From the Guidelines
Management of persistently low pressure despite fluid resuscitation requires the initiation of norepinephrine as the first-line vasopressor, as it is the most effective agent for maintaining a mean arterial pressure (MAP) of at least 65 mmHg, according to the most recent guidelines 1. The use of norepinephrine is supported by the latest evidence, which suggests that it should be the first-line choice for hypotension that persists after fluid resuscitation 1.
- Key considerations in the management of persistently low blood pressure include:
- Initial fluid resuscitation with crystalloid as the fluid of choice 1
- Use of norepinephrine as the first-line vasopressor, with a dose titrated to achieve a MAP of at least 65 mmHg 1
- Addition of vasopressin if hypotension persists despite norepinephrine use 1
- Ongoing assessment of volume status and identification of the underlying cause of shock, with simultaneous treatment of the underlying condition 1
- The goal of vasopressor therapy is to maintain adequate tissue perfusion by increasing systemic vascular resistance and raising blood pressure, and the choice of vasopressor and dose should be individualized based on the patient's response and underlying condition 1.
- It is essential to note that the optimal MAP should be individualized, as it may be higher in patients with atherosclerosis and/or previous hypertension than in young patients without cardiovascular comorbidity 1.
From the FDA Drug Label
Vasopressin injection is indicated to increase blood pressure in adults with vasodilatory shock who remain hypotensive despite fluids and catecholamines. Vasopressin injection is indicated to increase blood pressure in adults with vasodilatory shock who remain hypotensive despite fluids and catecholamines. (1)
Management of persistently low pressure despite fluid resuscitation may involve the use of vasopressin (IV), as it is indicated for increasing blood pressure in adults with vasodilatory shock who remain hypotensive despite fluids and catecholamines 2 2.
- The dosage of vasopressin injection for post-cardiotomy shock is 0.03 to 0.1 units/minute, and for septic shock is 0.01 to 0.07 units/minute.
- It is essential to dilute the 20 units/mL multiple dose vial contents with normal saline or 5% dextrose in water to either 0.1 units/mL or 1 unit/mL for intravenous administration.
From the Research
Management of Persistently Low Pressure Despite Fluid Resuscitation
- The management of persistently low pressure despite fluid resuscitation is crucial in preventing organ failure, especially acute kidney injury 3, 4, 5, 6, 7.
- According to the study by 3, septic shock is defined as sepsis-induced hypotension persisting despite adequate fluid resuscitation, and the initiation of vasopressor therapy is recommended in patients who remain hypotensive after a crystalloid fluid challenge of 30 mL per kg body weight.
- The use of vasopressors, such as norepinephrine and vasopressin, can help increase mean arterial pressure and prevent organ failure 4, 6, 7.
- However, the choice of vasopressor and the dose used can have different effects on renal hemodynamics, and careful consideration is needed to balance the benefits and risks of vasopressor therapy 4, 7.
- A target systolic arterial pressure of 80-90 mmHg is recommended until the control of hemorrhage in trauma patients without brain injury 6.
- The study by 7 found that restoration of mean arterial pressure from 60 to 75 mmHg improves renal oxygen delivery, glomerular filtration rate, and the renal oxygen supply/demand relationship in post-cardiac surgery patients with vasodilatory shock and acute kidney injury.
- Overall, the management of persistently low pressure despite fluid resuscitation requires a careful and individualized approach, taking into account the underlying cause of shock, the patient's hemodynamic status, and the potential risks and benefits of different therapeutic interventions 3, 4, 5, 6, 7.