ABSTRACT
Carbapenem-resistant Acinetobacter baumannii (CRAB) pneumonia has been a serious problem in the intensive care unit (ICU). However, defined characteristics of respiratory microbiome in CRAB pneumonia are lacking nowadays. This study aimed to analyze respiratory microbiome of CRAB pneumonia compared to non-CRAB pneumonia and reveal the clinical significance of respiratory microbiome data in these patients. Patients diagnosed with severe pneumonia with mechanical ventilation were enrolled in the ICU of a tertiary care hospital. Respiratory specimens were collected on days 1, 4, 7, and 14 in each participant via tracheal aspiration. Clinical data and outcomes of each enrolled patient were collected via electronic medical records. Microbiome analysis was conducted with collected respiratory specimens undergone by next-generation sequencing of microbial 16S ribosomal DNA. Six CRAB pneumonia, 4 non-CRAB pneumonia and 5 healthy controls were enrolled. In CRAB pneumonia, CRAB was detected in 3 patients by sputum culture at day 1, while it was negative at day 1 and detected later in the others by follow-up sputum culture. Beta diversity plot analysis showed differences between each group. Shannon index was decreased markedly at day 4 in CRAB pneumonia compared to the others. Among CRAB pneumonia cases, 3 respiratory specimens were culture-negative, but positive by microbiome analysis. Lower respiratory microbiome in CRAB pneumonia had distinct characteristics and early loss of diversity compared to non-CRAB pneumonia, which might be related to poor clinical course. Moreover, CRAB acquisition and colonization would be predicted by preemptive microbiome analysis, which will contribute to effective infection control in the ICU.
Subject(s)
Acinetobacter Infections , Acinetobacter baumannii , Carbapenems , Critical Illness , Microbiota , Humans , Acinetobacter baumannii/isolation & purification , Acinetobacter baumannii/drug effects , Male , Carbapenems/pharmacology , Carbapenems/therapeutic use , Female , Middle Aged , Acinetobacter Infections/microbiology , Acinetobacter Infections/drug therapy , Microbiota/drug effects , Aged , Intensive Care Units/statistics & numerical data , Pneumonia, Bacterial/microbiology , Pneumonia, Bacterial/drug therapy , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/pharmacology , Sputum/microbiology , Respiration, Artificial/adverse effectsABSTRACT
BACKGROUND: In the United States in 2017, there were an estimated 903,745 hospitalizations involving mechanical ventilation (MV). Complications from ventilation can result in longer hospital stays, increased risk of disability, and increased healthcare costs. It has been hypothesized that electrically pacing the diaphragm by phrenic nerve stimulation during mechanical ventilation may minimize or reverse diaphragm dysfunction, resulting in faster weaning. METHODS: The ReInvigorate Trial is a prospective, multicenter, randomized, controlled clinical trial evaluating the safety and efficacy of Stimdia's pdSTIM System for facilitating weaning from MV. The pdSTIM system employs percutaneously placed multipolar electrodes to stimulate the cervical phrenic nerves and activate contraction of the diaphragm bilaterally. Patients who were on mechanical ventilation for at least 96 h and who failed at least one weaning attempt were considered for enrollment in the study. The primary efficacy endpoint was the time to successful liberation from mechanical ventilation (treatment vs. control). Secondary endpoints will include the rapid shallow breathing index and other physiological and system characteristics. Safety will be summarized for both primary and additional analyses. All endpoints will be evaluated at 30 days or at the time of removal of mechanical ventilation, whichever is first. DISCUSSION: This pivotal study is being conducted under an investigational device exception with the U.S. Food and Drug Administration. The technology being studied could provide a first-of-kind therapy for difficult-to-wean patients on mechanical ventilation in an intensive care unit setting. TRIAL REGISTRATION: Clinicaltrials.gov, NCT05998018 , registered August 2023.
Subject(s)
Diaphragm , Multicenter Studies as Topic , Phrenic Nerve , Randomized Controlled Trials as Topic , Ventilator Weaning , Humans , Ventilator Weaning/methods , Diaphragm/innervation , Phrenic Nerve/physiology , Prospective Studies , Time Factors , Treatment Outcome , Respiration, Artificial/adverse effects , Respiration, Artificial/methods , Electric Stimulation Therapy/methods , Electric Stimulation Therapy/adverse effects , Electric Stimulation Therapy/instrumentationABSTRACT
Invasive devices are routinely used in the care of critically ill patients. Although they are often essential components of patient care, devices such as intravascular catheters, endotracheal tubes, and ventilators are a common source of complications in the intensive care unit. Critical care practitioners who use these devices need to use strategies for risk reduction and understand approaches to management when adverse events occur. This review discusses the identification, prevention, and management of complications of vascular, airway, and mechanical support devices commonly used in the intensive care unit.
Subject(s)
Intensive Care Units , Intubation, Intratracheal , Humans , Intubation, Intratracheal/adverse effects , Intubation, Intratracheal/instrumentation , Critical Care , Ventilators, Mechanical/adverse effects , Respiration, Artificial/instrumentation , Respiration, Artificial/adverse effects , Critical Illness/therapyABSTRACT
Mechanical ventilation exposes the lung to injurious stresses and strains that can negatively affect clinical outcomes in acute respiratory distress syndrome or cause pulmonary complications after general anesthesia. Excess global lung strain, estimated as increased respiratory system driving pressure, is associated with mortality related to mechanical ventilation. The role of small-dimension biomechanical factors underlying this association and their spatial heterogeneity within the lung are currently unknown. Using four-dimensional computed tomography with a voxel resolution of 2.4 cubic millimeters and a multiresolution convolutional neural network for whole-lung image segmentation, we dynamically measured voxel-wise lung inflation and tidal parenchymal strains. Healthy or injured ovine lungs were evaluated as the mechanical ventilation positive end-expiratory pressure (PEEP) was titrated from 20 to 2 centimeters of water. The PEEP of minimal driving pressure (PEEPDP) optimized local lung biomechanics. We observed a greater rate of change in nonaerated lung mass with respect to PEEP below PEEPDP compared with PEEP values above this threshold. PEEPDP similarly characterized a breaking point in the relationships between PEEP and SD of local tidal parenchymal strain, the 95th percentile of local strains, and the magnitude of tidal overdistension. These findings advance the understanding of lung collapse, tidal overdistension, and strain heterogeneity as local triggers of ventilator-induced lung injury in large-animal lungs similar to those of humans and could inform the clinical management of mechanical ventilation to improve local lung biomechanics.
Subject(s)
Lung , Positive-Pressure Respiration , Respiration, Artificial , Animals , Lung/physiopathology , Sheep , Biomechanical Phenomena , Respiration, Artificial/adverse effects , Pressure , Tomography, X-Ray Computed , Tidal VolumeABSTRACT
This case report describes laryngeal oedema occurring in a 35-year-old woman with chronic bowel-associated dermatosis-arthritis syndrome, and stenosis of the left main bronchus. The oedema was attributed to persistent cough exacerbated by delayed treatment and intubation-related irritation. Evaluations ruled out inflammatory, autoimmune, and malignant causes. Literature lacks on specific descriptions of cough-induced laryngeal oedema, emphasizing the need for a multidisciplinary approach and early intervention in complex cases to prevent severe hospitalizations in patients with known serious conditions and symptom exacerbation.
Subject(s)
Cough , Laryngeal Edema , Humans , Adult , Female , Cough/etiology , Laryngeal Edema/etiology , Respiration, Artificial/adverse effects , Intubation, Intratracheal/adverse effectsABSTRACT
BACKGROUND: Ventilator-associated pneumonia (VAP) is a prevalent and grave hospital-acquired infection that affects mechanically ventilated patients. Diverse diagnostic criteria can significantly affect VAP research by complicating the identification and management of the condition, which may also impact clinical management. OBJECTIVES: We conducted this review to assess the diagnostic criteria and the definitions of the term "ventilator-associated" used in randomised controlled trials (RCTs) of VAP management. SEARCH METHODS: Based on the protocol (PROSPERO 2019 CRD42019147411), we conducted a systematic search on MEDLINE/PubMed and Cochrane CENTRAL for RCTs, published or registered between 2010 and 2024. SELECTION CRITERIA: We included completed and ongoing RCTs that assessed pharmacological or non-pharmacological interventions in adults with VAP. DATA COLLECTION AND SYNTHESIS: Data were collected using a tested extraction sheet, as endorsed by the Cochrane Collaboration. After cross-checking, data were summarised in a narrative and tabular form. RESULTS: In total, 7,173 records were identified through the literature search. Following the exclusion of records that did not meet the eligibility criteria, 119 studies were included. Diagnostic criteria were provided in 51.2% of studies, and the term "ventilator-associated" was defined in 52.1% of studies. The most frequently included diagnostic criteria were pulmonary infiltrates (96.7%), fever (86.9%), hypothermia (49.1%), sputum (70.5%), and hypoxia (32.8%). The different criteria were used in 38 combinations across studies. The term "ventilator-associated" was defined in nine different ways. CONCLUSIONS: When provided, diagnostic criteria and definitions of VAP in RCTs display notable variability. Continuous efforts to harmonise VAP diagnostic criteria in future clinical trials are crucial to improve quality of care, enable accurate epidemiological assessments, and guide effective antimicrobial stewardship.
Subject(s)
Pneumonia, Ventilator-Associated , Humans , Pneumonia, Ventilator-Associated/diagnosis , Randomized Controlled Trials as Topic , Respiration, Artificial/adverse effects , Respiration, Artificial/methodsABSTRACT
OBJECTIVE: This study aims to evaluate the performance of the fabian-Predictive-Intelligent-Control-of-Oxygenation (PRICO) system for automated control of the fraction of inspired oxygen (FiO2). DESIGN: Multicentre randomised cross-over study. SETTING: Five neonatal intensive care units experienced with automated control of FiO2 and the fabian ventilator. PATIENTS: 39 infants: median gestational age of 27 weeks (IQR: 26-30), postnatal age 7 days (IQR: 2-17), weight 1120 g (IQR: 915-1588), FiO2 0.32 (IQR: 0.22-0.43) receiving both non-invasive (27) and invasive (12) respiratory support. INTERVENTION: Randomised sequential 24-hour periods of automated and manual FiO2 control. MAIN OUTCOME MEASURES: Proportion (%) of time in normoxaemia (90%-95% with FiO2>0.21 and 90%-100% when FiO2=0.21) was the primary endpoint. Secondary endpoints were severe hypoxaemia (<80%) and severe hyperoxaemia (>98% with FiO2>0.21) and prevalence of episodes ≥60 s at these two SpO2 extremes. RESULTS: During automated control, subjects spent more time in normoxaemia (74%±22% vs 51%±22%, p<0.001) with less time above and below (<90% (9%±8% vs 12%±11%, p<0.001) and >95% with FiO2>0.21 (16%±19% vs 35%±24%) p<0.001). They spent less time in severe hyperoxaemia (1% (0%-3.5%) vs 5% (1%-10%), p<0.001) but exposure to severe hypoxaemia was low in both arms and not different. The differences in prolonged episodes of SpO2 were consistent with the times at extremes. CONCLUSIONS: This study demonstrates the ability of the PRICO automated oxygen control algorithm to improve the maintenance of SpO2 in normoxaemia and to avoid hyperoxaemia without increasing hypoxaemia.
Subject(s)
Cross-Over Studies , Intensive Care Units, Neonatal , Oxygen Saturation , Humans , Infant, Newborn , Female , Male , Hypoxia , Hyperoxia/prevention & control , Oxygen/blood , Oxygen/administration & dosage , Oximetry/methods , Oxygen Inhalation Therapy/methods , Oxygen Inhalation Therapy/adverse effects , Oxygen Inhalation Therapy/instrumentation , Respiration, Artificial/adverse effects , Infant, PrematureABSTRACT
OBJECTIVES: to analyze the profile and clinical outcomes of patients who developed Ventilator-Associated Pneumonia (VAP) in private home care and to compare the incidence with national data. METHODS: this was a retrospective study with data collected from July 2021 to June 2022 from patient records at a private clinic. Patients using intermittent ventilation or without ventilatory support were excluded. RESULTS: the utilization rate of mechanical ventilation was 15.9%. The incidence density of pneumonia in pediatrics was 2.2 cases per 1000 ventilation-days and in adults was 1.7 cases per 1000 ventilation-days, figures lower than those reported by the National Health Surveillance Agency. There were 101 episodes of pneumonia in 73 patients, predominantly male (65.8%), adults (53.4%), and those with neurological diseases (57.5%). The treatment regimen predominantly took place at home (80.2%), and there was one death. CONCLUSIONS: patients in home care showed a low incidence and mortality rate from ventilator-associated pneumonia.
Subject(s)
Home Care Services , Pneumonia, Ventilator-Associated , Humans , Male , Female , Pneumonia, Ventilator-Associated/epidemiology , Pneumonia, Ventilator-Associated/etiology , Retrospective Studies , Home Care Services/statistics & numerical data , Home Care Services/standards , Home Care Services/trends , Adult , Middle Aged , Incidence , Adolescent , Child , Aged , Brazil/epidemiology , Child, Preschool , Respiration, Artificial/adverse effects , Respiration, Artificial/statistics & numerical data , InfantABSTRACT
This study evaluates the non-invasive diagnosis of Invasive Aspergillosis Pneumonia (IPA) in mechanically ventilated patients by measuring galactomannan (GM) in exhaled breath condensate (EBC). Utilizing a rat model and a novel EBC collection device, we compared GM levels in bronchoalveolar lavage fluid (BALF) and EBC, supplemented by cytokine profiling. Analysis of 75 patients confirmed the device's efficacy, with EBC-GM and BALF-GM showing high diagnostic accuracy (AUC = 0.88). The threshold of 0.235 ng/ml for EBC-GM achieved 92.8 % sensitivity and 66.7 % specificity, with a strong correlation (r = 0.707, P < 0.001) with BALF-GM. This approach offers a safe, effective alternative to invasive diagnostics, enhancing precision with IL-6 and TNF-α measurements. The number registered on clinicaltrails.gov is NCT06333379.
Subject(s)
Breath Tests , Bronchoalveolar Lavage Fluid , Galactose , Mannans , Sensitivity and Specificity , Mannans/analysis , Galactose/analogs & derivatives , Humans , Breath Tests/methods , Male , Animals , Bronchoalveolar Lavage Fluid/chemistry , Bronchoalveolar Lavage Fluid/microbiology , Female , Middle Aged , Rats , Aged , Respiration, Artificial/adverse effects , Invasive Pulmonary Aspergillosis/diagnosis , Cytokines/analysis , Cytokines/metabolism , ExhalationABSTRACT
OBJECTIVE: ICU delirium commonly complicates critical illness associated with factors such as cardiopulmonary bypass (CPB) time and the requirement of mechanical ventilation (MV). Recent reports associate hyperoxia with poorer outcomes in critically ill children. This study sought to determine whether hyperoxia on CPB in pediatric patients was associated with a higher prevalence of postoperative delirium. DESIGN: Secondary analysis of data obtained from a prospective cohort study. SETTING: Twenty-two-bed pediatric cardiac ICU in a tertiary children's hospital. PATIENTS: All patients (18 yr old or older) admitted post-CPB, with documented delirium assessment scores using the Preschool/Pediatric Confusion Assessment Method for the ICU and who were enrolled in the Precision Medicine in Pediatric Cardiology Cohort from February 2021 to November 2021. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 148 patients, who underwent cardiac surgery, 35 had delirium within the first 72 hours (24%). There was no association between hyperoxia on CPB and postoperative delirium for all definitions of hyperoxia, including hyperoxic area under the curve above 5 predetermined Pao2 levels: 150 mm Hg (odds ratio [95% CI]: 1.176 [0.605-2.286], p = 0.633); 175 mm Hg (OR 1.177 [95% CI, 0.668-2.075], p = 0.572); 200 mm Hg (OR 1.235 [95% CI, 0.752-2.026], p = 0.405); 250 mm Hg (OR 1.204 [95% CI, 0.859-1.688], p = 0.281), 300 mm Hg (OR 1.178 [95% CI, 0.918-1.511], p = 0.199). In an additional exploratory analysis, comparing patients with delirium within 72 hours versus those without, only the z score for weight differed (mean [sd]: 0.09 [1.41] vs. -0.48 [1.82], p < 0.05). When comparing patients who developed delirium at any point during their ICU stay (n = 45, 30%), MV days, severity of illness (Pediatric Index of Mortality 3 Score) score, CPB time, and z score for weight were associated with delirium (p < 0.05). CONCLUSIONS: Postoperative delirium (72 hr from CPB) occurred in 24% of pediatric patients. Hyperoxia, defined in multiple ways, was not associated with delirium. On exploratory analysis, nutritional status (z score for weight) may be a significant factor in delirium risk. Further delineation of risk factors for postoperative delirium versus ICU delirium warrants additional study.
Subject(s)
Cardiopulmonary Bypass , Delirium , Hyperoxia , Intensive Care Units, Pediatric , Postoperative Complications , Humans , Hyperoxia/complications , Male , Female , Cardiopulmonary Bypass/adverse effects , Prospective Studies , Child , Postoperative Complications/etiology , Postoperative Complications/epidemiology , Delirium/etiology , Delirium/epidemiology , Child, Preschool , Adolescent , Infant , Cohort Studies , Risk Factors , Respiration, Artificial/adverse effectsABSTRACT
BACKGROUND: Airway injuries are reported among preterm infants with bronchopulmonary dysplasia. We hypothesized that prolonged ventilation in preterm infants is associated with subglottic dilatation that can be reliably evaluated by point of care ultrasonography (POCUS). METHODS: All preterm infants (<29-weeks) admitted to the neonatal ICU at the Advent-Health from January-2020 to June-2022 were eligible if they required invasive ventilation for ≤7 days in the first 28 days of life (control) or remained intubated for ≥28 days (prolonged ventilation). Sonography was performed by one technician and all images were reviewed by the pediatric radiologist. The trachea size was measured 3 times by randomly selecting three images. The first 20 scans were also independently reported by a different pediatric radiologist. Intra and inter-observer variability was estimated. Mean trachea size and weight at the time of imaging were compared. RESULTS: Out of 417 eligible infants; 11 died before 28 days and 163 required ventilation for 8-27 days. Consent missed for 80 infants during COVID-19 pandemic. We enrolled 23 and 28 infants in the control & prolonged ventilation groups, respectively. Inter and intra-observer correlations were 0.83 and 0.97 respectively. Infants in the control group had higher gestation and birth weight. Infants on prolonged ventilation were at higher risk for infections, BPD, longer hospital stay and significant subglottic dilation (4.51 ± 0.04 vs 4.17 ± 0.02 mm, p < 0.01) despite smaller body weight at the time of imaging (884 ± 102 vs 1059 ± 123g, p < 0.01). CONCLUSION: Extremely preterm infants on prolonged ventilation are at risk for sub-glottic dilatation that can be reliably measured by POCUS.
Subject(s)
Bronchopulmonary Dysplasia , Infant, Extremely Premature , Respiration, Artificial , Trachea , Ultrasonography , Humans , Infant, Newborn , Respiration, Artificial/adverse effects , Respiration, Artificial/methods , Male , Female , Trachea/diagnostic imaging , Bronchopulmonary Dysplasia/diagnostic imaging , Bronchopulmonary Dysplasia/etiology , Ultrasonography/methods , Dilatation, Pathologic/diagnostic imaging , Glottis/diagnostic imaging , COVID-19/complications , Time FactorsABSTRACT
BACKGROUND: An air embolism is a rare complication that occurs after air enters blood vessels, causing almost no to mild symptoms in patients. Although uncommon, air embolism can be deadly. Critical care professionals should know the warning signs of air embolism and be prepared to carry out the necessary therapeutic interventions. To reduce morbidity and death, this clinical condition must be identified early. Here we are presenting a case of pulmonary artery air embolism as a consequence of contrast agent injection in a chest computed tomography study. CASE PRESENTATION: A 70-year-old male patient were presented with pulmonary artery air embolism as a consequence of contrast agent injection in a chest computed tomography study. The patient experienced worsening respiratory symptoms that necessitated oxygen therapy, which resulted in respiratory alkalosis with secondary metabolic alkalosis. Following removal of the BiLevel positive airway pressure, the patient was switched to a 2-L nasal cannula, and his breathing rate increased to 34 breaths/min. After 8.5 hours of monitoring the patient's vital signs, the nasal cannula was removed, and the patient began breathing room air on his own. His vital signs then stabilized and arterial blood gas parameters returned to normal. The patient's condition improved, and he was discharged from the hospital after 9 days. Due to a high level of cytomegalovirus, the discharge prescriptions included valganciclovir film-coated tablets (900 mg, oral BID every 12 hours for 30 days) and apixaban (5 mg BID). The patient was then monitored at the outpatient clinic. CONCLUSION: Although rare, an air embolism can cause minor symptoms if it is small in volume or can be fatal if large. After contrast-enhanced radiological studies, physicians should be aware of any signs of respiratory distress or worsening of symptoms in their patients. Additionally, patients should be mindful of the potential complications associated with ventilation therapy.
Subject(s)
Embolism, Air , Humans , Male , Aged , Embolism, Air/etiology , Embolism, Air/therapy , Alkalosis, Respiratory/etiology , Pulmonary Embolism/etiology , Alkalosis/etiology , Tomography, X-Ray Computed , Contrast Media/adverse effects , Pulmonary Artery , Respiration, Artificial/adverse effects , Respiration, Artificial/methodsABSTRACT
PURPOSE: To investigate esketamine's impact on inflammation and oxidative stress in ventilated chronic obstructive pulmonary disease (COPD) rats, examining its regulatory mechanisms. METHODS: Rats were divided into four groups: control group (Con), COPD model group (M), COPD model with saline treatment group (M+S), and COPD model with esketamine treatment group (M+K), with 12 rats in each group. After two months, all rats underwent anesthesia and mechanical ventilation. Group M+K received 5 mg/kg esketamine intravenously, while Group M+S received the same volume of saline. Lung tissues were collected for analysis two hours later, including airway peak pressure, wet-to-dry(W/D) ratio, lung permeability index(LPI), hematoxylin and eosin(H&E) staining, and transmission electron microscopy(TEM). Tumor necrosis factor-alpha(TNF-α), interleukin-6(IL-6), interleukin-8(IL-8), and interleukin-10(IL-10) levels were determined by enzyme-linked immunosorbent assay(ELISA); phosphorylated Nuclear Factor Kappa B(p-NF-κB), mitogen-activated protein kinase 14(p38), phosphorylated p38 (p-p38), c-Jun N-terminal kinase(JNK), and phosphorylated JNK (p-JNK) expressions by Western blotting and immunohistochemistry; and malondialdehyde(MDA), myeloperoxidase(MPO), and superoxide dismutase(SOD) levels were also measured by corresponding biochemical assays. RESULTS: Lung specimens from groups M, M+S, and M+K manifested hallmark histopathological features of COPD. Compared with group Con, group M displayed increased peak airway pressure, W/D ratio, and LPI. In group M+K, compared with group M, esketamine significantly reduced the W/D ratio, LPI, and concentrations of pro-inflammatory cytokines TNF-α, IL-6, and IL-8 while concurrently elevating IL-10 levels. Furthermore, the treatment attenuated the activation of the NF-κB and MAPK pathways, indicated by decreased levels of p-NF-κB, p-p38, and p-JNK.Additionally, compared to group M, group M+K showed decreased MDA and MPO levels and increased SOD levels in lung tissue. CONCLUSION: Esketamine attenuates mechanical ventilation-induced lung injury in COPD rat models by inhibiting the MAPK/NF-κB signaling pathway and reducing oxidative stress.
Subject(s)
Cytokines , Ketamine , Lung , NF-kappa B , Oxidative Stress , Pulmonary Disease, Chronic Obstructive , Rats, Sprague-Dawley , Signal Transduction , Animals , Ketamine/therapeutic use , Ketamine/pharmacology , Oxidative Stress/drug effects , NF-kappa B/metabolism , Pulmonary Disease, Chronic Obstructive/drug therapy , Pulmonary Disease, Chronic Obstructive/metabolism , Male , Cytokines/metabolism , Rats , Lung/pathology , Lung/drug effects , Lung/metabolism , Lung/immunology , Signal Transduction/drug effects , Ventilator-Induced Lung Injury/drug therapy , Ventilator-Induced Lung Injury/metabolism , Ventilator-Induced Lung Injury/pathology , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Disease Models, Animal , Respiration, Artificial/adverse effects , Humans , MAP Kinase Signaling System/drug effects , Mitogen-Activated Protein Kinases/metabolismABSTRACT
Background and Objectives: Intra-abdominal hypertension (IAH) and acute respiratory distress syndrome (ARDS) are common concerns in intensive care unit patients with acute respiratory failure (ARF). Although both conditions lead to impairment of global respiratory parameters, their underlying mechanisms differ substantially. Therefore, a separate assessment of the different respiratory compartments should reveal differences in respiratory mechanics. Materials and Methods: We prospectively investigated alterations in lung and chest wall mechanics in 18 mechanically ventilated pigs exposed to varying levels of intra-abdominal pressures (IAP) and ARDS. The animals were divided into three groups: group A (IAP 10 mmHg, no ARDS), B (IAP 20 mmHg, no ARDS), and C (IAP 10 mmHg, with ARDS). Following induction of IAP (by inflating an intra-abdominal balloon) and ARDS (by saline lung lavage and injurious ventilation), respiratory mechanics were monitored for six hours. Statistical analysis was performed using one-way ANOVA to compare the alterations within each group. Results: After six hours of ventilation, end-expiratory lung volume (EELV) decreased across all groups, while airway and thoracic pressures increased. Significant differences were noted between group (B) and (C) regarding alterations in transpulmonary pressure (TPP) (2.7 ± 0.6 vs. 11.3 ± 2.1 cmH2O, p < 0.001), elastance of the lung (EL) (8.9 ± 1.9 vs. 29.9 ± 5.9 cmH2O/mL, p = 0.003), and elastance of the chest wall (ECW) (32.8 ± 3.2 vs. 4.4 ± 1.8 cmH2O/mL, p < 0.001). However, global respiratory parameters such as EELV/kg bodyweight (-6.1 ± 1.3 vs. -11.0 ± 2.5 mL/kg), driving pressure (12.5 ± 0.9 vs. 13.2 ± 2.3 cmH2O), and compliance of the respiratory system (-21.7 ± 2.8 vs. -19.5 ± 3.4 mL/cmH2O) did not show significant differences among the groups. Conclusions: Separate measurements of lung and chest wall mechanics in pigs with IAH or ARDS reveals significant differences in TPP, EL, and ECW, whereas global respiratory parameters do not differ significantly. Therefore, assessing the compartments of the respiratory system separately could aid in identifying the underlying cause of ARF.
Subject(s)
Disease Models, Animal , Intra-Abdominal Hypertension , Respiratory Distress Syndrome , Respiratory Mechanics , Animals , Respiratory Distress Syndrome/physiopathology , Intra-Abdominal Hypertension/physiopathology , Intra-Abdominal Hypertension/complications , Swine , Respiratory Mechanics/physiology , Respiration, Artificial/adverse effects , Respiration, Artificial/methods , Prospective StudiesABSTRACT
Patients with acute exacerbation of lung fibrosis with usual interstitial pneumonia (EUIP) pattern are at increased risk for ventilator-induced lung injury (VILI) and mortality when exposed to mechanical ventilation (MV). Yet, lack of a mechanical model describing UIP-lung deformation during MV represents a research gap. Aim of this study was to develop a constitutive mathematical model for UIP-lung deformation during lung protective MV based on the stress-strain behavior and the specific elastance of patients with EUIP as compared to that of acute respiratory distress syndrome (ARDS) and healthy lung. Partitioned lung and chest wall mechanics were assessed for patients with EUIP and primary ARDS (1:1 matched based on body mass index and PaO2/FiO2 ratio) during a PEEP trial performed within 24 h from intubation. Patient's stress-strain curve and the lung specific elastance were computed and compared with those of healthy lungs, derived from literature. Respiratory mechanics were used to fit a novel mathematical model of the lung describing mechanical-inflation-induced lung parenchyma deformation, differentiating the contributions of elastin and collagen, the main components of lung extracellular matrix. Five patients with EUIP and 5 matched with primary ARDS were included and analyzed. Global strain was not different at low PEEP between the groups. Overall specific elastance was significantly higher in EUIP as compared to ARDS (28.9 [22.8-33.2] cmH2O versus 11.4 [10.3-14.6] cmH2O, respectively). Compared to ARDS and healthy lung, the stress/strain curve of EUIP showed a steeper increase, crossing the VILI threshold stress risk for strain values greater than 0.55. The contribution of elastin was prevalent at lower strains, while the contribution of collagen was prevalent at large strains. The stress/strain curve for collagen showed an upward shift passing from ARDS and healthy lungs to EUIP lungs. During MV, patients with EUIP showed different respiratory mechanics, stress-strain curve and specific elastance as compared to ARDS patients and healthy subjects and may experience VILI even when protective MV is applied. According to our mathematical model of lung deformation during mechanical inflation, the elastic response of UIP-lung is peculiar and different from ARDS. Our data suggest that patients with EUIP experience VILI with ventilatory setting that are lung-protective for patients with ARDS.
Subject(s)
Lung , Respiration, Artificial , Respiratory Distress Syndrome , Humans , Male , Female , Middle Aged , Respiration, Artificial/adverse effects , Respiratory Distress Syndrome/physiopathology , Aged , Lung/physiopathology , Lung/pathology , Elasticity , Ventilator-Induced Lung Injury/physiopathology , Pulmonary Fibrosis/physiopathology , Pulmonary Fibrosis/metabolism , Respiratory Mechanics/physiology , Stress, Mechanical , Lung Diseases, Interstitial/physiopathology , Models, TheoreticalABSTRACT
BACKGROUND: Tracheostomy-related acquired pressure injuries (TRPIs) are one of the hospital-acquired conditions. We hypothesize that an uneven ventilator circuit load, leading to non-neutral tracheostomy tube positioning in the immediate post-tracheostomy period, leads to an increased incidence of TRPIs. Does switching the ventilator circuit load daily, in addition to standard post-tracheostomy care, lead to a decreased incidence of TRPIs? METHODS: This is a prospective quality improvement study. Study was conducted at two academic hospital sites within tertiary care hospitals at Emory University in different ICUs. Consecutive patients undergoing bedside percutaneous tracheostomy by the interventional pulmonary service were included. The flip the ventilator circuit (FLIC) protocol was designed and implemented in selected ICUs, with other ICUs as controls. RESULTS: Incidence of TRPI in intervention and control group were recorded at post-tracheostomy day 5. A total of 99 patients were included from October 22, 2019, to May 22, 2020. Overall, the total incidence of any TRPI was 23% at post-tracheostomy day 5. Incidence of stage I, stage II, and stages III-IV TRPIs at postoperative day 5 was 11%, 12%, and 0%, respectively. There was a decrease in the rate of skin breakdown in patients following the FLIC protocol when compared with standard of care (13% vs. 36%; p = 0.01). In a multivariable analysis, interventional group had decreased odds of developing TRPI (odds ratio, 0.32; 95% CI, 0.11-0.92; p = 0.03) after adjusting for age, albumin, body mass index, diabetes mellitus, and days in hospital before tracheostomy. CONCLUSIONS: The incidence of TRPIs within the first week following percutaneous tracheostomy is high. Switching the side of the ventilator circuit to evenly distribute load, in addition to standard bundled tracheostomy care, may decrease the overall incidence of TRPIs.
Subject(s)
Pressure Ulcer , Tracheostomy , Humans , Tracheostomy/adverse effects , Tracheostomy/methods , Tracheostomy/instrumentation , Male , Female , Prospective Studies , Middle Aged , Aged , Pressure Ulcer/prevention & control , Pressure Ulcer/etiology , Pressure Ulcer/epidemiology , Incidence , Respiration, Artificial/adverse effects , Quality Improvement , Intensive Care Units , Ventilators, Mechanical/adverse effectsABSTRACT
INTRODUCTION: Ventilator-associated pneumonia (VAP) is associated with increased mortality, prolonged mechanical ventilation, and longer intensive care unit stays. The rate of VAP (VAPs per 1000 ventilator days) within a hospital is an important quality metric. Despite adoption of preventative strategies, rates of VAP in injured patients remain high in trauma centers. Here, we report variation in risk-adjusted VAP rates within a statewide quality collaborative. METHODS: Using Michigan Trauma Quality Improvement Program data from 35 American College of Surgeons-verified Level I and Level II trauma centers between November 1, 2020 and January 31, 2023, a patient-level Poisson model was created to evaluate the risk-adjusted rate of VAP across institutions given the number of ventilator days, adjusting for injury severity, physiologic parameters, and comorbid conditions. Patient-level model results were summed to create center-level estimates. We performed observed-to-expected adjustments to calculate each center's risk-adjusted VAP days and flagged outliers as hospitals whose confidence intervals lay above or below the overall mean. RESULTS: We identified 538 VAP occurrences among a total of 33,038 ventilator days within the collaborative, with an overall mean of 16.3 VAPs per 1000 ventilator days. We found wide variation in risk-adjusted rates of VAP, ranging from 0 (0-8.9) to 33.0 (14.4-65.1) VAPs per 1000 d. Several hospitals were identified as high or low outliers. CONCLUSIONS: There exists significant variation in the rate of VAP among trauma centers. Investigation of practices and factors influencing the differences between low and high outlier institutions may yield information to reduce variation and improve outcomes.
Subject(s)
Pneumonia, Ventilator-Associated , Quality Improvement , Trauma Centers , Humans , Pneumonia, Ventilator-Associated/epidemiology , Pneumonia, Ventilator-Associated/prevention & control , Pneumonia, Ventilator-Associated/etiology , Michigan/epidemiology , Male , Female , Middle Aged , Trauma Centers/statistics & numerical data , Adult , Risk Adjustment/methods , Aged , Respiration, Artificial/statistics & numerical data , Respiration, Artificial/adverse effectsABSTRACT
BACKGROUND: Critical illness requiring invasive mechanical ventilation can precipitate important functional disability, contributing to multidimensional morbidity following admission to an intensive care unit (ICU). Early in-bed cycle ergometry added to usual physiotherapy may mitigate ICU-acquired physical function impairment. METHODS: We randomly assigned 360 adult ICU patients undergoing invasive mechanical ventilation to receive 30 minutes of early in-bed Cycling + Usual physiotherapy (n=178) or Usual physiotherapy alone (n=182). The primary outcome was the Physical Function ICU Test-scored (PFIT-s) at 3 days after discharge from the ICU (the score ranges from 0 to 10, with higher scores indicating better function). RESULTS: Cycling began within a median (interquartile range) of 2 (1 to 3) days of starting mechanical ventilation; patients received 3 (2 to 5) cycling sessions for a mean (±standard deviation) of 27.2 ± 6.6 minutes. In both groups, patients started Usual physiotherapy within 2 (2 to 4) days of mechanical ventilation and received 4 (2 to 7) Usual physiotherapy sessions. The duration of Usual physiotherapy was 23.7 ± 15.1 minutes in the Cycling + Usual physiotherapy group and 29.1 ± 13.2 minutes in the Usual physiotherapy group. No serious adverse events occurred in either group. Among survivors, the PFIT-s at 3 days after discharge from the ICU was 7.7 ± 1.7 in the Cycling + Usual physiotherapy group and 7.5 ± 1.7 in the Usual physiotherapy group (absolute difference, 0.23 points; 95% confidence interval, -0.19 to 0.65; P=0.29). CONCLUSIONS: Among adults receiving mechanical ventilation in the ICU, adding early in-bed Cycling to usual physiotherapy did not improve physical function at 3 days after discharge from the ICU compared with Usual physiotherapy alone. Cycling did not cause any serious adverse events. (Funded by the Canadian Institutes of Health Research and others; ClinicalTrials.gov numbers, NCT03471247 [full randomized clinical trial] and NCT02377830 [CYCLE Vanguard 46-patient internal pilot].).
Subject(s)
Critical Illness , Intensive Care Units , Physical Therapy Modalities , Respiration, Artificial , Humans , Respiration, Artificial/adverse effects , Female , Male , Middle Aged , Aged , Critical Illness/therapy , Ergometry/methods , AdultABSTRACT
BACKGROUND: Serum lactate dehydrogenase (LDH) is a nonspecific inflammatory biomarker and has been reported to be associated with pneumonia prognosis. This study aimed to evaluate the relationship between LDH levels and ventilator-associated pneumonia (VAP) risk in intensive care unit (ICU) patients. METHODS: This retrospective cohort study used data from the Multiparameter Intelligent Monitoring in Intensive Care database from 2001 to 2019. ICU patients aged ≥ 18 years and receiving mechanical ventilation were included. LDH levels were analyzed as continuous and categorical variables (< 210, 210-279, 279-390, > 390 IU/L), respectively. Restricted cubic spline (RCS) curves and quartiles were used to categorize LDH levels. Logistic regression and linear regression were utilized to assess the relationship of LDH levels with VAP risk and duration of mechanical ventilation, respectively. RESULTS: A total of 9,164 patients were enrolled, of which 646 (7.05%) patients developed VAP. High levels of LDH increased the risk of VAP [odds ratio (OR) = 1.15, 95% confidence interval (CI): 1.06-1.24] and LDH levels were positively correlated with the duration of mechanical ventilation [ß = 4.49, 95%CI: (3.42, 5.56)]. Moreover, patients with LDH levels of 279-390 IU/L (OR = 1.38, 95%CI: 1.08-1.76) and > 390 IU/L (OR = 1.50, 95%CI: 1.18-1.90) had a higher risk of VAP than patients with LDH levels < 210 IU/L. Patients with LDH levels of 279-390 IU/L [ß = 3.84, 95%CI: (0.86, 6.82)] and > 390 IU/L [ß = 11.22, 95%CI: (8.21, 14.22)] (vs. <210 IU/L) had a longer duration of mechanical ventilation. CONCLUSION: Elevated serum LDH levels were related to a higher risk of VAP and longer duration of mechanical ventilation and may be useful for monitoring VAP risk.