Preoperative blood transfusions for sickle cell disease

Abstract

Background Sickle cell disease is one of the commonest severe monogenic disorders in the world, due to the inheritance of two abnormal haemoglobin (beta globin) genes. Sickle cell disease can cause severe pain, significant end-organ damage, pulmonary complications, and premature death. Surgical interventions are more common in people with sickle cell disease, and occur at much younger ages than in the general population. Blood transfusions are frequently used prior to surgery and several regimens are used but there is no consensus over the best method or the necessity of transfusion in specific surgical cases. This is an update of a Cochrane review first published in 2001. Objectives To determine whether there is evidence that preoperative blood transfusion in people with sickle cell disease undergoing elective or emergency surgery reduces mortality and perioperative or sickle cell-related serious adverse events. To compare the effectiveness of different transfusion regimens (aggressive or conservative) if preoperative transfusions are indicated in people with sickle cell disease. Search methods We searched for relevant trials in The Cochrane Library, MEDLINE (from 1946), Embase (from 1974), the Transfusion Evidence Library (from 1980), and ongoing trial databases; all searches current to 23 March 2016. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register: 18 January 2016. Selection criteria All randomised controlled trials and quasi-randomised controlled trials comparing preoperative blood transfusion regimens to different regimens or no transfusion in people with sickle cell disease undergoing elective or emergency surgery. There was no restriction by outcomes examined, language or publication status. Data collection and analysis Two authors independently assessed trial eligibility and the risk of bias and extracted data. Main results Three trials with 990 participants were eligible for inclusion in the review. There were no ongoing trials identified. These trials were conducted between 1988 and 2011. The majority of people included had haemoglobin (Hb) SS SCD. The majority of surgical procedures were considered low or intermediate risk for developing sickle cell-related complications. Aggressive versus simple red blood cell transfusions One trial (551 participants) compared an aggressive transfusion regimen (decreasing sickle haemoglobin to less than 30%) to a simple transfusion regimen (increasing haemoglobin to 100 g/l). This trial re-randomised participants and therefore quantitative analysis was only possible on two subsets of data: participants undergoing cholecystectomy (230 participants); and participants undergoing tonsillectomy or adenoidectomy surgeries (107 participants). Data were not combined as we do not know if any participant received both surgeries. Overall, the quality of the evidence was very low across different outcomes according to GRADE methodology. This was due to the trial being at high risk of bias primarily due to lack of blinding, indirec...

Preoperative transfusion versus no transfusion policy in sickle cell disease patients: a randomized trial

“…There is a low quality evidence that preoperative transfusion may prevent development of acute chest syndrome, but it might increase the risk of circulatory overload. 21 However, preoperative transfusion was not protective in the current study, as none of our patients in the non-transfusion arm developed ACS, compared to one case in the other arm. Of note, our enrolled patients represent a relatively low risk population overall.…”

“…The authors found no difference between aggressive (defined as bringing Hb S level to less than 30%) and conservative (defined as increasing the total Hb to more than 10 gm/dL) transfusion strategies as regards mortality and postoperative complications. Despite paucity of clinical trials and low quality evidence, Estcourt et al stated that there was no difference in mortality and postoperative VOC between people receiving preoperative transfusions and those receiving no preoperative transfusions. There is a low quality evidence that preoperative transfusion may prevent development of acute chest syndrome, but it might increase the risk of circulatory overload .…”

“…Despite paucity of clinical trials and low quality evidence, Estcourt et al stated that there was no difference in mortality and postoperative VOC between people receiving preoperative transfusions and those receiving no preoperative transfusions. There is a low quality evidence that preoperative transfusion may prevent development of acute chest syndrome, but it might increase the risk of circulatory overload . However, preoperative transfusion was not protective in the current study, as none of our patients in the non‐transfusion arm developed ACS, compared to one case in the other arm.…”

The cause of the stroke: a diagnostic uncertainty

“…Although there appears to be no specific contraindications against its use, it is known that patients with SCD have an increased risk of intracranial haemorrhage and this should be considered before the use of such agents 7. The use of red blood cell exchange transfusion is recommended as it decreases HbS concentration, which cause the procoagulant and adhesive properties as well as maximising the delivery of oxygen and thereby decreasing vaso-occlusion 9. A post-transfusion target usually consists of a Hb level of above 10 g/dL and HbS percentage of less than 30 4.…”

Perioperative care of children with sickle cell disease: A systematic review and clinical recommendations

“…Furthermore, the stringent criteria imposed by systematic reviews have sometimes hindered more argumentative presentations and discussions of the available evidence. Three recent Cochrane reviews on the role of preoperative transfusions for SCD patients undergoing surgery, unfortunately provided solely the observation that “insufficient evidence from randomized trials” is available to determine whether a conservative or aggressive approach is more beneficial in preventing complications in SCD patients . While important, these statements are concretely of little help to healthcare providers in their daily decision‐making, and sometimes fail to underline the main clinical message (ie, transfusions should be considered and discussed for patients with SCD prior to surgical procedures).…”