Ventilated ICU Patients Research Articles

Persistent carbapenem resistance in mechanically ventilated ICU patients: A before-and-after analysis of the COVID-19 surge

ObjectiveHow did the antimicrobial resistance profile of critically ill patients evolve before, during, and after COVID-19 surge periods? MethodsWe retrospectively analysed all critically ill mechanically ventilated adult patients admitted to eight Brazilian hospitals from January 1st, 2018, to April 30th, 2023. We stratified the patients into three periods based on their admission date: pre-surge (Jan 01/2018-Mar 01/2020), surge (Mar 01/2020 - Oct 01/2021), and post-surge (after Oct 01/2021). We compared the proportion of positive cultures, prevalence of pathogens, and resistance rates across periods using the rate ratios (RR) and their 95% confidence intervals (95% CI). ResultsWe analysed 9,780 ICU patients: 3,718 were in the pre-surge, 3,815 in the surge, and 2,247 in the post-surge period. Patients in the surge period were younger (median: 70 vs. 74 pre-surge vs. 75 post-surge) and presented a higher duration of invasive mechanical ventilation (median 7 vs. 5 days). The utilisation of blood and respiratory cultures increased throughout periods (56.9 pre-surge vs. 69.4 surge vs. 70.4 patients/1,000 patient days post-surge). The isolation of carbapenem-resistant gram-negative bacteria increased during the surge (RR [95% CI]: 1.8 [1.5-2.2], compared to pre-surge), decreased in post-surge (RR [95% CI]: 0.72 [0.6-0.9], and remained higher than pre-surge (RR [95% CI]: 1.3 [1.0-1.6]). Resistance rates for Pseudomonas aeruginosa reduced from 32% in pre- to 23% post-surge, whereas Klebsiella pneumoniae doubled during the surge, 26% to 52%, and remained higher than pre-surge. ConclusionCarbapenem resistance increased during the surge period. Although it decreased post-surge, it remained higher than the rates observed before the pandemic.

Assessment of Energy Consumption Patterns and Validation of Predictive Equations among ICU Patients at Muhimbili National Hospital in Dar es Salaam, Tanzania

Background: Nutritional support in critically-ill patients is one of the most important parameters guarding the prognosis and influencing morbidity and mortality in these patients, owing to that fact, accurate measurement of the resting energy expenditure using Indirect calorimetry is recommended by guidelines as a gold standard. But due to lack of resources and other technicalities predictive equations are conveniently used as surrogates. Aims: This study was intended to examine the extent of malnutrition, poor nutrition support practices and to validate the common used predictive equations in critically-ill patients in our setting. Methodology: A hospital-based descriptive cross-sectional study was conducted on consecutively sampled 110 mechanically ventilated ICU patients at Muhimbili National Hospital Mloganzila. Anthropometric measurements, duration of stay in ICU, Temperature and Minute Volumes were recorded so as to estimate resting energy expenditure, REE from different predictive equations. Using Indirect Calorimetry Module patient’s REE was measured and recorded then a statistical data analyzed using SPSS software version 23. Results: The prevalence of poor nutritional support was 69%; underfeeding and overfeeding were observed in 41.8% and 27.3% of all participants respectively. Prevalence of malnutrition was 51.8%; underweight and overweight were found to be in 29.1% and 22.7% of all participants respectively. The accuracy of predictive equation in ±10% difference was 30%, 45.5%, 46.4% and 68.2% in HB, MSJ, ESPEN and PENN respectively. Conclusion and Recommendation: Malnutrition and Poor Nutritional support are common problems in ICU. Predictive equations have poor accuracy and validity in comparison to indirect calorimetry. Penn State Equation was the most accurate and with the highest agreement with IC.

Effect of esketamine combined with dexmedetomidine on delirium in sedation for mechanically ventilated ICU patients: protocol for a nested substudy within a randomized controlled trial

BackgroundUse of sedatives and analgesics is associated with the occurrence of delirium in critically ill patients receiving mechanical ventilation. Dexmedetomidine reduces the occurrence of delirium but may cause hypotension, bradycardia, and insufficient sedation. This substudy aims to determine whether the combination of esketamine with dexmedetomidine can reduce the side effects and risk of delirium than dexmedetomidine alone in mechanically ventilated patients.MethodsThis single-center, randomized, active-controlled, superiority trial will be conducted at The First Affiliated Hospital of Nanjing Medical University. A total of 134 mechanically ventilated patients will be recruited and randomized to receive either dexmedetomidine alone or esketamine combined with dexmedetomidine, until extubation or for a maximum of 14 days. The primary outcome is the occurrence of delirium, while the second outcomes include the number of delirium-free days; subtype, severity, and duration of delirium; time to first onset of delirium; total dose of vasopressors and antipsychotics; duration of mechanical ventilation; ICU and hospital length of stay (LOS); accidental extubation, re-intubation, re-admission; and mortality in the ICU at 14 and 28 days.DiscussionThere is an urgent need for a new combination regimen of dexmedetomidine due to its evident side effects. The combination of esketamine and dexmedetomidine has been applied throughout the perioperative period. However, there is still a lack of evidence on the effects of this regimen on delirium in mechanically ventilated ICU patients. This substudy will evaluate the effects of the combination of esketamine and dexmedetomidine in reducing the risk of delirium for mechanically ventilated patients in ICU, thus providing evidence of this combination to improve the short-term prognosis. The study protocol has obtained approval from the Medical Ethics Committee (ID: 2022-SR-450).Trial registrationClinicalTrials.gov: NCT05466708, registered on 20 July 2022.

Central venous pressure waveform analysis during sleep/rest: a novel approach to enhance intensive care unit post-extubation monitoring of extubation failure.

This pilot study aimed to investigate the relation between cardio-respiratory parameters derived from Central Venous Pressure (CVP) waveform and Extubation Failure (EF) in mechanically ventilated ICU patients during post-extubation period. This study also proposes a new methodology for analysing these parameters during rest/sleep periods to try to improve the identification of EF. We conducted a prospective observational study, computing CVP-derived parameters including breathing effort, spectral analyses, and entropy in twenty critically ill patients post-extubation. The Dynamic Warping Index (DWi) was calculated from the respiratory component extracted from the CVP signal to identify rest/sleep states. The obtained parameters from EF patients and patients without EF were compared both during arbitrary periods and during reduced DWi (rest/sleep). We have analysed data from twenty patients of which nine experienced EF. Our findings may suggest significantly increased respiratory effort in EF patients compared to those successfully extubated. Our study also suggests the occurrence of significant change in the frequency dispersion of the cardiac signal component. We also identified a possible improvement in the differentiation between the two groups of patients when assessed during rest/sleep states. Although with caveats regarding the sample size, the results of this pilot study may suggest that CVP-derived cardio-respiratory parameters are valuable for monitoring respiratory failure during post-extubation, which could aid in managing non-invasive interventions and possibly reduce the incidence of EF. Our findings also indicate the possible importance of considering sleep/rest state when assessing cardio-respiratory parameters, which could enhance respiratory failure detection/monitoring.

Advanced waveform analysis of diaphragm surface EMG allows for continuous non-invasive assessment of respiratory effort in critically ill patients at different PEEP levels

BackgroundRespiratory effort should be closely monitored in mechanically ventilated ICU patients to avoid both overassistance and underassistance. Surface electromyography of the diaphragm (sEMGdi) offers a continuous and non-invasive modality to assess respiratory effort based on neuromuscular coupling (NMCdi). The sEMGdi derived electrical activity of the diaphragm (sEAdi) is prone to distortion by crosstalk from other muscles including the heart, hindering its widespread use in clinical practice. We developed an advanced analysis as well as quality criteria for sEAdi waveforms and investigated the effects of clinically relevant levels of PEEP on non-invasive NMCdi.MethodsNMCdi was derived by dividing end-expiratory occlusion pressure (Pocc) by sEAdi, based on three consecutive Pocc manoeuvres at four incremental (+ 2 cmH2O/step) PEEP levels in stable ICU patients on pressure support ventilation. Pocc and sEAdi quality was assessed by applying a novel, automated advanced signal analysis, based on tolerant and strict cut-off criteria, and excluding inadequate waveforms. The coefficient of variations (CoV) of NMCdi after basic manual and automated advanced quality assessment were evaluated, as well as the effect of an incremental PEEP trial on NMCdi.Results593 manoeuvres were obtained from 42 PEEP trials in 17 ICU patients. Waveform exclusion was primarily based on low sEAdi signal-to-noise ratio (Ntolerant = 155, 37%, Nstrict = 241, 51% waveforms excluded), irregular or abrupt cessation of Pocc (Ntolerant = 145, 35%, Nstrict = 145, 31%), and high sEAdi area under the baseline (Ntolerant = 94, 23%, Nstrict = 79, 17%). Strict automated assessment allowed to reduce CoV of NMCdi to 15% from 37% for basic quality assessment. As PEEP was increased, NMCdi decreased significantly by 4.9 percentage point per cmH2O.ConclusionAdvanced signal analysis of both Pocc and sEAdi greatly facilitates automated and well-defined identification of high-quality waveforms. In the critically ill, this approach allowed to demonstrate a dynamic NMCdi (Pocc/sEAdi) decrease upon PEEP increments, emphasising that sEAdi-based assessment of respiratory effort should be related to PEEP dependent diaphragm function. This novel, non-invasive methodology forms an important methodological foundation for more robust, continuous, and comprehensive assessment of respiratory effort at the bedside.

Measuring pain or discomfort during routine nursing care in lightly sedated mechanically ventilated intensive care patients: A prospective preliminary cohort study

BackgroundPain is routinely measured on mechanically ventilated ICU patients. However, the tools used are not designed to discriminate between pain and non-pain discomfort, a distinction with therapeutic implications. ObjectivesTo evaluate whether clinical measurement tools can discern both pain and non-pain discomfort. MethodsA prospective observational cohort study was conducted in a General ICU at a tertiary Medical Center in Israel. The Behavior Pain Scale (BPS) and Visual Analog Scale (VAS) of Discomfort were simultaneously assessed by a researcher and bedside nurse on thirteen lightly sedated patients during 71 routine nursing interventions in lightly sedated, mechanically ventilated, adult patients. Patients were asked whether they were in pain due to these interventions. ResultsStatistically significant increases from baseline during interventions were observed [median change: 1.00 (-1–5), 1.5(-4–8.5), p < 0.001] as measured by BPS and VAS Discomfort Scale, respectively. BPS scores ranged between 4 and 6 when the majority (53 %) of the patients replied that they had no pain but were interpreted by the clinicians as discomfort. Endotracheal suctioning caused the greatest increase in BPS and VAS, with no statistically significant differences in BPS and VAS Discomfort Scale scores whether patients reported or did not report pain. A BPS>6 had a higher sensitivity and specificity to reported pain (accuracy of 76 %) compared to a BPS of 4–6. ConclusionsStandard assessments are sensitive to pain caused by routine nursing care interventions. However, this study presents evidence that among lightly sedated ICU patients, moderate BPS scores could also measure non-pain discomfort. ICU nurses should be aware that signs of unpleasantness measured by a pain scale could reflect non-pain discomfort.

Outcomes associated with ventilator-associated events (VAE), respiratory infections (VARI), pneumonia (VAP) and tracheobronchitis (VAT) in ventilated pediatric ICU patients: A multicentre prospective cohort study

ObjectivesAn objective categorization of respiratory infections based on outcomes is an unmet clinical need. Ventilator-associated pneumonia and tracheobronchitis remain used in clinical practice, whereas ventilator-associated events (VAE) are limited to surveillance purposes. Research methodology/designThis was a secondary analysis from a multicentre observational prospective cohort study. VAE were defined as a sustained increase in minimum Oxygen inspired fraction (FiO2) and/or Positive end-expiratory pressures (PEEP) of ≥ 0.2/2 cm H2O respectively, or an increase of 0.15 FiO2 + 1 cm H20 positive end-expiratory pressures for ≥ 1 calendar-day. Setting15 Paediatric Intensive Care Units. Main outcome measuresMechanical ventilation duration, intensive care and hospital length of stay; (LOS) and mortality. ResultsA cohort of 391 ventilated children with an age (median, [Interquartile Ranges]) of 1 year[0.2–5.3] and 7 days[5–10] of mechanical ventilation were included. Intensive care and hospital stays were 11 [7–19] and 21 [14–39] days, respectively. Mortality was 5.9 %. Fifty-eight ventilator-associated respiratory infections were documented among 57 patients: Seventeen (29.3 %) qualified as ventilator-associated pneumonia (VAP) and 41 (70.7 %) as ventilator-associated tracheobronchitis (VAT). Eight pneumonias and 16 tracheobronchitis (47 % vs 39 %,P = 0.571) required positive end-expiratory pressure or oxygen increases consistent with ventilator-associated criteria. Pneumonias did not significantly impact on outcomes when compared to tracheobronchitis. In contrast, infections (pneumonia or tracheobronchitis) following VAEs criteria were associated with > 6, 8 and 15 extra-days of ventilation (16 vs 9.5, P = 0.001), intensive care stay (23.5 vs 15; P = 0.004) and hospital stay (39 vs 24; P = 0.015), respectively. ConclusionWhen assessing ventilated children with respiratory infections, VAE apparently is associated with higher ventilator-dependency and LOS compared with pneumonia or tracheobronchitis. Implications for practiceIncorporating the modification of ventilatory settings for further categorization of the respiratory infections may facilitate therapeutic management among ventilated patients.

Evaluation of Recurrence Rates of Pseudomonas Pneumonia in Mechanically Ventilated ICU Patients Receiving ≤7 Versus &gt;7 Days of Antibiotic Therapy

Background Pseudomonas aeruginosa (PA) is commonly implicated in ventilator-associated pneumonia (VAP). Consensus guidelines for VAP recommend a 7-day course of appropriate antibiotics. However, recent studies have shown higher recurrence rates of PA pneumonia with shorter courses of antibiotics. This study was designed to compare PA pneumonia recurrence rates in patients who received appropriate antibiotics for ≤7 days vs &gt;7 days. Methods A retrospective, single-center, observational cohort study of adults diagnosed with PA-VAP between January 2017 and May 2022 was conducted. Patients were divided into a &gt;7-day cohort or a ≤7-day cohort based on duration of appropriate antibiotics. The primary outcome was the recurrence rate of PA pneumonia. Results A total of 106 patients were included, 59 in the &gt;7-day cohort and 47 in the ≤7-day cohort. The median (interquartile range) duration of appropriate antipseudomonal therapy was 12 days (8–18 days) in the &gt;7-day cohort and 7 days (6–7 days) in the ≤7-day cohort. Pseudomonas aeruginosa recurrence was observed in 15 (25.4%) patients in the &gt;7-day cohort and 20 (42.6%) patients in the ≤7-day cohort (P = 0.059). Over 33% of patients in the &gt;7-day cohort had persistently positive PA cultures after at least 7 days of appropriate antibiotic therapy. Conclusion Extending duration of antipseudomonal antibiotics beyond 7 days did not significantly reduce the recurrence of PA pneumonia. However, the lower rate of recurrence in the &gt;7-day group and high rate of persistent positive cultures may be clinically significant, suggesting a role for extended treatment. Further prospective studies are needed to determine the optimal duration of therapy for PA-VAP.

Successful Versus Failed Transition From Controlled Ventilation to Pressure Support Ventilation in COVID-19 Patients: A Retrospective Cohort Study.

In patients with COVID-19 respiratory failure, controlled mechanical ventilation (CMV) is often necessary during the acute phases of the disease. Weaning from CMV to pressure support ventilation (PSV) is a key objective when the patient's respiratory functions improve. Limited evidence exists regarding the factors predicting a successful transition to PSV and its impact on patient outcomes. Retrospective observational cohort study. Twenty-four Italian ICUs from February 2020 to May 2020. Mechanically ventilated ICU patients with COVID-19-induced respiratory failure. The transition period from CMV to PSV was evaluated. We defined it as "failure of assisted breathing" if the patient returned to CMV within the first 72 hours. Of 1260 ICU patients screened, 514 were included. Three hundred fifty-seven patients successfully made the transition to PSV, while 157 failed. Pao2/Fio2 ratio before the transition emerged as an independent predictor of a successful shift (odds ratio 1.00; 95% CI, 0.99-1.00; p = 0.003). Patients in the success group displayed a better trend in Pao2/Fio2, Paco2, plateau and peak pressure, and pH level. Subjects in the failure group exhibited higher ICU mortality (hazard ratio 2.08; 95% CI, 1.42-3.06; p < 0.001), an extended ICU length of stay (successful vs. failure 21 ± 14 vs. 27 ± 17 d; p < 0.001) and a longer duration of mechanical ventilation (19 ± 18 vs. 24 ± 17 d, p = 0.04). Our study emphasizes that the Pao2/Fio2 ratio was the sole independent factor associated with a failed transition from CMV to PSV. The unsuccessful transition was associated with worse outcomes.

Early Mobilization Using a Mobile Patient Lift in the ICU: A Randomized Controlled Trial.

To ascertain whether a mobile patient lift facilitates early mobilization in ventilated ICU patients. A single-center, open-label, randomized controlled trial. An academic ICU in Tokyo. Eighty patients were admitted to ICU and expected ventilation for at least 48 hours. In the intervention group, in addition to the rehabilitation protocol received by the control group, patients were assisted in sitting, standing, transfers, and walking using the mobile patient lift. The intervention group predominantly stood faster than the control group (1.0 vs. 3.0 d, p < 0.01). The Intervention group also had significantly higher Functional Status Score-ICU scores at ICU discharge. However, the Medical Research Council score and Barthel index at discharge, length of ICU stay, and number of ventilator-free days did not differ between the two groups. The use of mobile patient lifts facilitates the earlier standing of patients on ventilators. This may contribute to patients improved physical function in the ICU. The study protocol was registered with the University Hospital Medical Information Network (UMIN) under the registration number UMIN000044965. Registered July 30, 2021.

Identification and responses to positivity violations in longitudinal studies: an illustration based on invasively mechanically ventilated ICU patients

Identification and estimation of causal effects relies on the positivity assumption, which states that there should be some positive probability of having each treatment level of interest, regardless of covariate levels. Violations of positivity can lead to both non-identified target causal parameters, estimator bias and inflated variance. We discuss reasons for and responses to positivity violations when the causal effect of interest involves treatments or exposures at multiple time points. For illustration, we use a data example involving the cumulative effect of controlling arterial oxygen tension over time on death among ICU patients receiving invasive mechanical ventilation. We distinguish between practical (by chance) violations that relate to sample size and structural violations in which certain treatment levels occur with zero probability for certain covariate levels. We focus on responses that either redefines the target population, e.g. via trimming or redefines the intervention making it more dynamic or more stochastic. Supported by a simulation study, we illustrate how these responses help restore needed positivity but also modify the target causal parameter. We further introduce an inability to intervene variable and show how such a variable will often be a time-dependent confounder and essential when addressing structural positivity violations in longitudinal settings.

Diaphragm excursions as proxy for tidal volume during spontaneous breathing in invasively ventilated ICU patients

There is a need to monitor tidal volume in critically ill patients with acute respiratory failure, given its relation with adverse clinical outcome. However, quantification of tidal volume in non-intubated patients is challenging. In this proof-of-concept study, we evaluated whether ultrasound measurements of diaphragm excursion could be a valid surrogate for tidal volume in patients with respiratory failure. Diaphragm excursions and tidal volumes were simultaneously measured in invasively ventilated patients (N = 21) and healthy volunteers (N = 20). Linear mixed models were used to estimate the ratio between tidal volume and diaphragm excursion. The tidal volume–diaphragm excursion ratio was 201 mL/cm in ICU patients [95% confidence interval (CI) 161–240 mL/cm], and 361 (294–428) mL/cm in healthy volunteers. An excellent association was shown within participants (R2 = 0.96 in ICU patients, R2 = 0.90 in healthy volunteers). However, the differences between observed tidal volume and tidal volume as predicted by the linear mixed models were considerable: the 95% limits of agreement in Bland–Altman plots were ± 91 mL in ICU patients and ± 396 mL in healthy volunteers. Likewise, the variability in tidal volume estimation between participants was large. This study shows that diaphragm excursions measured with ultrasound correlate with tidal volume, yet quantification of absolute tidal volume from diaphragm excursion is unreliable.

Passive leg raising test induced changes in plethysmographic variability index to assess fluid responsiveness in critically ill mechanically ventilated patients with acute circulatory failure

BackgroundPassive leg raising (PLR) reliably predicts fluid responsiveness but requires a real-time cardiac index (CI) measurement or the presence of an invasive arterial line to achieve this effect. The plethysmographic variability index (PVI), an automatic measurement of the respiratory variation of the perfusion index, is non-invasive and continuously displayed on the pulse oximeter device. We tested whether PLR-induced changes in PVI (ΔPVIPLR) could accurately predict fluid responsiveness in mechanically ventilated patients with acute circulatory failure. MethodsThis was a secondary analysis of an observational prospective study. We included 29 mechanically ventilated patients with acute circulatory failure in this study. We measured PVI (Radical-7 device; Masimo Corp., Irvine, CA) and CI (Echocardiography) before and during a PLR test and before and after volume expansion of 500 mL of crystalloid solution. A volume expansion-induced increase in CI of >15% defined fluid responsiveness. To investigate whether ΔPVIPLR can predict fluid responsiveness, we determined areas under the receiver operating characteristic curves (AUROCs) and gray zones for ΔPVIPLR. ResultsOf the 29 patients, 27 (93.1%) received norepinephrine. The median tidal volume was 7.0 [IQR: 6.6–7.6] mL/kg ideal body weight. Nineteen patients (65.5%) were classified as fluid responders (increase in CI > 15% after volume expansion). Relative ΔPVIPLR accurately predicted fluid responsiveness with an AUROC of 0.89 (95%CI: 0.72–0.98, p < 0.001). A decrease in PVI ≤ −24.1% induced by PLR detected fluid responsiveness with a sensitivity of 95% (95%CI: 74–100%) and a specificity of 80% (95%CI: 44–97%). Gray zone was acceptable, including 13.8% of patients. The correlations between the relative ΔPVIPLR and changes in CI induced by PLR and by volume expansion were significant (r = −0.58, p < 0.001, and r = −0.65, p < 0.001; respectively). ConclusionsIn sedated and mechanically ventilated ICU patients with acute circulatory failure, PLR-induced changes in PVI accurately predict fluid responsiveness with an acceptable gray zone. Trial registrationClinicalTrials.govNCT03225378.

Resting energy expenditure measured by indirect calorimetry in mechanically ventilated patients during ICU stay and post-ICU hospitalization: A prospective observational study

PurposeThe metabolic course during and after critical illness is unclear. We performed repeated indirect calorimetry (IC) measurements during ICU- and post-ICU hospitalization to determine resting energy expenditure (REE). MethodsProspective observational design. In ventilated ICU patients, IC measurements were performed every three days until hospital discharge. Measured REE as predicted by the Harris-Benedict equation (HBE-REE) and 25 kcal/adjusted body weight/day (25-REE) were compared. ResultsIn 56 patients (38% females, 71[13]years, BMI 29(27;31)kg/m2), 189 ICU IC measurements were performed. Measured REE did not differ from HBE-REE at ICU admission, but was lower than 25-REE. Measured REE was increased compared to baseline on ICU-admission-day four (29(29–30)kcal/kg/day; mean difference 3.1(1.4–4.9)kcal/kg/day, p < 0.001) and thereafter during ICU admission. During post-ICU ward stay, 44 measurements were performed in 23 patients, showing a higher mean REE than during ICU stay (33(31–35)kcal/kg/day; mean difference 2.6(1.2–3.9)kcal/kg/day, p < 0.001). The REE in the ICU and ward was >110% of HBE-REE from day four onwards. ConclusionsCritically ill mechanically ventilated patients were shown to have a resting energy expenditure (REE) > 110% of predicted REE on ICU admission day four and thereafter. Indirect calorimetry measurements suggest that the mean energy requirements during post-ICU hospitalization are higher than those in the ICU.

Dexmedetomidine versus propofol as a sedative on reduction of intubation rate in patients undergoing noninvasive ventilation in ICU patients

Dexmedetomidine versus propofol as a sedative on reduction of intubation rate in patients undergoing noninvasive ventilation in ICU patients

Driving Pressure: What Is the Harm?

Driving Pressure: What Is the Harm?

Oxygen therapy in intensive care

Pulse oximetry has high sensitivity but low specificity for detecting hypoxemia. Arterial blood gas analyses are the gold standard for monitoring O2 therapy. Venous blood gas analyses should not be used in this setting. TARGET VALUES OF O2 THERAPY: The target range of acute O2 therapy for ventilated patients and nonventilated patients not at risk of hypercapnia should be between 92% and 96% for oxygen saturation (SpO2) measured by pulse oximetry. Indications for high-dose O2 therapy without a target range in critical care include carbon monoxide poisoning and patients with severe respiratory distress when SpO2 cannot be derived. Hyperoxemia, i.e., SpO2 values above 96%, has not improved survival in randomized trials of predominantly ventilated ICU patients. Under hyperoxemia in nonventilated patients at risk of hypercapnia (e.g., patients with chronic obstructive pulmonary disease), one in three patients is at risk of increasing carbon dioxide. Therefore, a target SpO2 of 88-92% should be aimed for in these patients. O2 TARGET RANGES ON EXTRACORPOREAL PROCEDURES: There are no randomized studies recommending other SpO2 target ranges for patients on extracorporeal procedures. These patients should always be monitored with arterial blood gases-in the case of peripheral VA-ECMO on the right arm and downstream of the oxygenator. HIGH-FLOW OXYGEN THERAPY FOR ACUTE HYPERCAPNIC RESPIRATORY FAILURE: High-flow oxygen therapy (HFNC) was not associated with reduced in-hospital mortality compared with conventional O2 in a meta-analysis of predominantly patients with acute hypoxemia (type I respiratory failure), although intubation rates were reduced. Also, in acute hypercapnic respiratory failure (type II), HFNC with high flow rates is not inferior to noninvasive ventilation (NIV).

Identification of Distinct Clinical Phenotypes of Heterogeneous Mechanically Ventilated ICU Patients Using Cluster Analysis

This retrospective study aimed to derive the clinical phenotypes of ventilated ICU patients to predict the outcomes on the first day of ventilation. Clinical phenotypes were derived from the eICU Collaborative Research Database (eICU) cohort via cluster analysis and were validated in the Medical Information Mart for Intensive Care (MIMIC-IV) cohort. Four clinical phenotypes were identified and compared in the eICU cohort (n = 15,256). Phenotype A (n = 3112) was associated with respiratory disease, had the lowest 28-day mortality (16%), and had a high extubation success rate (~80%). Phenotype B (n = 3335) was correlated with cardiovascular disease, had the second-highest 28-day mortality (28%), and had the lowest extubation success rate (69%). Phenotype C (n = 3868) was correlated with renal dysfunction, had the highest 28-day mortality (28%), and had the second-lowest extubation success rate (74%). Phenotype D (n = 4941) was associated with neurological and traumatic diseases, had the second-lowest 28-day mortality (22%), and had the highest extubation success rate (>80%). These findings were validated in the validation cohort (n = 10,813). Additionally, these phenotypes responded differently to ventilation strategies in terms of duration of treatment, but had no difference in mortality. The four clinical phenotypes unveiled the heterogeneity of ICU patients and helped to predict the 28-day mortality and the extubation success rate.

Comparison of resting energy expenditure measured with metabolic cart and calculated with predictive formulas in critically ill patients on mechanical ventilation

IntroductionThe purpose was to compare the resting energy expenditure (REE) measured with the Q-NRG™+ metabolic-cart (MREE) with REE predicted by equations (the Harris-Benedict formula and an equation developed in ward, REE-HB and REE-W, respectively). We also aimed to assess the agreement of the measurements of oxygen consumption (V̇O2) and carbon dioxide production (V̇CO2) at different inspired fractions of oxygen (FiO2). Methods27 mechanically ventilated ICU patients were enrolled. V̇O2 and V̇CO2 were measured by Q-NRG™+ during breathing 40% and 60% FiO2. MREE was compared with REE-W and REE-HB normalized for body weight. ResultsV̇O2 was 233.0 (95.2) ml/min and 217.5 (89.8) ml/min at FiO2 40% and 60%, respectively (NS). V̇CO2 was 199.0 (91.7) ml/min at FiO2 40%, and 197.5 (85.5) ml/min at FiO2 60% (NS). The REE estimated from the equations was significantly different from the MREE. The best agreement was found for the Harris-Benedict equation without correction for stress-factors. Harris-Benedict equation corrected overestimates REE. ConclusionsThis new metabolic cart Q-NRG™+ provides a concordance of values for V̇O2 and V̇CO2 when measured at different FiO2, and is a reliable tool for estimating energy expenditure and assessing the nutritional needs of the patient. This study demonstrates that the estimation of REE using predictive formulas does not allow accurate calculation of metabolic demands in ventilated intensive care patient. However, predictive equations allow for a rapid assessment of REE and calculation of the amount of energy derived from different substrates.

Multiple-site decontamination in mechanically ventilated ICU patients: A real-life study

IntroductionDecontamination regimen decreases acquired infection (ICU-AI) incidence but has remained controversial, mostly because it contains a course of intravenous antibiotic. Multiple-site decontamination (MSD), which does not include systemic antibiotics, has been less widely studied but is associated with lower risks of ventilator-associated pneumonia (VAP), bloodstream infection (BSI) and multidrug resistant micro-organism (MDRO) acquisition. We aimed to confirm these favorable outcomes. MethodsA prospective pre/post-observational study was conducted in 5 ICUs in western France. Among them, 4 implemented MSD, whereas the fifth applied standard care (SC) throughout the study period. Patients who required intubation were eligible for study and divided into two groups: the MSD group if they were admitted to an ICU that already implemented MSD, or the SC group. The primary objective was to measure ICU-AI incidence. ResultsClose to 1400 (1346) patients were available for analysis (334 in the MSD and 1012 patients in the SC group). In a multivariable Poisson regression model, MSD was independently associated with decreased incidence of ICU-AI (IRR = 0.33; 95 %CI [0.18–0.60] p < 0.001). Non-parsimonious propensity-score matching resulted in 334 patient-pairs with well-balanced baseline characteristics. There was a lower incidence of ICU-AI(6.3 % vs 20.7 % p < 0.001), VAP (3.6 % vs 16.2 % p < 0.001) and BSI (3.0 % vs 7.2 % p = 0.029) in the MSD group as compared with the SC group. Five (1.5 %) and 11 (3.3 %) patients respectively acquired MDRO (p = 0.206). ConclusionMSD is associated with decreased risk of ICU-AI, VAP and BSI, with no increase in MDRO acquisition.