Blood transfusion and 30-day readmission rate in adult patients hospitalized with sickle cell disease crisis

Beyond Childhood: Adult and Adolescent Sickle Cell Disease and Outcomes in Northern Ghana

Background

Adults and adolescents face different barriers to healthcare utilization compared to children.

Objective

To describe adult and adolescent sickle cell disease (SCD) and outcomes in northern Ghana.

Methods

This was a retrospective cohort study of SCD patients aged 13 years and above, admitted between January 1, 2021 and December 31, 2022 at the Komfo Anokye Teaching Hospital. The data was summarized with descriptive statistics and a multivariate logistics regression analysis was fitted to identify factors independently associated with prolonged hospital stay of more than 4 days.

Results

Of the 326 admissions, 68.9% regularly attended their sickle cell clinics. Approximately 3% of all admissions into the internal medicine ward were due to SCD. Commonest complications observed were painful vaso-occlusive crisis (VOC) (78.1%), infection (51.2%), and hyperhemolysis (24.0%). Presented as adjusted odds ratio (95% CI), the predictors of prolonged hospital stay were: presence of comorbidities, 2.71 [(1.28, 5.97), p = 0.011]; infection, 1.78 [(1.08, 2.94), p = 0.024]; acute chest syndrome, 2.42 [(1.22, 4.970), p = 0.013]; hyperhemolysis, 2.02 [(1.08, 3.80), p = 0.028]; sequestration crisis, 3.80 [(1.50, 11.0), p = 0.008]; and requirement for transfusion, 3.58 [(1.80, 7.36), p < 0.001]. Mortality rate was 2.5%.

Conclusion

SCD and its related complications constitute a significant proportion of all admissions into the adult medical ward. Approximately one in every three Ghanaian adult and adolescent SCD patients does not regularly attend the SCD clinic.

Trial Registration

The authors have confirmed clinical trial registration is not needed for this submission.

Chronic automated red cell exchange therapy for sickle cell disease

BACKGROUND

The data to support chronic automated red cell exchange (RCE) in sickle cell disease (SCD) outside of stroke prevention, is limited, especially in adults.

STUDY DESIGN AND METHODS

A retrospective analysis was conducted of patients with SCD who were referred for chronic RCE at our institution over a 10-year period. Data that were evaluated included patient demographics, referral indications, and procedural details (e.g., vascular access, adverse events, etc.). In a subanalysis, the number of annual acute care encounters during 3 years of chronic RCE was compared with that in the year preceding the first RCE.

RESULTS

A total of 164 patients were referred for chronic RCE: median age was 28 years (interquartile range [IQR] = 22-36) at referral and 60% were female. Seventy (42.6%) were naïve to chronic transfusion (simple or RCE) prior to referral. The leading indications for referral were refractory pain (73/164, 44.5%) and iron overload (57/164, 34.7%). A total of 5090 procedures occurred during the study period (median = 19, IQR = 5-45). Of the 138 patients who had central vascular access, 8 (6%) and 16 (12%) had ≥1 central-line-related thrombosis and/or infection, respectively. Of those who were not RBC alloimmunized at initiation of RCE, 12/105 (11.4%) developed new antibodies during chronic RCE. In those 30 patients who were adherent to therapy for 3 years, there was no significant difference in acute care encounters following initiation of RCE.

CONCLUSION

Prospective clinical trials are needed to determine which patients are most likely to benefit from chronic RCE and refine selection accordingly.

Predictors of hospital readmissions in adult patients with sickle cell disease

BACKGROUND

Sickle cell disease (SCD) is the most common inherited blood disorder, affecting primarily Black and Hispanic individuals. In 2016, 30-day readmissions incurred 95,445 extra days of hospitalization, $152 million in total hospitalization costs, and $609 million in total hospitalization charges.

OBJECTIVES

1) To estimate hospital readmissions within 30 days among patients with SCD in the State of California. 2) Identify the factors associated with readmission within 30 days for SCD patients in California.

METHODS

We conducted a retrospective observational study of adult SCD patients hospitalized in California between 2005 and 2014. Descriptive statistics and logistic regression models were used to examine significant differences in patient characteristics and their association with hospital readmissions.

RESULTS

From 2,728 individual index admissions, 70% presented with single admission, 10% experienced one readmission, and 20% experienced ≥ two readmissions within 30 days. Significant predictors associated with zero vs. one readmission were male gender (OR=1.37, CI: 1.06-1.77), Black ethnicity (OR=3.27, CI: 1.71-6.27) and having Medicare coverage (OR=1.89, CI: 1.30-2.75). Lower likelihood of readmission was found in those with a Charlson Comorbidity index of three or more (OR=0.53, CI: 0.29-0.97). For zero vs. ≥ two readmissions, significant predictors were male gender (OR=1.43, CI: 1.17-1.74), Black ethnicity (OR=6.90, CI: 3.41-13.97), Hispanic ethnicity (OR=2.33, CI: 1.05-5.17), Medicare coverage (OR=3.58, CI: 2.68-4.81) and Medi-Cal coverage (OR=1.70, CI: 1.31-2.20). Lower likelihood for having two or more readmissions were associated with individuals aged 65+ (OR=0.97, CI: 0.96-0.98) and those with self-payment status (OR=0.32, CI: 0.12-0.54).

CONCLUSIONS

In California, male, Black, and Hispanic patients, as well as those covered by Medicare or Medi-Cal, were found to have an increased risk of hospital readmissions. Redirecting outpatient goals to address these patient populations and risk factors is crucial for reducing readmission rates.

Global burden of transfusion in sickle cell disease

Sickle cell disease (SCD) is the most common hereditary hemoglobinopathy. The underlying pathophysiology of the red blood cell (RBC) leads to pan-systemic complications which manifest at an early age. While curative and disease-modifying treatments exist for SCD, a key intervention in the management and treatment of SCD is RBC transfusion, which can alleviate or prevent many complications. SCD patients often require chronic RBC transfusion therapy which can result in complications, such as iron overload, alloimmunization and infection. In low- and middle-income countries (LMICs), SCD patients lack appropriate access to healthcare such as newborn screening, health education, prophylaxis for infection, and treatments to reduce both mortality and SCD-related adverse effects. Poor access to RBCs for transfusion, coupled with donated blood not meeting safety standards set by the World Health Organization, presents a significant barrier for patients requiring chronic transfusions in LMICs. Unmet needs associated with blood collection, blood component processing and recipient matching all pose a serious problem in many LMICs, although this varies depending on geographic location, political organizations and economy. This review aims to provide an overview of the global burden of SCD, focusing on the availability of current treatments and the burden of chronic RBC transfusions in patients with SCD.

Age-related differences in risks and outcomes of 30-day readmission in adults with sickle cell disease

BACKGROUND

Literature on 30-day readmission in adults with sickle cell disease (SCD) is limited. This study examined the overall and age-stratified rates, risk factors, and healthcare resource utilization associated with 30-day readmission in this population.

METHODS

Using the Nationwide Readmissions Database, a retrospective cohort study was conducted to identify adult patients (aged ≥ 18) with SCD in 2016. Patients were stratified by age and followed for 30 days to assess readmission following an index discharge. The primary outcome was 30-day unplanned all-cause readmission. Secondary outcomes included index hospitalization costs and readmission outcomes (e.g., time to readmission, readmission costs, and readmission lengths of stay). Separate generalized linear mixed models estimated the adjusted odds ratios (aORs) for associations of readmission with patient and hospital characteristics, overall and by age.

RESULTS

Of 15,167 adults with SCD, 2,863 (18.9%) experienced readmission. Both the rates and odds of readmission decreased with increasing age. The SCD complications vaso-occlusive crisis and end-stage renal disease (ESRD) were significantly associated with increased likelihood of readmission (p < 0.05). Age-stratified analyses demonstrated that diagnosis of depression significantly increased risk of readmission among patients aged 18-to-29 years (aOR = 1.537, 95%CI: 1.215-1.945) but not among patients of other ages. All secondary outcomes significantly differed by age (p < 0.05).

CONCLUSION

This study demonstrates that patients with SCD are at very high risk of 30-day readmission and that younger adults and those with vaso-occlusive crisis and ESRD are among those at highest risk. Multifaceted, age-specific interventions targeting individuals with SCD on disease management are needed to prevent readmissions.

Sickle cell disease in Ontario, Canada: an epidemiologic profile based on health administrative data

BACKGROUND

The number of patients with sickle cell disease in Ontario, Canada, is unknown. In the absence of a formal registry, we performed a study to determine an approximate census via analysis of health administrative databases.

METHODS

We identified Ontario patients with a diagnosis of sickle cell disease through queries of the Discharge Abstract Database, National Ambulatory Care Reporting System and Newborn Screening Ontario database. The period of inquiry was Apr. 1, 2007, through Mar. 31, 2017. We identified repeat interactions by the same patient by cross-referencing provincial health insurance plan numbers.

RESULTS

We documented health care system interactions for 3418 unique patients (1912 [55.9%] female, median age at the time of identification 24 yr). Over the 10-year study period, patients visited the emergency department a median of 2 (interquartile range [IQR] 1-7) times and an average of 6.69 (standard deviation [SD] 26.71) times, and were admitted to hospital a median of 1 (IQR 1-5) time and an average of 4.38 (SD 8.53) times for treatment related to sickle cell disease. A total of 229 patients (6.7%) died during the study period, with an average age at death of 55 years. Even without accounting for the effects of immigration, the rate of natural increase slowed slightly over the study period owing to a decrease in the annual number of affected births.

INTERPRETATION

The estimated prevalence of patients with sickle cell disease in Ontario in 2007/08-2016/17 was 1 in 4200, and affected patients' need for hospital-based care was substantial, although highly variable. Similar queries of health administrative databases may be feasible in other Canadian provinces.

Timing matters: An analysis of the relationship between red cell transfusion timing and hospitalization outcomes in sickle cell crisis patients using the National Inpatient Sample database

Vaso-occlusive pain crisis is a debilitating complication of sickle cell disease (SCD) and it is the most common cause of hospitalization among these individuals. We studied the inpatient outcomes among patients admitted with sickle cell crisis based on the timing of red blood cell transfusion. In this retrospective study, we used the United States National Inpatient Sample (NIS) data for the year 2019, to identify adult patients hospitalized with the principal diagnosis of sickle cell crisis who received simple red blood cell transfusion during their hospitalization. Patients were divided into two groups. Those who received simple red cell transfusion within 24 hours of admission were classified as early transfusion. After adjusting for confounders, the mean adjusted length of stay for patients with early transfusion was significantly lower than those who received a late blood transfusion by 3.51 days (p-value < 0.001) along with a decrease in mean adjusted hospitalization charges and cost, by 25,487 and 4,505 United States Dollar (USD) respectively. The early red cell transfusion was also associated with a decrease in inpatient mortality, demonstrated by an adjusted odds ratio (aOR) of 0.19 (p-value 0.036), and a reduction in in-hospital sepsis, with an aOR of 0.28 (p-value < 0.001), however, no statistically significant difference was found between the two groups regarding acute respiratory failure requiring intubation, vasopressors requirement, acute kidney injury requiring dialysis and intensive care unit (ICU) admission. We recommend timely triage and reassessment to identify sickle cell crisis patients requiring blood transfusion. This intervention can notably affect the inpatient length of stay, resource utilization, and hospitalization outcomes.

Acute chest syndrome in adult patients with sickle cell disease: The relationship with the time to onset after hospital admission

Data on acute chest syndrome (ACS) in adult sickle cell disease patients are scarce. In this study, we describe 105 consecutive ACS episodes in 81 adult patients during a 32-month period and compare the characteristics as a function of the time to onset after hospital admission for a vaso-occlusive crisis (VOC), that is early-onset episodes (time to onset ≤24 h, 42%) versus secondary episodes (>24 h, 58%; median [interquartile range] time to onset: 2 [2-3] days). The median age was 27 [22-34] years, 89% of the patients had an S/S or S/β⁰ -thalassaemia genotype; 81% of the patients had a history of ACS (median: 3 [2-5] per patient), only 61% were taking a disease-modifying treatment at the time of the ACS. Fever and chest pain were noted in respectively 54% and 73% of the episodes. Crackles (64%) and bronchial breathing (32%) were the main abnormal auscultatory findings. A positive microbiological test was found for 20% of episodes. Fifty percent of the episodes required a blood transfusion; ICU transfer and mortality rates were respectively 29% and 1%. Secondary and early-onset forms of ACS did not differ significantly. Disease-modifying treatments should be revaluated after each ACS episode because the recurrence rate is high.

[Acute chest syndrome in adult sickle cell patients]

Sickle cell disease is a frequent genetic condition, due to a mutation of the β-globin gene, leading to the production of an abnormal S hemoglobin and characterized by multiple vaso-occlusive events. The acute chest syndrome is a severe complication associated with a significant disability and mortality. It is defined by the association of one or more clinical respiratory manifestations and a new infiltrate on lung imaging. Its pathophysiology is complex and implies vaso-occlusive phenomena (pulmonary vascular thrombosis, fat embolism), infection, and alveolar hypoventilation. S/S or S/β⁰-thalassemia genotype, a history of vaso-occlusive crisis or acute chest syndrome, a low F hemoglobin level (<5%), a high steady-state hemoglobin level (> 10 g/dL), or a high steady-state leukocytosis (>10 G/L) are the main risk factors. Febrile chest pain, dyspnea, sometimes cough with expectorations are its main clinical manifestations, and bi-basal crackles are found at auscultation. Inferior alveolar opacities with or without pleural effusions are identified on chest X-ray or CT-scan. Management of the acute chest syndrome should be prompt and implies, besides the recognition of severity signs, a multimodal analgesia, oxygen supplementation, sometimes a parenteral antibiotic treatment and the frequent use of blood transfusions especially in the most severe cases. Prevention is important and includes a regular monitoring of hospitalized patients and the use of incentive spirometry.

Burden of central nervous system complications in sickle cell disease: A systematic review and meta-analysis

Sickle cell disease (SCD) patients are at high risk of central nervous system (CNS) complications and may experience significant morbidity. The study was conducted to describe the comprehensive burden of SCD-related CNS complications and to identify patient-reported outcome (PRO) instruments for future research. The review included 32 studies published from January 2000 to 2020, evaluating humanistic and economic outcomes. Twenty-three studies reported humanistic outcomes, 16 of which measured cognitive function using Wechsler Intelligence Scales. A meta-analysis was conducted, finding full-scale intelligence quotient (IQ) was significantly lower in: overt stroke versus controls: -12.6 (p < .001); silent cerebral infarct (SCI) versus controls: -5.7 (p < .001); overt stroke versus SCI: -9.4 (p = .008); and any event versus controls: -7.6 (p < .001). This review quantified the cognitive deficits associated with CNS complications in pediatric SCD populations and highlights the need for improved prevention/treatment. As PRO evidence was limited, we discussed areas for future research.

Comparing the Effectiveness of Education Versus Digital Cognitive Behavioral Therapy for Adults With Sickle Cell Disease: Protocol for the Cognitive Behavioral Therapy and Real-time Pain Management Intervention for Sickle Cell via Mobile Applications (CaRISMA) Study

Background

Patients with sickle cell disease (SCD) experience significant medical and psychological stressors that affect their mental health, well-being, and disease outcomes. Digital cognitive behavioral therapy (CBT) has been used in other patient populations and has demonstrated clinical benefits. Although evidence-based, nonpharmacological interventions for pain management are widely used in other populations, these treatments have not been well studied in SCD. Currently, there are no adequately powered large-scale clinical trials to evaluate the effectiveness and dissemination potential of behavioral pain management for adults with SCD. Furthermore, some important details regarding behavioral therapies in SCD remain unclear—in particular, what works best for whom and when.

Objective

Our primary goal is to compare the effectiveness of two smartphone–delivered programs for reducing SCD pain symptoms: digital CBT versus pain and SCD education (Education). Our secondary goal is to assess whether baseline depression symptoms moderate the effect of interventions on pain outcomes. We hypothesize that digital CBT will confer greater benefits on pain outcomes and depressive symptoms at 6 months and a greater reduction in health care use (eg, opioid prescriptions or refills or acute care visits) over 12 months.

Methods

The CaRISMA (Cognitive Behavioral Therapy and Real-time Pain Management Intervention for Sickle Cell via Mobile Applications) study is a multisite comparative effectiveness trial funded by the Patient-Centered Outcomes Research Institute. CaRISMA is conducted at six clinical academic sites, in partnership with four community-based organizations. CaRISMA will evaluate the effectiveness of two 12-week health coach–supported digital health programs with a total of 350 participants in two groups: CBT (n=175) and Education (n=175). Participants will complete a series of questionnaires at baseline and at 3, 6, and 12 months. The primary outcome will be the change in pain interference between the study arms. We will also evaluate changes in pain intensity, depressive symptoms, other patient-reported outcomes, and health care use as secondary outcomes. We have 80% power to detect a difference of 0.37 SDs between study arms on 6-month changes in the outcomes with 15% expected attrition at 6 months. An exploratory analysis will examine whether baseline depression symptoms moderate the effect of the intervention on pain interference.

Results

This study will be conducted from March 2021 through February 2022, with results expected to be available in February 2023.

Conclusions

Patients with SCD experience significant disease burden, psychosocial stress, and impairment of their quality of life. CaRISMA proposes to leverage digital technology and overcome barriers to the routine use of behavioral treatments for pain and depressive symptoms in the treatment of adults with SCD. The study will provide data on the comparative effectiveness of digital CBT and Education approaches and evaluate the potential for implementing evidence-based behavioral interventions to manage SCD pain.

Trial Registration

ClinicalTrials.gov NCT04419168; https://clinicaltrials.gov/ct2/show/NCT04419168.

International Registered Report Identifier (IRRID)

PRR1-10.2196/29014

Machine-learning algorithms for predicting hospital re-admissions in sickle cell disease

Reducing preventable hospital re-admissions in Sickle Cell Disease (SCD) could potentially improve outcomes and decrease healthcare costs. In a retrospective study of electronic health records, we hypothesized Machine-Learning (ML) algorithms may outperform standard re-admission scoring systems (LACE and HOSPITAL indices). Participants (n = 446) included patients with SCD with at least one unplanned inpatient encounter between January 1, 2013, and November 1, 2018. Patients were randomly partitioned into training and testing groups. Unplanned hospital admissions (n = 3299) were stratified to training and testing samples. Potential predictors (n = 486), measured from the last unplanned inpatient discharge to the current unplanned inpatient visit, were obtained via both data-driven methods and clinical knowledge. Three standard ML algorithms, Logistic Regression (LR), Support-Vector Machine (SVM), and Random Forest (RF) were applied. Prediction performance was assessed using the C-statistic, sensitivity, and specificity. In addition, we reported the most important predictors in our best models. In this dataset, ML algorithms outperformed LACE [C-statistic 0·6, 95% Confidence Interval (CI) 0·57-0·64] and HOSPITAL (C-statistic 0·69, 95% CI 0·66-0·72), with the RF (C-statistic 0·77, 95% CI 0·73-0·79) and LR (C-statistic 0·77, 95% CI 0·73-0·8) performing the best. ML algorithms can be powerful tools in predicting re-admission in high-risk patient groups.

Transfusion support in patients with sickle cell disease

Blood transfusions are an integral component of the management of acute and chronic complications of sickle cell disease. Red cells can be administered as a simple transfusion, part of a modified exchange procedure involving manual removal of autologous red cells and infusion of donor red cells, and part of an automated red cell exchange procedure using apheresis techniques. Individuals with sickle cell disease are at risk of multiple complications of blood transfusions, including transfusional hemosiderosis, auto- and alloimmunization to minor red cell and human leukocyte antigens, delayed hemolytic transfusion reactions, and hyper-hemolysis. In low- and middle-income countries in sub-Saharan Africa, where a directed donor system is prevalent and limited laboratory methods are in place to perform extended red cell phenotyping, leukodepletion of cellular products, and infectious disease screening, there are additional challenges to providing safe and adequate transfusion support for this patient population. We review current indications for acute and chronic transfusions in sickle cell disease that are derived primarily from randomized controlled trials and observational studies in children living in high-income countries. We will highlight populations with unique transfusion needs, such as pregnant women and children, as well as the role of the transfusion medicine consultative service for individuals with sickle cell disease planning to have curative hematopoietic stem cell transplantation or gene therapy. Finally, we will discuss risk factors for alloimmunization in individuals with sickle cell disease, emerging new strategies to prevent alloimmunization in this population, and critical gaps in the implementation of transfusion guidelines for sickle cell disease in high- and low-income countries.

Transfusion support: Considerations in pediatric populations

Over 400,000 units of blood and blood products are transfused to pediatric patients annually, yet only sparse high-quality data exist to guide the preparation and administration of blood products in this population. The direct application of data from studies in adult patients should be undertaken with caution, as there are dissimilarities in the pathology and physiology between adult and pediatric patients. We provide an overview of available evidence in the field of pediatric transfusion medicine, summarizing indications for blood product transfusion, thresholds for transfusion and indications for blood product modifications.

The controversial role of red cell transfusions for sickle cell pain

PURPOSE OF REVIEW

Red cell transfusions are one of the most common and important therapies used for patients with sickle cell disease (SCD). For prevention of strokes, there is abundant evidence that transfusions are efficacious, whereas for other indications, such as prevention of pain, there are less data. Nonetheless, with few therapeutic options, the use of transfusion for prevention of acute pain has increased in children and adults with SCD without a clear understanding of its benefits.

RECENT FINDINGS

Although it makes conceptual sense that red cell transfusions would prevent pain that arises from vaso-occlusion, we now know that the mechanism of pain is more complex than vaso-occlusion alone. Recent taxonomies recognize a chronic pain syndrome that is both common in adults with SCD and affects the presentation of acute pain. It is not known if acute pain on the background of chronic pain responds differently to sickle cell therapies, such as hydroxyurea and blood transfusion.

SUMMARY

In this review, we will examine the studies that have investigated whether red cell transfusions are efficacious for preventing pain. In the absence of high-quality data that specifically addresses this question, we will outline our approach, which might soon change with new drugs and curative therapies on the horizon.

Hospital Readmission of Adolescents and Young Adults With Complex Chronic Disease

IMPORTANCE

Adolescents and young adults (AYA) who have complex chronic disease (CCD) are a growing population that requires hospitalization to treat severe, acute health problems. These patients may have increased risk of readmission as demands on their self-management increase and as they transfer care from pediatric to adult health care practitioners.

OBJECTIVE

To assess variation across CCDs in the likelihood of readmission for AYA with increasing age.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective 1-year cross-sectional study of the 2014 Agency for Healthcare Research and Quality Nationwide Readmissions Database for all US hospitals. Participants were 215 580 hospitalized individuals aged 15 to 30 years with cystic fibrosis (n = 15 213), type 1 diabetes (n = 86 853), inflammatory bowel disease (n = 48 073), spina bifida (n = 7819), and sickle cell anemia (n = 57 622) from January 1, 2014, to December 1, 2014.

EXPOSURES

Increasing age at index admission.

MAIN OUTCOMES AND MEASURES

Unplanned 30-day hospital readmission. Readmission odds were compared by patients' ages in 2-year epochs (with age 15-16 years as the reference) using logistic regression, accounting for confounding patient characteristics and data clustering by hospital.

RESULTS

Of 215 580 participants, 115 982 (53.8%) were female; the median (interquartile range) age was 24 (20-27) years. Across CCDs, multimorbidity was common; the percentages of index hospitalizations with 4 or more coexisting conditions ranged from to 33.4% for inflammatory bowel disease to 74.2% for spina bifida. Thirty-day hospital readmission rates varied significantly across CCDs: 20.2% (cystic fibrosis), 19.8% (inflammatory bowel disease), 20.4% (spina bifida), 22.5% (type 1 diabetes), and 34.6% (sickle cell anemia). As age increased from 15 to 30 years, unadjusted, 30-day, unplanned hospital readmission rates increased significantly for all 5 CCD cohorts. In multivariable analysis, age trends in the adjusted odds of readmission varied across CCDs. For example, for AYA who had cystic fibrosis, the adjusted odds of readmission increased to 1.9 (95% CI, 1.5-2.3) by age 21 years and remained elevated through age 30 years. For AYA who had type 1 diabetes, the adjusted odds of readmission peaked at ages 23 to 24 years (odds ratio, 2.3; 95% CI, 2.1-2.6) and then declined through age 30 years.

CONCLUSIONS AND RELEVANCE

These findings suggest that hospitalized AYA who have CCDs have high rates of multimorbidity and 30-day readmission. The adjusted odds of readmission for AYA varied significantly across CCDs with increasing age. Further attention is needed to hospital discharge care, self-management, and prevention of readmission in AYA with CCD.

Red blood cell exchange in patients with sickle cell disease-indications and management: a review and consensus report by the therapeutic apheresis subsection of the AABB

BACKGROUND

A prior practice survey revealed variations in the management of patients with sickle cell disease (SCD) and stressed the need for comprehensive guidelines. Here we discuss: 1) common indications for red blood cell exchange (RCE), 2) options for access, 3) how to prepare the red blood cells (RBCs) to be used for RCE, 4) target hemoglobin (Hb) and/or hematocrit (Hct) and HbS level, 5) RBC depletion/RCE, and 6) some complications that may ensue.

STUDY DESIGN AND METHODS

Fifteen physicians actively practicing apheresis from 14 institutions representing different areas within the United States discussed how they manage RCE for patients with SCD.

RESULTS

Simple transfusion is recommended to treat symptomatic anemia with Hb level of less than 9 g/dL. RCE is indicated to prevent or treat complications arising from the presence of HbS. The most important goals are reduction of HbS while also preventing hyperviscosity. The usual goals are a target HbS level of not more than 30% and Hct level of less than 30%.

CONCLUSION

Although a consensus as to protocol details may not be possible, there are areas of agreement in the management of these patients, for example, that it is optimal to avoid hyperviscosity and iron overload, that a target Hb S level in the range of 30% is generally desirable, and that RCE as an acute treatment for pain crisis in the absence of other acute or chronic conditions is ordinarily discouraged.

Sensitization of C-fiber nociceptors in mice with sickle cell disease is decreased by local inhibition of anandamide hydrolysis

Chronic pain and hyperalgesia, as well as pain resulting from episodes of vaso-occlusion, are characteristic features of sickle cell disease (SCD) and are difficult to treat. Since there is growing evidence that increasing local levels of endocannabinoids can decrease hyperalgesia, we examined the effects of URB597, a fatty acid amide hydrolase (FAAH) inhibitor, which blocks the hydrolysis of the endogenous cannabinoid anandamide, on hyperalgesia and sensitization of cutaneous nociceptors in a humanized mouse model of SCD. Using homozygous HbSS-BERK sickle mice, we determined the effects of URB597 on mechanical hyperalgesia and on sensitization of C-fiber nociceptors in vivo. Intraplantar administration of URB597 (10 μg in 10 μL) decreased the frequency of withdrawal responses evoked by a von Frey monofilament (3.9 mN bending force) applied to the plantar hind paw. This was blocked by the CB1 receptor antagonist AM281 but not by the CB2 receptor antagonist AM630. Also, URB597 decreased hyperalgesia in HbSS-BERK/CB2R sickle mice, further confirming the role of CB1 receptors in the effects produced by URB597. Electrophysiological recordings were made from primary afferent fibers of the tibial nerve in anesthetized mice. The proportion of Aδ- and C-fiber nociceptors that exhibited spontaneous activity and responses of C-fibers to mechanical and thermal stimuli were greater in HbSS-BERK sickle mice as compared to control HbAA-BERK mice. Spontaneous activity and evoked responses of nociceptors were decreased by URB597 via CB1 receptors. It is suggested that enhanced endocannabinoid activity in the periphery may be beneficial in alleviating chronic pain associated with SCD.

Are Readmissions After THA Preventable?

BACKGROUND

Readmissions after total joint arthroplasty have become a key quality measure in elective surgery in the United States. The Affordable Care Act includes the Hospital Readmission Reduction Program, which calls for reduced payments to hospitals with excessive readmissions. This policy uses a method to determine excess readmission ratios and calculate readmission payment adjustments to hospitals, however, it is unclear whether readmission rates are an effective quality metric. The reasons or conditions associated with readmission after elective THA have been well established but the extent to which readmissions can be prevented after THA remains unclear.

QUESTIONS/PURPOSES

(1) Are unplanned readmissions after THA associated with orthopaedic or medical causes? (2) Are these readmissions preventable? (3) When during the course of aftercare are orthopaedic versus medical readmissions more likely to occur?

METHODS

We retrospectively evaluated all 1096 elective THAs for osteoarthritis performed between January 1, 2011 and June 30, 2014 at a major academic medical center. Of those, 69 patients (6%) who met inclusion criteria were readmitted in our healthcare system within 90 days of discharge after the index procedure during the study period. Fifty patients were readmitted within 30 days of discharge after the index procedure (5%). We defined a readmission as any unplanned inpatient or observation status admission to the hospital spanning at least one midnight. A panel of physicians not involved in the care of these patients used available criteria and existing consensus guidelines to evaluate the medical records, radiographs, and operative reports to identify whether the underlying reason for readmission was orthopaedic versus medical. They subsequently were classified as either nonpreventable or potentially preventable readmissions, based on any care that may have occurred during the index hospitalization. To make such determinations, consensus specialty society guidelines were used whenever possible for each readmission diagnosis.

RESULTS

A total of 50 of 1096 patients (5% of those who underwent THA during the period in question) were readmitted within 30 days and 69 of 1096 (6%) were readmitted within 90 days of their index procedures. Thirty-one patients were readmitted for orthopaedic reasons (31/69; 45%) and 38 of 69 were readmitted for medical reasons (55%). Three readmissions (three of 69; 4%) were identified as potentially preventable. Of these potentially preventable readmissions, one was orthopaedic (hip dislocation) and two were medical. Thirty-day readmissions were more likely to be orthopaedic than 90-day readmissions (odds ratio, 4.06; 95% CI, 1.18-13.96; p = 0.026).

CONCLUSIONS

Using a panel of expert reviewers, available existing criteria, and consensus methodology, it appears only a small percentage of readmissions after THA are potentially preventable. Orthopaedic readmissions occur earlier during the postoperative course. Currently, existing policies and readmission penalties may not serve as valuable external quality metrics. The readmission rates in our study may represent the threshold for expected readmission rates after THA. Future studies should enroll larger numbers of patients and have independent review panels in efforts to refine criteria for what constitutes preventable readmissions.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Sickle cell disease: when and how to transfuse

Blood transfusion remains an important therapeutic intervention in patients with sickle cell disease (SCD), aiming to both increase the oxygen carrying capacity of blood and to reduce the complications of vaso-occlusion. Simple, manual exchange and automated exchange can be effective in reducing the acute and chronic complications of SCD, and the advantages and disadvantages of each methodology mean they all have a role in different situations. Evidence for the role of emergency transfusion in the management of the acute complications of SCD, including acute pain and acute chest syndrome, comes from observational data. Several important randomized controlled trials have shown the efficacy of transfusion in primary and secondary stroke prevention in patients with SCD but, outside these areas, clinical practice lacks a clear evidence base. Evidence for the role of long-term transfusion in the prevention of the non-neurologic chronic complications of SCD comes from analysis of secondary outcomes of these randomized trials and from observational data. In view of the paucity of data, the risks and benefits of transfusion should be fully discussed with patients/families before a long-term transfusion program is commenced. Evidence is only available for the role of preoperative transfusion or for prophylactic transfusion through pregnancy in certain situations, and the role of transfusions outside these situations is discussed. Questions about when and how to transfuse in SCD remain and will need further randomized trials to provide answers.

Renal Failure in Sickle Cell Disease: Prevalence, Predictors of Disease, Mortality and Effect on Length of Hospital Stay

Renal dysfunction in sickle cell disease is not only a chronic comorbidity but also a mortality risk factor. Though renal dysfunction starts early in life in sickle cell patients, the predictors that can identify sickle cell disease patients at risk of developing renal dysfunction is not known. We used the Truven Health MarketScan^® Medicaid Databases from 2007 to 2012. Incidence of new acute renal failure (ARF) and chronic kidney disease (CKD) was calculated in this cohort. There were 9481 patients with a diagnosis of sickle cell disease accounting for 64,201 hospital admissions, during the study period. Both ARF and CKD were associated with higher risk of inpatient mortality, longer duration of the hospital stay and expensive hospitalizations. The yearly incidence of new ARF in sickle cell disease patients was 1.4% and annual CKD incidence was 1.3%. The annual rate of new ARF and CKD in the control group was 0.4 and 0.6%, respectively. The most important predictors of new CKD were proteinuria, ARF and hypertension. Chronic kidney disease, hypertension and sickle cell crisis were the most important predictors of new ARF. The annual rate of incidences of ARF and CKD were 2- to 3-fold higher in sickle cell disease compared to the non sickle cell disease group. Besides the common risk factors for renal disease in the general population, it is imperative to monitor the sickle cell disease patients with more severe disease to prevent them from developing renal dysfunction.