Abnormal Iron Status and Adverse Outcome After Elective Cardiac Surgery: A Prospective, Observational Multicenter Study.

OBJECTIVES: To investigate the incidence of preoperative abnormal iron status and its association with packed red blood cell (PRBC) transfusion, postoperative major complications, and new onset of clinically significant disability in patients undergoing elective cardiac surgery. DESIGN: A prospective, observational multicenter cohort study. SETTING: Three cardiac surgical centers in the Netherlands between 2019 and 2021. Recruitment was on hold between March and May 2020 due to COVID-19. PATIENTS: A total of 427 patients aged 60 years and older who underwent elective on-pump cardiac surgery. MEASUREMENTS AND MAIN RESULTS: The primary endpoint was a 30-day PRBC transfusion. Secondary endpoints were postoperative major complications within 30 days (eg, acute kidney injury, sepsis), and new onset of clinically significant disability within 120 days of surgery. Iron status was evaluated before surgery. Abnormal iron status was present in 45.2% of patients (n = 193), and most frequently the result of iron deficiency (27.4%, n = 117). An abnormal iron status was not associated with PRBC transfusion (adjusted relative risk [ARR] 1.2; 95% CI 0.9-1.8: p = 0.227) or new onset of clinically significant disability (ARR 2.0; 95% CI 0.9-4.6: p = 0.098). However, the risk of postoperative major complications was increased in patients with an abnormal iron status (ARR 1.7; 95% CI 1.1-2.5: p = 0.012). CONCLUSIONS: An abnormal iron status before elective cardiac surgery was associated with an increased risk of postoperative major complications but not with PRBC transfusion or a new onset of clinically significant disability.

Cardiac Surgery in Jehovah's Witnesses: 329 Consecutive Cases.

OBJECTIVES: This study aimed to describe the outcome of Jehovah's Witnesses (JWs) undergoing cardiac surgery at the authors' center. DESIGN: A single-center retrospective cohort study. SETTING: At a cardiovascular center with a tertiary intensive care unit (ICU) and specific experience with cardiac surgery in JWs. The institutional protocol describing all perioperative care in JWs has been applied for 21 years. PARTICIPANTS: All JWs undergoing cardiac surgery in the Amphia Hospital from January 1, 2001 to January 31, 2022. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The study cohort comprised 329 JWs undergoing cardiac surgery. Twenty-three patients (6.8%) were treated preoperatively for anemia. The mean European System for Cardiac Operative Risk Evaluation score was 5.1 (range 0-18). Coronary artery bypass grafting (53.2%) was performed most frequently, followed by aortic valve replacement (13.4%). Mean preoperative hemoglobin levels were 14.5 g/dL (range 9.8-18.5 g/dL), dropping to 11.6 g/dL (range 6.6-15.6 g/dL) at hospital discharge. Mean blood loss was 439 ± 349 mL in the first 12 hours postsurgery. Maximum mean postoperative troponin levels were 431 ± 424 ng/L. Resternotomy and postoperative myocardial infarction occurred in 3.6% and 4.2% of patients, respectively. On average, patients had an ICU stay of 1.4 ± 1.8 days and a hospital stay of 6.8 ± 4.2 days. Hospital mortality was 0.6% and was related to cardiac failure. CONCLUSIONS: This study demonstrated that cardiac surgery in JWs is safe when adhering to a strict perioperative patient blood management protocol.

Preoperative anaemia and outcome after elective cardiac surgery: a Dutch national registry analysis.

BACKGROUND: Previous studies have shown that preoperative anaemia in patients undergoing cardiac surgery is associated with adverse outcomes. However, most of these studies were retrospective, had a relatively small sample size, and were from a single centre. The aim of this study was to analyse the relationship between the severity of preoperative anaemia and short- and long-term mortality and morbidity in a large multicentre national cohort of patients undergoing cardiac surgery. METHODS: A nationwide, prospective, multicentre registry (Netherlands Heart Registration) of patients undergoing elective cardiac surgery between January 2013 and January 2019 was used for this observational study. Anaemia was defined according to the WHO criteria, and the main study endpoint was 120-day mortality. The association was investigated using multivariable logistic regression analysis. RESULTS: In total, 35 484 patients were studied, of whom 6802 (19.2%) were anaemic. Preoperative anaemia was associated with an increased risk of 120-day mortality (adjusted odds ratio [aOR] 1.7; 95% confidence interval [CI]: 1.4-1.9; P<0.001). The risk of 120-day mortality increased with anaemia severity (mild anaemia aOR 1.6; 95% CI: 1.3-1.9; P<0.001; and moderate-to-severe anaemia aOR 1.8; 95% CI: 1.4-2.4; P<0.001). Preoperative anaemia was associated with red blood cell transfusion and postoperative morbidity, the causes of which included renal failure, pneumonia, and myocardial infarction. CONCLUSIONS: Preoperative anaemia was associated with mortality and morbidity after cardiac surgery. The risk of adverse outcomes increased with anaemia severity. Preoperative anaemia is a potential target for treatment to improve postoperative outcomes.

Predictors for extubation failure in COVID-19 patients using a machine learning approach.

INTRODUCTION: Determining the optimal timing for extubation can be challenging in the intensive care. In this study, we aim to identify predictors for extubation failure in critically ill patients with COVID-19. METHODS: We used highly granular data from 3464 adult critically ill COVID patients in the multicenter Dutch Data Warehouse, including demographics, clinical observations, medications, fluid balance, laboratory values, vital signs, and data from life support devices. All intubated patients with at least one extubation attempt were eligible for analysis. Transferred patients, patients admitted for less than 24 h, and patients still admitted at the time of data extraction were excluded. Potential predictors were selected by a team of intensive care physicians. The primary and secondary outcomes were extubation without reintubation or death within the next 7 days and within 48 h, respectively. We trained and validated multiple machine learning algorithms using fivefold nested cross-validation. Predictor importance was estimated using Shapley additive explanations, while cutoff values for the relative probability of failed extubation were estimated through partial dependence plots. RESULTS: A total of 883 patients were included in the model derivation. The reintubation rate was 13.4% within 48 h and 18.9% at day 7, with a mortality rate of 0.6% and 1.0% respectively. The grandient-boost model performed best (area under the curve of 0.70) and was used to calculate predictor importance. Ventilatory characteristics and settings were the most important predictors. More specifically, a controlled mode duration longer than 4 days, a last fraction of inspired oxygen higher than 35%, a mean tidal volume per kg ideal body weight above 8 ml/kg in the day before extubation, and a shorter duration in assisted mode (< 2 days) compared to their median values. Additionally, a higher C-reactive protein and leukocyte count, a lower thrombocyte count, a lower Glasgow coma scale and a lower body mass index compared to their medians were associated with extubation failure. CONCLUSION: The most important predictors for extubation failure in critically ill COVID-19 patients include ventilatory settings, inflammatory parameters, neurological status, and body mass index. These predictors should therefore be routinely captured in electronic health records.

[Adenotonsillectomy with or without intubation? Safety of the adenotonsillectomy without endotracheal tube in children]. / Wel of geen intubatie bij adenotonsillectomie volgens Sluder?Resultaten.

OBJECTIVE: To determine the safety of the non-intubated and intubated adenotonsillectomy by the Sluder method in children DESIGN: Retrospective database study METHOD: We compared the data of adenotonsillectomy by the Sluder method in children until thirteen years of two teaching hospitals from 2014 until 2017. In the Amphia Hospital the procedure was performed without endotracheal tube placement and without perioperative opioids, in the Haga Hospital the patients were intubated and received perioperative opioids. Primary outcome was reoperation for postoperative haemorrhage. Secondary outcomes included desaturation (saturation ≤ 90% > 1 min), severe hypoxemia (saturation ≤ 85% for ≥ 5 min), airway complications, bradycardia, total postoperative haemorrhages, use of rescue medication, hospital readmission and 30-day mortality. RESULTS: A total of 1370 patients were analysed: 1267 adenotonsillectomies and 103 tonsillectomies. Median operation time was 7 minutes in the non-intubated group versus 12 minutes in the intubated group. The primary outcome occurred in thirteen patients in the group without intubation (2.2%) and eleven times in the group with intubation (1.4%). There was one case of severe hypoxemia in the group without intubation. Desaturation occurred mostly in the group without intubation (26.4%) for a short time (median 0 min, interquartile range 0-1). Bradycardia was seen more in the group with intubation (4.1% vs 2.2%). CONCLUSION: The incidence of postoperative haemorrhage and severe airway complications after adenotonsillectomy by the Sluder method with and without endotracheal tube placement in both groups was comparable.

Late histopathologic characteristics of critically ill COVID-19 patients: Different phenotypes without evidence of invasive aspergillosis, a case series.

PURPOSE: Pathological data of critical ill COVID-19 patients is essential in the search for optimal treatment options. MATERIAL AND METHODS: We performed postmortem needle core lung biopsies in seven patients with COVID-19 related ARDS. Clinical, radiological and microbiological characteristics are reported together with histopathological findings. MEASUREMENT AND MAIN RESULTS: Patients age ranged from 58 to 83 years, five males and two females were included. Time from hospital admission to death ranged from 12 to 36 days, with a mean of 20 ventilated days. ICU stay was complicated by pulmonary embolism in five patients and positive galactomannan on bronchoalveolar lavage fluid in six patients, suggesting COVID-19 associated pulmonary aspergillosis. Chest CT in all patients showed ground glass opacities, commonly progressing to nondependent consolidations. We observed four distinct histopathological patterns: acute fibrinous and organizing pneumonia, diffuse alveolar damage, fibrosis and, in four out of seven patients an organizing pneumonia. None of the biopsy specimens showed any signs of invasive aspergillosis. CONCLUSIONS: In this case series common late histopathology in critically ill COVID patients is not classic DAD but heterogeneous with predominant pattern of organizing pneumonia. Postmortem biopsy investigations in critically COVID-19 patients with probable COVID-19 associated pulmonary aspergillosis obtained no evidence for invasive aspergillosis.

A 0.6-protamine/heparin ratio in cardiac surgery is associated with decreased transfusion of blood products.

OBJECTIVES: In cardiac surgery, adequate heparinization is necessary to prevent thrombus formation in the cardiopulmonary bypass (CPB). To counteract the heparin effect after weaning from CPB, protamine is administered. The optimal protamine/heparin ratio is still unknown. METHODS: In this before-after study, we evaluated the effect of a 0.6/1-protamine/heparin ratio implementation as of May 2017 versus a 0.8/1-protamine/heparin ratio on the 12-h postoperative blood loss and the amount of blood and blood component transfusions (fresh frozen plasma, packed red blood cells, fibrinogen concentrate, platelet concentrate and prothrombin complex concentrate) after cardiac surgery. A total of 2051 patients who underwent cardiac surgery requiring CPB between May 2016 and May 2018 were included. RESULTS: In the 0.6/1-protamine/heparin ratio group, only 28.8% of the patients received blood component transfusion, compared to 37.9% of the patients in the 0.8/1-ratio group (P < 0.001). The median 12-h postoperative blood loss was 230 ml (interquartile range 140-320) in the 0.6/1-ratio group versus 260 ml (interquartile range 155-365) in the 0.8/1-ratio group (P < 0.001). CONCLUSIONS: A 0.6/1-protamine/heparin ratio after weaning from CPB is associated with a significantly reduced 12-h postoperative blood loss and blood components transfusion.

Maintaining endotracheal tube cuff pressure at 20 mmHg during anterior cervical spine surgery to prevent dysphagia: a double-blind randomized controlled trial.

PURPOSE: Anterior cervical spine surgery is associated with postoperative dysphagia, sore throat and dysphonia. It is unclear, whether this is caused by increased endotracheal tube (ETT) cuff pressure after retractor placement. This study aims to assess the effect of ETT cuff pressure adjustment on postoperative dysphagia, sore throat and dysphonia. METHODS: In this, single-centre, observer and patient-blinded randomized controlled trial patients treated with anterior cervical spine surgery were randomized to adjustment of the ETT cuff pressure to 20 mmHg after placement of the retractor versus no adjustment. Primary outcome was the incidence and severity of postoperative dysphagia. Secondary outcomes were sore throat and dysphonia. Outcomes were evaluated on day one and 2 months after the operation. RESULTS: Of 177 enrolled patients, 162 patients (92.5%) could be evaluated. The incidence of dysphagia was 75.9% on day one and 34.6% 2 months after surgery. Dysphagia in the intervention and control group was present in 77.8% versus 74.1% of patients on day one (odds ratio (OR) 1.2, 95% confidence interval (CI) (0.6-2.5)) and 28.4% versus 40.7% of patients after 2 months (OR 0.6, 95% CI 0.3-1.1), respectively. Severity of dysphagia, sore throat and dysphonia was similar in both groups. CONCLUSIONS: Anterior cervical spine surgery is accompanied by a high incidence of postoperative dysphagia, lasting until at least 2 months after surgery in over a third of our patients. Adjusting ETT cuff pressure to 20 mmHg after retractor placement, as compared to controls, did not lower the risk for both short- and long-term dysphagia. Netherlands National Trial Registry Number: NTR 3542. These slides can be retrieved under electronic supplementary material.

Impact of Intraoperative Hypotension During Cardiopulmonary Bypass on Acute Kidney Injury After Coronary Artery Bypass Grafting.

OBJECTIVE: The aim of this study was to investigate whether acute kidney injury (AKI) after coronary artery bypass grafting can be attributed to intraoperative hypotension during cardiopulmonary bypass (IOH-CPB). DESIGN: Retrospective analysis. SETTING: Tertiary-care hospital. PARTICIPANTS: Patients undergoing on-pump coronary artery bypass grafting from June 2011 to January 2014. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: IOH-CPB was defined as blood pressure below several absolute and relative mean arterial pressure (MAP) thresholds and as the area under the curve for absolute MAP thresholds. AKI was defined as an absolute increase in serum creatinine of≥26 µmol/L within 48 hours or an increase to 150% or more within 7 days of surgery. Poisson regression with robust standard errors both before and after adjustment for confounders was used. Of the 1,891 patients included, 386 (20%) developed AKI. In univariable analysis, all IOH-CPB thresholds defined as a MAP of 50 mmHg or less and as a decrease in MAP of 60% from baseline were associated with a 1.07-to-1.11 times increased risk of AKI per 10 minutes of IOH-CPB (p<0.01). After adjustment for potential confounders, IOH-CPB, irrespective of the definition chosen, was not associated with an increased risk of AKI. CONCLUSIONS: In the authors' study population, univariable analysis showed an association of IOH-CPB with AKI in patients undergoing isolated CABG, but this relationship disappeared after correction for well-known risk factors for AKI.

Postoperative Interleukin-6 Level and Early Detection of Complications After Elective Major Abdominal Surgery.

OBJECTIVE: To assess the association of systemic inflammation and outcome after major abdominal surgery. BACKGROUND: Major abdominal surgery carries a high postoperative morbidity and mortality rate. Studies suggest that inflammation is associated with unfavorable outcome. METHODS: Levels of C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-α and the systemic inflammatory response syndrome (SIRS) were assessed in 137 patients undergoing major abdominal surgery. Blood samples were drawn on days 0, 1, 3, and 7, and SIRS was scored during 48 hours after surgery. Primary outcome was a composite of mortality, pneumonia, sepsis, anastomotic dehiscence, wound infection, noncardiac respiratory failure, atrial fibrillation, congestive heart failure, myocardial infarction, and reoperation within 30 days of surgery. RESULTS: An IL-6 level more than 432 pg/mL on day 1 was associated with an increased risk of complications (adjusted odds ratio: 3.3; 95% confidence interval [CI]: 1.3-8.5) and a longer median length of hospital stay (7 vs 12 days, P < 0.001). As a single test, an IL-6 cut-off level of 432 pg/mL on day 1 yielded a specificity of 70% and a sensitivity of 64% for the prediction of complications (area under the curve: 0.67; 95% CI: 0.56-0.77). Levels of CRP started to discriminate from day 3 onward with a specificity of 87% and a sensitivity of 58% for a cut-off level of 203 mg/L (AUC: 0.73; 95% CI: 0.63-0.83). CONCLUSIONS: A high IL-6 level on day 1 is associated with postoperative complications. Levels of IL-6 help distinguish between patients at low and high risk for complications before changes in levels of CRP.

Maintaining endotracheal tube cuff pressure at 20 mm Hg to prevent dysphagia after anterior cervical spine surgery; protocol of a double-blind randomised controlled trial.

BACKGROUND: In anterior cervical spine surgery a retractor is obligatory to approach the spine. Previous studies showed an increase of endotracheal tube cuff pressure after placement of a retractor. It is known that high endotracheal tube cuff pressure increases the incidence of postoperative dysphagia, hoarseness, and sore throat. However, until now no evidence supports the fact whether adjusting the endotracheal tube cuff pressure during anterior cervical spine surgery will prevent this comorbidity. We present the design of a randomized controlled trial to determine whether adjusting endotracheal tube cuff pressure after placement of a retractor during anterior cervical spine surgery will prevent postoperative dysphagia. METHODS/DESIGN: 177 patients (aged 18-90 years) scheduled for anterior cervical spine surgery on 1 or more levels will be included. After intubation, endotracheal tube cuff pressure is manually inflated to 20 mm Hg in all patients. Patients will be randomized into two groups. In the control group endotracheal tube cuff pressure is not adjusted after retractor placement. In the intervention group endotracheal tube cuff pressure after retractor placement is maintained at 20 mm Hg and air is withdrawn when cuff pressure exceeds 20 mm Hg. Endotracheal tube cuff pressure is measured after intubation, before and after placement and removal of the retractor. Again air is inflated if cuff pressure sets below 20 mmHg after removal of the retractor. The primary outcome measure is postoperative dysphagia. Other outcome measures are postoperative hoarseness, postoperative sore throat, degree of dysphagia, length of hospital stay, and pneumonia. The study is a single centre double blind randomized trial in which patients and research nurses will be kept blinded for the allocated treatment during the follow-up period of 2 months. DISCUSSION: Postoperative dysphagia occurs frequently after anterior cervical spine surgery. This may be related to high endotracheal tube cuff pressure. Whether adaptation and maintaining the pressure after placement of the retractor will decrease the incidence of dysphagia, has to be determined by this trial. TRIAL REGISTRATION: Netherlands Trial Register (NTR) 3542: http://www.trialregister.nl.