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Vasopressors may be used if blood pressure does not improve with fluids. There is no evidence of substantial superiority of one vasopressor over another; however, using dopamine leads to an increased risk of arrythmia when compared with norepinephrine. Vasopressors have not been found to improve outcomes when used for hemorrhagic shock from trauma but may be of use in neurogenic shock. Activated protein C (Xigris) while once aggressively promoted for the management of septic shock has been found not to improve survival and is associated with a number of complications. Xigris was withdrawn from the market in 2011, and clinical trials were discontinued. The use of sodium bicarbonate is controversial as it has not been shown to improve outcomes. If used at all it should only be considered if the pH is less than 7.0.
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 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.
Among the choices for vasopressors, norepinephrine is superior to dopamine in septic shock. Norepinephrine is the preferred vasopressor, while epinephrine may be added to norepinephrine when needed. Low-dose vasopressin also may be used as an addition to norepinephrine, but is not recommended as a first-line treatment. Dopamine may cause rapid heart rate and arrhythmias, and is only recommended in combination with norepinephrine in those with slow heart rate and low risk of arrhythmia. In the initial treatment of low blood pressure in septic shock, the goal of vasopressor treatment is a mean arterial pressure (MAP) of 65 mm Hg. In 2017, the FDA approved angiotensin II injection for intravenous infusion to increase blood pressure in adults with septic or other distributive shock.
Septic shock is associated with significant mortality and is the leading non cardiac cause of death in intensive care units (ICUs).
Treatment guidelines call for the administration of broad-spectrum antibiotics within the first hour following recognition of septic shock. Prompt antimicrobial therapy is important, as risk of dying increases by approximately 10% for every hour of delay in receiving antibiotics. Time constraints do not allow the culture, identification, and testing for antibiotic sensitivity of the specific microorganism responsible for the infection. Therefore, combination antimicrobial therapy, which covers a wide range of potential causative organisms, is tied to better outcomes.
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.
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
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.
Electric shock is also used as a medical therapy, under carefully controlled conditions:
- Electroconvulsive therapy or ECT is a psychiatric therapy for mental illness. The objective of the therapy is to induce a seizure for therapeutic effect. There is no conscious sensation of the electric shock because of the anesthesia used beforehand. Convulsive therapy was introduced in 1934 by Hungarian neuropsychiatrist Ladislas J. Meduna who, believing mistakenly that schizophrenia and epilepsy were antagonistic disorders, induced seizures first with camphor and then metrazol (cardiazol). The first patient was treated by Lucio Bini and Ugo Cerlettiin. ECT is generally administered three times a week for about 8-12 treatments.
- As a surgical tool for cutting or coagulation. An "Electrosurgical Unit" (or ESU) uses high currents (e.g. 10 amperes) at high frequency (e.g. 500 kHz) with various schemes of amplitude modulation to achieve the desired result - cut or coagulate - or both. These devices are safe when used correctly.
- As a treatment for fibrillation or irregular heart rhythms: see defibrillator and cardioversion.
- As a method of pain relief: see Transcutaneous Electrical Nerve Stimulator (more commonly referred to as a TENS unit).
- As an aversive punishment for conditioning of developmentally delayed individuals with severe behavioral problems. This controversial skin-shock method is employed only at the Judge Rotenberg Educational Center, a special needs school in Massachusetts.
- As a treatment for Hyperhidrosis with the device called iontophoresis
- As part of electrodiagnosis diagnostic tests including nerve conduction studies and electromyography.
- For genetic engineering and gene delivery using a non-viral vector system electroporation
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.
With proper treatment, people usually recover in two to three weeks. The condition can, however, be fatal within hours.
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.
The second stage features the reabsorption of the initially extravasated fluid and albumin from the tissues, and it usually lasts 1 to 2 days. Intravascular fluid overload leads to polyuria and can cause flash pulmonary edema and cardiac arrest, with possibly fatal consequences. Death from SCLS typically occurs during this recruitment phase because of pulmonary edema arising from excessive intravenous fluid administration during the earlier leak phase. The severity of the problem depends on to the quantity of fluid supplied in the initial phase, the damage that may have been sustained by the kidneys, and the promptness with which diuretics are administered to help the patient discharge the accumulated fluids quickly. A recent study of 59 acute episodes occurring in 37 hospitalized SCLS patients concluded that high-volume fluid therapy was independently associated with poorer clinical outcomes, and that the main complications of SCLS episodes were recovery-phase pulmonary edema (24%), cardiac arrhythmia (24%), compartment syndrome (20%), and acquired infections (19%).
The prevention of episodes of SCLS has involved two approaches. The first has long been identified with the Mayo Clinic, and it recommended treatment with beta agonists such as terbutaline, phosphodiesterase-inhibitor theophylline, and leukotriene-receptor antagonists montelukast sodium.
The rationale for use of these drugs was their ability to increase intracellular cyclic AMP (adenosine monophosphate) levels, which might counteract inflammatory signaling pathways that induce endothelial permeability. It was the standard of care until the early 2000s, but was sidelined afterwards because patients frequently experienced renewed episodes of SCLS, and because these drugs were poorly tolerated due to their unpleasant side effects.
The second, more recent approach pioneered in France during the last decade (early 2000s) involves monthly intravenous infusions of immunoglobulins (IVIG), with an initial dose of 2 gr/kg/month of body weight, which has proven very successful as per abundant case-report evidence from around the world.
IVIG has long been used for the treatment of autoimmune and MGUS-associated syndromes, because of its potential immunomodulatory and anticytokine properties. The precise mechanism of action of IVIG in patients with SCLS is unknown, but it is likely that it neutralizes their proinflammatory cytokines that provoke endothelial dysfunction. A recent review of clinical experience with 69 mostly European SCLS patients found that preventive treatment with IVIG was the strongest factor associated with their survival, such that an IVIG therapy should be the first-line preventive agent for SCLS patients. According to a recent NIH survey of patient experience, IVIG prophylaxis is associated with a dramatic reduction in the occurrence of SCLS episodes in most patients, with minimal side effects, such that it may be considered as frontline therapy for those with a clear-cut diagnosis of SCLS and a history of recurrent episodes.
If the person has been sufficiently fluid resuscitated but the mean arterial pressure is not greater than 65 mmHg, vasopressors are recommended. Norepinephrine (noradrenaline) is recommended as the initial choice. If a single vasopressor is not enough to raise the blood pressure, epinephrine (adrenaline) or vasopressin may be added. Dopamine is typically not recommended. Dobutamine may be used if heart function is poor or blood flow is insufficient despite sufficient fluid volumes and blood pressure.
General anaesthesia is recommended for people with sepsis who require surgical procedures to remove the infective source. Inhalational and intravenous anaesthetics are used. Requirements for anaesthetics may be reduced. Inhalational anaesthetics can reduce the level of proinflammatory cytokines, altering leukocyte adhesion and proliferation, inducing apoptosis (cell death) of the lymphocytes, possibly with a toxic effect on mitochondrial function. Although etomidate has a minimal effect on the cardiovascular system, it is often not recommended as a medication to help with intubation in this situation due to concerns it may lead to poor adrenal function and an increased risk of death. The small amount of evidence there is, however, has not found a change in the risk of death with etomidate.
It is recommended that the head of the bed be raised if possible to improve ventilation. Paralytic agents should be avoided unless ARDS is suspected.
Generally, the treatment for SIRS is directed towards the underlying problem or inciting cause (i.e. adequate fluid replacement for hypovolemia, IVF/NPO for pancreatitis, epinephrine/steroids/diphenhydramine for anaphylaxis).
Selenium, glutamine, and eicosapentaenoic acid have shown effectiveness in improving symptoms in clinical trials. Other antioxidants such as vitamin E may be helpful as well.
Septic treatment protocol and diagnostic tools have been created due to the potentially severe outcome septic shock. For example, the SIRS criteria were created as mentioned above to be extremely sensitive in suggesting which patients may have sepsis. However, these rules lack specificity, i.e. not a true diagnosis of the condition, but rather a suggestion to take necessary precautions. The SIRS criteria are guidelines set in place to ensure septic patients receive care as early as possible.
In cases caused by an implanted mesh, removal (explantation) of the polypropylene surgical mesh implant may be indicated.
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 treatment of mesenteric ischemia depends on the cause, and can be medical or surgical. However, if bowel has become necrotic, the only treatment is surgical removal of the dead segments of bowel.
In non-occlusive mesenteric ischemia, where there is no blockage of the arteries supplying the bowel, the treatment is medical rather than surgical. People are admitted to the hospital for resuscitation with intravenous fluids, careful monitoring of laboratory tests, and optimization of their cardiovascular function. NG tube decompression and heparin anticoagulation may also be used to limit stress on the bowel and optimize perfusion, respectively.
Surgical revascularisation remains the treatment of choice for mesenteric ischaemia related to an occlusion of the vessels supplying the bowel, but thrombolytic medical treatment and vascular interventional radiological techniques have a growing role.
If the ischemia has progressed to the point that the affected intestinal segments are gangrenous, a bowel resection of those segments is called for. Often, obviously dead segments are removed at the first operation, and a second-look operation is planned to assess segments that are borderline that may be savable after revascularization.
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.
The initial stage is the capillary leak phase, lasting from 1 to 3 days, during which up to 70% of total plasma volume may invade cavities especially in the extremities. The most common clinical features are flu-like symptoms such as fatigue; runny nose; lightheadedness up to and including syncope (fainting); limb, abdominal or generalized pain; facial or other edema; dyspnea; and hypotension that results in circulatory shock and potentially in cardiopulmonary collapse and other organ distress or damage. Acute renal dysfunction or failure is a common risk due to acute tubular necrosis consequent to hypovolemia and rhabdomyolysis.
The loss of fluid out of the capillaries has similar effects on the circulation as dehydration, slowing both the flow of oxygen delivered to tissues and organs as well as the output of urine. Urgent medical attention in this phase consists of fluid resuscitation efforts, mainly the intravenous administration of saline solution plus hetastarch or albumin and colloids (to increase the remaining blood flow to vital organs like the kidneys), as well as glucocorticoids (steroids like methylprednisolone, to reduce or stop the capillary leak). However effective on blood pressure, the impact of fluid therapy is always transient and leads to increased extravascular fluid accumulation, engendering multiple complications especially compartment syndrome and thus limb-destructive rhabdomyolysis. Consequently, patients experiencing episodes of SCLS should be closely monitored in a hospital intensive-care setting, including for orthopedic complications requiring surgical decompression, and their fluid therapy should be minimized as much as possible.
Fulminant infection from meningococci bacteria in the bloodstream is a medical emergency and requires emergent treatment with adequate antibiotics. Benzylpenicillin was once the drug of choice with chloramphenicol as a good alternative in allergic patients. Ceftriaxone is an antibiotic commonly employed today. Hydrocortisone can sometimes reverse the adrenal insufficiency. Plastic surgery and tissue grafting are sometimes needed to treat tissue necrosis resulting from the infection.
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.
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.