Étienne de Médicis

Restrictive or Liberal Red-Cell Transfusion for Cardiac Surgery

BACKGROUND The effect of a restrictive versus liberal red‐cell transfusion strategy on clinical outcomes in patients undergoing cardiac surgery remains unclear. METHODS In this multicenter, open‐label, noninferiority trial, we randomly assigned 5243 adults undergoing cardiac surgery who had a European System for Cardiac Operative Risk Evaluation (EuroSCORE) I of 6 or more (on a scale from 0 to 47, with higher scores indicating a higher risk of death after cardiac surgery) to a restrictive red‐cell transfusion threshold (transfuse if hemoglobin level was <7.5 g per deciliter, starting from induction of anesthesia) or a liberal red‐cell transfusion threshold (transfuse if hemoglobin level was <9.5 g per deciliter in the operating room or intensive care unit [ICU] or was <8.5 g per deciliter in the non‐ICU ward). The primary composite outcome was death from any cause, myocardial infarction, stroke, or new‐onset renal failure with dialysis by hospital discharge or by day 28, whichever came first. Secondary outcomes included red‐cell transfusion and other clinical outcomes. RESULTS The primary outcome occurred in 11.4% of the patients in the restrictive‐threshold group, as compared with 12.5% of those in the liberal‐threshold group (absolute risk difference, ‐1.11 percentage points; 95% confidence interval [CI], ‐2.93 to 0.72; odds ratio, 0.90; 95% CI, 0.76 to 1.07; P<0.001 for noninferiority). Mortality was 3.0% in the restrictive‐threshold group and 3.6% in the liberal‐threshold group (odds ratio, 0.85; 95% CI, 0.62 to 1.16). Red‐cell transfusion occurred in 52.3% of the patients in the restrictive‐threshold group, as compared with 72.6% of those in the liberal‐threshold group (odds ratio, 0.41; 95% CI, 0.37 to 0.47). There were no significant between‐group differences with regard to the other secondary outcomes. CONCLUSIONS In patients undergoing cardiac surgery who were at moderate‐to‐high risk for death, a restrictive strategy regarding red‐cell transfusion was noninferior to a liberal strategy with respect to the composite outcome of death from any cause, myocardial infarction, stroke, or new‐onset renal failure with dialysis, with less blood transfused. (Funded by the Canadian Institutes of Health Research and others; TRICS III ClinicalTrials.gov number, NCT02042898.)

Technical report: optimal quantity of saline for epidural pressure waveform analysis

PurposeEpidural waveform analysis (EPWA) is a simple test to confirm the optimal placement of an epidural catheter. It relies on the transmission of the thecal pressure waveform through the epidural catheter. Little is known about the optimal volume of catheter injectate needed to optimize the EPWA test.MethodsIn a randomized controlled trial we compared three different catheters: stimulating, open-ended hole [S1]; stimulating, three-hole [S3]; non-stimulating three-hole [NS3]) in 60 patients in an unblinded pilot study. After catheter insertion using a loss of resistance to air technique, we recorded the dose response curve of EPWA and the presence of epidural pressure wave transmitted through the catheter to repeated injections of 2.5 mL saline boluses in the catheter to a total volume of 10 mL. All patients were followed by the acute pain service to confirm adequacy of postoperative epidural analgesia.ResultsThe S3 catheters were significantly more responsive (able to transmit a pulsatile waveform) compared to the S1 [P = 0.003 (S3) andP = 0.012 (NS3)] at low injectate volume, while there was no differences between the S3 catheters in their ability to transmit a waveform for EPWA (P = 0.25). There was no increase in responsiveness after 2.5 mL injected for S3 catheters and 5 mL for the S1 catheter. Three patients had soft catheters that did not transmit an epidural pulsative waveform.ConclusionsFor EPWAs, S3 epidural catheters are superior to S1 catheters for determining pulsative waveform transmission at low injectate volume. The optimal initial quantity of saline for EPWA is 5 mL regardless of the catheter type used.RésuméObjectifL’analyse d’une forme d’onde péridurale (EPWA -Epidural waveform analysis) est un test simple utilisé pour confirmer le positionnement optimal d’un cathéter péridural. Ce test s’appuie sur la transmission de l’onde de pression thécale à travers le cathéter péridural. Nous ne disposons que de très peu de connaissances concernant le volume optimal de la dose injectée dans le cathéter afin d’optimiser le test EPWA.MéthodeDans le cadre d’une étude randomisée contrôlée, nous avons comparé trois cathéters différents : stimulant, à embouchure ouverte [S 1]; stimulant, à trois ouvertures [S3]; non-stimulant, à trois ouvertures [NS3]. Soixante patients ont participé à cette étude pilote ouverte. Après l’insertion du cathéter à l’aide d’une technique de perte de résistance à l’air, nous avons enregistré la courbe de dose réponse d’EPWA ainsi que la présence d’une onde de pression péridurale transmise par le cathéter lors d’injections répétées de bolus salins de 2,5 mL dans le cathéter, pour atteindre un volume total de 10 mL. Tous les patients ont été suivis par le service de douleur aiguë afin de confirmer que l’analgésie péridurale postopératoire était adéquate.RésultatsLes cathéters S3 ont été significativement plus aptes à transmettre une forme d’onde pulsatile, par rapport aux S1 [P = 0,003 (S3) etP = 0,012 (NS3)] lorsque le volume injecté était bas, alors qu’aucune différence n’a été observée entre les cathéters S3 dans leur capacité à transmettre une forme d’onde pour l’EPWA (P = 0,25). Il n’y a eu aucune augmentation de la transmissibilité lorsque plus de 2,5 mL ont été injectés dans les cathéters S3 et 5 mL dans les cathéters S1. Trois patients ont eu des cathéters sou-ples qui n’ont pas transmis de forme d’onde pulsatile péridurale.ConclusionPour les tests d’EPWA, les cathéters périduraux S3 sont supérieurs aux cathéters S1 afin de déterminer la transmission d’une forme d’onde pulsatile à un bas volume injecté. La quantité initiale optimale de solution saline pour l’EPWA est 5 mL, quel que soit le cathéter utilisé.

MRI diagnosis of intracranial hypotension

To the Editor: We read with interest the case report “Postpartum postural headache due to superior sagittal sinus thrombosis mistaken for spontaneous intracranial hypotension” by Chilsholm and Campbell.1 In that report a patient was eventually diagnosed with a sagittal sinus thrombosis after undergoing a lumbar epidural blood patch (LEBP). Of note, the patient had a magnetic resonance imaging (MRI) of the brain prior to the LEBP reported as normal aside from evidence of venous congestion. MRI is emerging as a useful tool for recognizing intracranial hypotension (IH). MRI studies of patients with IH commonly show on post-contrast image abnormal, intense, diffuse, symmetric, contiguous dural-meningeal (pachymeningeal) enhancement.2 This enhancement usually involves much of the supratentorial and infratentorial intracranial dural mater, including the convexities, interhemispheric fissure, tentorium, and fax cerebri. Abnormal leptomeningeal enhancement is usually absent except in more acute states, when abnormal enhancement of the dural venous sinuses may be noted.2 It is unclear in the report if the initial MRI was performed with gadolinium contrast. If this was the case, it would have been unusual to pursue a diagnosis of IH with a MRI showing venous congestion with no post-contrast pachymeningeal enhancement. This would have alerted the clinician about the unlikely diagnosis of IH for the etiology of the patient’s headache and avoided her an unnecessary lumbar epidural blood patch.

Six-Month Outcomes after Restrictive or Liberal Transfusion for Cardiac Surgery

Background We reported previously that, in patients undergoing cardiac surgery who were at moderate‐to‐high risk for death, a restrictive transfusion strategy was noninferior to a liberal strategy with respect to the composite outcome of death from any cause, myocardial infarction, stroke, or new‐onset renal failure with dialysis by hospital discharge or 28 days after surgery, whichever came first. We now report the clinical outcomes at 6 months after surgery. Methods We randomly assigned 5243 adults undergoing cardiac surgery to a restrictive red‐cell transfusion strategy (transfusion if the hemoglobin concentration was <7.5 g per deciliter intraoperatively or postoperatively) or a liberal red‐cell transfusion strategy (transfusion if the hemoglobin concentration was <9.5 g per deciliter intraoperatively or postoperatively when the patient was in the intensive care unit [ICU] or was <8.5 g per deciliter when the patient was in the non‐ICU ward). The primary composite outcome was death from any cause, myocardial infarction, stroke, or new‐onset renal failure with dialysis occurring within 6 months after the initial surgery. An expanded secondary composite outcome included all the components of the primary outcome as well as emergency department visit, hospital readmission, or coronary revascularization occurring within 6 months after the index surgery. The secondary outcomes included the individual components of the two composite outcomes. Results At 6 months after surgery, the primary composite outcome had occurred in 402 of 2317 patients (17.4%) in the restrictive‐threshold group and in 402 of 2347 patients (17.1%) in the liberal‐threshold group (absolute risk difference before rounding, 0.22 percentage points; 95% confidence interval [CI], ‐1.95 to 2.39; odds ratio, 1.02; 95% CI, 0.87 to 1.18; P=0.006 for noninferiority). Mortality was 6.2% in the restrictive‐threshold group and 6.4% in the liberal‐threshold group (odds ratio, 0.95; 95% CI, 0.75 to 1.21). There were no significant between‐group differences in the secondary outcomes. Conclusions In patients undergoing cardiac surgery who were at moderate‐to‐high risk for death, a restrictive strategy for red‐cell transfusion was noninferior to a liberal strategy with respect to the composite outcome of death from any cause, myocardial infarction, stroke, or new‐onset renal failure with dialysis at 6 months after surgery. (Funded by the Canadian Institutes of Health Research and others; TRICS III ClinicalTrials.gov number, NCT02042898.)

Transfusion Requirements in Cardiac Surgery III (TRICS III): Study Design of a Randomized Controlled Trial

OBJECTIVES To determine if a restrictive transfusion threshold is noninferior to a higher threshold as measured by a composite outcome of mortality and serious morbidity. DESIGN Transfusion Requirements in Cardiac Surgery (TRICS) III was a multicenter, international, open-label randomized controlled trial of two commonly used transfusion strategies in patients having cardiac surgery using a noninferiority trial design (ClinicalTrials.gov number, NCT02042898). SETTING Eligible patients were randomized prior to surgery in a 1:1 ratio. PARTICIPANTS Potential participants were 18 years or older undergoing planned cardiac surgery using cardiopulmonary bypass (CPB) with a preoperative European System for Cardiac Operative Risk Evaluation (EuroSCORE I) of 6 or more. INTERVENTIONS Five thousand patients; those allocated to a restrictive transfusion group received a red blood cell (RBC) transfusion if the hemoglobin concentration (Hb) was less than 7.5 g/dL intraoperatively and/or postoperatively. Patients allocated to a liberal transfusion strategy received RBC transfusion if the Hb was less than 9.5 g/dL intraoperatively or postoperatively in the intensive care unit or less than 8.5 g/dL on the ward. MEASUREMENTS AND MAIN RESULTS The primary outcome was a composite of all-cause mortality, myocardial infarction, stroke, or new onset renal dysfunction requiring dialysis at hospital discharge or day 28, whichever comes first. The primary outcome was analyzed as a per-protocol analysis. The trial monitored adherence closely as adherence to the transfusion triggers is important in ensuring that measured outcomes reflect the transfusion strategy. CONCLUSION By randomizing prior to surgery, the TRICS III trial captured the most acute reduction in hemoglobin during cardiopulmonary bypass.

Anesthésie-réanimation en chirurgie cardiaque, 2e édition

Anesthésie-réanimation en chirurgie cardiaque sous la direction de Jean-Luc Fellahi est la deuxième édition d’un texte paru initialement en 2006. Anesthésiste-réanimateur pratiquant à l’Hôpital Cardiologique et Pneumologique Louis-Pradel de Lyon, le professeur Jean-Luc Fellahi a mis à contribution une équipe francophone internationale de 67 experts en différents aspects de l’anesthésie cardiaque dont 15 venant du Canada (Université McMaster de Hamilton, le Centre Hospitalier Universitaire de Montréal, l’Institut de Cardiologie de Montréal et l’Institut Universitaire de Cardiologie et Pneumologie de Québec). Ce texte à couverture souple se veut un survol complet de la pratique de l’anesthésie-réanimation cardiaque. Il est divisé en six parties (évaluation préopératoire, stratégies de prise en charge péri-opératoire, monitorage périopératoire, réanimation postopératoire, pathologies spécifiques et particularités) et 38 chapitres. Il n’est pas accompagné de supports visuels supplémentaires (DVD ou lien/site internet). Chaque chapitre est relativement court (le livre fait 587 pages) et est structuré avec une mise en situation dans un paragraphe initial sur fond gris, le texte du chapitre, et, à la fin avant la liste des références, une boite avec les points principaux à retenir. Des paragraphes sur fond gris mettent en évidence certains éléments clés à travers divers chapitre. Tel que mentionné, les chapitres sont plutôt court, donc il s’agit essentiellement de survol et non de textes exhaustifs sur chaque sujet. La liste de références à la fin de chapitre est bien mise à jour et permettra aux plus inquisitifs de satisfaire leur curiosité sur des points plus précis. Le support visuel (figure/tableau) est adéquat. L’ensemble de l’anesthésie-réanimation cardiaque est bien représenté : En plus des sujets habituels, on trouve en complément à la douleur aigüe, un chapitre sur la douleur chronique ainsi qu’un chapitre sur la réparation mitrale percutanée (Mitraclip) et un autre sur les implantation valvulaire aortique par cathétérisme (TAVI). Le niveau des connaissances est bien mis à jour pour 2014-2015: on retrouve des considérations contemporaines sur la ventilation protectrice, l’évaluation des désordres péri-opératoires de l’hémostase, les stratégies transfusionnelles, etc. Bien qu’essentiellement écrit par des auteurs européens, les problématiques traversent bien l’Atlantique et les anesthésiologistes nord-américains n’auront aucun problème à se retrouver dans ce texte. Le niveau du français est aussi facilement accessible pour le lecteur nord-américain. En résumé, il s’agit d’un texte agréable, complet et bien écrit. Le support visuel (figure/tableau) est adéquat mais pour certaines parties (comme pour le chapitre sur la place de l’échocardiographie trans-oesophagienne en chirurgie cardiaque) un complément sur site internet par exemple pourrait s’avérer utile. De part son format et son niveau, ce livre s’adresse principalement aux résidents et peut servir de texte d’introduction pour les anesthésiologistes plus avancé(e)s sur certains sujets précis.

From the Journal archives: Complications of transurethral prostatic surgery: back to the future?

John Desmond MBBS FRCP(C) Complications of transurethral prostatic surgery. Can Anaesth Soc J 1970; 17: 25-36. To review complications of transurethral resection of the prostate (TURP) as they pertain to anesthesiologists. In this article published in January 1970 in the Canadian Anaesthetists’ Society Journal, now the Canadian Journal of Anesthesia (the Journal), the author reviews complications relating to TURP, including age group, cardiovascular status, plasminogen activation, bacteremia, hemorrhage, too-light general anesthesia, perforation of the bladder, inadvertently high spinal anesthetic, the danger of using vasopressors, and burns. Complications involving the endocrine system, erection, adductor spasm, explosions, and hypothermia are also mentioned. Furthermore, there is a detailed discussion regarding the composition of the irrigation solution and the effects of its intravenous absorption on the cardiovascular system and on serum osmolality and natremia. The results of slow absorption of irrigation fluid at the prostatic level combined with good left-ventricular function are associated with slight dilutional hyponatremia (≤ 10 mEq·L−1) and a good outcome. Rapid absorption of irrigation fluid and/or poor left-ventricular function in the context of possible acute blood loss, hypotension following spinal anesthesia, or myocardial depression with general anesthesia can lead to a marked drop in osmolality and more severe dilutional hyponatremia. This may lead to cerebral edema, pulmonary edema, heart failure, and cardiovascular collapse. In a series of 72 randomly chosen patients at the author’s institution, 18 patients experienced a reduction in serum sodium of > 10 mEq·L−1; eight patients experienced a reduction of > 20 mEq·L−1, and two patients experienced a decrease in both osmolality and natremia, with both developing cerebral and pulmonary edema. With an understanding of the possible complications and physiological implications of TURP, anesthesiologist caring for such patients may help reduce adverse outcomes or decrease their impact with proper management. In the late 1960s, mortality at the author’s institution was reduced from 1.5-0.4% in three years.

Perioperative Two-Dimensional Transesophageal Echocardiography—A Practical Handbook

The author of this handbook, Annette Vegas, is currently Director, Perioperative Transesophageal Echocardiography (TEE) at the Toronto General Hospital. Dr. Vegas is the director of the Toronto Perioperative TEE Symposium and is well-known in the Canadian field of TEE. This small spiral-bound handbook is divided into 11 chapters that cover content extending from basic TEE knowledge foundations (the 20 basic TEE views) to more advanced specialized images and topics in TEE. Examples of the latter include advanced TEE views, TEE images of various congenital heart diseases, and TEE-related images in patients with ventricular assist devices. The chapters in this concise text are clearly subdivided so the reader can easily search specific topics without getting lost in the details. With more than 450 clinical images and illustrations, including three-dimensional TEE images, this work is a visual success. The quality and depth of information incorporated into such a succinct package makes this text quite a tour de force. This reviewer found an earlier version of this text, edited in 2003 by the University Health Network in Toronto, incredibly useful for discussions with residents in training on a variety of perioperative TEE topics. Additionally, this previous version established itself as a wonderful quick reference guide at the bedside, especially when using TEE as a diagnostic tool or guide to therapy while caring for high-risk patients. This new edition is a considerable enhancement to the previous version. It is designed as an on-the-spot reference for echocardiographers whose experience ranges from novice to expert. As TEE continues to evolve, in addition to imaging, future editions will need to incorporate more three-dimensional echocardiography images as well as a short section on port-access cardiac surgery (the topic of transcatheter valves has already been addressed). Overall, this text is a welcome and practical addition to the TEE literature. The handy size of this spiralbound tome makes it an ideal pocket-sized quick reference source to carry around during clinical duties.

Coronary left ventricular outflow tract fistula after resection of a subaortic valve membrane

A 34-yr-old woman was admitted to hospital for resection of a subaortic valve membrane and repair of an ascending aortic aneurysm (Figs. 1 and 2). At 8 months of age, the patient underwent resection of a subaortic valve membrane and closure of a patent ductus arteriosus. On this occasion, the patient underwent resection of the subaortic membrane, ventricular myomectomy, and replacement of the ascending aorta with an aortic valve-sparing technique. At the end of surgery, after unclamping the aorta, a small, central aortic insufficiency grade 1/4 was observed, with no ventricular septal defect. The mitral valve was normal, but an unusual subaortic color Doppler flow was discovered (Fig. 3), which had not been present preoperatively. This color flow was diastolic and appeared to originate from a branch of the left anterior descending (LAD) coronary artery draining into the left ventricular outflow tract (LVOT) just inferior to the aortic valve (Video 1, midesophageal inflow-outflow view). Pulsed-wave Doppler confirmed the typical diastolic flow pattern of the LAD coronary artery (Fig. 4). A fistula from a perforator septal branch of the interventricular septum was presumed to have been responsible for this unusual color flow (also known as a truncated septal perforator). This fistula was not present on the preoperative coronary angiogram. Weaning from bypass was easy and the left segmental ventricular function remained normal. The surgeon decided not to intervene on this new finding, and the patient had an uneventful recovery. Coronary artery fistulas may be congenital or acquired due to trauma or surgical interventions. These fistulas are quite rare in adults. In a series of 33,600 coronary angiograms in a general population, only 34 (0.1%) were observed, with a good prognosis. Surgical septal myomectomy may also result in a ventricular septal defect (perimembranous-like ventricular septal defect). In such case, the color flow pattern will be seen between the LVOT and the right ventricle in the mid-esophageal long-axis Electronic supplementary material The online version of this article (doi:10.1007/s12630-009-9115-9) contains supplementary material, which is available to authorized users.

Cannabinoids for postoperative analgesia

To the Editor: We read with interest the article on the effects of nabilone on postoperative pain by Pierre Beaulieu.1 While it is unfortunate that his results did not generate firm conclusions, we believe that descriptive subgroup analyses may have yielded some important information regarding the effects of nabilone on postoperative morphine consumption and side-effects. Nineteen of the 41 patients in the study underwent hysterectomy or myomectomy, which is a surgically homogenous patient population for whom it would have been interesting to have compared the effects of placebo, ketoprofen and nabilone doses of 1 and 2 mg on morphine consumption, visual analogue scale (VAS) scores and secondary outcomes. Eighteen of the 41 patients underwent orthopedic surgery (hip or knee arthroplasty), which represents a different surgical population of potentially greater heterogeneity, with an additional confounding factor that knee arthroplasties are associated with more postoperative pain compared with hip arthroplasty.2 A greater number of knee arthroplasty patients in the nabilone 2 mg group could explain why there is an apparent possible hyperalgesic effect of nabilone. Hence, it would be interesting to know the breakdown of knee/hip arthroplasty by study group (placebo, ketoprofen and nabilone 1 and 2 mg), and the results (morphine consumption, VAS scores and secondary outcomes) according to the orthopedic procedure and study group.