This study aims to investigate the effect of angiotensin II on microcirculation and peripheral perfusion in patients with septic shock.
Shock is a syndrome characterized by acute circulatory failure resulting in impaired peripheral tissue perfusion. Distributive shock is the most common type of shock and is usually caused by severe sepsis. Distributive shock is characterized by profound vasodilatation leading to decreased arterial blood pressure and impaired organ perfusion despite high cardiac output. The use of vasopressors is an essential management line for distributive sock. Two groups of vasopressors are usually used for management of shock: catecholamines and vasopressin-like peptides. There is a continuous need for other vasopressors because: 1- Available vasopressors have narrow therapeutic window. 2- Patients with severe hypotension refractory to the currently available classes usually die. A third system is usually engaged in the physiology of shock which is Renin-Angiotensin-aldosterone system. Angiotensin II is a natural hormone which is a potent vasopressor; moreover, angiotensin II stimulates the production of both antidiuretic hormone and adrenocorticotropin hormone. In a pilot study, angiotensin II was reported as an effective rescue vasopressor in septic shock patients on multiple vasopressors. Angiotensin II improved mean arterial pressure and helped in reduction of the doses of catecholamines. In a recent large randomized controlled trial, angiotensin II improved blood pressure in catecholamine-resistant distributive shock patients. Microcirculation is the primary site of oxygen and nutrient exchange. Maintenance of microcirculatory perfusion is a prerequisite for preservation of organ function. Multiple organ failure is common in patients with distributive shock despite maintenance of parameters of global perfusion due to disrupted microcirculatory perfusion. Furthermore, restoration of microcirculatory perfusion was correlated with improvement in survival. This study aims to investigate the effect of angiotensin II on peripheral microcirculation in patients with septic shock.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
QUADRUPLE
Enrollment
20
Patients will receive angiotensin-II at a starting dose of 20 ng/Kg/min.
Patients will receive normal saline.
patients will receive norepinephrine infusion adjusted according to blood pressure
Cairo University
Cairo, Egypt
Mean flow index
Mean flow index measured by Side stream dark field imaging optical probe (Microscan; MicroVision Medical, Amsterdam, Netherlands). Briefly, after gentle cleansing of the tongue by isotonic-saline-drenched gauze, avoiding pressure artifacts, 5 steady images of at least 20 seconds each will be obtained and stored under a random number. Offline blind analysis of each video will be done using a dedicated software (Automated Vascular Analysis 3.0; Academic Medical Center, University of Amsterdam, The Netherlands). The microvascular flow index (MFI) will be used to quantify microvascular blood flow. In this score, flow is characterized as absent (0), intermittent (1), sluggish (2), or normal (3), for each patient the values from 5 videos will be averaged. Since our investigation will be focused on small vessels, calculations will be separately performed for vessels with a diameter less than 20 ųm.
Time frame: 6 Hours
Proportion of perfused vessels
Proportion of perfused vessels measured by Side stream dark field imaging optical probe (Microscan; MicroVision Medical, Amsterdam, Netherlands). Briefly, after gentle cleansing of the tongue by isotonic-saline-drenched gauze, avoiding pressure artifacts, 5 steady images of at least 20 seconds each will be obtained and stored under a random number. Offline blind analysis of each video will be done using a dedicated software (Automated Vascular Analysis 3.0; Academic Medical Center, University of Amsterdam, The Netherlands)
Time frame: 6 Hours
Perfused vessel density
Perfused vessel density measured by Side stream dark field imaging optical probe (Microscan; MicroVision Medical, Amsterdam, Netherlands). Briefly, after gentle cleansing of the tongue by isotonic-saline-drenched gauze, avoiding pressure artifacts, 5 steady images of at least 20 seconds each will be obtained and stored under a random number. Offline blind analysis of each video will be done using a dedicated software (Automated Vascular Analysis 3.0; Academic Medical Center, University of Amsterdam, The Netherlands)
Time frame: 6 Hours
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
systolic blood pressure
systolic blood pressure measured in mmHg
Time frame: 6 hours
Diastolic blood pressure
diastolic blood pressure measured in mmHg
Time frame: 6 hours
Heart rate
heart rate in beats per minute
Time frame: 6 hours
Serum lactate
Serum lactate measured in milligrams per deciliter
Time frame: 6 hours
Urine output
quantity of urine in milliliters
Time frame: 6 hours
Serum Creatinine
serum creatinine measured in milligrams per deciliter
Time frame: 24 hours
Serum Sodium
Serum sodium measured in milligrams per deciliter
Time frame: 24 hours
Serum potassium
Serum potassium measured in milligrams per deciliter
Time frame: 24 hours
Cardiac output
quantity of blood pumper by the heart measured by electrical cardiometry in liters per minute
Time frame: 6 hours
systemic vascular resistance
systemic vascular resistance measured by electrical cardiometry
Time frame: 6 hours
Norepinephrine requirements
total requirement of norepinephrine needed to maintain mean arterial blood pressure above 65 mmHg
Time frame: 6 hours
perfusion index
proportion of pulsatile to non-pulsatile portions in peripheral circulation
Time frame: 6 hours
total fluid intake
amount of fluids received by the patient in milliliters
Time frame: 24 hours