A Randomized Noninferiority Trial to Compare Enteral to Parenteral Phosphate Replacement on Biochemistry, Waste, and Environmental Impact and Healthcare Cost in Critically Ill Patients With Mild to Moderate Hypophosphatemia.

OBJECTIVES: Hypophosphatemia occurs frequently. Enteral, rather than IV, phosphate replacement may reduce fluid replacement, cost, and waste. DESIGN: Prospective, randomized, parallel group, noninferiority clinical trial. SETTING: Single center, 42-bed state trauma, medical and surgical ICUs, from April 20, 2022, to July 1, 2022. PATIENTS: Patients with serum phosphate concentration between 0.3 and 0.75 mmol/L. INTERVENTIONS: We randomized patients to either enteral or IV phosphate replacement using electronic medical record-embedded program. MEASUREMENT AND MAIN RESULTS: Our primary outcome was serum phosphate at 24 hours with a noninferiority margin of 0.2 mmol/L. Secondary outcomes included cost savings and environmental waste reduction and additional IV fluid administered. The modified intention-to-treat cohort comprised 131 patients. Baseline phosphate concentrations were similar between the two groups. At 24 hours, mean ( sd ) serum phosphate concentration were enteral 0.89 mmol/L (0.24 mmol/L) and IV 0.82 mmol/L (0.28 mmol/L). This difference was noninferior at the margin of 0.2 mmol/L (difference, 0.07 mmol/L; 95% CI, -0.02 to 0.17 mmol/L). When assigned IV replacement, patients received 408 mL (372 mL) of solvent IV fluid. Compared with IV replacement, the mean cost per patient was ten-fold less with enteral replacement ($3.7 [$4.0] vs. IV: $37.7 [$31.4]; difference = $34.0 [95% CI, $26.3-$41.7]) and weight of waste was less (7.7 g [8.3 g] vs. 217 g [169 g]; difference = 209 g [95% CI, 168-250 g]). C O2 emissions were 60-fold less for comparable phosphate replacement (enteral: 2 g producing 14.2 g and 20 mmol of potassium dihydrogen phosphate producing 843 g of C O2 equivalents). CONCLUSIONS: Enteral phosphate replacement in ICU is noninferior to IV replacement at a margin of 0.2 mmol/L but leads to a substantial reduction in cost and waste.

Clearance of Piperacillin-Tazobactam and Vancomycin During Continuous Renal Replacement With Regional Citrate Anticoagulation.

BACKGROUND: The use of regional citrate anticoagulation during continuous venovenous hemodiafiltration (CVVHDF) has increased worldwide. However, data on its effect on the pharmacokinetics of antibiotics are limited. In this study, the authors aimed to measure the clearance of piperacillin-tazobactam and vancomycin in patients receiving CVVHDF with regional citrate anticoagulation. METHODS: This study measured piperacillin-tazobactam and vancomycin concentrations in patients receiving CVVHDF with regional citrate anticoagulation. Dosing regimens were independently selected by intensivists. Arterial blood and effluent fluid samples were obtained over a single dosing interval and analyzed using ultra-high-performance liquid chromatography with tandem mass spectrometry. RESULTS: Seventeen sampling intervals in 15 patients (9 receiving piperacillin-tazobactam only, 4 receiving vancomycin only, and 2 receiving both) were used. The median overall clearance for piperacillin was 35.2 mL/min [interquartile range (IQR): 32.2-38.6], 70 mL/min (IQR: 62.7-76.2) for tazobactam, and 29.5 mL/min (IQR: 26.2-32) for vancomycin. CONCLUSIONS: This is the first study to quantify the pharmacokinetics of vancomycin and piperacillin-tazobactam in patients receiving CVVHDF with regional citrate anticoagulation. These results indicate high clearance and provide key information to guide optimal dosing.

Association between protocol change to a higher-protein formula with lower energy targets and nutrient delivery in critically ill patients with COVID-19: A retrospective cohort study.

BACKGROUND: Guidelines recommend prioritizing protein provision while avoiding excessive energy delivery to critically ill patients with coronavirus disease 2019 (COVID-19), but there are no prospective studies evaluating such a targeted approach in this group. We aimed to evaluate the effect of a "higher-protein formula protocol" on protein, energy, and volume delivery when compared with standard nutrition protocol. METHODS: This was a retrospective cohort study of adult patients with COVID-19 who received mechanical ventilation for >72 h and enteral nutrition. Before October 2021, the standard nutrition protocol for patients was 0.7 ml/kg/h ideal body weight (IBW) of a 63 g/L protein and 1250 kcal/L formula. From October 2021, we implemented a higher-protein formula protocol for patients with COVID-19. The initial prescription was 0.5 ml/kg/h IBW of a 100 g/L protein and 1260 kcal/L formula with greater emphasis on energy targets being directed by indirect calorimetry when possible. Measured outcomes included protein, energy, and volume delivered. RESULTS: There were 114 participants (standard protocol, 48; higher-protein protocol, 66) with 1324 days of nutrition support. The median (95% CI) differences in protein, energy, and volume delivery between targeted and standard protocol periods were 0.08 g/kg/day (-0.02 to 0.18 g/kg/day), -1.71 kcal/kg/day (-3.64 to 0.21 kcal/kg/day) and -1.5 ml/kg/day (-2.9 to -0.1 ml/kg/day). Thirty-three patients (standard protocol, 7; higher-protein protocol, 26) had 44 indirect calorimetry assessments. There was no difference in measured energy expenditure over time (increased by 0.49 kcal/kg/day [-0.89 to 1.88 kcal/kg/day]). CONCLUSION: Implementation of a higher-protein formula protocol to patients with COVID-19 modestly reduced volume administration without impacting protein and energy delivery.

The association of blood transfusion with mortality after cardiac surgery: cause or confounding? (CME).

BACKGROUND: Bleeding into the chest is a life-threatening complication of cardiac surgery. Blood transfusion has been implicated as an important cause of harm associated with bleeding, based largely on studies demonstrating an independent association between transfusion and mortality. These studies did not, however, consider the possibility that bleeding may in itself be harmful, inasmuch as drains are inefficient at clearing blood from the chest and retained blood may compromise cardiac and lung function. STUDY DESIGN AND METHODS: We undertook a multivariate logistic regression analysis of the risk factors associated with mortality in 2599 consecutive patients undergoing cardiac surgery. Unlike previous studies the risk factors examined included the volume of chest tube drainage at 24 hours. A stratified analysis was also undertaken that compared the adjusted risk of death for patients exposed or not exposed to a postoperative blood transfusion. RESULTS: Blood transfusion was not an independent predictor of mortality (p=0.4). Chest tube drainage was the strongest independent predictor of mortality (p<0.001). In the stratified analysis, chest tube drainage remained an independent predictor of mortality for patients not exposed to a blood transfusion (p<0.01). Furthermore, the risk of death of these patients was no different from patients exposed to a blood transfusion (p=0.7 for interaction). CONCLUSIONS: Our results argue that for patients undergoing cardiac surgery bleeding contributes to mortality through mechanisms unrelated to blood transfusion.

Nebulised heparin for patients with or at risk of acute respiratory distress syndrome: a multicentre, randomised, double-blind, placebo-controlled phase 3 trial.

BACKGROUND: Mechanical ventilation in intensive care for 48 h or longer is associated with the acute respiratory distress syndrome (ARDS), which might be present at the time ventilatory support is instituted or develop afterwards, predominantly during the first 5 days. Survivors of prolonged mechanical ventilation and ARDS are at risk of considerably impaired physical function that can persist for years. An early pathogenic mechanism of lung injury in mechanically ventilated, critically ill patients is inflammation-induced pulmonary fibrin deposition, leading to thrombosis of the microvasculature and hyaline membrane formation in the air sacs. The main aim of this study was to determine if nebulised heparin, which targets fibrin deposition, would limit lung injury and thereby accelerate recovery of physical function in patients with or at risk of ARDS. METHODS: The Can Heparin Administration Reduce Lung Injury (CHARLI) study was an investigator-initiated, multicentre, double-blind, randomised phase 3 trial across nine hospitals in Australia. Adult intensive care patients on invasive ventilation, with impaired oxygenation defined by a PaO2/FiO2 ratio of less than 300, and with the expectation of invasive ventilation beyond the next calendar day were recruited. Key exclusion criteria were heparin allergy, pulmonary bleeding, and platelet count less than 50 X 109/L. Patients were randomly assigned 1:1, with stratification by site and using blocks of variable size and random seed, via a web-based system, to either unfractionated heparin sodium 25 000 IU in 5 mL or identical placebo (sodium chloride 0·9% 5 mL), administered using a vibrating mesh membrane nebuliser every 6 h to day 10 while invasively ventilated. Patients, clinicians, and investigators were masked to treatment allocation. The primary outcome was the Short Form 36 Health Survey Physical Function Score (out of 100) of survivors at day 60. Prespecified secondary outcomes, which are exploratory, included development of ARDS to day 5 among at-risk patients, deterioration of the Murray Lung Injury Score (MLIS) to day 5, mortality at day 60, residence of survivors at day 60, and serious adverse events. Analyses followed the intention-to-treat principle. There was no imputation of missing data. The trial is registered with the Australian and New Zealand Clinical Trials Register, number ACTRN12612000418875 . FINDINGS: Between Sept 4, 2012, and Aug 23, 2018, 256 patients were randomised. Final follow-up was on Feb 25, 2019. We excluded three patients who revoked consent and one ineligible participant who received no intervention. Of 252 patients included in data analysis, the mean age was 58 years (SD 15), 157 (62%) were men, and 118 (47%) had ARDS. 128 (51%) patients were assigned to the heparin group and 124 (49%) to the placebo group, all of whom received their assigned intervention. Survivors in the heparin group (n=97) had similar SF-36 Physical Function Scores at day 60 compared to the placebo group (n=94; mean 53·6 [SD 31·6] vs 48·7 [35·7]; difference 4·9 [95% CI -4·8 to 14·5]; p=0·32). Compared with the placebo group, the heparin group had fewer cases of ARDS develop to day 5 among the at-risk patients (nine [15%] of 62 patients vs 21 [30%] of 71 patients; hazard ratio 0·46 [95% CI 0·22 to 0·98]; p=0·0431), less deterioration of the MLIS to day 5 (difference -0·14 [-0·26 to -0·02]; p=0·0215), similar day 60 mortality (23 [18%] of 127 patients vs 18 [15%] of 123 patients; odds ratio [OR] 1·29 [95% CI 0·66 to 2·53]; p=0·46), and more day 60 survivors at home (86 [87%] of 99 patients vs 73 [73%] of 100 patients; OR 2·45 [1·18 to 5·08]; p=0·0165). A similar number of serious adverse events occurred in each group (seven [5%] of 128 patients in the heparin group vs three [2%] of 124 patients in the placebo group; OR 2·33 [0·59 to 9·24]; p=0·23), which were a transient increase in airway pressure during nebulisation (n=3 in the heparin group), major non-pulmonary bleeding (n=2 in each group), haemoptysis (n=1 in the heparin group), tracheotomy site bleeding (n=1 in the heparin group), and hypoxaemia during nebulisation (n=1 in the placebo group). INTERPRETATION: In patients with or at risk of ARDS, nebulised heparin did not improve self-reported performance of daily physical activities, but was well tolerated and exploratory outcomes suggest less progression of lung injury and earlier return home. Further research is justified to establish if nebulised heparin accelerates recovery in those who have or are at risk of ARDS. FUNDING: Rowe Family Foundation, TR and RB Ditchfield Medical Research Endowment Fund, Patricia Madigan Charitable Trust, and The J and R McGauran Trust Fund.

Targeted full energy and protein delivery in critically ill patients: a study protocol for a pilot randomised control trial (FEED Trial).

BACKGROUND: Current guidelines for the provision of protein for critically ill patients are based on incomplete evidence, due to limited data from randomised controlled trials. The present pilot randomised controlled trial is part of a program of work to expand knowledge about the clinical effects of protein delivery to critically ill patients. The primary aim of this pilot study is to determine whether an enteral feeding protocol using a volume target, with additional protein supplementation, delivers a greater amount of protein and energy to mechanically ventilated critically ill patients than a standard nutrition protocol. The secondary aims are to evaluate the potential effects of this feeding strategy on muscle mass and other patient-centred outcomes. METHODS: This prospective, single-centred, pilot, randomised control trial will include 60 participants who are mechanically ventilated and can be enterally fed. Following informed consent, the participants receiving enteral nutrition in the intensive care unit (ICU) will be allocated using a randomisation algorithm in a 1:1 ratio to the intervention (high-protein daily volume-based feeding protocol, providing 25 kcal/kg and 1.5 g/kg protein) or standard care (hourly rate-based feeding protocol providing 25 kcal/kg and 1 g/kg protein). The co-primary outcomes are the average daily protein and energy delivered to the end of day 15 following randomisation. The secondary outcomes include change in quadriceps muscle layer thickness (QMLT) from baseline (prior to randomisation) to ICU discharge and other nutritional and patient-centred outcomes. DISCUSSION: This trial aims to examine whether a volume-based feeding protocol with supplemental protein increases protein and energy delivery. The potential effect of such increases on muscle mass loss will be explored. These outcomes will assist in formulating larger randomised control trials to assess mortality and morbidity. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN: 12615000876594 UTN: U1111-1172-8563.

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.

Influence of changing endotracheal tube cuff management on antibiotic use for ventilator-associated pneumonia in a tertiary intensive care unit.

BACKGROUND: Routine deflation of the endotracheal tube (ETT) cuff of critically ill patients receiving MV is common in Australia and New Zealand. Literature about ventilatorassociated pneumonia (VAP) and antibiotic use rates with different ETT cuff maintenance practices is lacking. OBJECTIVE: To determine the impact of a change in ETT cuff maintenance from a minimal leak technique to pressure manometry on the administration of antibiotics for VAP. DESIGN, SETTING AND PARTICIPANTS: A prospective, pre- post observational study conducted in a metropolitan tertiary referral intensive care unit. We analysed data from 178 patients receiving MV for > 48 hours during 13 weeks of minimal leak test ETT cuff technique (pre-intervention, n = 92) or 13 weeks of cuff pressure manometry (postintervention, n = 86), separated by 3 weeks' "wash-out". MAIN OUTCOME MEASURES: Primary outcome was the number of patients receiving antibiotics for the indication of VAP. Secondary outcomes were incidence of ventilatorassociated surveillance events, lengths of stay (LOSs) and mortality. RESULTS: Antibiotics were administered for VAP in 24 patients (26.1%) in the pre-intervention period compared with 11 post-intervention patients (12.8%). The univariate antibiotic administraion rate per 100 ventilation days was 15.3% (95% CI, 12.6%-18.4%) v 6.8% (95% CI, 4.9%- 9.3%), and the incident rate ratio (IRR) was 0.45 (95% CI, 0.31-0.64); P < 0.001). After adjustment for ventilation duration, IRR was 0.55 (95% CI, 0.24-1.27); P = 0.160. The ventilator-associated complication incidence rate was lower in the post-intervention group (11.4% v 16.3%; IRR, 0.70 [95% CI, 0.51-0.95]; P = 0.018). After adjustment for duration of MV, IRR was 0.66 (95% CI, 0.25-1.70); P = 0.387. Antibiotic administration for VAP was associated with increased ICU and hospital LOSs, but not with mortality. CONCLUSIONS: ETT cuff pressure manometry is associated with a reduced rate of antibiotic administration for a diagnosis of VAP compared with a minimal leak test technique.

Measurement of physical activity levels in the Intensive Care Unit and functional outcomes: An observational study.

PURPOSE: Primary aims were: (1) objectively quantify levels of physical activity with the sensewear armband mini-fly motion sensor (SWA-MF), (2) evaluate the correlation of SWA-MF measurement of active and resting energy expenditure against the ICU Mobility scale (IMS) and indirect calorimetry respectively. MATERIALS AND METHODS: Adults mechanically ventilated ≥48h and anticipated to remain in ICU≥5days were included. Physical activity (PA) was measured using a SWA-MF (over the first five days); energy expenditure was measured with both the SWA-MF and the Deltatrac II metabolic cart on day three; highest level of mobility was assessed on the IMS. RESULTS: Fifty-five participants performed median [IQR] 16.8 [0.6-152.4] minutes of PA per day (defined as >1.0 metabolic equivalent). A strong correlation between active energy expenditure and highest level of mobility (IMS), r=0.76, p=0.00 was observed on day 5. The SWA-MF demonstrated moderate to good agreement with the Deltatrac II metabolic cart (n=20), intra-class correlation co-efficient=0.71 (p=0.00) for the measurement of energy expenditure on day 3. CONCLUSIONS: Participants demonstrated low levels of PA. Motion sensors may be a promising non-invasive measure of energy expenditure and further investigation is warranted.

Predicting short-term and long-term mortality in elderly emergency patients admitted for intensive care.

OBJECTIVE: The long-term outcomes of intensive care for the growing elderly cohort are not well defined. We explored the predictive factors for 12-month mortality in elderly patients who were admitted to an intensive care unit within 24 hours of emergency department (ED) presentation. DESIGN, SETTING AND PARTICIPANTS: A retrospective cohort study of 506 patients aged 80 years and over who were admitted to the Royal Melbourne Hospital ICU within 24 hours of presentation to the ED, between 1 January 2005 and 1 December 2010. MAIN OUTCOME MEASURES AND RESULTS: After multivariate regression analysis, independent risk factors for mortality 12 months after hospital discharge were the need for mechanical ventilation (odds ratio [OR], 5.16; 95% CI, 3.00-8.86), presence of acute renal failure (OR, 4.71; 95% CI, 2.04-10.84), age (OR, 1.07; 95% CI, 1.01-1.14), Glasgow coma score (GCS) (OR, 0.89; 95% CI, 0.84-0.93) and serum urea level (OR, 1.05; 95% CI, 1.02-1.07). Independent predictors for mortality in the ICU were the presence of acute renal failure (OR, 14.96; 95% CI, 6.50- 34.44), the need for mechanical ventilation (OR, 8.13; 95% CI, 2.77-23.89), and GCS (OR, 0.85; 95% CI, 0.79-0.90). Mortality in the ICU was 16.6%, and 12 months after hospital discharge was 46.3%. CONCLUSIONS: Physiological parameters present on admission to the ICU including acute renal failure, the need for mechanical ventilation, a low GCS and high serum urea level, as well as age, have independent predictive value for 12-month mortality, but comorbidities were not predictive. This may help clinicians with decisions about who will benefit most from intensive care treatment.