Assisted Ventilation Research Articles

Severity of Exacerbation in Pneumococcal Vaccinated versus Unvaccinated Patients with Exacerbation of Chronic Obstructive Pulmonary Disease: A Post hoc Analysis of Presentation Status of the Subjects of HOPE Chronic Obstructive Pulmonary Disease Study

Background: Acute exacerbations occur with varying frequency and severity and impact the natural course of chronic obstructive pulmonary disease (COPD) patients. Pneumococcal vaccination has been shown to decrease the incidence of community-acquired pneumonia and exacerbation rate in COPD patients. There is a paucity of data on the influence of pneumococcal conjugate vaccination on the severity of COPD exacerbations. Objectives: The objectives of this study were to evaluate the severity of exacerbation in pneumococcal vaccinated (vaccinated with 13-valent conjugate vaccine) versus unvaccinated COPD subjects hospitalized with acute exacerbation. Materials and Methods: This was a post hoc analysis of the severity of exacerbation in the subjects of HOPE COPD study. This involved the collection of clinical, radiological, and laboratory data of 120 COPD patients who were hospitalized with an acute exacerbation, 60 of whom had prior pneumococcal vaccination and 60 were unvaccinated. Data of COPD patients at the time of presentation with acute exacerbation were analyzed. Comparison was made between severity parameters such as presence of fever, leukocytosis, respiratory failure, multilobar consolidation, hypotension needing inotropic support, and presence of sepsis between pneumococcal vaccinated and unvaccinated subjects. Results: The occurrence of multilobar consolidation was substantially less in the vaccinated group (60% vs. 6.7%; P = 0.0001). The incidence of fever, leukocytosis, and elevated C-reactive protein was significantly higher in the unvaccinated group. Need for intensive care unit care was higher in the unvaccinated group (58.3% vs. 30% with P = 0.019). The occurrence of new-onset respiratory failure was similar in both the groups although type 2 failure with respiratory acidosis was more in the unvaccinated group. Patients in the unvaccinated group had a higher incidence of sepsis and need for inotropic support as well as assisted ventilation. Conclusions: Prior immunization with 13-valent pneumococcal conjugate vaccine ameliorates the severity of exacerbation in COPD patients needing hospitalization. Pneumococcal vaccination may be recommended for all patients with COPD who are at risk of hospitalization with acute exacerbation.

Clinical Characteristics of Lung Abscess Caused by Streptococcus Constellatus Infection.

This study aimed to understand the clinical characteristics of pulmonary abscess caused by Streptococcus constellatus infection. The clinical manifestations, laboratory examination, drug sensitivity, chest CT manifestations, and treatment and prognosis of patients with pulmonary abscess caused by Streptococcus constellatus infection were retrospectively collected and analyzed. A total of 9 cases of pulmonary abscess caused by Streptococcus constellatus infection were confirmed; one case was confirmed by traditional cultures, while metagenomic next-generation sequencing (mNGS) confirmed the other 8 cases. All of the 9 patients had different degrees of cough, sputum, fever, chest pain, and/or dyspnea, and the physical examination showed fast breathing, reduced respiratory sound, or moist rales on the affected side. In laboratory tests, 8 patients had elevated white blood cells and hypoproteinemia upon admission. Blood gas analysis showed an oxygenation index < 300. The antimicrobial susceptibility testing results in 1 patient with culture-confirmed pathogen diagnosis showed that Streptococcus constellatus was susceptible to ampicillin, penicillin G, cefotaxime, ceftriaxone, cefepime, meropenem, chloramphenicol, linezolid, levofloxacin, and vancomycin and resistant to tetracycline and clindamycin. Relevant antibiotic resistance genes were not detected by mNGS in the 8 patients with negative culture and positive mNGS results. A chest CT showed lung consolidation or cavity formation in 9 patients admitted to the hospital, and 5 patients had pleural effusion. 3 cases were admitted to the respiratory intensive care unit (RICU) and 6 cases were admitted to the general ward. There were 3 cases of nasal catheter oxygen inhalation, 1 case of mask oxygen inhalation, and 5 cases of non-invasive ventilator assisted ventilation. All patients received penicillin or respiratory quinolones anti-infection therapy, and 3 cases were treated with a thoracic closed drainage tube. All patients were discharged from the hospital after improvement, and the hospital stay was 15 - 23 days. Patients with pulmonary abscess caused by Streptococcus constellatus infection have an urgent condition and rapid progression. It is helpful to use mNGS combined with traditional culture as soon as possible to identify the pathogenic bacteria. Penicillin antibiotics should be the first choice for pulmonary abscess caused by a suspected Streptococcus constellatus infection. If a patient´s condition worsens during the treatment, especially for patients who have lesions involving the interlobar fissure or pleura, compressive atelectasis caused by pleural fluid formation or an increase in the amount of pleural effusion needs to be highly suspected.

Effect analysis of information-guided enteral nutrition-associated diarrhea treatment process in patients with chronic obstructive pulmonary disease undergoing continuous non-invasive assisted ventilation: a mixed cohort study of pre- and post-control

To clarify the application effect of information-guided enteral nutrition-associated diarrhea (ENAD) management process in patients with chronic obstructive pulmonary disease (COPD) undergoing non-invasive assisted ventilation. A mixed cohort study of pre- and post-control was conducted. Thirty-nine patients with COPD who were admitted to the emergency intensive care unit (ICU) of Huzhou First People's Hospital from July 1, 2021 to July 31, 2022 were enrolled. Taking the completion of the software development of ENAD management software for critically ill patients on January 28, 2022 as the time node, 20 patients admitted from July 1, 2021 to January 28, 2022 were set as the control group, and 19 patients admitted from January 29 to July 31, 2022 were set as the observation group. The two groups of patients received the same enteral nutrition support treatment, and the control group implemented the conventional ENAD treatment process with enteral nutrition intolerance disposal process as the core. On the basis of the control group, the observation group implemented the information-guided ENAD treatment process, and the system software actively captured the information of ENAD patients and reminded the medical team to improve the patient's diarrhea-related examination and provide alternative treatment plans. The duration of antidiarrhea, feeding interruption rate, and energy and protein intake, blood biochemical indexes, incidence of abnormal blood electrolyte metabolism, daily continuous non-invasive assisted ventilation and endotracheal intubation after 7 days of targeted diarrhea intervention were compared between the two groups. Except for the basal pulse rate, there were no significant differences in gender distribution, age, and vital signs, basic nutritional status, arterial blood gas analysis and blood biochemistry at admission between the two groups, indicating comparability between the two groups. When ENAD occurred, the patients in the observation group obtained earlier cessation of diarrhea than those in the control group [days: 3.00 (2.00, 3.25) vs. 4.00 (3.00, 5.00), P < 0.01], and the feeding interruption rate was significantly lower than that in the control group [10.53% (2/19) vs. 65.00% (13/20), P < 0.01]. After 7 days of diarrhea intervention, the energy intake of the observation group was significantly higher than that of the control group [kJ×kg-1×d-1: 66.28 (43.34, 70.36) vs. 47.88 (34.60, 52.32), P < 0.01], the levels of hemoglobin (Hb), albumin (Alb) and serum prealbumin (PAB) were significantly higher than those in the control group [Hb (g/L): 119.79±10.04 vs. 110.20±7.75, Alb (g/L): 36.00 (33.75, 37.25) vs. 31.00 (30.00, 33.00), PAB (mg/L): 155.79±25.78 vs. 140.95±14.97, all P < 0.05], the daily continuous non-invasive assisted ventilation duration was significantly shorter than that of the control group [hours: 14 (12, 16) vs. 16 (14, 18), P < 0.01], and the arterial partial pressure of carbon dioxide (PaCO2) was significantly lower than that of the control group [mmHg (1 mmHg ≈ 0.133 kPa): 66.00 (62.00, 70.00) vs. 68.00 (67.50, 70.05), P < 0.05]. However, there were no significant differences in protein intake, incidence of abnormal electrolyte metabolism, and incidence of endotracheal intubation due to acute respiratory failure between the two groups. The information-guided ENAD treatment process can enable the COPD patients undergoing continuous non-invasive assisted ventilation who experience ENAD to receive earlier cessation of diarrhea, and improve the protein energy metabolism and respiratory function of the patients.

Noninvasive mechanical ventilation assistance in amyotrophic lateral sclerosis: a systematic review.

Respiratory failure is the most common cause of death in patients with amyotrophic lateral sclerosis (ALS), and morbidity is related to poor quality of life (QOL). Non-invasive ventilation (NIV) may be associated with prolonged survival and QOL in patients with ALS. To assess whether NIV is effective and safe for patients with ALS in terms of survival and QOL, alerting the health system. Systematic review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting standards using population, intervention, comparison, and outcome strategies. The Cochrane Library, CENTRAL, MEDLINE, LILACS, EMBASE, and CRD databases were searched based on the eligibility criteria for all types of studies on NIV use in patients with ALS published up to January 2022. Data were extracted from the included studies, and the findings were presented using a narrative synthesis. Of the 120 papers identified, only 14 were related to systematic reviews. After thorough reading, only one meta-analysis was considered eligible. In the second stage, 248 studies were included; however, only one systematic review was included. The results demonstrated that NIV provided relief from the symptoms of chronic hypoventilation, increased survival, and improved QOL compared to standard care. These results varied according to clinical phenotype. NIV in patients with ALS improves the outcome and can delay the indication for tracheostomy, reducing expenditure on hospitalization and occupancy of intensive care unit beds. PROSPERO database: CRD42021279910 - https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=279910.

Hypotension in Preterm Newborns and Its Short-Term Outcome: Experience of a Tertiary Care Hospital in Bangladesh

Background: Blood pressure values of too low or too high can be related with serious morbidity and mortality. Neonatal hypotension has been found to be related with serious short term as well as significant long-term health complications. Thus, identifying this low blood pressure in preterm neonates with its impacts on neonatal health is crucial. Objectives: To evaluate blood pressure values in preterm newborn and short-term impacts of hypotension on neonatal health. Methods: This prospective observational study was conducted in Neonatal Intensive Care Unit (NICU) of Bangabandhu Sheikh Mujib Medical University a tertiary care hospital of Dhaka city after approval from Institutional Review Board for a period of one years. Neonates having gestation&lt; 37 completed weeks admitted in NICU of BSMMU were enrolled in the study after getting informed consent from the parents. Proper antenatal and postnatal history were recorded in data collection form. Blood pressure was measured by non-invasive oscillometric method in all neonates within 24 hours after birth by ideal procedure. Blood pressure was monitored at an interval of 12 hours or more frequently when required till discharge or death. Information on neonatal mortality and morbidity were recorded in data collection form. Results: A total of 114 preterm neonates were studied during the study period, among them 61 (53.5%) had normal blood pressure and 53 (46.5%) had hypotension. Among the enrolled patients, 15 (13.2%) patients died, 3 (2.6%) left against medical advice, 11 (9.6%) 96 (84.2%) were discharged with advice. Short time outcomes like culture proven sepsis, use of ionotrops, need for oxygen support and assisted ventilation, feeding intolerance, Necrotizing enterocolitis, intraventricular hemorrhage, retinopathy of prematurity and duration of hospital stay were significantly higher in hypotensive group. Mortality was also higher in hypotensive group than normotensive group (26.4% vs 3.3%, p &lt;0.001). Conclusion: Hypotension in preterm neonates was associated with significant mortality and morbidity in early post-natal period.

The Characteristics and Laboratory Findings of SARS-CoV-2 Infected Patients during the First Three COVID-19 Waves in Portugal-A Retrospective Single-Center Study.

Background and Objectives: Given the wide spectrum of clinical and laboratory manifestations of the coronavirus disease 2019 (COVID-19), it is imperative to identify potential contributing factors to patients' outcomes. However, a limited number of studies have assessed how the different waves affected the progression of the disease, more so in Portugal. Therefore, our main purpose was to study the clinical and laboratory patterns of COVID-19 in an unvaccinated population admitted to the intensive care unit, identifying characteristics associated with death, in each of the first three waves of the pandemic. Materials and Methods: This study included 337 COVID-19 patients admitted to the intensive care unit of a single-center hospital in Lisbon, Portugal, between March 2020 and March 2021. Comparisons were made between three COVID-19 waves, in the second (n = 325) and seventh (n = 216) days after admission, and between discharged and deceased patients. Results: Deceased patients were considerably older (p = 0.021) and needed greater ventilatory assistance (p = 0.023), especially in the first wave. Differences between discharged and deceased patients' biomarkers were minimal in the first wave, on both analyzed days. In the second wave significant differences emerged in troponins, lactate dehydrogenase, procalcitonin, C-reactive protein, and white blood cell subpopulations, as well as platelet-to-lymphocyte and neutrophil-to-lymphocyte ratios (all p < 0.05). Furthermore, in the third wave, platelets and D-dimers were also significantly different between patients' groups (all p < 0.05). From the second to the seventh days, troponins and lactate dehydrogenase showed significant decreases, mainly for discharged patients, while platelet counts increased (all p < 0.01). Lymphocytes significantly increased in discharged patients (all p < 0.05), while white blood cells rose in the second (all p < 0.001) and third (all p < 0.05) waves among deceased patients. Conclusions: This study yields insights into COVID-19 patients' characteristics and mortality-associated biomarkers during Portugal's first three COVID-19 waves, highlighting the importance of considering wave variations in future research due to potential significant outcome differences.

Pendelluft in patients with acute respiratory distress syndrome during trigger and reverse triggering breaths

Pendelluft, the shift of air from non-dependent to dependent lung regions, is known to occur during active breathing in ventilated patients. However, information about pendelluft in ARDS patients under assisted mechanical ventilation is limited. In this prospectively collected and retrospectively analyzed study, we combined electrical impedance tomography and respiratory mechanics monitoring to quantitatively examine pendelluft in trigger and reverse triggering breaths in 20 mechanically ventilated patients with ARDS during the transition from controlled to active breaths under volume-cycled ventilation. Besides the 10 resting breaths in each patient, 20% of the counted active breaths were selected based on three levels of esophageal pressure swing (∆Pes): low (< 5 cm H2O, breaths = 471), moderate (≥ 5, < 10 cm H2O, breaths = 906), and high effort (≥ 10 cm H2O, breaths = 565). The pendelluft response to breathing efforts was significantly greater in trigger breaths than in reverse triggering breaths (p < 0.0001). Based on the pendelluft-∆Pes slope (ml/cmH2O), there were two distinct patterns of effort-related pendelluft (high vs. low pendelluft group). For trigger breaths, the high pendelluft group (n = 9, slope 0.7–2.4 ml/cmH2O) was significantly associated with lower peak airway/plateau pressure and lower respiratory system/lung elastance than the low pendelluft group (n = 11, slope − 0.1 to 0.3 ml/cmH2O). However, there was no difference in respiratory mechanics between high and low pendelluft groups for reverse triggering breathes. The use of ∆Pes to predict pendelluft was found to have a low positive predictive value.

Respiratory Failure in Acute Medical Unit

The huge rise in patients presenting to acute medical units with respiratory failure during covid-19 pandemic has exposed the acute physician to different types of assisted ventilation, which was not implemented frequently before the pandemic. High-flow nasal oxygen and non-invasive ventilation have reduced the need for invasive mechanical ventilation. Shortage in level 3 beds is still an issue, and even after the pandemic, the idea of introducing level 1.5 or enhanced care in acute medical units is evolving, which means that acute physicians are more likely to deal with respiratory failure cases and should be aware of the indications and benefits of these two modalities. The authors discussed in this review the basics of using high-flow and non-invasive ventilation in a straightforward approach.

Off-pump vs. on-pump bypass surgery grafting in diabetic patients with three-vessel disease: a propensity score matching study

BackgroundControversy exists regarding the advantages and risks of off-pump vs. on-pump coronary artery bypass grafting (CABG) for patients with diabetes. We therefore compare the early clinical outcomes of off-pump vs. on-pump procedures for diabetic patients with three-vessel disease.Materials and methodsWe conducted a retrospective analysis of clinical data obtained from 548 diabetic patients with three-vessel coronary artery disease who underwent isolated CABG between January 2016 and June 2020. To adjust the differences of baseline characteristics between the off-pump CABG (OPCAB) and on-pump CABG (ONCAB) groups, propensity score matching (PSM) was used. Following 1:1 matching, we selected 187 pairs of patients for further comparison of outcomes within the first 30 days after surgery.ResultsThe preoperative characteristics of the patients between the two groups were clinically comparable after PSM. The OPCAB group exhibited a significantly higher incidence of incomplete revascularization (27.3% vs. 14.4%; P = 0.002) compared with the ONCAB group. No differences were seen in mortality within 30 days between the matched groups (1.1% vs. 3.7%; P = 0.174). Notably, the OPCAB group had a lower risk of respiratory failure or infection (2.1% vs. 7.0%; P = 0.025), less postoperative stroke (1.1% vs. 4.8%; P = 0.032), and reduced postoperative ventilator assistance time (35.8 ± 33.7 vs. 50.9 ± 64.8; P = 0.005).ConclusionOPCAB in diabetic patients with three-vessel disease is a safe procedure with reduced early stroke and respiratory complications and similar mortality rate, myocardial infarction, and renal failure requiring dialysis to conventional on-pump revascularization.

Noninvasive Neurally Adjusted Ventilatory Assist in Infants With Bronchiolitis: Respiratory Outcomes in a Single-Center, Retrospective Cohort, 2016-2018.

To describe our experience of using noninvasive neurally adjusted ventilatory assist (NIV-NAVA) in infants with bronchiolitis, its association with the evolution of respiratory effort, and PICU outcomes. Retrospective analysis of a prospectively curated, high-frequency electronic database. A PICU in a university-affiliated maternal-child health center in Canada. Patients younger than 2 years old who were admitted with a diagnosis of acute bronchiolitis and treated with NIV-NAVA from October 2016 to June 2018. None. Patient characteristics, as well as respiratory and physiologic parameters, including electrical diaphragmatic activity (Edi), were extracted from the electronic database. Respiratory effort was estimated using the modified Wood Clinical Asthma Score (mWCAS) and the inspiratory Edi. A comparison in the respiratory effort data was made between the 2 hours before and 2 hours after starting NIV-NAVA. In the two seasons, 64 of 205 bronchiolitis patients were supported with NIV-NAVA. These 64 patients had a median (interquartile range [IQR]) age of 52 days (32-92 d), and there were 36 of 64 males. Treatment with NIV-NAVA was used after failure of first-tier noninvasive respiratory support; 25 of 64 patients (39%) had at least one medical comorbidity. NIV-NAVA initiation was associated with a moderate decrease in mWCAS from 3.0 (IQR, 2.5-3.5) to 2.5 (IQR, 2.0-3.0; p < 0.001). NIV-NAVA initiation was also associated with a statistically significant decrease in Edi ( p < 0.01). However, this decrease was only clinically relevant in infants with a 2-hour baseline Edi greater than 20 μV; here, the before and after Edi was 44 μV (IQR, 33-54 μV) compared with 27 μV (IQR, 21-36 μV), respectively ( p < 0.001). Overall, six of 64 patients (9%) required endotracheal intubation. In this single-center retrospective cohort, in infants with bronchiolitis who were considered to have failed first-tier noninvasive respiratory support, the use of NIV-NAVA was associated with a rapid decrease in respiratory effort and a 9% intubation rate.

Attributes That Increase Vulnerabilities to Reduced Human Milk Feeding Outcomes Among Babies With Cleft Lip and Palate in the Neonatal Intensive Care Unit.

The purpose of this study was to identify infant and maternal factors associated with reduced human milk feeding among infants in a neonatal intensive care unit (NICU) with cleft lip with or without cleft palate (CL ± P). Data collected on mothers and infants admitted to the NICU with CL ± P from the 2018 National Vital Statistics System were used for this study. Chi-square tests of independence and independent-samples t tests were used to compare categorical variables and continuous variables, respectively, among two groups of infants admitted to the NICU with CL ± P-those who did and did not receive human milk feeding at discharge. The sample included 660 infants admitted to the NICU with CL ± P, of which 353 received human milk at discharge. Significant differences were found between the two groups for marital status, mother's education, maternal smoking record, total number of prenatal visits, multiparity record, gestational age, birth weight, and use of assisted ventilation. Results indicated that, as a function of human milk feeding at discharge, mothers and their infants admitted to the NICU with CL ± P exhibited differences across infant and maternal factors. These findings further our understanding of this sample of mothers and infants with CL ± P while potentially identifying determinants to human milk feeding. This study provides insight into infant and maternal characteristics that may be associated with barriers to human milk feeding.

Neurally Adjusted Ventilatory Assist Versus Pressure Support Ventilation: A Comprehensive Review.

Mechanical ventilation serves as crucial life support for critically ill patients. Although it is life-saving prolonged ventilation carries risks and complications like barotrauma, Ventilator-associated pneumonia, sepsis, and many others. Optimizing patient-ventilator interactions and facilitating early weaning is necessary for improved intensive care unit (ICU) outcomes. Traditionally Pressure support ventilation (PSV) mode is widely used for weaning patients who are intubated and mechanically ventilated. Neurally adjusted ventilatory assist (NAVA) mode of the ventilator is an emerging ventilator mode that delivers pressure depending on the patient's respiratory drive, which in turn prevents over-inflation and improves the patient's ventilator interactions. Our article revises and compares the effectiveness of NAVA compared to PSV ventilation under different contexts. Overall we conclude that NAVA level of ventilation can be safely administered in a patient with acute respiratory failure, provided diaphragmatic paralysis is not considered. NAVA improves asynchrony index, wean-off time, and sleep quality and is associated with increased ventilator-free days. These results are based on small-scale studies with low power, and further studies are warranted in large-scale cohorts with more diverse populations to confirm these results.

Use of airway pressure-based indices to detect high and low inspiratory effort during pressure support ventilation: a diagnostic accuracy study

BackgroundAssessment of the patient’s respiratory effort is essential during assisted ventilation. We aimed to evaluate the accuracy of airway pressure (Paw)-based indices to detect potential injurious inspiratory effort during pressure support (PS) ventilation.MethodsIn this prospective diagnostic accuracy study conducted in four ICUs in two academic hospitals, 28 adult acute respiratory failure patients undergoing PS ventilation were enrolled. A downward PS titration was conducted from 20 cmH2O to 2 cmH2O at a 2 cmH2O interval. By performing an end-expiratory airway occlusion maneuver, the negative Paw generated during the first 100 ms (P0.1) and the maximal negative swing of Paw (∆Pocc) were measured. After an end-inspiratory airway occlusion, Paw reached a plateau, and the magnitude of change in plateau from peak Paw was measured as pressure muscle index (PMI). Esophageal pressure was monitored and inspiratory muscle pressure (Pmus) and Pmus–time product per minute (PTPmus/min) were used as the reference standard for the patient’s effort. High and low effort was defined as Pmus > 10 and < 5 cmH2O, or PTPmus/min > 200 and < 50 cmH2O s min−1, respectively.ResultsA total of 246 levels of PS were tested. The low inspiratory effort was diagnosed in 145 (59.0%) and 136 (55.3%) PS levels using respective Pmus and PTPmus/min criterion. The receiver operating characteristic area of the three Paw-based indices by the respective two criteria ranged from 0.87 to 0.95, and balanced sensitivity (0.83–0.96), specificity (0.74–0.88), and positive (0.80–0.91) and negative predictive values (0.78–0.94) were obtained. The high effort was diagnosed in 34 (13.8%) and 17 (6.9%) support levels using Pmus and PTPmus/min criterion, respectively. High receiver operating characteristic areas of the three Paw-based indices by the two criteria were found (0.93–0.95). A high sensitivity (0.80–1.00) and negative predictive value (0.97–1.00) were found with a low positive predictive value (0.23–0.64).ConclusionsBy performing simple airway occlusion maneuvers, the Paw-based indices could be reliably used to detect low inspiratory efforts. Non-invasive and easily accessible characteristics support their potential bedside use for avoiding over-assistance. More evaluation of their performance is required in cohorts with high effort.

Application of Cut-and-Sew Technique in Thoracoscopic Minimally Invasive Mitral Valve Surgery and Concomitant Maze Procedure.

Atrial fibrillation is one of the common complications of mitral valve disease. Currently, in the absence of freezing equipment, it's still impossible to fully conduct a minimally invasive Cox-maze IV procedure to treat atrial fibrillation. We analyzed the clinical data of 28 patients who underwent thoracoscopic minimally invasive mitral valve full maze surgery in our hospital from October 2021 to September 2022; 13 patients were male and 15 were female, three suffered from paroxysmal atrial fibrillation, and 25 suffered from permanent atrial fibrillation; average age was 61.88±8.30 years, and mean preoperative left atrial diameter was 47.12±8.34 mm. Isolation of left atrial posterior wall (box lesion) was completed in all patients by cut-and-sew technique and bipolar clamp ablation. For these subjects, the median cardiopulmonary bypass time was 169 (109.75-202.75) minutes, aortic cross-clamping time was 106 (77.75-125.50) minutes, and ventilator assistance time was 6.5 (0-10) hours. Among them, eight subjects had the endotracheal tubes removed immediately after surgical operation. Three subjects were in the blanking period; two subjects still had atrial fibrillation at three months after operation, one of whom resumed sinus rhythm after electrical cardioversion therapy; and all the remaining 23 subjects had sinus rhythm. The minimally invasive cut-and-sew technique for electrical isolation of left pulmonary veins can improve sinus conversion rate of patients suffering from both mitral valve disease and atrial fibrillation. In selected subjects, it is safe and has good results in the short-term postoperative period.

Interpretable machine learning models for early prediction of acute kidney injury after cardiac surgery

ObjectivePostoperative acute kidney injury (PO-AKI) is a common complication after cardiac surgery. We aimed to evaluate whether machine learning algorithms could significantly improve the risk prediction of PO-AKI.MethodsThe retrospective cohort study included 2310 adult patients undergoing cardiac surgery in a tertiary teaching hospital, China. Postoperative AKI and severe AKI were identified by the modified KDIGO definition. The sample was randomly divided into a derivation set and a validation set based on a ratio of 4:1. Exploiting conventional logistic regression (LR) and five ML algorithms including decision tree, random forest, gradient boosting classifier (GBC), Gaussian Naive Bayes and multilayer perceptron, we developed and validated the prediction models of PO-AKI. We implemented the interpretation of models using SHapley Additive exPlanation (SHAP) analysis.ResultsPostoperative AKI and severe AKI occurred in 1020 (44.2%) and 286 (12.4%) patients, respectively. Compared with the five ML models, LR model for PO-AKI exhibited the largest AUC (0.812, 95%CI: 0.756, 0.860, all P < 0.05), sensitivity (0.774, 95%CI: 0.719, 0.813), accuracy (0.753, 95%CI: 0.719, 0.781) and Youden index (0.513, 95%CI: 0.451, 0.573). Regarding severe AKI, GBC algorithm showed a significantly higher AUC than the other four ML models (all P < 0.05). Although no significant difference (P = 0.173) was observed in AUCs between GBC (0.86, 95%CI: 0.808, 0.902) and conventional logistic regression (0.803, 95%CI: 0.746, 0.852), GBC achieved greater sensitivity, accuracy and Youden index than conventional LR. Notably, SHAP analyses showed that preoperative serum creatinine, hyperlipidemia, lipid-lowering agents and assisted ventilation time were consistently among the top five important predictors for both postoperative AKI and severe AKI.ConclusionLogistic regression and GBC algorithm demonstrated moderate to good discrimination and superior performance in predicting PO-AKI and severe AKI, respectively. Interpretation of the models identified the key contributors to the predictions, which could potentially inform clinical interventions.

A Case of Pulmonary Interstitial Emphysema and Systematic Review of Literature in Management Approach

Background: Pulmonary interstitial emphysema (PIE) is a rare pathology characterized by the abnormal and harmful presence of air in the interstitial tissues of the lung. This condition is often related to barotrauma caused by mechanical ventilation, but it can be exceptionally seen in healthy infants. The main causes of PIE are respiratory distress syndrome (RDS), mechanical ventilation or positive pressure ventilation, prematurity, meconium aspiration syndrome, pulmonary infection, amniotic fluid aspiration, and incorrect endotracheal tube placement. To date, there is no standard treatment for PIE, based on the clinical and localization of PIE conservative and non-- conservative therapies are described. Methods: We describe a case of a very premature infant with severe respiratory failure secondary to RDS and unilateral left sided PIE with lung herniation treated with conservative therapy like selective intubation, steroid therapy, lateral position, and lastly, oxygen supplementation without ventilatory assistance. Furthermore, we have carried out a systematic literature review for the past 15 years (2007-2022). A systematic review, using an evidence-based algorithmic approach, was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Results: Our search, after the selection, produced a total of 24 articles, which were revised. Conclusion: In our case oxygen supplementation without ventilatory assistance resulted in successful resolution of the left PIE. Discontinuation of ventilatory care played a crucial role. Considering the management reported in literature, our aim is to perform a systematic literature review by adding our experience to the available knowledge on therapy for unilateral PIE.

Research advances on neurally adjusted ventilatory assist

Mechanical ventilation has, since its introduction into clinical practice, undergone a major evolution from controlled ventilation to diverse modes of assisted ventilation. Conventional mechanical ventilators depend on flow sensors and pneumatic pressure and controllers to complete the respiratory cycle. Neurally adjusted ventilatory assist (NAVA) is a new form of assisted ventilation in recent years, which monitors the electrical activity of the diaphragm (EAdi) to provide an appropriately level of pressure support. And EAdi is the best available signal to sense central respiratory drive and trigger ventilatory assist. Unlike other ventilation modes, NAVA breathing instructions come from the center. Therefore, NAVA have the synchronous nature of the breaths and the patient-adjusted nature of the support. Compared with traditional ventilation mode, NAVA can efficiently unload respiratory muscles, relieve the risk of ventilator-induced lung injury (VILI), improve patient-ventilator coordination, enhance gas exchange, increase the success rate of weaning, etc. This article reviews the research progress of NAVA in order to provide theoretical guidance for clinical applications.

The use of neonatal bubble Continuous Positive Airway Pressure in a rural hospital setting.

This retrospective review examined the introduction of bubble Continuous Positive Airway Pressure (bCPAP) in resuscitating neonates in a rural hospital environment. A retrospective audit of all emergent neonatal presentations to a rural emergency department (ED) over a 5-year period prior to (pre) and a 3.5-year period following the introduction of bCPAP (post). Sixty-seven neonatal resuscitations (31 pre- and 36 post-introduction of bCPAP) were reviewed, having an average gestation of 37.4 weeks and birth weight of 3,110g, with no significant difference in characteristics between groups. Time in the ED was significantly longer post-bCPAP (202±93 vs 156±70 mins), but time applying T-piece assisted ventilation was significantly reduced (55±40 vs 94 ± 84 mins). There was an 11% reduction in the use of aeromedical retrieval and an 18% reduction in admissions to the regional level III neonatal intensive care unit (NICU) with a corresponding increase in admissions to local level II NICU. The introduction of bCPAP into a rural hospital setting is technically feasible and results in less time spent on technically demanding hand ventilation, fewer admissions to level III neonatal intensive care units and a reduction in the use of aeromedical retrieval assets.

Efficient Algorithm for Pulmonary Nonlinear Model Online Estimation of Patients Under Assisted Ventilation

An efficient algorithm to estimate a respiratory system nonlinear model of sedated patients under assisted ventilation is presented. The considered model comprises an airways resistance and a volume-dependant compliance and, for each respiratory cycle, the proposed algorithm provides online the model parameters guaranteeing a minimum accuracy, above a user-defined threshold. Relying on standard nonlinear identification techniques, it exhibits computational burden reduction features, which contribute to its suitability for its online application.

Prediction of mechanical ventilation outcome by early abdominal-visceral-blood-flow-and-function score in critically ill patients after cardiopulmonary bypass in the ICU: A prospective observational study

BackgroundAbdominal organs are important organs that sense and respond to ischemia and hypoxia, but there are few evaluation methods.We use ultrasonography to evaluate abdominal organ function and blood flow in patients with mechanical ventilation (MV) after cardiopulmonary bypass and to obtain a semiquantitative score for abdominal organ function and blood flow. MethodsPatients with cardiopulmonary bypass in the Critical Care Department of Peking Union Medical College Hospital in China from March to July 2021 were enrolled in this prospective observational study. The correlation of the abdominal-visceral-blood-flow-and-function score (AVBFS) with the duration of MV, number of days spent in the intensive care unit (ICU), acute physiology and chronic health evaluation II (APACHE-II), sequential organ failure assessment (SOFA), lactate, epinephrine, and norepinephrine use was analyzed, and the results were used to assess the predictive value of the receiver operating characteristic curve (ROC) regression analysis score for the duration of MV. ResultsOf the 92 patients who underwent cardiopulmonary bypass, 41 were finally included. The AVBFS were significantly correlated with the duration of MV, number of days spent in the ICU, APACHE-II score, SOFA score, and norepinephrine use time. The AVBFS in a group of patients using ventilators ≥36 h were significantly higher than those obtained for a group of patients using ventilators <36 h (P <0.05). The evaluation results for the AVBFS at 0-12 h after ICU admission were as follows: area under the ROC curve (AUC)=0.876 (95% confidence interval [CI]: 0.767 to 0.984), cut-off value=2.5, specificity=0.842, and sensitivity=0.773. ConclusionsAbdominal visceral organ function and blood perfusion can be used to evaluate gastrointestinal function. It is related to early and late extubation after cardiac surgery.