We investigated the hemostatic efficacy of Cutanplast Standard and Fast gelatin sponge products and Emosist ORC gauze in a range of porcine models of mild-to-moderate surgical bleeding that are expected to be predictive of clinical efficacy. These were porcine liver abrasion, incision, and puncture, and spleen incision and puncture models. Cutanplast gelatin powder products were only evaluated in porcine liver abrasion and incision models. We do not consider our liver puncture or spleen puncture and incision models relevant to the clinical conditions for which powdered topical hemostats are indicated (mild bleeding or oozing from a relatively diffuse bleeding surface).
In our liver abrasion and incision models, rapid hemostasis (generally ≤ 2–5 min) was achieved with all Cutanplast gelatin sponge and powder products, which were at least as effective as Emosist ORC gauze. Cutanplast Standard gelatin powder was particularly effective in the liver abrasion model, with no observed bleeding and time to hemostasis ≤ 2 min. Hemorrhage was also well controlled with Cutanplast Standard and Fast gelatin sponge products and Cutanplast Fast gelatin powder in the liver incision model, with mild-to-no capillary-like bleeding with ooze or intermittent flow, and time to hemostasis of ≤ 2–5 min, whereas time to hemostasis tended to be > 5 min with Cutanplast Standard gelatin powder and Emosist ORC gauze in this model. Inferior hemostasis occurred with Cutanplast Standard gelatin sponge versus Cutanplast Fast gelatin sponge and Emosist ORC gauze in the liver puncture and spleen puncture and incision models. This was most evident for the spleen incision model, in which a continuous flow of blood was observed and time to hemostasis approached 10 min with Cutanplast Standard gelatin sponge, whereas ooze or intermittent flow was observed with Cutanplast Fast gelatin sponge and Emosist ORC gauze products, with hemostasis taking place in 2–5 min.
Surgical bleeding can range from mild or moderate in intensity to severe or traumatic [1]. In general, topical hemostats can be used to achieve hemostasis on the surface of parenchymal organs, but other methods of hemostasis are recommended when there is a relatively large amount of bleeding (i.e., pulsatile/spurting arterial or high volume venous bleeding rather than mild-to-moderate hemorrhage or diffuse oozing) [9, 20]. Porcine liver abrasion, incision, and punch biopsy models have previously been used to assess the efficacy of gelatin and ORC hemostat products on diffuse and focused mild-to-moderate surgical bleeding [19–21, 26, 27]. The effectiveness of gelatin and ORC hemostatic products has also previously been demonstrated in relation to injuries to the spleen, which is an organ where hemostasis is relatively difficult to achieve [28–30]. As opposed to abrasions and shallow incisions (2–3 mm), which generally result in a mixture of venous-, venule-, and arteriolar-like bleeding [19], our 6–7-mm deep liver and spleen incision models mimicked a relatively severe surgical injury, with more potential for flowing venous and/or arterial bleeding.
During surgery, effective hemostasis through the adjunctive use of hemostatic agents can reduce operating times, blood loss, and the need for transfusions [31, 32]. However, the comparative effectiveness of topical hemostatic agents is highly procedure specific [6], and the most appropriate product needs to be selected, taking into consideration factors such as the intensity of bleeding, surgical site, and type of surgical procedure [2, 5, 10, 13, 31, 33]. To maximize effectiveness and reduce the risk of hemostatic agent failure, comparison of efficacy of hemostatic agents used in routine surgery is important in order to guide selection of the appropriate hemostatic agent [21, 25]. To date, Cutanplast gelatin sponge has been shown to be a clinically effective hemostat in endoscopic sinus surgery and thyroid surgery [16–18], and Emosist ORC gauze ensured adequate hemostasis in patients undergoing laparoscopic cholecystectomy with bleeding not adequately controlled by conventional techniques [9]. Our in vivo observations suggest that these products could also be used successfully in other surgical applications.
The current study was purely observational with a small sample size (five pigs). It was designed to support in vitro studies on the efficacy of our hemostatic products using in vivo models that are relevant to clinical practice. There were therefore no formal statistical comparisons of the hemostatic effectiveness of the different hemostatic products. In addition to the qualitative parameters of blood loss, time to hemostasis was assessed (an important factor to consider when choosing a topical hemostat [29]), and the rate of blood loss was quantified if time to hemostasis was not achieved within 2 min of application of the hemostatic device. These two latter quantitative parameters were designed to support subjective and potentially inaccurate visual estimation of blood loss.