Outcomes of Patients With Prolonged Intensive Care Unit Length of Stay After Cardiac Surgery

Variation in risk-adjusted cardiac intensive care unit (CICU) length of stay and the association with in-hospital mortality: An analysis from the Critical Care Cardiology Trials Network (CCCTN) registry

BACKGROUND

Previous studies have suggested that there is wide variability in cardiac intensive care unit (CICU) length of stay (LOS); however, these studies are limited by the absence of detailed risk assessment at the time of admission. Thus, we evaluated inter-hospital differences in CICU LOS, and the association between LOS and in-hospital mortality.

METHODS

Using data from the Critical Care Cardiology Trials Network (CCCTN) registry, we included 22,862 admissions between 2017 and 2022 from 35 primarily tertiary and quaternary CICUs that captured consecutive admissions in annual 2-month snapshots. The primary analysis compared inter-hospital differences in CICU LOS, as well as the association between CICU LOS and all-cause in-hospital mortality using a Fine and Gray competing risk model.

RESULTS

The overall median CICU LOS was 2.2 (1.1-4.8) days, and the median hospital LOS was 5.9 (2.8-12.3) days. Admissions in the longest tertile of LOS tended to be younger with higher rates of pre-existing comorbidities, and had higher Sequential Organ Failure Assessment (SOFA) scores, as well as higher rates of mechanical ventilation, intravenous vasopressor use, mechanical circulatory support, and renal replacement therapy. Unadjusted all-cause in-hospital mortality was 9.3%, 6.7%, and 13.4% in the lowest, intermediate, and highest CICU LOS tertiles. In a competing risk analysis, individual patient CICU LOS was correlated (r2 = 0.31) with a higher risk of 30-day in-hospital mortality. The relationship remained significant in admissions with heart failure, ST-elevation myocardial infarction and non-ST segment elevation myocardial infarction.

CONCLUSIONS

In a large registry of academic CICUs, we observed significant variation in CICU LOS and report that LOS is independently associated with all-cause in-hospital mortality. These findings could potentially be used to improve CICU resource utilization planning and refine risk prognostication in critically ill cardiovascular patients.

Intraoperative use of cell saver devices decreases the rate of hyperlactatemia in patients undergoing cardiac surgery

Objective

This study was aimed to elucidate the effect of the intraoperative cell saver (CS) on hyperlactatemia of patients who underwent cardiac surgery.

Design

A sub-analysis of the CS was performed, which is a historial control trial of patients undergoing cardiac surgery.

Setting

This was a retrospective single-center and not blinded study.

Participants

We examined the occurrence of hyperlactatemia retrospectively in patients of CS group (n = 78) who were included in prospective trial and received valvular surgery, where CS was used during the procedure. Patients subjected to valvular surgery before February 2021 were adopted in control group (n = 79).

Interventions

Arterial blood was sampled (1) before cardiopulmonary bypass, (2) during bypass (3) immediately after bypass, (4) on ICU admission and (5) every 4 h up to 24 h postoperatively.

Measurements and main results

A lower incidence of hyperlactatemia (32.1% vs. 57.0%; P = 0.001) was observed in patients from the CS group. Furthermore, the blood lactate concentration was higher in control group than in CS group during CPB, post CPB, on ICU admission and lasted until 20 h after the operation. Multivariable analysis revealed that intraoperative use of CS was expected to be a protective factor against hyperlactatemia in this study (OR = 0.31, 95% CI 0.15-0.63, P = 0.001).

Conclusion

Intraoperative use of a CS device was associated with a lower incidence of hyperlactatemia. Whether such device use is valuable to limiting hyperlactatemia in cardiac patients after surgery requires further evaluation in larger prospective studies.

Remote ischemic preconditioning and clinical outcomes after pediatric cardiac surgery: a systematic review and meta-analysis

BACKGROUND

The benefit of remote ischemia preconditioning (RIPreC) in pediatric cardiac surgery is unclear. The objective of this systematic review and meta-analysis was to examine the effectiveness of RIPreC in reducing the duration of mechanical ventilation and intensive care unit (ICU) length of stay after pediatric cardiac surgery.

METHODS

We searched PubMed, EMBASE and the Cochrane Library from inception to December 31, 2022. Randomized controlled trials comparing RIPreC versus control in children undergoing cardiac surgery were included. The risk of bias of included studies was assessed using the Risk of Bias 2 (RoB 2) tool. The outcomes of interest were postoperative duration of mechanical ventilation and ICU length of stay. We conducted random-effects meta-analysis to calculate weighted mean difference (WMD) with 95% confidence interval (CI) for the outcomes of interest. We performed sensitivity analysis to examine the influence of intraoperative propofol use.

RESULTS

Thirteen trials enrolling 1,352 children were included. Meta-analyses of all trials showed that RIPreC did not reduce postoperative duration of mechanical ventilation (WMD -5.35 h, 95% CI -12.12-1.42) but reduced postoperative ICU length of stay (WMD -11.48 h, 95% CI -20.96- -2.01). When only trials using propofol-free anesthesia were included, both mechanical ventilation duration (WMD -2.16 h, 95% CI -3.87- -0.45) and ICU length of stay (WMD -7.41 h, 95% CI -14.77- -0.05) were reduced by RIPreC. The overall quality of evidence was moderate to low.

CONCLUSIONS

The effects of RIPreC on clinical outcomes after pediatric cardiac surgery were inconsistent, but both postoperative mechanical ventilation duration and ICU length of stay were reduced in the subgroup of children not exposed to propofol. These results suggested a possible interaction effect of propofol. More studies with adequate sample size and without intraoperative propofol use are needed to define the role of RIPreC in pediatric cardiac surgery.

Outcomes of Prolonged ICU Stay for Patients Undergoing Cardiac Surgery in Australia and New Zealand

OBJECTIVE

To determine the effect of intensive care unit (ICU) length of stay (LOS) on hospital mortality and non-home discharge for patients undergoing cardiac surgery over a 16-year period in Australia and New Zealand.

DESIGN

A retrospective, multicenter cohort study covering the period January 1, 2004 to December 31, 2019.

SETTING

One hundred one hospitals in Australia and New Zealand that submitted data to the Australia New Zealand Intensive Care Society Adult Patient Database.

PARTICIPANTS

Adult patients (aged >18) who underwent coronary artery bypass grafting, valve surgery, or combined valve + coronary artery surgery.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The authors analyzed 252,948 cardiac surgical patients from 101 hospitals, with a median age of 68.3 years (IQR 60-75.5), of whom 74.2% (187,632 of 252,948) were male patients. A U-shaped relationship was observed between ICU LOS and hospital mortality, with significantly elevated mortality at short (<20 hours) and long (>5 days) ICU LOS, which persisted after adjustment for illness severity and across clinically important subgroups (odds ratio for mortality with ICU LOS >5 days = 3.21, 95% CI 2.88-3.58, p < 0.001).

CONCLUSIONS

Prolonged duration of ICU LOS after cardiac surgery is associated with increased hospital mortality in a U-shaped relationship. An ICU LOS >5 days should be considered a meaningful definition for prolonged ICU stay after cardiac surgery.

Preoperative frailty based on laboratory data and postoperative health outcomes in patients undergoing coronary artery bypass graft surgery

BACKGROUND

Frailty is associated with adverse surgical outcomes. Patients with cardiovascular diseases have many risk factors of frailty; thus, preoperative frailty evaluation is necessary to predict adverse outcomes after coronary artery bypass graft (CABG) surgery. Laboratory data based-frailty assessments are objective and not time-consuming, addressing the need for an accurate but simple frailty screening for patients awaiting CABG surgery.

OBJECTIVES

This retrospective study aimed to determine the association between laboratory based-frailty and patient health outcomes after CABG surgery.

METHODS

We evaluated 896 patients who underwent on-pump or off-pump CABG surgery between August 1, 2015 and July 31, 2020 at a tertiary hospital. The frailty index-laboratory (FI-LAB), which comprises 32 laboratory parameters and vital signs, was used for frailty assessment.

RESULTS

The patients were divided into three groups according to their preoperative FI-LAB level as low (FI-LAB <0.25, 23.0%), moderate (FI-LAB ≥0.25 to ≤0.4, 54.9%), and high (FI-LAB>0.4, 22.1%) frailty groups. In the confounder-adjusted analysis, the lengths of hospital stay and intensive care unit stay were longer by 2.20 days (p=.023) and by 0.89 days (p=.009), respectively, in the high frailty group than those in the low frailty group. The odds ratio for 30-day readmission was also 2.58 times higher in the high frailty group than that in the low frailty group.

CONCLUSION

A high preoperative FI-LAB score indicates increasing risks of adverse postoperative outcomes among CABG surgery patients. FI-LAB has potential strengths to capture the need for a more thorough frailty assessment for cardiac surgery patients.

Prediction of Prolonged Intensive Care Unit Length of Stay Following Cardiac Surgery

Intensive care unit (ICU) costs comprise a significant proportion of the total inpatient charges for cardiac surgery. No reliable method for predicting intensive care unit length of stay following cardiac surgery exists, making appropriate staffing and resource allocation challenging. We sought to develop a predictive model to anticipate prolonged ICU length of stay (LOS). All patients undergoing coronary artery bypass grafting (CABG) and/or valve surgery with a Society of Thoracic Surgeons (STS) predicted risk score were evaluated from an institutional STS database. Models were developed using 2014-2017 data; validation used 2018-2019 data. Prolonged ICU LOS was defined as requiring ICU care for at least three days postoperatively. Predictive models were created using lasso regression and relative utility compared. A total of 3283 patients were included with 1669 (50.8%) undergoing isolated CABG. Overall, 32% of patients had prolonged ICU LOS. Patients with comorbid conditions including severe COPD (53% vs 29%, P < 0.001), recent pneumonia (46% vs 31%, P < 0.001), dialysis-dependent renal failure (57% vs 31%, P < 0.001) or reoperative status (41% vs 31%, P < 0.001) were more likely to experience prolonged ICU stays. A prediction model utilizing preoperative and intraoperative variables correctly predicted prolonged ICU stay 76% of the time. A preoperative variable-only model exhibited 74% prediction accuracy. Excellent prediction of prolonged ICU stay can be achieved using STS data. Moreover, there is limited loss of predictive ability when restricting models to preoperative variables. This novel model can be applied to aid patient counseling, resource allocation, and staff utilization.

Increased mast cell density is associated with decreased fibrosis in human atrial tissue

Fibrotic remodelling of the atria is poorly understood and can be regulated by myocardial immune cell populations after injury. Mast cells are resident immune sentinel cells present in the heart that respond to tissue damage and have been linked to fibrosis in other settings. The role of cardiac mast cells in fibrotic remodelling in response to human myocardial injury is controversial. In this study, we sought to determine the association between mast cells, atrial fibrosis, and outcomes in a heterogeneous population of cardiac surgical patients, including a substantial proportion of coronary artery bypass grafting patients. Atrial appendage from patients was assessed for collagen and mast cell density by histology and by droplet digital polymerase chain reaction (ddPCR) for mast cell associated transcripts. Clinical variables and outcomes were also followed. Mast cells were detected in human atrial tissue at varying densities. Histological and ddPCR assessment of mast cells in atrial tissue were closely correlated. Patients with high mast cell density had less fibrosis and lower severity of heart failure classification or incidence mortality than patients with low mast cell content. Analysis of a homogeneous population of coronary artery bypass graft patients yielded similar observations. Therefore, evidence from this study suggests that increased atrial mast cell populations are associated with decreased clinical cardiac fibrotic remodelling and improved outcomes, in cardiac surgery patients.

A Nomogram for Predicting Long Length of Stay in The Intensive Care Unit in Patients Undergoing CABG: Results From the Multicenter E-CABG Registry

OBJECTIVE

Many papers evaluated predictive factors for prolonged intensive care unit (ICU) stay after cardiac surgery, but efforts in translating those models in practical clinical tools is lacking. The aim of this study was to build a new nomogram score and test its calibration and discrimination power for predicting a long length of stay in the ICU among patients undergoing coronary artery bypass graft surgery (CABG).

DESIGN

Retrospective analysis of an international registry.

SETTING

Multicentric.

PARTICIPANTS

Based on the european multicenter study on coronary artery bypass grafting (E-CABG) registry (NCT02319083), a total of 7,352 consecutive patients who underwent isolated CABG were analyzed.

INTERVENTIONS

A "long length of stay" in the ICU was considered when equal to or more than 3 days. Predictive factors were analyzed through a multivariate logistic regression model that was used for the nomogram.

RESULTS

Long length of ICU stay was observed in 2,665 patients (36.2%). Ten independent variables were included in the final regression model: the SYNTAX score class critical preoperative state, left ventricular ejection fraction class, angina at rest, poor mobility, recent potent antiplatelet use, estimated glomerular filtration rate class, body mass index, sex, and age. Based on this 10-risk factors logistic regression model, a nomogram has been designed.

CONCLUSION

The authors defined a nomogram model that can provide an individual prediction of long length of ICU stay in cardiovascular surgical patients undergoing CABG. This type of model would allow an early recognition of high-risk patients who might receive different preoperative and postoperative treatments to improve outcomes.

The effect of therapeutic drug monitoring of beta-lactam and fluoroquinolones on clinical outcome in critically ill patients: the DOLPHIN trial protocol of a multi-centre randomised controlled trial

BACKGROUND

Critically ill patients undergo extensive physiological alterations that will have impact on antibiotic pharmacokinetics. Up to 60% of intensive care unit (ICU) patients meet the pharmacodynamic targets of beta-lactam antibiotics, with only 30% in fluoroquinolones. Not reaching these targets might increase the chance of therapeutic failure, resulting in increased mortality and morbidity, and antibiotic resistance. The DOLPHIN trial was designed to demonstrate the added value of therapeutic drug monitoring (TDM) of beta-lactam and fluoroquinolones in critically ill patients in the ICU.

METHODS

A multi-centre, randomised controlled trial (RCT) was designed to assess the efficacy and cost-effectiveness of model-based TDM of beta-lactam and fluoroquinolones. Four hundred fifty patients will be included within 24 months after start of inclusion. Eligible patients will be randomly allocated to either study group: the intervention group (active TDM) or the control group (non-TDM). In the intervention group dose adjustment of the study antibiotics (cefotaxime, ceftazidime, ceftriaxone, cefuroxime, amoxicillin, amoxicillin with clavulanic acid, flucloxacillin, piperacillin with tazobactam, meropenem, and ciprofloxacin) on day 1, 3, and 5 is performed based upon TDM with a Bayesian model. The primary outcome will be ICU length of stay. Other outcomes amongst all survival, disease severity, safety, quality of life after ICU discharge, and cost effectiveness will be included.

DISCUSSION

No trial has investigated the effect of early TDM of beta-lactam and fluoroquinolones on clinical outcome in critically ill patients. The findings from the DOLPHIN trial will possibly lead to new insights in clinical management of critically ill patients receiving antibiotics. In short, to TDM or not to TDM?

TRIAL REGISTRATION

EudraCT number: 2017-004677-14. Sponsor protocol name: DOLPHIN. Registered 6 March 2018 . Protocol Version 6, Protocol date: 27 November 2019.

Survival, Quality of Life, and Functional Status Following Prolonged ICU Stay in Cardiac Surgical Patients: A Systematic Review

OBJECTIVES

Compared with noncardiac critical illness, critically ill postoperative cardiac surgical patients have different underlying pathophysiologies, are exposed to different processes of care, and thus may experience different outcome trajectories. Our objective was to systematically review the outcomes of cardiac surgical patients requiring prolonged intensive care with respect to survival, residential status, functional recovery, and quality of life in both hospital and long-term follow-up.

DATA SOURCES

MEDLINE, Embase, CINAHL, Web of Science, and Dissertations and Theses Global up to July 21, 2017.

STUDY SELECTION

Studies were included if they assessed hospital or long-term survival and/or patient-centered outcomes in adult patients with prolonged ICU stays following major cardiac surgery. After screening 10,159 citations, 114 articles were reviewed in full; a final 34 articles met criteria for data extraction.

DATA EXTRACTION

Two reviewers independently extracted data and assessed risk of bias using the National Institutes of Health Quality Assessment Tool for Observational Studies. Extracted data included the used definition of prolonged ICU stay, number and characteristics of prolonged ICU stay patients, and any comparator short stay group, length of follow-up, hospital and long-term survival, residential status, patient-centered outcome measure used, and relevant score.

DATA SYNTHESIS

The definition of prolonged ICU stay varied from 2 days to greater than 14 days. Twenty-eight studies observed greater in-hospital mortality among all levels of prolonged ICU stay. Twenty-five studies observed greater long-term mortality among all levels of prolonged ICU stay. Multiple tools were used to assess patient-centered outcomes. Long-term health-related quality of life and function was equivalent or worse with prolonged ICU stay.

CONCLUSIONS

We found consistent evidence that patients with increases in ICU length of stay beyond 48 hours have significantly increasing risk of hospital and long-term mortality. The significant heterogeneity in exposure and outcome definitions leave us unable to precisely quantify the risk of prolonged ICU stay on mortality and patient-centered outcomes.

Prognosis of patients with acute respiratory failure and prolonged intensive care unit stay

Background

Reasons for the prolonged critical care support include uncertainty of outcome, the complex dynamic created between physicians with care team members and the patient's family over a general unwillingness to surrender to unfavorable outcomes. The purpose of this study was to investigate outcomes and identify risk factors of patients with acute respiratory failure (ARF) who required a prolonged intensive care unit (ICU) stay (≥21 days). It may provide reference to screen patients who are suitable for hospice care.

Methods

The medical records of all ARF patients with a prolonged ICU stay were retrospectively reviewed. The primary outcome was in-hospital mortality.

Results

We identified 1,189 patients. Sepsis (n=896, 75.4%) was the most common cause of prolonged ICU stays, following by renal failure (n=232, 19.5%), and unstable hemodynamic status vasopressors or arrhythmia (n=208, 17.5%). Using multivariable logistic regression, we identified eight risk factors of death: age >75 years, ICU stay for more than 28 days, APACHE II score ≥25, unstable hemodynamic status, renal failure, hepatic failure, massive gastrointestinal tract bleeding, and using a fraction of inspired oxygen (FiO₂) ≥40%. The overall in-hospital mortality rate was 53.6% (n=637), and it up to 75.3% (216/287) for patients with at least three risk factors.

Conclusions

The outcome of patients with ARF who required prolonged ICU stay was poor. They had a high risk of in-hospital mortality. Palliative care should be considered as a reasonable option for the patients at high risk of death.

Predictors of extubation failure after open-chest cardiac surgery based on routinely collected data. The importance of a shared interprofessional clinical assessment

BACKGROUND

Extubation failure (ExtF) is associated with prolonged hospital length of stay and mortality in adult cardiac surgery patients postoperatively. In this population, ExtF-related variables such as the arterial partial pressure of oxygen to fraction of inspired oxygen ratio (PaO₂/FiO₂), rapid shallow breathing index, cough strength, endotracheal secretions and neurological function have been sparsely researched.

AIM

To identify variables that are predictive of ExtF and related outcomes.

METHOD

Prospective observational longitudinal study. Consecutively presenting patients ( n=205) undergoing open-heart cardiac surgery and admitted to the Cardiosurgical Intensive Care Unit (CICU) were recruited. The clinical data were collected at CICU admission and immediately prior to extubation. ExtF was defined as the need to restart invasive or non-invasive mechanical ventilation while the patient was in the CICU.

RESULTS

The ExtF incidence was 13%. ExtF related significantly to hospital mortality, CICU length of stay and total hospital length of stay. The risk of ExtF decreased significantly, by 93% in patients with good neurological function and by 83% in those with a Rapid Shallow Breathing Index of ≥57 breaths/min per litre. Conversely, ExtF risk increased 27 times when the PaO₂/FiO₂ was <150 and 11 times when it was ≥450. Also, a reassuring PaO₂/FiO₂ value may hide critical pulmonary or extra-pulmonary conditions independent from alveolar function.

CONCLUSION

The decision to extubate patients should be taken after thoroughly discussing and combining the data derived from nursing and medical clinical assessments. Extubation should be delayed until the patient achieves safe respiratory, oxygenation and haemodynamic conditions, and good neurocognitive function.

[Analysis of mortality and hospital stay in cardiac surgery in Mexico 2015: Data from the National Cardiology Institute]

OBJECTIVE

To analyse hospital mortality in patients subjected to cardiac surgery in Mexico during the year 2015, and identify the mortality risks factors, and its correlation with days of hospital stay in the cardiovascular intensive care unit.

METHOD

The database of Cardiovascular Intensive Care of the National Institute of Cardiology was examined for this cases and controls study that included only adult patients subjected to cardiac surgery during the year 2015.

RESULTS

A total of 571 patients were subjected to a surgical procedure. The predominant indication was single or multiple valve replacement surgery, followed by coronary revascularisation surgery, and correction of adult congenital heart disease. Overall mortality was 9.2, and 8% died in intensive care. The main risk factors for death were preoperative organ failure or pulmonary hypertension, and prolonged time with extracorporeal circulation. The primary cause of death was secondary to cardiogenic shock. The hospital mortality observed in this population was higher for patients undergoing pulmonary thromboendarterectomy, complex aortic disease surgery, and valvular surgery.

CONCLUSIONS

The mortality of patients undergoing cardiac surgery in Mexico differs slightly from that reported in the world literature, primarily because there were more multivalvular surgeries and mixed complex procedures performed.

Post-ICU psychological morbidity in very long ICU stay patients with ARDS and delirium

PURPOSE

We investigated the impact of delirium on illness severity, psychological state, and memory in acute respiratory distress syndrome patients with very long ICU stay.

MATERIALS AND METHODS

Prospective cohort study in the medical-surgical ICUs of 2 teaching hospitals. Very long ICU stay (>75days) and prolonged delirium (≥40days) thresholds were determined by ROC analysis. Subjects were ≥18years, full-code, and provided informed consent. Illness severity was assessed using Acute Physiology and Chronic Health Evaluation IV, Simplified Acute Physiology Score-3, and Sequential Organ Failure Assessment scores. Psychological impact was assessed using the Hospital Anxiety and Depression Scale, Impact of Event Scale-Revised, and the 14-question Post-Traumatic Stress Syndrome (PTSS-14). Memory was assessed using the ICU Memory Tool survey.

RESULTS

181 subjects were included. Illness severity did not correlate with delirium duration. On logistic regression, only PTSS-14<49 correlated with delirium (p=0.001; 95% CI 1.011, 1.041). 49% remembered their ICU stay clearly. 47% had delusional memories, 50% reported intrusive memories, and 44% reported unexplained feelings of panic or apprehension.

CONCLUSION

Delirium was associated with memory impairment and PTSS-14 scores suggestive of PTSD, but not illness severity.

Association Between Hemogram Parameters and Survival of Critically Ill Patients

AIM

Recently, hemogram parameters, such as mean platelet volume (MPV), had been proposed as novel inflammatory and prognostic factors. In present retrospective analysis, we aimed to determine and compare MPV of survived and dead patients whom admitted to intensive care unit (ICU) of our institution.

METHODS

We recorded hemogram parameters and other laboratory data and demographic characteristics of patients treated in ICU. Patients are divided into 2 groups-dead patients and survived patients. Laboratory data of survived patients compared to those of dead patients.

RESULTS

Age, gender, and other laboratory variables were not significantly different between dead and survived patients. On the other hand, MPV of survived patients was significantly higher than that of the dead patients ( P = .001).

CONCLUSION

We think that elevated MPV levels in an ICU patient should alert clinicians for worse outcome. Physicians should be more careful in the management of these patients.