Genome-wide association studies with experimental validation identify a protective role for B lymphocytes against chronic post-surgical pain.

BACKGROUND: Chronic post-surgical pain (CPSP) significantly impacts patients' recovery and quality of life. Although environmental risk factors are well-established, genetic risk remains less understood. METHODS: A meta-analysis of genome-wide association studies followed by partitioned heritability was performed on 1350 individuals across five surgery types: hysterectomy, mastectomy, abdominal, hernia, and knee. In subsequent animal studies, withdrawal thresholds to evoked mechanical stimulation were measured in Rag1 null mutant and wild-type mice after plantar incision and laparotomy. Cell sorting by flow cytometry tracked recruitment of immune cell types. RESULTS: We discovered 77 genome-wide significant single-nucleotide polymorphism (SNP) hits, distributed among 24 loci and 244 genes. Meta-analysis of all cohorts estimated a SNP-based narrow-sense heritability for CPSP at ∼39%, indicating a substantial genetic contribution. Partitioned heritability analysis across a wide variety of tissues revealed enrichment of heritability in immune system-related genes, particularly those associated with B and T cells. Rag1 null mutant mice lacking both T and B cells exhibited exacerbated and prolonged allodynia up to 42 days after surgery, which was rescued by B-cell transfer. Recruitment patterns of B cells but not T cells differed significantly during the first 7 days after injury in the footpad, lymph nodes, and dorsal root ganglia. CONCLUSIONS: These findings suggest a key protective role for the adaptive immune system in the development of chronic post-surgical pain.

Differences and Similarities Among COVID-19 Patients Treated in Seven ICUs in Three Countries Within One Region: An Observational Cohort Study.

OBJECTIVES: To investigate healthcare system-driven variation in general characteristics, interventions, and outcomes in coronavirus disease 2019 (COVID-19) patients admitted to the ICU within one Western European region across three countries. DESIGN: Multicenter observational cohort study. SETTING: Seven ICUs in the Euregio Meuse-Rhine, one region across Belgium, The Netherlands, and Germany. PATIENTS: Consecutive COVID-19 patients supported in the ICU during the first pandemic wave. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Baseline demographic and clinical characteristics, laboratory values, and outcome data were retrieved after ethical approval and data-sharing agreements. Descriptive statistics were performed to investigate country-related practice variation. From March 2, 2020, to August 12, 2020, 551 patients were admitted. Mean age was 65.4 ± 11.2 years, and 29% were female. At admission, Acute Physiology and Chronic Health Evaluation II scores were 15.0 ± 5.5, 16.8 ± 5.5, and 15.8 ± 5.3 (p = 0.002), and Sequential Organ Failure Assessment scores were 4.4 ± 2.7, 7.4 ± 2.2, and 7.7 ± 3.2 (p < 0.001) in the Belgian, Dutch, and German parts of Euregio, respectively. The ICU mortality rate was 22%, 42%, and 44%, respectively (p < 0.001). Large differences were observed in the frequency of organ support, antimicrobial/inflammatory therapy application, and ICU capacity. Mixed-multivariable logistic regression analyses showed that differences in ICU mortality were independent of age, sex, disease severity, comorbidities, support strategies, therapies, and complications. CONCLUSIONS: COVID-19 patients admitted to ICUs within one region, the Euregio Meuse-Rhine, differed significantly in general characteristics, applied interventions, and outcomes despite presumed genetic and socioeconomic background, admission diagnosis, access to international literature, and data collection are similar. Variances in healthcare systems' organization, particularly ICU capacity and admission criteria, combined with a rapidly spreading pandemic might be important drivers for the observed differences. Heterogeneity between patient groups but also healthcare systems should be presumed to interfere with outcomes in coronavirus disease 2019.

Validation of the PreOperative Score to predict Post-Operative Mortality (POSPOM) in Dutch non-cardiac surgery patients.

BACKGROUND: Standardized risk assessment tools can be used to identify patients at higher risk for postoperative complications and death. In this study, we validate the PreOperative Score to predict Post-Operative Mortality (POSPOM) for in-hospital mortality in a large cohort of non-cardiac surgery patients. In addition, the performance of POSPOM to predict postoperative complications was studied. METHODS: Data from the control cohort of the TRACE (routine posTsuRgical Anesthesia visit to improve patient outComE) study was analysed. POSPOM scores for each patient were calculated post-hoc. Observed in-hospital mortality was compared with predicted mortality according to POSPOM. Discrimination was assessed by receiver operating characteristic curves with C-statistics for in-hospital mortality and postoperative complications. To describe the performance of POSPOM sensitivity, specificity, negative predictive values, and positive predictive values were calculated. For in-hospital mortality, calibration was assessed by a calibration plot. RESULTS: In 2490 patients, the observed in-hospital mortality was 0.5%, compared to 1.3% as predicted by POSPOM. 27.1% of patients had at least one postoperative complication of which 22.4% had a major complication. For in-hospital mortality, POSPOM showed strong discrimination with a C-statistic of 0.86 (95% CI, 0.78-0.93). For the prediction of complications, the discrimination was poor to fair depending on the severity of the complication. The calibration plot showed poor calibration of POSPOM with an overestimation of in-hospital mortality. CONCLUSION: Despite the strong discriminatory performance, POSPOM showed poor calibration with an overestimation of in-hospital mortality. Performance of POSPOM for the prediction of any postoperative complication was poor but improved according to severity.

Genetic polymorphisms and prediction of chronic post-surgical pain after hysterectomy-a subgroup analysis of a multicenter cohort study.

BACKGROUND: Chronic post-surgical pain (CPSP) is a serious problem. Clinical and psychological variables have not been able to explain all observed variance in prevalence and severity of CPSP. The first objective is to determine the association between genetic polymorphisms and the prevalence of CPSP after hysterectomy. The second objective is to analyze if the implementation of genetic polymorphisms into a previously performed clinical and psychological predictor analysis on the development of CPSP after hysterectomy will improve its discriminatory power. METHODS: A prospective multicenter cohort study was performed in patients undergoing hysterectomy for benign indication. Clinical and psychological variables were collected by questionnaires in the week before surgery, post-operatively up to day 4, 3 and 12 months after hysterectomy. Blood was collected and 16 polymorphisms previously suggested to be correlated to CPSP (COMT, GCH1, KCNS1, CACNG2, and OPRM1) were genotyped. Logistic regression analyses were performed. RESULTS: Three hundred and forty-five patients were available for the genetic analyses. The prevalence of CPSP 3 months post-operatively was 10.5% and after 12 months 7.9%. The polymorphism rs4818 within the COMT gene was associated with the prevalence of CPSP after 3 months. No polymorphisms were associated with CPSP after 12 months. The addition of rs4818 to the prediction model did not change its discriminatory power significantly. CONCLUSION: The rs4818 polymorphism within the COMT gene was associated with the prevalence of CPSP 3 months after hysterectomy, but the implementation of rs4818 into the prediction model did not significantly improve the chance of identifying hysterectomy patients at risk for CPSP.

Effect of Anesthesia on Microelectrode Recordings during Deep Brain Stimulation Surgery in Tourette Syndrome Patients.

BACKGROUND: Deep brain stimulation (DBS) is an accepted treatment for patients with medication-resistant Tourette syndrome (TS). Sedation is commonly required during electrode implantation to attenuate anxiety, pain, and severe tics. Anesthetic agents potentially impair the quality of microelectrode recordings (MER). Little is known about the effect of these anesthetics on MER in patients with TS. We describe our experience with different sedative regimens on MER and tic severity in patients with TS. METHODS: The clinical records of all TS patients who underwent DBS surgery between 2010 and 2018 were reviewed. Demographic data, stimulation targets, anesthetic agents, perioperative complications, and MER from each hemisphere were collected and analyzed. Single-unit activity was identified by filtering spiking activity from broadband MER data and principal component analysis with K-means clustering. Vocal and motor tics which caused artifacts in the MER data were manually selected using visual and auditory inspection. RESULTS: Six patients underwent bilateral DBS electrode implantation. In all patients, the target was the anterior internal globus pallidus. Patient comfort and hemodynamic and respiratory stability were maintained with conscious sedation with one or more of the following anesthetic drugs: propofol, midazolam, remifentanil, clonidine, and dexmedetomidine. Good quality MER and clinical testing were obtained in 9 hemispheres of 6 patients. In 3 patients, MER quality was poor on one side. CONCLUSION: Cautiously applied sedative drugs can provide patient comfort, hemodynamic and respiratory stability, and suppress severe tics, with minimal interference with MER.

Shifts of Transfusion Demand in Cardiac Surgery After Implementation of Rotational Thromboelastometry-Guided Transfusion Protocols: Analysis of the HEROES-CS (HEmostasis Registry of patiEntS in Cardiac Surgery) Observational, Prospective Open Cohort Database.

OBJECTIVES: Rotational thromboelastometry (ROTEM)-guided transfusion algorithms in cardiac surgery have been proven to be successful in reducing blood loss in randomized controlled trials. Using an institutional hemostasis registry of patients in cardiac surgery (HEROES-CS), the authors hypothesized that the use of ROTEM-guided transfusion algorithms would save blood products and overall costs in cardiac surgery in every day practice. DESIGN: Observational, prospective open cohort database. SETTING: Single-center academic hospital. PARTICIPANTS: Cardiac surgery patients. INTERVENTIONS: Implementation of ROTEM-guided bleeding management. MEASUREMENTS AND MAIN RESULTS: A classical-guided algorithm and a ROTEM-guided algorithm were used for patient blood management in 2 cohorts. Primary outcome was the use and amount of blood products and hemostatic medication. Secondary outcomes were amount of rethoracotomies, length of stay, and 30-day mortality. Finally, costs and savings were calculated. The classical-guided cohort comprised 204 patients, and ROTEM-guided cohort comprised 151 patients. Baseline characteristics showed excellent similarities after propensity score matching of 202 patients. Blood loss was lower after ROTEM guidance (p < 0.001). Absolute risk reduction was 17% for red blood cells (p = 0.024), 12% for fresh frozen plasma (p = 0.019), and 4% for thrombocyte concentrates (p = 0.582). More tranexamic acid was given, but not more fibrinogen concentrate, while desmopressin was given less often. Hospital length of stay was reduced by an overall median of 2 and a mean of 4 days (p < 0.001). Mortality and rethoracotomy rates were not affected. Potential savings were about €4,800 ($5,630) per patient. CONCLUSIONS: Implementation of a ROTEM-guided transfusion algorithm in cardiac surgery patients reduced the use of blood products and hemostatic medication, hereby saving costs. Reductions in mortality and rethoracotomy rates could not be found.

Metamizole vs. ibuprofen at home after day case surgery: A double-blind randomised controlled noninferiority trial.

BACKGROUND: NSAIDs and paracetamol are the cornerstones of pain treatment after day case surgery. However, NSAIDs have numerous contraindications and consequently are not suitable in up to 25% of patients. Metamizole is a non-opioid compound with a favourable gastro-intestinal and cardiovascular profile compared with NSAIDs. OBJECTIVES: The study aimed to assess if a combination of metamizole and paracetamol is noninferior to a combination of ibuprofen and paracetamol in treating pain at home after painful day case surgery. DESIGN: A double-blind randomised controlled trial. SETTING: Single centre. PATIENTS: Two hundred patients undergoing elective ambulatory haemorrhoid surgery, arthroscopic shoulder or knee surgery, or inguinal hernia repair. INTERVENTION: Patients were randomly allocated to receive either metamizole and paracetamol (n = 100) or ibuprofen and paracetamol (n = 100) orally for four days. MAIN OUTCOME MEASURES: Average postoperative pain intensity using a numerical rating scale and use of rescue medication were measured in the postanaesthesia care unit (PACU) and on postoperative days (POD) 1 to 3. A difference in mean numerical rating scale score of 1 point or less was considered noninferior. Adverse effects of study medication and satisfaction with study medication were measured on PODs 1 to 3 by telephone follow-up. RESULTS: In the PACU, the difference in mean ±â€ŠSD pain score between metamizole and paracetamol and ibuprofen and paracetamol was 0.85 ±â€Š0.78. From POD 1 to 3, this difference was lower than 1, resulting in noninferiority. Rescue opioid consumption in the PACU and on PODs 1 and 3 was not significantly different between treatment groups. Rescue opioid consumption on POD2 was significantly higher in the ibuprofen and paracetamol group (P = 0.042). Adverse effects of study medication and overall patient satisfaction were similar in both groups. CONCLUSION: Paracetamol/metamizole and paracetamol/ibuprofen are equally effective in treatment of acute postoperative pain at home after ambulatory surgery with comparable patient satisfaction levels. TRIAL REGISTRATION: European Union Clinical Trials Register 2015-003987-35.

Prevalence and Predictors of Patient Nonadherence to Pharmacological Acute Pain Therapy at Home After Day Surgery: A Prospective Cohort Study.

BACKGROUND: Good adherence to prescribed analgesics can be crucial to suppress or even prevent acute postoperative pain after day surgery. The aim of this study was to analyze prevalence and predictors of analgesic nonadherence after day surgery. METHODS: Elective patients scheduled for day surgery were prospectively enrolled from November 2008 to April 2010. Outcome parameters were measured by using questionnaire packages at 2 time points: 1 week preoperatively and 4 days postoperatively. The primary outcome parameter was analgesic nonadherence. Adherence was defined according to the patient's response to the questionnaire item "analgesia use as prescribed": full adherence, "yes"; partial adherence, "yes, sometimes"; nonadherence, "no." Bivariate and multivariate logistic regression analyses were performed to identify predictors of analgesic nonadherence. RESULTS: A total of 1,248 patients were included. The prevalence rates of analgesic nonadherence and partial adherence were 21.6% and 20.0%, respectively, in the total study population but dropped to 9.4% and 19.8%, respectively, in patients with moderate to severe pain. Low postoperative pain intensity and short duration of surgery were the most important predictors of analgesic nonadherence. The most important preoperative predictors for analgesic nonadherence were low preoperative pain intensity, low preoperative expectations of pain, and low fear of short-term effects of surgery. CONCLUSION: Analgesic nonadherence and partial adherence are common after day surgery but decrease as average pain intensity increases. Patients at risk for analgesic nonadherence can be identified during the preoperative period based on preoperative pain intensity, preoperative expectations of pain, and fear of surgery.

Use of Postoperative Peak Arterial Lactate Level to Predict Outcome After Cardiac Surgery.

OBJECTIVES: In the present study, the authors investigated the predictive value of postoperative peak arterial lactate levels for early and late mortality after cardiac surgery. DESIGN: Retrospective analysis of prospectively collected data. SETTING: Single-center study in an academic hospital. PARTICIPANTS: Adult patients who underwent cardiac surgery between 2004 and 2014 (n = 16,376). INTERVENTIONS: Different cardiac surgical procedures. MEASUREMENTS AND RESULTS: Patients were classified according to the peak arterial lactate level (PALL) within 3 days postoperatively. Logistic regression analysis and Cox regression analysis were performed to identify postoperative peak arterial lactate level as a predictor for early and late mortality respectively. In 8460 patients (51.7%), lactate was not measured postoperatively because these patients were managed according to the fast-track protocol. These patients constituted group 1 in our population but were excluded from the regression analysis. The remaining patients (n = 7,916; 48.3%) were divided according to the postoperative peak arterial lactate level (PALL): PALL<5 mmol/L (group 2), PALL 5 to 10 mmol/L (group 3), and PALL of>10 mmol/L (group 4). Early mortality was 3.7%, 20.4%, and 62.9% in groups 2, 3, and 4 respectively (p<0.0001). This mortality rate was significantly higher than that of group 1 (1.6%); p<0.0001. Multivariate regression analyses revealed postoperative peak arterial lactate as a significant predictor of 30-day mortality (odds ratio = 1.44 [1.39-1.48], p<0.001) as well as for late mortality (hazard ratio = 1.05 [1.01-1.10], p<0.025). CONCLUSIONS: Postoperative peak arterial lactate level in patients undergoing cardiac surgery is an independent predictor for both early and late mortality.

Accuracy, Precision, and Trending Ability of Uncalibrated Arterial Pressure Waveform Analysis of Cardiac Output in Patients With Impaired Left Ventricular Function: A Prospective, Observational Study.

OBJECTIVES: Uncalibrated arterial waveform analysis provides minimally invasive and continuous measurement of cardiac output (CO). This technique could be of great value in patients with impaired left ventricular function, but the validity in these patients is not well established. The aim of this study was to investigate the accuracy, precision, and trending ability of uncalibrated arterial waveform analysis of cardiac output in patients with impaired left ventricular function. DESIGN: Prospective, observational, method-comparison study. SETTING: Nonuniversity teaching hospital, single center. PARTICIPANTS: The study included 22 patients with a left ventricular ejection fraction of 40% or less undergoing elective coronary artery bypass grafting. INTERVENTIONS: In the period between induction of anesthesia and sternotomy, CO was measured using the FloTrac/Vigileo system (third-generation software) and intermittent pulmonary artery thermodilution before and after volume loading. MEASUREMENTS AND MAIN RESULTS: Accuracy and precision as determined using Bland-Altman analysis revealed a bias of -0.7 L/min, limits of agreement of -2.9 to 1.5 L/min, and a mean error of 55% for pooled data. Proportional bias and spread were present, indicating that bias and limits of agreement were underestimated for high CO values. Trending ability was assessed using 4-quadrant analysis, which revealed a concordance of 86%. Concordance from a clinical perspective was 36%. Polar plot analysis showed an angular bias of 13° degrees, with radial limits of agreement of -55° to 51°. Polar concordance at±30° was 50%. CONCLUSIONS: Arterial waveform analysis of cardiac output and pulmonary artery thermodilution cardiac output were not interchangeable in patients with impaired left ventricular function.

The patient with chronic heart failure undergoing surgery.

PURPOSE OF REVIEW: Congestive heart failure (CHF) is one of the most common diseases of the elderly patient. The underlying pathophysiology varies considerably and approximately 50% of the patients suffer from CHF with reduced left ventricular ejection fraction. Mortality in the perioperative period is increased in patients with CHF and this holds true for both minor and major surgeries. This review will summarize recent literature in the field of CHF and perioperative outcome in patients undergoing surgery with a special emphasis on actual guidelines, preoperative assessment and appropriate perioperative therapy. RECENT FINDINGS: In the past 18 months, new insights in the short and long-term effects of CHF in the perioperative period have been published. The role of left ventricular ejection fraction has been studied in noncardiac surgical patients and it has been demonstrated that an ejection fraction less than 30% is associated with a significant increase in mortality and myocardial infarctions. Moreover, in 25% of patients, acute exacerbation of heart failure takes place in the perioperative period. The European Society of Anesthesiology published new guidelines on the preoperative evaluation of patients with CHF. The role of adequate preoperative evaluation and preparation of patients with CHF is discussed widely. It becomes clear that parameters like brain natriuretic peptide play a crucial role in risk stratification and prediction of outcome. Also, the treatment of patients with low cardiac output was a topic, and it became clear that established therapies including the use of ß-mimetics and PDE-III inhibitors should only be initiated in very selected patient groups. However, adequately powered studies in patients with CHF are still missing and the majority of knowledge is based on patient undergoing cardiac surgery. SUMMARY: CHF is a source of considerable perioperative morbidity and mortality and in contrast to coronary artery disease, knowledge is very limited and additional research urgently needed.

Enhancement opportunities in operating room utilization; with a statistical appendix.

BACKGROUND: The purpose of this study was to assess the direct and indirect relationships between first-case tardiness (or "late start"), turnover time, underused operating room (OR) time, and raw utilization, as well as to determine which indicator had the most negative impact on OR utilization to identify improvement potential. Furthermore, we studied the indirect relationships of the three indicators of "nonoperative" time on OR utilization, to recognize possible "trickle down" effects during the day. MATERIALS AND METHODS: (Multiple) linear regression analysis and mediation effect analysis were applied to a data set from all eight University Medical Centers in the Netherlands. This data set consisted of 190,071 OR days (on which 623,871 surgical cases were performed). RESULTS: Underused OR time at the end of the day had the strongest influence on raw utilization, followed by late start and turnover time. The relationships between the three "nonoperative" time indicators were negligible. The impact of the partial indirect effects of "nonoperative" time indicators on raw utilization were statistically significant, but relatively small. The "trickle down" effect that late start can cause resulting in an increased delay as the day progresses, was not supported by our results. CONCLUSIONS: The study findings clearly suggest that OR utilization can be improved by focusing on the reduction of underused OR time at the end of the day. Improving the prediction of total procedure time, improving OR scheduling by, for example, altering the sequencing of operations, changing patient cancellation policies, and flexible staffing of ORs adjusted to patient needs, are means to reduce "nonoperative" time.

Monocyte hyporesponsiveness and Toll-like receptor expression profiles in coronary artery bypass grafting and its clinical implications for postoperative inflammatory response and pneumonia: An observational cohort study.

BACKGROUND: Cardiac surgery with cardiopulmonary bypass has a major impact on the congenital immune response, in which Toll-like receptors (TLRs) are the first line of defence. Decreased surface expression of TLRs and impaired monocyte responsiveness to TLR ligands occur following surgery. However, the clinical implications of this altered immune response are not clear. OBJECTIVES: To study cardiac surgery induced changes in perioperative TLR expression and monocyte responsiveness, and the association with postoperative inflammatory complications. DESIGN: A prospective cohort study. SETTING: Single university hospital, enrolment March to December 2007. PATIENTS: Eighty-four out of 92 patients who underwent coronary artery bypass grafting (CABG) were followed up until hospital discharge. MAIN OUTCOME MEASURES: We assessed in-vivo TLR-2 and TLR-4 expression and ex-vivo monocyte responsiveness to TLR-2 and TLR-4 ligands, measured by Pam3Cys and lipopolysaccharide (LPS)-induced interleukin (IL)-6 and IL-8, and tumour necrosis factor alpha (TNF-α) secretion until 24 h after surgery. Patients were followed to identify adverse inflammatory and infectious outcomes. RESULTS: Monocyte TLR expression decreased during CABG but returned to baseline after 24 h [linear mixed effects (LME) over time P < 0.0001]. Monocyte responsiveness changed significantly over time, with marked postoperative hyporesponsiveness (LME P < 0.0001). Decreased monocyte responsiveness to LPS was associated with monocyte TLR-4 expression (LME for IL-6 P = 0.04, IL-8 P = 0.002, TNF-α P = 0.05). Intraoperative decrease of monocyte TLR-2 expression was associated with postoperative systemic inflammatory response syndrome (SIRS) and pneumonia [odds ratio (OR) 2.06, 95% confidence interval (95% CI) 1.14 to 3.72], but the perioperative decrease of monocyte TLR-4 expression was not (OR 1.10, 95% CI 0.80 to 1.52). CONCLUSION: CABG surgery induced a decrease in in-vivo monocyte TLR expression and also in ex-vivo monocyte responsiveness, with which monocyte TLR-4 expression and monocyte LPS responsiveness seemed to be associated. Decreased TLR-2 expression was associated with the occurrence of SIRS and pneumonia, suggesting a role in the cause of postoperative inflammatory conditions. REGISTRATION: Clinicaltrials.gov identifier: NCT00356746.

Arterial pressure waveform analysis versus thermodilution cardiac output measurement during open abdominal aortic aneurysm repair: a prospective observational study.

BACKGROUND: Arterial pressure waveform analysis enables continuous, minimally invasive measurement of cardiac output. Haemodynamic instability compromises the reliability of the technique and a means of maintaining accurate measurement in this circumstance would be useful. OBJECTIVES: To investigate the accuracy, precision and trending ability of arterial pressure waveform cardiac output obtained with FloTrac/Vigileo, versus pulmonary artery thermodilution in patients undergoing elective open abdominal aortic aneurysm repair. DESIGN: A prospective observational study. SETTING: Operating room in a university hospital. PATIENTS: Twenty-two patients scheduled for elective, open abdominal aortic aneurysm repair. MAIN OUTCOME MEASURES: Bias, limits of agreement and mean error as determined with Bland-Altman analysis between arterial waveform and thermodilution cardiac output assessment at four time points: after induction of anaesthesia (t1); after aortic cross-clamping (t2); after clamp release (t3); and after skin closure (t4). Trending ability from t1 to t2, t2 to t3 and t3 to t4, determined with four-quadrant and polar plot methodology. Clinically acceptable boundaries were defined in advance. RESULTS: Bland-Altman analysis revealed a bias of 0.54 l min (thermodilution minus arterial waveform cardiac output) for pooled data, and 0.51 (t1), -0.42 (t2), 0.98 (t3) and 0.98 (t4) l min at the different time points. Limits of agreement (LOA) were [-3.0 to 4.0] (pooled), [-2.0 to 3.0] (t1), [-3.1 to 2.3] (t2), [-2.5 to 4.4] (t3) and [-1.7 to 3.7] (t4) l min, resulting in mean errors of 58% (pooled), 45% (t1), 53% (t2), 52% (t3) and 41% (t4). Four-quadrant concordance was 65%. Polar plot analysis resulted in an angular bias of -12°, with radial LOA of -60° to 36°. CONCLUSION: Bias between arterial waveform and thermodilution cardiac output was within a predefined acceptable range, but the mean error was above the accepted range of 30%. Trending ability was poor. Arterial waveform and thermodilution cardiac outputs are, therefore, not interchangeable in patients undergoing open abdominal aortic aneurysm repair.

Nonelective surgery at night and in-hospital mortality: Prospective observational data from the European Surgical Outcomes Study.

BACKGROUND: Evidence suggests that sleep deprivation associated with night-time working may adversely affect performance resulting in a reduction in the safety of surgery and anaesthesia. OBJECTIVE: Our primary objective was to evaluate an association between nonelective night-time surgery and in-hospital mortality. We hypothesised that urgent surgery performed during the night was associated with higher in-hospital mortality and also an increase in the duration of hospital stay and the number of admissions to critical care. DESIGN: A prospective cohort study. This is a secondary analysis of a large database related to perioperative care and outcome (European Surgical Outcome Study). SETTING: Four hundred and ninety-eight hospitals in 28 European countries. PATIENTS: Men and women older than 16 years who underwent nonelective, noncardiac surgery were included according to time of the procedure. INTERVENTION: None. MAIN OUTCOME MEASURES: Primary outcome was in-hospital mortality; the secondary outcome was the duration of hospital stay and critical care admission. RESULTS: Eleven thousand two hundred and ninety patients undergoing urgent surgery were included in the analysis with 636 in-hospital deaths (5.6%). Crude mortality odds ratios (ORs) increased sequentially from daytime [426 deaths (5.3%)] to evening [150 deaths (6.0%), OR 1.14; 95% confidence interval 0.94 to 1.38] to night-time [60 deaths (8.3%), OR 1.62; 95% confidence interval 1.22 to 2.14]. Following adjustment for confounding factors, surgery during the evening (OR 1.09; 95% confidence interval 0.91 to 1.31) and night (OR 1.20; 95% confidence interval 0.9 to 1.6) was not associated with an increased risk of postoperative death. Admittance rate to an ICU increased sequentially from daytime [891 (11.1%)], to evening [347 (13.8%)] to night time [149 (20.6%)]. CONCLUSION: In patients undergoing nonelective urgent noncardiac surgery, in-hospital mortality was associated with well known risk factors related to patients and surgery, but we did not identify any relationship with the time of day at which the procedure was performed. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT01203605.

The influence of anesthesia-controlled time on operating room scheduling in Dutch university medical centres.

BACKGROUND: Predicting total procedure time (TPT) entails several elements subject to variability, including the two main components: surgeon-controlled time (SCT) and anesthesia-controlled time (ACT). This study explores the effect of ACT on TPT as a proportion of TPT as opposed to a fixed number of minutes. The goal is to enhance the prediction of TPT and improve operating room scheduling. METHODS: Data from six university medical centres (UMCs) over seven consecutive years (2005-2011) were included, comprising 330,258 inpatient elective surgical cases. Based on the actual ACT and SCT, the revised prediction of TPT was determined as SCT × 1.33. Differences between actual and predicted total procedure times were calculated for the two methods of prediction. RESULTS: The predictability of TPT improved when the scheduling of procedures was based on predicting ACT as a proportion of SCT. CONCLUSIONS: Efficient operating room (OR) management demands the accurate prediction of the times needed for all components of care, including SCT and ACT, for each surgical procedure. Supported by an extensive dataset from six UMCs, we advise grossing up the SCT by 33% to account for ACT (revised prediction of TPT = SCT × 1.33), rather than employing a methodology for predicting ACT based on a fixed number of minutes. This recommendation will improve OR scheduling, which could result in reducing overutilized OR time and the number of case cancellations and could lead to more efficient use of limited OR resources.

Temporal changes of soluble ST2 after cardiovascular interventions.

BACKGROUND: Soluble ST2 (sST2), a member of the IL-1 receptor family, has been proposed as a novel biomarker with predictive value for heart failure and mortality in patients suffering from cardiovascular diseases. The influence of clinical characteristics on variability of sST2 levels is relatively unexplored. Here, we studied the effect of cardiovascular interventions and clinical characteristics on plasma sST2 expression levels. MATERIAL AND METHODS: In the current study, sST2 levels were assessed in the plasma of patients scheduled for coronary artery bypass grafting (CABG) (n = 76), percutaneous coronary intervention (PCI) (n = 68) or peripheral vascular surgery (n = 27). RESULTS: Age was the only classical risk factor significantly correlating with sST2 levels. Soluble ST2 levels were significantly increased 1 h after CABG (48 [33-70] vs. 61 [42-89] pg/mL, P = 0·001) and increased even further after 24 h (1116 [578-13 666] pg/mL, P < 0·001). An average threefold increase in sST2 levels was also observed in patients 24 h after peripheral interventions (30 [21-41] vs. 98 [48-211] pg/mL, P < 0·001). Two months after PCI, we found that sST2 levels were significantly higher compared with baseline levels (41 [29-61] vs. 48 [31-80] pg/mL, P = 0·007, n = 52). In addition, we did not observe an association between sST2 and any inflammatory or cardiac-specific markers that were measured in this study. CONCLUSIONS: Soluble ST2 increases significantly following cardiovascular interventions. The notion of a recent cardiovascular intervention is a strong determinant of sST2 levels and therefore needs to be taken into account when exploring sST2 as predictor of future cardiovascular events.