The effect of PD-L1 testing on the cost-effectiveness and economic impact of immune checkpoint inhibitors for the second-line treatment of NSCLC

BACKGROUND

Immune checkpoint inhibitors improve outcomes compared with chemotherapy in lung cancer. Tumor PD-L1 receptor expression is being studied as a predictive biomarker. The objective of this study was to assess the cost-effectiveness and economic impact of second-line treatment with nivolumab, pembrolizumab, and atezolizumab with and without the use of PD-L1 testing for patient selection.

DESIGN

We developed a decision-analytic model to determine the cost-effectiveness of PD-L1 assessment and second-line immunotherapy versus docetaxel. The model used outcomes data from randomized clinical trials (RCTs) and drug acquisition costs from the United States. Thereafter, we used epidemiologic data to estimate the economic impact of the treatment.

RESULTS

We included four RCTs (2 with nivolumab, 1 with pembrolizumab, and 1 with atezolizumab). The incremental quality-adjusted life year (QALY) for nivolumab was 0.417 among squamous tumors and 0.287 among non-squamous tumors and the incremental cost-effectiveness ratio (ICER) were $155 605 and $187 685, respectively. The QALY gain in the base case for atezolizumab was 0.354 and the ICER was $215 802. Compared with treating all patients, the selection of patients by PD-L1 expression improved incremental QALY by up to 183% and decreased the ICER by up to 65%. Pembrolizumab was studied only in patients whose tumors expressed PD-L1. The QALY gain was 0.346 and the ICER was $98 421. Patient selection also reduced the budget impact of immunotherapy.

CONCLUSION

The use of PD-L1 expression as a biomarker increases cost-effectiveness of immunotherapy but also diminishes the number of potential life-years saved.

Immune checkpoint inhibitors for advanced non-small cell lung cancer: emerging sequencing for new treatment targets

Lung cancer is the leading cause of cancer-related deaths in the world. Immune checkpoint inhibitors (ICI) stimulate cytotoxic lymphocyte activity against tumour cells. These agents are available for the treatment of non-small cell lung cancer (NSCLC) after failure of platinum-based therapy. One recent study has demonstrated that ICI monotherapy was superior to platinum-based chemotherapy for first-line treatment. Nevertheless, this benefit was only for a minority of the population (30%) whose tumour programmed death receptor ligand-1 (PD-L1) expression was above 50%. Therefore, several strategies are under investigation. One option for patients with PD-L1 expression lower than 50% may be the combination of ICI with platinum-based chemotherapy or with ICIs against different targets. However, all of these combinations are at an early stage of investigation and may be very expensive or toxic, producing several harmful adverse events.

Glial fibrillary acidic protein for the early diagnosis of intracerebral hemorrhage: Systematic review and meta-analysis of diagnostic test accuracy

Background and aims

Glial fibrillary acidic protein (GFAP) has shown promise in several studies for its ability to diagnose intracerebral hemorrhage (ICH). We evaluated the diagnostic accuracy of blood GFAP level to differentiate (ICH) from acute ischemic stroke (AIS) and stroke mimics, both overall, and in the first three hours after symptom onset.

Methods

We searched multiple databases, without language restriction, from inception until December 2017. Hierarchical summary receiver operating characteristic (HSROC) modeling was used to meta-analyze results. We conducted subgroup analyses restricted to blood samples collected within 0–60, 60–120, and 120–180 min time groups after symptom onset, to evaluate diagnostic accuracy in the early pre-hospital phase. Between and within study heterogeneity was explored using meta-regression.

Results

The search identified 199 potentially relevant citations from which 11 studies involving 1297 participants (350 ICH, 947 AIS, or mimic) were included. The pooled sensitivity, specificity, and area under the HSROC curve were 0.756 (95% CI 0.630–0.849), 0.945 (95% CI 0.858–0.980), and 0.904 (95% CI 0.878–0.931), respectively. Differences in assays used, but not the other covariates, partially explained between-study heterogeneity ( p = 0.034). The summary estimates for the 0–60, 60–120, and 120–180 min subgroups were comparable to the primary analysis and there was no statistically significant difference in diagnostic accuracy between subgroups.

Conclusions

GFAP is a promising diagnostic biomarker for ICH diagnosis in the early pre-hospital phase. Test accuracy is affected by assay subtype, but there are still unexplained sources of heterogeneity. High quality, international multi-center trials are warranted to develop and validate a point-of-care GFAP assay for the rapid triage and evaluation of acute stroke in the pre-hospital setting.

Machine Learning Outperforms Existing Clinical Scoring Tools in the Prediction of Postoperative Atrial Fibrillation During Intensive Care Unit Admission After Cardiac Surgery

OBJECTIVE(S)

Using the Medical Information Mart for Intensive Care III (MIMIC-III) database, we compared the performance of machine learning (ML) to the to the established gold standard scoring tool (POAF Score) in predicting postoperative atrial fibrillation (POAF) during intensive care unit (ICU) admission after cardiac surgery.

METHODS

Random forest classifier (RF), decision tree classifier (DT), logistic regression (LR), K neighbours classifier (KNN), support vector machine (SVM), and gradient boosted machine (GBM) were compared to the POAF Score. Cross-validation was used to assess the area under the receiver operating characteristic curve (AUC), sensitivity, and specificity of ML models. POAF Score performance confidence intervals were generated using 1,000 bootstraps. Risk profiles for GBM were generated using Shapley additive values.

RESULTS

A total of 6,349 ICU admissions encompassing 6,040 patients were included. POAF occurred in 1,364 of the 6,349 admissions (21.5%). For predicting POAF during ICU admission after cardiac surgery, GBM, LR, RF, KNN, SVM and DT achieved an AUC of 0.74 (0.71-0.77), 0.73 (0.71-0.75), 0.72 (0.69-0.75), 0.68 (0.67-0.69), 0.67 (0.66-0.68) and 0.59 (0.55-0.63) respectively. The POAF Score AUC was 0.63 (0.62-0.64). Shapley additive values analysis of GBM generated patient level explanations for each prediction.

CONCLUSION

Machine learning models based on readily available preoperative data can outperform clinical scoring tools for predicting POAF during ICU admission after cardiac surgery. Explanatory models are shown to have potential in personalising POAF risk profiles for patients by illustrating probabilistic input variable contributions. Future research is required to evaluate the clinical utility and safety of implementing ML-driven tools for POAF prediction.

Duration of post-operative antibiotic treatment in acute complicated appendicitis: systematic review and meta-analysis

BACKGROUND

Appendicitis is the most frequent aetiology of acute abdominal pain requiring surgical treatment, with an estimated lifetime risk between 7% and 8%. Antibiotics play a substantial role in treatment, and there is considerable debate regarding the duration of antibiotics in treating appendicitis.

METHODS

We searched multiple databases from inception until June 2019 for peer-reviewed studies that compared different durations of antibiotic treatment after appendicectomy for acute complicated appendicitis in adults. We dichotomized reported data into short- and extended-term antibiotic use and controlled for different definitional thresholds in the meta-analysis. We generated risk ratios using restricted maximum likelihood methods and mixed effects modelling for each outcome of interest.

RESULTS

Four observational studies involving 847 participants were included in the meta-analysis. For the primary outcomes of intra-abdominal infection, we did not find a statistically significant difference between extended- and short-term antibiotic strategies for intra-abdominal infection (Risk ratio 0.92, 95% confidence interval (CI) 0.49-1.74). Three randomized controlled trials involving 291 participants were included in a separate meta-analysis. We found that extended antibiotic usage was not associated with a statistically significant reduced risk for intra-abdominal infection (RR 0.52, 95% CI 0.21-1.29) or surgical site skin infection (RR 1.44, 95% CI 0.43-4.81).

CONCLUSION

This systematic review and meta-analysis found that extended post-operative antibiotic treatment may not be associated with a reduced risk of intra-abdominal infection; however, meta-analysis was significantly limited by heterogeneity between studies and underpowered trials. Further large randomized controlled trials are needed to confirm these findings.

Cost-effectiveness and budget impact of lung cancer immunotherapy in South America: strategies to improve access

AIM

Immune checkpoint inhibitors revolutionized the treatment of non-small-cell lung cancer, although their costs are a limitation.

METHODS

The number of patients with non-small-cell lung cancer eligible for immunotherapy was estimated using local epidemiology data. We extracted survival data from RCTs to estimate the life-years saved in a 5-year time horizon. All costs were in local prices converted to US dollars.

RESULTS

In the first-line, the budget impact of pembrolizumab decreased by 35% through risk-sharing. In the second-line, patient selection by programmed-death receptor ligand 1 expression decreased the budgetary impact by 45%, and improved cost-effectiveness. Immunotherapy was more cost-effective in the first-line.

CONCLUSION

Given current pricing, Immune checkpoint inhibitors are cost-prohibitive in the majority of South American health services. Nevertheless, several strategies should improve access to immunotherapy.

Transduction of ferret airway epithelia using a pre-treatment and lentiviral gene vector

Background

The safety and efficiency of gene therapies for cystic fibrosis (CF) need to be assessed in pre-clinical models. Using the normal ferret, this study sought to determine whether ferret airway epithelia could be transduced with a lysophosphatidylcholine (LPC) pre-treatment followed by a VSV-G pseudotyped HIV-1 based lentiviral (LV) vector, in preparation for future studies in CF ferrets.

Methods

Six normal ferrets (7 -8 weeks old) were treated with a 150 μL LPC pre-treatment, followed one hour later by a 500 μL LV vector dose containing the LacZ transgene. LacZ gene expression in the conducting airways and lung was assessed by X-gal staining after 7 days. The presence of transduction in the lung, as well as off-target transduction in the liver, spleen and gonads, were assessed by qPCR. The levels of LV vector p24 protein bio-distribution in blood sera were assessed by ELISA at 0, 1, 3, 5 and 7 days.

Results

The dosing protocol was well tolerated. LacZ gene expression was observed en face in the trachea of all animals. Histology showed that ciliated and basal cells were transduced in the trachea, with rare LacZ transduced single cells noted in lung. p24 levels was not detectable in the sera of 5 of the 6 animals. The LacZ gene was not detected in the lung tissue and no off-target transduction was detected by qPCR.

Conclusions

This study shows that ferret airway epithelia are transducible using our unique two-step pre-treatment and LV vector dosing protocol. We have identified a number of unusual anatomical factors that are likely to influence the level of transduction that can be achieved in ferret airways. The ability to transduce ferret airway epithelium is a promising step towards therapeutic LV-CFTR testing in a CF ferret model.

Perioperative Neutrophil-Lymphocyte Ratio Predicts Mortality After Cardiac Surgery: Systematic Review and Meta-Analysis

OBJECTIVES

Neutrophil-lymphocyte ratio (NLR) is an inflammatory biomarker that has been evaluated across a variety of surgical disciplines and is widely predictive of poor postoperative outcome, but its value in cardiac surgery is unclear. The authors did this systematic review and meta-analysis to determine the impact of elevated perioperative NLR on survival after cardiac surgery.

DESIGN

Systematic review and meta-analysis of study-level data.

SETTING

Multiple hospitals involved in an international pool of studies.

PARTICIPANTS

Adults undergoing cardiac surgery.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The authors searched multiple databases from inception until November 2020. They generated summary hazard ratios (HR) and odds ratios (OR) for the association of elevated preoperative NLR with long-term and short-term mortality following cardiac surgery. They separately reported on elevated postoperative NLR. Between-study heterogeneity was explored using metaregression. The authors included 12 studies involving 13,262 patients undergoing cardiac surgery. Elevated preoperative NLR was associated with worse long-term (>30 days) (hazard ratio [HR] 1.56; 95% CI [confidence interval], 1.18-2.06; 8 studies) and short-term (<30 days) mortality (OR 3.18; 95% CI, 1.90-5.30; 7 studies). One study reported the association of elevated postoperative NLR with long-term mortality (HR 8.58; 95% CI, 2.55-28.85). There was considerable between-study heterogeneity for the analysis of long-term mortality (I² statistic 94.39%), which mostly was explained by study-level variables, such as the number of variables adjusted for by included studies and how many of these significantly increased the risk of long-term mortality, high risk of bias, and number of study centers, as well as participant level factors, such as average participant age and hypertension prevalence.

CONCLUSIONS

Perioperative NLR is an independent predictor of short-term and long-term postoperative mortality following cardiac surgery. Further research is required to determine which patient-level factors modify the prognostic value of NLR and to evaluate its role in routine clinical practice.

Prognostic Significance of Preoperative Neutrophil-Lymphocyte Ratio in Vascular Surgery: Systematic Review and Meta-Analysis

OBJECTIVE

The global burden of surgical vascular disease is increasing and with it, the need for cost-effective, accessible prognostic biomarkers to aid optimization of peri-operative outcomes. The neutrophil-lymphocyte ratio (NLR) is emerging as a potential candidate biomarker for perioperative risk stratification. We therefore performed this systematic review and meta-analysis on the prognostic value of elevated preoperative NLR in vascular surgery.

METHODS

We searched Embase (Ovid), Medline (Ovid), and the Cochrane Library database from inception to June 2019. Screening was performed, and included all peer-reviewed original research studies reporting preoperative NLR in adult emergent and elective vascular surgical patients. Studies were assessed for bias and quality of evidence using a standardized tool. Meta-analysis was performed by general linear (mixed-effects) modelling where possible, and otherwise a narrative review was conducted. Between-study heterogeneity was estimated using the Chi-squared statistic and explored qualitatively.

RESULTS

Fourteen studies involving 5,652 patients were included. The overall methodological quality was good. Elevated preoperative NLR was associated with increased risk of long-term mortality (HR 1.40 [95%CI: 1.13-1.74], Chi-squared 60.3%, 7 studies, 3,637 people) and short-term mortality (OR: 3.08; 95%CI: 1.91-4.95), Chi-squared 66.59%, 4 studies, 945 people). Outcome measures used by fewer studies such as graft patency and amputation free survival were assessed via narrative review.

CONCLUSIONS

NLR is a promising, readily obtainable, prognostic biomarker for mortality outcomes following vascular surgery. Heterogeneity in patient factors, severity of vascular disease, and type of vascular surgery performed renders direct comparison of outcomes from the current literature challenging. This systematic review supports further investigation for NLR measurement in pre-vascular surgical risk stratification. In particular, the establishment of a universally accepted NLR cut-off value is of importance in real-world implementation of this biomarker.

The Prognostic Significance of Red Cell Distribution Width in Cardiac Surgery: A Systematic Review and Meta-Analysis

RED CELL DISTRIBUTION WIDTH (RDW) is a routinely available biomarker of likely erythropoietic dysfunction, which may be associated with adverse outcomes after cardiac surgery. This systematic review and meta-analysis aimed to clarify the prognostic value of RDW in patients undergoing cardiac surgery. The authors searched MEDLINE, Embase, and the Cochrane Library from inception to May 10, 2022 for studies investigating the association between elevated RDW (as defined by the authors of included studies) and adverse outcomes after cardiac surgery. Herein, the authors extracted maximally adjusted hazard ratios (HRs) and odds ratios (ORs) with associated CIs, and pooled them using random-effects inverse- variance modeling. The authors explored interstudy heterogeneity using metaregression. The authors included 26 studies involving 48,092 patients who had undergone cardiac surgery. Elevated preoperative RDW was associated with long-term mortality (pooled HR 1.63, 95% CI 1.05-2.52), short-term mortality (pooled OR 2.16, 95% CI 1.21-3.87), acute kidney injury (AKI; pooled OR 1.30, 95% CI 1.19-1.41) and postoperative atrial fibrillation (POAF; pooled OR 1.44, 95% CI 1.05-1.96). Some studies suggested a significant association between preoperative RDW elevation and neurologic complications; however, their number was insufficient for meta-analysis. The postoperative RDW levels were less consistently reported and could not be meta-analyzed. In conclusion, the authors found that elevated preoperative RDW was associated with increased short- and long-term mortality, POAF, and AKI after cardiac surgery. Further research is needed to investigate its role in the risk stratification of patients undergoing cardiac surgery.

Platelet Transfusion After Cardiac Surgery

OBJECTIVES

To investigate the independent association of platelet transfusion with hospital mortality and key relevant clinical outcomes in cardiac surgery.

DESIGN

A single-center, propensity score-matched, retrospective, cohort study.

SETTING

At an American tertiary teaching hospital data from the Medical Information Mart for Intensive Care III and IV databases from 2001 to 2019.

PARTICIPANTS

Consecutive adults undergoing coronary artery bypass graft and/or cardiac valvular surgery.

INTERVENTIONS

Platelet transfusion during perioperative intensive care unit (ICU) admission.

MEASUREMENTS AND MAIN RESULTS

Overall, 12,043 adults met the study inclusion criteria. Of these, 1,621 (13.5%) received apheresis-leukoreduced platelets, with a median of 1.19 units per recipient (IQR: 0.93-1.19) at a median of 1.78 hours (IQR: 0.75-4.25) after ICU admission. The platelet count was measured in 1,176 patients (72.5%) before transfusion, with a median count of 120 × 10⁹/L (IQR: 89.0-157.0), and only 53 (3.3%) had platelet counts below 50 × 10⁹/L. After propensity matching of 1,046 platelet recipients with 1,046 controls, perioperative platelet transfusion carried no association with in-hospital mortality (odds ratio [OR]: 1.28; 99% CI: 0.49-3.35; p = 0.4980). However, it was associated with a pattern of decreased odds of suspected infection (eg, respiratory infection, urinary tract infection, septicaemia, or other; OR: 0.70; 99% CI: 0.50-0.97; p = 0.0050), days in the hospital (adjusted mean difference [AMD]: 0.86; 99% CI: -0.27 to 1.98; p = 0.048), or days in intensive care (AMD 0.83; 99% CI: -0.15 to 1.82; p = 0.0290).

CONCLUSIONS

Platelet transfusion was not associated with hospital mortality, but it was associated with decreased odds of suspected infection and with shorter ICU and hospital stays.

The prognostic value of elevated neutrophil-lymphocyte ratio for cardiac surgery-associated acute kidney injury: A systematic review and meta-analysis

BACKGROUND

Patients undergoing cardiac surgery are at significant risk of developing postoperative acute kidney injury (AKI). Neutrophil-lymphocyte ratio (NLR) is a widely available inflammatory biomarker which may be of prognostic value in this setting.

METHODS

We conducted a systematic review and meta-analysis of studies reporting associations between perioperative NLR with postoperative AKI. We searched Medline, Embase and the Cochrane Library, without language restriction, from inception to May 2022 for relevant studies. We meta-analysed the reported odds ratios (ORs) with 95% confidence intervals (CIs) for both elevated preoperative and postoperative NLR with risk of postoperative AKI and need for renal replacement therapy (RRT). We conducted a meta-regression to explore inter-study statistical heterogeneity.

RESULTS

Twelve studies involving 10,724 participants undergoing cardiac surgery were included, with eight studies being deemed at high risk of bias using PROBAST modelling. We found statistically significant associations between elevated preoperative NLR and postoperative AKI (OR 1.45, 95% CI 1.18-1.77), as well as postoperative need for RRT (OR 2.37, 95% CI 1.50-3.72). Postoperative NLR measurements were not of prognostic significance.

CONCLUSIONS

Elevated preoperative NLR is a reliable inflammatory biomarker for predicting AKI following cardiac surgery.

Elevated Cardiac Troponin to Detect Acute Cellular Rejection After Cardiac Transplantation: A Systematic Review and Meta-Analysis

Cardiac troponin is well known as a highly specific marker of cardiomyocyte damage, and has significant diagnostic accuracy in many cardiac conditions. However, the value of elevated recipient troponin in diagnosing adverse outcomes in heart transplant recipients is uncertain. We searched MEDLINE (Ovid), Embase (Ovid), and the Cochrane Library from inception until December 2020. We generated summary sensitivity, specificity, and Bayesian areas under the curve (BAUC) using bivariate Bayesian modelling, and standardised mean differences (SMDs) to quantify the diagnostic relationship of recipient troponin and adverse outcomes following cardiac transplant. We included 27 studies with 1,684 cardiac transplant recipients. Patients with acute rejection had a statistically significant late elevation in standardised troponin measurements taken at least 1 month postoperatively (SMD 0.98, 95% CI 0.33–1.64). However, pooled diagnostic accuracy was poor (sensitivity 0.414, 95% CrI 0.174–0.696; specificity 0.785, 95% CrI 0.567–0.912; BAUC 0.607, 95% CrI 0.469–0.723). In summary, late troponin elevation in heart transplant recipients is associated with acute cellular rejection in adults, but its stand-alone diagnostic accuracy is poor. Further research is needed to assess its performance in predictive modelling of adverse outcomes following cardiac transplant.

Systematic Review Registration: identifier CRD42021227861

Perioperative gabapentinoid use lowers short-term opioid consumption following lower limb arthroplasty: Systematic review and meta-analysis

BACKGROUND

The management of post-operative pain and high levels of acute and chronic opioid use following total knee arthroplasty (TKA) and total hip arthroplasty (THA) remain challenges to the perioperative team. We performed a system-atic review and meta-analysis to determine the opioid sparing effects, analgesic effects, and safety profile of perioperative gabapentinoid usage in lower limb arthroplasty.

METHODS

We searched multiple databases from inception until May 2019 and included randomized controlled trials (RCT) on perioperative gabapentinoids in lower limb arthroplasty. The primary outcome was cumulative opioid con-sumption (oral morphine equivalents) at 24 and 48 hours, and the secondary outcomes were pain scores, time to hospi-tal discharge, and adverse events including nausea, vomiting, pruritus, and sedation. Methodological quality was as-sessed using the Cochrane tool. The grading of recommendations assessment, development, and evaluation method-ology for the certainty of evidence was also used.

RESULTS

We included 19 RCT involving 2,455 patients undergoing lower limb arthroplasty. The overall methodological quality of included studies was good. Gabapentinoid use was associated with a significant reduction in opioid consump-tion at 24 hour (mean difference (MD) 22.81 mg [95 percent Confidence Interval (CI) 13.64-31.98]) and 48 hour (MD 44.03 mg [95 percent CI 16.92-71.14]). We found no meaningful difference in pain scores at rest between gabapenti-noid and placebo groups at 24 or 48 hours. Gabapentinoid use reduced the risk of post-operative nausea (risk ratio (RR) 0.69 [95 percent CI 0.57-0.82]), vomiting (RR 0.65 [95 percent CI 0.47-0.91]), and pruritus (RR 0.60 [0.37-0.98]), but not sedation (RR 1.25 [0.76-2.06]). There was no effect on time to discharge from hospital (MD-0.05 days [95 per-cent CI -0.31 to 0.20].

CONCLUSIONS

The addition of gabapentinoids to perioperative multimodal analgesia decreases opioid consumption fol-lowing lower limb arthroplasty, while also lowering rates of nausea, vomiting, and pruritus. Further study is required to evaluate the effect of gabapentinoid use on long-term opioid use and dependence.

The prognostic significance of postoperative hyperbilirubinemia in cardiac surgery: systematic review and meta-analysis

Background

Hyperbilirubinemia following cardiac surgery is a common phenomenon and is of emerging interest in prognostic factor research. This systematic review and meta-analysis evaluated the association between post-operative hyperbilirubinemia (PH) and mortality and morbidity in cardiac surgery patients.

Methods

Ovid Medline and Ovid Embase were searched from inception to July 2020 for studies evaluating the prognostic significance of PH following cardiac surgery. Maximally adjusted odds ratios (OR) with associated confidence intervals were obtained from each study and pooled using random effects inverse variance modelling to assess in-hospital mortality. Standardised mean differences were pooled to assess Intensive Care Unit (ICU) and hospital length of stay (LOS). Qualitative analysis was performed to assess ventilation requirements and long-term mortality. Meta-regression was used to assess inter- and intra-study heterogeneity.

Results

3251 studies satisfied the selection criteria, from which 12 studies incorporating 3876 participants were included. PH significantly predicted in-hospital mortality with a pooled OR of 7.29 (95% CI 3.53, 15.09). Multiple pre-defined covariates contributed to the prognostic significance of PH, however only aortic cross-clamp time (p < 0.0001) and number of transfusions (p = 0.0001) were significant effect modifiers. PH significantly predicted both ICU LOS (Mean difference 1.32 [95% CI 0.04–2.6]) and hospital LOS (Mean difference 1.79 [95% CI 0.36–3.21]). Qualitative analysis suggested PH is associated with increased post-operative ventilation requirements and reduced long-term survival rates.

Conclusions

Hyperbilirubinemia is a cost-effective, widely available prognostic marker of adverse outcomes following cardiac surgery, albeit with residual sources of heterogeneity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13019-022-01870-2.

Association of perioperative cryoprecipitate transfusion and mortality after cardiac surgery

BACKGROUND

Cryoprecipitate is often transfused in patients undergoing cardiac surgery. However, its safety and effectiveness remains uncertain.

METHODS

We conducted a propensity-score matched analysis of data from the Australian and New Zealand Society of Cardiac and Thoracic Surgeons National Cardiac Surgery Database. We included adults undergoing cardiac surgery between 2005-2018 across 38 sites. We estimated the association between perioperative cryoprecipitate transfusion and clinical outcomes, with a primary outcome of operative mortality.

RESULTS

Of 119,132 eligible patients, 11,239 (9.43%) patients received cryoprecipitate. The median cumulative dose was 8 units (interquartile range, 5 to 10). After propensity-score matching, we matched 9,055 cryoprecipitate recipients to 9,055 controls. Postoperative cryoprecipitate transfusion was associated with reduced operative (Odds Ratio [OR], 0.82; 99% confidence interval [CI], 0.69 to 0.97; P=0.002) and long term (Hazard Ratio, 0.92; 99% CI, 0.87 to 0.97; P=0.0042) mortality. It was also associated with a reduction in acute kidney injury (OR, 0.85; 99% CI, 0.73 to 0.98; P=0.0037] and all-cause infection (OR, 0.77; 99% CI, 0.67 to 0.88; P<0.0001). These findings were observed despite increased rates of return to operating theatre (OR, 1.36; 99% CI, 1.22 to 1.51; P<0.0001) and cumulative 4-hour postoperative chest tube output (Adjusted Mean Difference in mL, 97.69; 99% CI, 81.65 to 113.74; P<0.0001).

CONCLUSIONS

In a large, multicentre cohort study and after propensity-score matching, perioperative transfusion of cryoprecipitate was associated with reduced operative and long-term mortality.

Cryoprecipitate Transfusion After Cardiac Surgery

OBJECTIVES

The association of cryoprecipitate transfusion with patient outcomes after cardiac surgery is unclear. We aimed to investigate the predictors of, and outcomes associated with, postoperative cryoprecipitate transfusion in cardiac surgery patients.

METHODS

We used the Medical Information Mart for Intensive Care III and IV databases. We included adults undergoing cardiac surgery, and propensity score matched cryoprecipitate-treated patients to controls. Using the matched cohort, we investigated the association of cryoprecipitate use with clinical outcomes. The primary outcome was in-hospital mortality. Secondary outcomes were infection, acute kidney injury, intensive care unit length of stay, hospital length of stay, and chest tube output at 2-hour intervals.

RESULTS

Of 12,043 eligible patients, 283 (2.35%) patients received cryoprecipitate. The median dose was 5.83 units (IQR 4.17-7.24) given at a median first transfusion time of 1.75 hours (IQR 0.73-4.46) after intensive care unit admission. After propensity scoring, we matched 195 cryoprecipitate recipients to 743 controls. Postoperative cryoprecipitate transfusion was not significantly associated with in-hospital mortality (odds ratio [OR] 1.10; 99% confidence interval [CI] 0.43-2.84; p=0.791), infection (OR 0.77; 99% CI 0.45-1.34; p=0.220), acute kidney injury (OR 1.03; 99% CI 0.65-1.62; p=0.876) or cumulative chest tube output (adjusted mean difference 8 hrs post transfusion, 11 mL; 99% CI -104 to 125; p=0.804).

CONCLUSIONS

Although cryoprecipitate was typically given to sicker patients with more bleeding, its administration was not associated with worse outcomes. Large, multicentred studies are warranted to further elucidate cryoprecipitate's safety profile and patterns of use in cardiac surgery.

Machine learning predicts the short-term requirement for invasive ventilation among Australian critically ill COVID-19 patients

OBJECTIVE(S)

To use machine learning (ML) to predict short-term requirements for invasive ventilation in patients with COVID-19 admitted to Australian intensive care units (ICUs).

DESIGN

A machine learning study within a national ICU COVID-19 registry in Australia.

PARTICIPANTS

Adult patients who were spontaneously breathing and admitted to participating ICUs with laboratory-confirmed COVID-19 from 20 February 2020 to 7 March 2021. Patients intubated on day one of their ICU admission were excluded.

MAIN OUTCOME MEASURES

Six machine learning models predicted the requirement for invasive ventilation by day three of ICU admission from variables recorded on the first calendar day of ICU admission; (1) random forest classifier (RF), (2) decision tree classifier (DT), (3) logistic regression (LR), (4) K neighbours classifier (KNN), (5) support vector machine (SVM), and (6) gradient boosted machine (GBM). Cross-validation was used to assess the area under the receiver operating characteristic curve (AUC), sensitivity, and specificity of machine learning models.

RESULTS

300 ICU admissions collected from 53 ICUs across Australia were included. The median [IQR] age of patients was 59 [50-69] years, 109 (36%) were female and 60 (20%) required invasive ventilation on day two or three. Random forest and Gradient boosted machine were the best performing algorithms, achieving mean (SD) AUCs of 0.69 (0.06) and 0.68 (0.07), and mean sensitivities of 77 (19%) and 81 (17%), respectively.

CONCLUSION

Machine learning can be used to predict subsequent ventilation in patients with COVID-19 who were spontaneously breathing and admitted to Australian ICUs.

Prognostic Significance of Elevated Troponin in Adult Heart Transplant Recipients: A Systematic Review and Meta-Analysis

OBJECTIVES

Cardiac troponin is a highly specific biomarker of myocardial injury that is of prognostic significance in a range of cardiovascular diseases. However, the prognostic value of elevated troponin in cardiac transplant recipients is uncertain. We aimed to evaluate the prognostic value of elevated cardiac troponin in predicting adverse recipient outcomes following heart transplant.

MATERIALS AND METHODS

We searched MEDLINE (Ovid), Embase (Ovid), and the Cochrane Library from inception until December 2020 and included studies reporting associations between elevated recipient troponin and outcomes after cardiac transplant. We generated summary odds ratios for associations with short- and long-term adverse events and used descriptive analyses where meta-analyses were inappropriate.

RESULTS

We included 15 studies involving 1830 patients undergoing cardiac transplant. The risk of primary graft failure was greater in recipients with elevated troponin than in those without (odds ratio = 3.09; 95% CI, 1.08-8.87). Considerable interstudy heterogeneity (I2 statistic 98%) was partially explained by variations in study design, troponin subtype, and overall risk of bias. Descriptive analyses suggested associations between elevated recipient troponin and long-term adverse cardiac events, coronary artery disease, and mortality.

CONCLUSIONS

Elevated cardiac troponin in cardiac transplant recipients may be prognostic for primary graft failure, adverse cardiac events, coronary artery disease, and mortality. Further high-quality, prospective, and multicenter research is needed to demonstrate the clinical applicability of these findings.

Sex Differences in Opioid Administration After Cardiac Surgery

OBJECTIVES

To assess whether there are sex-based differences in the administration of opioid analgesic drugs among inpatients after cardiac surgery.

DESIGN

A retrospective cohort study.

SETTING

At a tertiary academic referral center.

PARTICIPANTS

Adult patients who underwent cardiac surgery from 2014 to 2019.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was the cumulative oral morphine equivalent dose (OMED) for the postoperative admission. Secondary outcomes were the daily difference in OMED and the administration of nonopioid analgesics. The authors developed multivariate regression models controlling for known confounders, including weight and length of stay. A total of 3,822 patients (1,032 women and 2,790 men) were included. The mean cumulative OMED was 139 mg for women and 180 mg for men, and this difference remained significant after adjustment for confounders (adjusted mean difference [aMD], -33.21 mg; 95% CI, -47.05 to -19.36 mg; p < 0.001). The cumulative OMED was significantly lower in female patients on postoperative days 1 to 5, with the greatest disparity observed on day 5 (aMD, -89.83 mg; 95% CI, -155.9 to -23.80 mg; p = 0.009). By contrast, women were more likely to receive a gabapentinoid (odds ratio, 1.91; 95% CI, 1.42-2.58; p < 0.001). The authors found no association between patient sex and the administration of other nonopioid analgesics or specific types of opioid analgesics. The authors found no association between patient sex and pain scores recorded within the first 48 hours after extubation, or the number of opioids administered in close proximity to pain assessments.

CONCLUSIONS

Female sex was associated with significantly lower amounts of opioids administered after cardiac surgery.

Donor Cardiac Troponin for Prognosis of Adverse Outcomes in Cardiac Transplantation Recipients: a Systematic Review and Meta-analysis

BACKGROUND

Cardiac troponin is a highly specific and widely available marker of myocardial injury, and elevations in cardiac transplant donors may influence donor selection. We aimed to investigate whether elevated donor troponin has a role as a prognostic biomarker in cardiac transplantation.

METHODS

In a systematic review and meta-analysis, we searched MEDLINE, Embase, and the Cochrane Library, without language restriction, from inception to December 2020. We included studies reporting the association of elevated donor troponin with recipient outcome after cardiac transplant. We generated summary odds ratios and hazard ratios for the association of elevated donor troponin with short- and long-term adverse outcomes. Methodological quality was monitored using the Quality In Prognosis Studies tool, and interstudy heterogeneity was assessed using a series of sensitivity and subgroup analyses.

RESULTS

We included 17 studies involving 15 443 patients undergoing cardiac transplantation. Elevated donor troponin was associated with increased odds of graft rejection at 1 y (odds ratio, 2.54; 95% confidence interval, 1.22-5.28). No significant prognostic relationship was found between donor troponin and primary graft failure, short- to long-term mortality, cardiac allograft vasculopathy, and pediatric graft loss.

CONCLUSIONS

Elevated donor troponin is not associated with an increased short- or long-term mortality postcardiac transplant despite increasing the risk of graft rejection at 1 y. Accordingly, an elevated donor troponin in isolation should not exclude donation.