Utility of preoperative in vitro platelet function tests for predicting bleeding risk in patients undergoing functional endoscopic sinus surgery

Development and validation of a nomogram for predicting poor operative visibility during FESS in Chinese adult patients with CRS

Objective

The purpose of this study is to develop and evaluate a nomogram that is capable of predicting poor operative visibility during functional endoscopic sinus surgery.

Method

To identify potential risk factors, patients with chronic rhinosinusitis who underwent functional endoscopic sinus surgery (FESS) between January 2019 and December 2022 were selected from our hospital's electronic medical record system. Data on general patient information, clinical manifestations, clotting-related test indices, Lund-Machay score of sinuses CT scanning, Lund-kennedy score of nasal endoscopies, anesthesia methods, intraoperative blood pressure and heart rate, and Boezaart bleeding score were collected. Minimum absolute convergence and selection operator (LASSO) regression, as well as multivariate logistic regression, were used to determine the risk factors. A nomogram was developed in order to predict poor operating visibility during FESS, and its performance was evaluated utilizing both the training and verification datasets via various measures including receiver operating characteristic (ROC) curve analysis, area under the curve (AUC), Hosmer-Lemeshow goodness-of-fit test, calibration curve, and decision curve analysis.

Results

Of the 369 patients who met the inclusion criteria, 88 of them exhibited POV during FESS. By deploying LASSO and multivariate logistic regression analyses, six risk factors were identified and used to construct a nomogram for predicting POV during FESS. These factors include prothrombin time (PT), prothrombin activity (PTA), Lund-Mackay score (LMS), Lund-Kennedy score (LKS), anesthetic method, and intraoperative hypertension. The AUC of the training set was found to be 0.820 while that of the verification set was 0.852. The Hosmer-Lemeshow goodness-of-fit test and calibration curve analysis revealed good consistency between predicted and actual probabilities. Also, the decision curve demonstrated that the nomogram had a high degree of clinical usefulness and net benefit.

Conclusion

The constructed nomogram has a strong ability to predict the poor intraoperative field in patients with chronic rhinosinusitis, which can help preoperative judgment of high-risk patients and provide evidence for perioperative management and preoperative plan formulation.

Is the platelet function test effective in predicting blood loss in patients undergoing hepatic resection?

Purpose

The platelet function analyzer (PFA)-100/200 is widely used to assess platelet function. However, its role in predicting the perioperative risk of bleeding in patients undergoing liver resection remains controversial. Therefore, we aimed to ascertain whether the platelet function test could be useful in predicting bleeding risk in patients undergoing hepatic surgery.

Methods

The study participants were patients who underwent hepatectomy for hepatocellular carcinoma at our hospital over a period of 10 years from January 1, 2010 to May 31, 2020. PFA-200 values of these patients were divided into 2 groups; normal (n = 333) and prolonged (n = 39).

Results

There were no significant differences regarding the volumes of calculated blood loss during surgery between the normal and prolonged PFA groups (879.55 ± 1,046.50 mL vs. 819.74 ± 912.64 mL, respectively; P = 0.733); intraoperative RBC transfusion (0.52 ± 2.02 units vs. 0.26 ± 1.02 units, P = 0.419) and postoperative RBC transfusion (0.24 ± 1.17 units vs. 0.46 ± 1.97 units, P = 0.306) were similar between the 2 groups, respectively. Multivariate analysis revealed no association between PFA closure time and calculated blood loss (hazard ratio, 1.06; P = 0.881). Moreover, there was no association between PFA closure time and preoperative laboratory results or assessment of tool-related liver function in multivariate analysis.

Conclusion

There was no correlation between the amount of blood loss and platelet function in patients who underwent liver resection. In patients undergoing liver resection who are not managed on antiplatelet agents or do not have chronic kidney disease, the use of routine PFA is not recommended.

The role of platelet function analyzer-200 in predicting perioperative bleeding risk

BACKGROUND/AIMS

Various preoperative screening tests, such as platelet count, prothrombin time, activated partial thromboplastin time, and bleeding time, have been widely used to evaluate the risk of bleeding during surgery. Use of platelet function analyzer (PFA)-100/200 for assessing platelet function instead of bleeding time is increasing. However, its role in predicting the perioperative risk of bleeding remains controversial.

METHODS

Data of 703 patients who underwent surgery under general anesthesia were retrospectively analyzed. Preoperative platelet function was measured using PFA-200 system and the association with intraoperative bleeding was assessed. Additionally, other variables that could affect PFA-200 results were assessed by logistic regression analysis.

RESULTS

Collagen/epinephrine (COL/EPI) test was prolonged in 199/703 (28.3%) patients (EPI group), while 99/212 (46.7%) patients showed COL/adenosine diphosphate test abnormalities. Bleeding over 300 mL during surgery occurred in 14.3% and 20.1% of patients in the normal and EPI groups, respectively (p = 0.058). In addition, red blood cell transfusion within 72 hours after surgery rate was significantly higher in the EPI group than in the normal group (31.7% vs. 23.4%, p = 0.024). In multivariate logistic analysis, prolongation closure time with COL/EPI (p = 0.068) was marginally associated with risk of bleeding during surgery. Furthermore, PFA-200 results were influenced by various factors, such as nonsteroidal anti-inflammatory drug use, blood group, hematocrit, and time of blood collection.

CONCLUSION

Preoperative PFA-200 test may be helpful in predicting the risk of perioperative bleeding. However, its results should be carefully interpreted because they are affected by several factors.

Characterization of a novel selective factor Xa inhibitor, DJT06001, which reduces thrombus formation with low risk of bleeding

Factor Xa (FXa) is a serine protease that plays key roles in linking the intrinsic and extrinsic coagulation pathways to the final common pathway. DJT06001 is an oral, highly specific and direct FXa inhibitor for the prevention and treatment of thromboembolic diseases. We characterized the compound in vitro and studied its in vivo activity in rat thrombosis models, as well as bleeding risk and Pharmacokinetics and Pharmacodynamics (PK/PD) relationship. DJT06001 inhibited free FXa with an inhibitory constant (Ki) of 0.99 nM, and exhibited >10000-fold selectivity for FXa than for other related serine proteases. DJT06001 concentration-dependently inhibited FXa activity in the prothrombinase complex with an IC₅₀ of 2.53 nM. The concentrations for DJT06001 to double the prothrombin time (PT) and activated partial thromboplastin time (APTT) were 0.74 and 0.57 μM, respectively. Importantly, DJT06001 did not impair platelet aggregation induced by ADP, platelet activating factor (PAF) and collagen. Furthermore, DJT06001 inhibited thrombus formation in rat thrombosis models in a dose dependent manner. And in rat tail bleeding risk test, it caused less bleeding than rivaroxaban at doses that achieve the same antithrombotic effect. PK/PD studies further demonstrated that there was a good correlation between the plasma concentrations of DJT06001and its inhibition of plasma FXa activity and prolongation of PT. In conclusion, DJT06001 was shown to be a potent and specific FXa inhibitor with excellent PK/PD profiles and it could be developed as a new anticoagulant for the management of thromboembolic diseases.