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The best evidence exists for the treatment of septic shock in adults and as the pathophysiology appears similar in children and other types of shock treatment this has been extrapolated to these areas. Management may include securing the airway via intubation if necessary to decrease the work of breathing and for guarding against respiratory arrest. Oxygen supplementation, intravenous fluids, passive leg raising (not Trendelenburg position) should be started and blood transfusions added if blood loss is severe. It is important to keep the person warm as well as adequately manage pain and anxiety as these can increase oxygen consumption.
Aggressive intravenous fluids are recommended in most types of shock (e.g. 1–2 liter normal saline bolus over 10 minutes or 20 ml/kg in a child) which is usually instituted as the person is being further evaluated. Which intravenous fluid is superior, colloids or crystalloids, remains undetermined. Thus as crystalloids are less expensive they are recommended. If the person remains in shock after initial resuscitation packed red blood cells should be administered to keep the hemoglobin greater than 100 g/l.
For those with haemorrhagic shock the current evidence supports limiting the use of fluids for penetrating thorax and abdominal injuries allowing mild hypotension to persist (known as permissive hypotension). Targets include a mean arterial pressure of 60 mmHg, a systolic blood pressure of 70–90 mmHg, or until their adequate mentation and peripheral pulses.
The choice of fluids for resuscitation remains an area of research, the Surviving Sepsis Campaign an international consortium of experts, did not find adequate evidence to support the superiority crystalloid fluids versus colloid fluids. Drugs such as, pyridoxalated hemoglobin polyoxyethylene, which scavenge nitric oxide from the blood have been investigated. As well as methylene blue which may inhibit the nitric oxide-cyclic guanosine monophosphate (NO-cGMP) pathway which has been suggested to play a significant role in distributive shock.
Septic shock is associated with significant mortality and is the leading non cardiac cause of death in intensive care units (ICUs).
Because lowered blood pressure in septic shock contributes to poor perfusion, fluid resuscitation is an initial treatment to increase blood volume. Crystalloids such as normal saline and lactated Ringer's solution are recommended as the initial fluid of choice, while the use of colloid solutions such as hydroxyethyl starch have not shown any advantage or decrease in mortality. When large quantities of fluids are given, administering albumin has shown some benefit.
Treatment primarily consists of the following:
1. Giving intravenous fluids
2. Early antibiotic administration
3. Early goal directed therapy
4. Rapid source identification and control
5. Support of major organ dysfunction
6. High fever
Emergency oxygen should be immediately employed to increase the efficiency of the patient's remaining blood supply. This intervention can be life-saving.
The use of intravenous fluids (IVs) may help compensate for lost fluid volume, but IV fluids cannot carry oxygen in the way that blood can; however, blood substitutes are being developed which can. Infusion of colloid or crystalloid IV fluids will also dilute clotting factors within the blood, increasing the risk of bleeding. It is current best practice to allow permissive hypotension in patients suffering from hypovolemic shock, both to ensure clotting factors are not overly diluted and also to stop blood pressure being artificially raised to a point where it "blows off" clots that have formed.
Fluid replacement is beneficial in hypovolemia of stage 2, and is necessary in stage 3 and 4. See also the discussion of shock and the importance of treating reversible shock while it can still be countered.
For a patient presenting with hypovolemic shock in hospital the following investigations would be carried out:
- Blood tests: U+Es/Chem7, full blood count, glucose, blood type and screen
- Central venous catheter or blood pressure
- Arterial line or arterial blood gases
- Urine output measurements (via urinary catheter)
- Blood pressure
- SpO2 Oxygen saturations
The following interventions would be carried out:
- IV access
- Oxygen as required
- Surgical repair at sites of hemorrhage
- Inotrope therapy (Dopamine, Noradrenaline) which increase the contractility of the heart muscle
- Fresh frozen plasma or whole blood
Vasopressors (like Norepinephrine, Dobutamine) should generally be avoided, as they may result in further tissue ischemia and don't correct the primary problem. Fluids are the preferred choice of therapy.
The treatment for hypotension depends on its cause. Chronic hypotension rarely exists as more than a symptom. Asymptomatic hypotension in healthy people usually does not require treatment. Adding electrolytes to a diet can relieve symptoms of mild hypotension. A morning dose of caffeine can also be effective. In mild cases, where the patient is still responsive, laying the person in dorsal decubitus (lying on the back) position and lifting the legs increases venous return, thus making more blood available to critical organs in the chest and head. The Trendelenburg position, though used historically, is no longer recommended.
Hypotensive shock treatment always follows the first four following steps. Outcomes, in terms of mortality, are directly linked to the speed that hypotension is corrected. Still-debated methods are in parentheses, as are benchmarks for evaluating progress in correcting hypotension. A study on septic shock provided the delineation of these general principles. However, since it focuses on hypotension due to infection, it is not applicable to all forms of severe hypotension.
1. Volume resuscitation (usually with crystalloid)
2. Blood pressure support with a vasopressor (all seem equivalent with respect to risk of death, with norepinephrine possibly better than dopamine). Trying to achieve a mean arterial pressure (MAP) of greater than 70 mmHg does not appear to result in better outcomes than trying to achieve a MAP of greater than 65 mm Hg in adults.
3. Ensure adequate tissue perfusion (maintain SvO2 >70 with use of blood or dobutamine)
4. Address the underlying problem (i.e., antibiotic for infection, stent or CABG (coronary artery bypass graft surgery) for infarction, steroids for adrenal insufficiency, etc...)
The best way to determine if a person will benefit from fluids is by doing a passive leg raise followed by measuring the output from the heart.
Medium-term (and less well-demonstrated) treatments of hypotension include:
- Blood sugar control (80–150 by one study)
- Early nutrition (by mouth or by tube to prevent ileus)
- Steroid support
With proper treatment, people usually recover in two to three weeks. The condition can, however, be fatal within hours.
Neurogenic shock is a distributive type of shock resulting in low blood pressure, occasionally with a slowed heart rate, that is attributed to the disruption of the autonomic pathways within the spinal cord. It can occur after damage to the central nervous system such as spinal cord injury. Low blood pressure occurs due to decreased systemic vascular resistance resulting in pooling of blood within the extremities lacking sympathetic tone. The slowed heart rate results from unopposed vagal activity and has been found to be exacerbated by hypoxia and endobronchial suction.
Neurogenic shock can be a potentially devastating complication, leading to organ dysfunction and death if not promptly recognized and treated. It is not to be confused with spinal shock, which is not circulatory in nature.
The severity of this disease frequently warrants hospitalization. Admission to the intensive care unit is often necessary for supportive care (for aggressive fluid management, ventilation, renal replacement therapy and inotropic support), particularly in the case of multiple organ failure. The source of infection should be removed or drained if possible: abscesses and collections should be drained. Anyone wearing a tampon at the onset of symptoms should remove it immediately. Outcomes are poorer in patients who do not have the source of infection removed.
Antibiotic treatment should cover both "S. pyogenes" and "S. aureus". This may include a combination of cephalosporins, penicillins or vancomycin. The addition of clindamycin or gentamicin reduces toxin production and mortality.
A circulatory collapse is defined as a general or specific failure of the circulation, either cardiac or peripheral in nature.
Although the mechanisms, causes and clinical syndromes are different the pathogenesis is the same, the circulatory system fails to maintain the supply of oxygen and other nutrients to the tissues and to remove the carbon dioxide and other metabolites from them. The failure may be hypovolemic, distributive.
A common cause of this could be shock or trauma from injury or surgery.
Surgical shock is the shock to the circulation resulting from surgery. It is commonly due to a loss of blood which results in insufficient blood volume.
Neurogenic shock can result from severe central nervous system damage (brain injury, cervical or high thoracic spinal cord). In more simple terms: the trauma causes a sudden loss of background sympathetic stimulation to the blood vessels. This causes them to relax (vasodilation) resulting in a sudden decrease in blood pressure (secondary to a decrease in peripheral vascular resistance).
Neurogenic shock results from damage to the spinal cord above the level of the 6th thoracic vertebra. It is found in about half of people who suffer spinal cord injury within the first 24 hours, and usually doesn't go away for one to three weeks.
Depending on the type of cardiogenic shock, treatment involves infusion of fluids, or in shock refractory to fluids, inotropic medications. In case of an abnormal heart rhythm several anti-arrhythmic agents may be administered, e.g. adenosine.
Positive inotropic agents (such as dobutamine or milrinone), which enhance the heart's pumping capabilities, are used to improve the contractility and correct the low blood pressure. Should that not suffice an intra-aortic balloon pump (which reduces workload for the heart, and improves perfusion of the coronary arteries) or a left ventricular assist device (which augments the pump-function of the heart) can be considered. Finally, as a last resort, if the person is stable enough and otherwise qualifies, heart transplantation, or if not eligible an artificial heart, can be placed. These invasive measures are important tools- more than 50% of patients who do not die immediately due to cardiac arrest from a lethal abnormal heart rhythm and live to reach the hospital (who have usually suffered a severe acute myocardial infarction, which in itself still has a relatively high mortality rate), die within the first 24 hours. The mortality rate for those still living at time of admission who suffer complications (among others, cardiac arrest or further abnormal heart rhythms, heart failure, cardiac tamponade, a ruptured or dissecting aneurysm, or another heart attack) from cardiogenic shock is even worse around 85%, especially without drastic measures such as ventricular assist devices or transplantation.
Cardiogenic shock may be treated with intravenous dobutamine, which acts on β receptors of the heart leading to increased contractility and heart rate.
A "general failure" is one that occurs across a wide range of locations in the body, such as systemic shock after the loss of a large amount of blood collapsing all the circulatory systems in the legs. A "specific failure" can be traced to a particular point, such as a clot.
Cardiac circulatory collapse affects the vessels of the heart such as the aorta and is almost always fatal. It is sometimes referred to as "acute" circulatory failure.
Peripheral circulatory collapse involves outlying arteries and veins in the body and can result in gangrene, organ failure or other serious complications. This form is sometimes called "peripheral vascular failure", "shock" or "peripheral vascular shutdown".
A milder or preliminary form of circulatory collapse is circulatory insufficiency.
Not required for physiologic sinus tachycardia. Underlying causes are treated if present.
Acute myocardial infarction. Sinus tachycardia can present in more than a third of the patients with AMI but this usually decreases over time. Patients with sustained sinus tachycardia reflects a larger infarct that are more anterior with prominent left ventricular dysfunction, associated with high mortality and morbidity. Tachycardia in the presence of AMI can reduce coronary blood flow and increase myocardial oxygen demand, aggravating the situation. Beta blockers can be used to slow the rate, but most patients are usually already treated with beta blockers as a routine regimen for AMI.
Practically, many studies showed that there is no need for any treatment.
IST and POTS. Beta blockers are useful if the cause is sympathetic overactivity. If the cause is due to decreased vagal activity, it is usually hard to treat and one may consider radiofrequency catheter ablation.
Early recognition and focused management may improve the outcomes in sepsis. Current professional recommendations include a number of actions ("bundles") to be followed as soon as possible after diagnosis. Within the first three hours someone with sepsis should have received antibiotics and, intravenous fluids if there is evidence of either low blood pressure or other evidence for inadequate blood supply to organs (as evidenced by a raised level of lactate); blood cultures also should be obtained within this time period. After six hours the blood pressure should be adequate, close monitoring of blood pressure and blood supply to organs should be in place, and the lactate should be measured again if initially, it was raised. A related bundle, the "Sepsis Six", is in widespread use in the United Kingdom; this requires the administration of antibiotics within an hour of recognition, blood cultures, lactate and hemoglobin determination, urine output monitoring, high-flow oxygen, and intravenous fluids.
Apart from the timely administration of fluids and antibiotics, the management of sepsis also involves surgical drainage of infected fluid collections and appropriate support for organ dysfunction. This may include hemodialysis in kidney failure, mechanical ventilation in lung dysfunction, transfusion of blood products, and drug and fluid therapy for circulatory failure. Ensuring adequate nutrition—preferably by enteral feeding, but if necessary, by parenteral nutrition—is important during prolonged illness. In those with high blood sugar levels, insulin to bring it down to 7.8–10 mmol/L (140–180 mg/dL) is recommended with lower levels potentially worsening outcomes. Medication to prevent deep vein thrombosis and gastric ulcers also may be used.
Cardiogenic shock is a life-threatening medical condition resulting from an inadequate circulation of blood due to primary failure of the ventricles of the heart to function effectively. Signs of inadequate blood flow to the body's organs include low urine production (<30 mL/hour), cool arms and legs, and altered level of consciousness. It may lead to cardiac arrest, which is an abrupt stopping of cardiac pump function.
As this is a type of circulatory shock, there is insufficient blood flow and oxygen supply for biological tissues to meet the metabolic demands for oxygen and nutrients. Cardiogenic shock is defined by sustained low blood pressure with tissue hypoperfusion despite adequate left ventricular filling pressure.
Treatment of cardiogenic shock depends on the cause. If cardiogenic shock is due to a heart attack, attempts to open the heart's arteries may help. An intra-aortic balloon pump or left ventricular assist device may improve matters until this can be done. Medications that improve the heart's ability to contract (positive inotropes) may help; however, it is unclear which is best. Norepinephrine may be better if the blood pressure is very low whereas dopamine or dobutamine may be more useful if only slightly low. Cardiogenic shock is a condition that is difficult to fully reverse even with an early diagnosis. With that being said, early initiation of mechanical circulatory support, early percutaneous coronary intervention, inotropes, and heart transplantation may improved outcomes.
Treating fever in people with sepsis does not affect outcomes.
Monoclonal and polyclonal preparations of intravenous immunoglobulin (IVIG) do not lower the rate of death in newborns and adults with sepsis. Evidence for the use of IgM-enriched polyclonal preparations of IVIG is inconsistent. A 2012 Cochrane review concluded that N-acetylcysteine does not reduce mortality in those with SIRS or sepsis and may even be harmful.
Recombinant activated protein C (drotrecogin alpha) was originally introduced for severe sepsis (as identified by a high APACHE II score), where it was thought to confer a survival benefit. However, subsequent studies showed that it increased adverse events—bleeding risk in particular—and did not decrease mortality. It was removed from sale in 2011. Another medication known as eritoran also has not shown benefit.
A domestic power supply voltage (110 or 230 V), 50 or 60 Hz alternating current (AC) through the chest for a fraction of a second may induce ventricular fibrillation at currents as low as . With direct current (DC), 300 to 500 mA is required. If the current has a direct pathway to the heart (e.g., via a cardiac catheter or other kind of electrode), a much lower current of less than 1 mA (AC or DC) can cause fibrillation. If not immediately treated by defibrillation, fibrillation is usually lethal because all of the heart muscle fibres move independently instead of in the coordinated pulses needed to pump blood and maintain circulation. Above 200 mA, muscle contractions are so strong that the heart muscles cannot move at all, but these conditions prevent fibrillation.
Electrical injury is a physiological reaction caused by electric current passing through the (human) body. Electric shock occurs upon contact of a (human) body part with any source of electricity that causes a sufficient magnitude of current to pass through the victim's flesh, viscera or hair. Physical contact with energized wiring or devices is the most common cause of an electric shock. In cases of exposure to high voltages, such as on a power transmission tower, physical contact with energized wiring or objects may not be necessary to cause electric shock, as the voltage may be sufficient to "jump" the air gap between the electrical device and the victim.
The injury related to electric shock depends on the magnitude of the current. Very small currents may be imperceptible or produce a light tingling sensation. A shock caused by low current that would normally be harmless could startle an individual and cause injury due to suddenly jerking away from the source of electricity, resulting in one striking a stationary object, dropping an object being held or falling. Stronger currents may cause some degree of discomfort or pain, while more intense currents may induce involuntary muscle contractions, preventing the victim from breaking free of the source of electricity. Still larger currents usually result in tissue damage and may trigger fibrillation of the heart or cardiac arrest, any of which may ultimately be fatal. If death results from an electric shock the cause of death is generally referred to as electrocution.
Hematemesis is treated as a medical emergency. The most vital distinction is whether there is blood loss sufficient to cause shock.