Development and prospective validation of a model for predicting weaning in chronic ventilator dependent patients

Application of improved Glasgow coma scale score as switching point for sequential invasive-noninvasive mechanical ventilation on chronic obstructive pulmonary disease (COPD) with respiratory failure

BACKGROUND

To compare the efficacy and feasibility of using a modified Glasgow coma scale (GCS) score of 13 or 15 as the criterion for switching chronic obstructive pulmonary disease (COPD) patients with respiratory failure to sequential invasive-noninvasive ventilation.

METHODS

COPD patients with respiratory failure who had undergone endotracheal intubation and invasive mechanical ventilation (IMV) between June 2017 and June 2020 at 4 different hospitals in China were included. A total of 296 patients were randomly divided into 2 groups. In group A, the patients were extubated and immediately placed on noninvasive ventilation (NIV) when the modified GCS score reached 13. In group B, the same was done when the modified GCS score reached 15.

RESULTS

No significant differences in the mean blood pressure, oxygenation index, arterial partial pressure of oxygen, and arterial partial pressure of carbon dioxide were seen between groups A and B before extubation and 3 hours after NIV. The re-intubation times were also similar in the 2 groups. Compared to group B, the length of hospital stay, incidence of ventilator associated pneumonia, and time of invasive ventilation were all significantly lower in group A (P = .041, .001, <.001).

CONCLUSION

Using a modified GCS score of 13 as the criterion for switching from IMV to NIV can significantly reduce the duration of IMV, length of hospital stay, and incidence of ventilator associated pneumonia in COPD patients with respiratory failure.

A Simple Weaning Model Based on Interpretable Machine Learning Algorithm for Patients With Sepsis: A Research of MIMIC-IV and eICU Databases

Background

Invasive mechanical ventilation plays an important role in the prognosis of patients with sepsis. However, there are, currently, no tools specifically designed to assess weaning from invasive mechanical ventilation in patients with sepsis. The aim of our study was to develop a practical model to predict weaning in patients with sepsis.

Methods

We extracted patient information from the Medical Information Mart for Intensive Care Database-IV (MIMIC-IV) and the eICU Collaborative Research Database (eICU-CRD). Kaplan–Meier curves were plotted to compare the 28-day mortality between patients who successfully weaned and those who failed to wean. Subsequently, MIMIC-IV was divided into a training set and an internal verification set, and the eICU-CRD was designated as the external verification set. We selected the best model to simplify the internal and external validation sets based on the performance of the model.

Results

A total of 5020 and 7081 sepsis patients with invasive mechanical ventilation in MIMIC-IV and eICU-CRD were included, respectively. After matching, weaning was independently associated with 28-day mortality and length of ICU stay (p &lt; 0.001 and p = 0.002, respectively). After comparison, 35 clinical variables were extracted to build weaning models. XGBoost performed the best discrimination among the models in the internal and external validation sets (AUROC: 0.80 and 0.86, respectively). Finally, a simplified model was developed based on XGBoost, which included only four variables. The simplified model also had good predictive performance (AUROC:0.75 and 0.78 in internal and external validation sets, respectively) and was developed into a web-based tool for further review.

Conclusions

Weaning success is independently related to short-term mortality in patients with sepsis. The simplified model based on the XGBoost algorithm provides good predictive performance and great clinical applicablity for weaning, and a web-based tool was developed for better clinical application.

Use of the modified Glasgow Coma Scale score to guide sequential invasive-noninvasive mechanical ventilation weaning in patients with AECOPD and respiratory failure

Sequential invasive-noninvasive ventilation (NIV) improves the outcomes of patients with respiratory failure caused by acute exacerbation of chronic obstructive pulmonary disease (AECOPD); however, there is no clear consensus on the optimal timing of the switch to sequential invasive-NIV in these patients. In the present study, a potential role for the modified Glasgow Coma Scale (GCS) score to guide sequential weaning was investigated. Patients with AECOPD and respiratory failure were prospectively recruited from three study centers (Wenling Hospital Affiliated to Wenzhou Medical University, the First Affiliated Hospital of Wenzhou Medical University and Changsha Central Hospital) between January 1st 2016 and December 31st 2018. Patients were randomly assigned to group A and B, with the switching point for sequential weaning strategy in the two groups being a modified GCS score ≥13 and 10 points, respectively. Each group included 240 patients. Baseline demographic characteristics were comparable in the two groups. The duration of invasive mechanical ventilation (IMV) in group A was significantly shorter than that in group B. However, there were no significant between-group differences with respect to the incidence of re-intubation, ventilator-associated pneumonia, in-hospital mortality or the length of hospital stay. Use of a modified GCS score ≥13 as the switching point for sequential invasive-NIV may help decrease the duration of IMV in patients with AECOPD and respiratory failure.

Variables predicting weaning outcome in prolonged mechanically ventilated tracheotomized patients: a retrospective study

Background

Several studies have assessed predictors of weaning and extubation outcome in short-term mechanically ventilated patients, but there are only few studies on predictors of weaning from prolonged mechanical ventilation.

Methods

Retrospective, single-center, observational study at a specialized national weaning center in Germany. Patients’ medical records were reviewed to obtain data on demographics, comorbidities, respiratory indices, and the result of a prospectively documented, standardized spontaneous breathing trial (SBT) upon admission to the weaning center. Respiratory indices assessed were the ventilatory ratio (VR) and parameters derived from calculated mechanical power (MP). Predictors associated with failure of prolonged weaning and failure of the SBT were assessed using a binary logistic regression model.

Results

A total of 263 prolonged mechanically ventilated, tracheotomized patients, treated over a 5-year period were analyzed. After 3 weeks of mechanical ventilation, patients with unsuccessful weaning failed a SBT more frequently and showed significantly increased values for inspiratory positive airway pressure, driving pressure, VR, absolute MP, and MP normalized to predicted body weight and dynamic lung-thorax compliance (LTC-MP). In the logistic regression analyses, variables independently correlated with weaning failure were female gender (adjusted odds ratio 0.532 [95% CI 0.291–0.973]; p = 0.040), obesity (body mass index ≥ 30 kg/m²) (2.595 [1.210–5.562]; p = 0.014), COPD (3.209 [1.563–6.589]; p = 0.002), LTC-MP (3.470 [1.067–11.284]; p = 0.039), P_aCO₂ on mechanical ventilation (1.101 [95% CI 1.034–1.173]; p = 0.003), and failure of the SBT (4.702 [2.250–9.825]; p < 0.001). In addition, female gender (0.401 [0.216–0.745]; p = 0.004), LTC-MP (3.017 [1.027–8.862]; p = 0.046), and P_aCO₂ on mechanical ventilation (1.157 [1.083–1.235]; p < 0.001) were independent risk factors for an unsuccessful SBT.

Conclusions

In the present study, the derived predictors of weaning point to a crucial role of the workload imposed on respiratory muscles during spontaneous breathing. Mechanical power normalized to lung-thorax compliance was independently correlated with weaning outcome and may identify patients at high risk for weaning failure.

Mechanical ventilation in the emergency department for 24 hours or longer is associated with delayed weaning

PURPOSE

We examined various aspects of critical care to identify factors in the emergency department (ED) that affected the overall duration of mechanical ventilation (MV). We specifically focused on whether 24 hours of ED MV affected the weaning success and the duration of MV.

MATERIALS AND METHODS

Mechanical ventilation cases that started in the ED because of purely respiratory problems were enrolled in the retrospective cohort. We recorded demographic data, duration of MV in ED, various severity scores, previously known factors of prolonged MV, and achievement of ventilator weaning. All the significant factors in univariate survival analyses were included in a multivariate analysis.

RESULTS

The estimated median of the entire duration of MV was longer in patients who received 24 hours or more of MV in ED compared with that of patients who received MV for less than 24 hours (33.0 vs 15.4 days, P = .003). Mechanical ventilation for longer than 24 hours in the ED remained a significant factor that prolonged the entire MV duration in the multivariate analysis (hazard ratio, 0.577; P = .019). Hypoalbuminemia and abbreviated mortality in ED sepsis (MEDS) score were also independently correlated (P ≤ .001 for both).

CONCLUSIONS

Mechanical ventilation in the ED for 24 hours or longer is associated with delayed ventilator weaning.

Epidemiology of ventilator-associated pneumonia in a long-term acute care hospital

OBJECTIVE

To characterize the epidemiology and microbiology of ventilator-associated pneumonia (VAP) in a long-term acute care hospital (LTACH).

DESIGN

Retrospective study of prospectively identified cases of VAP.

SETTING

Single-center, 207-bed LTACH with the capacity to house 42 patients requiring mechanical ventilation, evaluated from April 1, 2006, through January 31, 2008.

METHODS

Data on the occurrence of VAP were collected prospectively as part of routine infection surveillance at Radius Specialty Hospital. After March 2006, Radius Specialty Hospital implemented a bundle of interventions for the prevention of VAP (hereafter referred to as the VAP-bundle approach). A case of VAP was defined as a patient who required mechanical ventilation at Radius Specialty Hospital for at least 48 hours before any symptoms of pneumonia appeared and who met the Centers for Disease Control and Prevention criteria for VAP. Sputum samples were collected from a tracheal aspirate if there was clinical suspicion of VAP, and these samples were semiquantitatively cultured.

RESULTS

During the 22-month study period, 23 cases of VAP involving 19 patients were associated with 157 LTACH admissions (infection rate, 14.6%), corresponding to a rate of 1.67 cases per 1,000 ventilator-days, which is a 56% reduction from the VAP rate of 3.8 cases per 1,000 ventilator-days reported before the implementation of the VAP-bundle approach (P< .001). Microbiological data were available for 21 (91%) of 23 cases of VAP. Cases of VAP in the LTACH were frequently polymicrobial (mean number +/- SD, 1.78+/-1.0 pathogens per case of VAP), and 20 (95%) of 21 cases of VAP had at least 1 pathogen (Pseudomonas species, Acinetobacter species, gram-negative bacilli resistant to more than 3 antibiotics, or methicillin-resistant Staphylococcus aureus) cultured from a sputum sample. LTACH patients with VAP were more likely to have a neurological reason for ventilator dependence, compared with LTACH patients without VAP (69.6% of cases of VAP vs 39% of cases of respiratory failure; P= .014). In addition, patients with VAP had a longer length of LTACH stay, compared with patients without VAP (median length of stay, 131 days vs 39 days; P= .002). In 6 (26%) of 23 cases of VAP, the patient was eventually weaned from use of mechanical ventilation. Of the 19 patients with VAP, 1 (5%) did not survive the LTACH stay.

CONCLUSIONS

The VAP rate in the LTACH is lower than the VAP rate reported in acute care hospitals. Cases of VAP in the LTACH were frequently polymicrobial and were associated with multidrug-resistant pathogens and increased length of stay. The guidelines from the Centers for Disease Control and Prevention that are aimed at reducing cases of VAP appear to be effective if applied in the LTACH setting.

Successful weaning predictors in a respiratory care center in Taiwan

Respiratory care centers (RCCs) provide effective care for patients who have been in intensive care and have undergone prolonged mechanical ventilation. Between February 2002 and December 2005, 891 patients who met the admission criteria of RCCs were referred to our RCC at Kaohsiung Medical University Hospital in southern Taiwan for attempted weaning. We recorded demographic and clinical data, including variables identified previously as predictive of weaning success among highly selected populations. The common causes of respiratory failure at RCC admission were neuromuscular disease (29.2%), pneumonia (27.5%), cancer (18.0%), cardiovascular disease (10.1%), sepsis (5.7%) and post-surgery (1.6%). The percentage of patients successfully weaned was 40.2%, while 59.8% remained dependent on ventilators. In a stepwise multivariate logistic regression analysis, significant predictors of weaning success included neuromuscular disease (odds ratio [OR], 2.64), APACHE II score (OR, 0.93) and blood urea nitrogen level at RCC admission (OR, 0.99). The results could be helpful in the accreditation of medical care quality and may provide guidelines for future research and education programs.

Management of patients requiring prolonged mechanical ventilation: report of a NAMDRC consensus conference

Patients requiring prolonged mechanical ventilation (PMV) are rapidly increasing in number, as improved ICU care has resulted in many patients surviving acute respiratory failure only to then require prolonged mechanical ventilatory assistance during convalescence. This patient population has clearly different needs and resource consumption patterns than patients in acute ICUs, and specialized venues, management strategies, and reimbursement schemes for them are rapidly emerging. To address these issues in a comprehensive way, a conference on the epidemiology, care, and overall management of patients requiring PMV was held. The goal was to not only review existing practices but to also develop recommendations on a variety of assessment, management, and reimbursement issues associated with patients requiring PMV. Formal presentations were made on a variety of topics, and writing groups were formed to address three specific areas: epidemiology and outcomes, management and care settings, and reimbursement. Each group was charged with summarizing current data and practice along with formulation of recommendations. A working draft of the products of these three groups was then created and circulated among all participants. The document was reworked with input from all concerned until a final product with consensus recommendations on 12 specific issues was achieved.