Christopher MacIsaac

Prognostic Accuracy of the SOFA Score, SIRS Criteria, and qSOFA Score for In-Hospital Mortality Among Adults With Suspected Infection Admitted to the Intensive Care Unit

Importance The Sepsis-3 Criteria emphasized the value of a change of 2 or more points in the Sequential [Sepsis-related] Organ Failure Assessment (SOFA) score, introduced quick SOFA (qSOFA), and removed the systemic inflammatory response syndrome (SIRS) criteria from the sepsis definition. Objective Externally validate and assess the discriminatory capacities of an increase in SOFA score by 2 or more points, 2 or more SIRS criteria, or a qSOFA score of 2 or more points for outcomes among patients who are critically ill with suspected infection. Design, Setting, and Participants Retrospective cohort analysis of 184 875 patients with an infection-related primary admission diagnosis in 182 Australian and New Zealand intensive care units (ICUs) from 2000 through 2015. Exposures SOFA, qSOFA, and SIRS criteria applied to data collected within 24 hours of ICU admission. Main Outcomes and Measures The primary outcome was in-hospital mortality. In-hospital mortality or ICU length of stay (LOS) of 3 days or more was a composite secondary outcome. Discrimination was assessed using the area under the receiver operating characteristic curve (AUROC). Adjusted analyses were performed using a model of baseline risk determined using variables independent of the scoring systems. Results Among 184 875 patients (mean age, 62.9 years [SD, 17.4]; women, 82 540 [44.6%]; most common diagnosis bacterial pneumonia, 32 634 [17.7%]), a total of 34 578 patients (18.7%) died in the hospital, and 102 976 patients (55.7%) died or experienced an ICU LOS of 3 days or more. SOFA score increased by 2 or more points in 90.1%; 86.7% manifested 2 or more SIRS criteria, and 54.4% had a qSOFA score of 2 or more points. SOFA demonstrated significantly greater discrimination for in-hospital mortality (crude AUROC, 0.753 [99% CI, 0.750-0.757]) than SIRS criteria (crude AUROC, 0.589 [99% CI, 0.585-0.593]) or qSOFA (crude AUROC, 0.607 [99% CI, 0.603-0.611]). Incremental improvements were 0.164 (99% CI, 0.159-0.169) for SOFA vs SIRS criteria and 0.146 (99% CI, 0.142-0.151) for SOFA vs qSOFA (P <.001). SOFA (AUROC, 0.736 [99% CI, 0.733-0.739]) outperformed the other scores for the secondary end point (SIRS criteria: AUROC, 0.609 [99% CI, 0.606-0.612]; qSOFA: AUROC, 0.606 [99% CI, 0.602-0.609]). Incremental improvements were 0.127 (99% CI, 0.123-0.131) for SOFA vs SIRS criteria and 0.131 (99% CI, 0.127-0.134) for SOFA vs qSOFA (P <.001). Findings were consistent for both outcomes in multiple sensitivity analyses. Conclusions and Relevance Among adults with suspected infection admitted to an ICU, an increase in SOFA score of 2 or more had greater prognostic accuracy for in-hospital mortality than SIRS criteria or the qSOFA score. These findings suggest that SIRS criteria and qSOFA may have limited utility for predicting mortality in an ICU setting.

The incidence of acute kidney injury in patients with traumatic brain injury

There is limited information on the incidence of acute kidney injury (AKI) in patients with traumatic brain injury (TBI) although AKI may contribute to morbidity and mortality. We investigated the incidence of AKI in patients with moderate and severe TBI and the association of AKI with risk factors and outcomes in these patients. We studied all TBI patients over 16 years of age admitted to the two designated trauma hospitals in the state of Victoria, Australia from 1 January to 31 December 2008. Patients were included if they had head trauma and presented with a Glasgow coma scale (GCS) <13. Prospectively collected data from the hospital trauma registries, ICUs, and pathology databases were analyzed retrospectively. Risk injury failure loss end (RIFLE) criteria were used to categorize renal function. The incidence of AKI was 9.2% (19/207). Patients who developed AKI were older, had higher severity of illness scores, and a lower GCS. Overall 42.1% of these patients died in hospital compared with 18.1% in patients without AKI. In univariable linear regression analysis, age, severity of illness, and admitting hospital were associated with AKI. After multivariable logistic regression, the occurrence of AKI was associated with age (p < 0.001) and higher APACHE III scores (p = 0.016). AKI is relatively common even in patients with TBI. Its association with age and APACHE III scores helps identify patients at higher risk of AKI.

Rapid analysis of the Vβ repertoire of CD4 and CD8 T lymphocytes in whole blood

Determination of the T cell receptor Vbeta repertoire of human CD4 and CD8 populations is a useful immunological tool, particularly in the investigation of superantigen involvement in various disease states. We describe the optimisation of a rapid technique for the simultaneous evaluation of 24 Vbeta families of the T cell receptor of CD4 and CD8 positive lymphocytes in whole blood by flow cytometry adapting a commercially available monoclonal antibody kit. The technique described is reliable and reproducible, and we describe its use as a potential diagnostic tool in patients with staphylococcal and streptococcal toxic shock syndromes.

The microbiology and outcome of sepsis in Victoria, Australia

We analysed data from 33741 patients with ICD-10-AM-defined sepsis from an Australian hospital morbidity dataset to investigate the relationships between specific types of organisms, potential risk factors for infection, organ dysfunction, ICU utilization and hospital mortality. A total of 24% of patients received some of their care in an intensive care unit, and the overall hospital mortality rate was 18%. Gram-positive bacteria were isolated in 27% of cases and Gram-negative bacteria in 20%. Sepsis due to Staphylococcus aureus was associated with vascular and joint devices whereas Pseudomonas aeruginosa and Gram-negative rods were more common with genitourinary devices and lymphoproliferative disease. Sepsis-associated organ dysfunction most commonly involved the respiratory system, followed by the renal and circulatory systems. These patterns may provide useful clues to the pathogenesis and therapy of this often fatal syndrome which is a major ongoing problem for hospitalized patients.

Medication Chart Intervention Improves Inpatient Thromboembolism Prophylaxis

BACKGROUND Inpatient VTE prophylaxis is underused. This study evaluated the effectiveness of the low-cost, multifaceted Australian National Inpatient Medication Chart (NIMC) intervention on improving the quality of VTE prophylaxis and reducing disease. The NIMC intervention incorporated (1) a VTE risk stratification and appropriate prophylaxis guidance tool, (2) a prophylaxis contraindication screening instrument, and (3) a prophylaxis prescription prompt. METHODS Retrospective analysis of 2,371 consecutive medical and surgical admissions was performed at a regional referral hospital over 1 year both before and after the intervention. Outcomes measured included the frequency of prophylaxis use, timing of prophylaxis initiation, adherence of the prescribed prophylaxis regimen to guidelines, incidence of VTE disease, and prophylaxis-related complications. RESULTS Following NIMC intervention, prophylaxis use increased from 52.7% to 66.5% in medical patients and from 77.5% to 89.1% in surgical patients (P < .001). This increase was still evident 12 months postintervention. After intervention, prophylaxis initiated on admission increased from 65.0% to 83.6% in medical patients and from 60.7% to 78.0% in surgical patients (P < .01); adherence rates to recommended guidelines increased from 55.6% to 71.0% in medical patients and from 53.6% to 75.6% in surgical patients (P < .01). More VTE risk factors independently triggered prophylaxis usage postintervention. The improved quality of prophylaxis did not significantly reduce VTE incidence (risk ratio, 0.88; 95% CI, 0.48-1.62). The rate of prophylaxis-related complications remained similar before and after intervention. CONCLUSIONS The multifaceted NIMC intervention resulted in a sustained increase in appropriate and timely VTE prophylaxis in medical and surgical inpatients.

Sticking to minimum standards: implementing antibiotic stewardship in intensive care.

In Australia, antimicrobial stewardship programmes are a compulsory component of hospital accreditation. Good documentation around anti‐microbial prescribing aids communication and can improve prescribing practice in environments with multiple decision makers.

The Melbourne epidemic thunderstorm asthma event 2016: an investigation of environmental triggers, effect on health services, and patient risk factors

BACKGROUND A multidisciplinary collaboration investigated the worlds largest, most catastrophic epidemic thunderstorm asthma event that took place in Melbourne, Australia, on Nov 21, 2016, to inform mechanisms and preventive strategies. METHODS Meteorological and airborne pollen data, satellite-derived vegetation index, ambulance callouts, emergency department presentations, and data on hospital admissions for Nov 21, 2016, as well as leading up to and following the event were collected between Nov 21, 2016, and March 31, 2017, and analysed. We contacted patients who presented during the epidemic thunderstorm asthma event at eight metropolitan health services (each including up to three hospitals) via telephone questionnaire to determine patient characteristics, and investigated outcomes of intensive care unit (ICU) admissions. FINDINGS Grass pollen concentrations on Nov 21, 2016, were extremely high (>100 grains/m3). At 1800 AEDT, a gust front crossed Melbourne, plunging temperatures 10°C, raising humidity above 70%, and concentrating particulate matter. Within 30 h, there were 3365 (672%) excess respiratory-related presentations to emergency departments, and 476 (992%) excess asthma-related admissions to hospital, especially individuals of Indian or Sri Lankan birth (10% vs 1%, p<0·0001) and south-east Asian birth (8% vs 1%, p<0·0001) compared with previous 3 years. Questionnaire data from 1435 (64%) of 2248 emergency department presentations showed a mean age of 32·0 years (SD 18·6), 56% of whom were male. Only 28% had current doctor-diagnosed asthma. 39% of the presentations were of Asian or Indian ethnicity (25% of the Melbourne population were of this ethnicity according to the 2016 census, relative risk [RR] 1·93, 95% CI 1·74-2·15, p <0·0001). Of ten individuals who died, six were Asian or Indian (RR 4·54, 95% CI 1·28-16·09; p=0·01). 35 individuals were admitted to an intensive care unit, all had asthma, 12 took inhaled preventers, and five died. INTERPRETATION Convergent environmental factors triggered a thunderstorm asthma epidemic of unprecedented magnitude, tempo, and geographical range and severity on Nov 21, 2016, creating a new benchmark for emergency and health service escalation. Asian or Indian ethnicity and current doctor-diagnosed asthma portended life-threatening exacerbations such as those requiring admission to an ICU. Overall, the findings provide important public health lessons applicable to future event forecasting, health care response coordination, protection of at-risk populations, and medical management of epidemic thunderstorm asthma. FUNDING None.

Targeted Full Energy and Protein Delivery in Critically Ill Patients: A Pilot Randomized Controlled Trial (FEED Trial)

BACKGROUND International guidelines recommend greater protein delivery to critically ill patients than they currently receive. This pilot randomized clinical trial aimed to determine whether a volume-target enteral protocol with supplemental protein delivered greater amounts of protein and energy to critically ill patients compared with standard care. METHODS Sixty participants received either the intervention (volume-based protocol, with protein supplementation) or standard nutrition care (hourly-rate-based protocol, without protein supplementation) in the intensive care unit (ICU). Coprimary outcomes were average daily protein and energy delivery. Secondary outcomes included change in quadriceps muscle layer thickness (QMLT, ultrasound) and malnutrition (subjective global assessment) at ICU discharge. RESULTS Mean (SD) protein and energy delivery per day from nutrition therapy for the intervention were 1.2 (0.30) g/kg and 21 (5.2) kcal/kg compared with 0.75 (0.11) g/kg and 18 (2.7) kcal/kg for standard care. The mean difference between groups in protein and energy delivery per day was 0.45 g/kg (95% CI, 0.33-0.56; P < .001) and 2.8 kcal/kg (95% CI, 0.67-4.9, P = .01). Muscle loss (QMLT) at discharge was attenuated by 0.22 cm (95% CI, 0.06-0.38, P = .01) in patients receiving the intervention compared with standard care. The number of malnourished patients was fewer in the intervention [2 (7%) vs 8 (28%); P = .04]. Mortality and duration of admission were similar between groups. CONCLUSIONS A high-protein volume-based protocol with protein supplementation delivered greater amounts of protein and energy. This intervention was associated with attenuation of QMLT loss and reduced prevalence of malnutrition at ICU discharge.