The effect of body mass index on patient outcomes in a medical ICU

STUDY OBJECTIVES: To examine the effect of patient body mass index (BMI) on outcome in intensive care. DESIGN: In a prospective study, the patients were classified into groups based on the calculated BMI, as follows: BMI < 19.0 (n = 350), > or = 19.0 and < 25.0 (n = 663), > or = 25.0 and < 29.9 (n = 585), > or = 30.0 and < 40.0 (n = 396), and > or = 40.0 (n = 154). Groups were compared by age, APACHE (acute physiology and chronic health evaluation) II score, mortality, ICU length of stay (LOS), hospital LOS, number receiving ventilation, and ventilator-days. Adverse events including nosocomial pneumonia, ventilator-days per patient, failed extubations, and line-related complications were recorded. SETTING: The study was conducted in a 9-bed medical ICU of a 650-bed tertiary care hospital. MEASUREMENTS: Height and weight were prospectively recorded for the first ICU admission during a hospital stay. RESULTS: Between January 1, 1997, and August 1, 2001, 2,148 of 2,806 patients admitted to the ICU had height and weight recorded. There were no differences in APACHE II score, mortality, ICU LOS, hospital LOS, number receiving ventilation, ventilator-days, average total cost, or average variable cost among the five groups. However, the severely obese patients were more frequently female and younger than those who were overweight and obese (p < 0.001). Adverse events were infrequent, but there were no differences between the obese/very obese compared with others. CONCLUSION: BMI has minimal effects on ICU outcome after patients are admitted to a critical care unit.     

Acute febrile respiratory illness in the ICU: reducing disease transmission

Acute febrile respiratory illness (FRI) leading to respiratory failure is a common reason for admission to the ICU. Viral pneumonia constitutes a portion of these cases, and often the viral etiology goes undiagnosed. Emerging viral infectious diseases such as severe acute respiratory syndrome and avian influenza present with acute FRIs progressing to respiratory failure and ARDS. Therefore, early recognition of a viral cause of acute FRI leading to ARDS becomes important for protection of health-care workers (HCWs), lessening spread to other patients, and notification of public health officials. These patients often have longer courses of viral shedding and undergo higher-risk procedures that may potentially generate aerosols, such as intubation, bronchoscopy, bag-valve mask ventilation, noninvasive positive pressure ventilation, and medication nebulization, further illustrating the importance of early detection and isolation. A small number of viral agents lead to acute FRI, respiratory failure, and ARDS: seasonal influenza, avian influenza, coronavirus associated with severe ARDS, respiratory syncytial virus, adenovirus, varicella, human metapneumovirus, and hantavirus. A systematic approach to early isolation, testing for these agents, and public health involvement becomes important in dealing with acute FRI. Ultimately, this approach will lead to improved HCW protection, reduction of transmission to other patients, and prevention of transmission in the community.     

Improving the ICU: part 1

ICUs are a vital component of modern health care. Improving ICU performance requires that we shift from a paradigm that concentrates on individual performance to a different paradigm that emphasizes the need to assess and improve ICU systems and processes. This is the first part of a two-part treatise. It discusses existing problems in ICU care, and the methods for defining and measuring ICU performance.     

Agreement between bedside blood and plasma glucose measurement in the ICU setting

STUDY OBJECTIVE: To assess the agreement between bedside glucose (bGlu) measurements and laboratory plasma glucose (pGlu) measurements in the ICU setting. DESIGN: Retrospective study. SETTING: ICU of a tertiary academic medical center. PATIENTS: One hundred ninety-seven patients admitted to the ICU from January through December 2002 who underwent 816 simultaneous bGlu and pGlu measurements. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: To calculate the agreement between the two methods of glucose measurement, the mean difference was obtained, and the limits of the agreement were calculated as the mean difference +/- 2 SDs. On 767 occasions, the mean bGlu was 159 mg/dL and the mean pGlu was 151 mg/dL (p < 0.001). The mean difference between the two techniques was 7.9 mg/dL (SD, 17.6 mg/dL), and the limits of agreement were + 43.1 and -27.2. On 31 occasions, the bGlu was reported as > 400 mg/dL, and in these cases the mean pGlu was 423 mg/dL (range, 300 to 900 mg/dL). On 18 occasions, the bGlu was reported as < 50 mg/dL, and in these cases the mean pGlu was 66.9 mg/dL (range, 13 to 198 mg/dL). CONCLUSIONS: On average, bGlu provides a reasonable estimate for pGlu. However, for the individual patient, bGlu gives an unreliable estimate for pGlu. All of those taking care of critically ill patients should be aware of the limitations of bedside glucometry.     

Thrombocytopenia in a surgical ICU.

STUDY OBJECTIVES: To assess the incidence of thrombocytopenia in surgical ICU patients, the factors associated with thrombocytopenia, the outcome of thrombocytopenic patients, and the possible mechanisms involved. DESIGN: Prospective study. SETTING: An 8-bed surgical ICU in an 885-bed teaching hospital. PATIENTS: 147 consecutive patients admitted to the surgical ICU during a 6-month period. MAIN OUTCOME MEASURES: Incidence of thrombocytopenia (defined by a platelet count < 100,000/mm3), risk factors for thrombocytopenia, or death in thrombocytopenic patients identified by a stepwise logistic regression analysis, as well as the mechanisms involved. RESULTS: Thrombocytopenia occurred in 52 patients (35%) with a mortality rate of 38%, compared with a 20% mortality rate in nonthrombocytopenic patients (p = 0.02). Sepsis, episodes of bleeding or transfusions, and an acute physiology and chronic health evaluation (APACHE) II score of > 15 were the independent risk factors identified for thrombocytopenia. The correction of thrombocytopenia was a protective factor reducing the risk of mortality in thrombocytopenic patients. Disseminated intravascular coagulation was found in 40% of thrombocytopenic patients, elevated platelet-associated IgG in 33%, and hemophagocytic histiocytes in 67%. Combinations of two of these mechanisms were demonstrated in one quarter of thrombocytopenic patients. CONCLUSIONS: Sepsis was the major independent risk factor identified. Thrombocytopenic patients had a higher ICU mortality due to the severity of overall clinical status. Bone marrow examination could be diagnostic when no obvious causes are demonstrated. Thrombocytopenia probably reflects the severity and course of an underlying pathologic condition, as its correction appears to be a good prognostic factor.     

Moderate sedation for chest physicians

Specialists in pulmonary and critical care medicine frequently perform invasive procedures that may require sedation or anesthesia for patient comfort. The number and complexities of interventional pulmonary procedures that can be performed in the bronchoscopy suite or critical care unit continues to expand. Procedures that formerly were done only in the operating room on inpatients are now done routinely in the office, ambulatory surgery center, or hospital outpatient department. No matter the setting, the key to successfully performing these procedures is a safe, pain-free environment for the patient. Anesthesia care and procedural sedation services share the goals of providing the patient comfort during a painful procedure and the operating physician an acceptable working environment. Historically, anesthesiologists have applied the expertise gained in managing anesthesia for major surgeries to sedation care for minor procedures. While the supply of anesthesiologists and anesthetists has shown only a modest increase, the growth in minimally invasive procedures has been explosive in recent years. To meet demand, a service, originally known as conscious sedation and now referred to as moderate sedation, has become common, in which the operating physician supervises a specially trained sedation nurse. This article will provide a clinical definition of moderate sedation and then focus on ways to properly code and bill for pulmonary procedures performed with moderate sedation.     

Clinical characteristics and outcomes of obstetric patients requiring ICU admission

OBJECTIVES: To review a series of critically ill obstetric patients admitted to our ICU to assess the spectrum of disease, required interventions, and fetal/maternal mortality, and to identify conditions associated with maternal death. DESIGN: Retrospective cohort. SETTING: Medical-surgical ICU in a university-affiliated hospital. PATIENTS: Pregnant/postpartum admissions between January 1, 1998, and September 30, 2005. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: We studied 161 patients (age, 28 +/- 9 years; mean gestational age, 29 +/- 9 weeks) [mean +/- SD], constituting 10% of 1,571 hospital admissions. APACHE (acute physiology and chronic health evaluation) II score was 14 +/- 8, with 24% predicted mortality; sequential organ failure assessment score was 5 +/- 3; and therapeutic intervention scoring system at 24 h was 25 +/- 9. Forty-one percent of patients required mechanical ventilation (MV). ARDS, shock, and organ dysfunction were present in 19%, 25%, and 48% of patients, respectively. Most patients (63%) were admitted postpartum, and 74% of admissions were of obstetric cause. Hypertensive disease (40%), major hemorrhage (16%), septic abortion (12%), and nonobstetric sepsis (10%) were the principal diagnoses. Maternal mortality was 11%, with multiple organ dysfunction syndrome (44%) and intracranial hemorrhage (39%) as main causes. There were no differences in death rate in patients admitted for obstetric and nonobstetric causes. Fetal mortality was 32%. Only 30% of patients received antenatal care, which was more frequent in survivors (33% vs 6% nonsurvivors, p = 0.014). CONCLUSIONS: Although ARDS, organ failures, shock, and use of MV were extremely frequent in this population, maternal mortality remains within an acceptable range. APACHE II overpredicted mortality in these patients. Septic abortion is still an important modifiable cause of mortality. Efforts should concentrate in increasing antenatal care, which was clearly underprovided in these patients.     

Outcome of patients with small-vessel vasculitis admitted to a medical ICU

PURPOSES: This study aims to describe the clinical course and prognostic factors of patients with small-vessel vasculitis admitted to a medical ICU. METHODS: We reviewed the clinical records of 38 patients with small-vessel vasculitis admitted consecutively to the ICU between January 1997 and May 2004. The APACHE (acute physiology and chronic health evaluation) III prognostic system was used to determine the severity of illness on the first ICU day; the sequential organ failure assessment (SOFA) score was used to measure organ dysfunction, and the Birmingham vasculitis activity score for Wegener granulomatosis (BVAS/WG) was used to assess vasculitis activity. Outcome measures were the 28-day mortality and ICU length of stay. RESULTS: Nineteen patients (50%) had Wegener granulomatosis, 16 patients (42%) had microscopic polyangiitis, 2 patients had CNS vasculitis, and 1 patient had Churg-Strauss syndrome. Reasons for ICU admission included alveolar hemorrhage in 14 patients (37%), sepsis in 5 patients (13%), seizures in 3 patients (8%), and pneumonia in 2 patients (5%). The median ICU length of stay was 4.0 days (interquartile range, 2.0 to 6.0 days). The APACHE III score was lower in survivors than nonsurvivors (p = 0.010). The predicted hospital mortality was 54% for nonsurvivors and 21% for survivors (p = 0.0038). The mean SOFA score was 11.6 (SD, 2.6) in nonsurvivors, compared to 6.9 (SD, 2.4) in survivors (p = 0.0004). Mean BVAS/WG scores were 8.6 (SD, 3.6) in nonsurvivors and 4.7 (SD, 4.6) in survivors (p = 0.0889). Twenty-six percent of the patients received invasive mechanical ventilation, and 33% underwent dialysis. The 28-day and 1-year mortality rates were 11% and 29%, respectively. CONCLUSIONS: The mortality of patients with small-vessel vasculitis admitted to the ICU is lower than predicted, and alveolar hemorrhage is the most common reason for ICU admission.     

Improving the ICU: part 2

ICUs are a vital but troubled component of modern health-care systems. Improving ICU performance requires that we shift from a paradigm that concentrates on individual performance, to a systems-oriented approach that emphasizes the need to assess and improve the ICU systems and processes that hinder the ability of individuals to perform their jobs well. This second part of a two-part treatise establishes a practical framework for performance improvement and examines specific strategies to improve ICU performance, including the use of information systems.