Oral estrogens decrease bleeding time and improve clinical bleeding in patients with renal failure

Transdermal estradiol for the management of refractory uremic bleeding

PURPOSE

The efficacy and thrombogenicity of transdermal estradiol in the management of refractory uremic bleeding in adults are examined.

SUMMARY

Platelet dysfunction from chronic kidney disease may induce uremic bleeding. This type of bleeding may involve the skin, oral and nasal mucosa, gingivae, respiratory system, and gastrointestinal or urinary tract. While the mainstay of treatment for uremic bleeding primarily involves dialysis and use of prohemostatic agents such as desmopressin and erythropoiesis-stimulating agents, certain patients may experience bleeding refractory to these interventions. In this clinical scenario, a weak conditional recommendation (grade 2C) supporting transdermal estradiol as a therapy of last resort exists. Limited data suggest that transdermal estradiol may reduce bleeding time and transfusion requirements in dialysis patients with recurrent episodes of hematochezia, gastrointestinal telangiectasia, and hematomas. The management of uremic bleeding will require long-term therapy, and case reports have documented the safe use of transdermal estradiol for up to 25 months. Oral conjugated estrogens increase the risk of deep vein thrombosis in women; however, the transdermal route of administration has been associated with a lower incidence of venous thromboembolism and stroke relative to oral estrogen and, in some studies, its associated risk of thrombosis is not significantly different when compared with placebo.

CONCLUSION

Patients who are refractory to routine interventions for uremic bleeding may benefit from transdermal estrogen despite the limited data. Extended therapy with low-dose transdermal estrogen (≤50 μg daily) may provide a hemostatic benefit that outweighs thrombotic risk.

Hemostatic Agents in Critically Ill Patients

How to cite this article: Das SK, Reddy MM, Ray S. Hemostatic Agents in Critically Ill Patients. Indian J Crit Care Med 2019;23(Suppl 3):S226–S229.

Diagnostic and therapeutic considerations for obscure gastrointestinal bleeding in patients with chronic kidney disease

Recurrent obscure gastrointestinal bleeding amongst patients with chronic kidney disease is a challenging problem gastroenterologists are facing and is associated with an extensive diagnostic workup, limited therapeutic options, and high healthcare costs. Small-bowel angiodysplasia is the most common etiology of obscure and recurrent gastrointestinal bleeding in the general population. Chronic kidney disease is associated with a higher risk of gastrointestinal bleeding and of developing angiodysplasia compared with the general population. As a result, recurrent bleeding in this subgroup of patients is more prevalent and is associated with an increased number of endoscopic and radiographic procedures with uncertain benefit. Alternative medical therapies can reduce re-bleeding; however, more studies are needed to confirm their efficacy in this subgroup of patients.

Use of Conjugated Estrogens in Life-Threatening Gastrointestinal Bleeding in Hemodialysis Patients—A Review

Hormonal agents (estrogen and progesterone) are being studied for their use in bleeding. This observance was initially explored in a patient with hereditary hemorrhagic telangiectasia (HHT) with epistaxis had variation in bleeding depending on her menstrual cycles.1 Thus, hormonal therapy was initially used in patients with HHT to control episodes of epistaxis.2 The literature on hormonal therapy in patients with life-threatening bleeding from gastrointestinal (GI) lesions is very limited. There are a few clinical trials in patients with chronic bleeds. However, no definite guidelines exist on their use in life-threatening GI bleeding in patients with uremia. Here, we describe a case with a life-threatening GI bleeding requiring multiple endoscopies and intensive care unit stay that responded to conjugated estrogens. We have done extensive research on English medical literature on PubMed and Google Scholar on the use of hormonal therapy for GI bleeding in patients with renal failure, and here we present the data as a review.

Bleeding and thrombotic complications of kidney disease

With the rising prevalence of kidney disease, clinicians are increasingly faced with concerns about potential thrombotic and bleeding complications. Thrombotic risk, both arterial and venous, predominates with all severities of kidney disease but bleeding manifestations become an additional concern particularly with uraemia. This article reviews these contrasting problems and discusses strategies for prevention and management in the context of renal impairment, renal replacement therapy and renal transplantation.

Adverse drug events associated with disorders of coagulation

Disorders of coagulation are common adverse drug events encountered in critically ill patients and present a serious concern for intensive care unit (ICU) clinicians. Dosing strategies for medications used in the ICU are typically developed for use in noncritically ill patients and, therefore, do not account for the altered pharmacokinetic and pharmacodynamic properties encountered in the critically ill as well as the increased potential for drug-drug interactions, given the far greater number of medications ordered. This substantially increases the risk for coagulation-related adverse reactions, such as a bleeding or prothrombotic events. Although many medications used in the ICU have the potential to cause coagulation disorders, the exact incidence will vary based on the specific medication, dose, concomitant drug therapy, ICU setting, and patient-specific comorbidities. Clinicians must strongly consider these factors when evaluating the risk/benefit ratio for a particular therapy. This review surveys recent literature documenting the risk for adverse drug reactions specific to bleeding and/or clotting with commonly used medications in the ICU.

Evidence-based treatment recommendations for uremic bleeding

Uremic bleeding syndrome is a recognized consequence of renal failure and can result in clinically significant sequelae. Although the pathophysiology of the condition has yet to be fully elucidated, it is believed to be multifactorial. This article is a review of both the normal hemostatic and homeostatic mechanisms that operate within the body to prevent unnecessary bleeding, as well as an in-depth discussion of the dysfunctional components that contribute to the complications associated with uremic bleeding syndrome. As a result of the multifactorial nature of this syndrome, prevention and treatment options can include one or a combination of the following: dialysis, erythropoietin, cryoprecipitate, desmopressin, and conjugated estrogens. Here, these treatment options are compared with regard to their mechanism of action, and onset and duration of efficacy. An extensive review of the clinical trials that have evaluated each treatment is also presented. Lastly, we have created an evidence-based treatment algorithm to help guide clinicians through most clinical scenarios, and answered common questions related to the management of uremic bleeding.

Perioperative systemic haemostatic agents

Skilful surgery combined with blood-saving methods and careful management of blood coagulation will all help reduce unnecessary blood loss and transfusion requirements. Excessive surgical bleeding causes hypovolaemia, haemodynamic instability, anaemia and reduced oxygen delivery to tissues, with a subsequent increase in postoperative morbidity and mortality. The role of anaesthetists in managing surgical blood loss has increased greatly in the last decade. Position of the patient during surgery and the provision of a hypotensive anaesthetic regimen were once considered the most important contributions of the anaesthetist to decreasing blood loss. Now, several pharmacological haemostatic agents are being used by anaesthetists as blood-saving agents. After a brief discussion of the physiology of haemostasis, this article will review the evidence for the role of such agents in reducing perioperative blood loss and transfusion requirements.

Perioperative management of patients with chronic kidney disease or ESRD

The perioperative management of patients with chronic kidney disease (CKD) or dialysis-dependent end-stage renal disease (ESRD) is complicated by both the underlying renal dysfunction, with associated disturbances of fluid and electrolyte homeostasis and altered drug clearance, and the presence of associated co-morbid conditions, including diabetes mellitus, chronic hypertension and cardiovascular and cerebrovascular disease. The impact of CKD on fluid and electrolyte management, haematological and cardiovascular complications and drug management in the perioperative period are reviewed. Special issues related to the management of haemodialysis and peritoneal dialysis patients in the perioperative period are also reviewed.

17beta-estradiol corrects hemostasis in uremic rats by limiting vascular expression of nitric oxide synthases

Conjugated estrogens shorten the prolonged bleeding time in uremic patients and are similarly effective in a rat model of uremia. We have previously demonstrated that the shortening effect of a conjugated estrogen mixture or 17beta-estradiol on bleeding time was abolished by the nitric oxide (NO) precursor L-arginine, suggesting that the effect of these drugs on hemostasis in uremia might be mediated by changes in the NO synthetic pathway. The present study investigated the biochemical mechanism(s) by which conjugated estrogens limit the excessive formation of NO. 17beta-estradiol (0.6 mg/kg), given to rats made uremic by reduction of renal mass, significantly reduced bleeding time within 24 h and completely normalized plasma concentrations of the NO metabolites, nitrites and nitrates, and of NO synthase (NOS) catalytic activity, determined by NADPH-diaphorase staining in the thoracic aorta. Endothelial NOS (ecNOS) and inducible NOS (iNOS) immunoperoxidase staining in the endothelium of uremic aortas of untreated rats was significantly more intense than in control rats, while in uremic rats receiving 17beta-estradiol staining was comparable to controls. Thus 17beta-estradiol corrected the prolonged bleeding time of uremic rats and fully normalized the formation of NO by reducing the expression of ecNOS and iNOS in vascular endothelium. These results provide a possible biochemical explanation of the well-known effect of estrogens on primary hemostasis in uremia, in experimental animals and humans.

Renal biopsy in high-risk patients with medical diseases of the kidney

The number of high-risk patients undergoing renal biopsy is likely to increase in the near future because of the increased use of anticoagulants for such conditions as atrial fibrillation, combined liver and kidney disease caused by hepatitis C, and the aging of the population. Nephrologists need to become increasingly familiar with evaluating such patients through both specialized management of percutaneous kidney biopsy and alternate methods of renal biopsy, which primarily consist of open (surgical) biopsy, transjugular (transvenous) biopsy, and laparoscopic biopsy. The indications, complications, and general approach to such patients are discussed. This is a US government work. There are no restrictions on its use.

Uremic bleeding: pathogenesis and therapy

BACKGROUND

We reviewed current understanding of the pathophysiology of the uremic bleeding diathesis and discuss accepted therapeutic interventions that minimize the risk of bleeding in the uremic patient.

METHODS

Computerized literature searches and references from previous publications, including articles describing original research and reviews pertaining to the pathophysiology of and clinical approach to uremic bleeding.

RESULTS

The most common hemorrhagic manifestations in uremia are prolonged bleeding from puncture sites; nasal, gastrointestinal and genitourinary bleeding; and subdural hematomas. The most useful clinical laboratory test to assess both bleeding risk and response to therapy is bleeding time. It correlates better with clinical bleeding complications than indices of azotemia (eg, blood urea nitrogen [BUN], creatinine) or in vitro platelet aggregation tests. A low hematocrit is also correlated with increased bleeding risk. Anemia plays an important role in the bleeding diathesis of uremia and its correction with red cell transfusions or human recombinant erythropoietin is critical. Anticoagulation during hemodialysis may transiently exacerbate the bleeding diathesis. Hemodialysis and peritoneal dialysis improve the hemostatic defect and renal transplantation totally corrects it. Cryoprecipitate has been largely replaced by desmopressin acetate, which acts promptly (in less than 1 hour) but has a short duration of action (hours) and exhibits tachyphylaxis. Conjugated estrogens are slower in the onset of action (about 6 hours) but their effect lasts for about 2 weeks.

CONCLUSIONS

The pathophysiology of the bleeding diathesis of uremia is complex and incompletely understood but useful clinical tests and therapies have evolved empirically. Broadly available dialysis and the advent of erythropoietin are likely to reduce the magnitude of this problem.

Use of intravenous Premarin to decrease postoperative blood loss after pediatric scoliosis surgery

STUDY DESIGN

The hemostatic effect of conjugated estrogens (Premarin, Wyeth-Ayerst Laboratories, Philadelphia, PA) has been reported in the literature, but no study has investigated its effectiveness in decreasing blood loss in pediatric spinal procedures.

OBJECTIVE

To determine the effectiveness of intravenously administered Premarin in the immediate postoperative period in decreasing Hemovac drainage postoperatively.

METHODS

Sixty-four adolescent patients undergoing spinal surgery, both posterior and anterior/posterior procedures, were studied. Thirty-two patients served as control subjects. The other 32 received Premarin, 1 mg/kg intravenously in the immediate postoperative period. Hemovac drainage was measured during a period of 48 hours.

RESULTS

In measuring Hemovac drainage for 48 hours in both groups, there was a 37% decrease in the volume of the postoperative drainage (mL/kg) in the patients receiving Premarin postoperatively. Measurement of adjusted volumes (mL/kg) revealed a statistically significant decrease in postoperative bleeding after administration of Premarin.

CONCLUSIONS

Administration of Premarin resulted in a 37% decrease in the volume of postoperative drainage (mL/kg) without complications. Premarin appears to be effective in decreasing postoperative blood loss in a pediatric postoperative spinal population.

Beneficial effect of low-dose transdermal estrogen on bleeding time and clinical bleeding in uremia

Patients with renal failure frequently manifest a hemorrhagic diathesis characterized by prolonged bleeding time (BT). Oral and intravenous estrogens have been shown to correct this abnormality, but both estrogens have real and potential disadvantages, especially for long-term use. We examined the effectiveness of transdermally applied 17 beta-estradiol on clinical bleeding and BT in renal failure patients. Six patients with renal insufficiency and prolonged BT were included in the study. Four patients had recurring gastrointestinal bleeding from telangiectasias. Two patients anticipated percutaneous renal biopsy. Transdermal estradiol 50 or 100 micrograms/24 hr was applied every 3.5 days for a period of 2 months. Bleeding times were measured just prior to estrogen administration (pre-estradiol) and again on cessation of clinical bleeding or prior to renal biopsy (post-estradiol). Differences were analyzed using a paired t-test. Erythrocyte transfusion requirement 2 months before and 2 months after estradiol application also was observed. Hemorrhage in all four actively bleeding patients ceased or improved, as reflected by the reduced need for transfusion. Bleeding time improved significantly (P = 0.008) when comparing before (day 0) with after (days 1 to 17) estradiol application. No adverse reactions associated with estradiol occurred over 2 months of therapy. In conclusion, transdermal application of 17 beta-estradiol is a safe and effective means to reduce BT and clinical hemorrhage in patients with renal failure and prolonged BT.

Influence of hormones on platelet intracellular calcium

The pathophysiology of thromboembolic disease associated with estrogen therapy is poorly understood. There are innumerable calcium-dependent activities involved in platelet function. To determine whether platelet calcium levels are affected by exogenous hormones, intracellular calcium and release were studied in platelets in various hormonal environments and findings were correlated with platelet adhesion and aggregation. Platelet intracellular calcium concentration and release was significantly decreased in women ingesting tamoxifen compared to controls and significantly increased, as was platelet adhesion, in oral contraceptive users. Platelets incubated ex vivo with estradiol had increased intracellular calcium and release but there was decreased adhesion to fibronectin. Intracellular calcium concentration and release were not affected when platelets were incubated with tamoxifen. Adhesion to collagen III was increased in tamoxifen-incubated platelets. Only oral contraceptive users had increased sensitivity to aggregating agents. This data suggests that 17 beta estradiol, progesterone, and tamoxifen likely have a nongenomic effect on platelet intracellular calcium and calcium release and that platelet calcium levels are closely related to the degree of platelet adhesion and aggregation in vivo.

Paradoxical influence of estrogenic hormones on platelet-endothelial cell interactions

Controversies abound in the literature about the safety and efficacy of tamoxifen and estrogen. We studied the effect of these 2 hormonal agents on factors involved in in vitro thrombogenesis: platelets and endothelial cells. Endothelial cells were derived from human umbilical veins and platelets were obtained from premenopausal and postmenopausal women, women on oral contraceptives, postmenopausal women on hormone replacement therapy, men, and patients with breast cancer who had been taking adjuvant tamoxifen for more than 1 year. The interaction of platelets with endothelial cell matrix was measured in 2 systems: 1) in a flow chamber at low shear rate and, 2) with 51Cr labeled platelets in a "static" culture system. In the static system, platelets from women on tamoxifen exhibited decreased platelet adherence to endothelial cell matrix whether they were grown in tamoxifen or control conditions, when compared to platelets from premenopausal women. When flow (25 sec-1) was added these differences were negated. Neither tamoxifen nor 17 beta estradiol had an effect on endothelial cell proliferation or platelet aggregation. Adhesion of platelets at low shear was not altered when platelet rich plasma was incubated with tamoxifen nor when endothelial cells were grown in tamoxifen. In contrast, incubation of platelets in 17 beta estradiol decreased platelet adhesion at low shear rate, however, there was no effect on platelet adhesion when endothelial cells were grown in 17 beta estradiol. We conclude that in early stages of thrombus formation as measured in vitro, tamoxifen may not have a detrimental effect and estrogen may be protective.

Hemostasis in renal disease: pathophysiology and management

The hemostatic abnormalities commonly encountered in patients with renal disease can significantly threaten the well-being of the patient and pose difficult management issues for the clinician. In this review, we explore the pathophysiology underlying the bleeding diathesis and hypercoagulability that can occur. Current therapeutic interventions are also discussed.

Critical care in uraemic children

The special problems posed by renal disease have to be considered when a uraemic child requires intensive care. This report gives an overview on the problems of dialysis treatment, circulatory support, infectious complications, coagulation disorders and increased intracranial pressure.