Pre-operative evaluation of adults undergoing elective noncardiac surgery: Updated guideline from the European Society of Anaesthesiology

The purpose of this update of the European Society of Anaesthesiology (ESA) guidelines on the pre-operative evaluation of the adult undergoing noncardiac surgery is to present recommendations based on the available relevant clinical evidence. Well performed randomised studies on the topic are limited and therefore many recommendations rely to a large extent on expert opinion and may need to be adapted specifically to the healthcare systems of individual countries. This article aims to provide an overview of current knowledge on the subject with an assessment of the quality of the evidence in order to allow anaesthesiologists all over Europe to integrate - wherever possible - this knowledge into daily patient care. The Guidelines Committee of the ESA formed a task force comprising members of the previous task force, members of ESA scientific subcommittees and an open call for volunteers was made to all individual active members of the ESA and national societies. Electronic databases were searched from July 2010 (end of the literature search of the previous ESA guidelines on pre-operative evaluation) to May 2016 without language restrictions. A total of 34 066 abtracts were screened from which 2536 were included for further analysis. Relevant systematic reviews with meta-analyses, randomised controlled trials, cohort studies, case-control studies and cross-sectional surveys were selected. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used to assess the level of evidence and to grade recommendations. The final draft guideline was posted on the ESA website for 4 weeks and the link was sent to all ESA members, individual or national (thus including most European national anaesthesia societies). Comments were collated and the guidelines amended as appropriate. When the final draft was complete, the Guidelines Committee and ESA Board ratified the guidelines.(AU)

The surgical safety checklist and patient outcomes after surgery: a prospective observational cohort study, systematic review and meta-analysis.

BACKGROUND: The surgical safety checklist is widely used to improve the quality of perioperative care. However, clinicians continue to debate the clinical effectiveness of this tool. METHODS: Prospective analysis of data from the International Surgical Outcomes Study (ISOS), an international observational study of elective in-patient surgery, accompanied by a systematic review and meta-analysis of published literature. The exposure was surgical safety checklist use. The primary outcome was in-hospital mortality and the secondary outcome was postoperative complications. In the ISOS cohort, a multivariable multi-level generalized linear model was used to test associations. To further contextualise these findings, we included the results from the ISOS cohort in a meta-analysis. Results are reported as odds ratios (OR) with 95% confidence intervals. RESULTS: We included 44 814 patients from 497 hospitals in 27 countries in the ISOS analysis. There were 40 245 (89.8%) patients exposed to the checklist, whilst 7508 (16.8%) sustained ≥1 postoperative complications and 207 (0.5%) died before hospital discharge. Checklist exposure was associated with reduced mortality [odds ratio (OR) 0.49 (0.32-0.77); P<0.01], but no difference in complication rates [OR 1.02 (0.88-1.19); P=0.75]. In a systematic review, we screened 3732 records and identified 11 eligible studies of 453 292 patients including the ISOS cohort. Checklist exposure was associated with both reduced postoperative mortality [OR 0.75 (0.62-0.92); P<0.01; I2=87%] and reduced complication rates [OR 0.73 (0.61-0.88); P<0.01; I2=89%). CONCLUSIONS: Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine.

Validation of the Swedish version of Quality of Recovery score -15: a multicentre, cohort study.

BACKGROUND: Quality of recovery (QoR) after surgery is often focused on morbidity, mortality and physiological changes, while well-being and emotional state are other important aspects that are often ignored. QoR is poorly investigated in clinical settings and a psychometrically tested questionnaire, QoR-15, has recently been developed. QoR-15 has not been validated for Swedish conditions. The aim of this study was to translate, adapt and validate QoR-15 to Swedish conditions (QoR-15swe). METHODS: A translation and cultural adaption was performed resulting in a Swedish version of the instrument, QoR-15swe. Patients answered the QoR-15swe before surgery, 24 and 48 h after surgery. Feasibility, validity, reliability and responsiveness of the QoR-15swe were evaluated. RESULTS: The QoR-15swe was feasible in 85.5% of the eligible patients. Construct validity was good, with significant correlations between QoR-15swe score and, ASA-PS class, grade of surgery, length of surgery and time in the post-anaesthesia care unit. The instrument demonstrated good internal consistency with an inter-item Cronbach's α of 0.83-0.87, and inter-dimension Cronbach's α was acceptable 0.71-0.76. Test-retest repeatability was also good with Cronbach's alpha > 0.99 and an interclass correlation coefficient of 0.992 (CI: 0.981-0.997). There were no floor and ceiling effects. Responsiveness assessed by Cliff's effect size was -0.23 indicating a moderate ability to detect change at 24 h postoperatively. CONCLUSION: We have translated and culturally adapted the QoR-15 into Swedish. The score demonstrated acceptable validity, reliability and responsiveness. The QoR-15swe is a clinically acceptable and feasible outcome measure after surgery in a Swedish population.

Shock treatment in a cohort of Scandinavian intensive care units in 2014.

BACKGROUND: Shock is common in intensive care units, and treatment includes fluids, vasopressor and/or inotropic drugs, guided by hemodynamic monitoring. The aim of this study was to identify current practice for treatment of shock in Scandinavian intensive care units. METHODS: Seven-day inception cohort study in 43 intensive care units in Scandinavia. Patients ≥ 15 years old receiving more than 4 h of cardiovascular acting drug infusion were included. The use of fluids, vasopressor and inotropic drugs, type of monitoring, and target values were recorded. RESULTS: One hundred and seventy-one patients were included. At inclusion, 136/168 (81%) had received vasopressor and/or inotropic drug therapy for less than 24 h, and 143/171 (84%) had received volume loading before the onset of vasoactive drug treatment. Ringer's solution was given to 129/143 (90%) of patients and starches in 3/143 (2%) patients. Noradrenaline was the most commonly used cardiovascular acting drug, given in 168/171 (98%) of cases while dopamine was rarely used. Mean arterial pressure was considered the most important variable for hemodynamic monitoring. Invasive arterial blood pressure was monitored in 166/171 (97%) of patients, arterial pulse wave analysis in 11/171 (7%), and echocardiography in 50/171 (29%). CONCLUSION: In this survey, Ringer's solution and noradrenaline were the most common first-line treatments in shock. The use of starches and dopamine were rare. Almost all patients were monitored with invasive arterial blood pressure, but comprehensive hemodynamic monitoring was used only in a minority of patients.

A comprehensive ovine model of blood transfusion.

BACKGROUND: The growing awareness of transfusion-associated morbidity and mortality necessitates investigations into the underlying mechanisms. Small animals have been the dominant transfusion model but have associated limitations. This study aimed to develop a comprehensive large animal (ovine) model of transfusion encompassing: blood collection, processing and storage, compatibility testing right through to post-transfusion outcomes. MATERIALS AND METHODS: Two units of blood were collected from each of 12 adult male Merino sheep and processed into 24 ovine-packed red blood cell (PRBC) units. Baseline haematological parameters of ovine blood and PRBC cells were analysed. Biochemical changes in ovine PRBCs were characterized during the 42-day storage period. Immunological compatibility of the blood was confirmed with sera from potential recipient sheep, using a saline and albumin agglutination cross-match. Following confirmation of compatibility, each recipient sheep (n = 12) was transfused with two units of ovine PRBC. RESULTS: Procedures for collecting, processing, cross-matching and transfusing ovine blood were established. Although ovine red blood cells are smaller and higher in number, their mean cell haemoglobin concentration is similar to human red blood cells. Ovine PRBC showed improved storage properties in saline-adenine-glucose-mannitol (SAG-M) compared with previous human PRBC studies. Seventy-six compatibility tests were performed and 17·1% were incompatible. Only cross-match compatible ovine PRBC were transfused and no adverse reactions were observed. CONCLUSION: These findings demonstrate the utility of the ovine model for future blood transfusion studies and highlight the importance of compatibility testing in animal models involving homologous transfusions.

Stored blood transfusion induces transient pulmonary arterial hypertension without impairing coagulation in an ovine model of nontraumatic haemorrhage.

BACKGROUND AND OBJECTIVES: Transfusion of blood products in particular older products is associated with patient morbidity. Previously, we demonstrated a higher incidence of acute lung injury in lipopolysaccharide-treated sheep transfused with stored blood products. As transfusion following haemorrhage is more common, we aimed to determine whether a 'first hit' of isolated haemorrhage would precipitate similar detrimental effects following transfusion and also disrupt haemostasis. MATERIALS AND METHODS: Anaesthetized sheep had 33% of their total blood volume collected into Leukotrap bags (Pall Medical), which were processed into packed red blood cells and cross-matched for transfusion into other sheep. After 30 mins, the sheep were resuscitated with either: fresh (<5 days old) or stored (35-42 days old) ovine blood followed by 4% albumin to replacement volume, albumin alone or normal saline alone and monitored for 4 h. RESULTS: The first hit of haemorrhage precipitated substantial decreases in mean arterial pressure however haemostasis was preserved. Transfusion of stored ovine blood induced (1) transient pulmonary arterial hypertension but no oedema and (2) reduced fibrinogen levels more than fresh blood, but neither induced coagulopathy. Thus, transfusion of stored blood affected pulmonary function even in the absence of overt organ injury. CONCLUSION: The fact that stored blood transfusions: (1) did not induce acute lung injury in contrast to previous lipopolysaccharide-primed animal models identifies the 'first hit' as an important determinant of the severity of transfusion-mediated injury; (2) impaired pulmonary dynamics verifies the sensitivity and vulnerability of the pulmonary system to injury.

Decreases in myocardial glucose and increases in pyruvate but not ischaemia are observed during porcine endotoxaemia.

BACKGROUND: Myocardial dysfunction occurs commonly in septic shock. It is not known whether this is due to local ischaemia and metabolic disturbances. Our hypothesis was that endotoxaemic myocardial dysfunction may be associated with interstitial ischaemic and metabolic changes, measured using interstitial microdialysis (MD). METHODS: Eighteen pigs were randomized to control (n=6) or endotoxin infusion (n=12). MD catheters were inserted into the myocardium for measurement of interstitial glucose, pyruvate and lactate concentrations. Plasma glucose and lactate concentrations and systemic haemodynamic parameters were measured simultaneously. RESULTS: Compared with the control group, the endotoxaemic animals had significantly decreased left ventricular stroke work and venous oxygen saturation (SvO2), and increased mean pulmonary artery pressure and plasma lactate. In the endotoxaemic group, decreases in interstitial glucose were observed, occurring simultaneously with increases in interstitial pruvate. Interstitial lactate: pyruvate ratios decreased with time in all animals. CONCLUSIONS: Despite severe systemic and pulmonary haemodynamic changes, interstitial MD measurements revealed no evidence of anaerobic metabolism in the myocardium of endotoxaemic pigs. There were, however, changes in glucose and pyruvate concentrations, suggesting local energy metabolic disturbances.

Exotic snake bite: a challenge for the Scandinavian anesthesiologist?

BACKGROUND: Venomous snake bites are uncommon in the Scandinavian countries. Envenomation from exotic snakes do however occur, mostly amongst snake handlers. This case report documents the effects and treatment for envenomation from Hoplocephalus bungaroides, or the Broad-Headed snake, native to eastern and southern Australia. Snakes of the genus Hoplocephalus have previously been described as of 'lesser medical importance' because of their rarity. METHODS: This case report describes the signs, symptoms and management of systemic envenomation in a previously healthy man. RESULTS: The patient developed signs of severe coagulopathy less than an hour after envenomation. There was also biochemical evidence of rhabdomyolysis, and cardiotoxicity. At no time did the patient develop respiratory insufficiency, neurotoxicity or renal failure. The patient was initially managed with i.v. crystalloids, plasma, corticosteroids and antifibrinolytics and by observation in the intensive care unit (ICU). Coagulopathy resolved after causal treatment with monovalent Tiger snake antivenom. CONCLUSION: The patient made good progress and was well on discharge from the ICU 26 h postenvenomation.

Tissue injury and the inflammatory response to pediatric cardiac surgery with cardiopulmonary bypass: a descriptive study.

BACKGROUND: There are few detailed descriptions of the inflammatory response to cardiac surgery with cardiopulmonary bypass (CPB) in children beyond 24 h postoperatively. This is especially true for the antiinflammatory cytokines and the extent of tissue injury. The aim of the current study was to describe the inflammatory and injury responses in uncomplicated pediatric cardiac surgery with CPB, where methylprednisolone and modified ultrafiltration (MUF) were used. METHODS: Blood samples were collected up to 48 h postoperatively. Cytokines (tumor necrosis factor-alpha and interleukin-6, -1beta, -10, and -1ra), complement (C3d and C4d) and coagulation system (prothrombin activation fragments 1 and 2 and antithrombin III) activation, neutrophil elastase, and the resulting tissue injury (creatine kinase, lactate dehydrogenase, alanine transaminase, amylase, and gamma-glutamyl transferase) were measured. RESULTS: The proinflammatory cytokine release varied widely, in contrast to a clear-cut antiinflammatory response. Cytokine concentrations did not decrease immediately after MUF, and no rebound increases later in the postoperative period were observed. The coagulation system, but not complement, was activated. There was a late release of C-reactive protein. Tissue injury could be quantified biochemically without evidence of hepatic or pancreatic dysfunction. CONCLUSION: In this group of uncomplicated subjects, the antiinflammatory cytokine and tissue injury responses were well defined, in contrast to a variable proinflammatory cytokine release. This was accompanied by activation of the coagulation system but not of complement. Concentrations of inflammatory mediators did not decrease immediately after MUF, and there was no evidence for rebound release later in the postoperative period.

Pediatric cardiac output measurement using surface integration of velocity vectors: an in vivo validation study.

OBJECTIVE: To test the accuracy and reproducibility of systemic cardiac output (CO) measurements using surface integration of velocity vectors (SIVV) in a pediatric animal model with hemodynamic instability and to compare SIVV with traditional pulsed-wave Doppler measurements. DESIGN: Prospective, comparative study. SETTING: Animal research laboratory at a university medical center. SUBJECTS: Eight piglets weighing 10-15 kg. INTERVENTIONS: Hemodynamic instability was induced by using inhalation of isoflurane and infusions of colloid and dobutamine. MEASUREMENTS: SIVV CO was measured at the left ventricular outflow tract, the aortic valve, and ascending aorta. Transit time CO was used as the reference standard. RESULTS: There was good agreement between SIVV and transit time CO. At high frame rates, the mean difference +/- 2 SD between the two methods was 0.01+/-0.27 L/min for measurements at the left ventricular outflow tract, 0.08+/-0.26 L/min for the ascending aorta, and 0.06+/-0.25 L/min for the aortic valve. At low frame rates, measurements were 0.06+/-0.25, 0.19+/-0.32, and 0.14+/-0.30 L/min for the left ventricular outflow tract, ascending aorta, and aortic valve, respectively. There were no differences between the three sites at high frame rates. Agreement between pulsed-wave Doppler and transit time CO was poorer, with a mean difference +/- 2 SD of 0.09+/-0.93 L/min. Repeated SIVV measurements taken at a period of relative hemodynamic stability differed by a mean difference +/-2 SD of 0.01+/-0.22 L/min, with a coefficient of variation = 7.6%. Intraobserver coefficients of variation were 5.7%, 4.9%, and 4.1% at the left ventricular outflow tract, ascending aorta, and aortic valve, respectively. Interobserver variability was also small, with a coefficient of variation = 8.5%. CONCLUSIONS: SIVV is an accurate and reproducible flow measurement technique. It is a considerable improvement over currently used methods and is applicable to pediatric critical care.

Doppler flow measurement using surface integration of velocity vectors (SIVV): in vitro validation.

Blood flow measurement using an improved surface integration of velocity vectors (SIVV) technique was tested in in vitro phantoms. SIVV was compared with true flow (12-116 mL/s) in a steady-state model using two angles of insonation (45 degrees and 60 degrees ) and two vessel sizes (internal diameter = 11 and 19 mm). Repeatability of the method was tested at various flow rates for each angle of insonation and vessel. In a univentricular pulsatile model, SIVV flow measured at the mitral inlet was compared to true flow (29-61 mL/s). Correlation was excellent for the 19-mm vessel (r(2)= 0.99). There was a systematic bias but close limits of agreement (mean +/- 2 SD = -24.1% +/- 7.6% at 45 degrees; +16.4% +/- 11.0% at 60 degrees ). Using the 11-mm vessel, a quadratic relationship was demonstrated between between SIVV and true flow (r(2) = 0.98-0.99), regardless of the angle of insonation. In the pulsatile system, good agreement and correlation were shown (r(2) = 0.94, mean +/- 2 SD = -4.7 +/- 10.1%). The coefficients of variation for repeated SIVV measurements ranged from 0.9% to 10.3%. This method demonstrates precision and repeatability, and is potentially useful for clinical measurements.

Movement of pulmonary artery catheters.

Intraluminal movements of pulmonary artery catheters are seldom considered, although they may have a significant impact on flow measurement and safety. The purpose of this study was to document the movements of these catheters within the heart cycle, and to establish whether any patterns existed. We analyzed two-dimensional real time echocardiography cross-sectional images of the human pulmonary artery in 20 patients, plotting the position of the intra-arterial catheter frame-by-frame onto a standardized template. We found that movement of the catheter within the pulmonary artery occurred in a seemingly random pattern. There was no movement pattern to the inferior right of the vessel, an area known to have complex velocity profiles and erroneous velocity measurements. The catheter moved substantially throughout the heart cycle, occasionally quite close to the vessel wall. We observed significant movement of the pulmonary artery catheter throughout the heart cycle, without any predictable pattern. Although we did not specifically investigate the effect of these movements on cardiac output, they imply that intra-arterial Doppler flow measurements from the pulmonary artery may be inaccurate, since a stable catheter position, and hence, a sample volume, cannot be ensured. Further speculation can be made on the implications of these movements in regard to thermodilution cardiac output and safety.