Role of organisational factors on the 'weekend effect' in critically ill patients in Brazil: a retrospective cohort analysis

INTRODUCTION

Higher mortality for patients admitted to intensive care units (ICUs) during the weekends has been occasionally reported with conflicting results that could be related to organisational factors. We investigated the effects of ICU organisational and staffing patterns on the potential association between weekend admission and outcomes in critically ill patients.

METHODS

We included 59 614 patients admitted to 78 ICUs participating during 2013. We defined 'weekend admission' as any ICU admission from Friday 19:00 until Monday 07:00. We assessed the association between weekend admission with hospital mortality using a mixed logistic regression model controlling for both patient-level (illness severity, age, comorbidities, performance status and admission type) and ICU-level (decrease in nurse/bed ratio on weekend, full-time intensivist coverage, use of checklists on weekends and number of institutional protocols) confounders. We performed secondary analyses in the subgroup of scheduled surgical admissions.

RESULTS

A total of 41 894 patients (70.3%) were admitted on weekdays and 17 720 patients (29.7%) on weekends. In univariable analysis, weekend admitted patients had higher ICU (10.9% vs 9.0%, P<0.001) and hospital (16.5% vs 13.5%, P<0.001) mortality. After adjusting for confounders, weekend admission was not associated with higher hospital mortality (OR 1.05, 95% CI 0.99 to 1.12, P=0.095). However, a 'weekend effect' was still observed in scheduled surgical admissions, as well as in ICUs not using checklists during the weekends. For unscheduled admissions, no 'weekend effect' was observed regardless of ICU's characteristics. For scheduled surgical admissions, a 'weekend effect' was present only in ICUs with a low number of implemented protocols and those with a reduction in the nurse/bed ratio and not applying checklists during weekends.

CONCLUSIONS

ICU organisational factors, such as decreased nurse-to-patient ratio, absence of checklists and fewer standardised protocols, may explain, in part, increases in mortality in patients admitted to the ICU mortality on weekends.

A gradient-boosted model analysis of the impact of body mass index on the short-term outcomes of critically ill medical patients

Objective

To evaluate the impact of body mass index on the short-term prognosis of non-surgical critically ill patients while controlling for performance status and comorbidities.

Methods

We performed a retrospective analysis on a two-year single-center database including 1943 patients. We evaluated the impact of body mass index on hospital mortality using a gradient-boosted model that also included comorbidities and was assessed by Charlson’s comorbidity index, performance status and illness severity, which was measured by the SAPS3 score. The SAPS3 score was adjusted to avoid including the same variable twice in the model. We also assessed the impact of body mass index on the length of stay in the hospital after intensive care unit admission using multiple linear regressions.

Results

A low value (< 20kg/m²) was associated with a sharp increase in hospital mortality. Mortality tended to subsequently decrease as body mass index increased, but the impact of a high body mass index in defining mortality was low. Mortality increased as the burden of comorbidities increased and as the performance status decreased. Body mass index interacted with the impact of SAPS3 on patient outcome, but there was no significant interaction between body mass index, performance status and comorbidities. There was no apparent association between body mass index and the length of stay at the hospital after intensive care unit admission.

Conclusion

Body mass index does appear to influence the shortterm outcomes of critically ill medical patients, who are generally underweight. This association was independent of comorbidities and performance status.

Organizational characteristics, outcomes, and resource use in 78 Brazilian intensive care units: the ORCHESTRA study

PURPOSE

Detailed information on organization and process of care in intensive care units (ICU) in emerging countries is scarce. Here, we investigated the impact of organizational factors on the outcomes and resource use in a large sample of Brazilian ICUs.

METHODS

Retrospective cohort study of 59,693 patients (medical admissions, 67 %) admitted to 78 ICUs during 2013. We retrieved patients' data from an ICU quality registry and surveyed ICUs regarding structure, organization, staffing patterns, and process of care. We used multilevel logistic regression analysis to identify factors associated with hospital mortality. Efficient resource use was assessed by estimating standardized resource use and mortality rates adjusted for the SAPS 3 score.

RESULTS

ICUs were mostly medical-surgical (79 %) and located at private hospitals (86 %). Median nurse to bed ratio was 0.20 (IQR, 0.15-0.28) and board-certified intensivists were present 24/7 in 16 (21 %) of ICUs. Multidisciplinary rounds occurred in 67 (86 %) and daily checklists were used in 36 (46 %) ICUs. Most frequent protocols focused on sepsis management and prevention of healthcare-associated infections. Hospital mortality was 14.4 %. In multivariable analysis, the number of protocols was the only organizational characteristic associated with mortality [odds ratio = 0.944 (95 % CI 0.904-0.987)]. The effects of protocols were consistent across subgroups including surgical and medical patients as well as the SAPS 3 tertiles. We also observed a significant trend toward efficient resource use as the number of protocols increased.

CONCLUSIONS

In emerging countries such as Brazil, organizational factors, including the implementation of protocols, are potential targets to improve patient outcomes and resource use in ICUs.

Effects of Organizational Characteristics on Outcomes and Resource Use in Patients With Cancer Admitted to Intensive Care Units

PURPOSE

To investigate the impact of organizational characteristics and processes of care on hospital mortality and resource use in patients with cancer admitted to intensive care units (ICUs).

PATIENTS AND METHODS

We performed a retrospective cohort study of 9,946 patients with cancer (solid, n = 8,956; hematologic, n = 990) admitted to 70 ICUs (51 located in general hospitals and 19 in cancer centers) during 2013. We retrieved patients' clinical and outcome data from an electronic ICU quality registry. We surveyed ICUs regarding structure, organization, staffing patterns, and processes of care. We used mixed multivariable logistic regression analysis to identify characteristics associated with hospital mortality and efficient resource use in the ICU.

RESULTS

Median number of patients with cancer per center was 110 (interquartile range, 58 to 154), corresponding to 17.9% of all ICU admissions. ICU and hospital mortality rates were 15.9% and 25.4%, respectively. After adjusting for relevant patient characteristics, presence of clinical pharmacists in the ICU (odds ratio [OR], 0.67; 95% CI, 0.49 to 0.90), number of protocols (OR, 0.92; 95% CI, 0.87 to 0.98), and daily meetings between oncologists and intensivists for care planning (OR, 0.69; 95% CI, 0.52 to 0.91) were associated with lower mortality. Implementation of protocols (OR, 1.52; 95% CI, 1.11 to 2.07) and meetings between oncologists and intensivists (OR, 4.70; 95% CI, 1.15 to 19.22) were also independently associated with more efficient resource use. Neither admission to ICUs in cancer centers compared with general hospitals nor annual case volume had an impact on mortality or resource use.

CONCLUSION

Organizational aspects, namely the implementation of protocols and presence of clinical pharmacists in the ICU, and close collaboration between oncologists and ICU teams are targets to improve mortality and resource use in critically ill patients with cancer.

Georeferencing of deaths from sepsis in the city of São Paulo

Objective

The aim of the present study was to obtain information about deaths due to sepsis in São Paulo from 2004 to 2009 and their relationship with geographical distribution.

Methods

Causes of death, both main and secondary, were defined according to the codes of the International Classification of Disease version 10 (ICD-10) contained in the database. Sepsis, septic shock, multiple organ failure, pneumonia, urinary tract infection, peritonitis and other intraabdominal infections, skin and soft tissue infections (including surgical wound infection) and meningitis were considered as immediate cause of death or as the condition leading to the immediate cause of death related or associated to sepsis.

Results

In the analyzed period, there was a 15.3% increase in the absolute number of deaths from sepsis in São Paulo. The mean number of deaths during this period was 28,472 ± 1566. Most deaths due to sepsis and sepsis-related diseases over the studied period occurred in a hospital or health care facility, showing that most of the patients received medical care during the event that led to death. We observed a significant concentration of deaths in the most populous regions, tending more toward the center of the city.

Conclusions

Georeferencing data from death certificates or other sources can be a powerful tool to uncover regional epidemiological differences between populations. Our study revealed an even distribution of sepsis all over the inhabited areas of São Paulo.

The impact of performance status and comorbidities on the short-term prognosis of very elderly patients admitted to the ICU

BACKGROUND

Patients ≥80 years of age are increasingly being admitted to the intensive care unit (ICU). The impact of relevant variables, such comorbidities and performance status, on short-term outcomes in the very elderly is largely unknown. Few studies address the calibration of illness severity scores (SAPS3 score) within this population. We investigated the risk factors for hospital mortality in critically ill patients ≥80 years old, emphasizing performance status and comorbidities, and assessed the calibration of SAPS3 scores in this population.

METHODS

1129 very elderly patients admitted to a tertiary ICU in Brazil during a two-year period were retrospectively included in this study. Demographic features, reasons for admission, illness severity, comorbidities (including the Charlson Comorbidity Index) and a simplified performance status measurement were obtained. After univariate analysis, a multivariate model was created to evaluate the factors that were associated with hospital mortality. Alternatively, a conditional inference tree with recursive partitioning was constructed. Calibration of the SAPS3 scores and the multivariate model were evaluated using the Hosmer-Lemeshow test and a calibration plot. Discrimination was assessed using a receiver operating characteristics curve.

RESULTS

On multivariate analysis after stepwise regression, only the SAPS3 score (OR 1.08, 95% CI 1.06-1.10), Charlson Index (OR 1.16, 95% CI 1.07-1.27), performance status (OR 1.61, 95% CI 1.05-2.64 for partially dependent patients and OR 2.39, 95% CI 1.38-4.13 for fully dependent patients) and a non-full code status (OR 11.74, 95% CI 6.22-22.160) were associated with increased hospital mortality. Conditional inference tree showed that performance status and Charlson Index had the greatest influence on patients with less severe disease, whereas a non-full code status was prominent in patients with higher illness severity (SAPS3 score >61). The model obtained after logistic regression that included the before mentioned variables demonstrated better calibration and greater discrimination capability (AUC 0.86, 95% CI 0.83-0.89 versus AUC 0.81, 95% CI 0.78-0.84, respectively; p < 0.001) than the SAPS3 score alone.

CONCLUSIONS

Performance status and comorbidities are important determinants of short-term outcome in critically ill elderly patients ≥80 years old. The addition of simple background information may increase the calibration of the SAPS3 score in this population.

Admission factors associated with prolonged (>14 days) intensive care unit stay

PURPOSE

To describe the admission factors associated with prolonged (>14 days) intensive care unit (ICU) stay (PIS).

MATERIALS AND METHODS

Retrospective analysis of 3257 admissions during a 1.5-year period in a tertiary hospital. We tested the association between clinically relevant variables and PIS (>14 days) through binary logistic regression using the backward method. A Kaplan-Meier curve and the log-rank test were used to compare hospital outcomes for ICU survivors between patients with and without PIS.

RESULTS

In total, 6.6% of all admissions had a prolonged stay, consuming over 40% of all ICU bed-days. Illness severity; respiratory support at admission; performance status; readmission; admission from a ward, emergency room or other hospital; admission due to intracranial mass effect; severe chronic obstructive pulmonary disease; and the temperature at admission were all associated with PIS in a multivariate analysis. The created model had a good area under the curve (0.82) and was calibrated (Hosmer-Lemeshow test p = 0.431). Post hoc analysis on ICU survivors on in patients with at least two days of ICU stay yielded similar results. Hospital survival after ICU discharge was similar for patients with and without PIS (log-rank test p = 0.50).

CONCLUSION

A small number of ICU admissions consume a great proportion of ICU bed-days. Illness severity, a need for support and performance status are important predictors of PIS. Patients who survive a PIS have similar hospital mortality to patients with a shorter stay.

Improving the diagnosis of meningitis due to enterovirus and herpes simplex virus I and II in a tertiary care hospital

BACKGROUND

Enterovirus and herpes simplex viruses are common causes of lymphocytic meningitis. The purpose of this study was to analyse the impact of the use molecular testing for Enteroviruses and Herpes simplex viruses I and II in all suspected cases of viral meningitis.

METHODS

From November 18, 2008 to November 17, 2009 (phase II, intervention), all patients admitted with suspected viral meningitis (with pleocytosis) had a CSF sample tested using a nucleic acid amplification test (NAAT). Data collected during this period were compared to those from the previous one-year period, i.e. November 18, 2007 to November 17, 2008 (phase I, observational), when such tests were available but not routinely used.

RESULTS

In total, 2,536 CSF samples were assessed, of which 1,264 were from phase I, and 1,272 from phase II. Of this total, a NAAT for Enterovirus was ordered in 123 cases during phase I (9.7% of the total phase I sample) and in 221 cases in phase II (17.4% of the total phase II sample). From these, Enterovirus was confirmed in 35 (28.5%, 35/123) patients during phase I and 71 (32.1%, 71/221) patients during phase II (p = 0.107). The rate of diagnosis of meningitis by HSV I and II did not differ between the groups (13 patients, 6.5% in phase I and 13, 4.7% in phase II) (p = 1.0), from 200 cases in phase I and 274 cases in phase II.

CONCLUSIONS

The number of cases diagnosed with enteroviral meningitis increased during the course of this study, leading us to believe that the strategy of performing NAAT for Enterovirus on every CSF sample with pleocytosis is fully justified.

Prowess-shock trial: a protocol overview and perspectives

Sepsis remains a challenge for intensive care physicians, as it keeps up with high mortality rate in spite of the high costs associated with its treatment. Several studies indicate that the infusion of Drotrecogin-alpha activated (DrotAA) reduce mortality in patients at high risk of death when administered early and secured the appropriate initial treatment of sepsis as recommended by Surviving Sepsis Campaign. Europe and United States of America differ regarding the criteria of high risk of death in sepsis, two or more organ dysfunctions and Acute Physiology and Chronic Health Evaluation 25 or more, respectively. In addition to varied definitions of high risk of death for inclusion of patients in sepsis studies, the possibility of bleeding related to drug use and intrinsic limitations related to study design led the Company to develop a new randomized, multinational, placebo-controlled, double-blind study to assess the effectiveness of drug in patients with septic shock in adults.

Power spectral analysis of heart rate variability in HIV-infected and AIDS patients

BACKGROUND

In HIV-infected patients the risks for cardiovascular disease are multifactorial. Autonomic dysfunction has been detected in the early phase of HIV infection as well as in AIDS patients with advanced cardiomyopathy.

METHODS

Forty AIDS patients receiving highly active antiretroviral therapy (HAART), 40 HIV+ naïve of HAART, and 40 control subjects were studied. Computerized analysis of heart rate variability was performed using an analog to digital converter. R-R intervals were obtained from a standard ECG, recorded in DII lead in supine rest and after the cold-face and tilt tests. The series of R-R intervals were assessed in time and frequency domains using an autoregressive algorithm.

RESULTS

There was no difference regarding to mean values of R-R intervals and variance in baseline. The normalized power of the low-frequency (LF) component and the low-frequency/high-frequency (HF) ratio (LF/HF) was significantly decreased in the HIV group. Responses of normalized HF and LF/HF ratio during the cold-face test were significantly decreased in the HIV group, as compared to the control. During the tilt test, a higher augmentation of normalized LF and the LF/HF ratio was observed in the HIV group compared with the control. The AIDS group was similar to the control in baseline and after cold-face and tilt tests.

CONCLUSION

The HIV group presented in baseline conditions, a shift of cardiac sympathovagal balance, an exacerbated response of the LF component during the tilt test, and an ineffective cardiac vagal response to the cold-face test suggesting sympathetic and parasympathetic dysfunction. AIDS patients receiving HAART did not present these autonomic alterations.