-
Current Opinion in Critical Care Dec 2020This review discusses the macrocirculatory and microcirculatory aspects of renal perfusion, as well as novel methods by which to measure renal blood flow. Finally,... (Review)
Review
PURPOSE OF REVIEW
This review discusses the macrocirculatory and microcirculatory aspects of renal perfusion, as well as novel methods by which to measure renal blood flow. Finally, therapeutic options are briefly discussed, including renal-specific microcirculatory effects.
RECENT FINDINGS
The optimal mean arterial pressure (MAP) needed for preservation of renal function has been debated but is most likely a MAP of 60-80 mmHg. In addition, attention should be paid to renal outflow pressure, typically central venous pressure. Heterogeneity in microcirculation can exist and may be mitigated through appropriate use of vasopressors with unique microcirculatory effects. Excessive catecholamines have been shown to be harmful and should be avoided. Both angiotensin II and vasopressin may improve glomerular flow through a number of mechanisms. Macrocirculatory and microcirculatory blood flow can be measured through a number of bedside ultrasound modalities, sublingual microscopy and urinary oxygen measurement, SUMMARY: Acute kidney injury (AKI) is a common manifestation of organ failure in shock, and avoidance of hemodynamic instability can mitigate this risk. Measurement of renal haemodynamics is not routinely performed but may help to guide therapeutic goals. A thorough understanding of pathophysiology, measurement techniques and therapeutic options may allow for a personalized approach to blood pressure management in patients with septic shock and may ultimately mitigate AKI.
Topics: Hemodynamics; Humans; Microcirculation; Renal Circulation; Shock, Septic; Vasoconstrictor Agents
PubMed: 33044238
DOI: 10.1097/MCC.0000000000000774 -
The Laryngoscope Aug 2016
Review
Topics: Administration, Topical; Cocaine; Endoscopy; Hemostasis, Surgical; Humans; Paranasal Sinuses; Vasoconstrictor Agents
PubMed: 27075241
DOI: 10.1002/lary.25836 -
Expert Review of Anti-infective Therapy Jan 2017Distributive shock is associated with decreased systemic vascular resistance and altered oxygen extraction. Septic shock is the most frequent form of distributive shock.... (Review)
Review
Distributive shock is associated with decreased systemic vascular resistance and altered oxygen extraction. Septic shock is the most frequent form of distributive shock. In shock states, duration of hypotension is associated with poor outcomes. The speed at which treatment to restore adequate perfusion pressure is initiated is, therefore, important to improve survival. Areas covered: This review presents an overview of the literature related to the management of vasopressor-dependent distributive shock, and in particular the relationship between arterial pressure and organ perfusion and function. Studies that have tried to determine an optimal blood pressure level are discussed demonstrating that it is difficult to define and will vary according to individual patient factors, including age and a history of chronic hypertension. An initial target mean arterial pressure (MAP) of 65-70 mmHg is probably sufficient in most patients. The influence of increasing MAP on the microcirculation is also covered. Expert commentary: Microcirculatory monitoring may be the best way to individualize management of these patients, but remains experimental at present. In the meantime, repeated blood lactate levels and venous oxygen saturations, combined with hemodynamic variables and the clinical picture, can provide an indication of the response to treatment and adequacy of tissue perfusion.
Topics: Blood Flow Velocity; Blood Pressure; Humans; Microcirculation; Practice Guidelines as Topic; Shock, Septic; Vascular Resistance; Vasoconstrictor Agents
PubMed: 27774825
DOI: 10.1080/14787210.2017.1252673 -
Shock (Augusta, Ga.) May 2017Refractory septic shock is defined as persistently low mean arterial blood pressure despite volume resuscitation and titrated vasopressors/inotropes in patients with a... (Review)
Review
Refractory septic shock is defined as persistently low mean arterial blood pressure despite volume resuscitation and titrated vasopressors/inotropes in patients with a proven or suspected infection and concomitant organ dysfunction. Its management typically requires high doses of catecholamines, which can induce significant adverse effects such as ischemia and arrhythmias. Angiotensin II (Ang II), a key product of the renin-angiotensin-aldosterone system, is a vasopressor agent that could be used in conjunction with other vasopressors to stabilize critically ill patients during refractory septic shock, and reduce catecholamine requirements. However, very few clinical data are available to support Ang II administration in this setting. Here, we review the current literature on this topic to better understand the role of Ang II administration during refractory septic shock, differentiating experimental from clinical studies. We also consider the potential role of exogenous Ang II administration in specific organ dysfunction and possible pitfalls with Ang II in sepsis. Various issues remain unresolved and future studies should investigate important topics such as: the optimal dose and timing of Ang II administration, a comparison between Ang II and the other vasopressors (epinephrine; vasopressin), and Ang II effects on microcirculation.
Topics: Angiotensin II; Hemodynamics; Humans; Shock, Septic; Vasoconstrictor Agents
PubMed: 27879559
DOI: 10.1097/SHK.0000000000000807 -
Neonatology 2024Epinephrine (adrenaline) is currently the only cardiac agent recommended during neonatal resuscitation. The inability to predict which newborns are at risk of requiring... (Review)
Review
BACKGROUND
Epinephrine (adrenaline) is currently the only cardiac agent recommended during neonatal resuscitation. The inability to predict which newborns are at risk of requiring resuscitative efforts at birth has prevented the collection of large, high-quality human data.
SUMMARY
Information on the optimal dosage and route of epinephrine administration is extrapolated from neonatal animal studies and human adult and pediatric studies. Adult resuscitation guidelines have previously recommended vasopressin use; however, neonatal studies needed to create guidelines are lacking. A review of the literature demonstrates conflicting results regarding epinephrine efficacy through various routes of access as well as vasopressin during asystolic cardiac arrest in animal models. Vasopressin appears to improve hemodynamic and post-resuscitation outcomes compared to epinephrine in asystolic cardiac arrest animal models.
KEY MESSAGES
The current neonatal resuscitation guidelines recommend epinephrine be primarily given via the intravenous or intraosseous route, with the endotracheal route as an alternative if these routes are not feasible or unsuccessful. The intravenous or intraosseous dose ranges between 0.01 and 0.03 mg/kg, which should be repeated every 3-5 min during chest compressions. However, the optimal dosing and route of administration of epinephrine remain unknown. There is evidence from adult and pediatric studies that vasopressin might be an alternative to epinephrine; however, the neonatal data are scarce.
Topics: Animals; Infant, Newborn; Child; Humans; Resuscitation; Cardiopulmonary Resuscitation; Epinephrine; Heart Arrest; Vasopressins; Animals, Newborn; Vasoconstrictor Agents
PubMed: 38228124
DOI: 10.1159/000535502 -
International Journal of Dermatology Oct 1992The vasoconstrictor assay, when properly performed, is a highly reliable method to determine bioequivalence of generic formulations. Recent research has resolved some of... (Review)
Review
The vasoconstrictor assay, when properly performed, is a highly reliable method to determine bioequivalence of generic formulations. Recent research has resolved some of the remaining questions concerning the practical application of the assay. Significant vehicle-related differences have been observed between the potency of different, supposedly equivalent formulations now on the market. Large differences in concentrations of the active agent in similar vehicles usually have not resulted in corresponding differences in vasoconstrictor assay results. Finally, the time course of drug effects may differ among highly potent and less potent corticosteroids. In general, the higher the potency of the topical corticosteroid, the earlier the maximal effect is observed. This finding suggests that short application of highly potent agents might minimize systemic absorption without sacrificing efficacy.
Topics: Administration, Topical; Anti-Inflammatory Agents; Glucocorticoids; Humans; Pharmaceutical Vehicles; Skin; Therapeutic Equivalency; Time Factors; Vasoconstrictor Agents
PubMed: 1428464
DOI: 10.1111/j.1365-4362.1992.tb04009.x -
Gastrointestinal Endoscopy Aug 2015
Topics: Epinephrine; Female; Gastrointestinal Hemorrhage; Humans; Intestinal Perforation; Male; Polyethylene Glycols; Postoperative Hemorrhage; Sclerosing Solutions; Vasoconstrictor Agents
PubMed: 26183495
DOI: 10.1016/j.gie.2015.05.010 -
Current Opinion in Critical Care Aug 2017Norepinephrine is the first-line agent recommended during resuscitation of septic shock to correct hypotension due to depressed vascular tone. Important clinical issues... (Review)
Review
PURPOSE OF REVIEW
Norepinephrine is the first-line agent recommended during resuscitation of septic shock to correct hypotension due to depressed vascular tone. Important clinical issues are the best timing to start norepinephrine, the optimal blood pressure target, and the best therapeutic options to face refractory hypotension when high doses of norepinephrine are required to reach the target.
RECENT FINDINGS
Recent literature has reported benefits of early administration of norepinephrine because of the following reasons: profound and durable hypotension is an independent factor of increased mortality, early administration of norepinephrine increases cardiac output, improves microcirculation and avoids fluid overload. Recent data are in favor of targeting a mean arterial pressure of at least 65 mmHg and higher values in case of chronic hypertension. When hypotension is refractory to norepinephrine, it is recommended adding vasopressin, which is relatively deficient during sepsis and acts on other vascular receptors than α1-adernergic receptors. However, increasing the dose of norepinephrine further cannot be discouraged.
SUMMARY
Early administration of norepinephrine is beneficial for septic shock patients to restore organ perfusion. The mean arterial pressure target should be individualized. Adding vasopressin is recommended in case of shock refractory to norepinephrine.
Topics: Blood Pressure; Humans; Norepinephrine; Shock, Septic; Vasoconstrictor Agents
PubMed: 28509668
DOI: 10.1097/MCC.0000000000000418 -
Carbohydrate Polymers Apr 2021Chitosan (Cs) as a hemostatic agent has been in use to control hemorrage. Composite hydrogel formed by entrapment of vasoconstrictor-potassium aluminium sulfate (0.25...
Chitosan (Cs) as a hemostatic agent has been in use to control hemorrage. Composite hydrogel formed by entrapment of vasoconstrictor-potassium aluminium sulfate (0.25 %PA) and coagulation activator-calcium chloride (0.25 %Ca) into Cs (2 %) hydrogel would enhance the hemostatic property of Cs. In this work, the prepared composite hydrogel was injectable, shear thinning, cyto and hemocompatible. The 2 %Cs-0.25 %PA-0.25 %Ca composite hydrogel caused rapid blood clotting by accelerating RBC/platelet aggregation and activation of the coagulation cascade. Further, in vivo studies on rat liver and femoral artery hemorrage model showed the efficiency of 2 %Cs-0.25 %PA-0.25 %Ca composite hydrogel to achieve hemostasis in a shorter time (20 ± 10 s, 105 ± 31 s) than commercial hemostatic agents-Fibrin sealant (77 ± 26 s, 204 ± 58 s) and Floseal (76 ± 15 s, 218 ± 46 s). In in vivo toxicological study, composite hydrogel showed material retention even after 8 weeks post-surgery, therefore excess hydrogel should be irrigated from site of application. This prepared composite hydrogel based hemostatic agent has potential application in low pressure bleeding sites.
Topics: Animals; Blood Coagulation; Blood Platelets; Calcium; Chitosan; Erythrocytes; Femoral Artery; Hemorrhage; Hemostasis; Hemostatics; Human Umbilical Vein Endothelial Cells; Humans; Hydrogels; Liver; Male; Platelet Aggregation; Rats; Rats, Sprague-Dawley; Swine; Vasoconstriction; Vasoconstrictor Agents
PubMed: 33593536
DOI: 10.1016/j.carbpol.2021.117634 -
Anesthesiology May 2022
Topics: Cerebrovascular Circulation; Microcirculation; Norepinephrine; Vasoconstrictor Agents
PubMed: 35157755
DOI: 10.1097/ALN.0000000000004150