It is quite common to have blood transfusions after cardiac surgery, although the rates vary among different hospitals. Although common, transfusion always carries the risk of infectious as well as noninfectious hazards. Moreover, blood transfusions are not clinically necessary (in at least 50 per cent of the cases) . Bloodless surgery is not something entirely new, its discovery and roots date back to several years ago.
Every year, World Health Day is observed on 7 April. WHO always works with a goal and motive to make basic healthcare accessible to one and all and it idealizes this mission each year on this special day. With an aim to make provision of medical aid quick and easy, every health care practitioner is bound to dedicate supreme service to every patient he or she treats with the patient's safety and quick recovery as the top priority.
So, on this World Health Day, let's talk about an uncommon technique called 'bloodless surgery' that is slowly gaining popularity. It is worthwhile to know about the hazards of transfusion and the benefits that can be obtained by eliminating (or at least reducing) transfusion. Also, with the rising number of people opting for bloodless surgery and care, it will be informative to know about the strategies that one can apply to conserve blood.What Is Bloodless Surgery?
Bloodless surgery is also known as transfusion-free surgery. It is a technique that does not use any blood products or transfusions during a surgical procedure. This technique is usually used by doctors as an alternative for people who require surgery but can manage without blood transfusions. This form of surgery is mostly chosen by people for religious or personal reasons.Why Bloodless Surgery Is Not Common
In the lay man's terms, bloodless surgery involves screening for and treating postoperative anaemia. A multidisciplinary approach is used to proactively identify and treat postoperative anaemia . This procedure involves minimum diagnostic tests and also takes up meticulous surgical techniques that can aid in preventing blood loss.
Extensive studies have been done on the risks and benefits of blood transfusion following cardiac surgery. However, there is little consensus on an optimum transfusion trigger. Doctors who follow the traditional technique of blood transfusion post surgery advocate their opinion saying that transfusing blood increases the number of red blood cells and this, in turn, increases the oxygen-carrying capacity of the blood (although this theory has not been backed up by research). Studies have proven that worldwide there could be as many as two-thirds of all transfusions that might not actually be necessary.
Many medical professionals have been socialized to accept that blood loss is an unavoidable part of any major surgery and hence blood needs to be replaced through transfusions. Although great care is taken in reducing the risks of viral transmission during blood transfusions, yet there continues to exist risks that can be fatal.
It is important that healthcare providers understand strategies to reduce blood loss in patients. Blood transfusions can be avoided by taking precautionary measures to minimize blood loss . Continue reading to understand the medical techniques critical to reducing unnecessary blood loss.
Risks Of Blood Transfusion
The primary concern is the transmission of viral infections (such as HIV or hepatitis). Nevertheless, the medical community has minimized the risk of contracting HIV and hepatitis C by implementing nucleic acid testing. However, this is only the beginning.
Apart from viral infections, the major concern lies in the possibility of infectious prions being transmitted through blood transfusion. Prions are considered to be the cause of infectious diseases relating to the central nervous system. One such disease is a variant Creutzfeldt-Jacob disease (originated from the mutation that causes mad cow disease). Studies exist to show how a few people got infected with this after receiving a blood transfusion from donors .
Some of the most common noninfectious serious hazards of blood transfusion are as follows :
Studies have shown that mistransfusion is a common problem and there is about 1 case in every 10,000 transfused unit (the numbers could be higher as not all cases get reported). Errors can occur anytime- - at the time of collection of the specimen for type and crossmatch, in the lab, while labelling the blood or even at the bedside when the blood is being administered .
Another common complication is circulatory overload. Studies were conducted on two sets of people. The first group received a liberal transfusion of blood if their haemoglobin level dropped below 10 g/dL. The second group (conservative group) received blood only if their haemoglobin level dropped below 7 g/dL. The study results revealed that patients in the first group had significantly higher rates of morbidity from pulmonary and cardiac complications .
Medical centres also report several cases of immunosuppressive effects of blood transfusions . It is usually the sickest patients who receive blood transfusions and then face the effects of immune system depression for months or years.
Benefits Of Reducing Or Eliminating Blood Transfusions
It is a known fact that banked blood is a limited resource that does not come free of cost. Moreover, as more transfusion-transmitted disease related testing is underway, the costs are even going to go higher because of the decrease in the blood supply (due to increased identification of tainted blood). We also need to consider the indirect costs involved with treating complications related to blood transfusions (although this is difficult to quantify) .
When statistics were studied globally, it was found that hospitals that implemented bloodless medicinal programs showed a 16 per cent reduction in surgical costs and also a 17 per cent reduction in the overall hospital charges due to decreased duration of patient's stay . Reducing or eliminating blood transfusions also results in improved patient outcomes.Blood Conservation Strategies
There are several categories of blood conservation strategies.1. Preoperative strategies
Identification and management of anaemia are one of the most important strategies in bloodless surgery. Patients for whom bloodless surgery seems feasible should be evaluated for anaemia. In case the haemoglobin levels are low, the person should be treated for anaemia before the surgery. Building up the blood supply prior to the surgery makes it possible to avoid blood transfusion post surgery. Depending on the severity of anaemia and the waiting time permissible for the surgery, blood supply can be built up through diet, iron supplements or with the use of erythropoietin (can be administered subcutaneously or intravenously).
Autologous blood donation could be a preoperative strategy too, but it is not possible in all cases. In the case of cardiac surgery patients, their condition is not likely to be satisfactory in terms of the blood donation criteria. In spite of being autologous blood, it still carries the risk of bacterial infection.2. Intraoperative strategies
Surgical, anaesthetic and pharmacological techniques are put into use to minimize blood loss during surgery. One such technique is acute normovolemic hemodilution . This involves removing several units of blood and then storing it in the operating room prior to surgery. The remaining blood of the patient is then diluted with crystalloids or colloids. This is done to maintain a normal circulating blood volume. This diluted blood, when lost during surgery, would have lesser number of red blood cells and lowered levels of clotting factors. The stored fresh blood is then readministered post surgery (in some case, during the surgery itself)
Several pharmacologic agents are used to reduce intraoperative blood loss- - such as aprotinin, antifibrinolytic aminocaproic acid and desmopressin .
Minimizing blood loss from phlebotomy is another strategy. This involves identifying the importance and necessity of each blood test done and also the possibility of being able to consolidate blood tests.3. Lowering the traditional transfusion trigger
Reevaluation of traditional transfusion triggers continues to remain the most controversial topic in blood management . Until some years ago, a haemoglobin level of 10 g/dL was believed to be the accepted point at which blood transfusions should be initiated. However, even post continuous research, there is little consensus on the ideal transfusion trigger.
Experts cite multiple factors that could come into play here- - these being the patient's age, cardiopulmonary status and comorbidities. Also, there is a need to individualize the transfusion point for each patient . At present, the agreed upon the optimal point for transfusion is the lowest level of haemoglobin that is necessary to meet an individual patient's tissue oxygen demands (this is determined based on the patient's health condition).
Bangalore-based Doctor Performs Bloodless Open Heart Surgery Successfully
A 39-year-old woman, belonging to the Jehovah's Witness Faith (does not allow followers to undergo blood transfusions), required open-heart surgery. When she approached the doctors of one of the most renowned hospitals in the city, the doctors decided that they would perform a bloodless surgery. According to the doctor who led the team and successfully completed the bloodless cardiac surgery, people of this faith always opt for bloodless surgery and it is surely a blessing in disguise as it helps in quick recovery of the patient as well .
He also went on to say that patients who belong to this particular religious background often look out for doctors who are experienced with bloodless surgeries, so that they can seek the perfect treatment while holding onto their faith. In the case of the 39-year-old woman, once the surgery was performed successfully, she was put on medications to help her maintain the haemoglobin levels.On A Final Note...
It is time that patients take an active role in their medical decision making. It is important that one gets to know the potential risks of blood transfusion. Even today, many people deny receiving allogeneic blood (blood from donors). However, it is also important to know that even if the blood is received from someone you know personally, there still exists a high risk of receiving blood that can lead to fatal illnesses.
A patient can always request his or her doctor to consider all possible alternative options first before carrying out blood transfusion. Studies cite bloodless medicine and surgery as the 'criterion standard of care' . As bloodless techniques are being taught in medical institutes, it will most likely become the rule rather than an exception in the near future.