Non-traumatic bilateral epidural hematoma in a child with sickle cell anemia: A case report and a review of the literature.

OBJECTIVE: To report a rare case of spontaneous bilateral epidural hematoma (EDH) in a 10-year-old Nigerian child with sickle cell disease (SCD) and review the literature regarding this unusual complication. METHODS: We present a case of a pediatric patient with SCD who developed a spontaneous bilateral EDH and discuss the potential underlying mechanisms, management approaches, and outcomes. We also conducted a literature review of existing cases of spontaneous EDH in patients with SCD. RESULTS: Our patient initially presented with a subgaleal hematoma and underlying bilateral EDH, but she was sent home without any neurosurgical consultation. Two years later, she returned with altered consciousness and left-sided weakness, revealing an increased size of the EDH with a noticeable mass effect. She underwent a successful emergency bilateral craniotomy, with noticeable improvement in her level of consciousness and left-sided weakness post-operatively. In our literature review, we found 40 reported cases of spontaneous EDH in SCD patients, with a male predominance (82.5%). The average age of patients was 15.282 years. The most common hematoma location was bifrontal (20%) and the most reported symptom was headache (47.5%). Most patients (97.5%) were already known cases of SCD. Among those treated, 77.5% survived. CONCLUSION: Spontaneous bilateral EDH in SCD patients is an uncommon complication, with a variety of proposed pathophysiological mechanisms. Prompt recognition and appropriate management, either conservative or surgical, are crucial to improve outcomes. Our case and literature review underscore the importance of considering spontaneous EDH in SCD patients presenting with neurological symptoms, even in the absence of trauma. Further research is needed to elucidate the precise etiology, identify risk factors, and optimize management approaches for this rare complication in SCD patients.

Visual outcome of treating proliferative sickle cell retinopathy in 108 eyes.

AIM: To report treatment methods and visual outcome of treating proliferative sickle cell retinopathy (PSCR). DESIGN: Retrospective interventional. METHODS: Review of PSCR eyes treated between 2017 to 2022. Patient demographics, fundus findings at presentation, genotype, PSCR stage, treatment used, and visual outcome were assessed. RESULTS: 108 eyes of 88 consecutive patients were studied. Male: Female 48:40. Mean age: 38.91 (SD:12.52) years. Genotype: sickle cell haemoglobin C (SC) 83 eyes (76.9%), sickle cell haemoglobin S (SS) 19 eyes (17.6%), and sickle cell trait (AS) 6 eyes (5.5%). PSCR stages: 3: 15 eyes (11.0%), 4: 74 eyes (67.0%), and 5: 19 eyes (22.0%). Treatment methods: Intravitreal Injection (IVI) of anti-vascular endothelial growth factor (VEGF) only (27 eyes,25%), scatter retinal laser photocoagulation (SRLP) only (7 eyes, 6.5%), Vitrectomy + SRLP (29 eyes, 26.9%), IVI + SRLP (25 eyes, 23.1%), and Vitrectomy + IVI + SRLP (20 eyes, 18.5%). The treatment used correlated with PSCR stage (p = 0.000). IVI only was mostly used to treat stage 4 (81.4%), and SRLP only was used for stages 3 (42.9%) and 5 (57.1%). IVI + SRLP treated eyes had the best pre- and post-treatment vision. Vitrectomy + SRLP treated eyes had the most improved vision. SRLP only had least visual improvement. Fundus findings correlated with visual outcome (p = 0.003); but stage of PSCR, genotype and treatment used had no correlation (P > 0.05). CONCLUSION: Several options effectively treat PSCR. Visual outcome improved or remained same in 90.7% of treated eyes. Randomized controlled trials will determine the optimum treatment for each distinct presentation of PSCR. Treatment guidelines and a disease classification system of prognostic value are unmet needs.

Survival of total hip arthroplasty (THA) in sickle cell disease.

BACKGROUND: The objective of this study was to evaluate the outcome of THA done in patients with sickle cell disease at a single center, and compare with rest of the world before we could recommend routine THA in SCD patients. METHODS: In 92 patients, 117 THAs were performed in sickle cell patients. Seventy-six (76) patients had homozygous hemoglobin (Hgb SS) disease, whereas sixteen had sickle cell trait (Hgb AS). Patients with Grade III Ficat and above avascular necrosis of the head of femur (ANFH) with cementless porous-coated proximal femur fixation were included in this analysis. Harris hip score was modified (MHHS) and used for assessment of improvement and visual analog scale score (VAS), for pain assessment. RESULT: VAS improved from average pre-operative mean of 7 (7-9) to 2.5 (1-5). The average pre-operative MHHS was 44 (32-63), and it improved to 79 (71-88) in the final mean follow-up of 12.4 (4-18) years. Nine patients (9.7%) had complications and revision surgery was required in seven (5.9%) for aseptic loosening. CONCLUSION: Our analysis shows that THA in sickle cell disease is safe with average 12 years of follow-up, indicating that surgery in these young patients (≤ 25 years) is safe and should not be delayed.

Early splenectomy in a large cohort of children with sickle cell anemia: risks and consequences.

In children with sickle cell anemia (SCA), early splenic complications can require splenectomy, but the benefit-to-risk ratio and the age at which splenectomy may be safely performed remain unclear. To address this question, we analyzed the rate of post-splenectomy events in children with SCA splenectomized between 2000-2018 at the Robert Debré University Hospital, Paris, France. A total of 188 children underwent splenectomy, including 101 (11.9%) from our newborn cohort and 87 referred to our center. Median (Q1-Q3) age at splenectomy was 4.1 years (range 2.5-7.3 years), with 123 (65.4%) and 65 (34.6%) children splenectomized at ≥3 years of age or <3 years of age, respectively. Median postsplenectomy follow-up was 5.9 years (range 2.7-9.2 years) yielding 1192.6 patient-years (PY) of observation. Indications for splenectomy were mainly acute splenic sequestration (101 [53.7%]) and hypersplenism (75 [39.9%]). All patients received penicillin prophylaxis; 98.3% received 23-valent polysaccharic pneumococcal (PPV-23) vaccination, and 91.9% a median number of 4 (range 3-4) pneumococcal conjugate vaccine shots prior to splenectomy. Overall incidence of invasive bacterial infection and thrombo-embolic events were 0.005 / PY (no pneumococcal infections) and 0.003 / PY, respectively, regardless of age at splenectomy. There was an increased proportion of children with cerebral vasculopathy in children splenectomized <3 years of age (0.037 / PY vs. 0.011 / PY; P<0.01). A significantly greater proportion of splenectomized than non-splenectomized children were treated with hydroxycarbamide (77.2% vs. 50.1%; P<0.01), suggesting a more severe phenotype in children who present spleen complications. If indicated, splenectomy should not be delayed in children, provided recommended pneumococcal prophylaxis is available. Spleen complications in childhood may serve as a marker of severity.

Femoral Head Core Decompression and Bone Marrow Concentrate Injection in Pediatric Sickle-cell Related Avascular Necrosis.

BACKGROUND: Femoral head avascular necrosis affects 10% to 40% of patients with sickle cell disease (SCD). The purpose of this study was to evaluate the results of femoral head core decompression and bone marrow aspirate concentrate (CD-BMAC) injection in pediatric patients with SCD. METHODS: Eligible patients were enrolled in this retrospective study of patients undergoing CD-BMAC. Patients with SCD who were younger than 18 at the time of surgery and had >1 year of follow-up were included in this analysis. Hips were staged based on the Ficat system by 2 raters. The visual analog score for pain, hip outcome score, modified Harris hip score, and the University of California, Los Angeles activity score were used as patient-reported outcome measures preoperatively, at 5 to 9 months postoperatively, and final follow-up. Treatment failure was defined as total hip arthroplasty or visual analog score >3 at the final follow-up. RESULTS: Twenty-three hips in 17 patients were included, with a median age at the time of surgery of 15.8 years (interquartile range: 13.1 to 17.8 y). Patients were followed for 4.25 ± 1.7 years. Ten hips showed a 1-stage increase in the Ficat stage at the final follow-up, whereas 11 retained the same stage, and 1 hip had a 1-stage regression. All patient-reported outcome measures showed significant improvement from the preoperative visit to short-term follow-up, but the preoperative to final follow-up improvement was not significant. Six treatment failures were recorded, including 3 total hip arthroplasties and 3 painful hips at the final follow-up. In a multivariate logistic regression model, only skeletal maturity (odds ratio = 16.2, 95% CI: 1.44-183.0, P = 0.024) and femoral head collapse (odds ratio = 12.0, 95% CI: 1.1-130.5, P = 0.041) were significant predictors of treatment failure. CONCLUSIONS: In the largest study on pediatric SCD patients undergoing CD-BMAC, we found that CD-BMAC injection offers significant improvement in pain and functional outcomes in the short term, with a very low risk for complications. Skeletal maturity and femoral head collapse were significant predictors of treatment failure. Patients with a collapsed femoral head experienced functional deterioration over time after initial improvement, whereas precollapse hips maintained their functional improvement up to the latest follow-up. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

How does sickle cell disease affect the peri-operative outcome in patients undergoing total knee arthroplasty? A large-scale, National Inpatient Sample-based study.

INTRODUCTION: In view of the vaso-occlusive pathophysiology affecting osseous micro-circulation, sickle cell disease (SCD) is well known to present with diverse skeletal and arthritic manifestations. With prolonged life-expectancy over the past decades, there has been a progressive increase in the proportion of SCD patients requiring joint reconstructions. Owing to the paucity of evidence in the literature, the post-operative complication rates and outcome in these patients following total knee arthroplasty (TKA) are still largely unknown. METHODS: Based on the National Inpatient Sample (NIS) database (using ICD-10 CMP code), patients who underwent TKA between 2016 and 2019 were identified. The cohort were classified into two groups: A-those with SCD; and B-those without. The data on patients' demographics, co-morbidities, details regarding hospital stay including expenditure incurred, and complications were analyzed and compared. RESULTS: Overall, 558,361 patients underwent unilateral, primary TKA; among whom, 493 (0.1%) were known cases of SCD (group A). Group A included a significantly greater proportion of younger (60.14 ± 10.87 vs 66.72 ± 9.50 years; p < 0.001), male (77.3 vs 61.5%; p < 0.001); and African-American (88.2 vs 8.3%B; p < 0.001) patients, in comparison with group B. Group A patients were also at a significantly higher risk for longer duration of peri-operative hospital stay (p < 0.001), greater health-care costs incurred (p < 0.001), and greater need for alternative step-down health-care facilities (p < 0.001) following discharge. Among the SCD patients, 24.7%, 20.9% and 24.9% developed acute chest syndrome, pain crisis and splenic sequestration crisis, respectively during the peri-operative period. Group A patients had a statistically greater incidence of acute renal failure (ARF; p = 0.014), need for blood transfusion (p < 0.001) and deep vein thrombosis (DVT; p = 0.03) during the early admission period. CONCLUSION: The presence of SCD substantially lengthens the duration of hospital stay and enhances health care-associated expenditure in patients undergoing TKA. SCD patients are at significantly higher risk for systemic complications including acute chest syndrome, pain crisis, splenic sequestration crisis, acute renal failure, higher need for blood transfusions and deep venous thrombosis during the initial peri-operative period following TKA.

Outcomes of Patients With Sickle Cell Disease and Trait After Congenital Heart Disease Surgery.

BACKGROUND: Sickle cell disease (SCD) is a hemoglobinopathy that can cause multiorgan dysfunction. This study assessed the perioperative outcomes of patients undergoing operations for congenital heart disease who had SCD or sickle cell trait (SCT). METHODS: We performed a retrospective review of patients with SCD or SCT who had records in The Society of Thoracic Surgeons Congenital Heart Surgery Database between 2014 and 2019. The primary outcome was operative mortality. Secondary outcomes included postoperative complications. One-to-one propensity score matching was performed between the SCD and SCT groups and the control group for further analysis. RESULTS: Our study population consisted of 73, 411, and 36 501 patients in the SCD, SCT, and control groups, respectively. Median (25%-75% interquartile range) age at surgery was 2.8 (0.4-9.7), 0.60 (0.2-3.1), and 0.70 (0.2-6.4) years in the SCD, SCT, and control cohorts, respectively. Operative mortality, surgery duration, cardiopulmonary bypass time, and cross-clamp time were not significantly different among the 3 groups. The SCD group had a higher rate of postsurgical cardiac arrest than its propensity score-matched control group (5.5% vs 0%, P < .05); otherwise, there were no statistically significant differences in the outcomes between the SCD and SCT groups and their respective matched control groups. CONCLUSIONS: Operative mortality after cardiothoracic procedures in patients with SCD or SCT appeared similar to our control patients. While these patients may require unique perioperative management, they can undergo cardiac surgery without an observed increase in mortality.

Impact of sickle cell disease in shoulder arthroplasty: a matched cohort analysis.

BACKGROUND: Sickle cell disease (SCD) is a genetic disorder of abnormal hemoglobin synthesis that is known to cause glenohumeral avascular necrosis (AVN). Little has been published on the use of shoulder arthroplasty (SA) for the treatment of glenohumeral AVN in SCD. We report on the clinical and radiographic results and postoperative complications following SA in the patient cohort. METHODS: A retrospective review was performed identifying 17 primary SAs (9 hemiarthroplasties, 7 anatomic total SAs, and 1 reverse total SA) in patients with a confirmed diagnosis of SCD and a minimum of 2-year follow-up. This cohort was matched (1:2) according to age, sex, body mass index, type of prosthesis, and year of surgery with patients who had undergone hemiarthroplasty or total SA for osteoarthritis (OA) or reverse total SA for cuff tear arthropathy. Outcomes included the visual analog scale (VAS) for pain, American Shoulder and Elbow Surgeons score, range of motion, and strength measurements in forward elevation (FE), external rotation (ER), and internal rotation (IR). RESULTS: Our cohort included 9 (52.9%) men with a mean age of 43 yr. The average follow-up time was 5.9 yr. In patients with SCD, SA provided significant improvements in VAS pain (9.1-3.8; P < .001), FE (95°-128°; P < .001), ER (24°-38°; P < .001), IR score (3.2-5.2; P < .001), FE strength (4.2-4.8; P < .001), ER strength (4.1-4.7; P < .001), IR strength (4.1-4.7; P < .001), and American Shoulder and Elbow Surgeons scores (48.6-73.5; P < .001). When compared to the matched cohort, the SCD group demonstrated higher preoperative (9.1 vs. 3.8; P < .001) and postoperative VAS scores (3.8 vs. 1.3; P < .001). Other clinical outcomes demonstrated no significant differences. There were 5 (29%) complications, 2 (11.8%) episodes of sickle cell crisis, and 3 (18%) reoperations in the SCD cohort. When compared to the matched cohort, there were no statistical differences with respect to complications (29% vs. 12%; P = .140) or reoperations (18% vs. 12%; P = .387). CONCLUSIONS: SA is an effective treatment modality for glenohumeral AVN in patients with SCD. Patients may expect improvements in pain, function, motion, and strength. However, final postoperative pain relief may be less than those treated with SA without SCD. Unique perioperative management is necessary to mitigate the risk of postoperative sickle cell crises.

Impact of sickle cell disease on postoperative outcomes following total hip arthroplasty.

INTRODUCTION: Osteonecrosis (ON) of the femoral head is a common complication of sickle cell disease (SCD), frequently necessitating total hip arthroplasty (THA). Although THA is a common procedure with few complications when indicated for osteoarthritis (OA), patients with SCD have increased rates of complications. The purpose of this study is to determine the impact of SCD on outcomes and complications following THA. METHODS: Subjects were retrospectively identified using a national insurance claims database (PearlDiver Technologies) using CPT and ICD-9/10. Patients were included if they underwent THA with at least 2-year follow-up and were diagnosed with SCD and ON, ON without SCD, or OA without SCD. The SCD cohort was matched based on age, gender, Charlson Comorbidity Index, and obesity to the other 2 cohorts. 2-year revision rate and 90-day complication rates were analyzed using chi-square tests. RESULTS: Each cohort had 881 patients. The SCD cohort had significantly higher 90-day medical complications when compared to the ON without SCD and OA cohorts (p < 0.001). The SCD cohort had a higher rate of 2-year revision for PJI (5.0%) compared to the ON without SCD (2.8%) and OA (2.5%) groups (p = 0.019 and 0.005 respectively) and a higher rate of aseptic loosening (1.94%) compared to the ON without SCD cohort (0.68%; p = 0.021). CONCLUSIONS: Patients with SCD who undergo THA have an increased risk for short-term postoperative medical complications and 2-year aseptic loosening and PJI compared to ON patients without SCD and patients with OA. Given the magnitude of these risks, patient counseling and optimised perioperative care are essential.

Modifying priming techniques in cardiopulmonary bypass circuit in known case of sickle-cell trait undergoing open heart surgery.

Modifying cardiopulmonary bypass (CPB) circuit's priming technique before the onset of CPB in cardiac patients known with sickle-cell disease or sickle cell trait has been observed to be of substantial significance in dealing with such challenges without having any life-threatening consequences. We modified our routine heparinized crystalloid priming of the CPB circuit with partial exchange transfusion by adding donor blood (packed red blood cells), fresh frozen plasma (FFP), and bicarbonate. This has helped us bring down the overall sickle cell hemoglobin in the blood thereby reducing its risk of sickling.

An Overview of Solid Organ Transplantation in Patients With Sickle Cell Disease.

Sickle cell disease is a common genetic disorder affecting >300 000 people across the world. The vast majority of patients cared for in high-resource settings live well into adulthood, but many develop a high burden of disease complications. Good standard of care including disease-modifying agents and transfusion programs limits the number of patients who develop end-stage organ disease, but for those that do, the prognosis can be very poor. Solid organ transplantation is a well-established mode of treatment for patients with sickle cell disease and kidney or liver failure, but appropriate patient selection and perioperative management are important for achieving good outcomes. Hematopoietic stem cell transplantation and gene therapy may offer novel treatment options for adult patients with chronic organ damage in the future, but these are not yet widely available. For now, good, holistic care and early intervention of end-organ complications can minimize the number of patients requiring solid organ transplantation later in life.

Considerations in the Sickle Cell Patient Undergoing Hip Reconstructive Surgery.

Sickle cell disease (SCD) is a hemoglobinopathy that commonly has musculoskeletal effects including osteonecrosis of major joints (most often the hip) and medullary infarcts with resultant pain, functional limitations, and decreased quality of life. Patients with SCD may require surgical intervention, including total hip arthroplasty, frequently at a young age. The underlying pathologic process of SCD creates unique medical and surgical challenges that place these patients at increased risk of complications. This necessitates a multidisciplinary approach for providing surgical care to patients with SCD.

Preoperative Transfusion and Surgical Outcomes for Children with Sickle Cell Disease.

BACKGROUND: Current guidelines recommending preoperative transfusion to a hemoglobin level of 9 to 10 g/dL for patients with sickle cell disease (SCD) are based on imperfect evidence. The benefit of preoperative transfusion in children specifically is not known. This study aimed to evaluate whether preoperative RBC transfusion is associated with different rates of sickle cell crisis and surgical complications, compared with no preoperative transfusion, among children with SCD undergoing common abdominal operations. STUDY DESIGN: The NSQIP-Pediatrics database (2013 to 2019) was queried. Patients who underwent cholecystectomy, splenectomy, or appendectomy with a preoperative Hct level of less than 30% were included. The primary outcome was 30-day readmission for sickle cell crisis. Secondary outcomes were 30-day surgical complications and hospital length of stay. Propensity score matching methods were used to obtain two statistically similar cohorts of patients comprised of those who were preoperatively transfused and those who were not. RESULTS: Among 357 SCD patients, 200 (56%) received preoperative transfusion. In the matched cohort of 278 patients (139 per group), there was no statistically significant difference in 30-day readmission for sickle cell crisis in the transfused and non-transfused groups (5.8% vs 7.2%, p = 0.80). The rate of 30-day surgical complications did not differ between matched groups (10.8% vs 9.4%, p = 0.84). Subgroups defined by presenting Hct levels of 27.3% or greater or less than 27.3%, American Society of Anesthesiologists classification, wound class, and index operation were not associated with an altered risk of sickle cell crisis or surgical complications after preoperative transfusion compared with no transfusion. CONCLUSIONS: Preoperative transfusion for children with SCD undergoing semi-elective abdominal operations was not associated with improved outcomes. Prospective investigation is warranted to strengthen guidelines and minimize unnecessary perioperative transfusions in this population.

Simple open-heart surgery protocol for sickle-cell disease patients: a retrospective cohort study comparing patients undergoing mitral valve surgery.

OBJECTIVES: Sickle-cell disease (SCD) patients are considered to be at high risk from open-heart surgery. This study assessed the role of a simple sickling-prevention protocol. METHODS: Perioperative non-specific and SCD-specific morbidity and 30-day mortality are investigated in a retrospective cohort study on patients undergoing isolated mitral valve surgery. Patients with and without SCD were compared. In the SCD cohort, a bundle of interventions was applied to limit the risk of sickling: 'on-demand' transfusions to keep haemoglobin levels of around 7-8 g/dl, cardiopulmonary bypass (CPB) with higher blood flow and perfusion temperature, close monitoring of acid-base balance and oxygenation. RESULTS: Twenty patients with and 40 patients without SCD were included. At baseline, only preoperative haemoglobin levels differed between cohorts (8.1 vs 11.8 g/dl, P < 0.001). Solely SCD patients received preoperative transfusions (45.0%). Intraoperative transfusions were significantly larger in SCD patients during CPB (priming: 300 vs 200 ml; entire length: 600 vs 300 ml and 20 vs 10 ml/kg). SCD patients had higher perfusion temperatures during CPB (34.7 vs 33.0°C, P = 0.01) with consequently higher pharyngeal temperature, both during cooling (34.1 vs 32.3°C, P = 0.02) and rewarming (36.5 vs 36.2°C, P = 0.02). No mortality occurred, and non-SCD-specific complications were comparable between groups, but one SCD patient suffered from perioperative cerebrovascular accident with seizures, and another had evident haemolysis. CONCLUSIONS: SCD patients may undergo open-heart surgery for mitral valve procedures with an acceptable risk profile. Simple but thoughtful perioperative management, embracing 'on-demand' transfusions and less-aggressive CPB cooling is feasible and probably efficacious.

Liver Transplantation After Hematopoietic Stem Cell Transplant for the Treatment of Sickle Cell Disease: A Case Report.

Sickle cell anemia is the most common of the hemoglobinopathies, in which the abnormal hemoglobin formed in deoxygenation states undergoes a polymerization process with consequent erythrocyte deformation and vaso-occlusive events. The need for multiple blood transfusions, prolonged ineffective erythropoiesis, hemolysis, and increased iron absorption can cause iron overload in the liver, leading to liver fibrosis. Hematopoietic stem cell transplantation (HSCT) is currently the only treatment with a curative potential for this disease and can establish normal complete or partial donor-derived erythropoiesis and stabilize or restore function in affected organs, preventing further deterioration of function. However, it does not reverse preexisting liver fibrosis and siderosis. One of the possible complications of patients who undergo HSCT is chronic liver disease, which has a multifactorial cause, with iron overload being an important factor. In the long term, the prevalence of chronic liver disease in HSCT patients, including cirrhosis and its complications, can be significant. Solid organ transplantation after allogeneic hematopoietic cell transplantation for end-organ failure remains a very rare event. It may offer a valuable treatment strategy in selected recipients, although it is associated with significant morbidity and mortality. We report the case of a patient with sickle cell anemia who underwent HSCT and developed severe liver dysfunction requiring liver transplantation 13 years after the procedure. We found no previous report in the literature of orthotopic liver transplant after HCT for the treatment of sickle cell disease.

Revascularization Is Associated With a Reduced Stroke Risk in Patients With Sickle Cell-Associated Moyamoya Syndrome.

BACKGROUND: Moyamoya syndrome refers to a progressive stenosis of the internal carotid arteries and can be associated with sickle cell disease. These codiagnoses result in severe risk for stroke, even in patients on optimal medical management. Surgical revascularization has been shown to be safe in small case series. OBJECTIVE: To evaluate the efficacy of revascularization with direct comparison to a medically managed control group within a single institution. METHODS: A retrospective cohort study of medically managed vs surgically revascularized patients with moyamoya syndrome and sickle cell disease was conducted. Demographic data and outcomes including the number of prediagnosis, postdiagnosis, and postrevascularization strokes were collected. Risk factors for stroke were identified using a binary logistic regression model, and stroke rates and mortality between groups were compared. RESULTS: Of the 29 identified patients, 66% were medically managed and 34% underwent surgical revascularization (50% direct and 50% indirect). Calculated stroke rates were 1 per 5.37 (medical management), 1 per 3.43 (presurgical revascularization), and 1 per 23.14 patient-years (postsurgical revascularization). There was 1 surgical complication with no associated permanent deficits. No risk factors for stroke after time of diagnosis were found to be significant. CONCLUSION: The results of this study demonstrate that revascularization is associated with a significant reduction in stroke risk, both relative to prerevascularization rates and compared with medical management. According to these findings, surgical revascularization offers a safe and durable preventative therapy for stroke and should be pursued aggressively in this patient population.

Guideline on the peri-operative management of patients with sickle cell disease: Guideline from the Association of Anaesthetists.

Sickle cell disease is a multisystem disease characterised by chronic haemolytic anaemia, painful vaso-occlusive crises and acute and chronic end-organ damage. It is one of the most common serious inherited single gene conditions worldwide and has a major impact on the health of affected individuals. Peri-operative complications are higher in patients with sickle cell disease compared with the general population and may be sickle or non-sickle-related. Complications may be reduced by meticulous peri-operative care and transfusion, but unnecessary transfusion should be avoided, particularly to reduce the risk of allo-immunisation. Planned surgery and anaesthesia for patients with sickle cell disease should ideally be undertaken in centres with experience in caring for these patients. In an emergency, advice should be sought from specialists with experience in sickle cell disease through the haemoglobinopathy network arrangements. Emerging data suggest that patients with sickle cell disease are at increased risk of COVID-19 infection but may have a relatively mild clinical course. Outcomes are determined by pre-existing comorbidities, as for the general population.