Septic shock: diagnosis and treatment of intensive care

2021-08-01 11:28 PM

Septic shock, which is a phase of a continuum, starting with a systemic inflammatory response to infection, severe sepsis, septic shock, and multiple organ failure

Sepsis was defined as life-threatening organ dysfunction due to a host regulatory response to infection, and organ dysfunction was defined as an acute change.

The septic shock occurred in a subgroup of patients with sepsis and consisted of underlying circulatory and cellular/metabolic abnormalities that were associated with increased mortality.

Septic shock is defined by persistent hypotension requiring vasopressors to maintain mean arterial pressure of 65 mm Hg or higher and serum lactate level greater than 2 mmol/L (18 mg/dL). despite adequate volume resuscitation.

Septic shock is a severe form of infection that causes 40-60% mortality.

Following the international recommendations for infection control and treatment (Surviving Sepsis Campaign) has been shown to reduce mortality from septic shock and is being applied widely.

Septic shock is a phase of a continuum that begins with a systemic inflammatory response to infection, severe sepsis, septic shock, and multiple organ failure.

Definitive diagnosis: meeting all 3 of the following criteria:

Severe infections have a source of infection.

Dysfunction of at least one organ.

Hypotension is unresponsive to fluid replacement.

Test:

+ Confirm infection such as complete blood count, neutrophil count, erythrocyte sedimentation rate, CRP, procalcitonin.

Blood lactate.

Differential diagnosis

Hypovolemic shock: dehydration or blood loss, low central venous pressure, shock that responds well to fluid or blood replacement.

Cardiogenic shock: occurs after acute myocardial infarction with low EF.

Anaphylaxis: often associated with allergens with manifestations of hypersensitivity.

Diagnose the cause

Ask the patient and examine the patient for the entry of the infection.

Diagnostic imaging: echocardiography, chest X-ray, CT scan, etc. to help diagnose the path to infection.

Blood culture: take 2 samples, one intravenously that has been stored for more than 48 hours and one through the peripheral route, note-taking blood before taking antibiotics.

Screening, the culture of body fluids if suspected to be the entrance or foci of disease such as sputum, urine, pleural blindness...

Diagnosis of severity

The progression of multiple organ failure is a major prognostic factor.

Gradual elevation of lactate and hypotension unresponsive to vasopressors are severe manifestations of shock.

Treatment

Fluid volume compensation

Initial infusion in the presence of hypotension with goals to be achieved within the first 6 hours.

Maintain central venous pressure 11-16cm of water.

Maintain mean blood pressure > 65 mmHg.

+ Maintain ScvO 2 ≥ 70% or SvO 2 ≥ 65%.

+ Urine volume ≥ 0.5ml/kg/hour.

Measures to be taken (see volume therapy for the first 6 hours for patients with septic shock).

Use vasomotor

Use vasopressors only when adequate fluid resuscitation is available.

Dopamine or Noradrenaline is the first choice. Dopamine starting dose 5μg/kg/min, gradually increase dose 3-5μg after 5-10 minutes if no response, maximum dose 20μg/kg/min. Noradrenaline starting dose 0.05μg/kg/min and gradually increasing dose 0.05μg after 5-10 minutes if no response, maximum dose 5μg/kg/min.

Add Dobutamine if unable to maintain Scv02 > 70% or Sv02 > 65%. Initial dose 3 μg/kg/min, gradually increased dose 3-5 μl every 5-10 minutes if no response, maximum 20 μg/kg/min.

Use antibiotics

Administer intravenously as soon as possible, preferably within the first hour after diagnosis of infection. Note the use of antibiotics after blood culture.

Use broad-spectrum antibiotics according to empiric antibiotic therapy and de-escalate.

Combination of antibiotics in the following cases:

+ If the patient has leukopenia, it is necessary to combine antibiotics with maximum coverage of the infection spectrum (Gram-negative, Gram-positive, or intracellular bacteria...).

+ If blue pus bacillus infection is suspected, Acinetobacter baumanni should be combined with antibiotics sensitive to blue pus bacilli.

+ If intestinal coccidiosis is suspected, add antibiotics sensitive to enteric cocci such as vancomycin, cubicin...

Note in patients with renal impairment, antibiotic dose must be based on creatinine clearance, the first dose is used as usual without dose adjustment, only dose adjustment from the following doses.

Use hydrocortisone

Use only when the shock is poorly responsive to vasopressors or vasopressors have not been terminated after 48 hours, caution is not used systematically.

Dosage: 50mg every 6 hours.

Reduce dose and stop when patient is out of shock and vasopressor is removed.

Note that it can make the infection worse and cause hyperglycemia.

Blood sugar control

Control capillary blood sugar with insulin.

Capillary blood sugar >11 mmol/l, intermittent rapid insulin therapy, or continuous intravenous infusion depending on the patient's hyperglycemia.

Maintain blood sugar between 7 - 9mmol/l.

Preventive treatment of complications

Venous thrombosis.

+ Low molecular weight heparin such as Enoxaparin 1mg/kg subcutaneously. Reduce dose in patients with renal impairment.

Use condoms to periodically change the pressure on both arms and legs.

Gastrointestinal bleeding: use gastric mucosal drugs or proton pump inhibitors, note the route of administration and drug interactions.

Artificial ventilation

Objective: SpO 2 > 92% or PaO 2 > 60mmHg and pH > 7.15 by the following measures:

Non-invasive artificial ventilation with CPAP or BiPAP if the patient is awake and cooperative.

Invasive ventilation using PEEP if there is no contraindication to PEEP when non-invasive ventilation fails or the patient is uncooperative (see the article on artificial ventilation for patients with severe lung injury and ARDS). ).

If ARDS is present, artificially ventilate according to the lung-protective ventilation strategy.

Solve the source of infection

The source of infection must be addressed by puncture, aspiration, drainage or surgery if indicated (must be done before continuous dialysis).

Continuous dialysis

Continuous hemodialysis as soon as possible after a diagnosis of septic shock, taking care only when the infection has been resolved by aspiration, drainage, or surgical surgery if indicated.

Dialysis should be performed only when systolic blood pressure > 90 mmHg has been raised by intravenous fluids and vasopressors.

Large volume of fluid replacement: > 45ml/kg/hour.

The maintenance time for 1 filter is 18-22 hours.

Bicarbonate or citrate filtrate.

Use heparin or citrate anticoagulation if there are no contraindications.

Extensive pre-membrane dilution if the patient has severe coagulopathy.

Strictly follow operating procedures for dialysis machine pumps for hemodynamically unstable patients.

Complications during dialysis must be closely monitored: hypotension, bleeding, hemolysis...

Discontinue continuous dialysis when vasopressors are removed and switch to intermittent dialysis if indicated.

Artificial heart and lungs

If continuous dialysis is unsuccessful, cardiopulmonary bypass (ECMO) should be considered.

Preventive

Early detection and treatment of infections.