Use of bitemporal NACA score documentation in prehospital emergency medical services- a retrospective study.

BACKGROUND: The assessment of illness severity in the prehospital setting is essential for guiding appropriate medical interventions. The National Advisory Committee for Aeronautics (NACA) score is a validated tool commonly used for this purpose. However, the potential benefits of using bitemporal documentation of NACA scores to capture the dynamic changes in emergency situations remain uncertain. The objective of this study was to evaluate the potential benefit of bitemporal NACA score documentation in the prehospital setting, specifically in assessing the dynamic changes of emergencies and facilitating quality improvement through enhanced documentation practices. METHODS: In this retrospective study, data from prehospital emergency patients were analyzed who received care from the physician response unit between January 1, 2018, and May 31, 2021. Patient demographics, NACA scores, indications for emergency care, and changes in NACA scores were extracted from medical records. Statistical analyses were performed to examine the associations between NACA scores, emergency categories, indications, and changes in NACA scores. RESULTS: The study included 4005 patients, predominantly categorized as NACA III (33.7% at initial assessment, 41.8% at subsequent assessment) and NACA IV (31.6% at initial assessment, 22.4% at subsequent assessment). There was a significant improvement in NACA scores during the provision of prehospital care (p < 0.01). Notably, prehospital emergencies attributed to internal medical, neurological, traumatic, and paediatric causes demonstrated significant improvements in NACA scores (p < 0.01). Gender-specific differences were also observed. CONCLUSION: Our study suggests that the bitemporal documentation of NACA scores can be advantageous in the prehospital setting and may have implications for research, practice, and policy.

Association of prehospital lactate levels with base excess in various emergencies - a retrospective study.

OBJECTIVES: Blood gas analysis, including parameters like lactate and base excess (BE), is crucial in emergency medicine but less commonly utilized prehospital. This study aims to elucidate the relationship between lactate and BE in various emergencies in a prehospital setting and their prognostic implications. METHODS: We conducted a retrospective analysis of prehospital emergency patients in Graz, Austria, from October 2015 to November 2020. Our primary aim was to assess the association between BE and lactate. This was assessed using Spearman's rank correlation and fitting a multiple linear regression model with lactate as the outcome, BE as the primary covariate of interest and age, sex, and medical emergency type as confounders. RESULTS: In our analysis population (n=312), lactate and BE levels were inversely correlated (Spearman's ρ, -0.75; p<0.001). From the adjusted multiple linear regression model (n=302), we estimated that a 1 mEq/L increase in BE levels was associated with an average change of -0.35 (95 % CI: -0.39, -0.30; p<0.001) mmol/L in lactate levels. Lactate levels were moderately useful for predicting mortality with notable variations across different emergency types. CONCLUSIONS: Our study highlights a significant inverse association between lactate levels and BE in the prehospital setting, underscoring their importance in early assessment and prognosis in emergency care. Additionally, the findings from our secondary aims emphasize the value of lactate in diagnosing acid-base disorders and predicting patient outcomes. Recognizing the nuances in lactate physiology is essential for effective prehospital care in various emergency scenarios.

Simplified Pain Management Including Fentanyl TTS in PACU Patients With Hip Fracture Surgery to Improve Patients' Well-Being: A Double-Blind Randomized Trial.

PURPOSE: Adequate pain management is eminently relevant for elderly and more vulnerable patients with hip fractures in the setting of pre and postoperative pain. This study compares postoperative hip fracture patients treated with standard pain management with a variety of medications or an approach with only one option in each medication category (nonopioid: acetaminophen; opioid: fentanyl TTS 12,5 mcg/hour; rescue medication: piritramide) to simplify the treatment algorithm for nurses and improve patient well-being. DESIGN: Double-blind randomized controlled trial. METHODS: The sample was cognitively intact patients (N = 141) with hip fractures in a tertiary university hospital. Administration of fentanyl 12 mcg/hour transdermal therapeutic system was administered by the nurses in the postanesthesia care unit (PACU) to address basal wound pain to improve patient well-being and patient treatment in the PACU for 24 hours to better control for early complications. FINDINGS: Well-being was equally increased in both groups in comparison to our preintervention data from 35.7% to over 60% and did not differ significantly between the intervention and control group. No statistically significant differences in numeric rating scale scores, rescue opioid dosage (piritramide i.v.) or in complications were present. CONCLUSIONS: This one-size-fits-all simplified pain management approach did not improve patient well-being or any other outcome but highlighted the importance of adequate pain management and a sufficient nurse-to-patient ratio.

Out-of-Hospital Arterial to End-Tidal Carbon Dioxide Gradient in Patients With Return of Spontaneous Circulation After Out-of-Hospital Cardiac Arrest: A Retrospective Study.

STUDY OBJECTIVE: End-tidal carbon dioxide (etCO2) is used to guide ventilation after achieving return of spontaneous circulation (ROSC) in certain out-of-hospital systems, despite an unknown difference between arterial and end-tidal CO2 (partial pressure of carbon dioxide [paCO2]-etCO2 difference) levels in this population. The primary aim of this study was to evaluate and quantify the paCO2-etCO2 difference in out-of-hospital patients with ROSC after nontraumatic cardiac arrest. METHODS: This retrospective single-center study included patients aged 18 years and older with sustained ROSC after nontraumatic out-of-hospital cardiac arrest. In patients with an existing out-of-hospital arterial blood gas analysis within 30 minutes after achieving ROSC, matching etCO2 values were evaluated. Linear regression and Bland-Altman plot analysis were performed to ascertain the primary endpoint of interest. RESULTS: We included data of 60 patients in the final analysis. The mean paCO2-etCO2 difference was 32 (±18) mmHg. Only a moderate correlation (R2=0.453) between paCO2 and etCO2 was found. Bland-Altman analysis showed a bias of 32 mmHg (95% confidence interval [CI], 27 to 36) [the upper limit of agreement of 67 mmHg (95% CI, 59 to 74) and the lower limit of agreement of -3 mmHg (95% CI, -11 to 5)]. CONCLUSION: The paCO2-etCO2 difference in patients with ROSC after out-of-hospital cardiac arrest is far from physiologic ranges, and the between-patient variability is high. Therefore, etCO2-guided adaption of ventilation might not provide adequate accuracy in this setting.

Idiopathic pseudoaneurysm of the popliteal artery with endovascular treatment: A case report.

Popliteal pseudoaneurysms are a rare vascular pathology, usually caused by trauma or iatrogenic interventions. Idiopathic cases are exceptionally uncommon. This case report aims to describe the diagnosis and successful endovascular treatment of an idiopathic pseudoaneurysm of the popliteal artery in a 90-year-old bedridden female patient presented with acute pain and swelling in the left knee at the emergency department. The patient underwent successful endovascular treatment with a covered stent and thrombin injection, leading to complete exclusion of the pseudoaneurysm. Popliteal pseudoaneurysms are a rare pathology, and idiopathic cases are even more uncommon. Endovascular therapy for popliteal pseudoaneurysms is associated with lower morbidity and mortality rates compared to open surgical repair. This case report highlights the importance of interdisciplinary collaboration between vascular surgeons and interventional radiologists in the management of rare vascular pathologies.

Using cardiovascular risk indices to predict mortality in Covid-19 patients with acute respiratory distress syndrome: a cross sectional study.

Covid-19 patients who require admission to an intensive care unit (ICU) have a higher risk of mortality. Several risk factors for severe Covid-19 infection have been identified, including cardiovascular risk factors. Therefore, the aim was to investigate the association between cardiovascular (CV) risk and major adverse cardiovascular events (MACE) and mortality of Covid-19 ARDS patients admitted to an ICU. A prospective cross-sectional study was conducted in a university hospital in Graz, Austria. Covid-19 patients who were admitted to an ICU with a paO2/fiO2 ratio < 300 were included in this study. Standard lipid profile was measured at ICU admission to determine CV risk. 31 patients with a mean age of 68 years were recruited, CV risk was stratified using Framingham-, Procam- and Charlson Comorbidity Index (CCI) score. A total of 10 (32.3%) patients died within 30 days, 8 patients (25.8%) suffered from MACE during ICU stay. CV risk represented by Framingham-, Procam- or CCI score was not associated with higher rates of MACE. Nevertheless, higher CV risk represented by Procam score was significantly associated with 30- day mortality (13.1 vs. 6.8, p = 0.034). These findings suggest that the Procam score might be useful to estimate the prognosis of Covid-19 ARDS patients.

Inverse association between apolipoprotein C-II and cardiovascular mortality: role of lipoprotein lipase activity modulation.

AIMS: Apolipoprotein C-II (ApoC-II) is thought to activate lipoprotein lipase (LPL) and is therefore a possible target for treating hypertriglyceridemia. Its relationship with cardiovascular risk has not been investigated in large-scale epidemiologic studies, particularly allowing for apolipoprotein C-III (ApoC-III), an LPL antagonist. Furthermore, the exact mechanism of ApoC-II-mediated LPL activation is unclear. METHODS AND RESULTS: ApoC-II was measured in 3141 LURIC participants of which 590 died from cardiovascular diseases during a median (inter-quartile range) follow-up of 9.9 (8.7-10.7) years. Apolipoprotein C-II-mediated activation of the glycosylphosphatidylinositol high-density lipoprotein binding protein 1 (GPIHBP1)-LPL complex was studied using enzymatic activity assays with fluorometric lipase and very low-density lipoprotein (VLDL) substrates. The mean ApoC-II concentration was 4.5 (2.4) mg/dL. The relationship of ApoC-II quintiles with cardiovascular mortality exhibited a trend toward an inverse J-shape, with the highest risk in the first (lowest) quintile and lowest risk in the middle quintile. Compared with the first quintile, all other quintiles were associated with decreased cardiovascular mortality after multivariate adjustments including ApoC-III as a covariate (all P < 0.05). In experiments using fluorometric substrate-based lipase assays, there was a bell-shaped relationship for the effect of ApoC-II on GPIHBP1-LPL activity when exogenous ApoC-II was added. In ApoC-II-containing VLDL substrate-based lipase assays, GPIHBP1-LPL enzymatic activity was almost completely blocked by a neutralizing anti-ApoC-II antibody. CONCLUSION: The present epidemiologic data suggest that increasing low circulating ApoC-II levels may reduce cardiovascular risk. This conclusion is supported by the observation that optimal ApoC-II concentrations are required for maximal GPIHBP1-LPL enzymatic activity.

Physician utilization in prehospital emergency medical services in Europe: an overview and comparison. / Visión general y comparación de la presencia de médicos en los servicios de emergencias médicas prehospitalarios en Europa.

OBJECTIVES: National and regional systems for emergency medical care provision may differ greatly. We sought to determine whether or not physicians are utilized in prehospital care and to what extent they are present in differentEuropean countries. MATERIAL AND METHODS: We collected information on 32 European countries by reviewing publications and sending questionnaires to authors of relevant articles as well as to officials of ministries of health (or equivalent), representatives of national societies in emergency medicine, or well-known experts in the specialty. RESULTS: Thirty of the 32 of European countries we studied (94%) employ physicians in prehospital emergency medical services. In 17 of the 32 (53%), general practitioners also participate in prehospital emergency care. Emergency system models were described as Franco-German in 27 countries (84%), as hybrid in 17 (53%), and as Anglo-American in 14 (44%). Multiple models were present simultaneously in 17 countries (53%). We were able to differentiate between national prehospital emergency systems with a novel classification based on tiers reflecting the degree of physician utilization in the countries. We also grouped the national systems by average population and area served. CONCLUSION: There are notable differences in system designs and intensity of physician utilization between different geographic areas, countries, and regions in Europe. Several archetypal models (Franco-German, hybrid, and Anglo- American) exist simultaneously across Europe.

OBJETIVO: Los sistemas nacionales y regionales de prestación de atención médica a las emergencias pueden diferir mucho entre sí. Se buscó dilucidar la presencia de médicos en la atención prehospitalaria y su implantación en los diferentes países europeos. METODO: Se analizaron los datos de 32 países europeos recogidos mediante la revisión de artículos publicados y a través de cuestionarios enviados a los autores de artículos científicos pertinentes, funcionarios del ministerio de sanidad (o equivalente), representantes de sociedades nacionales de medicina de urgencias o expertos reconocidos en medicina de urgencias. RESULTADOS: Treinta de los 32 países europeos investigados (94%) disponen de médicos en los servicios de emergencias prehospitalarios. En 17 de 32 (53%), los médicos generalistas también participan en la atención a las emergencias prehospitalarias. Los modelos de los sistemas de emergencias médicas (SEM) se describieron como francoalemanes en 27 países (84%), híbridos en 17 (53%) o angloamericanos en 14 (44%). En 17 países (53%), coexistían diferentes modelos. Utilizando una nueva forma de clasificación por niveles, basada en la población media y el área atendida por el SEM prehospitalario, se pudieron diferenciar claramente los diferentes modelos existentes. CONCLUSIONES: Se observan notables diferencias en los diseños de los SEM y en la presencia de los médicos entre las diferentes áreas geográficas, países y regiones de Europa. Coexisten varios modelos (francoalemán, híbrido y angloamericano), algunos simultáneamente, en los diferentes países.

Visión general y comparación de la presencia de médicos en los servicios de emergencias médicas prehospitalarios en Europa / Physician utilization in prehospital emergency medical services in Europe: an overview and comparison

Antecedentes: Los sistemas nacionales y regionales de prestación de atención médica a las emergencias pueden diferir mucho entre sí. Se buscó dilucidar la presencia de médicos en la atención prehospitalaria y su implantación en los diferentes países europeos. Métodos: Se analizaron los datos de 32 países europeos recogidos mediante la revisión de artículos publicados y a través de cuestionarios enviados a los autores de artículos científicos pertinentes, funcionarios del ministerio de sanidad (o equivalente), representantes de sociedades nacionales de medicina de urgencias o expertos reconocidos en medicina de urgencias. Resultados: Treinta de los 32 países europeos investigados (94%) disponen de médicos en los servicios de emergencias prehospitalarios. En 17 de 32 (53%), los médicos generalistas también participan en la atención a las emergencias prehospitalarias. Los modelos de los sistemas de emergencias médicas (SEM) se describieron como francoalemanes en 27 países (84%), híbridos en 17 (53%) o angloamericanos en 14 (44%). En 17 países (53%), coexistían diferentes modelos. Utilizando una nueva forma de clasificación por niveles, basada en la población media y el área atendida por el SEM prehospitalario, se pudieron diferenciar claramente los diferentes modelos existentes. Conclusiones: Se observan notables diferencias en los diseños de los SEM y en la presencia de los médicos entre las diferentes áreas geográficas, países y regiones de Europa. Coexisten varios modelos (francoalemán, híbrido y angloamericano), algunos simultáneamente, en los diferentes países. (AU)

Background: National and regional systems for emergency medical care provision may differ greatly. We sought to determine whether or not physicians are utilized in prehospital care and to what extent they are present in different European countries. Methods: We collected information on 32 European countries by reviewing publications and sending questionnairesto authors of relevant articles as well as to officials of ministries of health (or equivalent), representatives of national societies in emergency medicine, or well-known experts in the specialty. Results: Thirty of the 32 of European countries we studied (94%) employ physicians in prehospital emergency medical services. In 17 of the 32 (53%), general practitioners also participate in prehospital emergency care. Emergency system models were described as Franco-German in 27 countries (84%), as hybrid in 17 (53%), and as Anglo-American in 14(44%). Multiple models were present simultaneously in 17 countries (53%). We were able to differentiate between national prehospital emergency systems with a novel classification based on tiers reflecting the degree of physician utilization in the countries. We also grouped the national systems by average population and area served. Conclusions: There are notable differences in system designs and intensity of physician utilization between different geographic areas, countries, and regions in Europe. Several archetypal models (Franco-German, hybrid, and AngloAmerican) exist simultaneously across Europe. (AU)

Association of immediate versus delayed extubation of patients admitted to intensive care units postoperatively and outcomes: A retrospective study.

AIM OF THIS STUDY: This study seeks to investigate, whether extubation of tracheally intubated patients admitted to intensive care units (ICU) postoperatively either immediately at the day of admission (day 1) or delayed at the first postoperative day (day 2) is associated with differences in outcomes. MATERIALS AND METHODS: We performed a retrospective analysis of data from an Austrian ICU registry. Adult patients admitted between January 1st, 2012 and December 31st, 2019 following elective and emergency surgery, who were intubated at the day 1 and were extubated at day 1 or day 2, were included. We performed logistic regression analyses for in-hospital mortality and over-sedation or agitation following extubation. RESULTS: 52 982 patients constituted the main study population. 1 231 (3.3%) patients extubated at day 1 and 958 (5.9%) at day 2 died in hospital, 464 (1.3%) patients extubated at day 1 and 613 (3.8%) at day 2 demonstrated agitation or over-sedation after extubation during ICU stay; OR (95% CI) for in-hospital mortality were OR 1.17 (1.01-1.35, p = 0.031) and OR 2.15 (1.75-2.65, p<0.001) for agitation or over-sedation. CONCLUSIONS: We conclude that immediate extubation as soon as deemed feasible by clinicians is associated with favourable outcomes and may thus be considered preferable in tracheally intubated patients admitted to ICU postoperatively.

Assessing the weak links - Necessity and impact of regional cardiac arrest awareness campaigns for laypersons.

Introduction: Public knowledge of out-of-hospital cardiac arrest (OHCA), and initiation of basic life support (BLS) is crucial to increase survival in OHCA. Methods: The study analysed the knowledge and willingness to perform BLS of laypersons passing an AED at a public train station. Interviewees were recruited at two time points before and after a four year-long structured regional awareness campaign, which focused on call, compress, shock in a mid-size European city (270,000 inhabitants). Complete BLS was defined as multiple responses for call for help; initiation of chest compressions; and usage of an AED, without mentioning recovery position. Minimal BLS was defined as call for help and initiation of chest compressions. Results: A total of 784 persons were interviewed, 257 at baseline and 527 post-campaign. Confronted with a fictional OHCA, at baseline 8.5% of the interviewees spontaneously mentioned actions for complete BLS and 17.9% post-campaign (p = 0.009). An even larger increase in knowledge was seen in minimal BLS (34.6% vs 60.6%, p < 0.001). Conclusion: After a regional cardiac arrest awareness campaign, we found an increase in knowledge of BLS actions in the lay public. However, our investigation revealed severe gaps in BLS knowledge, possibly resulting in weak first links of the chain of survival.

Incidence and Outcomes of Cardiopulmonary Resuscitation in ICUs: Retrospective Cohort Analysis.

OBJECTIVES: We aim to describe incidence and outcomes of cardiopulmonary resuscitation (CPR) efforts and their outcomes in ICUs and their changes over time. DESIGN: Retrospective cohort analysis. SETTING: Patient data documented in the Austrian Center for Documentation and Quality Assurance in Intensive Care database. PATIENTS: Adult patients (age ≥ 18 yr) admitted to Austrian ICUs between 2005 and 2019. INTERVENTIONS: None. MEASUREMENTS ANDN MAIN RESULTS: Information on CPR was deduced from the Therapeutic Intervention Scoring System. End points were overall occurrence rate of CPR in the ICU and CPR for unexpected cardiac arrest after the first day of ICU stay as well as survival to discharge from the ICU and the hospital. Incidence and outcomes of ICU-CPR were compared between 2005 and 2009, 2010 and 2014, and 2015 and 2019 using chi-square test. A total of 525,518 first admissions and readmissions to ICU of 494,555 individual patients were included; of these, 72,585 patients (14.7%) died in hospital. ICU-CPR was performed in 20,668 (3.9%) admissions at least once; first events occurred on the first day of ICU admission in 15,266 cases (73.9%). ICU-CPR was first performed later during ICU stay in 5,402 admissions (1.0%). The incidence of ICU-CPR decreased slightly from 4.4% between 2005 and 2009, 3.9% between 2010 and 2014, and 3.7% between 2015 and 2019 ( p < 0.001). A total of 7,078 (34.5%) of 20,499 patients who received ICU-CPR survived until hospital discharge. Survival rates varied slightly over the observation period; 59,164 (12.0%) of all patients died during hospital stay without ever receiving CPR in the ICU. CONCLUSIONS: The incidence of ICU-CPR is approximately 40 in 1,000 admissions overall and approximately 10 in 1,000 admissions after the day of ICU admission. Short-term survival is approximately four out of 10 patients who receive ICU-CPR.

Comparison of Two Nuclear Magnetic Resonance Spectroscopy Methods for the Measurement of Lipoprotein Particle Concentrations.

Background: Measuring lipoprotein particle concentrations may help to improve cardiovascular risk stratification. Both the lipofit (Numares) and lipoprofile (LabCorp) NMR methods are widely used for the quantification of lipoprotein particle concentrations. Objective: The aim of the present work was to perform a method comparison between the lipofit and lipoprofile NMR methods. In addition, there was the objective to compare lipofit and lipoprofile measurements of standard lipids with clinical chemistry-based results. Methods: Total, LDL, and HDL cholesterol and triglycerides were measured with ß-quantification in serum samples from 150 individuals. NMR measurements of standard lipids and lipoprotein particle concentrations were performed by Numares and LabCorp. Results: For both NMR methods, differences of mean concentrations compared to ß-quantification-derived measurements were ≤5.5% for all standard lipids. There was a strong correlation between ß-quantification- and NMR-derived measurements of total and LDL cholesterol and triglycerides (all r > 0.93). For both, the lipofit (r = 0.81) and lipoprofile (r = 0.84) methods, correlation coefficients were lower for HDL cholesterol. There was a reasonable correlation between LDL and HDL lipoprotein particle concentrations measured with both NMR methods (both r > 0.9). However, mean concentrations of major and subclass lipoprotein particle concentrations were not as strong. Conclusions: The present analysis suggests that reliable measurement of standard lipids is possible with these two NMR methods. Harmonization efforts would be needed for better comparability of particle concentration data.

The LDL Apolipoprotein B-to-LDL Cholesterol Ratio: Association with Cardiovascular Mortality and a Biomarker of Small, Dense LDLs.

Background and Objective: Small, dense low-density lipoproteins (LDLs) are considered more atherogenic than normal size LDLs. However, the measurement of small, dense LDLs requires sophisticated laboratory methods, such as ultracentrifugation, gradient gel electrophoresis, or nuclear magnetic resonance. We aimed to analyze whether the LDL apolipoprotein B (LDLapoB)-to-LDL cholesterol (LDLC) ratio is associated with cardiovascular mortality and whether this ratio represents a biomarker for small, dense LDLs. Methods: LDLC and LDLapoB were measured (beta-quantification) and calculated (according to Friedewald and Baca, respectively) for 3291 participants of the LURIC Study, with a median (inter-quartile range) follow-up for cardiovascular mortality of 9.9 (8.7−10.7) years. An independent replication cohort included 1660 participants. Associations of the LDLapoB/LDLC ratio with LDL subclass particle concentrations (ultracentrifugation) were tested for 282 participants. Results: In the LURIC Study, the mean (standard deviation) LDLC and LDLapoB concentrations were 117 (34) and 85 (22) mg/dL, respectively; 621 cardiovascular deaths occurred. Elevated LDLapoB/LDLC (calculated and measured) ratios were significantly and independently associated with increased cardiovascular mortality in the entire cohort (fourth vs. first quartile: hazard ratio (95% confidence interval) = 2.07 (1.53−2.79)) and in statin-naïve patients. The association between calculated LDLapoB/LDLC ratio and cardiovascular mortality was replicated in an independent cohort. High LDLapoB/LDLC ratios were associated with higher LDL5 and LDL6 concentrations (both p < 0.001), but not with concentrations of larger LDLs. Conclusions: Elevated measured and calculated LDLapoB/LDLC ratios are associated with increased cardiovascular mortality. Use of LDLapoB/LDLC ratios allows estimation of the atherogenic risk conferred by small, dense LDLs.

Evaluation of the usefulness of non-invasive serum haemoglobin measurement in a perioperative setting in a prospective observational study.

Patient Blood Management (PBM) programmes seek to reduce the number of missed anaemic patients in the run-up to surgery. The aim of this study was to evaluate the usefulness of haemoglobin (Hb) measured non-invasively (SpHb) in preoperative screening for anaemia. We conducted a prospective observational study in a preoperative clinic. Adult patients undergoing examination for surgery who had their Hb measured by laboratory means also had their Hb measured non-invasively by a trained health care provider. 1216 patients were recruited. A total of 109 (9.3%) patients (53 men and 56 women) was found to be anaemic by standard laboratory Hb measurement. Sensitivity for SpHb to detect anaemic patients was 0.50 (95% CI 0.37-0.63) in women and 0.30 (95% CI 0.18-0.43) in men. Specificity was 0.97 (95% CI 0.95-0.98) in men and 0.93 (95% CI 0.84-1.0) in women. The rate of correctly classified patients was 84.7% for men and 89.4% for women. Positive predictive value for SpHb was 0.50 (95% CI 0.35-0.65) in men and 0.40 (95% CI 0.31-0.50) in women; negative predictive value was 0.93 (95% CI 0.92-0.94) in men and 0.95 (95% CI 0.94-0.96) in women. We conclude that due to low sensitivity, SpHb is poorly suitable for detecting preoperative anaemia in both sexes under standard of care conditions.

Combined femoral and popliteal nerve block is superior to local periarticular infiltration anaesthesia for postoperative pain control after total knee arthroplasty.

INTRODUCTION: After primary total knee arthroplasty (TKA), local periarticular infiltration anaesthesia (LIA) is a fast and safe method for postoperative pain control. Moreover, ultrasound-guided regional anaesthesia (USRA) with femoral and popliteal block is a standard procedure in perioperative care. Two analgesic regimens for TKA-LIA versus URSA with dexmedetomidine-were compared as an additive to ropivacaine. We hypothesised that the use of URSA provides a superior opioid sparing effect for TKA compared with LIA. METHODS: Fifty patients (planned 188 participants; safety analysis was performed after examining the first 50 participants) were randomised. These patients received LIA into the knee capsule during surgery with 60 ml of ropivacaine 0.5% and 1 ml of dexmedetomidine (100 µg ml-1) or two single-shot URSA blocks (femoral and popliteal block) before surgery with 15 ml of ropivacaine 0.5% and 0.5 ml of dexmedetomidine for each block. Postoperative opioid consumption in the first 48 h, pain assessment and complications were analysed. RESULTS: In the safety analysis, there was a significantly higher need for opioids in the LIA group, with a median oral morphine equivalent of 42.0 [interquartile range (IQR) 23.5-57.0] mg versus 27.0 [IQR 0.0-33.5] mg (P = 0.022). Due to this finding, the study was terminated for ethical considerations according to the protocol. CONCLUSION: This is the first study presenting data on LIA application in combination with dexmedetomidine. A superior opioid-sparing effect of URSA was observed when compared with LIA in TKA when dexmedetomidine is added to local anaesthetics. Also, a longer lasting opioid-sparing effect in the LIA group was observed when compared with the recently published literature; this difference could be attributed to the addition of dexmedetomidine. Therefore, multimodal analgesia regimens could be further improved when LIA or USRA techniques are combined with dexmedetomidine.