Beta-hydroxy-beta-methylbutyrate supplementation and functional outcomes in multitrauma patients: A pilot randomized controlled trial

BACKGROUND

Beta-hydroxy-beta-methylbutyrate (HMB) is a nutrition supplement that may attenuate muscle wasting from critical illness. This trial aimed to determine feasibility of administering a blinded nutrition supplement in the intensive care unit (ICU) and continuing it after ICU discharge.

METHODS

Single-center, parallel-group, blinded, placebo-controlled, randomized feasibility trial. After traumatic injury necessitating admission to ICU, participants were randomized to receive an enteral study supplement of 3 g of HMB (intervention) or placebo daily for 28 days or until hospital discharge. Primary outcome was feasibility of administering the study supplement, quantified as protocol adherence. Secondary outcomes included change in quadriceps muscle thickness, measured weekly until day 28 or hospital discharge by using ultrasound and analyzed by using a linear mixed model.

RESULTS

Fifty randomized participants (intervention, n = 26; placebo, n = 24) showed comparable baseline characteristics. Participants received 862 (84.3%) of the 1022 prescribed supplements during hospitalization with 543 (62.8%) delivered via an enteral feeding tube. The median (IQR) number of study supplements successfully administered per participant was 19.5 (13.0-24.0) in the intervention group and 16.5 (8.5-23.5) in the placebo group. Marked loss of quadriceps muscle thickness occurred in both groups, with the point estimate favoring attenuated muscle loss with the intervention, albeit with wide CIs (mean intervention difference after 28 days, 0.26 cm [95% CI, -0.13 to 0.64]).

CONCLUSION

A blinded, placebo-controlled, randomized clinical trial of daily enteral HMB supplementation for up to 28 days in hospital is feasible. Any effect of HMB supplementation to attenuate muscle wasting after traumatic injury remains uncertain.

Study protocol for TARGET protein: The effect of augmented administration of enteral protein to critically ill adults on clinical outcomes: A cluster randomised, cross-sectional, double cross-over, clinical trial

Background

It is unknown whether increasing dietary protein to 1.2-2.0 g/kg/day as recommended in international guidelines compared to current practice improves outcomes in intensive care unit (ICU) patients. The TARGET Protein trial will evaluate this.

Objective

To describe the study protocol for the TARGET Protein trial.

Design setting and participants

TARGET Protein is a cluster randomised, cross-sectional, double cross-over, pragmatic clinical trial undertaken in eight ICUs in Australia and New Zealand. Each ICU will be randomised to use one of two trial enteral formulae for three months before crossing over to the other formula, which is then repeated, with enrolment continuing at each ICU for 12 months. All patients aged ≥16 years in their index ICU admission commencing enteral nutrition will be eligible for inclusion. Eligible patients will receive the trial enteral formula to which their ICU is allocated. The two trial enteral formulae are isocaloric with a difference in protein dose: intervention 100g/1000 ml and comparator 63g/1000 ml. Staggered recruitment commenced in May 2022.

Main outcomes measures

The primary outcome is days free of the index hospital and alive at day 90. Secondary outcomes include days free of the index hospital at day 90 in survivors, alive at day 90, duration of invasive ventilation, ICU and hospital length of stay, incidence of tracheostomy insertion, renal replacement therapy, and discharge destination.

Conclusion

TARGET Protein aims to determine whether augmented enteral protein delivery reduces days free of the index hospital and alive at day 90.

Trial registration

Australian New Zealand Clinical Trials Registry (ACTRN12621001484831).

Aggression, violence and threatening behaviour during critical illness

Objective

This article aims to quantify prevalence of patient aggression or threatened/actual violence during critical illness.

Design

This is a retrospective cohort study.

Setting

This study was conducted in single adult trauma intensive care unit (ICU).

Participants

Patients aged 18 years or over, admitted between January 2015 and December 2020, who triggered a "Code Grey" response due to aggression or threatened/actual violence.

Main outcome measure

The primary outcome was prevalence of Code Grey events. Secondary outcomes included unadjusted and adjusted (logistic mixed model) effects of patient demographics, diagnoses and severity of illness on Code Grey events.

Results

There were 16175 ICU admissions relating to 14085 patients and 807 Code Grey events involving 379 (2.7%) patients. The observed count of events increased progressively from 2015 (n = 77) to 2020 (n = 204). For patients with a Code Grey, the median count of events was 3 (range 1-33). Independent predictors of at least one ICU Code Grey event included male sex (OR 2.5; 95% CI 1.8 to 3.4), young age (most elevated odds ratio in patients 20-30 years), admission from the emergency department (OR 2.8, 95% CI 2.1 to 3.6) and a trauma diagnosis (OR 1.4, 95% CI 1.1 to 1.9). Code Grey patients had longer admissions with a reduced risk of death.

Conclusions

The prevalence of Code Grey events in ICU appears to be increasing. Patients may have repeated events. Younger male patients admitted to ICU via the emergency department with a trauma or medical diagnosis are at greatest risk of a Code Grey event.

Study protocol and statistical analysis plan for the 20% Human Albumin Solution Fluid Bolus Administration Therapy in Patients after Cardiac Surgery-ll (HAS FLAIR-II) trial

Background: Fluid bolus therapy with 20% albumin may shorten the duration of vasopressor therapy in patients after cardiac surgery. Objective: To describe the study protocol and statistical analysis plan for the 20% Human Albumin Solution Fluid Bolus Administration Therapy in Patients after Cardiac Surgery-II (HAS FLAIR-II) trial. Design, setting, participants and intervention: HAS FLAIR-II is a phase 2b, multicentre, parallel group, openlabel, randomised controlled trial that will be conducted at six Australian intensive care units. Patients requiring fluid bolus therapy after cardiac surgery will be randomly assigned in a 1:1 ratio to the intervention of fluid bolus therapy with 20% albumin or a comparator of fluid bolus therapy with a crystalloid solution. Main outcome measures: The primary outcome measure is the cumulative duration of vasopressor therapy. Secondary outcomes include vasopressor use, service utilisation, and mortality. All analyses will be conducted on an intention-to-treat basis. Results and conclusion: The study protocol and statistical analysis plan will guide the conduct and analysis of the HAS FLAIR-II trial, such that analytical and reporting biases are minimised. Trial registration: This trial has been registered with the Australian New Zealand Clinical Trials Registry (ACTRN No. 12620000137998).

Early Active Mobilization during Mechanical Ventilation in the ICU

BACKGROUND

Intensive care unit (ICU)-acquired weakness often develops in patients who are undergoing invasive mechanical ventilation. Early active mobilization may mitigate ICU-acquired weakness, increase survival, and reduce disability.

METHODS

We randomly assigned 750 adult patients in the ICU who were undergoing invasive mechanical ventilation to receive increased early mobilization (sedation minimization and daily physiotherapy) or usual care (the level of mobilization that was normally provided in each ICU). The primary outcome was the number of days that the patients were alive and out of the hospital at 180 days after randomization.

RESULTS

The median number of days that patients were alive and out of the hospital was 143 (interquartile range, 21 to 161) in the early-mobilization group and 145 days (interquartile range, 51 to 164) in the usual-care group (absolute difference, -2.0 days; 95% confidence interval [CI], -10 to 6; P = 0.62). The mean (±SD) daily duration of active mobilization was 20.8±14.6 minutes and 8.8±9.0 minutes in the two groups, respectively (difference, 12.0 minutes per day; 95% CI, 10.4 to 13.6). A total of 77% of the patients in both groups were able to stand by a median interval of 3 days and 5 days, respectively (difference, -2 days; 95% CI, -3.4 to -0.6). By day 180, death had occurred in 22.5% of the patients in the early-mobilization group and in 19.5% of those in the usual-care group (odds ratio, 1.15; 95% CI, 0.81 to 1.65). Among survivors, quality of life, activities of daily living, disability, cognitive function, and psychological function were similar in the two groups. Serious adverse events were reported in 7 patients in the early-mobilization group and in 1 patient in the usual-care group. Adverse events that were potentially due to mobilization (arrhythmias, altered blood pressure, and desaturation) were reported in 34 of 371 patients (9.2%) in the early-mobilization group and in 15 of 370 patients (4.1%) in the usual-care group (P = 0.005).

CONCLUSIONS

Among adults undergoing mechanical ventilation in the ICU, an increase in early active mobilization did not result in a significantly greater number of days that patients were alive and out of the hospital than did the usual level of mobilization in the ICU. The intervention was associated with increased adverse events. (Funded by the National Health and Medical Research Council of Australia and the Health Research Council of New Zealand; TEAM ClinicalTrials.gov number, NCT03133377.).

Communication with bereaved family members after death in the ICU: the CATHARTIC randomised clinical trial

Objective: It is uncertain whether psychological distress in the family members of patients who die during an intensive care unit (ICU) admission may be improved by bereavement interventions. In this trial, relatives' symptoms of anxiety and depression after 6 months were measured when allocated to three commonly used bereavement follow-up strategies. Design: Single-centre, randomised, three parallel-group trial. Setting: A tertiary ICU in Australia. Participants: Relatives of patients who died in the ICU. Interventions: Relatives received bereavement follow-up 4 weeks after the death using a condolence letter, short telephone call or no contact. Main outcome measures: The primary outcome was the total Hospital Anxiety and Depression Scale (HADS-T) score. Secondary outcomes estimated anxiety, depression, complicated grief, post-traumatic stress, and satisfaction with ICU care. Results: Seventy-one relatives participated (24 had no contact, 19 were contacted by letter and 28 by telephone 4 weeks after the death). The mean HADS-T score for no contact was 16.1 (95% CI, 12.4-19.8). Receipt of a letter was associated with a mean HADS-T increase of 1.4 (4.0 decrease to 6.8 increase), and a condolence call was accompanied by a mean decrease of 1.6 (6.6 decrease to 3.4 increase; P > 0.5). Non-significant differences were observed for all secondary outcomes. Conclusions: Anxiety and depression at 6 months in the relatives of patients who died in the ICU was not meaningfully alleviated by receipt of either a condolence letter or telephone call. Trial registration: Australia New Zealand Clinical Trials Registry (ACTRN12619000917134).

β-Hydroxy-β-methylbutyrate (HMB) supplementation and functional outcomes in multi-trauma patients: a study protocol for a pilot randomised clinical trial (BOOST trial)

Background

There are no therapies proven to diminish the muscle wasting that occurs in patients after major trauma who are admitted to the intensive care unit (ICU). β-Hydroxy-β-methylbutyrate (HMB) is a nutrition intervention that may attenuate muscle loss and, thereby, improve recovery. The primary aim of this study is to determine the feasibility of a blinded randomised clinical trial of HMB supplementation to patients after major trauma who are admitted to the ICU. Secondary aims are to establish estimates for the impact of HMB when compared to placebo on muscle mass and nutrition-related patient outcomes.

Methods

This prospective, single-centre, blinded, randomised, placebo-controlled, parallel-group, feasibility trial with allocation concealment will recruit 50 participants over 18 months. After informed consent, participants will be randomised [1:1] to receive either the intervention (three grams of HMB dissolved in either 150 ml of orange juice for those allowed oral intake or 150 ml of water for those being enterally fed) or placebo (150 ml of orange juice for those allowed oral intake or 150 ml of water for those being enterally fed). The intervention will be commenced in ICU, continued after ICU discharge and ceased at hospital discharge or day 28 post randomisation, whichever occurs first. The primary outcome is the feasibility of administering the intervention. Secondary outcomes include change in muscle thickness using ultrasound and other nutritional and patient-centred outcomes.

Discussion

This study aims to determine the feasibility of administering HMB to critically ill multi-trauma patients throughout ICU admission until hospital discharge. Results will inform design of a larger randomised clinical trial.

Trial registration

The protocol is registered with Australian New Zealand Clinical Trials Registry (ANZCTR) ANZCTR: 12620001305910. UTN: U1111-1259-5534.

Protocol and statistical analysis plan for the phase 3 randomised controlled Treatment of Invasively Ventilated Adults with Early Activity and Mobilisation (TEAM III) trial

Objective: To describe the protocol and statistical analysis plan for the Treatment of Invasively Ventilated Adults with Early Activity and Mobilisation (TEAM III) trial. Design: An international, multicentre, parallel-group, randomised controlled phase 3 trial. Setting: Intensive care units (ICUs) in Australia, New Zealand, Germany, Ireland, the United Kingdom and Brazil. Patients: 750 adult patients expected to receive mechanical ventilation for more than 48 hours. Interventions: Early activity and mobilisation delivered to critically ill patients in an ICU for up to 28 days compared with standard care. Main outcome measures: The primary outcome is the number of days alive and out of hospital at 180 days after randomisation. Secondary outcomes include ICU-free days, ventilator-free days, delirium-free days, all-cause mortality at 28 and 180 days after randomisation, and functional outcome at 180 days after randomisation. Results: Recruitment at 46 research sites passed 576 patients in March 2021. Final collection of all 180-day outcome data for the target of 750 patients is anticipated by May 2022. Conclusions: Consistent with international guidelines, a detailed protocol and prospective analysis plan has been developed for the TEAM III trial. This plan specifies the statistical models for evaluating primary and secondary outcomes, defines covariates for adjusted analyses, and defines methods for exploratory analyses. Application of this protocol and statistical analysis plan to the forthcoming TEAM III trial will facilitate unbiased analyses of the clinical data collected. Trial registration:ClinicalTrials.gov identifier NCT03133377.

Administration of pharmacological sleep aids prior to, during and following critical illness

BACKGROUND

Sleep in the intensive care unit (ICU) is frequently disturbed and this may have a detrimental effect on recovery.

AIMS

To determine use of pharmacological sleep aids in critically ill patients prior to, during and after ICU admission.

METHODS

We conducted a single-centre period prevalence study of all adult patients admitted to a university-associated adult medical-surgical Intensive Care Unit (ICU) for more than two nights in a three-month period ending September 2019. The major outcome of interest was the proportion of ICU patients who had a pharmacological sleep aid administered prior to, during and after ICU admission. Associations of selected patient variables with sleep aid prescription in the ICU were summarized both as unadjusted univariable comparisons, and as adjusted effect estimates returned by a multivariable logistic regression model.

RESULTS

During the study period, 370 patients met all eligibility criteria. A pharmacological sleep aid was identified prior to hospital admission in 34 patients (9%) and in 62 patients (17%) during ICU admission. Of the 340 ICU survivors, 292 remained in the same hospital. Of these, 96 (33%) received a pharmacological sleep aid at least once during their post-ICU general hospital ward stay. Pre-hospital sleep aid use, male sex, longer ICU admission and higher APACHE III scores were associated with sleep aid prescription in the ICU.

CONCLUSIONS

Pharmacological sleep aids are administered frequently in the ICU with administration increasing substantially after ICU discharge. This article is protected by copyright. All rights reserved.

A microcosting analysis of ICU expenditure in the interval between brain death and organ donation

Objective: The cost of providing care in an intensive care unit (ICU) after brain death to facilitate organ donation is unknown. The objective of this study was to estimate expenditure for the care delivered in the ICU between the diagnosis of brain death and subsequent organ donation. Design: Cohort study of direct and indirect costs using bottom-up and top-down microcosting techniques. Setting: Single adult ICU in Australia. Participants: All patients who met criteria for brain death and proceeded to organ donation during a 13-month period between 1 January 2018 and 31 January 2019. Main outcome measures: A comprehensive cost estimate for care provided in the ICU from determination of brain death to transfer to theatre for organ donation. Results: Forty-five patients with brain death became organ donors during the study period. The mean duration of postdeath care in the ICU was 37.9 hours (standard deviation [SD], 16.5) at a mean total cost of $7520 (SD, $3136) per donor. ICU staff salaries were the greatest contributor to total costs, accounting for a median proportion of 0.72 of total expenditure (interquartile range, 0.68-0.75). Conclusions: Substantial costs are incurred in ICU for the provision of patient care in the interval between brain death and organ donation.

ICU trainee perception of end of life care provided during medical emergency team activation events

BACKGROUND

Hospital Medical Emergency Team (MET) activation events involving end of life care (EOLC) are common. The issues faced by medical staff attending these events are incompletely described.

METHODS

We conducted an anonymous, voluntary, internet-based survey of registered trainees of the College of Intensive Care Medicine of Australia and New Zealand in May 2019. The participants eligible were those trainees working in an adult intensive care unit in Victoria, Australia during the study period. The main outcome measures were self-reported levels of confidence, barriers to communication, frequency of conflict and distress, senior support, supervision and access to training.

RESULTS

Of 124 trainees surveyed, 75 (60%) responded. Overall, 78 % of respondents felt confident to manage EOLC MET calls, but the frequently reported barriers to effective patient / next of kin communication included 1) lack of private meeting rooms, 2) resource and time constraints and 3) lack of patient and family availability during a MET call to discuss medical treatment limitations. Two thirds of respondents reported emotional distress at least occasionally, this being frequent in one in five. Most trainees (68%) experienced conflict with other medical teams at least occasionally. Factors associated with experiencing distress at least occasionally include greater trainee age, patients' being unable to participate in discussion due to illness, resource and time constraints and negative encounters with other medical teams.

CONCLUSIONS

Victorian intensive care trainees were confident managing EOLC MET activation events. However, distress was reported commonly and strategies are required to address the areas of concern. This article is protected by copyright. All rights reserved.

Quantifying Response to Nutrition Therapy During Critical Illness: Implications for Clinical Practice and Research? A Narrative Review

Critical illness causes substantial muscle loss that adversely impacts recovery and health-related quality of life. Treatments are therefore needed that reduce mortality and/or improve the quality of survivorship. The purpose of this Review is to describe both patient-centered and surrogate outcomes that quantify responses to nutrition therapy in critically ill patients. The use of these outcomes in randomized clinical trials will be described and the strengths and limitations of these outcomes detailed. Outcomes used to quantify the response of nutrition therapy must have a plausible mechanistic relationship to nutrition therapy and either be an accepted measure for the quality of survivorship or highly likely to lead to improvements in survivorship. This Review identified that previous trials have utilized diverse outcomes. The variety of outcomes observed is probably due to a lack of consensus as to the most appropriate surrogate outcomes to quantify response to nutrition therapy during research or clinical practice. Recent studies have used, with some success, measures of muscle mass to evaluate and monitor nutrition interventions administered to critically ill patients.

Faecal diversion system usage in an adult intensive care unit

OBJECTIVE

To determine the frequency, indications and complications associated with the use of faecal diversion systems (rectal tubes) in critically ill patients.

DESIGN

A single centre observational study over 15 months.

SETTING

Intensive care unit (ICU).

PARTICIPANTS

Patients admitted during this period.

MAIN OUTCOME MEASURES

Frequency of rectal tubes utilisation in ICU, as well as associated adverse events, with major events defined as lower gastrointestinal bleeding associated with defined blood transfusion of two or more units of red cells or endoscopy or surgical intervention.

RESULTS

Of 3418 admission episodes, there were 111 episodes of rectal tubes inserted in 99 patients. Rectal tubes remained indwelling for a median of 5 days (range, 1-23) for a total of 641 patient-days. The most frequent indication for insertion was excessive bowel motions. A major adverse event was observed in three patients (3%; 0.5 events per 100 device days). Two patients underwent laparotomy and one patient sigmoidoscopy. These patients received between two and 23 units of packed red blood cells. Patients who had a rectal tube inserted had a substantially greater duration of ICU admission (mean, 14 days [SD, 14] v 2.8 days [SD, 3.7]) and hospital mortality (15% v 7.7%; risk ratio, 2.0; 95% CI, 1.2-3.4) as well as an overall higher Australian and New Zealand Risk of Death (ANZROD) score (mean, 27 [SD, 22] v 12.6 [SD, 20]).

CONCLUSION

Rectal tubes appear to be frequently inserted and can lead to major adverse events in critically ill patients.

Faecal diversion system usage in an adult intensive care unit

OBJECTIVE: To determine the frequency, indications and complications associated with the use of faecal diversion systems (rectal tubes) in critically ill patients. DESIGN: A single centre observational study over 15 months. SETTING: Intensive care unit (ICU). PARTICIPANTS: Patients admitted during this period. MAIN OUTCOME MEASURES: Frequency of rectal tubes utilisation in ICU, as well as associated adverse events, with major events defined as lower gastrointestinal bleeding associated with defined blood transfusion of two or more units of red cells or endoscopy or surgical intervention. RESULTS: Of 3418 admission episodes, there were 111 episodes of rectal tubes inserted in 99 patients. Rectal tubes remained indwelling for a median of 5 days (range, 1–23) for a total of 641 patient-days. The most frequent indication for insertion was excessive bowel motions. A major adverse event was observed in three patients (3%; 0.5 events per 100 device days). Two patients underwent laparotomy and one patient sigmoidoscopy. These patients received between two and 23 units of packed red blood cells. Patients who had a rectal tube inserted had a substantially greater duration of ICU admission (mean, 14 days [SD, 14] v 2.8 days [SD, 3.7]) and hospital mortality (15% v 7.7%; risk ratio, 2.0; 95% CI, 1.2–3.4) as well as an overall higher Australian and New Zealand Risk of Death (ANZROD) score (mean, 27 [SD, 22] v 12.6 [SD, 20]). CONCLUSION: Rectal tubes appear to be frequently inserted and can lead to major adverse events in critically ill patients.

Outcomes Six Months after Delivering 100% or 70% of Enteral Calorie Requirements during Critical Illness (TARGET). A Randomized Controlled Trial

Rationale: The long-term effects of delivering approximately 100% of recommended calorie intake via the enteral route during critical illness compared with a lesser amount of calories are unknown.Objectives: Our hypotheses were that achieving approximately 100% of recommended calorie intake during critical illness would increase quality-of-life scores, return to work, and key life activities and reduce death and disability 6 months later.Methods: We conducted a multicenter, blinded, parallel group, randomized clinical trial, with 3,957 mechanically ventilated critically ill adults allocated to energy-dense (1.5 kcal/ml) or routine (1.0 kcal/ml) enteral nutrition.Measurements and Main Results: Participants assigned energy-dense nutrition received more calories (percent recommended energy intake, mean [SD]; energy-dense: 103% [28] vs. usual: 69% [18]). Mortality at Day 180 was similar (560/1,895 [29.6%] vs. 539/1,920 [28.1%]; relative risk 1.05 [95% confidence interval, 0.95-1.16]). At a median (interquartile range) of 185 (182-193) days after randomization, 2,492 survivors were surveyed and reported similar quality of life (EuroQol five dimensions five-level quality-of-life questionnaire visual analog scale, median [interquartile range]: 75 [60-85]; group difference: 0 [95% confidence interval, 0-0]). Similar numbers of participants returned to work with no difference in hours worked or effectiveness at work (n = 818). There was no observed difference in disability (n = 1,208) or participation in key life activities (n = 705).Conclusions: The delivery of approximately 100% compared with 70% of recommended calorie intake during critical illness does not improve quality of life or functional outcomes or increase the number of survivors 6 months later.

Measuring nutrition-related outcomes in a cohort of multi-trauma patients following intensive care unit discharge

BACKGROUND

Functional recovery is an important outcome for those who survive critical illness. The present study aimed to assess nutrition provision and nutrition-related outcomes in a multi-trauma cohort following intensive care unit (ICU) discharge.

METHODS

The present study investigated a prospective cohort of patients discharged from an ICU, who had been admitted because of major trauma and required mechanical ventilation for at least 48 h. Nutrition-related outcomes, including body weight, quadriceps muscle layer thickness (QMLT), handgrip strength and subjective global assessment, were recorded on ICU discharge, days 5-7 post-ICU discharge and then weekly until hospital discharge. Nutrition intake was recorded for 5 days post-ICU discharge. Unless otherwise stated, data are presented as the mean (SD).

RESULTS

Twenty-eight patients [75% males, 55 (22.5) years] were included. Intake met 64% (28%) of estimated energy and 72% (32%) of protein requirements over the 5 days post-ICU discharge, which was similar to over the ICU admission. From ICU admission to hospital discharge, the mean reduction in weight was 4.2 kg (95% confidence interval = 2.2-6.3, P < 0.001) and after ICU discharge, the mean reduction in weight and QMLT was 2.6 kg (95% confidence interval = 1.0-4.2, P = 0.004) and 0.23 cm (95% confidence interval = 0.06-0.4, P = 0.01), respectively.

CONCLUSIONS

Patients received less energy and protein than estimated requirements after ICU discharge. Weight loss and reduction in QMLT also occurred during this period.

Systematic Review With Meta-Analysis of Patient-Centered Outcomes, Comparing International Guideline-Recommended Enteral Protein Delivery With Usual Care

BACKGROUND

International guidelines recommend that protein be administered enterally to critically ill patients at doses between 1.2 and 2 g/kg per day Observational data indicate that patients frequently receive less protein. The aim of this systematic review was to evaluate patient-centered outcomes with guideline-recommended enteral protein compared with usual care.

METHODS

A systematic review was performed of randomized controlled trials including critically ill adult patients provided predominately enteral nutrition with mean protein at ≥1.2 g/kg per day (intervention) and <1.2 g/kg per day (comparator). Random-effects models were applied for outcomes reported in ≥3 trials.

RESULTS

Of 1375 abstracts, 69 full-text articles were reviewed, and 6 trials meet the inclusion criteria, including 511 patients. The intervention group received a mean (SD) of 1.3 (0.08) g/kg per day, and the comparator group received 0.75 (0.15) g/kg per day protein. Insufficient data were available for meta-analyses on the primary outcome (muscle mass or strength). According to our meta-analyses, mortality at 28 days (5 studies) (risk ratio 0.92 [95% Cl 0.63-1.35], P = .66) and the durations of intensive care unit (6 studies) and hospital admission (4 studies) were similar between the intervention and comparator, with some uncertainty due to sample sizes and heterogeneity.

CONCLUSION

There are insufficient data to conclude whether protein provision within the current international guideline recommendations improves outcomes. In a limited dataset, enteral protein intakes near the lower level of current recommendations do not appear to reduce admission duration or mortality when compared with usual care in critically ill.

The Prognostic Value of the Diastolic Stress Test in Patients Undergoing Treadmill Stress Echocardiography

BACKGROUND

Exercise stress echocardiography (SE) is well validated for the evaluation of myocardial ischemia. Diastolic stress testing (DST) is recommended in the 2016 American Society of Echocardiography and European Association of Cardiovascular Imaging Guidelines for unexplained dyspnea. This study's aim was to prognostically evaluate the DST prospectively in a large stress testing population.

METHODS

Patients underwent SE with mitral E/e' measured before and after maximal treadmill exertion to estimate diastolic function. Patients were divided into four groups: group 1 (n = 201)-ischemic; group 2 (n = 1,563)-negative DST (E/e'_pre < 12, E/e'_post < 12); group 3 (n = 68)-positive DST (E/e'_pre < 12, E/e'_post ≥ 12); group 4 (n = 314)-high baseline E/e' (E/e'_pre ≥ 12).

RESULTS

Consecutive patients (n = 2,201, 770 [35%] female; 58 ± 12 years) were followed after SE for 27,964 patient-months. Time to first heart failure event (composite of heart failure admission, worsening New York Heart Association class, worsening ejection fraction, or cardiovascular death) was analyzed and adjusted using Cox proportional hazards regression. Ischemic patients hazard ratio (HR) was 28, 95% CI, 17-44, P < .0005, for subsequent heart failure compared with negative DST patients. Nonischemic, positive DSTs were highly predictive (HR = 4.2; 95% CI, 1.6-11.0; P = .001); while high E/e'_pre was not predictive (HR = 1.3; 95% CI, 0.7-2.4; P = .49) of future heart failure events.

CONCLUSIONS

DST differentiates heart failure prognosis in patients with induced diastolic dysfunction. Ischemia predictably portends the worst heart failure outcomes, and nonischemic, positive diastolic stress tests predicted more events compared with negative tests. These prognostic data support and add to the recommendations of the 2016 guidelines.

The effect of a low carbohydrate formula on glycaemia in critically ill enterally-fed adult patients with hyperglycaemia: A blinded randomised feasibility trial

BACKGROUND

Enteral nutrition is a source of carbohydrate that may exacerbate hyperglycaemia. Its treatment, insulin, potentially exacerbates glycaemic variability.

METHODS

This was a prospective, parallel group, blinded, randomised feasibility trial. Patients were eligible if 18 years or over when admitted to the intensive care unit and receiving enteral nutrition (EN) exclusively with two consecutive blood glucose > 10 mmol/L. A standardized glucose management protocol determined administration of insulin. Key outcome measures were insulin administered and glycaemic variability (coefficient of variation) over the first 48 h.

RESULTS

41 patients were randomized to either standard EN (14.1 g/100 mL carbohydrate; n = 20) or intervention EN (7.4 g/100 mL carbohydrate; n = 21). Overall 59% were male, mean (±SD) age of 62.3 years ± 10.4, APACHE II score of 16.5 ± 7.8 and a median (IQR) Body Mass Index 29.0 kg/m² (25.2-35.5). Most patients (73%) were mechanically ventilated. Approximately half (51%) were identified as having diabetes prior to ICU admission. Patients in the intervention arm received less insulin over the 48 h study period than those in the control group (mean insulin units over study period (95% CI) 45.0 (24.4-68.7) vs. 107 (56.1-157.9) units; p = 0.02) and had lower mean glycaemic variability (12.6 vs. 15.9%, p = 0.01). There was a small difference in the mean percentage of energy requirements met (intervention: 72.9 vs. control: 79.1%; p = 0.4) or protein delivered (78.2 vs. 85.4%; p = 0.3).

CONCLUSIONS

A low carbohydrate formula was associated with reduced insulin use and glycaemic variability in enterally-fed critically ill patients with hyperglycaemia. Further large trials are required to determine the impact of this formula on clinical outcomes. Registered under Australian and New Zealand Clinical Trials Registry, ANZCTR number: 12614000166673.

Antibiotic Prescribing in Response to Bacterial Isolates in the Intensive Care Unit

This study aimed to identify potential knowledge-performance gaps in antibiotic prescribing for bacterial isolates in the Intensive Care Unit (ICU) in order to guide the development of interventions such as antibiotic policies, decision support, and improved systems for communication between the laboratory and the bedside. A prospective observational cohort study of all patients admitted to a mixed medical/surgical ICU was undertaken over a six-month period in an Australian adult tertiary hospital. From a cohort of 524 patients, 108 had 303 isolates that were eligible for inclusion. Overall, 14.3% and 30.8% of sterile and non-sterile isolates respectively were associated with inadequate initial antibiotic therapy after identification of the bacteria. After sensitivity results were available inadequate directed therapy was observed in 4.0% and 21.3% of sterile and non-sterile isolates respectively. Problems were most commonly associated with isolates of Pseudomonas spp., Stenotrophomonas spp., Acinetobacter spp., S. aureus, enterococci and group III Enterobacteriaceae. Inadequate antibiotic therapy was found to be independently associated with prolonged length of ICU stay. Narrower spectrum antibiotic therapy was potentially available for 30% of isolates after sensitivity results were known. We conclude that there is scope to improve antibiotic prescribing in the ICU by providing clinicians with access to information regarding local susceptibility patterns and intrinsic resistance of bacteria, and spectra of antibiotic cover. Timely notification of laboratory results at the point of care may also facilitate improved prescribing performance.

The Influence of a Blood Conserving Device on Anaemia in Intensive Care Patients

The contribution of iatrogenic blood loss through diagnostic testing to the anaemia of critical illness remains controversial. We measured the effect of an arterial line blood conservation device upon blood loss and anaemia in adult intensive care patients.

This randomized controlled trial of 160 patients in a major Intensive Care Unit (ICU) compared a blood conservation device (Venous Arterial Blood Management Protection Plus, VAMP Plus system, Baxter Healthcare) (VAMP group) to a standard arterial pressure line set attached to an arterial catheter (control group). The primary outcome measured was the change in haemoglobin concentration (Hb) during each patient's ICU admission and the volume of blood lost through diagnostic testing in ICU was also recorded.

Both groups of 80 patients were matched for age, gender, severity of illness (APACHE II), baseline Hb on entry and ICU length of stay. Both groups had a similar (median [range]) change in Hb during ICU admission (VAMP-7 [- 84 to+21] g/l; Control -4 [-67 to+40] g/l; P=0.33). The VAMP patients lost significantly less blood for diagnostic testing while in ICU (VAMP 63 [0 to 787] ml; Control 133 [7 to 1227] ml; P=0.001).

We conclude that the VAMP Plus system significantly reduced iatrogenic blood loss in critically ill patients, but this reduction did not affect the fall in Hb that accompanies critical illness.

Blood Usage in an Australian Intensive Care Unit: Have We Met Best Practice Goals?

The transfusion of blood products, especially red cell concentrates, in critically ill patients is controversial and benefits of red cell concentrate transfusion in these patients have not been clearly demonstrated.

We performed a prospective observational study to compare best evidence to actual practice of red cell concentrate and other blood product administration in an intensive care unit (ICU) in a university-associated tertiary hospital. All primary admissions during a 28-day period were included in the study and data collected included transfusion of red cells and blood products, patient demographics and ICU and hospital outcome.

One hundred and seventy-five admissions were studied; 44% followed cardiac surgery. Forty-one patients (23%) received red cell concentrates in ICU, with 120 units transfused in 61 separate episodes. Other blood product usage was minimal. One third (20/61) of red cell concentrate transfusion episodes were of a single unit. The mean (±SD) pre-transfusion haemoglobin was 7.9±1.1 g/dl. Despite transfusion, such patients left ICU with a lower haemoglobin concentration compared with untransfused ICU patients (9.5±1.0 versus 10.5±2.1 g/dl; P<0.001). Cardiac surgical patients received similar red cell transfusion to general ICU patients. Univariate analysis showed no significant difference in mortality between patients who did or did not receive red cell concentrate transfusion (P=0.17). However, red cell concentrate transfusion was associated with a reduced adjusted mortality both in ICU (OR 0.13, 95% CI 0.02-0.73) and in hospital at 28 days (OR 0.10, 95% CI 0.02-0.58). The low red cell concentrate and blood product usage in our ICU were consistent with restrictive transfusion practice and selective red cell concentrate transfusion was associated with reduced mortality.

Effect of Early Sustained Prophylactic Hypothermia on Neurologic Outcomes Among Patients With Severe Traumatic Brain Injury: The POLAR Randomized Clinical Trial

IMPORTANCE

After severe traumatic brain injury, induction of prophylactic hypothermia has been suggested to be neuroprotective and improve long-term neurologic outcomes.

OBJECTIVE

To determine the effectiveness of early prophylactic hypothermia compared with normothermic management of patients after severe traumatic brain injury.

DESIGN, SETTING, AND PARTICIPANTS

The Prophylactic Hypothermia Trial to Lessen Traumatic Brain Injury-Randomized Clinical Trial (POLAR-RCT) was a multicenter randomized trial in 6 countries that recruited 511 patients both out-of-hospital and in emergency departments after severe traumatic brain injury. The first patient was enrolled on December 5, 2010, and the last on November 10, 2017. The final date of follow-up was May 15, 2018.

INTERVENTIONS

There were 266 patients randomized to the prophylactic hypothermia group and 245 to normothermic management. Prophylactic hypothermia targeted the early induction of hypothermia (33°C-35°C) for at least 72 hours and up to 7 days if intracranial pressures were elevated, followed by gradual rewarming. Normothermia targeted 37°C, using surface-cooling wraps when required. Temperature was managed in both groups for 7 days. All other care was at the discretion of the treating physician.

MAIN OUTCOMES AND MEASURES

The primary outcome was favorable neurologic outcomes or independent living (Glasgow Outcome Scale-Extended score, 5-8 [scale range, 1-8]) obtained by blinded assessors 6 months after injury.

RESULTS

Among 511 patients who were randomized, 500 provided ongoing consent (mean age, 34.5 years [SD, 13.4]; 402 men [80.2%]) and 466 completed the primary outcome evaluation. Hypothermia was initiated rapidly after injury (median, 1.8 hours [IQR, 1.0-2.7 hours]) and rewarming occurred slowly (median, 22.5 hours [IQR, 16-27 hours]). Favorable outcomes (Glasgow Outcome Scale-Extended score, 5-8) at 6 months occurred in 117 patients (48.8%) in the hypothermia group and 111 (49.1%) in the normothermia group (risk difference, 0.4% [95% CI, -9.4% to 8.7%]; relative risk with hypothermia, 0.99 [95% CI, 0.82-1.19]; P = .94). In the hypothermia and normothermia groups, the rates of pneumonia were 55.0% vs 51.3%, respectively, and rates of increased intracranial bleeding were 18.1% vs 15.4%, respectively.

CONCLUSIONS AND RELEVANCE

Among patients with severe traumatic brain injury, early prophylactic hypothermia compared with normothermia did not improve neurologic outcomes at 6 months. These findings do not support the use of early prophylactic hypothermia for patients with severe traumatic brain injury.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00987688; Anzctr.org.au Identifier: ACTRN12609000764235.

Diabetes-Specific Formulae Versus Standard Formulae as Enteral Nutrition to Treat Hyperglycemia in Critically Ill Patients: Protocol for a Randomized Controlled Feasibility Trial

Background

During critical illness, hyperglycemia is prevalent and is associated with adverse outcomes. While treating hyperglycemia with insulin reduces morbidity and mortality, it increases glycemic variability and hypoglycemia risk, both of which have been associated with an increase in mortality. Therefore, other interventions which improve glycemic control, without these complications should be explored. Nutrition forms part of standard care, but the carbohydrate load of these formulations has the potential to exacerbate hyperglycemia. Specific diabetic-formulae with a lesser proportion of carbohydrate are available, and these formulae are postulated to limit glycemic excursions and reduce patients’ requirements for exogenous insulin.

Objective

The primary outcome of this prospective, blinded, single center, randomized controlled trial is to determine whether a diabetes-specific formula reduces exogenous insulin administration. Key secondary outcomes include the feasibility of study processes as well as glycemic variability.

Methods

Critically ill patients will be eligible if insulin is administered whilst receiving exclusively liquid enteral nutrition. Participants will be randomized to receive a control formula, or a diabetes-specific, low glycemic index, low in carbohydrate study formula. Additionally, a third group of patients will receive a second diabetes-specific, low glycemic index study formula, as part of a sub-study to evaluate its effect on biomarkers. This intervention group (n=12) will form part of recruitment to a nested cohort study with blood and urine samples collected at randomization and 48 hours later for the first 12 participants in each group with a secondary objective of exploring the metabolic implications of a change in nutrition formula. Data on relevant medication and infusions, nutrition provision and glucose control will be collected to a maximum of 48 hours post randomization. Baseline patient characteristics and anthropometric measures will be recorded. A 28-day phone follow-up will explore weight and appetite changes as well as blood glucose control pre and post intensive care unit (ICU) discharge.

Results

Recruitment commenced in February 2015 with an estimated completion date for data collection by May 2018. Results are expected to be available late 2018.

Conclusions

This feasibility study of the effect of diabetes-specific formulae on the administration of insulin in critically ill patients and will inform the design of a larger, multi-center trial.

Trial Registration

Australian New Zealand Clinical Trial Registry (ANZCTR):12614000166673; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12614000166673 (Archived by WebCite at http://www.webcitation.org/6xs0phrVu)

Sodium reduction during cardiopulmonary bypass: Plasma-Lyte 148 versus trial fluid as pump primes

OBJECTIVES

We compared effects on plasma sodium concentrations plus calculated plasma tonicity of two "balanced" crystalloid solutions used as 2 L pump primes during cardiopulmonary bypass (CPB): Plasma-Lyte 148 (sodium concentration, 140 mmol/L; potassium concentration, 5 mmol/L) versus a bicarbonate-balanced fluid (sodium concentration, 140 mmol/L; potassium concentration, 0 mmol/L).

DESIGN, SETTING AND PARTICIPANTS

We analysed pooled data from two prospective interventional studies performed in university-affiliated hospitals, from 50 patients undergoing elective cardiac surgery.

INTERVENTIONS

Participants were allocated equally to Plasma-Lyte 148 or bicarbonate-balanced fluid, with plasma electrolytes measured by direct ion selective electrodes immediately before bypass (pre-CPB), within 3 minutes of commencement (T2), and before bypass cessation (end-CPB).

RESULTS

Plasma sodium fell at T2 in 46 patients (92%) (P<0.0005). With Plasma-Lyte 148, the mean sodium decreased by 3.0 mmol/L (SD, 1.7 mmol/L), and with bicarbonate-balanced fluid it decreased by 2.2 mmol/L (SD, 1.1 mmol/L) (P=0.002). The mean tonicity fell by >5 mOsm/kg for both groups (P<0.0005). At end-CPB, the mean sodium for both groups remained reduced by >2 mmol/L (P<0.0005). In the group receiving Plasma-Lyte 148, 52% of patients were hyponatraemic (sodium<135 mmol/L) at T2 and end-CPB.

CONCLUSIONS

Sodium reductions were common with both priming solutions, but more severe with Plasma-Lyte 148. Crystalloid priming solutions require sodium concentrations>140mmol/L to ensure normonatraemia throughout CPB.

Disagreement between ion selective electrode direct and indirect sodium measurements: estimation of the problem in a tertiary referral hospital

PURPOSE

We estimated the proportion of indirect ion selective electrode (ISE) plasma sodium analyses in intensive care unit (ICU) and hospital wide, exhibiting important disagreement with direct ISE results in relation to abnormal plasma protein concentrations.

MATERIALS AND METHODS

Direct and indirect ISE plasma sodium measurements were performed on 346 clinical specimens selected to reflect low, normal, or high total protein concentrations. Important intermethod disagreement was defined as |4| mmol/L or higher. Results were extrapolated to a 3-month laboratory series of 48,033 indirect ISE assays, including 2877 samples from intensive care.

RESULTS

Intermethod sodium disagreement at |4| mmol/L or higher was predicted for 25% of ICU samples. Almost all (97%) occurred in hypoproteinemic samples where indirect tended to exceed direct ISE estimates. Hospital wide, such disagreement was projected to occur in 8% of samples, of which the majority (70%) were also hypoproteinemic.

CONCLUSIONS

Important disagreement between indirect and direct ISE sodium measurements may exist in up to 1 in 4 ICU specimens and 1 in 12 hospital-wide samples. The main problem is indirect ISE overestimation associated with hypoproteinemia, potentially leading to misclassifications of pseudohypernatremia and pseudonormonatremia. We recommend that hospital laboratories consider standardization using direct ISE sodium measurement.

Plasma acetate, gluconate and interleukin-6 profiles during and after cardiopulmonary bypass: a comparison of Plasma-Lyte 148 with a bicarbonate-balanced solution

INTRODUCTION

As even small concentrations of acetate in the plasma result in pro-inflammatory and cardiotoxic effects, it has been removed from renal replacement fluids. However, Plasma-Lyte 148 (Plasma-Lyte), an electrolyte replacement solution containing acetate plus gluconate is a common circuit prime for cardio-pulmonary bypass (CPB). No published data exist on the peak plasma acetate and gluconate concentrations resulting from the use of Plasma-Lyte 148 during CPB.

METHODS

Thirty adult patients were systematically allocated 1:1 to CPB prime with either bicarbonate-balanced fluid (24 mmol/L bicarbonate) or Plasma-Lyte 148. Arterial blood acetate, gluconate and interleukin-6 (IL-6) levels were measured immediately before CPB (T1), three minutes after CPB commencement (T2), immediately before CPB separation (T3), and four hours post separation (T4).

RESULTS

Acetate concentrations (normal 0.04 to 0.07 mmol/L) became markedly elevated at T2, where the Plasma-Lyte group (median 3.69, range (2.46 to 8.55)) exceeded the bicarbonate group (0.16 (0.02 to 3.49), P < 0.0005). At T3, levels had declined but the differential pattern remained apparent (Plasma-Lyte 0.35 (0.00 to 1.84) versus bicarbonate 0.17 (0.00 to 0.81)). Normal circulating acetate concentrations were not restored until T4. Similar gluconate concentration profiles and inter-group differences were seen, with a slower T3 decay. IL-6 increased across CPB, peaking at T4, with no clear difference between groups.

CONCLUSIONS

Use of acetate containing prime solutions result in supraphysiological plasma concentrations of acetate. The use of acetate-free prime fluid in CPB significantly reduced but did not eliminate large acetate surges in cardiac surgical patients. Complete elimination of acetate surges would require the use of acetate free bolus fluids and cardioplegia solutions.

TRIAL REGISTRATION

Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12610000267055.

Venous thromboembolism prophylaxis in the critically ill: a point prevalence survey of current practice in Australian and New Zealand intensive care units

BACKGROUND

Critically ill patients are at high risk of morbidity and mortality caused by venous thromboembolism (VTE). In addition to premorbid predisposing conditions, critically ill patients may be exposed to prolonged immobility, invasive intravascular catheters and frequent operative procedures, and further may have contraindications to pharmaceutical prophylactic measures designed to attenuate VTE risk. There are limited data describing current VTE prophylaxis regimens in Australia and New Zealand.

OBJECTIVE

To document current Australian and New Zealand management of VTE prophylaxis in a large mixed cohort of critically ill patients.

DESIGN

Prospective, multicentre point prevalence survey endorsed by the Australian and New Zealand Intensive Care Society Clinical Trials Group (ANZICS CTG).

SETTING

30 public hospital ICUs in Australia and New Zealand surveyed on Wednesday 9 May 2007.

METHODS

For all patients in each ICU on the study day, demographic data, admission diagnosis and information on VTE prophylaxis were prospectively collected.

RESULTS

502 patients were included in the survey, and 431 of these (86%) received VTE prophylaxis. Of these, 64% (276/431) received pharmacological prophylaxis and 80% (345/431) received mechanical prophylaxis, with 44% (190/431) receiving both. Of those receiving pharmacological prophylaxis, unfractionated heparin was used in 74%, and enoxaparin (low molecular weight heparin) in 23%. Contraindications to pharmacological prophylaxis were reported in 122 patients. Overall, pharmacological prophylaxis was administered to 87% of potentially suitable patients.

CONCLUSIONS

We observed a high prevalence of VTE prophylaxis, with many critically ill patients receiving two or more modalities of prophylaxis. These results show that the potential risk of VTE in critically ill patients is recognised in Australia and New Zealand, and strategies to mitigate this serious complication are widely implemented.

A randomised, controlled trial of conventional versus automated weaning from mechanical ventilation using SmartCare/PS

OBJECTIVE

Preliminary assessment of an automated weaning system (SmartCare/PS) compared to usual management of weaning from mechanical ventilation performed in the absence of formal protocols.

DESIGN AND SETTING

A randomised, controlled pilot study in one Australian intensive care unit.

PATIENTS

A total of 102 patients were equally divided between SmartCare/PS and Control.

INTERVENTIONS

The automated system titrated pressure support, conducted a spontaneous breathing trial and provided notification of success ("separation potential").

MEASUREMENTS AND RESULTS

The median time from the first identified point of suitability for weaning commencement to the state of "separation potential" using SmartCare/PS was 20 h (interquartile range, IQR, 2-40) compared to 8 h (IQR 2-43) with Control (log-rank P = 0.3). The median time to successful extubation was 43 h (IQR 6-169) using SmartCare/PS and 40 (14-87) with Control (log-rank P = 0.6). Unadjusted, the estimated probability of reaching "separation potential" was 21% lower (95% CI, 48% lower to 20% greater) with SmartCare/PS compared to Control. Adjusted for other covariates (age, gender, APACHE II, SOFAmax, neuromuscular blockade, corticosteroids, coma and elevated blood glucose), these estimates were 31% lower (95% CI, 56% lower to 9% greater) with SmartCare/PS. The study groups showed comparable rates of reintubation, non-invasive ventilation post-extubation, tracheostomy, sedation, neuromuscular blockade and use of corticosteroids.

CONCLUSIONS

Substantial reductions in weaning duration previously demonstrated were not confirmed when the SmartCare/PS system was compared to weaning managed by experienced critical care specialty nurses, using a 1:1 nurse-to-patient ratio. The effect of SmartCare/PS may be influenced by the local clinical organisational context.

DESCRIPTOR

28. Mechanical ventilation: weaning.

Vasopressin versus norepinephrine infusion in patients with septic shock

BACKGROUND

Vasopressin is commonly used as an adjunct to catecholamines to support blood pressure in refractory septic shock, but its effect on mortality is unknown. We hypothesized that low-dose vasopressin as compared with norepinephrine would decrease mortality among patients with septic shock who were being treated with conventional (catecholamine) vasopressors.

METHODS

In this multicenter, randomized, double-blind trial, we assigned patients who had septic shock and were receiving a minimum of 5 microg of norepinephrine per minute to receive either low-dose vasopressin (0.01 to 0.03 U per minute) or norepinephrine (5 to 15 microg per minute) in addition to open-label vasopressors. All vasopressor infusions were titrated and tapered according to protocols to maintain a target blood pressure. The primary end point was the mortality rate 28 days after the start of infusions.

RESULTS

A total of 778 patients underwent randomization, were infused with the study drug (396 patients received vasopressin, and 382 norepinephrine), and were included in the analysis. There was no significant difference between the vasopressin and norepinephrine groups in the 28-day mortality rate (35.4% and 39.3%, respectively; P=0.26) or in 90-day mortality (43.9% and 49.6%, respectively; P=0.11). There were no significant differences in the overall rates of serious adverse events (10.3% and 10.5%, respectively; P=1.00). In the prospectively defined stratum of less severe septic shock, the mortality rate was lower in the vasopressin group than in the norepinephrine group at 28 days (26.5% vs. 35.7%, P=0.05); in the stratum of more severe septic shock, there was no significant difference in 28-day mortality (44.0% and 42.5%, respectively; P=0.76). A test for heterogeneity between these two study strata was not significant (P=0.10).

CONCLUSIONS

Low-dose vasopressin did not reduce mortality rates as compared with norepinephrine among patients with septic shock who were treated with catecholamine vasopressors. (Current Controlled Trials number, ISRCTN94845869 [controlled-trials.com].).

Decisions made by critical care nurses during mechanical ventilation and weaning in an Australian intensive care unit

BACKGROUND

Responsibilities of critical care nurses for management of mechanical ventilation may differ among countries. Organizational interventions, including weaning protocols, may have a variable impact in settings that differ in nursing autonomy and interdisciplinary collaboration.

OBJECTIVE

To characterize the role of Australian critical care nurses in the management of mechanical ventilation.

METHODS

A 3-month, prospective cohort study was performed. All clinical decisions related to mechanical ventilation in a 24-bed, combined medical-surgical adult intensive care unit at the Royal Melbourne Hospital, a university-affiliated teaching hospital in Melbourne, Victoria, Australia, were determined.

RESULTS

Of 474 patients admitted during the 81-day study period, 319 (67%) received mechanical ventilation. Death occurred in 12.5% (40/319) of patients. Median durations of mechanical ventilation and intensive care stay were 0.9 and 1.9 days, respectively. A total of 3986 ventilation and weaning decisions (defined as any adjustment to ventilator settings, including mode change; rate or pressure support adjustment; and titration of tidal volume, positive end-expiratory pressure, or fraction of inspired oxygen) were made. Of these, 2538 decisions (64%) were made by nurses alone, 693 (17%) by medical staff, and 755 (19%) by nurses and staff in collaboration. Decisions made exclusively by nurses were less common for patients with predominantly respiratory disease or multiple organ dysfunction than for other patients.

CONCLUSIONS

In this unit, critical care nurses have high levels of responsibility for, and autonomy in, the management of mechanical ventilation and weaning. Revalidation of protocols for ventilation practices in other clinical contexts may be needed.

Decisions Made By Critical Care Nurses During Mechanical Ventilation and Weaning in an Australian Intensive Care Unit

Background Responsibilities of critical care nurses for management of mechanical ventilation may differ among countries. Organizational interventions, including weaning protocols, may have a variable impact in settings that differ in nursing autonomy and interdisciplinary collaboration.

Objective To characterize the role of Australian critical care nurses in the management of mechanical ventilation.

Methods A 3-month, prospective cohort study was performed. All clinical decisions related to mechanical ventilation in a 24-bed, combined medical-surgical adult intensive care unit at the Royal Melbourne Hospital, a university-affiliated teaching hospital in Melbourne, Victoria, Australia, were determined.

Results Of 474 patients admitted during the 81-day study period, 319 (67%) received mechanical ventilation. Death occurred in 12.5% (40/319) of patients. Median durations of mechanical ventilation and intensive care stay were 0.9 and 1.9 days, respectively. A total of 3986 ventilation and weaning decisions (defined as any adjustment to ventilator settings, including mode change; rate or pressure support adjustment; and titration of tidal volume, positive end-expiratory pressure, or fraction of inspired oxygen) were made. Of these, 2538 decisions (64%) were made by nurses alone, 693 (17%) by medical staff, and 755 (19%) by nurses and staff in collaboration. Decisions made exclusively by nurses were less common for patients with predominantly respiratory disease or multiple organ dysfunction than for other patients.

Conclusions In this unit, critical care nurses have high levels of responsibility for, and autonomy in, the management of mechanical ventilation and weaning. Revalidation of protocols for ventilation practices in other clinical contexts may be needed.

Update in computer-driven weaning from mechanical ventilation

Weaning from mechanical ventilation is a complex process requiring assessment and interpretation of both objective and subjective clinical parameters. For many years, automated computerised systems for various medical processes, including respiratory management, have been proposed to optimise decision-making and reduce variation amongst clinicians. SmartCare/PS, available since 2003 as a software application for the EvitaXL ventilator (Dräger Medical AG & Co. KG, Lübeck, Germany), is one of the first such ventilator systems to be made commercially available. SmartCare/PS can be described as a knowledge-based weaning system, which adjusts pressure support based on measurement of the patient's respiratory status, specifically the spontaneous respiratory rate, tidal volume and end-tidal carbon dioxide with the aim of optimising the weaning process. The primary proposed advantage of this system is an ability to provide management of ventilatory weaning through continuous physiological monitoring and real-time interventions. The relatively small number of available clinical studies indicate the system is able to deliver appropriate ventilation during pressure support weaning from both short-term and prolonged ventilation. Of potential clinical note, a recent study suggested that use of SmartCare/PS might be associated with useful reductions in the duration of weaning compared to existing clinical practice using weaning protocols. One recently published randomised trial supports this conclusion. However, given the known large variation in international critical care ventilatory practices further randomised trials are desirable.

Reduction of broad-spectrum antibiotic use with computerized decision support in an intensive care unit

OBJECTIVE

To implement and evaluate the effect of a computerized decision support tool on antibiotic use in an intensive care unit (ICU).

DESIGN

Prospective before-and-after cohort study.

SETTING

Twenty-four bed tertiary hospital adult medical/surgical ICU.

PARTICIPANTS

All consecutive patients from May 2001 to November 2001 (N = 524) and March 2002 to September 2002 (N = 536).

INTERVENTION

A real-time microbiology browser and computerized decision support system for isolate directed antibiotic prescription.

MAIN OUTCOME MEASURES

Number of courses of antibiotic prescribed, antibiotic utilization (defined daily doses (DDDs)/100 ICU bed-days), antibiotic susceptibility mismatches, and system uptake.

RESULTS

There was a significant reduction in the proportion of patients prescribed carbapenems [odds ratio (OR) = 0.61, 95% confidence interval (CI) = 0.39-0.97, P = 0.04], third-generation cephalosporins (OR = 0.58, 95% CI = 0.42-0.79, P = 0.001), and vancomycin (OR = 0.67, 95% CI = 0.45-1.00, P = 0.05) after adjustment for risk factors including Apache II score, suspected infection, positive microbiology, intubation, and length of stay. The decision support tool was associated with a 10.5% reduction in both total antibiotic utilization (166-149 DDDs/100 ICU bed days) and the highest volume broad-spectrum antibiotics. There were fewer susceptibility mismatches for initial antibiotic therapy (OR = 0.63, 95% CI = 0.39-0.98, P = 0.02) and increased de-escalation to narrower spectrum antibiotics. Uptake of the program was high with 6028 access episodes during the 6-month evaluation period.

CONCLUSIONS

This tool streamlined collation and clinical use of microbiology results and integrated into the daily ICU workflow. Its introduction was accompanied by a reduction in both total and broad-spectrum antibiotic use and an increase in the number of switches to narrower spectrum antibiotics.

Epidemiology of sepsis in Victoria, Australia

OBJECTIVE

To determine the clinical and epidemiologic characteristics of patients with sepsis admitted to hospitals in Victoria, Australia, including the incidence of sepsis and severe sepsis, utilization of intensive care unit (ICU) resources, and hospital mortality.

DESIGN

A population-based hospital morbidity database generated from hospital discharge coding.

SETTING

State of Victoria, Australia (population, 4.5 million), the 4-yr period from July 1, 1999, to June 30, 2003.

PATIENTS

A total of 3,122,515 overnight hospitalizations.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The overall hospital incidence of sepsis was 1.1%, with a mortality of 18.4%. Of septic patients, 23.8% received some care in an ICU. For these patients, hospital mortality was 28.9%. Severe sepsis, defined by sepsis and at least one organ dysfunction, occurred in 39% of sepsis patients and was accompanied by a hospital mortality of 31.1%. Fifty percent of patients with severe sepsis received at least some care in an ICU.

CONCLUSIONS

Australian state hospital administrative data reveal epidemiologic features of sepsis and severe sepsis that are strikingly similar to those recently reported from comparable populations in North American and Europe. This suggests that lessons learned in this area may be directly applicable internationally.

Pulmonary alveolar proteinosis

Pulmonary alveolar proteinosis (PAP) has been recognized for almost half a century. At least three separate pathophysiologic mechanisms may lead to the characteristic feature of PAP: the excessive accumulation of surfactant lipoprotein in pulmonary alveoli, with associated disturbance of pulmonary gas exchange. The prognosis for adult patients with PAP varies, but disease-specific survival rate exceeds 80% at 5 years. The survival rates for adult PAP patients seem to have increased progressively in the four decades since the initial clinical description of this condition. The last decade has brought new advances in laboratory and clinical research that are lifting a veil not only on PAP but also on general aspects of pulmonary surfactant biology and innate immune defense.

Relationship of anti-GM-CSF antibody concentration, surfactant protein A and B levels, and serum LDH to pulmonary parameters and response to GM-CSF therapy in patients with idiopathic alveolar proteinosis

BACKGROUND

Conventional measures of the severity of alveolar proteinosis (AP) include alveolar-arterial oxygen gradient ([A - a]DO(2)), vital capacity (VC), and carbon monoxide transfer factor (TLCO), but alternative serological measures have been sought. Granulocyte-macrophage colony stimulating factor (GM-CSF) neutralising autoantibody is found in patients with idiopathic acquired AP. We have investigated the interrelationships between the levels of this antibody and those of surfactant protein (SP)-A and -B, lactate dehydrogenase (LDH), and conventional measures of disease severity, and the capacity of these parameters to predict the response to rhGM-CSF treatment.

METHODS

Blood levels of anti-GM-CSF antibodies, SP-A, SP-B, LDH, and [A - a]DO(2), VC, and TLCO were measured before rhGM-CSF treatment and every 2 weeks thereafter in 14 patients with AP.

RESULTS

At baseline, high levels of anti-GM-CSF antibodies and increased SP-A and SP-B levels were seen in all patients, and LDH was raised in 83%. SP-A was highly correlated with [A - a]DO(2), VC, and TLCO (p</=0.02), but other markers were not. Only a normal LDH level was predictive of a response to rhGM-CSF treatment (p=0.03). During treatment a correlation between conventional and serological variables within patients was seen only between SP-A and [A - a]DO(2) (p=0.054), LDH levels and [A - a]DO(2) (p=0.010), and LDH levels and VC (p=0.019).

CONCLUSIONS

Of the serological parameters studied, only SP-A and LDH levels were correlated with conventional measures of disease severity, with LDH most accurately reflecting [A - a]DO(2) and vital capacity. Only a normal LDH level predicted a higher likelihood of response to treatment with GM-CSF.

Outcome of patients admitted to the intensive care unit with newly diagnosed small cell lung cancer

Patients with newly diagnosed small cell lung cancer (SCLC) may be considered for admission to an intensive care unit (ICU). Even though SCLC is highly responsive to chemotherapy, it is not clear whether patient outcomes justify the resource use of an ICU. This paper reports the results of a retrospective review of 20 newly diagnosed cases of SCLC who were admitted to one of three ICUs in Melbourne, Australia. Patients who had more than one negative prognostic factor did uniformly poorly, with no survivors beyond 4 months. Five patients were treated with chemotherapy whilst intubated and receiving mechanical ventilatory support. Two of these patients responded to chemotherapy and were extubated 4 days later. Both of these patients were alive and free of tumour recurrence 7 months later. In contrast, patients not treated with chemotherapy died early (within 40 days). We conclude that some patients with SCLC achieve a medium to long-term survival following treatment with chemotherapy instituted during or around the time of their admission to an ICU. The admission to an ICU of selected patients with SCLC may be justified, and prognostic indicators may be of benefit in making these difficult treatment decisions.

Pulmonary alveolar proteinosis: progress in the first 44 years

Pulmonary alveolar proteinosis is a rare clinical syndrome that was first described in 1958. Subsequently, over 240 case reports and small series have described at least 410 cases in the literature. Characterized by the alveolar accumulation of surfactant components with minimal interstitial inflammation or fibrosis, pulmonary alveolar proteinosis has a variable clinical course ranging from spontaneous resolution to death with pneumonia or respiratory failure. The most effective proven treatment--whole lung lavage--was described soon after the first recognition of this disease. In the last 8 years, there has been rapid progress toward elucidation of the molecular mechanisms underlying both the congenital and acquired forms of pulmonary alveolar proteinosis, following serendipitous discoveries in gene-targeted mice lacking granulocyte-macrophage colony-stimulating factor (GM-CSF). Impairment of surfactant clearance by alveolar macrophages as a result of inhibition of the action of GM-CSF by blocking autoantibodies may underlie many acquired cases, whereas congenital disease is most commonly attributable to mutations in surfactant protein genes but may also be caused by GM-CSF receptor defects. Therapy with GM-CSF has shown promise in approximately half of those acquired cases treated, but it is unsuccessful in congenital forms of the disease, consistent with the known differences in disease pathogenesis.

A randomized phase II trial of granulocyte-macrophage colony-stimulating factor therapy in severe sepsis with respiratory dysfunction

Granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulates hemopoiesis and effector functions of granulocytes and macrophages and is involved in pulmonary surfactant homeostasis. We investigated whether GM-CSF therapy improved clinically diagnosed severe sepsis and respiratory dysfunction in critically ill patients. This randomized, double-blind, placebo-controlled phase II study added low-dose (3 mcg/kg) intravenous recombinant human GM-CSF daily for 5 days to conventional therapy in 10 patients, with a further eight patients receiving placebo. GM-CSF-treated patients showed improvement in Pa(O(2))/FI(O(2)) over 5 days (p = 0.02) and increased peripheral blood neutrophils (p = 0.08), whereas alveolar neutrophils decreased (p = 0.02). GM-CSF therapy was not associated with decreased 30-day survival or with increased acute respiratory distress syndrome or extrapulmonary organ dysfunction. GM-CSF therapy was associated with increased blood granulocyte superoxide production and restoration or preservation of blood and alveolar leukocyte phagocytic function. We conclude that low-dose GM-CSF was associated with improved gas exchange without pulmonary neutrophil infiltration, despite functional activation of both circulating neutrophils and pulmonary phagocytes. In addition, GM-CSF therapy was not associated with worsened acute respiratory distress syndrome or the multiple organ dysfunction syndrome, suggesting a homeostatic role for GM-CSF in sepsis-related pulmonary dysfunction.

Chest physiotherapy for the prevention of ventilator-associated pneumonia

OBJECTIVE

Pneumonia is an important complication in patients who are intubated and mechanically ventilated, when it is commonly referred to as ventilator-associated pneumonia (VAP). Since VAP may be contributed to by impaired sputum clearance, we studied whether chest physiotherapy designed to enhance sputum clearance decreases the occurrence of VAP.

DESIGN

Prospective controlled systematic allocation trial.

SETTING

Tertiary teaching hospital ICU.

PATIENTS AND PARTICIPANTS

Sixty adult patients intubated and mechanically ventilated for at least 48 h.

INTERVENTIONS

Chest physiotherapy (intervention group) or sham physiotherapy (control group).

MEASUREMENTS AND RESULTS

Control and intervention groups were well matched for age, sex, and admission PaO(2)/FiO(2) ratio, APACHE II score, and Glasgow Coma Score. There were no differences in the duration of mechanical ventilation, length of stay in ICU or mortality. VAP was assessed daily by combined clinical assessment and the clinical pulmonary infection score (CPIS). VAP occurred in 39% (14/36) of the control group and 8% (2/24) of the intervention group (OR = 0.14, 95% CI 0.03 to 0.56, P = 0.02). After adjustment was made by logistic regression for other important variables (APACHE II score, duration of mechanical ventilation, presence of tracheostomy, and GCS score), chest physiotherapy was independently associated with a reduced occurrence of VAP (adjusted OR = 0.16, 95% CI 0.03 to 0.94, P = 0.02).

CONCLUSIONS

In this small trial, chest physiotherapy in ventilated patients was independently associated with a reduction in VAP. This suggested benefit of physiotherapy in prevention of VAP requires confirmation with a larger randomised controlled trial.

Therapeutic efficacy of granulocyte-macrophage colony-stimulating factor in patients with idiopathic acquired alveolar proteinosis

Alveolar proteinosis (AP) is characterized by excessive surfactant accumulation, and most cases are of unknown etiology. Standard therapy for AP is whole-lung lavage, which may not correct the underlying defect. Because the hematopoietic cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF) is required for normal surfactant homeostasis, we evaluated the therapeutic activity of GM-CSF in patients with idiopathic AP. Fourteen patients received 5 microg/kg/d GM-CSF for 6 to 12 wk with serial monitoring of the alveolar-arterial oxygen gradient ([A-a]DO2), diffusing capacity of carbon monoxide, computed tomographic scans, and exercise testing. Patients not responding to 5 microg/kg/d GM-CSF underwent stepwise dose escalation, and responding patients were retreated at disease recurrence. Stored pretreatment sera were assayed for GM-CSF-neutralizing autoantibodies. According to prospective criteria, five of 14 patients responded to 5 microg/kg/d GM- CSF, and one of four patients responded after dose escalation (20 microg/kg/d). The overall response rate was 43% (mean improvement in [A-a]DO2 = 23.2 mm Hg). Responses lasted a median of 39 wk, and were reproducible with retreatment. GM-CSF was well-tolerated, with no late toxicity seen. The only treatment-related factor predictive of response was GM-CSF-induced eosinophilia (p = 0.01). Each of 12 patients tested had GM-CSF-neutralizing autoantibodies present in pretreatment serum. We conclude that GM- CSF has therapeutic activity in idiopathic AP, providing a potential alternative to whole-lung lavage.

Plasma granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor levels in critical illness including sepsis and septic shock: relation to disease severity, multiple organ dysfunction, and mortality

OBJECTIVE

To define the circulating levels of granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) during critical illness and to determine their relationship to the severity of illness as measured by the Acute Physiology and Chronic Health Evaluation (APACHE) II score, the development of multiple organ dysfunction, or mortality.

DESIGN

Prospective cohort study.

SETTING

University hospital intensive care unit.

PATIENTS

A total of 82 critically ill adult patients in four clinically defined groups, namely septic shock (n = 29), sepsis without shock (n = 17), shock without sepsis (n = 22), and nonseptic, nonshock controls (n = 14).

INTERVENTIONS

None.

MEASUREMENT AND MAIN RESULTS

During day 1 of septic shock, peak plasma levels of G-CSF, interleukin (IL)-6, and leukemia inhibitory factor (LIF), but not GM-CSF, were greater than in sepsis or shock alone (p < .001), and were correlated among themselves (rs = 0.44-0.77; p < .02) and with the APACHE II score (rs = 0.25-0.40; p = .03 to .18). G-CSF, IL-6, and UF, and sepsis, shock, septic shock, and APACHE II scores were strongly associated with organ dysfunction or 5-day mortality by univariate analysis. However, multiple logistic regression analysis showed that only septic shock remained significantly associated with organ dysfunction and only APACHE II scores and shock with 5-day mortality. Similarly, peak G-CSF, IL-6, and LIF were poorly predictive of 30-day mortality.

CONCLUSIONS

Plasma levels of G-CSF, IL-6, and LIF are greatly elevated in critical illness, including septic shock, and are correlated with one another and with the severity of illness. However, they are not independently predictive of mortality, or the development of multiple organ dysfunction. GM-CSF was rarely elevated, suggesting different roles for G-CSF and GM-CSF in human septic shock.