Extracellular vesicle Cystatin C and CD14 are associated with both renal dysfunction and heart failure

AIMS

Extracellular vesicles (EVs) are small double-membrane plasma vesicles that play key roles in cellular crosstalk and mechanisms such as inflammation. The role of EVs in combined organ failure such as cardiorenal syndrome has not been investigated. The aim of this study is to identify EV proteins that are associated with renal dysfunction, heart failure, and their combination in dyspnoeic patients.

METHODS AND RESULTS

Blood samples were prospectively collected in 404 patients presenting with breathlessness at the emergency department at National University Hospital, Singapore. Renal dysfunction was defined as estimated glomerular filtration rate < 60 mL/min/1.73 m² . The presence of heart failure was independently adjudicated by two clinicians on the basis of the criteria of the European Society of Cardiology guidelines. Protein levels of SerpinG1, SerpinF2, Cystatin C, and CD14 were measured with a quantitative immune assay within three EV sub-fractions and in plasma and were tested for their associations with renal dysfunction, heart failure, and the concurrence of both conditions using multinomial regression analysis, thereby correcting for confounders such as age, gender, ethnicity, and co-morbidities. Renal dysfunction was found in 92 patients (23%), while heart failure was present in 141 (35%). In total, 58 patients (14%) were diagnosed with both renal dysfunction and heart failure. Regression analysis showed that Cystatin C was associated with renal dysfunction, heart failure, and their combination in all three EV sub-fractions and in plasma. CD14 was associated with both renal dysfunction and the combined renal dysfunction and heart failure in all EV sub-fractions, and with presence of heart failure in the high density lipoprotein sub-fraction. SerpinG1 and SerpinF2 were associated with heart failure in, respectively, two and one out of three EV sub-fractions and in plasma, but not with renal dysfunction.

CONCLUSIONS

We provide the first data showing that Cystatin C and CD14 in circulating EVs are associated with both renal dysfunction and heart failure in patients presenting with acute dyspnoea. This suggests that EV proteins may be involved in the combined organ failure of the cardiorenal syndrome and may represent possible targets for prevention or treatment.

Prediction models for development of retinopathy in people with type 2 diabetes: systematic review and external validation in a Dutch primary care setting

AIMS/HYPOTHESIS

The aims of this study were to identify all published prognostic models predicting retinopathy risk applicable to people with type 2 diabetes, to assess their quality and accuracy, and to validate their predictive accuracy in a head-to-head comparison using an independent type 2 diabetes cohort.

METHODS

A systematic search was performed in PubMed and Embase in December 2019. Studies that met the following criteria were included: (1) the model was applicable in type 2 diabetes; (2) the outcome was retinopathy; and (3) follow-up was more than 1 year. Screening, data extraction (using the checklist for critical appraisal and data extraction for systemic reviews of prediction modelling studies [CHARMS]) and risk of bias assessment (by prediction model risk of bias assessment tool [PROBAST]) were performed independently by two reviewers. Selected models were externally validated in the large Hoorn Diabetes Care System (DCS) cohort in the Netherlands. Retinopathy risk was calculated using baseline data and compared with retinopathy incidence over 5 years. Calibration after intercept adjustment and discrimination (Harrell's C statistic) were assessed.

RESULTS

Twelve studies were included in the systematic review, reporting on 16 models. Outcomes ranged from referable retinopathy to blindness. Discrimination was reported in seven studies with C statistics ranging from 0.55 (95% CI 0.54, 0.56) to 0.84 (95% CI 0.78, 0.88). Five studies reported on calibration. Eight models could be compared head-to-head in the DCS cohort (N = 10,715). Most of the models underestimated retinopathy risk. Validating the models against different severities of retinopathy, C statistics ranged from 0.51 (95% CI 0.49, 0.53) to 0.89 (95% CI 0.88, 0.91).

CONCLUSIONS/INTERPRETATION

Several prognostic models can accurately predict retinopathy risk in a population-based type 2 diabetes cohort. Most of the models include easy-to-measure predictors enhancing their applicability. Tailoring retinopathy screening frequency based on accurate risk predictions may increase the efficiency and cost-effectiveness of diabetic retinopathy care.

REGISTRATION

PROSPERO registration ID CRD42018089122.

Anaesthesia geriatric evaluation to guide patient selection for preoperative multidisciplinary team care in cardiac surgery

BACKGROUND

A multidisciplinary approach to improve postoperative outcomes in frail elderly patients is gaining interest. Multidisciplinary team care should be targeted at complex patients at high risk for adverse postoperative outcome to limit the strain on available resources and to prevent an unnecessary increase in patient burden. This study aimed to improve patient selection for multidisciplinary care by identifying risk factors for disability after cardiac surgery in elderly patients.

METHODS

This was a two-centre prospective cohort study of 537 patients aged ≥70 yr undergoing elective cardiac surgery. Before surgery, 11 frailty characteristics were investigated. Outcome was disability at 3 months defined as World Health Organization Disability Assessment Schedule 2.0 ≥25%. Multivariable modelling using logistic regression, concordance statistic (c-statistic), and net reclassification index was used to identify factors contributing to patient selection.

RESULTS

Disability occurred in 91 (17%) patients. Ten out of 11 frailty characteristics were associated with disability. A multivariable model, including the European System for Cardiac Operative Risk Evaluation II and preoperative haemoglobin, yielded a c-statistic of 0.71 (95% confidence interval [CI]: 0.66-0.77). After adding pre-specified frailty characteristics (polypharmacy, gait speed, physical disability, preoperative health-related quality of life, and living alone) to this model, the c-statistic improved to 0.78 (95% CI: 0.73-0.83). The net reclassification index was 0.32 (P<0.001), showing improved discrimination for patients at risk for disability at 3 months.

CONCLUSIONS

The addition of preoperative frailty characteristics to a multivariable model improved discrimination between elderly patients with and without disability at 3 months after cardiac surgery, and can be used to guide patient selection for preoperative multidisciplinary team care.

CLINICAL TRIAL REGISTRATION

NCT02535728.

Patient and anesthesia characteristics of children with low pre-incision blood pressure: A retrospective observational study

BACKGROUND

Intraoperative blood pressure has been suggested as a key factor for safe pediatric anesthesia. However, there is not much insight into factors that discriminate between children with low and normal pre-incision blood pressure. Our aim was to explore whether children who have a low blood pressure during anesthesia are different than those with normal blood pressure. The focus of the present study was on the pre-incision period.

METHODS

This retrospective study included pediatric patients undergoing anesthesia for non-cardiac surgery at a tertiary pediatric university hospital, between 2012 and 2016. We analyzed the association between pre-incision blood pressure and patient- and anesthesia characteristics, comparing low with normal pre-incision blood pressure. This association was further explored with a multivariable linear regression.

RESULTS

In total, 20 962 anesthetic cases were included. Pre-incision blood pressure was associated with age (beta -0.04 SD per year), gender (female -0.11), previous surgery (-0.15), preoperative blood pressure (+0.01 per mm Hg), epilepsy (0.12), bronchial hyperactivity (-0.18), emergency surgery (0.10), loco-regional technique (-0.48), artificial airway device (supraglottic airway device instead of tube 0.07), and sevoflurane concentration (0.03 per sevoflurane %).

CONCLUSIONS

Children with low pre-incision blood pressure do not differ on clinically relevant factors from children with normal blood pressure. Although the present explorative study shows that pre-incision blood pressure is partly dependent on patient characteristics and partly dependent on anesthetic technique, other unmeasured variables might play a more important role.

Incorporating repeated measurements into prediction models in the critical care setting: a framework, systematic review and meta-analysis

BACKGROUND

The incorporation of repeated measurements into multivariable prediction research may greatly enhance predictive performance. However, the methodological possibilities vary widely and a structured overview of the possible and utilized approaches lacks. Therefore, we [1] propose a structured framework for these approaches, [2] determine what methods are currently used to incorporate repeated measurements in prediction research in the critical care setting and, where possible, [3] assess the added discriminative value of incorporating repeated measurements.

METHODS

The proposed framework consists of three domains: the observation window (static or dynamic), the processing of the raw data (raw data modelling, feature extraction and reduction) and the type of modelling. A systematic review was performed to identify studies which incorporate repeated measurements to predict (e.g. mortality) in the critical care setting. The within-study difference in c-statistics between models with versus without repeated measurements were obtained and pooled in a meta-analysis.

RESULTS

From the 2618 studies found, 29 studies incorporated multiple repeated measurements. The annual number of studies with repeated measurements increased from 2.8/year (2000-2005) to 16.0/year (2016-2018). The majority of studies that incorporated repeated measurements for prediction research used a dynamic observation window, and extracted features directly from the data. Differences in c statistics ranged from - 0.048 to 0.217 in favour of models that utilize repeated measurements.

CONCLUSIONS

Repeated measurements are increasingly common to predict events in the critical care domain, but their incorporation is lagging. A framework of possible approaches could aid researchers to optimize future prediction models.

The intermediate care unit as a cost-reducing critical care facility in tertiary referral hospitals: a single-centre observational study

OBJECTIVES

To determine whether and to what extent the surgical intermediate care unit (IMCU) reduces healthcare costs.

DESIGN

Retrospective cohort study.

SETTING

The mixed-surgical IMCU of a tertiary academic referral hospital.

PARTICIPANTS

All admissions (n=2577) from 2012 to 2015.

PRIMARY AND SECONDARY OUTCOME MEASURES

The outcome measure was the hypothetical cost savings due to the presence of the IMCU. For this, each admission day was classified as either low-acuity or high-acuity, based on the Therapeutic Intervention Scoring System-28, the required specific nursing interventions and the indication for admission at the IMCU. Costs (2018) used were €463 per hospital ward, €1307 per IMCU and €2224 per intensive care unit (ICU) admission day. Savings were calculated by subtracting the actual IMCU costs from the hypothetical costs in the absence of the IMCU.

RESULTS

There were 9037 admission days (n=2577 admissions) at the IMCU. The proportion of high-acuity admissions was 87.6%. Total costs at the IMCU were €11.808 888. Total hypothetical costs in absence of the IMCU were €18.115 284. Total cost savings were thus €6.306 395, or €1.576 599, per year.

CONCLUSIONS

The surgical IMCU may substantially reduce societal healthcare costs, making it a cost saving alternative to ICU care. Constant adequate triage is essential to optimise its potential.

Effect of cytomegalovirus reactivation on the time course of systemic host response biomarkers in previously immunocompetent critically ill patients with sepsis: a matched cohort study

BACKGROUND

Cytomegalovirus (CMV) reactivation in previously immunocompetent critically ill patients is associated with increased mortality, which has been hypothesized to result from virus-induced immunomodulation. Therefore, we studied the effects of CMV reactivation on the temporal course of host response biomarkers in patients with sepsis.

METHODS

In this matched cohort study, each sepsis patient developing CMV reactivation between day 3 and 17 (CMV+) was compared with one CMV seropositive patient without reactivation (CMVs+) and one CMV seronegative patient (CMVs-). CMV serostatus and plasma loads were determined by enzyme-linked immunoassays and real-time polymerase chain reaction, respectively. Systemic interleukin-6 (IL-6), IL-8, IL-18, interferon-gamma-induced protein-10 (IP-10), neutrophilic elastase, IL-1 receptor antagonist (RA), and IL-10 were measured at five time points by multiplex immunoassay. The effects of CMV reactivation on sequential concentrations of these biomarkers were assessed in multivariable mixed models.

RESULTS

Among 64 CMV+ patients, 45 could be matched to CMVs+ or CMVs- controls or both. The two baseline characteristics and host response biomarker levels at viremia onset were similar between groups. CMV+ patients had increased IP-10 on day 7 after viremia onset (symmetric percentage difference +44% versus -15% when compared with CMVs+ and +37% versus +4% when compared with CMVs-) and decreased IL-1RA (-41% versus 0% and -49% versus +10%, respectively). However, multivariable analyses did not show an independent association between CMV reactivation and time trends of IL-6, IP-10, IL-10, or IL-1RA.

CONCLUSION

CMV reactivation was not independently associated with changes in the temporal trends of host response biomarkers in comparison with non-reactivating patients. Therefore, these markers should not be used as surrogate clinical endpoints for interventional studies evaluating anti-CMV therapy.

Pulmonary Embolism After Endovascular Aortic Repair, a Retrospective Cohort Study

OBJECTIVES

Endovascular aortic repair (EVAR) is associated with an increased risk of pulmonary embolism, which is often clinically silent and therefore difficult to recognise. The aim was to investigate the incidence of pulmonary embolism after EVAR using routinely performed pre- and post-operative aortic computed tomography angiography (CTA), and the association between pulmonary embolism and mortality.

METHODS

This single centre retrospective cohort study included adult patients who underwent EVAR in the University Medical Centre Utrecht between January 2010 and July 2015 and who had a total aortic, thoracic aortic, or pulmonary CTA within one month post-operatively. Baseline and mortality data were obtained by reviewing hospital and general practitioner records. The primary outcome was pulmonary embolism within one month after surgery. Secondary outcomes were 30 day and six month mortality.

RESULTS

During the study period, 526 EVARs were performed. Seventy-four of these procedures were included in the analysis of which there were 40 thoracic and 34 abdominal EVARs. In nine patients (12%, 95% CI 7-22) pulmonary embolism was observed of which one was central, two were segmental, and six were subsegmental. Seven were clinically silent and two were present on the pre-operative CTA. Thirty day mortality was significantly higher in patients with pulmonary embolism (relative risk 14.4, 95% CI 1.4-143, p = .037) though none of the deaths seemed directly attributable to it.

CONCLUSIONS

This study, although preliminary, suggests that silent pulmonary embolism after EVAR occurs in approximately one in 10 patients, despite routine thrombo-embolism prophylaxis. Pulmonary embolism was associated with a higher 30 day mortality risk yet it was not the cause of death in any of these patients.

Optimizing critical care of the trauma patient at the intermediate care unit: a cost-efficient approach

Background

The aim of this study was to describe the case load, safety, and cost savings of critical care of the trauma patient provided at the surgical intermediate care unit (IMCU).

Methods

This cohort study included all trauma admissions between January 1, 2011 and January 7, 2015 at the general intensive care unit (ICU), stand-alone neuro(surgical) IMCU, and stand-alone (trauma) surgical IMCU. Trauma mechanism, Abbreviated Injury Scale score and Injury Severity Score (ISS), vital signs, laboratory parameters, admission duration, intubation duration, ICU transfer, and in-hospital mortality were prospectively collected. Hypothetical cost savings were calculated using the fixed cost price per IMCU (US$1500) and ICU (US$2500) admission day.

Results

A total of 1320 admissions were included, 675 (51.1%) at the IMCU and 645 (48.9%) at the ICU. Patients admitted at the IMCU had a median ISS of 17 (11, 22). Their median duration of admission was 32.8 hours (18.8, 62.5). At the IMCU, one patient died due to aneurogenic shock. A subsequent ICU transfer was required in 38 (5.6%) IMCU admissions. Of these transfers, four patients died due to neurological deterioration. At the ICU, the median ISS was 22 (14, 30). Nearly all (n=620, 96.3%) ICU trauma patients required mechanical ventilation. Expected total cost savings due to the presence of the IMCU were US$1 772 785.

Discussion

A substantial amount of trauma patients in need of critical care can safely be admitted at the IMCU, without the need for further mechanical ventilation. Thereby, the IMCU could fulfill an essential cost-saving role in the management of severely injured trauma patients.

Level of evidence

Level IV.

Joint management format at the mixed-surgical intermediate care unit: an interrupted time series analysis

Background

The management format of the mixed-surgical intermediate care unit (IMCU) affects its performance. A format of combined supervision of surgeons with additional critical care certifications and admitting specialists, named the “joint format”, may herein be a promising new model of specialized critical care. This study aims to assess the performance of the joint management format.

Methods

This observational cohort study compared three IMCU management formats at the stand-alone, mixed-surgical IMCU of a tertiary referral hospital using interrupted time series analyses. All admissions from 2001 until 2015 were included. Predetermined criteria for performance (utilization, efficiency, and safety) were applied to three different management format periods: open (2001–2006), closed (2006–2011), and joint (2011–2015) formats.

Results

A total of 8894 admissions were analyzed. In terms of case load (utilization), there was an overall increase in the number of surgical patients (0.25%/year) (p<0.001), age (0.38/year) (p<0.001), and readmissions from the ward (0.16%/year) (p<0.001) and from the intensive care unit (ICU) (0.17%/year) (p=0.014). In terms of efficiency, the admission duration decreased (1.58 hours/year) (p<0.001). Transfer to the ICU within 24  hours, readmission within 24  hours from the ward, and unplanned mortality (eg, safety) did not change over time.

Discussion

At a time of increasingly complex case load, the joint format at the mixed-surgical IMCU is an efficient and safe management format in which the admitting specialist continues to provide specialized care. Specialty-specific supervision at IMCUs is a safe option which should be considered in healthcare policy decisions.

Level of evidence

Level IV.

Causes and prevention of postoperative myocardial injury

Over the past few years non-cardiac surgery has been recognised as a serious circulatory stress test which may trigger cardiovascular events such as myocardial infarction, in particular in patients at high risk. Detection of these postoperative cardiovascular events is difficult as clinical symptoms often go unnoticed. To improve detection, guidelines advise to perform routine postoperative assessment of cardiac troponin. Troponin elevation - or postoperative myocardial injury - can be caused by myocardial infarction. However, also non-coronary causes, such as cardiac arrhythmias, sepsis and pulmonary embolism, may play a role in a considerable number of patients with postoperative myocardial injury. It is crucial to acquire more knowledge about the underlying mechanisms of postoperative myocardial injury because effective prevention and treatment options are lacking. Preoperative administration of beta-blockers, aspirin, statins, clonidine, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers, and preoperative revascularisation have all been investigated as preventive options. Of these, only statins should be considered as the initiation or reload of statins may reduce the risk of postoperative myocardial injury. There is also not enough evidence for intraoperative measures such blood pressure optimisation or intensified medical therapy once patients have developed postoperative myocardial injury. Given the impact, better preoperative identification of patients at risk of postoperative myocardial injury, for example using preoperatively measured biomarkers, would be helpful to improve cardiac optimisation.

Assessment of the intermediate care unit triage system

BACKGROUND

An important critique with respect to the utilization of intermediate care units (IMCU) is that they potentially admit patients who would otherwise be cared for on the regular ward. This would lead to an undesired waste of critical care resources. This article aims to (1) describe the caseload at the IMCU and (2) to assess the triage system at the IMCU to determine potentially unnecessary admissions.

METHODS

This cohort study included all admissions at the mixed-surgical IMCU from 2001 to 2015. The Therapeutic Intervention Scoring System-28 (TISS-28) was prospectively collected for all admissions to describe the caseload at the IMCU and to identify medical criteria for admission. These were combined with logistical criteria to assess the IMCU triage system.

RESULTS

A total of 8816 admissions were included in the study. The average TISS-28 was 20.19 (95% CI 18.05 to 22.33), corresponding with 3.57 (95% CI 3.19 to 3.94) hours of direct patient-related work per patient per nursing shift. Over time, this increased by an average of 0.27 points/year (p<0.001). Of all admissions, 6539 (74.2%) were medically considered to be justly admitted, and 7093 (80.4%) were logistically considered to be justly admitted. With these criteria combined, a total of 8324 (94.4%) were correctly admitted.

DISCUSSION

Most admissions to the IMCU are medically and/or logistically necessary, as the majority of admitted patients demand a higher level of nursing care than available on the general ward. Continuous triage is thereby essential. These findings support further utilization of the IMCU in our current healthcare system and has important implications for IMCU-related management decisions.

LEVEL OF EVIDENCE

Level VI.

Accuracy of remote continuous respiratory rate monitoring technologies intended for low care clinical settings: a prospective observational study

Purpose

Altered respiratory rate (RR) has been identified as an important predictor of serious adverse events during hospitalization. Introduction of a well-tolerated continuous RR monitor could potentially reduce serious adverse events such as opioid-induced respiratory depression. The purpose of this study was to investigate the ability of different monitor devices to detect RR in low care clinical settings.

Methods

This was a prospective method-comparison study with a cross-sectional design. Thoracic impedance pneumography (IPG), frequency modulated continuous wave radar, and an acoustic breath sounds monitor were compared with the gold standard of capnography for their ability to detect RR in breaths per minute (breaths·min⁻¹) in awake postoperative patients in the postanesthesia care unit. The Bland and Altman method for repeated measurements and mixed effect modelling was used to obtain bias and limits of agreement (LoA). Furthermore, the ability of the three devices to assist with correct treatment decisions was evaluated in Clarke Error Grids.

Results

Twenty patients were monitored for 1,203 min, with a median [interquartile range] of 61 [60-63] min per patient. The bias (98.9% LoA) were 0.1 (−7.9 to 7.9) breaths·min⁻¹ for the acoustic monitor, −1.6 (−10.8 to 7.6) for the radar, and −1.9 (−13.1 to 9.2) for the IPG. The extent to which the monitors guided adequate or led to inadequate treatment decisions (determined by Clarke Error Grid analysis) differed significantly between the monitors (P = 0.011). Decisions were correct 96% of the time for acoustic, 95% of the time for radar, and 94% of the time for IPG monitoring devices.

Conclusions

None of the studied devices (acoustic, IPG, and radar monitor) had LoA that were within our predefined (based on clinical judgement) limits of ± 2 breaths·min⁻¹. The acoustic breath sound monitor predicted the correct treatment more often than the IPG and the radar device.

Electronic supplementary material

The online version of this article (10.1007/s12630-018-1214-z) contains supplementary material, which is available to authorized users.

Validation of the VitalPAC Early Warning Score at the Intermediate Care Unit

AIM

To assess the performance and clinical relevance of the Early Warning Scoring (EWS) system at the Intermediate Care Unit (IMCU).

METHODS

This cohort study used all the VitalPAC EWS (ViEWS) scores collected during each nursing shift from 2014 through 2016 at the mixed surgical IMCU of an academic teaching hospital. Clinical deterioration defined as transfer to the Intensive Care Unit (ICU) or mortality within 24 h was the primary outcome of interest.

RESULTS

A total of 9113 aggregated ViEWS scores were obtained from 2113 admissions. The incidence of the combined outcome was 272 (3.0%). The area under the curve of the ViEWS was 0.72 (CI: 0.69-0.75). Using a threshold value of six, the sensitivity was 68% with a positive predictive value of 5% and a number needed to trigger (e.g., false alarms) of 19%.

CONCLUSION

The ViEWS at the IMCU has a discriminative performance that is considerably lower than at the hospital ward. The number of false alarms is high, which may result in alarm fatigue. Therefore, use of the ViEWS in its current form at the IMCU should be reconsidered.

Cardiac events within one year after a subarachnoid haemorrhage: The predictive value of troponin elevation after aneurysm occlusion

BACKGROUND

Patients who survive after an aneurysmal subarachnoid haemorrhage (ASAH) have an increased incidence of cardiovascular events compared with the general population. We assessed whether troponin elevation after aneurysm occlusion, as marker of myocardial injury, can predict long-term cardiac events.

METHODS

We analysed a prospectively collected cohort of 159 patients with ASAH and early aneurysm occlusion, in whom routine post-intervention troponin I (TnI) measurements were performed. With competing risk regression modelling we estimated the association between TnI elevation after aneurysm occlusion and major adverse cardiac events within one year. Secondary outcome measures were all-cause mortality and neurological condition within one year. The predictive value of post-intervention TnI was compared with the predictive value of pre-intervention characteristics using c-statistics and the integrated discrimination improvement index.

RESULTS

Subdistribution hazard ratios for TnI elevation and major adverse cardiac events at one year were 1.05 (95% confidence interval (CI) 1.03-1.07) per 10 ng/l increase in TnI and 7.91 (95% CI 1.46-43.0) for any TnI elevation. After adjustment for pre-intervention variables, the subdistribution hazard ratios were 1.47 (95% CI 0.81-2.67) per 10 ng/l and 9.00 (95% CI 1.62-50.1) for any elevation. The c-statistic was 0.71 for TnI elevation as a continuous measure and 0.69 for any TnI elevation. The integrated discrimination improvement index showed a minimum improvement in prediction of 0.08 (interquartile range 0.06 to 0.09) for TnI as a continuous measure and 0.003 (interquartile range -0.004 to 0.01) for any TnI elevation, when compared with pre-intervention characteristics.

CONCLUSION

TnI elevation after occlusion of a ruptured intracranial aneurysm predicts the occurrence of a major adverse cardiac event within one year after ASAH.

Acute Brain Dysfunction: Development and Validation of a Daily Prediction Model

BACKGROUND

The goal of this study was to develop and validate a dynamic risk model to predict daily changes in acute brain dysfunction (ie, delirium and coma), discharge, and mortality in ICU patients.

METHODS

Using data from a multicenter prospective ICU cohort, a daily acute brain dysfunction-prediction model (ABD-pm) was developed by using multinomial logistic regression that estimated 15 transition probabilities (from one of three brain function states [normal, delirious, or comatose] to one of five possible outcomes [normal, delirious, comatose, ICU discharge, or died]) using baseline and daily risk factors. Model discrimination was assessed by using predictive characteristics such as negative predictive value (NPV). Calibration was assessed by plotting empirical vs model-estimated probabilities. Internal validation was performed by using a bootstrap procedure.

RESULTS

Data were analyzed from 810 patients (6,711 daily transitions). The ABD-pm included individual risk factors: mental status, age, preexisting cognitive impairment, baseline and daily severity of illness, and daily administration of sedatives. The model yielded very high NPVs for "next day" delirium (NPV: 0.823), coma (NPV: 0.892), normal cognitive state (NPV: 0.875), ICU discharge (NPV: 0.905), and mortality (NPV: 0.981). The model demonstrated outstanding calibration when predicting the total number of patients expected to be in any given state across predicted risk.

CONCLUSIONS

We developed and internally validated a dynamic risk model that predicts the daily risk for one of three cognitive states, ICU discharge, or mortality. The ABD-pm may be useful for predicting the proportion of patients for each outcome state across entire ICU populations to guide quality, safety, and care delivery activities.

The incidence of postoperative respiratory complications: A retrospective analysis of cuffed vs uncuffed tracheal tubes in children 0-7 years of age

BACKGROUND

The use of cuffed vs uncuffed endotracheal tubes in pediatric anesthesia is widely debated. This study aimed to investigate whether the use of cuffed vs uncuffed tubes is associated with an increased incidence of acute postoperative respiratory complications.

METHODS

We retrospectively studied all children aged 0-7 years in which the trachea was intubated between September 28, 2006 and August 26, 2016 in a pediatric university hospital. Logistic regression analysis was performed to estimate the association between tube design (cuffed vs uncuffed) and the incidence of acute postoperative respiratory complications (stridor, wheezing, or dyspnea; desaturations ≤90%) in need of intervention (epinephrine, dexamethasone, nebulizers, supplementary oxygen, or reintubation), adjusting for potential confounders.

RESULTS

In 5247 of 6796 cases (77%), a cuffed tube was used. Acute postoperative respiratory complications in need of intervention occurred in 334 cases (4.9%) and were less common after cuffed than after uncuffed tubes (N = 236, 4.5% vs N = 98, 6.3%, respectively, odds ratio 0.70; 95%CI 0.55-0.89). Desaturation occurred less often after cuffed tubes (cuffed: N = 1365, 26.0%; uncuffed: N = 512, 33.1%; OR: 0.71 (0.61-0.84)). After adjusting for confounders, there was no difference in acute postoperative respiratory complications between cuffed tubes and uncuffed tubes (OR 0.74; 95%CI 0.55-1.01). Subgroup analyses in various age groups did not show significant differences between the use of cuffed or uncuffed tubes.

CONCLUSION

After adjustment for multiple confounders, the use of cuffed tubes was not associated with an increased incidence of acute respiratory complications in postanesthesia care unit.

The association between aortic cross clamp time and postoperative morbidity and mortality in mitral valve repair: a retrospective cohort study

BACKGROUND

The aim of this study was to estimate the association between aortic cross clamp time and postoperative morbidity and mortality in patients undergoing mitral valve repair.

METHODS

A retrospective cohort study between 2006 and 2014 was performed as a single Center study in the University Medical Center Utrecht. In total 1007 patients who underwent mitral valve repair were included. The patients were divided into a group who underwent isolated mitral valve repair and a group who underwent mitral valve repair with concomitant intervention(s). The primary endpoint was a composite consisting of in-hospital mortality or postoperative major complications.

RESULTS

In the isolated mitral valve group (N.=405), patients were significantly younger, healthier and had fewer complications (9.9%). Patients with concomitant intervention(s) had a twofold higher rate of postoperative complications and mortality (18.1%). After adjustment for confounding there was no association between aortic cross clamp time and the primary endpoint in both the isolated mitral valve group (odds ratio 1.04; 95% CI: 0.98-1.11) and the group with concomitant interventions (odds ratio 1.02; 95% CI: 0.97-1.06).

CONCLUSIONS

In patients undergoing mitral valve repair surgery a longer aortic cross clamp time was not associated with postoperative complications and mortality. The higher postoperative morbidity and mortality in combined procedures appears to be due to a higher age, more comorbidities and an extra intervention rather than to the duration of aortic cross clamp time.