Association of delayed adequate antimicrobial treatment and organ dysfunction in pediatric bloodstream infections

BACKGROUND

Bloodstream infections (BSIs) are associated with significant mortality and morbidity, including multiple organ dysfunction. We explored if delayed adequate antimicrobial treatment for children with BSIs is associated with change in organ dysfunction as measured by PELOD-2 scores.

METHODS

We conducted a multicenter, retrospective cohort study of critically ill children <18 years old with BSIs. The primary outcome was change in PELOD-2 score between days 1 (index blood culture) and 5. The exposure variable was delayed administration of adequate antimicrobial therapy by ≥3 h from blood culture collection. We compared PELOD-2 score changes between those who received early and delayed treatment.

RESULTS

Among 202 children, the median (interquartile range) time to adequate antimicrobial therapy was 7 (0.8-20.1) hours; 124 (61%) received delayed antimicrobial therapy. Patients who received early and delayed treatment had similar baseline characteristics. There was no significant difference in PELOD-2 score changes from days 1 and 5 between groups (PELOD-2 score difference -0.07, 95% CI -0.92 to 0.79, p = 0.88).

CONCLUSIONS

We did not find an association between delayed adequate antimicrobial therapy and PELOD-2 score changes between days 1 and 5 from detection of BSI. PELOD-2 score was not sensitive for clinical effects of delayed antimicrobial treatment.

IMPACT

In critically ill children with bloodstream infections, there was no significant change in organ dysfunction as measured by PELOD-2 scores between patients who received adequate antimicrobial therapy within 3 h of their initial positive blood culture and those who started after 3 h. Higher PELOD-2 scores on day 1 were associated with larger differences in PELOD-2 scores between days 1 and 5 from index positive blood cultures. Further study is required to determine if PELOD-2 or alternative measures of organ dysfunction could be used as primary outcome measures in trials of antimicrobial interventions in pediatric critical care research.

Antimicrobial treatment duration for uncomplicated bloodstream infections in critically ill children: a multicentre observational study

Background

Bloodstream infections (BSIs) cause significant morbidity and mortality in critically ill children but treatment duration is understudied. We describe the durations of antimicrobial treatment that critically ill children receive and explore factors associated with treatment duration.

Methods

We conducted a retrospective observational cohort study in six pediatric intensive care units (PICUs) across Canada. Associations between treatment duration and patient-, infection- and pathogen-related characteristics were explored using multivariable regression analyses.

Results

Among 187 critically ill children with BSIs, the median duration of antimicrobial treatment was 15 (IQR 11–25) days. Median treatment durations were longer than two weeks for all subjects with known sources of infection: catheter-related 16 (IQR 11–24), respiratory 15 (IQR 11–26), intra-abdominal 20 (IQR 14–26), skin/soft tissue 17 (IQR 15–33), urinary 17 (IQR 15–35), central nervous system 33 (IQR 15–46) and other sources 29.5 (IQR 15–55) days. When sources of infection were unclear, the median duration was 13 (IQR 10–16) days. Treatment durations varied widely within and across PICUs. In multivariable linear regression, longer treatment durations were associated with severity of illness (+ 0.4 days longer [95% confidence interval (CI), 0.1 to 0.7, p = 0.007] per unit increase in PRISM-IV) and central nervous system infection (+ 17 days [95% CI, 6.7 to 27.4], p = 0.001). Age and pathogen type were not associated with treatment duration.

Conclusions

Most critically ill children with BSIs received at least two weeks of antimicrobial treatment. Further study is needed to determine whether shorter duration therapy would be effective for selected critically ill children.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03219-z.

Bacteremia Antibiotic Length Actually Needed for Clinical Effectiveness (BALANCE) randomised clinical trial: study protocol

INTRODUCTION

Bloodstream infections are a leading cause of mortality and morbidity; the duration of treatment for these infections is understudied.

METHODS AND ANALYSIS

We will conduct an international, multicentre randomised clinical trial of shorter (7 days) versus longer (14 days) antibiotic treatment among hospitalised patients with bloodstream infections. The trial will include 3626 patients across 60 hospitals and 6 countries. We will include patients with blood cultures confirming a pathogenic bacterium after hospital admission. Exclusion criteria will include patient factors (severe immunosuppression), infection site factors (endocarditis, osteomyelitis, undrained abscesses, infected prosthetic material) and pathogen factors (Staphylococcus aureus, Staphylococcus lugdunensis, Candida and contaminant organisms). We will leave the selection of specific antibiotics, doses and route of delivery to the discretion of treating physicians; no placebo control will be used given the diversity of pathogens and sources of bacteraemia. The intervention will be assignment of treatment duration to be 7 versus 14 days. We will minimise selection bias via central randomisation with variable block sizes, with concealed allocation until day 7 of adequate antibiotic treatment. The primary outcome is 90-day survival; we will test whether 7 days is non-inferior to 14 days of treatment, with a non-inferiority margin of 4% absolute mortality. Secondary outcomes include hospital and intensive care unit (ICU) mortality, relapse rates of bacteraemia, hospital and ICU length of stay, mechanical ventilation and vasopressor duration, antibiotic-free days, Clostridium difficile infection, antibiotic allergy and adverse events and colonisation/infection with antibiotic-resistant organisms.

ETHICS AND DISSEMINATION

The study has been approved by the ethics review board at each participating site. Sunnybrook Health Sciences Centre is the central ethics committee. We will disseminate study results via the Canadian Critical Care Trials Group and other collaborating networks to set the global paradigm for antibiotic treatment duration for non-staphylococcal Gram-positive, Gram-negative and anaerobic bacteraemia, among patients admitted to hospital.

TRIAL REGISTRATION NUMBER

The BALANCE (Bacteremia Antibiotic Length Actually Needed for Clinical Effectiveness) trial was registered at www.clinicaltrials.gov (registration number: NCT03005145).

A pilot randomized controlled trial of 7 versus 14 days of antibiotic treatment for bloodstream infection on non-intensive care versus intensive care wards

BACKGROUND

The optimal treatment duration for patients with bloodstream infection is understudied. The Bacteremia Antibiotic Length Actually Needed for Clinical Effectiveness (BALANCE) pilot randomized clinical trial (RCT) determined that it was feasible to enroll and randomize intensive care unit (ICU) patients with bloodstream infection to 7 versus 14 days of treatment, and served as the vanguard for the ongoing BALANCE main RCT. We performed this BALANCE-Ward pilot RCT to examine the feasibility and impact of potentially extending the BALANCE main RCT to include patients hospitalized on non-ICU wards.

METHODS

We conducted an open pilot RCT among a subset of six sites participating in the ongoing BALANCE RCT, randomizing patients with positive non-Staphylococcus aureus blood cultures on non-ICU wards to 7 versus 14 days of antibiotic treatment. The co-primary feasibility outcomes were recruitment rate and adherence to treatment duration protocol. We compared feasibility outcomes, patient/pathogen characteristics, and overall outcomes among those enrolled in this BALANCE-Ward and prior BALANCE-ICU pilot RCTs. We estimated the sample size and non-inferiority margin impacts of expanding the BALANCE main RCT to include non-ICU patients.

RESULTS

A total of 134 patients were recruited over 47 site-months (mean 2.9 patients/site-month, median 1.0, range 0.1-4.4 patients/site-month). The overall recruitment rate exceeded the BALANCE-ICU pilot RCT (mean 1.10 patients/site-month, p < 0.0001). Overall protocol adherence also exceeded the adherence in the BALANCE-ICU pilot RCT (125/134, 93% vs 89/115, 77%, p = 0.0003). BALANCE-Ward patients were older, with lower Sequential Organ Failure Assessment scores, and higher proportions of infections caused by Escherichia coli and genito-urinary sources of bloodstream infection. The BALANCE-Ward pilot RCT patients had an overall 90-day mortality rate of 17/133 (12.8%), which was comparable to the 90-day mortality rate in the ICU pilot RCT (17/115, 14.8%) (p = 0.65). Simulation models indicated there would be minimal sample size and non-inferiority margin implications of expanding enrolment to increasing proportions of non-ICU versus ICU patients.

CONCLUSION

It is feasible to enroll non-ICU patients in a trial of 7 versus 14 days of antibiotics for bloodstream infection, and expanding the BALANCE RCT hospital-wide has the potential to improve the timeliness and generalizability of trial results.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT02917551. Registered on September 28, 2016.

7 versus 14 days of antibiotic treatment for critically ill patients with bloodstream infection: a pilot randomized clinical trial

Background

Shorter-duration antibiotic treatment is sufficient for a range of bacterial infections, but has not been adequately studied for bloodstream infections. Our systematic review, survey, and observational study indicated equipoise for a trial of 7 versus 14 days of antibiotic treatment for bloodstream infections; a pilot randomized clinical trial (RCT) was a necessary next step to assess feasibility of a larger trial.

Methods

We conducted an open, pilot RCT of antibiotic treatment duration among critically ill patients with bloodstream infection across 11 intensive care units (ICUs). Antibiotic selection, dosing and route were at the discretion of the treating team; patients were randomized 1:1 to intervention arms consisting of two fixed durations of treatment – 7 versus 14 days. We recruited adults with a positive blood culture yielding pathogenic bacteria identified while in ICU. We excluded patients with severe immunosuppression, foci of infection with an established requirement for prolonged treatment, single cultures with potential contaminants, or cultures yielding Staphylococcus aureus or fungi. The primary feasibility outcomes were recruitment rate and adherence to treatment duration protocol. Secondary outcomes included 90-day, ICU and hospital mortality, relapse of bacteremia, lengths of stay, mechanical ventilation and vasopressor duration, antibiotic-free days, Clostridium difficile, antibiotic adverse events, and secondary infection with antimicrobial-resistant organisms.

Results

We successfully achieved our target sample size (n = 115) and average recruitment rate of 1 (interquartile range (IQR) 0.3–1.5) patient/ICU/month. Adherence to treatment duration was achieved in 89/115 (77%) patients. Adherence differed by underlying source of infection: 26/31 (84%) lung; 18/29 (62%) intra-abdominal; 20/26 (77%) urinary tract; 8/9 (89%) vascular-catheter; 4/4 (100%) skin/soft tissue; 2/4 (50%) other; and 11/12 (92%) unknown sources. Patients experienced a median (IQR) 14 (8–17) antibiotic-free days (of the 28 days after blood culture collection). Antimicrobial-related adverse events included hepatitis in 1 (1%) patient, Clostridium difficile infection in 4 (4%), and secondary infection with highly resistant microorganisms in 10 (9%). Ascertainment was complete for all study outcomes in ICU, in hospital and at 90 days.

Conclusion

It is feasible to conduct a RCT to determine whether 7 versus 14 days of antibiotic treatment is associated with comparable 90-day survival.

Trial registration

ClinicalTrials.gov, identifier: NCT02261506. Registered on 26 September 2014.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2474-1) contains supplementary material, which is available to authorized users.

Time required to initiate outbreak and pandemic observational research

PURPOSE

Observational research focused upon emerging infectious diseases such as Ebola virus, Middle East respiratory syndrome, and Zika virus has been challenging to quickly initiate. We aimed to determine the duration of start-up procedures and barriers encountered for an observational study focused upon such infectious outbreaks.

MATERIALS AND METHODS

At 1 pediatric and 5 adult intensive care units, we measured durations from protocol receipt to a variety of outbreak research milestones, including research ethics board (REB) approval, data sharing agreement (DSA) execution, and patient study screening initiation.

RESULTS

The median (interquartile range) time from site receipt of the protocol to REB submission was 73 (30-126) days; to REB approval, 158 (42-188) days; to DSA completion, 276 (186-312) days; and to study screening initiation, 293 (269-391) days. The median time from REB submission to REB approval was 43 (13-85) days. The median time for all start-up procedures was 335 (188-335) days.

CONCLUSIONS

There is a lengthy start-up period required for outbreak-focused research. Completing DSAs was the most time-consuming step. A reactive approach to newly emerging threats such as Ebola virus, Middle East respiratory syndrome, and Zika virus will likely not allow sufficient time to initiate research before most outbreaks are advanced.

Pathogens and antimicrobial susceptibility profiles in critically ill patients with bloodstream infections: a descriptive study

BACKGROUND

Surveillance of antimicrobial resistance is vital to guiding empirical treatment of infections. Collating and reporting routine data on clinical isolate testing may offer more timely information about resistance patterns than traditional surveillance network methods.

METHODS

Using routine microbiology testing data collected from the Bacteremia Antibiotic Length Actually Needed for Clinical Effectiveness retrospective cohort study, we conducted a descriptive secondary analysis among critically ill patients in whom bloodstream infections had been diagnosed in 14 intensive care units (ICUs) in Canada. The participating sites were located within tertiary care teaching hospitals and represented 6 provinces and 10 cities. More than 80% of the study population was accrued from 2011-2013. We assessed the epidemiologic features of the infections and corresponding antimicrobial susceptibility profiles. Susceptibility testing was done according to Clinical Laboratory Standards Institute guidelines at accredited laboratories.

RESULTS

A total of 1416 pathogens were isolated from 1202 patients. The most common organisms were Escherichia coli (217 isolates [15.3%]), Staphylococcus aureus (175 [12.4%]), coagulase-negative staphylococci (117 [8.3%]), Klebsiella pneumoniae (86 [6.1%]) and Streptococcus pneumoniae (85 [6.0%]). The contribution of individual pathogens varied by site. For 13 ICUs, gram-negative susceptibility rates were high for carbapenems (95.4%), tobramycin (91.2%) and piperacillin-tazobactam (90.0%); however, the proportion of specimens susceptible to these agents ranged from 75.0%-100%, 66.7%-100% and 75.0%-100%, respectively, across sites. Fewer gram-negative bacteria were susceptible to fluoroquinolones (84.5% [range 64.1%-97.2%]). A total of 145 patients (12.1%) had infections caused by highly resistant microorganisms, with significant intersite variation (range 2.6%-24.0%, χ2 = 57.50, p < 0.001).

INTERPRETATION

We assessed the epidemiologic features of bloodstream infections in a geographically diverse cohort of critically ill Canadian patients using routine pathogen and susceptibility data extracted from readily available microbiology testing databases. Expanding data sharing across more ICUs, with serial measurement and prompt reporting, could provide much-needed guidance for empiric treatment for patients as well as system-wide prevention methods to limit antimicrobial resistance.

The Effect of Inadequate Initial Empiric Antimicrobial Treatment on Mortality in Critically Ill Patients with Bloodstream Infections: A Multi-Centre Retrospective Cohort Study

Hospital mortality rates are elevated in critically ill patients with bloodstream infections. Given that mortality may be even higher if appropriate treatment is delayed, we sought to determine the effect of inadequate initial empiric treatment on mortality in these patients. A retrospective cohort study was conducted across 13 intensive care units in Canada. We defined inadequate initial empiric treatment as not receiving at least one dose of an antimicrobial to which the causative pathogen(s) was susceptible within one day of initial blood culture. We evaluated the association between inadequate initial treatment and hospital mortality using a random effects multivariable logistic regression model. Among 1,190 patients (1,097 had bacteremia and 93 had candidemia), 476 (40%) died and 266 (22%) received inadequate initial treatment. Candidemic patients more often had inadequate initial empiric therapy (64.5% versus 18.8%), as well as longer delays to final culture results (4 vs 3 days) and appropriate therapy (2 vs 0 days). After adjustment, there was no detectable association between inadequate initial treatment and mortality among bacteremic patients (Odds Ratio (OR): 1.02, 95% Confidence Interval (CI) 0.70-1.48); however, candidemic patients receiving inadequate treatment had nearly three times the odds of death (OR: 2.89, 95% CI: 1.05-7.99). Inadequate initial empiric antimicrobial treatment was not associated with increased mortality in bacteremic patients, but was an important risk factor in the subgroup of candidemic patients. Further research is warranted to improve early diagnostic and risk prediction methods in candidemic patients.

Bacteremia Antibiotic Length Actually Needed for Clinical Effectiveness (BALANCE): study protocol for a pilot randomized controlled trial

Background

Bacteremia is a leading cause of mortality and morbidity in critically ill adults. No previous randomized controlled trials have directly compared shorter versus longer durations of antimicrobial treatment in these patients.

Methods/Design

This is a multicenter pilot randomized controlled trial in critically ill patients with bacteremia. Eligible patients will be adults with a positive blood culture with pathogenic bacteria identified while in the intensive care unit. Eligible, consented patients will be randomized to either 7 days or 14 days of adequate antimicrobial treatment for the causative pathogen(s) detected on blood cultures. The diversity of pathogens and treatment regimens precludes blinding of patient and clinicians, but allocation concealment will be extended to day 7 and outcome adjudicators will be blinded. The primary outcome for the main trial will be 90-day mortality. The primary outcome for the pilot trial is feasibility defined by (i) rate of recruitment exceeding 1 patient per site per month and (ii) adherence to treatment duration protocol ≥ 90%. Secondary outcomes include intensive care unit, hospital and 90-day mortality rates, relapse rates of bacteremia, antibiotic-related side effects and adverse events, rates of Clostridium difficile infection, rates of secondary infection or colonization with antimicrobial resistant organisms, ICU and hospital lengths of stay, mechanical ventilation and vasopressor duration in intensive care unit, and procalcitonin levels on the day of randomization, and day 7, 10 and 14 after the index blood culture.

Discussion

The BALANCE pilot trial will inform the design and execution of the subsequent BALANCE main trial, which will evaluate shorter versus longer duration treatment for bacteremia in critically ill patients, and thereby provide an evidence basis for treatment duration decisions for these infections.

Trial registration

The Pilot Trial was registered on 26 September 2014. Trial registration number: NCT02261506.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-015-0688-z) contains supplementary material, which is available to authorized users.

Serum procalcitonin in cirrhotic patients with septic shock: relationship with adrenal insufficiency and clinical outcomes

BACKGROUND

Serum procalcitonin is commonly used to differentiate systemic inflammation due to infection from non-infectious causes. Limited data exist on the value of procalcitonin in predicting relative adrenal insufficiency (RAI). This study evaluated the value of procalcitonin in predicting RAI and mortality in cirrhotic patients with septic shock.

METHODS

This was a post-hoc analysis of a randomized placebo-controlled trial that evaluated low-dose hydrocortisone in cirrhotic patients with septic shock. Extracted first study-day data included serum procalcitonin, baseline serum cortisol, cortisol level after 250 microg - adrenocorticotropic hormone stimulation test and 28 - day mortality. RAI was defined as a baseline serum cortisol < 10 microg/dL or cortisol not rising by > 9 microg/dL after stimulation. Procalcitonin > 0.5 ng/mL was considered high.

RESULTS

Forty-five patients had serum procalcitonin measured (mean = 2.7 +/- 3.2 ng/mL, first and third quartiles were 0.3 and 3.3 ng/mL, respectively). Most (78%) patients had high procalcitonin levels. RAI was present in 34 (76%) patients. Patients with high procalcitonin were more likely to have RAI (odds ratio, 4.8; 95% confidence interval, 1.1 - 22.1). Receiver operator characteristic curve analysis showed that the best cut-off for detecting RAI was 1.0 ng/mL (sensitivity = 79% and specificity = 55%). High serum procalcitonin was not associated with 28 -day mortality (80% for normal procalcitonin and 77% for high procalcitonin, p = 0.61).

CONCLUSIONS

High serum procalcitonin was highly associated with RAI in cirrhotic patients with septic shock. Procalcitonin was not associated with 28 - day mortality in this patient population.

Drug-resistant ventilator associated pneumonia in a tertiary care hospital in Saudi Arabia

BACKGROUND:

There is a wide geographic and temporal variability of bacterial resistance among microbial causes of ventilator-associated pneumonia (VAP). The contribution of multi-drug resistant (MDR) pathogens to the VAP etiology in Saudi Arabia was never studied. We sought to examine the extent of multiple-drug resistance among common microbial causes of VAP.

MATERIALS AND METHODS:

We conducted a retrospective susceptibility study in the adult intensive care unit (ICU) of King Abdulaziz Medical City, Riyadh, Saudi Arabia. Susceptibility results of isolates from patients diagnosed with VAP between October 2004 and June 2009 were examined. The US National Healthcare Safety Network definition of MDR was adopted.

RESULTS:

A total of 248 isolates including 9 different pathogens were included. Acinetobacter spp. was highly (60-89%) resistant to all tested antimicrobials, including carbapenems (three- and four-class MDR prevalence were 86% and 69%, respectively). Pseudomonas aeruginosa was moderately (13-31%) resistant to all tested antimicrobials, including antipseudomonal penicillins (three- and four-class MDR prevalence were 13% and 10%, respectively). With an exception of ampicillin (fully resistant), Klebsiella spp. had low (0-13%) resistance to other tested antimicrobials with no detected MDR. Staphylococcus aureus was fully susceptible to vancomycin with 42% resistance to oxacillin. There were significant increasing trends of MDR Acinetobacter spp. however not P. aeruginosa during the study. Resistant pathogens were associated with worse profile of ICU patients but not patients’ outcomes.

CONCLUSION:

Acinetobacter in the current study was an increasingly resistant VAP-associated pathogen more than seen in many parts of the world. The current finding may impact local choice of initial empiric antibiotics.

The association between statin therapy during intensive care unit stay and the incidence of venous thromboembolism: a propensity score-adjusted analysis

Background

Studies have shown that statins have pleiotropic effects on inflammation and coagulation; which may affect the risk of developing venous thromboembolism (VTE). The objective of this study was to evaluate the association between statin therapy during intensive care unit (ICU) stay and the incidence of VTE in critically ill patients.

Methods

This was a post-hoc analysis of a prospective observational cohort study of patients admitted to the intensive care unit between July 2006 and January 2008 at a tertiary care medical center. The primary endpoint was the incidence of VTE during ICU stay up to 30 days. Secondary endpoint was overall 30-day hospital mortality. Propensity score was used to adjust for clinically and statistically relevant variables.

Results

Of the 798 patients included in the original study, 123 patients (15.4%) received statins during their ICU stay. Survival analysis for VTE risk showed that statin therapy was not associated with a reduction of VTE incidence (crude hazard ratio (HR) 0.66, 95% confidence interval (CI) 0.28-1.54, P = 0.33 and adjusted HR 0.63, 95% CI 0.25-1.57, P = 0.33). Furthermore, survival analysis for hospital mortality showed that statin therapy was not associated with a reduction in hospital mortality (crude HR 1.26, 95% CI 0.95-1.68, P = 0.10 and adjusted HR 0.98, 95% CI 0.72-1.36, P = 0.94).

Conclusion

Our study showed no statistically significant association between statin therapy and VTE risk in critically ill patients. This question needs to be further studied in randomized control trials.

Even mild hyperlactatemia is associated with increased mortality in critically ill patients

Introduction

The clinical significance of elevation of lactate levels within the reference range is not well studied. The objective of this study was to determine the best cutoff threshold for serum lactate within the reference range (0.01 to 2.00 mM) that best discriminated between survivors and nonsurvivors of critical illness and to examine the association between relative hyperlactatemia (lactate above the identified threshold) and mortality.

Methods

This was a retrospective cohort study of adult patients admitted to the medical-surgical intensive care unit (ICU) of a tertiary care academic center. Youden index was calculated to identify the best lactate cutoff threshold that discriminated between survivors and nonsurvivors. Patients with lactate above the identified threshold were defined as having relative hyperlactatemia. Multivariate logistic regression, adjusting for baseline variables, was performed to determine the relationship between the above two ranges of lactate levels and mortality. In addition, a test of interaction was performed to assess the effect of selected subgroups on the association between relative hyperlactatemia and hospital mortality.

Results

During the study period, 2,157 patients were included in the study with mean lactate of 1.3 ± 0.4 mM, age of 55.1 ± 20.3 years, and acute physiology and chronic health evaluation (APACHE) II score of 22.1 ± 8.2. Vasopressors were required in 42.4%. Lactate of 1.35 mM was found to be the best cutoff threshold for the whole cohort. Relative hyperlactatemia was associated with increased hospital mortality (adjusted odds ratio (aOR), 1.60, 95% confidence interval (CI) 1.29 to 1.98), and ICU mortality (aOR, 1.66; 95% CI, 1.26 to 2.17) compared with a lactate level of 0.01 to 1.35 mM. This association was consistent among all examined subgroups.

Conclusions

Relative hyperlactatemia (lactate of 1.36 to 2.00 mM) within the first 24 hours of ICU admission is an independent predictor of hospital and ICU mortality in critically ill patients.

Demographics and outcomes of critically ill patients transferred from other hospitals to a tertiary care academic referral center in Saudi Arabia

Background

The objective of this study was to examine the outcomes of critically ill patients who were transferred from other hospitals to a tertiary care center in Saudi Arabia as a quality improvement project.

Methods

This was a retrospective study of adult patients admitted to the medical-surgical intensive care unit (ICU) of a tertiary care hospital. Patients were divided according to the source of referral into three groups: transfers from other hospitals, and direct admissions from emergency department (ED) and from hospital wards. Standardized mortality ratio (SMR) was calculated. Multivariate analysis was performed to determine the independent predictors of mortality.

Results

Of the 7,654 patients admitted to the ICU, 611 patients (8%) were transferred from other hospitals, 2,703 (35.3%) were direct admissions from ED and 4,340 (56.7%) from hospital wards. Hospital mortality for patients transferred from other hospitals was not significantly different from those who were directly admitted from ED (35% vs. 33.1%, p = 0.37) but was lower than those who were directly admitted from hospital wards (35% vs. 51.2%, p < 0.0001). SMRs did not differ significantly across the three groups.

Conclusions

Critically ill patients who were transferred from other hospitals constituted 8% of all ICU admissions. Mortality of these patients was similar to patients with direct admission from the ED and lower than that of patients with direct admission from hospital wards. However, risk-adjusted mortality was not different from the other two groups.

Clinical characteristics, sepsis interventions and outcomes in the obese patients with septic shock: an international multicenter cohort study

Introduction

Data are sparse as to whether obesity influences the risk of death in critically ill patients with septic shock. We sought to examine the possible impact of obesity, as assessed by body mass index (BMI), on hospital mortality in septic shock patients.

Methods

We performed a nested cohort study within a retrospective database of patients with septic shock conducted in 28 medical centers in Canada, United States and Saudi Arabia between 1996 and 2008. Patients were classified according to the World Health Organization criteria for BMI. Multivariate logistic regression analysis was performed to evaluate the association between obesity and hospital mortality.

Results

Of the 8,670 patients with septic shock, 2,882 (33.2%) had height and weight data recorded at ICU admission and constituted the study group. Obese patients were more likely to have skin and soft tissue infections and less likely to have pneumonia with predominantly Gram-positive microorganisms. Crystalloid and colloid resuscitation fluids in the first six hours were given at significantly lower volumes per kg in the obese and very obese patients compared to underweight and normal weight patients (for crystalloids: 55.0 ± 40.1 ml/kg for underweight, 43.2 ± 33.4 for normal BMI, 37.1 ± 30.8 for obese and 27.7 ± 22.0 for very obese). Antimicrobial doses per kg were also different among BMI groups. Crude analysis showed that obese and very obese patients had lower hospital mortality compared to normal weight patients (odds ratio (OR) 0.80, 95% confidence interval (CI) 0.66 to 0.97 for obese and OR 0.61, 95% CI 0.44 to 0.85 for very obese patients). After adjusting for baseline characteristics and sepsis interventions, the association became non-significant (OR 0.80, 95% CI 0.62 to 1.02 for obese and OR 0.69, 95% CI 0.45 to 1.04 for very obese).

Conclusions

The obesity paradox (lower mortality in the obese) documented in other populations is also observed in septic shock. This may be related in part to differences in patient characteristics. However, the true paradox may lie in the variations in the sepsis interventions, such as the administration of resuscitation fluids and antimicrobial therapy. Considering the obesity epidemic and its impact on critical care, further studies are warranted to examine whether a weight-based approach to common therapeutic interventions in septic shock influences outcome.

The results of a 6-year epidemiologic surveillance for ventilator-associated pneumonia at a tertiary care intensive care unit in Saudi Arabia

BACKGROUND

Ventilator-associated pneumonia (VAP) prevention is an important patient safety initiative. We describe the impact of a multidisciplinary surveillance program on VAP rates in a tertiary medical-surgical-trauma intensive care unit (ICU).

METHODS

An epidemiologic surveillance program was established in 2003 as a joint project between ICU and Infection Prevention and Control Department to regularly report VAP rates to guide evidence-based VAP preventive strategies. VAP cases were diagnosed according to predefined criteria and prospectively recorded by a research physician. VAP microbiology, risk factors, and outcomes were noted.

RESULTS

Of 2,812 ventilated patients, 433 (15.4%) developed VAP corresponding to 15.9 episodes per 1,000 ventilator-days. The rate decreased from 19.1 in 2003 to 6.3 per 1,000 ventilator-days in 2009. On multivariate analysis, VAP was associated with accidental extubation (hazard ratio [HR], 4.11; 95% confidence interval [CI]: 1.93-8.73), trauma versus medical diagnosis (HR, 2.59; 95% CI: 2.07-3.23), chronic obstructive pulmonary disease (HR, 1.55; 95% CI: 1.08-2.22), and neuromuscular blockade (HR, 1.39; 95% CI: 1.07-1.81). The most common isolated pathogens were Gram-negative organisms. VAP patients had longer mechanical ventilation duration, ICU and hospital length of stay, but similar ICU and hospital mortality compared with non-VAP patients.

CONCLUSION

The study showed a reduction in VAP rates with active surveillance, reporting and evidence-based preventive strategies and identified several modifiable risk factors, which should be the focus of additional interventions.

What is the optimal blood glucose target in critically ill patients? A nested cohort study

AIMS:

There is an uncertainty about what constitutes an optimal level of blood glucose (BG) in critically ill patients. The objective of this study is to identify the optimal BG target for glycemic control in critically ill patients that is associated with survival benefit with the least hypoglycemia risk.

SETTING AND DESIGN:

This is a nested cohort study within a randomized control trial conducted in a tertiary care center in King Abdulaziz Medical City, Riyadh, Kingdom of Saudi Arabia.

METHODS:

The study was carried out in a single center to assess the effect of intensive insulin therapy [IIT; target BG 4.4-6.1 mmol/L (80-110 mg/dL)] versus conventional insulin therapy [CIT; target BG 10-11.1 mmol/L (180-200 mg/dL)] in a medical/surgical ICU. All patients were divided into six groups based on the mean daily BG levels. A logistic regression model was used to determine the association of BG and ICU mortality. We compared different outcomes below and above different BG thresholds of 0.1 mmol/L (2 mg/dL) increments using multivariate analyses.

STATISTICAL ANALYSIS:

Data are presented as mean ± SD or median with interquartile ranges, unless otherwise indicated. Differences between the six groups were assessed using the χ² test. A P-value equal or less than 0.05 was considered to indicate statistical significance. The results were expressed as adjusted odds ratio (aOR) and 95% confidence intervals (CI). Statistical analyses were carried out using the Statistical Analysis Software (SAS, release 8, SAS Institute Inc., Cary, NC, USA).

RESULTS:

Among six groups, the ICU mortality was least in patients with BG <8.7 mmol/L (<157 mg/dL) compared with patients with BG ≥8.7 mmol/L (≥157 mg/dL) [11.5% vs. 21.5%, P = 0.002]. When analyzed using 0.1 mmol increments in average BG, we found that mortality remained unchanged by increasing thresholds of BG up to 8.0 mmol/L (144 mg/dL) and started to rise with thresholds of BG of 8.1 mmol/L (146 mg/dL) and above. The risk of hypoglycemia was the highest with a BG threshold of 6.1 mmol/L (110 mg/dL) and gradually decreased with increasing BG levels to plateau with a BG level of 7.2 mmol/L (130 mg/dL) and higher.

CONCLUSION:

Our study suggests that a BG level of 8.1 mmol/L (146 mg/dL) and below represents an optimal level in critically ill patients.

Intra-abdominal pressure and abdominal perfusion pressure in cirrhotic patients with septic shock

BACKGROUND

The importance of intra-abdominal pressure (IAP) and abdominal perfusion pressure (APP) in cirrhotic patients with septic shock is not well studied. We evaluated the relationship between IAP and APP and outcomes of cirrhotic septic patients, and assessed the ability of these measures compared to other common resuscitative endpoints to differentiate survivors from nonsurvivors.

METHODS

This study was a post hoc analysis of a randomized double-blind placebo-controlled trial in which mean arterial pressure (MAP), central venous oxygen saturation (ScvO2) and IAP were measured every 6 h in 61 cirrhotic septic patients admitted to the intensive care unit. APP was calculated as MAP - IAP. Intra-abdominal hypertension (IAH) was defined as mean IAP ≥ 12 mmHg, and abdominal hypoperfusion as mean APP < 60 mmHg. Measured outcomes included ICU and hospital mortality, need for renal replacement therapy (RRT) and ventilator- and vasopressor-free days.

RESULTS

IAH prevalence on the first ICU day was 82%, and incidence in the first 7 days was 97%. Compared to patients with normal IAP, IAH patients had significantly higher ICU mortality (74.0% vs. 27.3%, p = 0.005), required more RRT (78.0% vs. 45.5%, p = 0.06) and had lower ventilator- and vasopressor-free days. On a multivariate logistic regression analysis, IAH was an independent predictor of both ICU mortality (odds ratio (OR), 12.20; 95% confidence interval (CI), 1.92 to 77.31, p = 0.008) and need for RRT (OR, 6.78; 95% CI, 1.29 to 35.70, p = 0.02). Using receiver operating characteristic curves, IAP (area under the curve (AUC) = 0.74, p = 0.004), APP (AUC = 0.71, p = 0.01), Acute Physiology and Chronic Health Evaluation II score (AUC = 0.71, p = 0.02), but not MAP, differentiated survivors from nonsurvivors.

CONCLUSIONS

IAH is highly prevalent in cirrhotic patients with septic shock and is associated with increased ICU morbidity and mortality.

End-of-life practices in a tertiary intensive care unit in Saudi Arabia

Our aim was to evaluate end-of-life practices in a tertiary intensive care unit in Saudi Arabia. A prospective observational study was conducted in the medical-surgical intensive care unit of a teaching hospital in Riyadh, Saudi Arabia. Over the course of the one-year study period, 176 patients died and 77% of these deaths were preceded by end-of-life decisions. Of these, 66% made do-not-resuscitate decisions, 30% decided to withhold life support and 4% withdrew life support. These decisions were made after a median time of four days (Q1 to Q3: 1 to 9) and at least one day before death (Q1 to Q3: 1 to 4). The patients' families or surrogates were informed for 88% of the decisions and all decisions were documented in the patients' medical records. Despite religious and cultural values, more than three-quarters of the patients whose deaths were preceded by end-of-life decisions gave do-not-resuscitate decisions before death. These decisions should be made early in the patients' stay in the intensive care unit.

Etomidate and mortality in cirrhotic patients with septic shock

BACKGROUND

Clinical effects and outcomes of a single dose etomidate prior to intubation in the intensive care setting is controversial. The aim of this study is to evaluate the association of a single dose effect of etomidate prior to intubation on the mortality of septic cirrhotic patients and the impact of the subsequent use of low dose hydrocortisone.

METHODS

This is a nested-cohort study within a randomized double blind placebo controlled study evaluating the use of low dose hydrocortisone in cirrhotic septic patients. Cirrhotic septic patients ≥ 18 years were included in the study. Patients who received etomidate prior to intubation were compared to those who did not receive etomidate for all cause 28-day mortality as a primary outcome.

RESULTS

Sixty two intubated patients out of the 75 patients randomized in the initial trial were eligible for this study. Twenty three of the 62 intubated patients received etomidate dose prior to intubation. Etomidate use was not associated with all cause 28-day mortality or hospital mortality but was associated with significantly higher ICU mortality (91% vs. 64% for etomidate and controls groups, respectively; p = 0.02). Etomidate patients who received subsequent doses of hydrocortisone required lower doses of vasopressors and had more vasopressor-free days but no improvement in mortality.

CONCLUSIONS

In this group of septic cirrhotic patients with very high mortality, etomidate increased ICU mortality. Subsequent use of hydrocortisone appears to have no benefit beyond decreasing vasopressor requirements. The lowest mortality was observed in patients who did not receive etomidate but received hydrocortisone.

sRAGE in diabetic and non-diabetic critically ill patients: effects of intensive insulin therapy

Introduction

Hyperglycemia represents an independent prognostic factor in critically ill non-diabetic patients but not in those with diabetes. In this context, there is an ongoing debate on the benefit of an intensive insulin therapy, particularly in diabetic patients. We tested the hypothesis that expression of the receptor for advanced glycation end-products (RAGE), an important signal transduction receptor that elicits long-lasting nuclear factor kappa B (NF-κB) activation, may underlie this difference. RAGE expression is regulated by multiple ligands, including high mobility group box-1 (HMGB-1), and is reflected by its released soluble form (sRAGE).

Methods

A predesigned analysis was conducted of prospectively collected samples from 76 hyperglycemic critically ill patients (33 type-2 diabetes, 43 non-diabetes) aged ≥18 years with blood glucose of > 6.1 mmol/L enrolled in a randomized controlled trial comparing intensive insulin therapy with conventional insulin therapy. sRAGE and its ligand HMGB-1 together with IL-6, and soluble thrombomodulin (as markers of inflammation and endothelial cell injury, respectively) were evaluated in ICU, at Days 1, 3, 5 and 7. Plasma samples from 18 healthy subjects were used as controls.

Results

Both diabetic and non-diabetic hyperglycemic patients showed increased plasma sRAGE, HMGB-1 and soluble thrombomodulin levels at the time of admission to ICU. Plasma IL-6 concentration was only increased in non-diabetic patients. Plasma levels of sRAGE were higher in diabetic compared with non-diabetic patients. Intensive insulin therapy resulted in a significant decrease of sRAGE and thrombomodulin at Day 7, in diabetic but not in non-diabetic patients. Circulating sRAGE levels correlated positively with IL-6 and soluble thrombomodulin levels and inversely with HMGB-1. Multivariate regression analysis demonstrated that sRAGE remains independently correlated with HMGB-1 only in diabetic patients. Neither sRAGE nor any inflammatory markers are associated with mortality.

Conclusions

These findings support the hypothesis that sRAGE release, time-course and response to intensive insulin therapy differ between hyperglycemic diabetic and non-diabetic critically ill patients. Whether this difference underlies the dissimilarity in clinical outcome of hyperglycemia in these two conditions warrants further studies.

Low-dose hydrocortisone in patients with cirrhosis and septic shock: a randomized controlled trial

BACKGROUND

Recent studies have reported a high prevalence of relative adrenal insufficiency in patients with liver cirrhosis. However, the effect of corticosteroid replacement on mortality in this high-risk group remains unclear. We examined the effect of low-dose hydrocortisone in patients with cirrhosis who presented with septic shock.

METHODS

We enrolled patients with cirrhosis and septic shock aged 18 years or older in a randomized double-blind placebo-controlled trial. Relative adrenal insufficiency was defined as a serum cortisol increase of less than 250 nmol/L or 9 μg/dL from baseline after stimulation with 250 μg of intravenous corticotropin. Patients were assigned to receive 50 mg of intravenous hydrocortisone or placebo every six hours until hemodynamic stability was achieved, followed by steroid tapering over eight days. The primary outcome was 28-day all-cause mortality.

RESULTS

The trial was stopped for futility at interim analysis after 75 patients were enrolled. Relative adrenal insufficiency was diagnosed in 76% of patients. Compared with the placebo group (n = 36), patients in the hydrocortisone group (n = 39) had a significant reduction in vasopressor doses and higher rates of shock reversal (relative risk [RR] 1.58, 95% confidence interval [CI] 0.98-2.55, p = 0.05). Hydrocortisone use was not associated with a reduction in 28-day mortality (RR 1.17, 95% CI 0.92-1.49, p = 0.19) but was associated with an increase in shock relapse (RR 2.58, 95% CI 1.04-6.45, p = 0.03) and gastrointestinal bleeding (RR 3.00, 95% CI 1.08-8.36, p = 0.02).

INTERPRETATION

Relative adrenal insufficiency was very common in patients with cirrhosis presenting with septic shock. Despite initial favourable effects on hemodynamic parameters, hydrocortisone therapy did not reduce mortality and was associated with an increase in adverse effects. (Current Controlled Trials registry no. ISRCTN99675218.).

Near-target caloric intake in critically ill medical-surgical patients is associated with adverse outcomes

BACKGROUND

The objective of this study was to determine whether caloric intake independently influences mortality and morbidity of critically ill patients.

METHODS

The study was conducted as a nested cohort study within a randomized controlled trial in a tertiary care intensive care unit (ICU). The main exposure in the study was average caloric intake/target for the first 7 ICU days. The primary outcomes were ICU and hospital mortality. Secondary outcomes included ICU-acquired infections, ventilator-associated pneumonia (VAP), duration of mechanical ventilation days, and ICU and hospital length of stay (LOS). The authors divided patients (n = 523) into 3 tertiles according to the percentage of caloric intake/target: tertile I <33.4%, tertile II 33.4%-64.6%, and tertile III >64.6%. To adjust for potentially confounding variables, the authors assessed the association between caloric intake/target and the different outcomes using multivariate logistic regression for categorical outcomes (tertile I was used as reference) and multiple linear regression for continuous outcomes.

RESULTS

Tertile III was associated with higher adjusted hospital mortality, higher risk of ICU-acquired infections, and a trend toward higher VAP rate. Increasing caloric intake was independently associated with a significant increase in duration of mechanical ventilation, ICU LOS, and hospital LOS.

CONCLUSIONS

The data demonstrate that near-target caloric intake is associated with significantly increased hospital mortality, ICU-acquired infections, mechanical ventilation duration, and ICU and hospital LOS. Further studies are needed to explore whether reducing caloric intake would improve the outcomes in critically ill patients.

Intensive insulin therapy versus conventional insulin therapy for critically ill trauma patients admitted to ICU

PURPOSE

The objective of our study was to evaluate the beneficial effect of IIT in reducing mortality and morbidity in critically ill trauma patients admitted to ICU.

METHOD AND MATERIAL

Nested cohort study within a Randomized Controlled Trial. All trauma patients with GCS < or = 9 included in the original trial were included in this study. Primary outcome was ICU mortality.

RESULT

There was no difference in ICU mortality between IIT and CIT groups (6.5% vs. 5.5%, p = 0.67). After adjustment for baseline characteristics, IIT therapy was also not associated with mortality (Adjusted Hazard Ratio 1.33, 95% CI 0.35-5.05). IIT therapy was associated with a significant increase in the incidence of hypoglycemia as compared to CIT, at least one hypoglycemia episode occurred in 18.5% of patients in IIT and 1.3% in the CIT group (P < 0.0001).

CONCLUSION

IIT was not associated with survival improvement in trauma patients admitted to ICU and was associated with increased incidence of hypoglycemia.