Blood
David Sturgeon in Introduction to Anatomy and Physiology for Healthcare Students, 2018
A blood transfusion is normally provided to replace intravascular volume following a bleed (e.g. during/after surgery or trauma) or to correct a blood cell or haemoglobin deficit (e.g. anaemia or bone marrow failure). In these circumstances, the recipient will almost certainly receive blood donated from somebody else. However, not all blood types are compatible and it is essential that transfused blood is appropriately matched to the recipient’s blood type or group. There are four blood types (A, B, AB and O) and they are named according to the presence or absence of antigens on the surface of the erythrocyte membrane (Figure 5.3). An antigen is a substance that is recognised as a threat by the immune system and triggers the formation of an antibody or immunoglobulin (Ig) to destroy it. Luckily for us, our immune system ignores the surface antigens on our own erythrocytes (and other cells) and antigens can be considered in much the same way as a badge or security pass. In the case of blood transfusion, if erythrocytes have the correct security pass/antigen, the immune system will ignore them (since they are ‘self’) and allow access to the circulatory system. If they have the wrong security pass/antigen, the immune system will destroy them in a fairly unpleasant way. However, there is always an exception to the rule and blood type O is able to access the circulatory system without detection since it displays no antigens (very James Bond).
Obstetrics: Answers
Euan Kevelighan, Jeremy Gasson, Makiya Ashraf in Get Through MRCOG Part 2: Short Answer Questions, 2020
Her antenatal care should be managed by a multidisciplinary team consisting of a haematologist, an anaesthetist and an obstetrician with an interest in maternal medicine (1). She should be advised to take folic acid supplementation at 5 mg/day, and it is important to confirm she is taking penicillin V 250 mg b.d. (as hyposplenism is common) and that she is up to date with hepatitis B and pneumococcal vaccines (1). The maternal and fetal risks should be explained and the need for close monitoring during pregnancy emphasized (1). She should be encouraged to avoid dehydration and cold environments, as either may trigger a sickling crisis. If she suspects infection or an impending crisis, she should seek medical help urgently (1). Blood transfusion may be required, e.g. for severe anaemia, and exchange transfusion if the patient is volume replete. Exchange transfusion is controversial in pregnancy, so expert haematological advice is essential (1).
Breast tumours
Harold Ellis, Sala Abdalla in A History of Surgery, 2018
The apparent logical extension of these pathological findings was to attempt to increase the radicality of the radical mastectomy. Erling Dahl-Iverson (1892–1978) at the Rigshospitalet, Copenhagen, in 1951 performed an extrapleural dissection of the internal mammary nodes, as did Mario Margottini (1897–1970) of the National Cancer Institute, Rome, the following year, while Owen Wangensteen (1898–1981) in Minneapolis advised splitting the sternum to remove the internal mammary nodes and dissection of the nodes above the clavicle. But it was Jerry Urban (1914–1991) at the Memorial Hospital, New York, who perfected a massive operation that combined radical mastectomy with en bloc resection of the internal mammary chain by removal of part of the sternum together with the inner ends of the second to the fifth rib and with repair of the resultant defect with fascia taken from the thigh. This operation took about 5 hours and required on average a three-pint blood transfusion (Figure 11.14).
Safety and efficacy of tranexamic acid in spinal canal tumors: a retrospective cohort study
Published in British Journal of Neurosurgery, 2020
Heng Zhu Zhang, Lun Dong, Huan Ming Wang, Fei Hu, Qiang Shao, Xu Chen, Lang Chen
There are many surgical methods for tumor resection in the spinal canal. Neurosurgeons aim to remove the entire tumor while maintaining the stability of the spine. Commonly available surgical approaches include laminectomy, hemilaminectomy, and the ‘archbone’ technique. The archbone technique1 is less traumatic as laminae and spinous processes are not separated from their muscle attachments, the average blood loss with this approach is 158 ml. Clinically, intraoperative blood loss may be great when removing some multi-segment, huge, spinal tumors, especially metastatic tumors. Although blood transfusions can be used to address this problem, they also pose potential risks, such as cross-infection and the spread of blood diseases.6 Elgafy et al.7 conducted a retrospective analysis of drugs used to reduce bleeding during spinal surgery over the past two decades. They found that TXA reduces the amount of bleeding during spine surgery and homologous blood transfusion. TXA is used for spinal deformity operations2 and thoracic fusion surgery in adult patients.8 There is evidence9 that TXA can reduce intraoperative bleeding.
A novel missense variant in the RASGRP2 gene in patients with moderate to severe bleeding disorder
Published in Platelets, 2020
Essa Alharby, Mohammad A Bakhsh, Alia M Albalawi, Sultan O Almutairi, Jamil A Hashmi, Sulman Basit
Both affected individuals (IV:1, IV:4) were born after asymptomatic pregnancies and are currently 13 years and 9 years old, respectively. Both individuals suffered from mucocutaneous bleeding starting at the age of 1 year. Prolonged bleeding after tooth extraction and severe epistaxis were observed. Recurrent blood transfusions were performed. Clinical examination of both parents and two unaffected siblings did not reveal any bleeding tendency. The bleeding times in unaffected individuals 5–6 min. International society of thrombosis and hemostasis bleeding assessment tool (ISTH-BAT) was used to calculate an overall bleeding score. The overall bleeding score for the clinical symptoms of affected individuals IV:1 and IV:4 was 15 and 12, respectively (Table II).
Characteristics of Nontrauma Patients Receiving Prehospital Blood Transfusion with the Same Triggers as Trauma Patients: A Retrospective Observational Cohort Study
Published in Prehospital Emergency Care, 2022
Susanne Ångerman, Hetti Kirves, Jouni Nurmi
Majority of the patients in both groups received blood transfusions in the hospital within 12 hours. However, it is possible that some patients were overtransfused due to the challenging diagnostics and decision-making in the prehospital setting. The shock index, acquired by dividing the heart rate by the systolic blood pressure, is an established and validated tool for identifying hemodynamically instable trauma patients (27, 28). It has recently been developed further to achieve more precise tools, such as modified shock index and age shock index (29). Furthermore, PHBT therapy could probably be targeted more precisely by analyzing point-of-care markers, such as lactate. In a study by Guyette et al., prehospital lactate outperformed shock index and systolic blood pressure in detection of resuscitative interventions in 387 trauma patients (30). The same physiological triggers may not be optimal in all age groups. In the current study, nontrauma patients were significantly older than trauma patients. This finding needs to be considered when evaluating the age-related transfusion criteria in the future.
Related Knowledge Centers
- Coagulation
- White Blood Cell
- Platelet
- Circulatory System
- Hemoglobin
- Red Blood Cell
- Blood Plasma
- Blood Product
- Intravenous Therapy
- Whole Blood