Prediction of Patient Length of Stay on the Intensive Care Unit Following Cardiac Surgery: A Logistic Regression Analysis Based on the Cardiac Operative Mortality Risk Calculator, EuroSCORE.

OBJECTIVE: The aim of this study was to develop a statistical model based on patient parameters to predict the length of stay (LOS) in the intensive care unit (ICU) following cardiac surgery in a single center. DESIGN: Data were collected from patients admitted to the ICU following cardiac surgery over a 10-year period (2006-2016). Both the additive and logistic EuroSCORE were calculated, and logistic regression analysis was carried out to formulate a model relating the predicted LOS to the EuroSCORE. This model was used to stratify patients into short stay (less than 48 hours) or long stay (more than 48 hours). SETTING: ICU at Papworth Hospital, Cambridgeshire. PARTICIPANTS: A total of 18,377 consecutive patients who had been in ICU following cardiac surgery (coronary graft bypass surgery, valve surgery, or a combination of both). INTERVENTIONS: This was an observational study. MEASUREMENTS AND MAIN RESULTS: The authors have shown that both the additive and logistic EuroSCORE can be used to stratify cardiac surgical patients in various predicted LOS in ICU. Further adjustments can be made to increase the number of patients correctly identified as either short stay or long stay. Comparison of the model predictions to the data demonstrated a high overall accuracy of 79.77%, and receiver operating characteristic curve analysis showed the area under the curve to be 0.7296. CONCLUSION: This analysis of an extensive data set shows that patient LOS in ICU after cardiac surgery in a single center can be predicted accurately using the simple cardiac operative risk scoring tool EuroSCORE. Using such predictions has the potential to improve ICU resource management

The Effects of Escalation of Respiratory Support and Prolonged Invasive Ventilation on Outcomes of Cardiac Surgical Patients: A Retrospective Cohort Study

Abstract Objectives: The aim of this study was to determine the effects of escalation of respiratory support and prolonged postoperative invasive ventilation on patient–centered outcomes, and identify perioperative factors associated with these two respiratory complications. Design: A retrospective cohort analysis of cardiac surgical patients admitted to cardiothoracic intensive care unit (ICU) between August 2015 and January 2018. Escalation of respiratory support was defined as ‘unplanned continuous positive airway pressure’, ‘non-invasive ventilation’ or ‘reintubation’ following surgery; prolonged invasive ventilation was defined as ‘invasive ventilation beyond the first 12 hours following surgery’. The primary endpoint was the composite of escalation of respiratory support and prolonged ventilation. Setting: Tertiary cardiothoracic ICU. Participants: A total of 2,098 patients were included and analyzed. Interventions: None. Measurements and Main Results: The composite of escalation of support or prolonged ventilation occurred in 509 patients (24.3%). Patients who met the composite had higher mortality (2.9% vs 0.1%; P<0.001) and longer median [interquartile range] length of ICU (2.1 [1.0–4.9] vs 0.9 [0.8–1.0] days; P<0.0001) and hospital (10.6 [8.0–16.0] vs 7.2 [6.2–10.0] days; P<0.0001) stay. Hypoxemia and anemia on admission to ICU were the only two factors independently associated with need for escalation of respiratory support or prolonged invasive ventilation. Conclusions: Escalation of respiratory support or prolonged invasive ventilation are frequently seen in cardiac surgery patients, and are highly associated with increased mortality and morbidity. Hypoxemia and anemia on admission to ICU are potentially modifiable factors associated with escalation of respiratory support or prolonged invasive ventilation.ACM is supported by a Clinical Research Career Development Fellowship from the Wellcome Trust (WT 2055214/Z/16/Z). VZ is supported by an Academic Clinical Fellowship from the National Institute for Health Research (ACF-2016-09-011)

Increasing frailty is associated with higher prevalence and reduced recognition of delirium in older hospitalised inpatients: results of a multi-centre study

Purpose: Delirium is a neuropsychiatric disorder delineated by an acute change in cognition, attention, and consciousness. It is common, particularly in older adults, but poorly recognised. Frailty is the accumulation of deficits conferring an increased risk of adverse outcomes. We set out to determine how severity of frailty, as measured using the CFS, affected delirium rates, and recognition in hospitalised older people in the United Kingdom. Methods: Adults over 65 years were included in an observational multi-centre audit across UK hospitals, two prospective rounds, and one retrospective note review. Clinical Frailty Scale (CFS), delirium status, and 30-day outcomes were recorded. Results: The overall prevalence of delirium was 16.3% (483). Patients with delirium were more frail than patients without delirium (median CFS 6 vs 4). The risk of delirium was greater with increasing frailty [OR 2.9 (1.8–4.6) in CFS 4 vs 1–3; OR 12.4 (6.2–24.5) in CFS 8 vs 1–3]. Higher CFS was associated with reduced recognition of delirium (OR of 0.7 (0.3–1.9) in CFS 4 compared to 0.2 (0.1–0.7) in CFS 8). These risks were both independent of age and dementia. Conclusion: We have demonstrated an incremental increase in risk of delirium with increasing frailty. This has important clinical implications, suggesting that frailty may provide a more nuanced measure of vulnerability to delirium and poor outcomes. However, the most frail patients are least likely to have their delirium diagnosed and there is a significant lack of research into the underlying pathophysiology of both of these common geriatric syndromes

Blunted perception of neural respiratory drive and breathlessness in patients with cystic fibrosis

The electromyogram recorded from the diaphragm (EMGdi) and parasternal intercostal muscle using surface electrodes (sEMGpara) provides a measure of neural respiratory drive (NRD), the magnitude of which reflects lung disease severity in stable cystic fibrosis. The aim of this study was to explore perception of NRD and breathlessness in both healthy individuals and patients with cystic fibrosis. Given chronic respiratory loading and increased NRD in cystic fibrosis, often in the absence of breathlessness at rest, we hypothesised that patients with cystic fibrosis would be able to tolerate higher levels of NRD for a given level of breathlessness compared to healthy individuals during exercise. 15 cystic fibrosis patients (mean forced expiratory volume in 1 s (FEV1) 53.5% predicted) and 15 age-matched, healthy controls were studied. Spirometry was measured in all subjects and lung volumes measured in the cystic fibrosis patients. EMGdi and sEMGpara were recorded at rest and during incremental cycle exercise to exhaustion and expressed as a percentage of maximum (% max) obtained from maximum respiratory manoeuvres. Borg breathlessness scores were recorded at rest and during each minute of exercise. EMGdi % max and sEMGpara % max and associated Borg breathlessness scores differed significantly between healthy subjects and cystic fibrosis patients at rest and during exercise. The relationship between EMGdi % max and sEMGpara % max and Borg score was shifted to the right in the cystic fibrosis patients, such that at comparable levels of EMGdi % max and sEMGpara % max the cystic fibrosis patients reported significantly lower Borg breathlessness scores compared to the healthy individuals. At Borg score 1 (clinically significant increase in breathlessness from baseline) corresponding levels of EMGdi % max (20.2±12% versus 32.15±15%, p=0.02) and sEMGpara % max (18.9±8% versus 29.2±15%, p=0.04) were lower in the healthy individuals compared to the cystic fibrosis patients. In the cystic fibrosis patients EMGdi % max at Borg score 1 was related to the degree of airways obstruction (FEV1) (r=−0.664, p=0.007) and hyperinflation (residual volume/total lung capacity) (r=0.710, p=0.03). This relationship was not observed for sEMGpara % max. These data suggest that compared to healthy individuals, patients with cystic fibrosis can tolerate much higher levels of NRD before increases in breathlessness from baseline become clinically significant. EMGdi % max and sEMGpara % max provide physiological tools with which to elucidate factors underlying inter-individual differences in breathlessness perception

Measurement of parasternal intercostal electromyogram during an infective exacerbation in patients with cystic fibrosis

The parasternal intercostal muscle electromyogram (sEMGpara) is a measure of neural respiratory drive and reflects lung disease severity in stable cystic fibrosis (CF). The aim of the study was to measure sEMGpara in acute infective exacerbations of CF and compare changes in sEMGpara with those in conventional lung function measures.12 patients with CF admitted to hospital with an acute chest infection were studied.There was a significant reduction in mean +/- sD sEMGpara (Delta sEMGpara -38+/-19%, p&lt;0.001) between admission and discharge. Spirometery also improved significantly from admission to discharge; Delta forced expiratory volume in 1 s % predicted 39+/-30%, p&lt;0.001 and Delta vital capacity % pred 22+/-18%, p&lt;0.001.sEMGpara has potential value as a nonvolitional measure of change in respiratory function in CF.</p