysis of risk factors for nosocomial sepsis showed that previous antibiotic therapy placed an infant at risk for candidemia; assisted ventilation was a risk factor for sepsis caused by group D Streptococcus and Candida albicans. Sepsis was related to infected or malfunctioning intravascular catheters in nine of the 20 infants with sepsis. Further investigation to determine strategies for preventing nosocomial septicemia in the low birth weight infant is warranted.     

Impact of hemodynamic monitoring in a medical intensive care unit

Previous reports have shown hemodynamic data inaccurately predicted by physical examination and x-ray findings. Although invasive hemodynamic monitoring has been shown to significantly alter the management of critically ill patients, the impact on mortality has been difficult to assess. In a prospective study of 35 patients, we found inaccurate predictions of left and right heart filling pressures by clinical assessment. However, cardiac output was accurately estimated. Management was altered 34% of the time because of invasive hemodynamic assessment; however, mortality was not affected by a change in therapy.     

Prospective evaluation of self-extubations in a medical intensive care unit

Objective To evaluate the incidence, associated factors and gravity of self-extubations.Design Prospective study about all patients intubated over an 8 month period.Setting A medical intensive care unit of a University Hospital.Patients Patients were divided into two groups: self-extubated and those that did not. The self-extubations were separated into deliberate acts by the patients and accidental.Results 24 of the 197 patients included presented a total of 27 extubations (12%). There were 21 deliberate incidents and 6 accidental. The only differences between the cases and the rest of the population were a higher mean age (67 vs 59 years) and a larger proportion of chronic respiratory failure (66% versus 35%). Reintubation was necessary in 20 cases (74%) within 30 min in 16 cases. The main indication for reintubation was acute respiratory distress (90%). Reintubation was associated with one death.Conclusion Self-extubation is a frequent and serious complication of mechanical ventilation. Deliberate self-extubation, the most frequent type of incident could possibly be reduced by better sedation of agitated patients and accidental self-extubation by better training of the nursing staff.     

Acute abdomen in the medical intensive care unit

OBJECTIVE: Acute abdominal complication in the medical intensive care unit may be underdiagnosed and can add significant risk of death. We hypothesize that delays in surgery because of atypical presentation, such as the absence of peritoneal signs, may contribute to mortality. DESIGN: Retrospective cohort study (1995-2000). SETTING: Medical intensive care unit in a tertiary care center. PATIENTS: Medical intensive care unit patients with clinical, surgical, or autopsy diagnosis of acute abdominal catastrophe (gangrenous or perforated viscus). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Seventy-seven patients (1.3%) met inclusion criteria. Ischemic bowel was the most common diagnosis, followed by perforated ulcer, bowel obstruction, and cholecystitis. Actual mortality rate was higher than predicted by Acute Physiology and Chronic Health Evaluation (APACHE) III scores at the time of medical intensive care unit admission (63% vs. 31%). Twenty-six patients (34%) did not have surgery, and none of these survived. Fifty-one patients underwent surgery and 28 survived (56%). Delay in surgical evaluation (p <.01) and intervention (p <.03), APACHE III scores (p <.01), renal insufficiency (p <.01), and a diagnosis of ischemic bowel (p <.01) were associated with increased mortality rates. Surgical delay was more likely to occur in patients with altered mental state (p <.01), no peritoneal signs (p <.01), previous opioids (p <.03), antibiotics (p <.02), and mechanical ventilation (p <.02). CONCLUSION: Delays in surgical evaluation and intervention are critical contributors to mortality rate in patients who develop acute abdominal complications in a medical intensive care unit.     

Usefulness of intra-abdominal pressure in a predominantly medical intensive care unit

Background

The deleterious effects of elevated intra-abdominal pressure (IAP) have been known for more than a century. The proposed objectives were to measure changes in IAP and analyze increase-related factors and complications and whether high IAP and its persistence are related to complications and mortality in a predominantly medical intensive care unit.

Methods

Over a 1-year period, we conducted a prospective cohort study in which IAP was measured using the bladder method. Hospitalization time, demographic variables, diagnosis on admission, APACHE II score, and clinical complications were recorded.

Results

A total of 130 patients were studied. Overall mean IAP was 12.3 mm Hg (standard deviation [SD], 3.79; 95% confidence interval [CI], 11.7-13), and on the first day, 12.68 mm Hg (SD, 5.32; 95% CI, 11.8-13.6); maximum IAP was 16.4 mm Hg (SD, 4.6; 95% CI, 15.6-17.2). A positive correlation was found between IAP, APACHE (Acute Physiology And Chronic Health Evaluation) II, and age. Higher IAP values were independently associated with higher age, prolonged activated partial thromboplastin time, need for dialysis, and intolerance to enteral feeding. The value showing the best sensitivity and specificity in predicting mortality was persistence of IAP 20 mm Hg or greater for 4 days or more. The number of days with IAP 20 mm Hg or greater was a factor associated with a higher risk of death (odds ratio, 2.3). Patients who died showed a tendency to increased IAP.

Conclusion

In this study, a threshold IAP of 20 mm Hg and its permanence over time were the best predictive factors of complications and mortality. Among other relationships, we also observed that older patients had higher IAP. High IAP was a cause of intolerance to enteral nutrition.     

Visiting preferences of patients in the intensive care unit and in a complex care medical unit.

BACKGROUND: Within the challenging healthcare environment are nurses, patients, and patients' families. Families want proximity to their loved ones, but the benefits of such proximity depend on patients' conditions and family-patient dynamics. OBJECTIVES: To describe patients' preferences for family visiting in an intensive care unit and a complex care medical unit. METHODS: Sixty-two patients participated in a structured interview that assessed patients' preferences for visiting, stressors and benefits of visiting, and patients' perceived satisfaction with hospital guidelines for visiting. RESULTS: Patients in both units rated visiting as a nonstressful experience because visitors offered moderate levels of reassurance, comfort, and calming. Patients in the intensive care unit worried more about their families than did patients in the complex care medical unit but valued the fact that visitors could interpret information for the patients while providing information to assist the nurse in understanding the patients. Patients in the intensive care unit were more satisfied with visiting practices than were patients in the complex care medical unit, although both groups preferred visits of 35 to 55 minutes, 3 to 4 times a day, and with usually no more than 3 visitors. CONCLUSIONS: These data provide the input of patients in the ongoing discussion of visiting practices in both intensive care units and complex care medical units. Patients were very satisfied with a visiting guideline that is flexible enough to meet their needs and those of their family members.     

Nursing home patients admitted to a medical intensive care unit

To investigate admissions from nursing homes to a medical intensive care unit (ICU), the authors detailed the major interventions, costs, and outcomes for such patients (n = 67) over a 3-year period and then compared them with those for ICU patients receiving home care or visiting nurse services (240 patients) before admission and all others older than 65 years of age (949 patients). These three groups comprised 37% of total ICU admissions. In contrast to younger patients admitted primarily with acute ischemic heart disease, nursing home patients were more likely to be admitted with cardiopulmonary arrest, infection, and gastrointestinal bleeding. Major interventions of intubation and mechanical ventilation were most frequent for nursing home patients, but total hospital charges differed little among the groups. In-hospital mortality for the nursing home group (28%) was significantly higher than for the home care group (7%) and others older than 65 years of age (7%). Cumulative mortality for the nursing home group reached 66% by 8 months, versus 32% and 26% in the other groups, respectively.     

Age, chronic disease, sepsis, organ system failure, and mortality in a medical intensive care unit

We retrospectively studied relations between age, pre-existing chronic disease, sepsis, organ system failure, and mortality in 487 patients from a medical ICU. Single organ system failure (SOSF) occurred in 136 (28%) and multiple (greater than or equal to 2) organ system failure (MOSF) in 187 (38%) patients. Cardiovascular and pulmonary failure predominated. Overall mortality was 27%. SOSF mortality was 16% and for MOSF 58%. Eighty-three percent of nonsurvivors had MOSF. Hence, MOSF is common and a major cause of death in critically ill medical patients. Advancing age and prior chronic disease may diminish physiologic reserve and predispose to sepsis and MOSF. Although sepsis is a major risk factor for MOSF, a nonspecific host response to critical illness may contribute to the syndrome in 35% of patients. Advancing age, chronic disease, and the number of failing organs, particularly failure of cardiovascular, pulmonary, renal, and neurologic systems, are major determinants of overall mortality, but sepsis is not an independent contributor.     

Electronic medical record in the intensive care unit.

The EMR in the ICU has the utility of providing the necessary information to make sound clinical decisions for critically ill patients. For it to be optimized, the EMR must be more than just what is being replicated in the written record or merely a documentation tool; it must add value that supports and enhances clinical decision support. The EMR is too expensive a tool just to be a computer designed to ease documentation and retrieve data faster. Gardner and Huff have suggested that the EMR must answer three questions: Why, What, and So What. The "Why" is relatively easy to answer, but the "What" data to use so that the information is meaningful to a provider and the "So What" are more difficult to answer. Provided one can qualitatively assess "What" information is important for a health care provider, then "So What" becomes an important objective in the empirical quantification of the benefits that the EMR provides. It is clear that to analyze some of the outcomes that health care delivery provides, one needs some mechanism to automate the information at the point of care, particularly now that the regulatory agencies are requiring it. Given the fact that there is no single integrated computerized patient record, this becomes the daunting task for the next century. Making it easier for health care providers to interact with the system and providing them with instantaneous feedback that changes their medical decision so they can deliver better care (clinical pathways, clinical practice guidelines) will be the task required of the next generation of CISs.     

Evaluation of an intensive insulin protocol for septic patients in a medical intensive care unit

OBJECTIVE: Intensive insulin therapy to normalize blood glucose may improve outcome in intensive care unit patients. We prospectively evaluated the implementation of an intensive insulin protocol in medical intensive care patients to identify and overcome obstacles that this complex therapy creates. DESIGN: This prospective, quality assessment study was designed to establish a standard protocol for glucose control in critically ill patients. SETTING: The study took place in the medical intensive care unit at the Medical University of South Carolina, a tertiary care center. PATIENTS: Patients diagnosed with sepsis and two consecutive blood glucose measurements of >120 mg/dL were included in the study. INTERVENTIONS: The protocol, targeting blood glucose of 80-120 mg/dL, was a multidisciplinary initiative involving extensive education of house staff before subject enrollment. Based on predefined criteria, patients were monitored daily for glycemic control, inclusion criteria, and protocol adherence. Protocol improvements were assessed at 6 and 12 months via nursing surveys. MEASUREMENTS AND MAIN RESULTS: Seventy patients receiving insulin infusion for >8 hrs were included in data analysis, accounting for 4,920 glucose readings. Eighty-six hypoglycemic events were recorded, with the number of events decreasing from 7.6% to 0.3% by the final version of the protocol. Average duration on protocol was 6 days, and average time to target range was 5.4 hrs. Identifiable causes of hypoglycemia and survey results led to four protocol revisions by study completion. CONCLUSIONS: In comparison to studies suggesting that normoglycemia is an easily achievable goal, our protocol often recorded glucose values <80 mg/dL, although values <60 mg/dL were rare and usually due to protocol violations. In the interval before automated glucose-sensing insulin infusion devices become available for the intensive care unit, the current protocol is available to assist others in achieving target glucose levels shown to improve mortality rate in an intensive care unit population.     

重症监护室常用血糖测量方法的一致性研究

目的 评价目前重症监护室(intensive care unit,ICU)常用的4种血糖测量方法与静脉血/血生化仪法的一致性,并分析可能的影响因素.方法 前瞻性序贯纳入2007年11月至2008年1月期间收入北京协和医院内科ICU病房且预期ICU住院时间＞48 h的患者49例,共检测血糖130组,每组均采用毛细血管血/血糖仪法、动脉血/血糖仪法、动脉血/血气分析仪法和动脉血/血生化仪法测量血糖,分别计算上述4种方法与静脉血/血生化仪法(标准法)所测血糖值的差值、相关系数、偏倚校正因子及不一致率,并采用Logistic回归分析影响一致性的因素.结果 毛细血管血/血糖仪法、动脉血/血糖仪法、动脉血/血气分析仪法、动脉血/血生化仪法所测血糖值与标准法所测血糖值的差值分别为:(1.7±1.4)mmol/L,(1.6±1.4)mmol/L,(1.1±1.2)mmol/L,(0.5±1.2)mmol/L,不一致率分别为66.9%,63.8%,40.0%,23.8%.相关系数分别为0.844,0.845,0.895和0.896,偏倚校正因子分别为0.821,0.831,0.914和0.979.红细胞比积减低是毛细血管血/血糖仪法(OR=0.923,P=0.03)和动脉血/血糖仪法(OR=0.921,P=0.014)血糖测量值与标准法不一致的独立危险因素.结论 在重症监护病房,采用血糖仪测量血糖的方法与标准法的一致性均较差,而血气分析仪法则是一致性较好的床旁血糖检测方法.红细胞比积减低可影响血糖仪测量的准确性.

Abstract：

Objective To evaluate the accuracy of five blood glucose measurements commonly used in ICU and to determine the potential factors interfering the accuracy. Method This prospective study carried out in consecutively enrolled 49 patients stayed more than 48 hours in the medical ICU of Peking Union Medical College Hospital from November 2007 to January 2008. A total of 130 blood samples were measured to determine blood glucose with five different methods, and the biochemistry analyzer in central laboratory was regarded as reference method for comparison with other four methods, ( 1 ) capillary blood/glucometer;(2) arterial blood/glucometer; (3) arterial blood/blood gas analyzer; and (4) arterial blood/biochemistry analyzer. The accuracy of a method tested was judged by the difference in level of blood glucose between it and reference method, correlation coefficient, bias correction factor and discrepancy. The independent factors for the discrepancies were identified by multivariate logistic regression. Results The values of differences in level of blood glucose between above four methods and the reference were ( 1.7 ± 1.4) mmol/L,( 1.6 ± 1.4 ) mmol/L, ( 1.1 ± 1.2) mmol/L, and (0.5 ± 1.2 ) mmol/L, respectively. The rates of discrepancy were 66.9%, 63.8%, 40.0% and 23.8%. The correlation coefficients were 0. 844, 0. 845, 0. 895and 0. 896. The bias correction factors were 0. 821,0.831,0.914 and 0. 979. Decrease in hematocrit was statistically associated with the discrepancy between glucometer analysis methods and the reference, with OR of 0.923 for capillary blood ( P = 0.03 ) and 0. 912 for arterial blood( P = 0.014), respectively. Conclusions Glucometer analysis poorly correlated with reference method and blood gas analysis in ICU patients. Decrease in hematocrit significantly increased the degree of discrepancy in glucose measurements between glucometer analysis and the reference.     

重症监护室常用血糖测量方法的一致性研究

Objective To evaluate the accuracy of five blood glucose measurements commonly used in ICU and to determine the potential factors interfering the accuracy. Method This prospective study carried out in consecutively enrolled 49 patients stayed more than 48 hours in the medical ICU of Peking Union Medical College Hospital from November 2007 to January 2008. A total of 130 blood samples were measured to determine blood glucose with five different methods, and the biochemistry analyzer in central laboratory was regarded as reference method for comparison with other four methods, ( 1 ) capillary blood/glucometer;(2) arterial blood/glucometer; (3) arterial blood/blood gas analyzer; and (4) arterial blood/biochemistry analyzer. The accuracy of a method tested was judged by the difference in level of blood glucose between it and reference method, correlation coefficient, bias correction factor and discrepancy. The independent factors for the discrepancies were identified by multivariate logistic regression. Results The values of differences in level of blood glucose between above four methods and the reference were ( 1.7 ± 1.4) mmol/L,( 1.6 ± 1.4 ) mmol/L, ( 1.1 ± 1.2) mmol/L, and (0.5 ± 1.2 ) mmol/L, respectively. The rates of discrepancy were 66.9%, 63.8%, 40.0% and 23.8%. The correlation coefficients were 0. 844, 0. 845, 0. 895and 0. 896. The bias correction factors were 0. 821,0.831,0.914 and 0. 979. Decrease in hematocrit was statistically associated with the discrepancy between glucometer analysis methods and the reference, with OR of 0.923 for capillary blood ( P = 0.03 ) and 0. 912 for arterial blood( P = 0.014), respectively. Conclusions Glucometer analysis poorly correlated with reference method and blood gas analysis in ICU patients. Decrease in hematocrit significantly increased the degree of discrepancy in glucose measurements between glucometer analysis and the reference.