Factors associated with mortality in acute respiratory failure patients without acute respiratory distress syndrome.

Background: Excess tidal volume and driving pressure were associated with increased mortality in patients with acute respiratory distress syndrome (ARDS). Still, the appropriate mechanical ventilation strategy for patients who do not have ARDS needs to be understood. This study aimed to identify risk factors for mortality in acute respiratory failure patients without ARDS. Methods: We included all mechanically ventilated patients who did not meet the criteria for ARDS and were admitted to the medical intensive care unit (ICU) from October 2017 to September 2018. Patients who had tracheostomy before admission, were intubated for more than 24 hours before transfer to ICU, or underwent extracorporeal membrane oxygenation within 24 hours of ICU admission were excluded. Clinical and physiologic data were recorded and compared between survived and non-survived patients. Results: Of 289 patients with acute respiratory failure, 134 patients without ARDS were included; 69 (51%) died within 28 days. Demographics, principal diagnosis, and lung injury score on the first day of admission were not significantly different between survived and non-survived patients. In multivariate analysis, higher peak inspiratory pressure (PIP) during the first 3 days of admission [odds ratio (OR) 1.11, 95% confidence interval (CI): 1.01-1.22, P=0.04], higher sequential organ failure assessment score (OR 1.15, 95% CI: 1.04-1.28, P=0.008) and underlying cerebrovascular diseases (OR 7.09, 95% CI: 1.78-28.28, P=0.006) were independently associated with mortality in these patients, whereas dynamic lung compliance (Cdyn) and respiratory rate were not associated with mortality in the multivariate model. Conclusions: Mortality was high in mechanically ventilated patients without ARDS. Higher PIP is a potentially modifiable risk factor for mortality in these patients, independent of the baseline Cdyn. Underlying cerebrovascular diseases and increased disease severity are also independent factors associated with 28-day mortality.

Tracheostomy-related data from an intensive care unit for two consecutive years before the COVID-19 pandemic.

BACKGROUND: Tracheostomy is commonly used in intensive care unit (ICU) patients who are expected to be on long-term mechanical ventilation or suffer from emergency upper airway obstruction. However, some studies have conflicting findings regarding the optimal technique and its timing and benefits. AIM: To provide evidence of practice, characteristics, and outcome concerning tracheostomy in an ICU of a tertiary care hospital. METHODS: This was a retrospective cohort study including adult critical care patients in a single ICU for two consecutive years. Patients' demographic characteristics, severity of illness (APACHE II score), level of consciousness [Glasgow Coma Scale (GCS)], comorbidities, timing and type of tracheostomy procedure performed and outcome were recorded. We defined late as tracheostomy placement after 8 days or no tracheotomy. RESULTS: Data of 660 patients were analyzed (median age of 60 years), median APACHE II score of 19 and median GCS score of 12 at admission. Tracheostomy was performed in 115 patients, of whom 63 had early and 52 late procedures. Early tracheostomy was mainly executed in case of altered level of consciousness and severe critical illness polyneuromyopathy, however there were no significant statistical results (47.6% vs 36.5%, P = 0.23) and (23.8% vs 19.2%, P = 0.55) respectively. Regarding the method selected, early surgical tracheostomy (ST) was conducted in patients with maxillofacial injuries (50.0% vs 0.0%, P = 0.033), whereas late surgical tracheostomy was selected for patients with goiter (44.4% vs 0.0% P = 0.033). Patients with early tracheostomy spent significantly fewer days on mechanical ventilation (15.3 ± 8.5 vs 22.8 ± 9.6, P < 0.001) and in ICU in general (18.8 ± 9.1 vs 25.4 ± 11.5, P < 0.001). Percutaneous dilatation tracheostomy (PDT) vs ST was preferable in older critical care patients in the case of Central Nervous System underlying cause of admission (62.5% vs 26.3%, P = 0.004). ST was the method of choice in compromised airway (31.6%, vs 7.3% P = 0.008). A large proportion of patients (88/115) with tracheostomy managed to wean from mechanical ventilation and were transferred out of the ICU (100% vs 17.4%, P < 0.001). CONCLUSION: PDT was performed more frequently in our cohort. This technique did not affect mechanical ventilation days, ventilator-associated pneumonia (VAP), ICU length of stay, or survival. No complications were observed in the percutaneous or surgical tracheostomy groups. Patients undergoing early tracheostomy benefited in terms of mechanical ventilation days and ICU length of stay but not of discharge status, presence of VAP, or survival.

Peripheral perfusion index as a predictor of reintubation in critically ill surgical patients.

PURPOSE: We aimed to evaluate the ability of the peripheral perfusion index (PPI) to predict reintubation of critically ill surgical patients. METHODS: This prospective observational study included mechanically ventilated adults who were extubated after a successful spontaneous breathing trial (SBT). The patients were followed up for the next 48 h for the need for reintubation. The heart rate, systolic blood pressure, respiratory rate, peripheral arterial oxygen saturation (SpO2), and PPI were measured before-, at the end of SBT, 1 and 2 h postextubation. The primary outcome was the ability of PPI 1 h postextubation to predict reintubation using area under the receiver operating characteristic curve (AUC) analysis. Univariate and multivariate analyses were performed to identify predictors for reintubation. RESULTS: Data from 62 patients were analysed. Reintubation occurred in 12/62 (19%) of the patients. Reintubated patients had higher heart rate and respiratory rate; and lower SpO2 and PPI than successfully weaned patients. The AUC (95%confidence interval) for the ability of PPI at 1 h postextubation to predict reintubation was 0.82 (0.71-0.91) with a negative predictive value of 97%, at a cutoff value of ≤ 2.5. Low PPI and high respiratory rate were the independent predictors for reintubation. CONCLUSION: PPI early after extubation is a useful tool for prediction of reintubation. Low PPI is an independent risk factor for reintubation. A PPI > 2.5, one hour after extubation can confirm successful extubation.

Ventilator-tube holder for mobilising patients with a tracheostomy: A pilot usability study (TrachVest).

INTRODUCTION: Patients in intensive care may have a tracheostomy and be dependent on a respiratory ventilator while yet conscious and able to mobilise. Early rehabilitation is known to be key to patient recovery. However, for these patients, therapy staff members are required to manage the ventilator tubing in addition to other patient-connected equipment whilst focussing on patient mobility and progress. A technical garment (TrachVest) was designed to hold the ventilator tubing securely during these therapeutic mobilisations. METHODS: We conducted a mixed-methods study to evaluate the use of this garment in an intensive care unit setting. The aim was to determine potential effects on patient safety, its potential benefits, and usability. Research methods included direct observations, user questionnaires (quantitative and qualitative), and staff focus groups. RESULTS: A total of 14 therapy sessions with the garment were observed, involving nine patients and 10 staff. Eleven staff members participated in two focus groups, including two previously involved in the therapy sessions. Therapy sessions consisted of a range of activities including sitting on the edge of the bed, transferring from bed to chair (including use of hoists), and mobilising with walking aids. Overall, staff members felt that the garment was easy to use and would likely improve patient safety during mobilisations. The main benefits were staff reassurance, allowing them to focus on therapy, and in potentially reducing the number of staff members needed for particular activities. Patient characteristics were found to be influential on the perceived utility, and TrachVest may have greater benefit for patients who have greater physical function (e.g., able to actively participate in rehabilitation) and can mobilise at least from bed to chair. Experience of using the TrachVest and of patient capabilities was thought to be key to knowing when it would be most useful. CONCLUSION: Within this pilot usability study, participants, both staff and patients, reported that the TrachVest garment designed to support ventilator tubing during rehabilitation to be highly useable and beneficial to supporting rehabilitation in this patient group.

Comparing different postoperative sedation strategies for patients in the intensive care unit after cardiac surgery: A systematic review of randomized controlled trials and network meta-analysis.

BACKGROUND: Various postoperative sedation protocols with different anaesthetics lead to profound effects on the outcomes for post-cardiac surgery patients. However, a comprehensive analysis of optimal postoperative sedation strategies for patients in the intensive care unit (ICU) after cardiac surgery is lacking. METHODS: We systematically searched for randomized controlled trials (RCTs) in databases including PubMed and Embase. The primary outcome measured the duration of mechanical ventilation (MV) in the ICU, and the secondary outcome encompassed the length of stay (LOS) in the ICU and hospital and the monitoring adverse events. RESULTS: The literature included 18 RCTs (1652 patients) with 13 sedation regimens. Dexmedetomidine plus ketamine and sevoflurane were associated with a significantly reduced duration of MV when compared with propofol. Our results also suggested that dexmedetomidine plus ketamine may associated with a shorter LOS in ICU, and sevoflurane associated with a shorter LOS in the hospital, respectively. CONCLUSIONS: The combination of dexmedetomidine and ketamine seems to be a better option for adult patients needing sedation after cardiac surgery, and the incidence of side effects is lower with dexmedetomidine. These findings have potential implications for medication management in the perioperative pharmacotherapy of cardiac surgery patients.

Outcome of Guillain-Barré Syndrome with bulbar palsy.

BACKGROUND: Elective intubation is advocated in Guillain-Barré syndrome (GBS) with bulbar palsy to prevent aspiration pneumonia and lung collapse. We evaluate the outcome of GBS patients with bulbar palsy, and also compare the risks and benefits of intubation and MV in them. METHODS: 187 GBS patients with bulbar palsy from a cohort of 547 GBS registry were analyzed. Detailed clinical records and peak disability on a 0-6 GBS Disability Scale (GBSDS) were noted. The patients were intubated if arterial blood gas (ABG) analysis revealed hypoxia, hypercarbia or acidosis. The patients with normal ABG parameters were fed by nasogastric tube, and nursed in lateral position. Occurrence of pneumonia, in-hospital death and outcomes at 6-months were classified as complete (GBSDS <2), partial (GBSDS 2-3) and poor (GBSDS >3). RESULTS: 76/187(40.6%) patients required MV, and they had a shorter duration of illness (p = 0.007), higher peak disability (p < 0.001), autonomic dysfunction (p < 0.001) and more frequently received IVIg (p = 0.02). Pneumonia (63% vs 10.8%; p < 0.001) and in-hospital deaths (7.9% vs 1.8%; p = 0.06) were more frequent in MV group compared to nasogastric fed group. At 6-months,104 (55.6%) patients recovered completely. On multivariate analysis, the independent predictors of poor outcome were peak disability [Adjusted Odds Ratio (AOR) 9.84, 95% Confidence Interval (CI) 3.15-30.74, p < 0.0001], day of hospitalization from disease onset (AOR 1.09, 95% Cl 1.01-1.01; p=0.009) and requirement of MV (AOR 0.10; 95% 0.02-0.50; p = 0.005). CONCLUSION: GBS patients with bulbar palsy may be managed by nasogastric feeding and nursing in lateral position without increasing the risk of pneumonia. Mechanical ventilation based on ABG does not worsen outcomes of GBS with bulbar palsy.

Effect of Aspirin Use on the Adverse Outcomes in Patients Hospitalized for COVID-19.

Background: Coronavirus disease 2019 (COVID-19) triggers multiple components of the immune system and causes inflammation of endothelial walls across vascular beds, resulting in respiratory failure, arterial and venous thrombosis, myocardial injury, and multi-organ failure leading to death. Early in the COVID-19 pandemic, aspirin was suggested for the treatment of symptomatic individuals, given its analgesic, antipyretic, anti-inflammatory, anti-thrombotic, and antiviral effects. This study aimed to evaluate the association of aspirin use with various clinical outcomes in patients hospitalized for COVID-19. Methods: This was a retrospective study involving patients aged ≥ 18 years and hospitalized for COVID-19 from March 2020 to October 2020. Primary outcomes were acute cardiovascular events (ST elevation myocardial infarction (STEMI), type 1 non-ST elevation myocardial infarction (NSTEMI), acute congestive heart failure (CHF), and acute stroke) and death. Secondary outcomes were respiratory failure, need for mechanical ventilation, and acute deep vein thrombosis (DVT)/pulmonary embolism (PE). Results: Of 376 patients hospitalized for COVID-19, 128 were taking aspirin. Significant proportions of native Americans were hospitalized for COVID-19 in both aspirin (22.7%) and non-aspirin (24.6%) groups. Between aspirin and non-aspirin groups, no significant differences were found with regard to mechanical ventilator support (21.1% vs. 15.3%, P = 0.16), acute cardiovascular events (7.8% vs. 5.2%, P = 0.32), acute DVT/PE (3.9% vs. 5.2%, P = 0.9), readmission rate (13.3% vs. 12.9%, P = 0.91) and mortality (23.4% vs. 20.2%, P = 0.5); however, the median duration of mechanical ventilation was significantly shorter (7 vs. 9 days, P = 0.04) and median length of hospitalization was significantly longer (5.5 vs. 4 days, P = 0.01) in aspirin group compared to non-aspirin group. Conclusion: No significant differences were found in acute cardiovascular events, acute DVT/PE, mechanical ventilator support, and mortality rate between hospitalized COVID-19 patients who were taking aspirin compared to those not taking aspirin. However, larger studies are required to confirm our findings.

Liberation from Mechanical Ventilation in Critically Ill Patients: Korean Society of Critical Care Medicine Clinical Practice Guidelines.

BACKGROUND: Successful liberation from mechanical ventilation is one of the most crucial processes in critical care because it is the first step by which a respiratory failure patient begins to transition out of the intensive care unit and return to their own life. Therefore, when devising appropriate strategies for removing mechanical ventilation, it is essential to consider not only the individual experiences of healthcare professionals, but also scientific and systematic approaches. Recently, numerous studies have investigated methods and tools for identifying when mechanically ventilated patients are ready to breathe on their own. The Korean Society of Critical Care Medicine therefore provides these recommendations to clinicians about liberation from the ventilator. METHOD: Meta-analyses and comprehensive syntheses were used to thoroughly review, compile, and summarize the complete body of relevant evidence. All studies were meticulously assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) method, and the outcomes were presented succinctly as evidence profiles. Those evidence syntheses were discussed by a multidisciplinary committee of experts in mechanical ventilation, who then developed and approved recommendations. RESULT: Recommendations for nine population, intervention, comparator, outcome (PICO) questions about ventilator liberation are presented in this document. This guideline includes seven conditional recommendations, one expert consensus recommendation, and one conditional deferred recommendation. CONCLUSIONS: We developed these clinical guidelines for mechanical ventilation liberation to provide meaningful recommendations. These guidelines reflect the best treatment for patients seeking liberation from mechanical ventilation.

Determination of predisposing factors for prolonged intensive care in patients with exacerbation of chronic obstructive pulmonary disease.

Objectives: To determine the predisposing factors for lengthy intensive care unit stay of chronic obstructive pulmonary disease patients with acute exacerbation. METHODS: The retrospective study was conducted after approval from the ethics review committee of Atatürk Sanatorium Training and Research Hospital, Turkey, and comprised data from January 1, 2017, to August 31, 2022, related to acute exacerbation chronic obstructive pulmonary disease patients receiving intensive care unit treatment. Demographics, comorbidities, treatment, length of stay in hospital and in intensive care unit, and nutritional status were evaluated. Data of patients who spent <10 days in intensive care unit formed Group 1, while those having spent 10 days or more formed Group 2 for comparison purposes. Data was analysed using SPSS 22. RESULTS: Of the 460 patients, 366(79.6%) were in Group 1; 224(61.2%) males and 64(38.8%) females with mean age 70.81±11.57 years. There were 94(20.4%) patients in Group 2; 62(66%) males and 32(34%) females with mean age 72.38±10.88 years (p>0.05). Inotropic agent support, need for haemodialysis, timeframe of invasive mechanical ventilation, length of stay in hospital, 1-month mortality, antibiotic use, use of diuretic agent, acute physiology and chronic health evaluation-ii score, nutrition risk in the critically ill score, history of lung malignancy, and pneumonic infiltration on chest radiograph were significantly more frequenttly observed in Group 2 patients (p<0.05). Age, timeframe of invasive mechanical ventilation, and length of stay in hospital were the factors prolonging intensive care unit stay (p<0.05). CONCLUSIONS: Higher age, longer invasive mechanical ventilation timeframe and hospital stay with acute exacerbation chronic obstructive pulmonary disease caused a prolonged stay in intensive care unit.

Optimized lung expansion ventilation modulates ventilation-induced lung injury in preterm lambs.

INTRODUCTION: Preterm infants close to viability commonly require mechanical ventilation (MV) for respiratory distress syndrome. Despite commonly used lung-sparing ventilation techniques, rapid lung expansion during MV induces lung injury, a risk factor for bronchopulmonary dysplasia. This study investigates whether ventilation with optimized lung expansion is feasible and whether it can further minimize lung injury. Therefore, optimized lung expansion ventilation (OLEV) was compared to conventional volume targeted ventilation. METHODS: Twenty preterm lambs were surgically delivered after 132 days of gestation. Nine animals were randomized to receive OLEV for 24 h, and seven received standard MV. Four unventilated animals served as controls (NV). Lungs were sampled for histological analysis at the end of the experimental period. RESULTS: Ventilation with OLEV was feasible, resulting in a significantly higher mean ventilation pressure (0.7-1.3 mbar). Temporary differences in oxygenation between OLEV and MV did not reach clinically relevant levels. Ventilation in general tended to result in higher lung injury scores compared to NV, without differences between OLEV and MV. While pro-inflammatory tumor necrosis factor-α messenger RNA (mRNA) levels increased in both ventilation groups compared to NV, only animals in the MV group showed a higher number of CD45-positive cells in the lung. In contrast, mean (standard deviations) surfactant protein-B mRNA levels were significantly lower in OLEV, 0.63 (0.38) compared to NV 1.03 (0.32) (p = .023, one-way analysis of variance). CONCLUSION: In conclusion, a small reduction in pulmonary inflammation after 24 h of support with OLEV suggests potential to reduce preterm lung injury.

A machine-learning regional clustering approach to understand ventilator-induced lung injury: a proof-of-concept experimental study.

BACKGROUND: The spatiotemporal progression and patterns of tissue deformation in ventilator-induced lung injury (VILI) remain understudied. Our aim was to identify lung clusters based on their regional mechanical behavior over space and time in lungs subjected to VILI using machine-learning techniques. RESULTS: Ten anesthetized pigs (27 ± 2 kg) were studied. Eight subjects were analyzed. End-inspiratory and end-expiratory lung computed tomography scans were performed at the beginning and after 12 h of one-hit VILI model. Regional image-based biomechanical analysis was used to determine end-expiratory aeration, tidal recruitment, and volumetric strain for both early and late stages. Clustering analysis was performed using principal component analysis and K-Means algorithms. We identified three different clusters of lung tissue: Stable, Recruitable Unstable, and Non-Recruitable Unstable. End-expiratory aeration, tidal recruitment, and volumetric strain were significantly different between clusters at early stage. At late stage, we found a step loss of end-expiratory aeration among clusters, lowest in Stable, followed by Unstable Recruitable, and highest in the Unstable Non-Recruitable cluster. Volumetric strain remaining unchanged in the Stable cluster, with slight increases in the Recruitable cluster, and strong reduction in the Unstable Non-Recruitable cluster. CONCLUSIONS: VILI is a regional and dynamic phenomenon. Using unbiased machine-learning techniques we can identify the coexistence of three functional lung tissue compartments with different spatiotemporal regional biomechanical behavior.

Process of Withdrawal of Mechanical Ventilation at End of Life in the ICU: Clinician Perceptions.

BACKGROUND: Nearly one-quarter of all Americans die in the ICU. Many of their deaths are anticipated and occur following the withdrawal of mechanical ventilation (WMV). However, there are few data on which to base best practices for interdisciplinary ICU teams to conduct WMV. RESEARCH QUESTION: What are the perceptions of current WMV practices among ICU clinicians, and what are their opinions of processes that might improve the practice of WMV at end of life in the ICU? STUDY DESIGN AND METHODS: This prospective two-center observational study conducted in Boston, Massachusetts, the Observational Study of the Withdrawal of Mechanical Ventilation (OBSERVE-WMV) was designed to better understand the perspectives of clinicians and experience of patients undergoing WMV. This report focuses on analyses of qualitative data obtained from in-person surveys administered to the ICU clinicians (nurses, respiratory therapists, and physicians) caring for these patients. Surveys assessed a broad range of clinician perspectives on planning, as well as the key processes required for WMV. This analysis used independent open, inductive coding of responses to open-ended questions. Initial codes were reconciled iteratively and then organized and interpreted using a thematic analysis approach. Opinions were assessed on how WMV could be improved for individual patients and the ICU as a whole. RESULTS: Among 456 eligible clinicians, 312 in-person surveys were completed by clinicians caring for 152 patients who underwent WMV. Qualitative analyses identified two main themes characterizing high-quality WMV processes: (1) good communication (eg, mutual understanding of family preferences) between the ICU team and family; and (2) medical management (eg, planning, availability of ICU team) that minimizes patient distress. Team member support was identified as an essential process component in both themes. INTERPRETATION: Clinician perceptions of the appropriateness or success of WMV prioritize the quality of team and family communication and patient symptom management. Both are modifiable targets of interventions aimed at optimizing overall WMV.

Impact of the COVID-19 pandemic on mechanical ventilation cases and mortality rates in non-SARS-CoV-2 patients: A nationwide analysis in Spain.

BACKGROUND: The COVID-19 pandemic has presented unprecedented challenges for healthcare systems globally, impacting critical care resources and patient outcomes. Understanding its multifaceted effects is crucial for future crisis response. OBJECTIVE: Analyze the repercussions of the COVID-19 pandemic on mechanical ventilation cases and mortality among non-SARS-CoV-2 patients. METHODS: A nationwide database encompassing all patients receiving mechanical ventilation in Spain was used to compare the number of cases and clinical outcomes during COVID-19 (March 2020 - December 2021) to pre-pandemic cases (May 2018 - February 2020). Univariate and multivariate analyses were employed. RESULTS: COVID-19 significantly reduced access to ventilation for non-COVID-19 patients. A 16 % decrease (12,099 fewer patients) was observed during the pandemic compared to pre-pandemic times. This reduction affected all analyzed conditions except self-inflicted injuries, coinciding with a rise in overall mortality risk (34.5% vs 35.6 %, OR 1.09, 95 %CI 1.06-1.12). The increased mortality was consistent across diverse admission types, including cancer (37.1% vs. 41.5 %, OR 1.18, 95 %CI 1.09-1.29), hemorrhagic strokes (55.4% vs. 56.6 %, OR 1.07, 95 %CI 1.02-1.20), acute myocardial infarction (35.6% vs. 38 %, OR 1.11, 95 %CI 1.01-1.21), non-SARS-CoV-2 pneumonia (44.5% vs. 45.8 %, OR 1.12, 95 %CI 1.02-1.24), septic shock (54.7% vs. 56.3 %, OR 1.10, 95 %CI 1.06-1.15), and prolonged ventilation (≥96 h) (37% vs. 38.2 %, OR 1.10, 95 %CI 1.06-1.10). CONCLUSIONS: The findings underscore the profound impact of the COVID-19 pandemic on critical care utilization and patient outcomes among non-SARS-CoV-2 patients. As healthcare systems strive to mitigate future crises, these insights emphasize adaptable strategies for equitable access to life-saving treatments.

Resilience and quality of life in patients who underwent mechanical ventilation due to COVID-19, one year after discharge: a cross-sectional study.

BACKGROUND: Patients with COVID-19 often experience severe long-term sequelae. This study aimed to assess resilience and Quality of Life (QoL) of patients who underwent mechanical ventilation due to COVID-19, one year after discharge. METHODS: This cross-sectional study enrolled patients who received mechanical ventilation for severe COVID-19 and were assessed one-year post-discharge. Participants completed a structured questionnaire via telephone comprising the Connor-Davidson Resilience Scale (CD-RISC) and the Post-COVID-19 Functional Status scale (PCFS). To establish the association between QoL and resilience, Spearman correlations were calculated between the PCFS and the CD-RISC. Linear regression models were adjusted to evaluate which factors were associated with QoL, with the total score of PCFS as the dependent variable. RESULTS: A total of 225 patients were included in the analysis. The CD-RISC had a median score of 83 (IQR 74-91). The PCFS results showed that 61.3% (n = 138) of the patients were able to resume their daily activities without limitations. Among them, 37.3% (n = 84) were classified as Grade 0 and 24% (n = 54) as Grade 1. Mild and moderate functional limitations were found in 33.7% of the patients, with 24.8% (n = 56) classified as Grade 2 and 8.8% (n = 20) as Grade 3. Severe functional limitations (Grade 4) were observed in 4.8% (n = 11) of the patients. High CD-RISC scores were associated with lower levels of PCFS score (p < 0.001). CONCLUSIONS: In this cohort of critically ill patients who underwent mechanical ventilation due to COVID-19, 38% of patients experienced a significant decline in their QoL one year after hospital discharge. Finally, a high level of resilience was strongly associated with better QoL one year after discharge.

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.

[EXTUBATION FAILURE IN BURNS: INCIDENCE, RISK FACTORS AND PROGNOSIS]. / ÉCHEC D'EXTUBATION CHEZ LES BRÛLÉS: INCIDENCE, FACTEURS DE RISQUE ET PRONOSTIC.

The incidence of extubation failure varies between 2 and 25% depending on the studied population. Few studies have been conducted in burn victims. To determine the incidence, causes, risk factors and outcome of burned patients after a failed extubation, a retrospective single-center case-control study was conducted over a period of 3 years (January 2018-December 2021). All burned patients aged over 16, ventilated for at least 24 hours and having had at least one extubation attempt were included. Extubation failure was defined as the need for re-intubation within 48 hours. Eighty-eight patients had planned extubation. These patients were divided into 2 groups comparable in terms of age and sex. Failure group: including patients with failed extubation (N= 34) and a success group (N= 64) including patients who succeeded. The incidence of extubation failure was 36.6%. Hypophosphatemia, anemia <8g/dl, duration of mechanical ventilation of 8,5 days and abundant secretions during extubation were identified as risk factors for extubation failure (p<0.05). The main cause of failure was retention of secretion (50%). Extubation failure was associated with prolonged length of stay (34 vs. 19 days, P= 0.005), increased infectious complications (P=0.007) and mortality rate (79.4%, 1.5%, P<0.001).

Analysis of risk factors for weaning failure from mechanical ventilation in critically ill older patients with coronavirus disease 2019.

Objective: This study aimed to investigate the factors influencing weaning failure from invasive mechanical ventilation (IMV) in critically ill older patients with coronavirus disease 2019 (COVID-19). Methods: We enrolled critically ill older patients with COVID-19 who were admitted to the medical intensive care unit (ICU) and received IMV between December 2022 and June 2023. Results: We included 68 critically ill older patients with COVID-19 (52 male [76.5 %] and 16 female individuals [23.5 %]). The patients' median age (interquartile range) was 75.5 (70.3-82.8) years. The median length of ICU stay was 11.5 (7.0-17.8) days; 34 cases (50.0 %) were successfully weaned from IMV. The successfully weaned group had a higher proportion of underlying chronic obstructive pulmonary disease [6 (17.6 %) vs. 0, P = 0.033] and fewer cases of diabetes [7 (20.6 %) vs. 16 (47.1 %), P = 0.021] compared with the weaning failure group. Serum lactate levels [1.5 (1.2-2.3) vs. 2.6 (1.9-3.1) mmol/L, P < 0.001], blood urea nitrogen [8.2 (6.3-14.4) vs. 11.4 (8.0-21.3) mmol/L, P = 0.033], Acute Physiology and Chronic Health Evaluation (APACHE) II score [19.0 (12.0-23.3) vs. 22.5 (16.0-29.3), P = 0.014], and hospitalization days before endotracheal intubation [1.0 (0.0-5.0) vs. 3.0 (0.0-11.0), P = 0.023] were significantly decreased in the successfully weaned group, whereas PaO2/FiO2 [148.3 (94.6-200.3) vs. 101.1 (67.0-165.1), P = 0.038] and blood lymphocyte levels [0.6 (0.4-1.0) vs. 0.5 (0.2-0.6) 109/L, P = 0.048] were significantly increased, compared with the weaning failure group. Multivariate logistic regression analysis showed that diabetes (OR= 3.413, 95 %CI 1.029-11.326), P = 0.045), APACHE II Score (OR = 1.089, 95 % CI 1.008-1.175), P = 0.030), and hospitalization days before endotracheal intubation (OR = 1.137, 95 % CI 1.023-1.264), P = 0.017) were independent risk factors for weaning failure. Conclusion: In critically ill older patients with COVID-19 with diabetes, higher APACHE II Score, and longer hospitalization days before endotracheal intubation, weaning from IMV was more challenging. The study could help develop strategies for improving COVID-19 treatment.

Biopsy-Proven Gastric Pathological Findings in Mechanically Ventilated Intensive Care Unit Patients.

Objectives Helicobacter pylori (H. pylori) is known to affect a large proportion of the world population. It plays a role in the pathogenesis of peptic ulcer (PU) and increases the likelihood of bleeding. In critically ill patients in intensive care units (ICUs), the risk of bleeding may be much higher due to many concomitant factors. The study aimed to determine the activation of H. pylori in mechanically ventilated (MV) intensive care patients and compare this with the general population. Methods This study was performed retrospectively by screening patients who underwent esophagogastroduodenoscopy and histopathological sampling in our hospital between January and June 2023. The study included 79 patients aged between 18 and 85 years. The patients were categorized into two groups: 35 patients in the ICU with mechanical ventilation (MV) support (EMV) and 44 patients who presented to the gastroenterology department due to dyspeptic symptoms and underwent endoscopy (ED). Age; sex characteristics; laboratory parameters such as hemoglobin (Hb), hematocrit (Htc), mean cellular volume (MCV), white blood cell (WBC), neutrophil, platelet, glucose, urea, creatinine, aspartate transaminase (AST), alanine transaminase (ALT), C-reactive protein (CRP), albumin, ferritin, thyroid-stimulating hormone (TSH), anti-hepatitis C virus (HCV), hepatitis B surface antigen (HBsAg), anti-HIV; and biopsy results (H. pylori positivity, intestinal metaplasia, and atrophy) were recorded. Results A total of 79 patients who underwent gastric biopsy were assessed. There were 35 patients in the EMV group and 44 patients in the ED group. There was no difference in gender and age distribution between the groups. Hb and Htc were significantly lower in EMV compared to ED (p=0.001). Hb was 9.4±1.7 g/dL in EMV and 10.8±2.1 g/dL in ED. Htc was 29.6±5.1 in EMV and 33.5±5.7 in ED. MCV, WBC, glucose, urea, AST, ALT, CRP, and ferritin values were statistically significantly higher in EMV (p<0.05). Albumin and creatinine levels were statistically significantly lower in EMV (p<0.05). There was no significant difference between the groups in terms of neutrophils, platelets, and TSH. In the EMV group, H. pylori activity was negative in 31 (88.6%) patients and positive in four (11.4%) patients. In the ED group, H. pylori activity was negative in 30 (68.2%) patients and positive in 14 (31.8%) patients. There was a statistically significant difference between the groups in terms of H. pylori positivity (p=0.032). Conclusions The prevalence of H. pylori in MV patients in the ICU is low compared to the average population. The incidence of atrophic gastritis and intestinal metaplasia is the same. The present study supports that ICU cases do not have a higher risk of gastric premalignant lesions compared to the average population.

Development of a New Method for Evaluating Heat-and-Moisture Exchanger Performance.

BACKGROUND: A model system described in International Organization for Standardization 9360 is the standard method for estimating the humidifying performance of heat-and-moisture exchangers (HMEs). However, there are no reliable bedside methods for evaluating the ongoing humidification performance of HMEs. Therefore, this study aimed to develop 2 clinically applicable methods for estimating the ongoing humidifying performance of HMEs and to evaluate their reliability in a model system. METHODS: Physiologically expired gas was simulated using a heated humidifier, and ventilation was delivered using a ventilator with constant flow through 3 different types of HMEs. Relative humidity (RH) was measured using a capacitive-type moisture sensor. Water content lost during expiration was calculated by integrating absolute humidity (AH), instantaneous gas flow measured at the expiratory outlet of the ventilator, and time. We also calculated the water content released and captured by the HMEs during tidal ventilation by integrating the difference in AH across the HMEs, instantaneous gas flow, and time. RESULTS: We found that the RH, temperature, and AH were almost constant on the expiratory outlet of the ventilator but rapidly varied near the HMEs. The water content lost by the 3 HMEs was associated with the manufacturer-reported values and inversely correlated with the calculated values of the water content exchanged by the HMEs. The water content released and captured by HMEs was closely correlated with the difference in HME weight measured at the end of inspiration and expiration; however, the water content captured by HMEs seemed to be overestimated. CONCLUSIONS: Our results demonstrated that our system was able to detect the differences in the performance of 3 models of HMEs and suggest that our method for calculating water loss is reliable for estimating the water retention performance of HMEs during mechanical ventilation, even in the presence of a constant flow.

Recruitment-to-inflation ratio reflects the impact of peep on dynamic lung strain in a highly recruitable model of ARDS.

BACKGROUND: The recruitment-to-inflation ratio (R/I) has been recently proposed to bedside assess response to PEEP. The impact of PEEP on ventilator-induced lung injury depends on the extent of dynamic strain reduction. We hypothesized that R/I may reflect the potential for lung recruitment (i.e. recruitability) and, consequently, estimate the impact of PEEP on dynamic lung strain, both assessed through computed tomography scan. METHODS: Fourteen lung-damaged pigs (lipopolysaccharide infusion) underwent ventilation at low (5 cmH2O) and high PEEP (i.e., PEEP generating a plateau pressure of 28-30 cmH2O). R/I was measured through a one-breath derecruitment maneuver from high to low PEEP. PEEP-induced changes in dynamic lung strain, difference in nonaerated lung tissue weight (tissue recruitment) and amount of gas entering previously nonaerated lung units (gas recruitment) were assessed through computed tomography scan. Tissue and gas recruitment were normalized to the weight and gas volume of previously ventilated lung areas at low PEEP (normalized-tissue recruitment and normalized-gas recruitment, respectively). RESULTS: Between high (median [interquartile range] 20 cmH2O [18-21]) and low PEEP, median R/I was 1.08 [0.88-1.82], indicating high lung recruitability. Compared to low PEEP, tissue and gas recruitment at high PEEP were 246 g [182-288] and 385 ml [318-668], respectively. R/I was linearly related to normalized-gas recruitment (r = 0.90; [95% CI 0.71 to 0.97) and normalized-tissue recruitment (r = 0.69; [95% CI 0.25 to 0.89]). Dynamic lung strain was 0.37 [0.29-0.44] at high PEEP and 0.59 [0.46-0.80] at low PEEP (p < 0.001). R/I was significantly related to PEEP-induced reduction in dynamic (r = - 0.93; [95% CI - 0.78 to - 0.98]) and global lung strain (r = - 0.57; [95% CI - 0.05 to - 0.84]). No correlation was found between R/I and and PEEP-induced changes in static lung strain (r = 0.34; [95% CI - 0.23 to 0.74]). CONCLUSIONS: In a highly recruitable ARDS model, R/I reflects the potential for lung recruitment and well estimates the extent of PEEP-induced reduction in dynamic lung strain.