David T. Neilipovitz

A Randomized Trial of Tranexamic Acid to Reduce Blood Transfusion for Scoliosis Surgery

Pediatric patients who undergo posterior spinal fusion surgery to correct scoliosis often require multiple blood transfusions. Tranexamic acid is a synthetic antifibrinolytic drug that reduces transfusion requirements in cardiac surgery and total knee arthroplasty. We evaluated the efficacy of prophylactic tranexamic acid to reduce perioperative blood transfusion requirements in a prospective, double-blinded, placebo control study. Forty patients, 9–18 yr of age, were randomized to either tranexamic acid (initial dose of 10 mg/kg and infusion of 1 mg · kg−1 · h−1) or placebo (isotonic saline). Perioperative management was standardized. A uniform transfusion threshold for noncell saved red blood cells was 7.0 g/dL. The total amount of blood transfused in the perioperative period was significantly reduced in the Tranexamic group (P = 0.045). No thrombotic complications were detected in either group. The administration of prophylactic tranexamic acid in patients with scoliosis undergoing posterior spinal fusion surgery has the potential to reduce perioperative blood transfusion requirements.

No evidence for decreased incidence of aspiration after rapid sequence induction

PurposeThe purpose of this structured, evidence-based, clinical update was to determine if rapid sequence induction is a safe or effective technique to decrease the risk of aspiration or other complications of airway management.SourceIn June 2006 a structured search of medline from 1966 to present using OVID software was undertaken with the assistance of a reference librarian. Medical subject headings and text words describing rapid sequence induction or intubation (RSI), crash induction or intubation, cricoid pressure and emergency airway intubation were employed. OVID’s therapy (sensitivity) algorithm was used to maximize the detection of randomized trials while excluding non-randomized research. The bibliographies of eligible publications were hand-searched to identify trials not identified in the electronic search.Principal findingsA total of 184 clinical trials were identified of which 163 were randomized controlled trials (RCTs). Of these clinical trials, 126 evaluated different drug regimens with 114 being RCTs. Only 21 clinical trials evaluated non-pharmacologic aspects of the RSI with 18 RCTs identified. A parallel search found 52 trials evaluating cricoid pressure (outside of the context of an RSI technique) with 44 classified as RCTs. Definitive outcomes such as prevention of aspiration and mortality benefit could not be evaluated from the trials. Likewise, the impact on adverse outcomes of the different components of RSI could not be ascertained.ConclusionAn absence of evidence from RCTs suggests that the decision to use RSI during management can neither be supported nor discouraged on the basis of quality evidence.RésuméObjectifCette mise à jour clinique structurée, basée sur des données probantes, avait pour objectif de déterminer si l’induction en séquence rapide est une technique sécuritaire ou efficace pour réduire le risque d’inhalation ou d’autres complications de prise en charge des voies respiratoires.SourceUne recherche structurée de MEDLINE, allant de 1966 à nos jours, à l’aide du logiciel OVID, a été entreprise en juin 2006 avec l’assistance d’un bibliothécaire documentaliste. Les titres de sujets et les termes de textes médicaux décrivant l’induction ou l’intubation en séquence rapide (RSI), la «crash induction» ou intubation, la pression cricox00CF:dienne et l’intubation des voies respiratoires en urgence ont été utilisés. L’algorithme de thérapie (sensibilité) d’OVID a servi à maximiser la détection d’études randomisées tout en excluant les recherches non randomisées. Les bibliographies des publications admissibles ont été cherchées manuellement pour identifier les études qui n’avaient pas été relevées par la recherche électronique.Constatations principalesAu total, 184 études cliniques ont été identifiées, desquelles 163 étaient des études randomisées contrôlées (RCT). De ces études cliniques, 126 ont évalué différents régimes médicamenteux, 114 étant des RCT. Seules 21 études cliniques ont évalué des aspects non pharmacologiques de l’induction en séquence rapide, dont 18 étaient des RCT. Une recherche parallèle a mis en évidence 52 études évaluant la pression cricoÏdienne (hors du contexte d’une technique de RSI), dont 44 étaient classées comme RCT. Des pronostics définitifs, tels que la prévention d’une inhalation et les bienfaits par rapport à la mortalité, n’ont pas pu être évalués à partir des études. De même, l’impact sur les devenirs indésirables des différentes composantes de la RSI n’a pas pu être déterminé.ConclusionUn manque de données probantes issues de RCT suggère que la décision d’utiliser la RSI pendant la prise en charge d’un patient ne peut être ni recommandée ni déconseillée sur la base de données probantes de qualité.

The effect of perioperative aspirin therapy in peripheral vascular surgery : A decision analysis

Patients who undergo infrainguinal revascularization surgery are at increased risk for perioperative thrombotic complications. Aspirin decreases thrombotic events in the nonoperative setting; however, aspirin is often discontinued to avoid perioperative hemorrhagic complications. We used a decision analysis to determine whether aspirin should be discontinued before infrainguinal revascularization surgery. Two strategies were compared: aspirin cessation 2 wk before surgery and aspirin continuation throughout the perioperative period. Clinical events examined included myocardial infarction, thrombotic cerebrovascular accident, hemorrhagic cerebrovascular accident, gastrointestinal hemorrhage, and incisional hemorrhagic complications. Event rates and effect of aspirin were obtained by using MEDLINE. The outcomes were perioperative mortality, life expectancy, and quality-adjusted life expectancy. According to the model, continued aspirin use decreased perioperative mortality rates from 2.78% to 2.05%. Continued aspirin use increased life expectancy from 14.83 to 14.89 yr and increased quality-adjusted life expectancy from 14.72 to 14.79 yr. Aspirin increased the number of hemorrhagic complications by 2.46%, primarily because of an increased incidence of non-life-threatening complications.

Cell salvage does not minimize perioperative allogeneic blood transfusion in abdominal vascular surgery: a systematic review.

PurposeTo determine whether the use of cell salvage reduces the proportion of patients receiving at least one unit of allogeneic packed red blood cells during the perioperative period of an elective vascular surgery.SourceWe identified all relevant articles through the combined use of electronic searches of the MEDLINE and EMBASE databases, the Cochrane library as well as hand searching of all randomized clinical trials and review articles. The electronic search included articles published between 1966 and April 2001. The search included textword searches using “autotransfusion,” “cell salvage,” “device,” or Medical Subject Headings “autologous blood transfusion” or a “randomized controlled trials” filter.Principal findingsFive randomized controlled trials (RCT) were identified involving cell salvage and vascular surgeries. In infra renal abdominal aortic aneurysm surgery the risk ratio (the risk of receiving at least one unit of allogeneic red cells) was 0.37 [95% confidence intervals (CI) of 0.06 to 2.36]. In elective aorto-femoral bypass surgery the risk ratio was 0.97 (95% CI of 0.66 to 1.42). The pooled risk ratio for cell salvage in vascular surgery was 0.67 (95% CI of 0.35 to 1.28).ConclusionCell salvage, a commonly used technique to recover red cells from the operative field, has been the subject of several studies in vascular surgery. There is insufficient evidence to recommend the routine use of cell salvage in elective abdominal aortic aneurysm and aorto-femoral bypass surgeries. A large RCT would elucidate whether cell salvage is effective as a blood conservation technique.RésuméObjectifDéterminer si la récupération de sang réduit le nombre de patients qui recevront au moins une unité de concentré de globules rouges allogènes en période périopératoire d’une intervention chirurgicale vasculaire réglée.SourceLes articles pertinents ont été repérés par des recherches électroniques combinées dans MEDLINE et EMBASE, la bibliothèque Cochrane et une recherche manuelle des essais cliniques randomisés et des exposés de synthèse. La recherche électronique comprend des articles publiés entre 1966 et avril 2001 à partir des termes «autotransfusion», «cell salvage», «device» ou de mots clés du domaine médical comme «autologous blood transfusion» ou d’un filtre sur les «randomized controlled trials».Constatations principalesNous avons trouvé cinq études randomisées et contrôlées (ERC) comportant la récupération de sang et la chirurgie vasculaire. L’opération d’un anévrysme aortique abdominal infrarénal présentait un taux de risque (le risque de recevoir au moins une unité de globules rouges allogènes) de 0,37 [intervalle de confiance (IC) de 95 % de 0,06 à 2,36]. Le risque lié au pontage aortofémoral réglé était de 0,97 (IC de 95 % de 0,66 à 1,42). Le risque commun en chirurgie vasculaire était de 0,67 (IC de 95 % de 0,35 à 1,28).ConclusionLa récupération de sang, couramment utilisé pour conserver les globules rouges provenant du champ opératoire, a fait l’objet de quelques études en chirurgie vasculaire. Il n’y a pas de preuve suffisante pour recommander la récupération régulière de sang lors d’opérations pour anévrysme aortique abdominal et de pontages aorto-fémoraux. Une importante ERC pourrait préciser si la récupération de sang est efficace comme technique de conservation du sang.

STAR VaS--Short Term Atorvastatin Regime for Vasculopathic Subjects: a randomized placebo-controlled trial evaluating perioperative atorvastatin therapy in noncardiac surgery.

PurposeEvidence suggests that statins reduce cardiovascular complications in patients undergoing noncardiac surgery, although questions remain regarding the mechanism of benefit and the preferred dosing strategy. In this trial, we evaluated the perioperative effects on C-reactive protein (CRP) that resulted from starting atorvastatin within seven days of noncardiac surgery. The objective was to identify anti-inflammatory effects of atorvastatin prior to conducting a large randomized trial with clinical end points.MethodsIn a single centre, parallel group, placebo-controlled trial, sixty high cardiac risk participants over age 45xa0yr undergoing noncardiac surgery were assigned randomly to one of three groups to receive atorvastatin 80xa0mg (A) and/or placebo (P). Group AA (nxa0=xa026) received atorvastatin seven days before surgery, the day of surgery, and for seven days post surgery. Group PA (nxa0=xa017) received placebo seven days before surgery, atorvastatin on the day of surgery, and atorvastatin for seven days post surgery. Group PP (nxa0=xa017) received placebo at all times. All participants, health care professionals, research assistants, and outcome adjudicators were masked to treatment allocation. Analyses were by intention to treat. The primary outcome was the C-reactive protein level at 48xa0hr.ResultsFifty-six participants completed the 30-day follow-up. The mean (standard deviation) changes in CRP levels from baseline at 48xa0hr in Groups AA, PA, and PP were 141.0 (72.4), 153.5 (42.2), and 111.2 (84.6), respectively. The mean differences (95% confidence interval) at 48xa0hr for AA vs PA, AA vs PP, and PA vs PP were: −20.1 (−81.2 to 41.1), 22.7 (−31.7 to 77.2), and 42.8 (−20.0 to 105.7), respectively, adjusting for baseline CRP, type of procedure, presence of coronary artery disease, use of medications, and for multiple comparisons using Tukey’s method.ConclusionsAdministration of atorvastatin, initiated within seven days preoperatively, was not associated with clinically significant reductions in CRP levels. (ClinicalTrials.gov number, NCT00967434).RésuméObjectifDes données probantes suggèrent que les statines réduisent les complications cardiovasculaires chez des patients subissant une chirurgie non cardiaque bien que des questions demeurent concernant le mécanisme de ce bénéfice et la meilleure stratégie posologique à adopter. Au cours de cette étude, nous avons évalué les effets périopératoires sur la protéine C-réactive (CRP) résultant d’une prise d’atorvastatine commençant dans les sept jours précédant une chirurgie non cardiaque. L’objectif était d’identifier les effets anti-inflammatoires de l’atorvastatine avant de mener une grande étude randomisée comportant des critères cliniques d’évaluation.MéthodesSoixante participants d’un seul centre, à risque cardiaque élevé, âgés de plus de 45xa0ans et devant subir une chirurgie non cardiaque, ont participé à une étude randomisée contre placebo et à groupes parallèles; ils ont été randomisés dans l’un des trois groupes pour y recevoir de l’atorvastatine 80xa0mg (A) et/ou un placebo (P). Les patients du groupe AA (nxa0=xa026) ont reçu de l’atorvastatine pendant sept jours avant la chirurgie, le jour de la chirurgie, et pendant sept jours aprèsxa0l’intervention chirurgicale. Les patients du groupe PA (nxa0=xa017) ont reçu un placebo pendant sept jours avant la chirurgie, de l’atorvastatine le jour de la chirurgie et pendant sept jours aprèsxa0l’intervention chirurgicale. Les patients du groupe PP (nxa0=xa017) ont reçu un placebo pendant toute la durée de l’étude. Tous les participants (professionnels de soins de santé, assistants de recherche et évaluateurs des résultats) ignoraient l’assignation au groupe de traitement. Les analyses ont été réalisées sur l’intention de traiter. Le principal critère d’évaluation était le taux de protéine C-réactive à 48xa0heures.RésultatsCinquante-six participants ont terminé le suivi de 30xa0jours. Les variations moyennes (écart-type) des concentrations de CRP à 48xa0heures par rapport à la ligne de base dans les groupes AA, PA et PP ont été, respectivement, de 141,0 (72,4), 153,5 (42,2) et de 111,2 (84,6). Les différences moyennes (intervalle de confiance à 95 %) à 48xa0heures pour les groupes AA contre PA, AA contre PP et PA contre PP ont été, respectivement: −20,1 (−81,2 à 41,1), 22,7 (−31,7 à77,2), et 42,8 (−20,0 à 105,7), après ajustement pour la CRP à la ligne de base, le type d’intervention, la présence d’une coronaropathie, l’utilisation de médicaments et pour les comparaisons multiples selon la méthode de Tukey.ConclusionsL’administration d’atorvastatine, débutée dans les sept jours précédant une intervention chirurgicale n’a pas été associée à des baisses cliniquement significatives des concentrations de CRP. (Numéro ClinicalTrials.gov: NCT00967434).

Blood Transfusion and Sepsis

The TRICC trial [104] demonstrated that a transfusion trigger of 7.0 g/dl and maintenance of hemoglobin concentrations between 7.0 and 9.0 g/dl was at worst equivalent and very likely superior to the more liberal use of red cells. A restrictive strategy is truly a superior therapy because clinical outcomes are superior, transfusions are decreased by 54% and costs are minimized. Given conflicting evidence, the optimal transfusion policy for septic patients is not known. The increased demands imposed by sepsis along with its impairment of the normal adaptive process to anemia would suggest that severely infected patients should have a more liberal transfusion practice as compared to nonseptic patients. The potential problems with allogeneic blood products however limits one’s enthusiasm for an aggressive transfusion practice. Thus, the best approach would be to limit the need to transfuse but to transfuse the best product available if a transfusion is required. We anxiously await the results of further trials with EPO, different RBC products, and other studies to confirm the results observed in the TRICC trial.

Dynamic Assessment of Fluid Responsiveness in Surgical ICU Patients Through Stroke Volume Variation is Associated With Decreased Length of Stay and Costs: A Systematic Review and Meta-Analysis

Static indices, such as the central venous pressure, have proven to be inaccurate predictors of fluid responsiveness. An emerging approach uses dynamic assessment of fluid responsiveness (FT-DYN), such as stroke volume variation (SVV) or surrogate dynamic variables, as more accurate measures of volume status. Recent work has demonstrated that goal-directed therapy guided by FT-DYN was associated with reduced intensive care unit (ICU) mortality; however, no study has specifically assessed this in surgical ICU patients. This study aimed to conduct a systematic review and meta-analysis on the impact of employing FT-DYN in the perioperative care of surgical ICU patients on length of stay in the ICU. As secondary objectives, we performed a cost analysis of FT-DYN and assessed the impact of FT-DYN versus standard care on hospital length of stay and mortality. We identified all randomized controlled trials (RCTs) through MEDLINE, EMBASE, and CENTRAL that examined adult patients in the ICU who were randomized to standard care or to FT-DYN from inception to September 2017. Two investigators independently reviewed search results, identified appropriate studies, and extracted data using standardized spreadsheets. A random effect meta-analysis was carried out. Eleven RCTs were included with a total of 1015 patients. The incorporation of FT-DYN through SVV in surgical patients led to shorter ICU length of stay (weighted mean difference [WMD], −1.43d; 95% confidence interval [CI], −2.09 to −0.78), shorter hospital length of stay (WMD, −1.96d; 95% CI, −2.34 to −1.59), and trended toward improved mortality (odds ratio, 0.55; 95% CI, 0.30-1.03). There was a decrease in daily ICU-related costs per patient for those who received FT-DYN in the perioperative period (WMD, US

Substantial variation of both opinions and practice regarding perioperative fluid resuscitation

−1619; 95% CI, −2173.68 to −1063.26). Incorporation of FT-DYN through SVV in the perioperative care of surgical ICU patients is associated with decreased ICU length of stay, hospital length of stay, and ICU costs.