Heart-Lung Transplantation
Lung Transplantation
Bronchiolitis Obliterans
Lung
Liver Transplantation
Transplantation, Homologous
Primary Graft Dysfunction
Graft Rejection
Bone Marrow Transplantation
Hematopoietic Stem Cell Transplantation
Graft Survival
Tissue Donors
Transplantation, Autologous
MedlinePlus
Angiography, Digital Subtraction
Ventilation-Perfusion Ratio
Technetium Tc 99m Aggregated Albumin
Pulmonary Artery
Pulmonary ischemia/reperfusion injury: a quantitative study of structure and function in isolated heart-lungs of the rat. (1/140)
Early graft dysfunction after lung transplantation is a significant and unpredictable problem. Our study aimed at a detailed investigation of structure-function correlations in a rat isolated heart-lung model ofischemia/ reperfusion injury. Variable degrees of injury were induced by preservation with potassium-modified Euro-Collins solutions, 2 hr of cold ischemia, and 40 min of reperfusion. Pulmonary artery pressure (Ppa), pulmonary vascular resistance (PVR), peak inspiratory pressure (PIP), and perfusate gases (deltaPO2, deltaPCO2) were recorded during reperfusion. Right lungs were used to calculate W/D-weight ratios. Nineteen experimental and six control left lungs were fixed for light and electron microscopy by vascular perfusion. Systematic random samples were analyzed by stereology to determine absolute and relative volumes of lung structures, the amount of interstitial and intraalveolar edema, and the extent of epithelial injury. Lectin- and immunohistochemistry using established epithelial cell markers were performed in three animals per group to reveal sites of severe focal damage. Experimental lungs showed a wide range in severity of ischemia/ reperfusion injury. Intraalveolar edema fluid amounted to 77-909 mm3 with a mean of 448+/-250 mm3 as compared with 22+/-22 mm3 in control lungs (P<0.001). Perfusate oxygenation (deltaPO2) decreased from 30.5+/-15.2 to 21.7+/-15.2 mm Hg (P=0.05) recorded after 5 and 40 minutes of reperfusion. In experimental lungs, a surface fraction of 1% to 58% of total type I pneumocyte surface was damaged. Intraalveolar edema per gas exchange region (Vv ape,P) and deltaPO2 were related according to deltaPO2 = 96 - 60 x log10(Vv ape,P) [mm Hg]. The extent of epithelial injury did not correlate with deltaPO2 nor with intraalveolar edema, but increased significantly with PVR. Lectin- and immunohistochemistry revealed focal severe damage to the alveolar epithelium at the border of perivascular cuffs. (+info)The porcine bronchial artery. Anastomoses with oesophageal, coronary and intercostal arteries. (2/140)
Information about the existence and anatomy of arterial anastomoses with the porcine bronchial artery is lacking in the literature. Prior to basic physiological investigations in a porcine model related to lung transplantation with bronchial artery revascularisation, this study was designed to examine the anatomy of systemic arterial anastomoses with the bronchial artery system. Twenty pigs were studied in 3 groups. In 2 groups the heart-lung block was removed with all mediastinal structures. One group served for investigation of coronary-bronchial artery anastomoses and one for investigation of oesophageal-bronchial artery anastomoses. The systemic arteries to be examined were cannulated. The inflated heart-lung block was examined macroscopically with Evans blue, and radiographically after contrast injection. In the 3rd group intercostobronchial artery anastomoses were studied radiographically with the heart-lung block in situ. Coronary-bronchial artery anastomoses were demonstrated in 3 of the 5 pigs with an aortic 'pouch' technique, but contrast was very limited in 2 of these 3. Oesophageal arterial anastomoses with bronchial arterial branches and/or the pulmonary veins were demonstrated in 6 of the 7 pigs and more markedly than the coronary-bronchial anastomoses. Intercostobronchial artery anastomoses could not be demonstrated angiographically. It was concluded that the existence of coronary-bronchial and oesophageal-bronchial artery anastomoses in the pig appear to establish an arterial net between the base of the heart and the distal oesophagus. The resemblance to human oesophageal-bronchial artery anastomoses supports use of a porcine model for experimental studies. (+info)The history and development of cardiac transplantation. (3/140)
The history of heart surgery, spanning only 100 years to date, has seen some of the most daring and persistent men and women in all of medical history. Many aspects of heart surgery, including such innovations as the heart-lung machine, aortic aneurysm surgery, and the correction of congenital heart defects, have provided future surgeons with an important lesson: diligent research can solve complex problems. The history and development of cardiac transplantation is particularly full of challenges that have been overcome, with the research phase alone spanning more than 90 years. During that time, essential contributions came from all over the world, including the United States, Russia, England, and South Africa. As is typical of medical advancement, individual contributions did not stand alone but added to the experience of those who had come before. Even so, the work of a few particular groups deserves special recognition. Most notable is the Stanford team, led by Dr. Norman Shumway, who continued to transplant human hearts when other institutions had abandoned hopes for the operation. Largely because of the commitment of that team, cardiac transplantation has become a standard option in the treatment of end-stage heart disease. Currently, only the availability of donor hearts limits the number of cardiac transplantations performed worldwide. (+info)Haemodynamic response to dynamic exercise after heart-lung transplantation. (4/140)
The purpose of this study was to investigate the haemodynamic response to dynamic exercise after heart-lung transplantation (HLT). Nine stable HLT recipients (6 males) were studied 12-55 months after transplantation. While sitting on a cycle ergometer, they first underwent a maximal symptom-limited exercise test (power increment was 10 W x min(-1)) to determine the maximal tolerable workload. On the next day, they performed a second exercise test at 0, 40, 60 and 80% of their predetermined maximal workload (mean+/-sD: 108+/-20 W). Stage duration was 6 min. Respiratory, gas exchange, and haemodynamic measurements were performed at rest, during the last minute of each stage, and after recovery. Haemodynamic variables at rest were within normal limits except heart rate (HR) which was greater and stroke volume index (SVI) which was lower than normal. Peak oxygen consumption was 61+/-8% of predicted. HR showed an initial slow increase followed by a steeper rise, and a delayed return to baseline during the recovery period. SVI and cardiac index (CI) increased at the onset of exercise but did not change significantly at 40-80% of the maximal workload. Pulmonary capillary wedge pressure increased from 4+/-2 mmHg at rest to 14+/-3 mmHg at maximal exercise. It is concluded that during dynamic exercise, heart-lung transplantation recipients demonstrate a chronotropic incompetence, a reduced increase in cardiac index and stroke volume index, and an excessive rise in left ventricular filling pressures. These alterations may contribute to the persistent exercise limitation. (+info)Vagal feedback in the entrainment of respiration to mechanical ventilation in sleeping humans. (5/140)
We studied the capacity of four "normal" and six lung transplant subjects to entrain neural respiratory activity to mechanical ventilation. Two transplant subjects were studied during wakefulness and demonstrated entrainment indistinguishable from that of normal awake subjects. We studied four normal subjects and four lung transplant subjects during non-rapid eye movement (NREM) sleep. Normal subjects entrained to mechanical ventilation over a range of ventilator frequencies that were within +/-3-5 breaths of the spontaneous respiratory rate of each subject. After lung transplantation, during which the vagi were cut, subjects did demonstrate entrainment during NREM sleep; however, entrainment only occurred at ventilator frequencies at or above each subject's spontaneous respiratory rate, and entrainment was less effective. We conclude that there is no absolute requirement for vagal feedback to induce entrainment in subjects, which is in striking contrast to anesthetized animals in which vagotomy uniformly abolishes entrainment. On the other hand, vagal feedback clearly enhances the fidelity of entrainment and extends the range of mechanical frequencies over which entrainment can occur. (+info)Cyclosporine metabolism in patients after kidney, bone marrow, heart-lung, and liver transplantation in the early and late posttransplant periods. (6/140)
Cyclosporine is used in the prevention of allograft rejection. Owing to its narrow therapeutic index, regular monitoring of the whole blood levels of cyclosporine is required. We observed that immunoassays measured significantly higher cyclosporine levels than did high-performance liquid chromatography (HPLC) over time after transplantation. As cyclosporine metabolites cross-react even with immunoassays, this observation might be due to alterations of the cyclosporine metabolism. We analyzed cyclosporine metabolite concentrations in the early and in the late posttransplantation periods in 127 patients after kidney, bone marrow, heart-lung, and liver transplantation by HPLC and determined whole blood levels of cyclosporine by 4 immunoassays (enzyme-multiplied immunoassay [EMIT], cloned enzyme donor immunoassay [CEDIA], AxSYM [Abbott Laboratories, Chicago, IL], and TDx [Abbott Laboratories]). Despite reduced dose, we found significantly higher cyclosporine concentrations measured by the EMIT, AxSYM, and TDx assays in various patient groups. These results are due to the increased metabolite/cyclosporine ratio in the late posttransplantation period. In particular, the metabolites AM1 and AM19 increased significantly over time in bone marrow transplant recipients. Therefore, cyclosporine levels measured by immunoassays should be interpreted with caution. (+info)Effect of preoperative hyperinflation on static lung volumes after lung transplantation. (7/140)
It is still not known whether persistent increases in functional residual capacity (FRC) and residual volume (RV) after lung transplantation are due to preexisting hyperinflation. Therefore, the aim of this study was to determine the effects of chronic lung hyperinflation on static lung volumes after heart/lung (HLT) and bilateral lung transplantation (BLT). Static lung volumes were measured in 33 patients before and at 6 month intervals for up to 3 yrs after HLT (n=25) or BLT (n=8). The preoperative diagnosis was cystic fibrosis in 25 patients and other chronic hyperinflated lung diseases in eight patients. After surgery, total lung capacity returned to predicted normal values but FRC and RV remained greater than expected for either the recipient or the donor. At 1 yr after surgery, mean+/-SD FRC and RV were 130+/-18% and 151+/-34% of the predicted values for the recipient (p<0.001), and these figures did not change significantly over time. Similar abnormalities were found in patients with and without cystic fibrosis. After transplantation for lung diseases producing chronic hyperinflation, there is a persistent increase in functional residual capacity and residual volume. This alteration is present in patients operated on for diseases developed in both childhood and adulthood and is not recovered over time. It may be due to irreversible changes in the structure of the ribcage. (+info)Nocardia infection in heart-lung transplant recipients at Alfred Hospital, Melbourne, Australia, 1989-1998. (8/140)
Nocardia infections are uncommon in recipients of heart, lung, or heart-lung transplants, but such infections are well described. Frequent episodes of rejection, high-dose prednisolone treatment, renal impairment, and prolonged respiratory support have all been shown to increase the risk of Nocardia infection in this group. In this retrospective review of 540 recipients of heart, lung, or heart-lung transplants, 10 patients developed Nocardia infection (frequency, 1.85%). Infection occurred at a mean +/- standard deviation of 13+/-14.5 months after transplantation. All patients had pulmonary disease with no evidence of extrapulmonary disease. The Nocardia infection did not contribute directly to patient deaths. Coinfection with other pathogens was present in 6 patients, and 2 patients had sequential infections. Radiological findings varied. All isolates were susceptible to trimethoprim-sulfamethoxazole, amikacin, and imipenem. Treatment regimens varied. Two (30%) of 6 patients treated with trimethoprim-sulfamethoxazole developed adverse reactions, which necessitated a change in antibiotic therapy. The optimal treatment regimen, which comprises both the antimicrobial agent and the length of treatment, is unclear. (+info)Heart-lung transplantation is a surgical procedure where both the heart and lungs of a patient are replaced with those from a deceased donor. This complex and highly specialized surgery is typically considered as a last resort for patients suffering from end-stage lung or heart-lung diseases, such as cystic fibrosis, pulmonary fibrosis, chronic obstructive pulmonary disease (COPD), or certain forms of congenital heart disease, who have exhausted all other treatment options and face imminent death.
The procedure involves removing the patient's diseased heart and lungs en bloc, followed by implanting the donor's heart and lungs in their place. The surgery requires a skilled multidisciplinary team of cardiothoracic surgeons, anesthesiologists, perfusionists, transplant coordinators, and intensive care specialists.
Following the transplantation, patients require lifelong immunosuppressive therapy to prevent rejection of the transplanted organs. Despite the significant risks associated with this procedure, including infection, bleeding, and rejection, heart-lung transplantation can significantly improve both survival and quality of life for carefully selected patients with advanced heart-lung disease.
Lung transplantation is a surgical procedure where one or both diseased lungs are removed and replaced with healthy lungs from a deceased donor. It is typically considered as a treatment option for patients with end-stage lung diseases, such as chronic obstructive pulmonary disease (COPD), cystic fibrosis, idiopathic pulmonary fibrosis, and alpha-1 antitrypsin deficiency, who have exhausted all other medical treatments and continue to suffer from severe respiratory failure.
The procedure involves several steps, including evaluating the patient's eligibility for transplantation, matching the donor's lung size and blood type with the recipient, and performing the surgery under general anesthesia. After the surgery, patients require close monitoring and lifelong immunosuppressive therapy to prevent rejection of the new lungs.
Lung transplantation can significantly improve the quality of life and survival rates for some patients with end-stage lung disease, but it is not without risks, including infection, bleeding, and rejection. Therefore, careful consideration and thorough evaluation are necessary before pursuing this treatment option.
Bronchiolitis obliterans is a medical condition characterized by the inflammation and scarring (fibrosis) of the bronchioles, which are the smallest airways in the lungs. This results in the narrowing or complete obstruction of the airways, leading to difficulty breathing and reduced lung function.
The condition is often caused by a respiratory infection, such as adenovirus or mycoplasma pneumonia, but it can also be associated with exposure to certain chemicals, drugs, or radiation therapy. In some cases, the cause may be unknown.
Symptoms of bronchiolitis obliterans include cough, shortness of breath, wheezing, and crackles heard on lung examination. Diagnosis typically involves a combination of medical history, physical exam, imaging studies (such as chest X-ray or CT scan), and pulmonary function tests. In some cases, a biopsy may be necessary to confirm the diagnosis.
Treatment for bronchiolitis obliterans is focused on managing symptoms and preventing further lung damage. This may include bronchodilators to help open up the airways, corticosteroids to reduce inflammation, and oxygen therapy to help with breathing. In severe cases, a lung transplant may be necessary.
A lung is a pair of spongy, elastic organs in the chest that work together to enable breathing. They are responsible for taking in oxygen and expelling carbon dioxide through the process of respiration. The left lung has two lobes, while the right lung has three lobes. The lungs are protected by the ribcage and are covered by a double-layered membrane called the pleura. The trachea divides into two bronchi, which further divide into smaller bronchioles, leading to millions of tiny air sacs called alveoli, where the exchange of gases occurs.
Liver transplantation is a surgical procedure in which a diseased or failing liver is replaced with a healthy one from a deceased donor or, less commonly, a portion of a liver from a living donor. The goal of the procedure is to restore normal liver function and improve the patient's overall health and quality of life.
Liver transplantation may be recommended for individuals with end-stage liver disease, acute liver failure, certain genetic liver disorders, or liver cancers that cannot be treated effectively with other therapies. The procedure involves complex surgery to remove the diseased liver and implant the new one, followed by a period of recovery and close medical monitoring to ensure proper function and minimize the risk of complications.
The success of liver transplantation has improved significantly in recent years due to advances in surgical techniques, immunosuppressive medications, and post-transplant care. However, it remains a major operation with significant risks and challenges, including the need for lifelong immunosuppression to prevent rejection of the new liver, as well as potential complications such as infection, bleeding, and organ failure.
Homologous transplantation is a type of transplant surgery where organs or tissues are transferred between two genetically non-identical individuals of the same species. The term "homologous" refers to the similarity in structure and function of the donated organ or tissue to the recipient's own organ or tissue.
For example, a heart transplant from one human to another is an example of homologous transplantation because both organs are hearts and perform the same function. Similarly, a liver transplant, kidney transplant, lung transplant, and other types of organ transplants between individuals of the same species are also considered homologous transplantations.
Homologous transplantation is in contrast to heterologous or xenogeneic transplantation, where organs or tissues are transferred from one species to another, such as a pig heart transplanted into a human. Homologous transplantation is more commonly performed than heterologous transplantation due to the increased risk of rejection and other complications associated with xenogeneic transplants.
Primary graft dysfunction (PGD) is a severe complication that can occur after an organ transplant, such as a lung or heart transplant. It refers to the early functional impairment of the grafted organ that is not due to surgical complications, rejection, or recurrence of the original disease.
In the case of lung transplants, PGD is defined as the evidence of poor oxygenation and stiffness in the lungs within the first 72 hours after the transplant. It is typically caused by inflammation, injury to the blood vessels, or other damage to the lung tissue during the transplant procedure or due to pre-existing conditions in the donor organ.
PGD can lead to serious complications, including respiratory failure, and is associated with increased morbidity and mortality after transplantation. Treatment may include supportive care, such as mechanical ventilation and medications to support lung function, as well as strategies to reduce inflammation and prevent further damage to the grafted organ.
In medical terms, the heart is a muscular organ located in the thoracic cavity that functions as a pump to circulate blood throughout the body. It's responsible for delivering oxygen and nutrients to the tissues and removing carbon dioxide and other wastes. The human heart is divided into four chambers: two atria on the top and two ventricles on the bottom. The right side of the heart receives deoxygenated blood from the body and pumps it to the lungs, while the left side receives oxygenated blood from the lungs and pumps it out to the rest of the body. The heart's rhythmic contractions and relaxations are regulated by a complex electrical conduction system.
Graft rejection is an immune response that occurs when transplanted tissue or organ (the graft) is recognized as foreign by the recipient's immune system, leading to the activation of immune cells to attack and destroy the graft. This results in the failure of the transplant and the need for additional medical intervention or another transplant. There are three types of graft rejection: hyperacute, acute, and chronic. Hyperacute rejection occurs immediately or soon after transplantation due to pre-existing antibodies against the graft. Acute rejection typically occurs within weeks to months post-transplant and is characterized by the infiltration of T-cells into the graft. Chronic rejection, which can occur months to years after transplantation, is a slow and progressive process characterized by fibrosis and tissue damage due to ongoing immune responses against the graft.
Heart transplantation is a surgical procedure where a diseased, damaged, or failing heart is removed and replaced with a healthy donor heart. This procedure is usually considered as a last resort for patients with end-stage heart failure or severe coronary artery disease who have not responded to other treatments. The donor heart typically comes from a brain-dead individual whose family has agreed to donate their loved one's organs for transplantation. Heart transplantation is a complex and highly specialized procedure that requires a multidisciplinary team of healthcare professionals, including cardiologists, cardiac surgeons, anesthesiologists, perfusionists, nurses, and other support staff. The success rates for heart transplantation have improved significantly over the past few decades, with many patients experiencing improved quality of life and increased survival rates. However, recipients of heart transplants require lifelong immunosuppressive therapy to prevent rejection of the donor heart, which can increase the risk of infections and other complications.
Kidney transplantation is a surgical procedure where a healthy kidney from a deceased or living donor is implanted into a patient with end-stage renal disease (ESRD) or permanent kidney failure. The new kidney takes over the functions of filtering waste and excess fluids from the blood, producing urine, and maintaining the body's electrolyte balance.
The transplanted kidney is typically placed in the lower abdomen, with its blood vessels connected to the recipient's iliac artery and vein. The ureter of the new kidney is then attached to the recipient's bladder to ensure proper urine flow. Following the surgery, the patient will require lifelong immunosuppressive therapy to prevent rejection of the transplanted organ by their immune system.
Lung diseases refer to a broad category of disorders that affect the lungs and other structures within the respiratory system. These diseases can impair lung function, leading to symptoms such as coughing, shortness of breath, chest pain, and wheezing. They can be categorized into several types based on the underlying cause and nature of the disease process. Some common examples include:
1. Obstructive lung diseases: These are characterized by narrowing or blockage of the airways, making it difficult to breathe out. Examples include chronic obstructive pulmonary disease (COPD), asthma, bronchiectasis, and cystic fibrosis.
2. Restrictive lung diseases: These involve stiffening or scarring of the lungs, which reduces their ability to expand and take in air. Examples include idiopathic pulmonary fibrosis, sarcoidosis, and asbestosis.
3. Infectious lung diseases: These are caused by bacteria, viruses, fungi, or parasites that infect the lungs. Examples include pneumonia, tuberculosis, and influenza.
4. Vascular lung diseases: These affect the blood vessels in the lungs, impairing oxygen exchange. Examples include pulmonary embolism, pulmonary hypertension, and chronic thromboembolic pulmonary hypertension (CTEPH).
5. Neoplastic lung diseases: These involve abnormal growth of cells within the lungs, leading to cancer. Examples include small cell lung cancer, non-small cell lung cancer, and mesothelioma.
6. Other lung diseases: These include interstitial lung diseases, pleural effusions, and rare disorders such as pulmonary alveolar proteinosis and lymphangioleiomyomatosis (LAM).
It is important to note that this list is not exhaustive, and there are many other conditions that can affect the lungs. Proper diagnosis and treatment of lung diseases require consultation with a healthcare professional, such as a pulmonologist or respiratory therapist.
Bone marrow transplantation (BMT) is a medical procedure in which damaged or destroyed bone marrow is replaced with healthy bone marrow from a donor. Bone marrow is the spongy tissue inside bones that produces blood cells. The main types of BMT are autologous, allogeneic, and umbilical cord blood transplantation.
In autologous BMT, the patient's own bone marrow is used for the transplant. This type of BMT is often used in patients with lymphoma or multiple myeloma who have undergone high-dose chemotherapy or radiation therapy to destroy their cancerous bone marrow.
In allogeneic BMT, bone marrow from a genetically matched donor is used for the transplant. This type of BMT is often used in patients with leukemia, lymphoma, or other blood disorders who have failed other treatments.
Umbilical cord blood transplantation involves using stem cells from umbilical cord blood as a source of healthy bone marrow. This type of BMT is often used in children and adults who do not have a matched donor for allogeneic BMT.
The process of BMT typically involves several steps, including harvesting the bone marrow or stem cells from the donor, conditioning the patient's body to receive the new bone marrow or stem cells, transplanting the new bone marrow or stem cells into the patient's body, and monitoring the patient for signs of engraftment and complications.
BMT is a complex and potentially risky procedure that requires careful planning, preparation, and follow-up care. However, it can be a life-saving treatment for many patients with blood disorders or cancer.
Hematopoietic Stem Cell Transplantation (HSCT) is a medical procedure where hematopoietic stem cells (immature cells that give rise to all blood cell types) are transplanted into a patient. This procedure is often used to treat various malignant and non-malignant disorders affecting the hematopoietic system, such as leukemias, lymphomas, multiple myeloma, aplastic anemia, inherited immune deficiency diseases, and certain genetic metabolic disorders.
The transplantation can be autologous (using the patient's own stem cells), allogeneic (using stem cells from a genetically matched donor, usually a sibling or unrelated volunteer), or syngeneic (using stem cells from an identical twin).
The process involves collecting hematopoietic stem cells, most commonly from the peripheral blood or bone marrow. The collected cells are then infused into the patient after the recipient's own hematopoietic system has been ablated (or destroyed) using high-dose chemotherapy and/or radiation therapy. This allows the donor's stem cells to engraft, reconstitute, and restore the patient's hematopoietic system.
HSCT is a complex and potentially risky procedure with various complications, including graft-versus-host disease, infections, and organ damage. However, it offers the potential for cure or long-term remission in many patients with otherwise fatal diseases.
Graft survival, in medical terms, refers to the success of a transplanted tissue or organ in continuing to function and integrate with the recipient's body over time. It is the opposite of graft rejection, which occurs when the recipient's immune system recognizes the transplanted tissue as foreign and attacks it, leading to its failure.
Graft survival depends on various factors, including the compatibility between the donor and recipient, the type and location of the graft, the use of immunosuppressive drugs to prevent rejection, and the overall health of the recipient. A successful graft survival implies that the transplanted tissue or organ has been accepted by the recipient's body and is functioning properly, providing the necessary physiological support for the recipient's survival and improved quality of life.
A tissue donor is an individual who has agreed to allow organs and tissues to be removed from their body after death for the purpose of transplantation to restore the health or save the life of another person. The tissues that can be donated include corneas, heart valves, skin, bone, tendons, ligaments, veins, and cartilage. These tissues can enhance the quality of life for many recipients and are often used in reconstructive surgeries. It is important to note that tissue donation does not interfere with an open casket funeral or other cultural or religious practices related to death and grieving.
Autologous transplantation is a medical procedure where cells, tissues, or organs are removed from a person, stored and then returned back to the same individual at a later time. This is different from allogeneic transplantation where the tissue or organ is obtained from another donor. The term "autologous" is derived from the Greek words "auto" meaning self and "logos" meaning study.
In autologous transplantation, the patient's own cells or tissues are used to replace or repair damaged or diseased ones. This reduces the risk of rejection and eliminates the need for immunosuppressive drugs, which are required in allogeneic transplants to prevent the body from attacking the foreign tissue.
Examples of autologous transplantation include:
* Autologous bone marrow or stem cell transplantation, where stem cells are removed from the patient's blood or bone marrow, stored and then reinfused back into the same individual after high-dose chemotherapy or radiation therapy to treat cancer.
* Autologous skin grafting, where a piece of skin is taken from one part of the body and transplanted to another area on the same person.
* Autologous chondrocyte implantation, where cartilage cells are harvested from the patient's own knee, cultured in a laboratory and then implanted back into the knee to repair damaged cartilage.
Heart rate is the number of heartbeats per unit of time, often expressed as beats per minute (bpm). It can vary significantly depending on factors such as age, physical fitness, emotions, and overall health status. A resting heart rate between 60-100 bpm is generally considered normal for adults, but athletes and individuals with high levels of physical fitness may have a resting heart rate below 60 bpm due to their enhanced cardiovascular efficiency. Monitoring heart rate can provide valuable insights into an individual's health status, exercise intensity, and response to various treatments or interventions.
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A pulmonary embolism (PE) is a medical condition that occurs when a blood clot, often formed in the deep veins of the legs (deep vein thrombosis), breaks off and travels to the lungs, blocking one or more pulmonary arteries. This blockage can lead to various symptoms such as shortness of breath, chest pain, rapid heart rate, and coughing up blood. In severe cases, it can cause life-threatening complications like low oxygen levels, hypotension, and even death if not promptly diagnosed and treated with anticoagulant medications or thrombolytic therapy to dissolve the clot.
Angiography is a medical procedure in which an x-ray image is taken to visualize the internal structure of blood vessels, arteries, or veins. This is done by injecting a radiopaque contrast agent (dye) into the blood vessel using a thin, flexible catheter. The dye makes the blood vessels visible on an x-ray image, allowing doctors to diagnose and treat various medical conditions such as blockages, narrowing, or malformations of the blood vessels.
There are several types of angiography, including:
* Cardiac angiography (also called coronary angiography) - used to examine the blood vessels of the heart
* Cerebral angiography - used to examine the blood vessels of the brain
* Peripheral angiography - used to examine the blood vessels in the limbs or other parts of the body.
Angiography is typically performed by a radiologist, cardiologist, or vascular surgeon in a hospital setting. It can help diagnose conditions such as coronary artery disease, aneurysms, and peripheral arterial disease, among others.
Digital subtraction angiography (DSA) is a medical imaging technique used to visualize the blood vessels and blood flow within the body. It combines the use of X-ray technology with digital image processing to produce detailed images of the vascular system.
In DSA, a contrast agent is injected into the patient's bloodstream through a catheter, which is typically inserted into an artery in the leg and guided to the area of interest using fluoroscopy. As the contrast agent flows through the blood vessels, X-ray images are taken at multiple time points.
The digital subtraction process involves taking a baseline image without contrast and then subtracting it from subsequent images taken with contrast. This allows for the removal of background structures and noise, resulting in clearer images of the blood vessels. DSA can be used to diagnose and evaluate various vascular conditions, such as aneurysms, stenosis, and tumors, and can also guide interventional procedures such as angioplasty and stenting.
The Ventilation-Perfusion (V/Q) ratio is a measure used in respiratory physiology to describe the relationship between the amount of air that enters the alveoli (ventilation) and the amount of blood that reaches the alveoli to pick up oxygen (perfusion).
In a healthy lung, these two processes are well-matched, meaning that well-ventilated areas of the lung also have good blood flow. This results in a V/Q ratio close to 1.0.
However, certain lung conditions such as emphysema or pulmonary embolism can cause ventilation and perfusion to become mismatched, leading to a V/Q ratio that is either higher (ventilation exceeds perfusion) or lower (perfusion exceeds ventilation) than normal. This mismatch can result in impaired gas exchange and lead to hypoxemia (low oxygen levels in the blood).
The V/Q ratio is often used in clinical settings to assess lung function and diagnose respiratory disorders.
Technetium Tc 99m Aggregated Albumin is a radiopharmaceutical preparation used in diagnostic imaging. It consists of radioactive technetium-99m (^99m^Tc) chemically bonded to human serum albumin, which has been aggregated to increase its size and alter its clearance from the body.
The resulting compound is injected into the patient's bloodstream, where it accumulates in the reticuloendothelial system (RES), including the liver, spleen, and bone marrow. The radioactive emission of technetium-99m can then be detected by a gamma camera, producing images that reflect the distribution and function of the RES.
This imaging technique is used to diagnose and monitor various conditions, such as liver disease, inflammation, or tumors. It provides valuable information about the patient's health status and helps guide medical decision-making.
The pulmonary artery is a large blood vessel that carries deoxygenated blood from the right ventricle of the heart to the lungs for oxygenation. It divides into two main branches, the right and left pulmonary arteries, which further divide into smaller vessels called arterioles, and then into a vast network of capillaries in the lungs where gas exchange occurs. The thin walls of these capillaries allow oxygen to diffuse into the blood and carbon dioxide to diffuse out, making the blood oxygen-rich before it is pumped back to the left side of the heart through the pulmonary veins. This process is crucial for maintaining proper oxygenation of the body's tissues and organs.
Sodium Pertechnetate Tc 99m is a radioactive pharmaceutical preparation used in medical diagnostic imaging. It is a technetium-99m radiopharmaceutical, where technetium-99m is a metastable nuclear isomer of technetium-99, which emits gamma rays and has a half-life of 6 hours. Sodium Pertechnetate Tc 99m is used as a contrast agent in various diagnostic procedures, such as imaging of the thyroid, salivary glands, or the brain, to evaluate conditions like inflammation, tumors, or abnormalities in blood flow. It is typically administered intravenously, and its short half-life ensures that the radiation exposure is limited.