blood poisoning

Blood poisoning: description

Blood poisoning is not caused, as is often assumed, by the presence of pathogens in the blood, but by the body’s response to it. Causes of blood poisoning are usually bacteria. In rare cases, the blood poisoning is triggered by viruses, protozoa or fungi (Candida). The immune system tries to defend itself against the pathogens, but this fight not only harms the invaders, but also the body itself. Sepsis is a potentially life-threatening disease and should be treated consistently as quickly as possible. The sepsis definition differs depending on the severity of the blood poisoning.

Forms of sepsis

If you find bacteria in the blood (bacteremia), that does not mean that you have blood poisoning. Such a find does not have a disease value per se. Small amounts of bacteria, for example, penetrate the bloodstream during tooth brushing due to micro injuries in the gums, without triggering a body-wide inflammatory reaction. The healthy body’s immune system can easily cope with such small amounts of pathogens. Only when this is no longer the case and you get sick through this fight, it is called a sepsis. The main signs of blood poisoning are the following symptoms in adults:

• a deviation of the body temperature upwards or downwards ( 38 ° C)
• an increased heart rate (> 90 beats / minute)
• an increased respiratory rate (> 20 breaths / min)
• a deviation in the number of white blood cells in the blood (leukocytes) ( 12.000 / μL)

If these points are met, one speaks of one SIRS (Systemic Inflammatory Response Syndrome), but not yet from sepsis.

SIRS (Systemic Inflammatory Response Syndrome)

Learn more about triggers and events in a systemic inflammatory reaction of the body in the article SIRS.

The criteria for a blood poisoning (Sepsis) are met as soon as an infectious cause of the body reaction can be detected. If organs are impaired in their function, one speaks of the sepsis definition of one severe sepsis, Causes for the failure of organs can be blood clots, a high blood pressure or even reactions to endogenous messenger substances, which actually serve the fight against the pathogens. The risk of dying from severe sepsis is about 47 percent.

If blood pressure can no longer be maintained at a sufficient level due to this inflammatory reaction, this is called a “septic shock“. This terminal stage of blood poisoning consequently jeopardizes the blood supply of vital organs and leads to death in more than half of those affected.

Septic shock

In the article Septic Shock you will learn more about the risks in the final stages of blood poisoning.

neonatal sepsis

A special case of blood poisoning is the so-called neonatal sepsis, It describes a blood poisoning in babies in the first month of life. There are typically two types, depending on how fast sepsis occurs after birth. The so-called early onset sepsis, in which the pathogen was most likely transmitted during the birthing process by the mother, occurs within the first four days of life. Afterwards one speaks of a late sepsis (late onset sepsis). However, recent studies show that this subdivision has no significant relevance to the treatment.

The sepsis criteria of neonatal sepsis are more difficult to detect than in adult patients. Newborn sepsis is feared for its fulminant course. In babies, blood poisoning can become a life-threatening disease much faster. As a rule, the mother is examined before birth for bacteria in her vagina, which could potentially endanger the child. Due to this investigation and strict hygiene regulations, the incidence of neonatal sepsis cases in the industrialized nations has been drastically reduced in the last decade.

Blood poisoning: symptoms

Everything important for the typical signs of sepsis can be read in the article “Blood poisoning – Symptoms”.

Blood poisoning: causes and risk factors

In principle, any infection can lead to sepsis (blood poisoning), but it does not have to. Targeted prevention of blood poisoning is not possible. In principle, however, it is advisable that any infection – even if it initially seems harmless – to be treated early by a doctor.

At the onset of sepsis (blood poisoning) is a locally limited infection, whose causes are mostly bacteria, sometimes viruses, fungi (Candida sepsis) or so-called protozoa (unicellular organisms). The immune system starts defense reactions against the intruders in the form of an inflammation: The blood circulation of the relevant tissue is increased, the permeability of the blood vessels is increased. Thus, large amounts of white blood cells (leukocytes) can get to the site of infection and enter the tissue, where they eliminate the pathogens and destroyed cells.

However, the concentrated immunity of the immune system is sometimes insufficient to limit and eventually eliminate the infection at its point of origin. The pathogens then gain the upper hand: It comes to the entry of the pathogens and their toxins in the bloodstream. According to the definition of sepsis in this case one does not speak of a blood poisoning, but for the time being of a bacteremia (bacteria in the blood).

Dissolve these substances now a body-wide inflammatory response, it is called the typical sepsis course. The symptoms of sepsis are related to this body-wide fight between the immune system and pathogens. The vessels in the whole body expand, leading to a fall in blood pressure, signs of inflammation in the blood rise dramatically, the heart and the lungs try to compensate for the lack of blood flow back and its accumulation with oxygen through increased work, causing respiratory and heart rate increase.

Due to the altered blood flow and damage to vessels and tissues by the pathogens and the immune system, the blood clots faster. Based on the sepsis criteria one speaks of one severe sepsisas soon as organs are impaired in their function by small clogged vessels (thrombi), or other harmful substances.

If the pumping power of the heart is no longer sufficient to transport enough blood to the vital organs, one speaks in addition of one septic shock.

Risk groups: sepsis

Causes of blood poisoning can in principle be any localized infections (such as pneumonia or urinary tract infections). Not infrequently, hospital infections (nosocomial) are the cause of sepsis. Particularly high is the risk of blood poisoning in:

• very young (newborn) as well as very old people
• a weakened immune system (for example due to cancer chemotherapy or high dose cortisone therapy for rheumatism or respiratory disease)
• Wounds or injuries (e.g., large burns)
• Certain treatments and examinations (e.g., catheters in blood vessels, bladder catheters, wound drains)
• Addictions (e.g., alcoholism, drug addiction)
• Genetic predisposition to sepsis

Blood poisoning: examinations and diagnosis

If there is a suspicion of blood poisoning, the following sepsis criteria are checked:

• Existence of a infection, e.g. by microbiological detection of pathogens in a patient sample (blood sample, urine sample, wound swab) or pneumonia using an X-ray
• Fever (at least 38 degrees Celsius) or low temperature (36 degrees Celsius or less), measured with a thermometer in the rectum (rectal), in a blood vessel (intravascular), or in the urinary bladder (intravesical)
• Heart rate at least 90 beats per minute (tachycardia)
• certain changes in the large blood count: leukocyte count (white blood cells) either increased (≥ 12,000 / μL) or decreased (≤ 4,000 / μL) or ≥ ten percent immature neutrophils (subgroup of white blood cells)
• Increase in inflammatory parameters CRP (C-reactive protein) or pro-calcitonin
• faulty organ function, for example in the brain (limited attention, disorientation, restlessness, confusion, delirium, coma, loss of sensation in one part of the body, limitation of movement), liver (liver enzymes and bilirubin increased, skin color changed), kidney (decreased urine excretion, Blood pH decreases, creatinine level increases), lung (decreasing oxygen and increased carbon dioxide in, blood)
• Coagulation disorders, decrease in the number of platelets (thrombocytes)

Once the restriction of organ function is detected, it is called a severe sepsis. This also applies if the sepsis causes have not yet been clarified. If a critical fall in blood pressure occurs, it is called a septic shock.

Blood poisoning: treatment

A prerequisite for a successful therapy of sepsis is the treatment of the underlying disease – ie the infection that has led to blood poisoning. It can be done surgically or by medication. The treatment of blood poisoning thus always begins with the search for the source of infection. For example, an inflamed cecum may be the trigger or an infected joint prosthesis. Even seemingly trivial things like a vascular access to the arm, or a urine catheter can cause blood poisoning.

Most commonly, the focus is on the lungs, abdomen, urinary tract, skin, bones and joints, teeth, or the central nervous system (e.g., meningitis, encephalitis). Foreign material in the body may also be the seat of the infection center, for example screws and plates used in bone surgery or the “spiral” (IUD) for contraception.

If possible, this starting point of sepsis is eliminated as quickly as possible – in the jargon this procedure is called “rehabilitation”. In about 20 percent of sepsis patients, however, the origin of the infection can not be located.

Treatment of simple sepsis

In a simple sepsis, a stay in the intensive care unit is usually not necessary. Here it is sufficient to eliminate the source of infection and to start a therapy with antibiotics, since most bacteria are responsible for a blood poisoning. If it is a fungal (Candida sepsis), viral or parasitic infection, it must be treated accordingly.

Treatment of severe sepsis

In severe blood poisoning, in addition to the elimination of the source of infection and antibiotic therapy and the limited organ functions must be considered. In this more dangerous sepsis course, the equipment of an intensive care unit is always necessary.

The pathogen should definitely be named and analyzed to be able to select the best therapy. Depending on the pathogen, you can then select, for example, an antibiotic or an antifungal (antimycotic).

Additional measures of sepsis treatment in the intensive care unit include:

• the replacement of liquid by infusion and possibly nutrient solutions when patients can no longer eat. The latter can also be done by probe through the nose into the stomach (gastric tube)
• If necessary, the replacement of blood cells and plasma by transfusion
• the support of the function of affected organs, for example by artificial respiration in the case of (imminent) respiratory failure or dialysis, which relieves the kidney of the task of filtering blood.
• the gift of painkillers and sedatives
• If necessary, a blood sugar-lowering insulin therapy, as in some patients with sepsis, the blood sugar level rises
• Preventing a so-called stress ulcer – a stomach ulcer in the stomach or duodenum that may cause bleeding due to body stress. In particular, proton pump inhibitors or histamine-2 receptor blockers are used.
• the anticoagulant medication used to prevent blood clots (thrombosis) that can form throughout the body in the event of severe sepsis

Newer therapies with artificial antibodies (immunoglobulins) can be considered in severe cases. However, there is still a lack of knowledge as to which antibodies are most effective in which form of sepsis. For this reason, this treatment of blood poisoning is not yet recommended as a standard.

Treatment of septic shock

In addition to the above-mentioned interventions, there is the additional problem with septic shock that sufficient blood pressure and the pumping function of the heart must be ensured in order to continue to provide adequate blood supply to all organs.

So-called vasopressor (vasoconstrictor) substances increase the blood pressure when it has dropped due to a septic shock. (see sepsis criteria in the section “Symptoms”).

In addition, attempts are made to keep the vessels in a filled state by high infusion of liquid by infusion, because by their Weitstellung much blood in the periphery (arms, legs, tissues) and in the tissue sagging, and does not flow back fast enough to the heart. Usually at this time the patient must also be artificially ventilated.

Blood poisoning: disease course and prognosis

The course of a blood poisoning is usually always the same: Bacteria enter the bloodstream from any point in the body and spread through the bloodstream (bacteremia). If the body can not limit the infection, sepsis will occur. Without treatment, the fight against the pathogens of blood poisoning is becoming more and more widespread, until eventually damage to vessels and organs occurs (severe sepsis). The rate of progression depends on the causative agent, the age of the patient and the performance of his immune system.

Further sepsis may lead to cardiovascular failure. Then the circulation of vital organs is no longer guaranteed, and one speaks of the septic shock. The sooner you start treatment, the better the chances of being completely healed. Organ damage often lifelong damage – for example, a limited or failed kidney function, which makes a lifelong dialysis (blood washing) necessary.

In some patients, the blood poisoning can not be successfully treated and the sepsis leads to death. Roughly one can say that the risk of death of a sepsis increases by about one percent per hour, in which the person concerned is not adequately treated. After one day without treatment, the risk is already 24 percent. In severe sepsis with organ damage already 47 percent of patients do not survive the disease. In a septic shock, it is even about 60 percent die from circulatory failure due to blood poisoning.

Danger of consequential damage

Many patients also suffer from long-term sequelae of blood poisoning, such as nerve damage (polyneuropathy), muscle weakness or post-traumatic stress, as well as depression after discharge from hospital. (microscopic nerve damage)

The best way to avoid the consequences of blood poisoning is if affected persons inform the doctor at an early stage. This applies in particular to people who are housed in hospitals or care facilities for immunocompromised and freshly operated patients. These groups of patients should inform their doctor immediately in case of fever, chills, shortness of breath and / or dizziness.

Precautions (prevention) are an important topic, especially in hospitals. Due to hygiene measures, good wound care, and consistent protection of immunocompromised patients can in many cases the emergence of a blood poisoning be avoided.