From the Guidelines
The correct answer is (d) microfibrillar collagen (Avitene). Microfibrillar collagen directly induces coagulation by providing a physical matrix that attracts and activates platelets, triggering the intrinsic coagulation pathway, as supported by studies such as 1. When applied to bleeding surfaces, the collagen fibrils interact with platelets, causing them to adhere, aggregate, and release factors that promote clot formation. Unlike the other options, microfibrillar collagen actively participates in the coagulation cascade rather than just providing a passive barrier.
Some key points to consider when evaluating these options include:
- Superglue (cyanoacrylate) works by forming a mechanical seal, which does not directly induce coagulation.
- Oxidized cellulose provides a physical matrix and generates an acidic environment that denatures blood proteins, but its effect on coagulation is less direct compared to microfibrillar collagen.
- Absorbable gelatin sponge works primarily as a physical scaffold that supports clot formation but doesn't directly activate the coagulation cascade like microfibrillar collagen does, as noted in studies like 1 and 1.
The most recent and highest quality study, 1, highlights the effectiveness of microfibrillar collagen in inducing coagulation, making it the preferred choice. It's essential to prioritize the most recent evidence when making clinical decisions, especially in the context of managing bleeding and coagulopathy, as seen in 1.
From the Research
Coagulation Inducers
The following options directly induce coagulation:
- (b) oxidized cellulose: According to the study 2, oxidized cellulose is an effective hemostat that works naturally to aid in blood coagulation. The mechanism of its action is not very well understood, but it has been found to activate blood platelets, which is a crucial step in the coagulation process.
- (c) absorbable gelatin sponge: Although there is no direct evidence provided in the given studies, absorbable gelatin sponges are known to promote hemostasis by providing a scaffold for clot formation.
- (d) microfibrillar collagen (Avitene): The study 3 states that microfibrillar collagen hemostat (Avitene) is a new absorbable hemostatic agent, of which mechanisms are adhesion to the bleeding site and platelet aggregation, directly inducing coagulation.
Non-Coagulation Inducers
The following option does not directly induce coagulation:
- (a) superglue: There is no evidence provided in the given studies to suggest that superglue directly induces coagulation.