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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.
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
The main goals of treatment in distributive shock are to reverse the underlying cause and achieve hemodynamic stabilization. Immediate treatment involves fluid resuscitation and the use of vasoactive drugs, both vasopressors and inotropes. Hydrocortisone is used for patients whose hypotension does not respond to fluid resuscitation and vasopressors. Opening and keeping open the microcirculation is a consideration in the treatment of distributive shock, as a result limiting the use of vasopressors has been suggested. Control of inflammation, vascular function and coagulation to correct pathological differences in blood flow and microvascular shunting has been pointed to as a potentially important adjunct goal in the treatment of distributive shock.
Patients with septic shock are treated with antimicrobial drugs to treat the causative infection. Some sources of infection require surgical intervention including necrotizing fasciitis, cholangitis, abscess, intestinal ischemia, or infected medical devices.
Anaphylactic shock is treated with epinephrine.
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.
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.
OSHA found that up to 80 percent of its electrical injuries involve thermal burns due to arcing faults. The arc flash in an electrical fault produces the same type of light radiation from which electric welders protect themselves using face shields with dark glass, heavy leather gloves, and full-coverage clothing. The heat produced may cause severe burns, especially on unprotected flesh. The arc blast produced by vaporizing metallic components can break bones and damage internal organs. The degree of hazard present at a particular location can be determined by a detailed analysis of the electrical system, and appropriate protection worn if the electrical work must be performed with the electricity on.
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.
With proper treatment, people usually recover in two to three weeks. The condition can, however, be fatal within hours.
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.
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.
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.
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.
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.
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.
Hypovolemia is a state of decreased blood volume; more specifically, decrease in volume of blood plasma. It is thus the intravascular component of volume contraction (or loss of blood volume due to things such as bleeding or dehydration), but, as it also is the most essential one, "hypovolemia" and volume contraction are sometimes used synonymously.
Hypovolemia is characterized by sodium depletion (salt depletion) and thus differs from dehydration, which is defined as excessive loss of body water.
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.
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.
Initial treatment given will usually be supportive in nature, for example administration of oxygen, and monitoring. There is little care that can be provided pre-hospital other than general treatment for shock. Some teams have performed an emergency thoracotomy to release clotting in the pericardium caused by a penetrating chest injury.
Prompt diagnosis and treatment is the key to survival with tamponade. Some pre-hospital providers will have facilities to provide pericardiocentesis, which can be life-saving. If the patient has already suffered a cardiac arrest, pericardiocentesis alone cannot ensure survival, and so rapid evacuation to a hospital is usually the more appropriate course of action.
Sinus tachycardia is usually a response to normal physiological situations, such as exercise and an increased sympathetic tone with increased catecholamine release—stress, fright, flight, anger. Other causes include:
- Pain
- Fever
- Anxiety
- Dehydration
- Malignant hyperthermia
- Hypovolemia with hypotension and shock
- Anemia
- Heart failure
- Hyperthyroidism
- Mercury poisoning
- Kawasaki disease
- Pheochromocytoma
- Sepsis
- Pulmonary embolism
- Acute coronary ischemia and myocardial infarction
- Chronic obstructive pulmonary disease
- Hypoxia
- Intake of stimulants such as caffeine, theophylline, nicotine, cocaine, or amphetamines
- Hyperdynamic circulation
- Electric shock
- Drug withdrawal
- Porphyria
- Acute inflammatory demyelinating polyradiculoneuropathy
- Postural orthostatic tachycardia syndrome
Myocardial infarction complications may occur immediately following a heart attack (in the acute phase), or may need time to develop (a chronic problem). After an infarction, an obvious complication is a second infarction, which may occur in the domain of another atherosclerotic coronary artery, or in the same zone if there are any live cells left in the infarct.
Initial management in hospital is by pericardiocentesis. This involves the insertion of a needle through the skin and into the pericardium and aspirating fluid under ultrasound guidance preferably. This can be done laterally through the intercostal spaces, usually the fifth, or as a subxiphoid approach. A left parasternal approach begins 3 to 5 cm left of the sternum to avoid the left internal mammary artery, in the 5th intercostal space. Often, a cannula is left in place during resuscitation following initial drainage so that the procedure can be performed again if the need arises. If facilities are available, an emergency pericardial window may be performed instead, during which the pericardium is cut open to allow fluid to drain. Following stabilization of the patient, surgery is provided to seal the source of the bleed and mend the pericardium.
In people following heart surgery the nurses monitor the amount of chest tube drainage. If the drainage volume drops off, and the blood pressure goes down, this can suggest tamponade due to chest tube clogging. In that case, the patient is taken back to the operating room for an emergency reoperation.
If aggressive treatment is offered immediately and no complications arise (shock, AMI or arrhythmia, heart failure, aneurysm, carditis, embolism, or rupture), or they are dealt with quickly and fully contained, then adequate survival is still a distinct possibility.
A complication that may occur in the acute setting soon after a myocardial infarction or in the weeks following is cardiogenic shock. Cardiogenic shock is defined as a hemodynamic state in which the heart cannot produce enough of a cardiac output to supply an adequate amount of oxygenated blood to the tissues of the body.
While the data on performing interventions on individuals with cardiogenic shock is sparse, trial data suggests a long-term mortality benefit in undergoing revascularization if the individual is less than 75 years old and if the onset of the acute myocardial infarction is less than 36 hours and the onset of cardiogenic shock is less than 18 hours. If the patient with cardiogenic shock is not going to be revascularized, aggressive hemodynamic support is warranted, with insertion of an intra-aortic balloon pump if not contraindicated. If diagnostic coronary angiography does not reveal a culprit blockage that is the cause of the cardiogenic shock, the prognosis is poor.