Venous Thromboembolism: A Preventable Postoperative Peril in Gynecologic Surgery
Venous thromboembolism (VTE), encompassing deep-vein thrombosis (DVT) and its potential sequel, pulmonary embolism (PE), poses a significant postoperative risk following extensive gynecologic procedures. Without prophylaxis, DVT occurs in approximately 10-15% of patients, with nearly half progressing to PE. This condition, characterized by clot formation in the deep venous system, can lead to acute symptoms such as dyspnoea, limb swelling, erythema, and calf tenderness, and may culminate in chronic post-thrombotic syndrome. Alarmingly, PE secondary to postoperative DVT is implicated in about 40% of unexpected deaths among women recovering from gynecologic surgery, placing a substantial economic burden on healthcare systems. But here's the silver lining: these events are largely preventable through effective prophylactic strategies.
Prophylactic Strategies: A Multifaceted Approach
Evidence demonstrates that targeted prophylaxis significantly reduces VTE frequency and severity at a favorable cost. Available strategies include systemic anticoagulants, such as standard or fractionated heparin regimens, and non-pharmacological measures. The latter category features graduated compression hosiery and sequential pneumatic compression devices, which are valued for their user-friendliness, minimal complications, and virtually non-existent bleeding risks. Sequential compression is particularly advantageous when anticoagulation is contraindicated. By rhythmically inflating from the ankle to the calf, these devices mimic the muscle pump, accelerate venous return, and curb stasis-driven clot formation. And this is the part most people miss: the transition from open to endoscopic surgical techniques further diminishes thromboembolic risk due to faster ambulation and shorter hospitalization periods.
Mechanical Thromboprophylaxis: A Focus on Intermittent Pneumatic Compression
While guidelines for VTE prophylaxis, diagnosis, treatment, and management have been proposed, most studies to date have concentrated on patients with malignant gynecological diseases or the safety evaluation of gynecological surgery. Limited research has assessed hemostatic imbalance in terms of coagulation and fibrinolysis, which is crucial for guiding perioperative and postoperative management of DVT. Some studies have attempted to measure changes in hematosis parameters, but the perioperative application of mechanical thromboprophylaxis on coagulopathies, especially in gynecological benign patients undergoing minimal invasion surgery, lacks sufficient evidence of hematosis.
Study Objectives and Methodology
This study aims to examine the effect of mechanical compression on coagulation, fibrinolysis, and DVT occurrence in Chinese patients with benign gynecological conditions undergoing minimal invasive gynecological surgery. An intermittent pneumatic compression (IPC) device was applied to bilateral lower extremities to produce mechanical compression. The primary outcomes assessed for coagulation blood tests include prothrombin time (PT), international normalized ratio (INR), percentage of prothrombin time (PT%); activated partial thromboplastin time (APTT), plasma fibrinogen (FIB), plasma D-dimer (D-D), and fibrinogen degradation products (FDP), as well as the rate of DVT incidence.
Materials and Methods
This retrospective clinical study was conducted at the Department of Anesthesiology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, between January 2021 and August 2022. The study was approved by the Ethics Committee of Guangdong Provincial Hospital of Chinese Medicine. Cases were identified by searching the hospital’s Electronic Discharge Database, followed by a comprehensive review of medical documentation to collect relevant data. Inclusion criteria comprised Chinese adult female patients from Guangdong province with a diagnosis of benign gynecological disease (uterine fibroid or ovarian cysts) and indications for gynecological laparoscopic surgery. Exclusion criteria included a history of thrombotic disease, leg ulcer, peripheral vascular disease, blood coagulation disorders, malignant gynecological tumors, cancer treatment, anticoagulant use, smoking, recent long-trip travel, acute medical illness, recent surgery, or lack of civil capacity. Patients who received standard minimally invasive gynecological surgery were recorded and divided into a Device group and a Non-device group based on the application of IPC during intraoperative and perioperative nursing care.
Application of the DVT Device
In the Device group, the Phlebo Press® DVT device was applied to the lower limbs, delivering standard pneumatic compression therapy with circumferential, sequential, gradient compression according to the manufacturer's instructions. Bilateral calf-ankle mechanical pneumatic compression began intraoperatively and was continuously monitored for half an hour postoperatively in the recovery room. Anti-thromboembolism stockings were not applied to patients to exclusively examine the effect of the mechanical compression method.
Gynecological Laparoscopic Surgery Procedure
Preoperative instrument preparation included a gynecological laparoscopic instrument kit, ultrasonic scalpel, electrosurgery, laparoscopic system, and lithotomy stand. Endotracheal intubation anesthesia was administered, and the perineum and abdominal skin were disinfected. An arc-shaped incision was made below the umbilicus, followed by the establishment of an artificial pneumoperitoneum after placing the uterine manipulator. The appropriate size of cuffs was positioned, and a laparoscope was inserted into the abdomen. The patient was then placed in a lithotomy position. A lumbar puncture of pituitin was performed to contract the uterus and reduce bleeding, with vital signs closely monitored. The fibroid capsule was incised, culled, and removed, and the abdominal cavity was thoroughly flushed after suturing the uterine defect. Any damage and bleeding to abdominal organs were carefully checked before suturing the skin incision.
Blood Collection and Analysis
To examine changes in hemostasis, 2 mL of peripheral venous blood was drawn from patients into an anticoagulant before the operation and on the morning of the second day after surgery. Blood samples were collected for coagulation function testing, including PT, APTT, TT, INR, FIB, DDi, and FDP. These parameters were detected using an automated coagulation analyzer. Samples displaying visible clots were excluded from the data set. All coagulation tests were conducted within 1 hour of sampling. Coagulation methods were employed for PT, TT, and APTT, with specific test kits and reagents used for each parameter.
DVT Detection Methods
Physical examinations were performed on all patients, with a focus on monitoring signs of VTE, bleeding, breath difficulties, and symptoms of DVT such as edema, tenderness, warmth, erythema, and pain in the lower limbs. Bilateral dorsal pedis artery pulsation was also recorded. The diameter of the legs was measured to monitor swelling.
Ultrasonographic Detection of Thrombo-embolic Events
Suspected thrombo-embolic events were investigated using bilateral color-flow duplex ultrasonography. Each examination combined real-time B-mode imaging, sequential compressibility testing, and spectral Doppler analysis, scanning continuously from the groin to the ankle. Deep-venous segments interrogated included the external iliac, common and superficial femoral, profunda femoris, popliteal, peroneal, and anterior and posterior tibial veins. Superficial conduits, such as the great and small saphenous veins, were also reviewed. Spectral (pulsed-wave) Doppler was applied at selected sites to quantify flow direction and velocity profiles. All images were archived and later interpreted by a board-certified radiologist, who documented thrombus location, morphology, and hemodynamic impact.
Treatment Protocols
Pharmacological thromboprophylaxis was administered to patients diagnosed with acute DVT in the postoperative stage. Anticoagulation treatments included subcutaneous injections of adroparin calcium and enoxaparin sodium, followed by oral rivaroxaban. All patients were closely observed for symptomatic thromboembolism for at least three months.
Statistical Analyses
General conditions, complications, treatments, and laboratory coagulation parameters were collected as clinical data. Statistical analysis was performed using GraphPad Prism. Measurement data were expressed as mean ± standard deviation. Paired t-tests were used to determine differences in coagulation parameters between pre- and post-operation within the Device and Non-device groups. An unpaired t-test was employed to compare the ratio of each parameter between the two groups using the nonparametric Mann-Whitney test. A p-value < 0.05 was considered statistically significant.
Results and Findings
The study included 119 Chinese adult female patients with benign gynecological diseases who underwent minimally invasive gynecological laparoscopy, with 62 patients in the Device group and 57 in the Non-device group. Basic demographic data revealed no significant age differences between the groups. Significant changes in coagulation parameters were observed post-operation, with PT and INR increasing and PT% and TT decreasing in both groups. However, the Device group exhibited smaller increases in PT and INR and a smaller decrease in PT% compared to the Non-device group, suggesting that IPC tempered surgery-induced coagulation changes.
DVT Incidence and Ultrasonographic Findings
Ultrasound images revealed a low incidence of DVT in both groups, with 3.3% in the Non-device group and 3.2% in the Device group. All detected thrombi were located in the distal lower limbs, with no extension to proximal segments or pulmonary emboli observed. Representative cases in both groups demonstrated thrombus formation in various lower limb veins, as confirmed by venous ultrasound imaging.
Discussion and Implications
The study demonstrated that IPC application around the time of minimally invasive gynecologic surgery influenced hemostatic shifts and thrombus formation in women with benign diseases. Surgical intervention alone induced changes in coagulation and fibrinolytic parameters, but IPC mitigated these effects, particularly in PT, INR, and FDP. The incidence of distal DVT remained low in both groups, suggesting that IPC can reduce surgery-induced activation of coagulation and fibrinolysis. However, the study's limitations include a small cohort size and the need for larger-scale, multi-center studies. Controversially, the lack of randomization in group assignment and the exclusion of certain potential VTE factors may impact the generalizability of the findings. Future research should explore the correlation between hemostatic parameters and DVT occurrence in both benign and malignant gynecological patients, as well as the effects of combined prophylaxis methods.
Conclusion
In this retrospective cohort study, peri-operative IPC mitigated surgery-induced changes in coagulation and fibrinolytic parameters and produced a numerically equal distal DVT rate in Chinese women undergoing benign gynecologic laparoscopy. These findings suggest that mechanical calf-ankle compression can attenuate early coagulation/fibrinolytic activation, although it did not significantly lower overall DVT incidence in this low-risk population. Prospective, adequately powered trials are necessary before recommending IPC as stand-alone prophylaxis in minimally invasive gynecologic surgery. Thought-provoking question: Given the study's limitations and the low DVT incidence in both groups, should IPC be considered a standard prophylactic measure in minimally invasive gynecologic surgery, or are further studies needed to establish its efficacy and generalizability?
