Sex differences in pain catastrophizing and its relation to the transition from acute pain to chronic pain.

BACKGROUND AND IMPORTANCE: Differences exist between sexes in pain and pain-related outcomes, such as development of chronic pain. Previous studies suggested a higher risk for pain chronification in female patients. Furthermore, pain catastrophizing is an important risk factor for chronification of pain. However, it is unclear whether sex differences in catastrophic thinking could explain the sex differences in pain chronification. OBJECTIVES: The aim of this study was to examine sex differences in pain catastrophizing. Additionally, we investigated pain catastrophizing as a potential mediator of sex differences in the transition of acute to chronic pain. DESIGN, SETTINGS AND PARTICIPANTS: Adults visiting one of the 15 participating emergency departments in the Netherlands with acute pain-related complaints. Subjects had to meet inclusion criteria and complete questionnaires about their health and pain. OUTCOMES MEASURE AND ANALYSIS: The outcomes in this prospective cohort study were pain catastrophizing (short form pain catastrophizing) and pain chronification at 90 days (Numeric Rating Scale ≥ 1). Data was analysed using univariate and multivariable logistic regression models. Finally, stratified regression analyses were conducted to assess whether differences in pain catastrophizing accounted for observed differences in pain chronification between sexes. MAIN RESULTS: In total 1,906 patients were included. Females catastrophized pain significantly more than males (p < 0.001). Multiple regression analyses suggested that pain catastrophizing is associated with pain chronification in both sexes. CONCLUSIONS: This study reported differences between sexes in catastrophic cognitions in the development of chronic pain. This is possibly of clinical importance to identify high-risk patients and ensure an early intervention to prevent the transition from acute to chronic pain.

Effectiveness of tranexamic acid in burn patients undergoing surgery - a systematic review and meta-analysis.

BACKGROUND: Reducing blood loss during excisional surgery in burn patients remains a challenge. Tranexamic acid during surgery can potentially reduce blood loss. The use of tranexamic acid during excisional surgery in burn patients has recently been described in a review and meta-analysis. However, quality assessment on studies included was not performed and this review did not apply independent reviewers. Quality assessment of studies investigating the effectiveness of tranexamic acid in burn patients is crucial before concusions can be drawn. Therefore, we conducted a systematic review and meta-analysis of the literature investigating the effectiveness of tranexamic acid in burn patients undergoing surgery. METHODS: A systematic review and meta-analysis of the literature was conducted. The study was pre-registered in PROSPERO database (CRD42023396183). RESULTS: Five studies including two randomised controlled trials (RCTs) with a total of 303 patients were included. Risk of bias of the included studies was moderate to high. Individual results of the studies were heterogeneous. In three studies of moderate quality the administration of tranexamic acid resulted in a reduction of blood loss per unit excised area, accounting as moderate level of evidence. In two low-quality studies and one moderate quality study the administration of tranexamic acid resulted in a reduction of transfused packed Red Blood Cells (pRBC's), accounting for moderate level of evidence. Postoperative haemoglobin levels were higher after tranexamic acid administration in one study, accounting for insufficient evidence. Meta-analysis pooling overall blood loss from two separate RCTs failed to detect a statistically significant reduction. Substantial heterogeneity was observed. CONCLUSIONS: Moderate level of evidence indicates that tranexamic acid reduces blood loss per unit of excised area and transfusion of packed Red Blood Cells. Results indicate that tranexamic acid can be beneficial in burn patients undergoing surgery. More high-quality research is needed to confirm these results. Future studies should focus on the dosing of tranexamic acid, the administration approaches, and even consider combining these approaches. TRIAL REGISTRATION: PROSPERO: CRD42023396183.

Eligibility of cardiac arrest patients for extracorporeal cardiopulmonary resuscitation and their clinical characteristics: a retrospective two-centre study.

BACKGROUND AND IMPORTANCE: Sudden cardiac arrest has a high incidence and often leads to death. A treatment option that might improve the outcomes in refractory cardiac arrest is Extracorporeal Cardiopulmonary Resuscitation (ECPR). OBJECTIVES: This study investigates the number of in-hospital cardiac arrest (IHCA) and out-of-hospital cardiac arrest (OHCA) patients eligible to ECPR and identifies clinical characteristics that may help to identify which patients benefit the most from ECPR. DESIGN, SETTINGS AND PARTICIPANTS: A retrospective two-centre study was conducted in Rotterdam, the Netherlands. All IHCA and OHCA patients between 1 January 2017 and 1 January 2020 were screened for eligibility to ECPR. The primary outcome was the percentage of patients eligible to ECPR and patients treated with ECPR. The secondary outcome was the comparison of the clinical characteristics and outcomes of patients eligible to ECPR treated with conventional Cardiopulmonary Resuscitation (CCPR) vs. those of patients treated with ECPR. MAIN RESULTS: Out of 1246 included patients, 412 were IHCA patients and 834 were OHCA patients. Of the IHCA patients, 41 (10.0%) were eligible to ECPR, of whom 20 (48.8%) patients were actually treated with ECPR. Of the OHCA patients, 83 (9.6%) were eligible to ECPR, of whom 23 (27.7%) were actually treated with ECPR. In the group IHCA patients eligible to ECPR, no statistically significant difference in survival was found between patients treated with CCPR and patients treated with ECPR (hospital survival 19.0% vs. 15.0% respectively, 4.0% survival difference 95% confidence interval -21.3 to 28.7%). In the group OHCA patients eligible to ECPR, no statistically significant difference in-hospital survival was found between patients treated with CCPR and patients treated with ECPR (13.3% vs. 21.7% respectively, 8.4% survival difference 95% confidence interval -30.3 to 10.2%). CONCLUSION: This retrospective study shows that around 10% of cardiac arrest patients are eligible to ECPR. Less than half of these patients eligible to ECPR were actually treated with ECPR in both IHCA and OHCA.

A double-blind, randomised, placebo-controlled trial comparing intrathecal bupivacaine with bupivacaine plus morphine to reduce delirium in patients with hip fractures-Salmon-Mind trial study protocol.

Background: Surgical treatment of proximal femur fractures is complicated by postoperative delirium in about one-third of patients. Pain and opioid consumption are modifiable factors that may influence the incidence of delirium.1 An intrathecal injection of morphine may lead to a reduction in postoperative pain and reduced systemic opioid consumption. In current practice, the addition of morphine to intrathecal anaesthesia is commonly used but depends on the anaesthesiologist's preference. Recently, a retrospective study found that intrathecal morphine was independently associated with a lower incidence of delirium. However, this has to be confirmed in a prospective, randomised study. We hypothesise that using intrathecal morphine reduces postoperative pain and opioid consumption during the first 48 h after surgery and reduces the incidence of delirium during hospital admission. We also seek additional evidence of the association between neuronal injury (delirium) and neurofilament light in serum of patients with proximal femur fractures. Objective: The primary objective is to compare the incidence of delirium. The secondary objectives are to compare pain scores, systemic opioid consumption, and (opioid-related) side-effects. The tertiary objective is to test the association between intrathecal morphine and neurofilament light as a marker of neuronal injury. Study design: A double-blind, randomised, placebo-controlled intervention study is proposed. Study population: All patients with a proximal femur fracture who are scheduled for surgery under spinal anaesthesia. Intervention: The intervention is the addition of morphine 100 µg to the intrathecal injection for spinal anaesthesia. The intervention group will receive a mixture of bupivacaine 10 mg and morphine 100 µg. The control group will receive bupivacaine 10 mg. Clinical trial registration: EU Clinical Trials Register: EudraCT number 2020-002143-27.

Predicting blood loss in burn excisional surgery.

BACKGROUND: Blood loss during burn excisional surgery remains an important factor as it is associated with significant comorbidity, mortality and longer length of stay. Blood loss is, among others, influenced by length of surgery, burn size, excision size and age. Most literature available is aimed at large burns and little research is available for small burns. Therefore, the goal of this study is to investigate blood loss and develop a prediction model to identify patient at risk for blood loss during burn excisional surgery ≤ 10% body surface area. STUDY DESIGN AND METHODS: This retrospective study included adult patients who underwent burn excisional surgery of ≤ 10% body surface area in the period 2013-2018. Duplicates, patients with missing data and delayed surgeries were excluded. Primary outcome was blood loss. A prediction model for per-operative blood loss (>250 ml) was built using a multivariable logistic regression analysis with stepwise backward elimination. Discriminative ability was assessed by the area under the ROC-curve in conjunction with optimism and calibration. RESULTS: In total 269 patients were included for analysis. Median blood loss was 50 ml (0-150) / % body surface area (BSA) excised and 0.28 (0-0.81) ml / cm2. Median burn size was 4% BSA and median excision size was 2% BSA. Blood loss of> 250 ml was present in 39% of patients. The model can predict blood loss> 250 ml based on %BSA excised, length of surgery and ASA-score with an AUC of 0.922 (95% CI 0.883 - 0.949) and an AUC after optimism correction of 0.915. The calibration curve showed an intercept of 0.0 (95% CI -0.36 to 0.36) with a slope of 1.0 (95% CI 0.78-1.22). CONCLUSION: Median blood loss during burn excisional surgery of ≤ 10% BSA is 50 ml / % BSA excised and 0.28 ml / cm2 excised. However, a substantial part of patients is at risk for higher blood loss. The prediction model can predict P(blood loss>250 ml) with an AUC of 0.922, based on expected length of surgery, ASA-score and size of excision. The model can be used to identify patients at risk for significant blood loss (>250 ml).

Pain severity at emergency department discharge as a predictor for chronification of pain.

Introduction: Inadequate pain management remains a problem in the emergency department (ED) and might increase the risk of chronic pain. Previous studies suggested that pain intensity is associated with pain chronification in specific patient groups. This study aims to study the association between pain intensity {[verbal] numeric rating scale ([V]NRS) ≥ 7} at discharge from the ED and pain chronification in the general population. Objective: To assess whether a high pain score at discharge from the ED increases the risk of chronic pain development. Methods: Adults who visited the ED with pain as their main complaint, and who were not hospitalized, were eligible for inclusion. Chronic pain was defined as pain with an (V)NRS score ≥1 90 days after the ED visit and with a similar location to the acute pain. Results: We included 1906 patients, of whom 825 participants completed 90 days of follow-up. Approximately 34.1% left the ED with an (V)NRS score ≥7, and 67.8% reported an (V)NRS score of ≥1 90 at days. Of all patients leaving the ED with an (V)NRS score ≥7, 76.5% developed chronic pain vs 63.2% of patients with (V)NRS score <7 (P < 0.01). After correction, this difference was borderline statistically significant with an odds ratio of 1.45 (95% confidence interval: 0.99-2.13, P = 0.054). Various sensitivity analyses using a different (V)NRS at discharge and different definitions of chronic pain at 90 days showed a significant difference in the chronification of pain. Conclusion: This study suggests that pain intensity at discharge from the ED, regardless of the localization or cause of pain, increased the risk of developing chronic pain. By distinguishing patients at risk and providing an effective treatment, chronic pain and the associated burden of disease might be preventable.

The influence of anaesthetic choice on seizure duration of electroconvulsive therapy; etomidate versus methohexital.

BACKGROUND: Many of the anaesthetic drugs used for electroconvulsive therapy have anticonvulsant properties and may influence efficacy of electroconvulsive therapy. With this study we aim to provide more information on the effect of etomidate and methohexital on seizure duration. We explore the relationship between induction drug, motor and electroencephalography seizure duration. Moreover, we study the relationship of seizure duration and number of therapies. METHODS: In this retrospective study we collected data from patient records from 2005 until 2016. Inclusion criteria were the use of etomidate and/or methohexital and documentation of dosage, electroconvulsive therapy dosage and seizure duration. Exclusion criteria were missing data on either induction drug, dosage or seizure duration. RESULTS: Thirty seven patients were analysed. The mean age was 52 years and seventy six percent were female. Most patients were suffering from affective disorders (81%). Motor and electroencephalography seizure duration were analysed in 679 and 551 electroconvulsive therapies, respectively. Compared to methohexital, motor and electroencephalography seizures under etomidate were 7 and 13 s longer, respectively. Furthermore, there was a negative association between seizure duration and number of treatment and a negative association between seizure duration and electroconvulsive therapy dosage. CONCLUSIONS: This study demonstrates significant longer motor and electroencephalography seizure duration using etomidate compared to methohexital. Etomidate might therefore increase the effectiveness of electroconvulsive therapy. Moreover, we observed a negative association between seizure duration, number of treatment and electroconvulsive therapy dosage. With this study we contribute to the available literature comparing methohexital and etomidate as induction agents for electroconvulsive therapy.

Outcome in patients undergoing postponed elective surgery during the COVID-19 pandemic (TRACE II): study protocol for a multicentre prospective observational study.

INTRODUCTION: During the COVID-19 pandemic many non-acute elective surgeries were cancelled or postponed around the world. This has created an opportunity to study the effect of delayed surgery on health conditions prior to surgery and postsurgical outcomes in patients with postponed elective surgery. The control group of the Routine Postsurgical Anesthesia Visit to Improve Patient Outcome (TRACE I) study, conducted between 2016 and 2019, will serve as a control cohort. METHODS AND ANALYSIS: TRACE II is an observational, multicentre, prospective cohort study among surgical patients with postponed surgery due to COVID-19 in academic and non-academic hospitals in the Netherlands. We aim to include 2500 adult patients. The primary outcome will be the 30-day incidence of major postoperative complications. Secondary outcome measures include the 30-day incidence of minor postoperative complications, 1 year mortality, length of stay (in hospital, medium care and intensive care), quality of recovery 30 days after surgery and postoperative quality of life up to 1 year following surgery. Multivariable logistic mixed-effects regression analysis with a random intercept for hospital will be used to test group differences on the primary outcome. ETHICS AND DISSEMINATION: Ethical approval was obtained from the Institutional Review Board of Maastricht University Medical Centre+ and Amsterdam UMC. Findings will be presented at national and international conferences, as well as published in peer-reviewed scientific journals, with a preference for open access journals. Data will be made publicly available after publication of the main results. TRIAL REGISTRATION NUMBER: NL8841.

Adoption of a Postoperative Pain Self-Report Tool: Qualitative Study.

BACKGROUND: With electronic technologies, patients are provided with tools to easily acquire information and to manage and record their own health status. eHealth interventions are already broadly applied to perioperative care. In a similar way, we aimed to utilize a smartphone application to enable postoperative patients to partially self-manage their postoperative pain. The results of a previously performed proof-of-concept study regarding the application were promising, and nurses as well as patients were optimistic regarding this innovative mobile application. Nevertheless, in reality, it appears that the usage and overall implementation of this application have stagnated since its introduction. Problems with innovation adoption are not novel; various studies have been conducted to explore the reasons for low implementation success of eHealth applications and indicated that adoption is influenced by multiple organizational factors. This study investigated the influence of these organizational factors on the adoption process, aiming to provide more insight in the dos and don'ts for implementing eHealth in the working processes of hospital care. OBJECTIVE: This study aimed to provide insight in how to successfully implement a technological eHealth innovation in a general nonacademic hospital. METHODS: A qualitative study was conducted to explore organizational factors affecting the innovation adoption process. Data were collected by conducting semistructured one-on-one interviews with 11 stakeholders. The data were analyzed using thematic analysis identifying overarching themes. RESULTS: Absorptive capacity, referred to as an organization's dynamic capability pertaining to knowledge creation and utilization that enhances an organization's ability to gain and sustain a competitive advantage, was regarded as the most influential factor on the application's adoption. Accordingly, it appeared that innovation adoption is mainly determined by the capability and willingness to assimilate and transform new information into productive use and the ability to absorb a novel innovation. Absorptive capacity was found to be influenced by the innovation's benefit and the sense of ownership and responsibility. Organizational readiness and management support were also regarded as essential since absorptive capacity seemed to be mediated by these factors. The size of the hospital influenced eHealth adoption by the amount of resources available and by its organizational structure. CONCLUSIONS: In conclusion, absorptive capacity is essential for eHealth adoption, and it is mediated by management support and organizational readiness. It is recommended to increase the degree of willingness and ability to adopt an eHealth innovation by enhancing the relevance, engaging stakeholders, and assigning appropriate leaders to offer guidance.

Association between use of enhanced recovery after surgery protocols and postoperative complications in colorectal surgery in Europe: The EuroPOWER international observational study.

STUDY OBJECTIVE: Assess the relationship between the Enhanced Recovery After Surgery (ERAS®) pathway and routine care and 30-day postoperative outcomes. DESIGN: Prospective cohort study. SETTING: European centers (185 hospitals) across 21 countries. PATIENTS: A total of 2841 adult patients undergoing elective colorectal surgery. Each hospital had a 1-month recruitment period between October 2019 and September 2020. INTERVENTIONS: Routine perioperative care. MEASUREMENTS: Twenty-four components of the ERAS pathway were assessed in all patients regardless of whether they were treated in a formal ERAS pathway. A multivariable and multilevel logistic regression model was used to adjust for baseline risk factors, ERAS elements and country-based differences. RESULTS: A total of 1835 patients (65%) received perioperative care at a self-declared ERAS center, 474 (16.7%) developed moderate-to-severe postoperative complications, and 63 patients died (2.2%). There was no difference in the primary outcome between patients who were or were not treated in self-declared ERAS centers (17.1% vs. 16%; OR 1.00; 95%CI, 0.79-1.27; P = 0.986). Hospital stay was shorter among patients treated in self-declared ERAS centers (6 [5-9] vs. 8 [6-10] days; OR 0.82; 95%CI, 0.78-0.87; P < 0.001). Median adherence to 24 ERAS elements was 57% [48%-65%]. Adherence to ERAS-pathway quartiles (≥65% vs. <48%) suggested that patients with the highest adherence rates experienced a lower risk of moderate-to-severe complications (15.9% vs. 17.8%; OR 0.71; 95%CI, 0.53-0.96; P = 0.027), lower risk of death (0.3% vs. 2.9%; OR 0.10; 95%CI, 0.02-0.42; P = 0.002) and shorter hospital stay (6 [4-8] vs. 7 [5-10] days; OR 0.74; 95%CI, 0.69-0.79; P < 0.001). CONCLUSIONS: Treatment in a self-declared ERAS center does not improve outcome after colorectal surgery. Increased adherence to the ERAS pathway is associated with a significant reduction in overall postoperative complications, lower risk of moderate-to-severe complications, shorter length of hospital stay and lower 30-day mortality.

ED90 of spinal 2-chloroprocaine 1% in ambulatory knee arthroscopy up to 45 min: a randomized biased-coin- up-and-down sequential allocation trial.

BACKGROUND: A short acting spinal anesthetic facilitates smooth flow since quick recovery of motor function will facilitate unassisted ambulation. The aim of this study was to estimate the effective dose (ED90) of intrathecal 2-chloroprocaine 1% in outpatient knee arthroscopy. METHODS: Two cohorts were included in two different hospitals. In cohort I, a randomized biased-coin up-and-down design with 40 patients was used to find the ED90. Four dose-levels of plain 2-chloroprocaine 1% were used: 25, 30, 35 and 40 mg. The identified primary outcome, the ED90, was validated in 50 patients in cohort II with an open label design. Secondary outcomes included time to complete recovery from motor and sensory block with spinal injection as time zero, peak sensory block level, urine retention and time until hospital discharge. RESULTS: Forty patients were included in the final analysis in cohort I. The ED90 was estimated at 27.8 mg, successful spinal anesthesia was obtained in 38 patients (95%). Fifty patients were included in the final analysis in cohort II, 49 patients had successful anesthesia with a fixed round dose of 28 mg. In this Cohort, peak sensory block was T10/T11 (range: (L4-T4)). The median time to full recovery of the motor block was 60 min (45-60) and 90 min (75-105) for the sensory block. The mean time to hospital discharge was 2.9 hours (0.7). CONCLUSION: The ED90 of 2-chloroprocaine 1% in knee arthroscopy was estimated to be 27.8 mg. In an external population, the ED90 resulted in successful anesthesia in 98% of the patients (95% CI 89% to 100%). TRIAL REGISTRATION NUMBER: Netherlands Trial Registry (NL6769).

Blood transfusion decisions cannot be based on percutaneous haemoglobin measurements.

INTRODUCTION: Percutaneous measurement of haemoglobin (SpHb) has been an emerging technique in the past decades. It has been suggested that SpHb measurement could be used as a trend monitor and as a supportive tool for easier and faster transfusion decision-making. The aim of this study was to investigate whether SpHb monitoring is a useful instrument in transfusion decision-making. MATERIAL AND METHODS: Patients scheduled for surgery with expected blood loss over 800 mL were included in the study. SpHb was measured using a Masimo Rainbow probe. Blood samples were drawn before and after surgery and, if clinically indicated, during surgery. Moreover, perfusion parameters were analysed, as well as transfusion triggers. RESULTS: Based on transfusion triggers 27.1% of patients would not have been transfused according to National Guidelines (14.5% transfused in error, 12.5% not transfused when indicated). Invasive haemoglobin (invasive Hb) and SpHb were obtained 266 times in 75 patients. The mean invasive Hb was 7.37 ± 1.34 mmol L-1 and SpHb was 6.47 ± 0.81 mmol L-1 (P < 0.001). Bland-Altman analysis corrected for multiple measurements revealed proportional bias of -4.05 + 0.72 Hb (least bias at Hb 5.62). CONCLUSIONS: The precision of the SpHb measurement exceeded the acceptable range of error. We concluded that SpHb measurement using the Rainbow device is too unreliable to be an acceptable alternative to invasive Hb measurement, or even as a trend monitor or decision support tool.

Cell salvage in burn excisional surgery.

BACKGROUND: Hemostasis during burn surgery is difficult to achieve, and high blood loss commonly occurs. Bleeding control measures are limited, and many patients require allogeneic blood transfusions. Cell salvage is a well-known method used to reduce transfusions. However, its evidence in burns is limited. Therefore, this study aimed to examine the feasibility of cell salvage during burn surgery. STUDY DESIGN AND METHODS: A prospective, observational study was conducted with 16 patients (20 measurements) scheduled for major burn surgery. Blood was recovered by washing saturated gauze pads with heparinized saline, which was then processed using the Cell Saver. Erythrocyte concentrate quality was analyzed by measuring hemoglobin, hematocrit, potassium, and free hemoglobin concentration. Microbial contamination was assessed based on cultures at every step of the process. Differences in blood samples were tested using the Student's t-test. RESULTS: The red blood cell mass recovered was 29 ± 11% of the mass lost. Patients' preoperative hemoglobin and hematocrit levels were 10.5 ± 1.8 g/dL and 0.33 ± 0.05 L/L, respectively. The erythrocyte concentrate showed hemoglobin and hematocrit levels of 13.2 ± 3.9 g/dL and 0.40 ± 0.11 L/L thus showing a concentration effect. The potassium level was lower in the erythrocyte concentrate (2.5 ± 1.5 vs. 4.1 ± 0.4 mmol/L, p < 0.05). The free hemoglobin level was low (0.16 ± 0.21 µmol/L). All cultures of the erythrocyte concentrate showed bacterial growth compared to 21% of wound cultures. CONCLUSION: Recovering erythrocytes during burn excisional surgery using cell salvage is possible. Despite strict sterile handling, erythrocyte concentrates of all patients showed bacterial contamination. The consequence of this contamination remains unclear and should be investigated in future studies.

Cerebrospinal Fluid of Preeclamptic and Normotensive Pregnant Women Compared to Nonpregnant Women Analyzed with Mass Spectrometry.

Preeclampsia is a pregnancy-specific multiorgan disorder in which impaired placental functioning and excessive oxidative stress play an important role. We previously showed distinct differences between cerebrospinal fluid proteins in patients with preeclampsia and normotensive pregnant women. An additional group of nonpregnant women was included to study the presence of pregnancy-related proteins in normotensive and preeclamptic pregnancies and whether pregnancy-related proteins were associated with preeclampsia. Cerebrospinal fluid samples were tryptically digested and subsequently measured with a nano-LC-tribrid Orbitrap mass spectrometry system. Proteins were identified by shotgun proteomic analysis based on a data-dependent acquisition method. Proteins identified in preeclampsia, normotensive pregnant controls, and nonpregnant groups were compared to the Progenesis method according to the criteria as previously described and with a secondary analysis using a Scaffold method including Benjamini-Hochberg correction for multiple testing. For preeclampsia, the Progenesis and the Scaffold method together identified 15 (eight proteins for both analyses with one overlap) proteins that were significantly different compared to normotensive control pregnancies. Three of these 15 proteins, which were elevated in cerebrospinal fluid of preeclamptic women, were described to be pregnancy proteins with a calcium-binding function. Using two analysis methods (Progenesis and Scaffold), four out of 15 differential proteins were associated with pregnancy, as described in the literature. Three out of the four pregnancy-related proteins were elevated in preeclampsia. Furthermore, the contribution of elevated (n = 4/15) and downregulated (n = 2/15) calcium-binding proteins in preeclampsia is remarkably high (40%) and needs to be elucidated further.

Measurement of drug concentration and bacterial contamination after diluting morphine for intrathecal administration: an experimental study.

BACKGROUND: Low concentrations of morphine are required for safe dosing for intrathecal injections. Sometimes, manual dilution of morphine is performed to achieve these low concentrations, but risks dilution errors and bacterial contamination. The primary goal was to compare the concentrations of morphine and bupivacaine between four groups of syringes. The secondary goal was to investigate the difference in contamination rate between these groups. METHODS: Twenty-five experienced anesthesia providers were asked to prepare a mixture of bupivacaine 2.0 mg/ml and morphine 60 µg/ml using 3 different methods as clean and precise as possible. The fourth method used was the aspiration of ampoules prepared by the pharmacy. The concentrations of morphine and bupivacaine were measured by High-Pressure Liquid Chromatography (HPLC). The medication was cultured for bacterial contamination. RESULTS: Group 1 (median 60 µg/ml; 95% CI: 59-110 µg/ml) yielded 3 outliers above 180 µg/ml morphine concentration. Group 2 (76 µg/ml; 95% CI: 72-80 µg/ml) and 3 (69 µg/ml; 95% CI: 66-71 µg/ml) were consistently higher than the target concentration of 60 µg. The group "pharmacy" was precise and accurate (59 µg/ml; 95% CI: 59-59 µg/ml). Group 2 and "pharmacy" had one contaminated sample with a spore-forming aerobic gram-positive rod. CONCLUSION: Manually diluted morphine is at risk for deviating concentrations, which could lead to increased side-effects. Medication produced by the hospital pharmacy was highly accurate. Furthermore, even when precautions are undertaken, contamination of the medication is a serious risk and appeared to be unrelated to the dilution process.

Enhanced PeriOperative Care and Health protection programme for the prevention of surgical site infections after elective abdominal surgery (EPOCH): study protocol of a randomised controlled, multicentre, superiority trial.

INTRODUCTION: Surgical site infections (SSI) are a common postoperative complication. During the development of the new WHO guidelines on SSI prevention, also in the Netherlands was concluded that perioperative care could be optimised beyond the current standard practice. We selected a limited set of readily available, cheap and evidence-based interventions from these new guidelines that are not part of standard practice in the Netherlands and formulated an Enhanced PeriOperative Care and Health bundle (EPOCH). Here, we describe the protocol for an open-label, randomised controlled, parallel-group, superiority trial to test the effect of the EPOCH bundle added to (national) standard care in comparison to standard care alone on the incidence of SSI. METHODS AND ANALYSIS: EPOCH consists of intraoperative high fractional inspired oxygen (0.80); goal-directed fluid therapy; active preoperative, intraoperative and postoperative warming; perioperative glucose control and treatment of severe hyperglycaemia (>10 mmoll-1) and standardised surgical site handling. Patients scheduled for elective abdominal surgery with an incision larger than 5 cm are eligible for inclusion. Participants are randomised daily, 1:1 according to variable block sizes, and stratified per participating centre to either EPOCH added to standard care or standard care only. The primary endpoint will be SSI incidence according to the Centers for Disease Control and Prevention (CDC) definition within 30 days as part of routine clinical follow-up. Four additional questionnaires will be sent out over the course of 90 days to capture disability and costs. Other secondary endpoints include anastomotic leakage, incidence of incisional hernia, serious adverse events, hospital readmissions, length of stay and cost effectiveness. Analysis of the primary endpoint will be on an intention-to-treat basis. ETHICS AND DISSEMINATION: Ethics approval is granted by the Amsterdam UMC Medical Ethics Committee (reference 2015_121). Results will be disseminated through peer-reviewed journals and summaries shared with stakeholders. This protocol is published before analysis of the results. TRIAL REGISTRATION NUMBER: Registered in the Dutch Trial Register: NL5572.

The Modified A-DIVA Scale as a Predictive Tool for Prospective Identification of Adult Patients at Risk of a Difficult Intravenous Access: A Multicenter Validation Study.

Peripheral intravenous cannulation is the most common invasive hospital procedure but is associated with a high failure rate. This study aimed to improve the A-DIVA scale (Adult Difficult Intra Venous Access Scale) by external validation, to predict the likelihood of difficult intravenous access in adults. This multicenter study was carried out throughout five hospitals in the Netherlands. Adult participants were included, regardless of their indication for intravenous access, demographics, and medical history. The main outcome variable was defined as failed peripheral intravenous cannulation on the first attempt. A total of 3587 participants was included in this study. The first attempt success rate was 81%. Finally, five variables were included in the prediction model: a history of difficult intravenous cannulation, a difficult intravenous access as expected by the practitioner, the inability to detect a dilated vein by palpating and/or visualizing the extremity, and a diameter of the selected vein less than 3 millimeters. Based on a participant's individual score on the A-DIVA scale, they were classified into either a low, moderate, or high-risk group. A higher score on the A-DIVA scale indicates a higher risk of difficult intravenous access. The five-variable additive A-DIVA scale is a reliable and generalizable predictive scale to identify patients at risk of difficult intravenous access.

International multicenter observational study on assessment of ventilatory management during general anaesthesia for robotic surgery and its effects on postoperative pulmonary complication (AVATaR): study protocol and statistical analysis plan.

INTRODUCTION: Robotic-assisted surgery (RAS) has emerged as an alternative minimally invasive surgical option. Despite its growing applicability, the frequent need for pneumoperitoneum and Trendelenburg position could significantly affect respiratory mechanics during RAS. AVATaR is an international multicenter observational study aiming to assess the incidence of postoperative pulmonary complications (PPC), to characterise current practices of mechanical ventilation (MV) and to evaluate a possible association between ventilatory parameters and PPC in patients undergoing RAS. METHODS AND ANALYSIS: AVATaR is an observational study of surgical patients undergoing MV for general anaesthesia for RAS. The primary outcome is the incidence of PPC during the first five postoperative days. Secondary outcomes include practice of MV, effect of surgical positioning on MV, effect of MV on clinical outcome and intraoperative complications. ETHICS AND DISSEMINATION: This study was approved by the Institutional Review Board of the Hospital Israelita Albert Einstein. The study results will be published in peer-reviewed journals and disseminated at international conferences. TRIAL REGISTRATION NUMBER: NCT02989415; Pre-results.