Significant Decrease In Blood Loss Research Articles

Efficacy of aminocaproic, tranexamic acids in the control of bleeding during total knee replacement: a randomized clinical trial

Risks and costs of allogeneic blood transfusions mandate strategies to reduce blood loss in surgery. The objective of this study was to assess the efficacy of antifibrinolytic treatment in reducing perioperative blood loss during total knee replacement. A double-blind, randomized and placebo-controlled clinical trial was carried out on 127 patients undergoing total knee replacement. Patients in the study group received tranexamic acid 10 mg kg(-1) i.v. just before the tourniquet was deflated and 3 h later, or epsilon-aminocaproic acid 100 mg kg(-1) before tourniquet deflation followed by continuous perfusion (1 g h(-1)) during 3 h. External perioperative blood loss was measured and total blood loss was calculated. The number of patients transfused and number of packed red cell (PRC) units transfused was recorded and possible postoperative thromboembolic complications were investigated. Total blood loss [mean (sd)] was 1099 ml (535) in the group that received antifibrinolytic agents and 1784 ml (660) in the control group (P<0.001). Five patients (7.5%) in the study group and 23 (38.3%) in the control group (P<0.001) received blood transfusions; the first group received a mean of 0.10 PRC unit per patient and the second, 0.58 (P<0.001). Mean reduction in haemoglobin levels (g dl(-1)) between preoperative and fifth day postoperative readings was 2.5 (0.9) in the study group and 3.4 (1.2) in the control group (P<0.001). Clinical assessment did not reveal any thromboembolic complications. Antifibrinolytic agents produce a significant decrease in blood loss in patients undergoing total knee replacement, reflected in a reduction in the number of blood transfusions required.

Recombinant Human FVIIa Reduces Heparin and Low Molecular Weight Heparin (LMWH)-Induced Bleeding in Rats.

Recombinant human FVIIa (rFVIIa, NovoSeven, Novo Nordisk A/S) is approved for treatment of bleeding in hemophilia patients with inhibitors. Recent data indicate that rFVIIa is useful in other bleeding conditions. Heparin and low molecular weight heparin (LMWH) are widely used for anticoagulant management of venous thromboembolic events. Both agents can however cause uncontrollable bleeding. While protamine can reverse the anticoagulant effect of heparin no effective antidote for LMWH is currently available. We have tested if rFVIIa was capable of reducing the bleeding caused by either heparin or LMWH in a rat tail bleeding model. We pre-treated rats with a single dose of either heparin (Heparin, Leo; 200 IU/kg; i.v.) or LMWH (tinzaparin; Innohep, Leo; 500 IU/kg; i.v.), which significantly prolonged total bleeding time following tail transection (table 1). Similarly, blood loss increased significantly by pre-treatment with heparin and tinzaparin (table 2). rFVIIa, intravenously injected 5 minutes after induction of tail bleeding in doses of 5, 10 and 20 mg/kg (n=8), dose-dependently reduced bleeding time of the heparin-induced bleeding, reaching statistical significance at 20 mg/kg (table 1). In accordance, blood loss decreased significantly by treatment with 10 and 20 mg/kg rFVIIa (table 2). A similar response was seen in the tinzaparin pre-treated animals with a dose-dependent decrease in bleeding time (table 1), and a significant decrease in blood loss at 10 and 20 mg/kg rFVIIa (table 2).Table 1Total bleeding time (s)GroupHeparin 200 IU/kg (n=8)#Tinzaparin 500 IU/kg (n=9)#A: No anticoagulant293 ± 68542 ± 180B: Anticoag.+Vehicle1668 ± 83 ***vs. A1800 ± 0 ***vs. AC: Anticoag.+5 mg/kg rFVIIa1194 ± 1821732 ± 45D: Anticoag.+10 mg/kg rFVIIa1023 ± 2301483 ± 152E: Anticoag.+20 mg/kg rFVIIa448 ± 66 **vs. B1038 ± 206 *vs. BData are analyzed using Mann-Whitneys U-test (A-B) or Kruskall-Wallis test with Dunn's post-test (B-E). Asterisks indicate statistical significance at: *: p<0.05; **: p<0.01 and ***: p<0.001. #observation period 1800 s.Table 2Blood loss (nmol hemoglobin/ml)GroupHeparin 200 IU/kg (n=8)#Tinzaparin 500 IU/kg (n=9)#A: No anticoagulant4.2 ± 4.04.9 ± 4.9B: Anticoag.+Vehicle53 ± 19 **vs. A151 ± 37 ***vs. AC: Anticoag.+5 mg/kg rFVIIa10.6 ± 5.632.3 ± 10.3D: Anticoag.+10 mg/kg rFVIIa0.73 ± 0.34 **vs. B7.7 ± 2.8 ***vs. BE: Anticoag.+20 mg/kg rFVIIa4.0 ± 1.9 *vs. B22.6 ± 9.4 *vs. BData are mean ± SEM. Data are analyzed after log transformation using Student's t-test (A-B) or one-way ANOVA with Bonferroni's post-test (B-E). Asterisks indicate statistical significance at: *: p<0.05; **: p<0.01 and ***: p<0.001. #observation period 1800 s.This study illustrates the pharmacological effect of rFVIIa in the presence of heparin and LMWH and the results indicate that rFVIIa may be an effective way to treat heparin and LMWH induced bleeding, however the dose requirements are specific for the rat and cannot be extrapolated to other species. Future studies will investigate the hemostatic effect of rFVIIa in bleedings induced by coumarin analogues, thrombin inhibitors, factor Xa inhibitors, and platelet inhibitors.

Embolization of Craniofacial Vascular Malformations

Craniofacial vascular malformation (CVM) is a major cosmetic concern and may present as catastrophic situations like bleeding apart from the functional impairment. The treatment of CVM has been very challenging. Till the recent past, surgery was the mainstay of treatment. However, because of the torrential intraoperative haemorrhage and frequent recurrences, embolization has evolved as a major adjunct in treating these lesions. This study evaluated the efficacy of various preoperative embolization techniques in the management of CVM. A total of 94 patients (54 males, 40 females) with an age range from three months to 68 years with a mean of 42.4 years having craniofacial AVM (forehead, face, neck and scalp lesions) were treated with the various embolization techniques: Arterial route with (a) hydrogel only (b) hydrogel and gelfoam (c) gel foam only (d) nbutyl cyanoacrylate (NBCA), Venous route and direct puncture injection of NBCA. The devascularisation achieved with the transarterial route was between 80–95% with particulate agents and 95–100% with NBCA. Direct puncture embolization also resulted in near total devascularisation of the lesion. This resulted in a significant decrease in blood loss at surgery. Cure was obtained in a few patients without the need for surgery. After embolization, almost all the patients had mild pain and subtle increase in the swelling with firmer consistency. The embolization of CVM is an essential adjunct to surgery in most cases and can be curative in a few patients. Hydrogel, PVA and gelfoam are good embolizing agents with NBCA being excellent when used with direct puncture.

Evolution of mitral valve surgery: toward a totally endoscopic approach

Background. Our study evaluates a series of video-assisted minimally invasive mitral operations, showing safe progression toward totally endoscopic techniques. Methods. Consecutive patients with isolated mitral valve disease underwent either manually directed (n = 55) or voice-activated robotically directed (n = 72) video-assisted mitral operations. Cold blood cardioplegia, a transthoracic aortic clamp, a 5-mm endoscope, and a 5-cm minithoracotomy were used. This video-assisted minimally invasive mitral operation cohort was compared with a previous sternotomy-based mitral operation cohort (n = 100). Results. Group demographics, New York Heart Association classification, and cardiac function were similar. Repairs were performed in 61.8% manually directed (n = 34), 75.0% robotically directed (n = 54), and 54% sternotomy-based (N = 54) mitral operations. The robotically directed technique showed a significant decrease in blood loss, ventilator time, and hospitalization compared with the sternotomy-based technique. Manually directed mitral operations compared with robotically directed mitral operations had decreased arrest times (128.0 ± 4.5 minutes compared with 90.0 ± 4.6 minutes; p < 0.001) and decreased perfusion times (173.0 ± 5.7 minutes compared with 144.0 ± 4.6 minutes; p < 0.001). In the minimally invasive mitral operation cohort, complications included reexploration for bleeding (2.4%; n = 3) and one stroke (0.8%), whereas the 30-day mortality was 2.3% (n = 3). Conclusions. Video-assisted mitral surgery provides safe and effective results when compared with conventional sternal approaches. These positive results show a safe and stepwise evolution toward a totally endoscopic mitral valve operation.

Early complication of anatomical radical retropubic prostatectomy: lessons from a single-center experience.

The purpose of this study is to report the rate of early complications in 316 of 600 patients who underwent anatomical radical retropubic prostatectomy for localized prostatic cancer from June 1988 to July 1996 and to measure the effect of increasing experience in a single institution. From January 1992 to August 1995, 316 patients with prostatic cancer underwent anatomical radical retropubic prostatectomy at our medical institution. Early complications were recorded prospectively and the rate of complications of the first 166 patients was compared with the rate in the next 150 patients. Comparison of the 2 groups showed a significant decrease in blood loss with time (mean 1,397 vs. 967 cm3, p = 0.0011). The rates of anastomotic urinary leakage (21.7 vs. 10%, p = 0.0056), lymphoceles (22.3 vs. 2%, p < 0.0001), rectal injury (7.8 vs. 2%, p = 0.02), reoperation (10.2 vs. 4%, p = 0.049), and thromboembolic complications (7.8 vs. 2.7%, p = 0.0479) also decreased significantly. Only ureteral transsection showed an increase in the later group (0 vs. 4.7%, p = 0.005). The low percentage of early complications suggests that anatomical retropubic radical prostatectomy is a safe approach. Our single-center study showed a learning pattern that appears unavoidable when this operation is as radical as possible so as to keep the percentage of positive margins low especially in patients with advanced tumors (> pT2).

Tranexamic acid significantly reduces blood loss associated with coronary revascularization

Four hundred fifteen patients undergoing coronary revascularization over a 12-month period were divided into two groups: 209 controls in the first 6 months received no tranexamic acid (TA) before cardiopulmonary bypass and 206 patients in the second 6 months received TA as a hemostatic agent. The demographics and the surgical techniques used were similar in the two groups. With TA there was a significant decrease in blood loss postoperatively, from 1,114.1 mL in the controls to 803.7 mL in those given TA (p < 0.001); in red blood cell use, from 1.7 units/patient in the controls to 0.69 units/patient in those given TA (p < 0.001); in fresh frozen plasma requirements, from 0.23 units/patient in the controls to 0.024 units/patient in those given TA (p < 0.01); and in platelet transfusion, from 1.06 units/patient in the controls to 0.30 units/patients in those given TA (p < 0.01). The percentages of patients not receiving any blood products were 65% in those given TA versus 49% in the controls (p < 0.01). There was no significant difference between the two groups in the incidence of perioperative myocardial infarction, cerebrovascular accidents, pulmonary embolism, or venous thrombosis to clearly suggest hypercoagulability. In this study, TA profoundly affected the coagulopathy associated with bypass in patients undergoing coronary revascularization. It significantly reduced blood loss and blood product transfusions. Any potential increased thrombotic complications could not be clearly demonstrated in this study, but should not be ignored.

Effect of prophylactic epsilon-aminocaproic acid on blood loss and transfusion requirements in patients undergoing first-time coronary artery bypass grafting: A randomized, prospective, double-blind study

The prophylactic use of aprotinin has recently been reported to be associated with a significant decrease in blood loss in patients undergoing cardiopulmonary bypass procedures. One of the primary effects of aprotinin is prevention of plasmin degradation of platelet function. Because aprotinin is commercially unavailable in the United States at this time, we evaluated epsilon-aminocaproic acid with respect to decreased perioperative blood loss. We prospectively randomized 40 patients undergoing first-time coronary artery bypass grafting without prior sternotomy into two groups: one group ( n = 21) received prophylactic and preincision epsilon-aminocaproic acid and the other ( n = 19) received a placebo. No significant differences existed between patient groups with respect to age, body surface area, cardiopulmonary bypass time, and aortic crossclamp time. Cumulative blood loss at 4, 8, 12, and 24 hours after chest closure was significantly less in the epsilon-aminocaproic acid group (426 ± 242 ml versus 634 ± 224 ml, p = 0.002, at 12 hours). Only one patient receiving epsilon-aminocaproic acid was given blood or blood components compared to five patients in the placebo group ( p < 0.02). D-dimers and fibrin split products were significantly less prevalent in the epsilon-aminocaproic acid group (at 4 hours: 0/20 versus 7/16, p < 0.002 and 5/20 versus 12/19, p < 0.05, respectively). None of the patients had a perioperative myocardial infarction or cerebrovascular accident. The prophylactic administration of epsilon-aminocaproic acid results in a significant decrease in blood loss in patients undergoing first-time coronary artery bypass grafting, and blood transfusion requirements are significantly less. It may be important to administer epsilon-aminocaproic acid before skin incision to be optimally effective. (J THORAC CARDIOVASC SURG 1994;108:99-108)

Blood Loss at Time of Cesarean Section by Method of Placental Removal and Exteriorization Versus in Situ Repair of the Uterine Incision

The current study was undertaken to determine if blood loss at the time of cesarean section is affected by method of placental removal (spontaneous versus extracted) or uterine position for repair (in situ versus exteriorized). This prospective randomized study involved 100 women who were undergoing a cesarean section. The patients were placed into one of four groups--1, spontaneous placenta detachment, in situ uterine repair; 2, spontaneous placental detachment, exteriorized uterine repair; 3, manual placental removal, in situ uterine repair, and 4, manual placental removal, exteriorized uterine repair. Patients with spontaneous placental separation (groups 1 and 2) compared with manual removal (groups 3 and 4) revealed a significant decrease in blood loss (p < 0.001). Uterine position did not significantly affect blood loss in the spontaneous group (1 and 2; p = 0.971) or the manual placental removal groups (3 and 4; p = 0.061). The hematocrit values for all groups were similar preoperatively, but postoperatively, were significantly lower in the manual removal groups when compared with the spontaneous placental separation groups (p < 0.001). The method of placental removal and not the position of the uterus at the time of its repair has a significant role in blood loss during cesarean birth.