Baseline Risks of Venous Thromboembolism and Major Bleeding are Crucial in Decision-making on Thromboprophylaxis

Risk of thrombosis and bleeding in gynecologic cancer surgery: systematic review and meta-analysis

OBJECTIVE

This study aimed to provide procedure-specific estimates of the risk of symptomatic venous thromboembolism and major bleeding in the absence of thromboprophylaxis, following gynecologic cancer surgery.

DATA SOURCES

We conducted comprehensive searches on Embase, MEDLINE, Web of Science, and Google Scholar for observational studies. We also reviewed reference lists of eligible studies and review articles. We performed separate searches for randomized trials addressing effects of thromboprophylaxis and conducted a web-based survey on thromboprophylaxis practice.

STUDY ELIGIBILITY CRITERIA

Observational studies enrolling ≥50 adult patients undergoing gynecologic cancer surgery procedures reporting absolute incidence for at least 1 of the following were included: symptomatic pulmonary embolism, symptomatic deep vein thrombosis, symptomatic venous thromboembolism, bleeding requiring reintervention (including reexploration and angioembolization), bleeding leading to transfusion, or postoperative hemoglobin <70 g/L.

METHODS

Two reviewers independently assessed eligibility, performed data extraction, and evaluated risk of bias of eligible articles. We adjusted the reported estimates for thromboprophylaxis and length of follow-up and used the median value from studies to determine cumulative incidence at 4 weeks postsurgery stratified by patient venous thromboembolism risk factors. The GRADE approach was applied to rate evidence certainty.

RESULTS

We included 188 studies (398,167 patients) reporting on 37 gynecologic cancer surgery procedures. The evidence certainty was generally low to very low. Median symptomatic venous thromboembolism risk (in the absence of prophylaxis) was <1% in 13 of 37 (35%) procedures, 1% to 2% in 11 of 37 (30%), and >2.0% in 13 of 37 (35%). The risks of venous thromboembolism varied from 0.1% in low venous thromboembolism risk patients undergoing cervical conization to 33.5% in high venous thromboembolism risk patients undergoing pelvic exenteration. Estimates of bleeding requiring reintervention varied from <0.1% to 1.3%. Median risks of bleeding requiring reintervention were <1% in 22 of 29 (76%) and 1% to 2% in 7 of 29 (24%) procedures.

CONCLUSION

Venous thromboembolism reduction with thromboprophylaxis likely outweighs the increase in bleeding requiring reintervention in many gynecologic cancer procedures (eg, open surgery for ovarian cancer and pelvic exenteration). In some procedures (eg, laparoscopic total hysterectomy without lymphadenectomy), thromboembolism and bleeding risks are similar, and decisions depend on individual risk prediction and values and preferences regarding venous thromboembolism and bleeding.

Risk of thrombosis and bleeding in gynecologic noncancer surgery: systematic review and meta-analysis

OBJECTIVE

This study aimed to provide procedure-specific estimates of the risk for symptomatic venous thromboembolism and major bleeding in noncancer gynecologic surgeries.

DATA SOURCES

We conducted comprehensive searches on Embase, MEDLINE, Web of Science, and Google Scholar. Furthermore, we performed separate searches for randomized trials that addressed the effects of thromboprophylaxis.

STUDY ELIGIBILITY CRITERIA

Eligible studies were observational studies that enrolled ≥50 adult patients who underwent noncancer gynecologic surgery procedures and that reported the absolute incidence of at least 1 of the following: symptomatic pulmonary embolism, symptomatic deep vein thrombosis, symptomatic venous thromboembolism, bleeding that required reintervention (including re-exploration and angioembolization), bleeding that led to transfusion, or postoperative hemoglobin level <70 g/L.

METHODS

A teams of 2 reviewers independently assessed eligibility, performed data extraction, and evaluated the risk of bias of the eligible articles. We adjusted the reported estimates for thromboprophylaxis and length of follow-up and used the median value from studies to determine the cumulative incidence at 4 weeks postsurgery stratified by patient venous thromboembolism risk factors and used the Grading of Recommendations Assessment, Development and Evaluation approach to rate the evidence certainty.

RESULTS

We included 131 studies (1,741,519 patients) that reported venous thromboembolism risk estimates for 50 gynecologic noncancer procedures and bleeding requiring reintervention estimates for 35 procedures. The evidence certainty was generally moderate or low for venous thromboembolism and low or very low for bleeding requiring reintervention. The risk for symptomatic venous thromboembolism varied from a median of <0.1% for several procedures (eg, transvaginal oocyte retrieval) to 1.5% for others (eg, minimally invasive sacrocolpopexy with hysterectomy, 1.2%-4.6% across patient venous thromboembolism risk groups). Venous thromboembolism risk was <0.5% for 30 (60%) of the procedures; 0.5% to 1.0% for 10 (20%) procedures; and >1.0% for 10 (20%) procedures. The risk for bleeding the require reintervention varied from <0.1% (transvaginal oocyte retrieval) to 4.0% (open myomectomy). The bleeding requiring reintervention risk was <0.5% in 17 (49%) procedures, 0.5% to 1.0% for 12 (34%) procedures, and >1.0% in 6 (17%) procedures.

CONCLUSION

The risk for venous thromboembolism in gynecologic noncancer surgery varied between procedures and patients. Venous thromboembolism risks exceeded the bleeding risks only among selected patients and procedures. Although most of the evidence is of low certainty, the results nevertheless provide a compelling rationale for restricting pharmacologic thromboprophylaxis to a minority of patients who undergo gynecologic noncancer procedures.

Systematic Reviews and Meta-analyses of the Procedure-specific Risks of Thrombosis and Bleeding in General Abdominal, Colorectal, Upper Gastrointestinal, and Hepatopancreatobiliary Surgery

OBJECTIVE

To provide procedure-specific estimates of symptomatic venous thromboembolism (VTE) and major bleeding after abdominal surgery.

BACKGROUND

The use of pharmacological thromboprophylaxis represents a trade-off that depends on VTE and bleeding risks that vary between procedures; their magnitude remains uncertain.

METHODS

We identified observational studies reporting procedure-specific risks of symptomatic VTE or major bleeding after abdominal surgery, adjusted the reported estimates for thromboprophylaxis and length of follow-up, and estimated cumulative incidence at 4 weeks postsurgery, stratified by VTE risk groups, and rated evidence certainty.

RESULTS

After eligibility screening, 285 studies (8,048,635 patients) reporting on 40 general abdominal, 36 colorectal, 15 upper gastrointestinal, and 24 hepatopancreatobiliary surgery procedures proved eligible. Evidence certainty proved generally moderate or low for VTE and low or very low for bleeding requiring reintervention. The risk of VTE varied substantially among procedures: in general abdominal surgery from a median of <0.1% in laparoscopic cholecystectomy to a median of 3.7% in open small bowel resection, in colorectal from 0.3% in minimally invasive sigmoid colectomy to 10.0% in emergency open total proctocolectomy, and in upper gastrointestinal/hepatopancreatobiliary from 0.2% in laparoscopic sleeve gastrectomy to 6.8% in open distal pancreatectomy for cancer.

CONCLUSIONS

VTE thromboprophylaxis provides net benefit through VTE reduction with a small increase in bleeding in some procedures (eg, open colectomy and open pancreaticoduodenectomy), whereas the opposite is true in others (eg, laparoscopic cholecystectomy and elective groin hernia repairs). In many procedures, thromboembolism and bleeding risks are similar, and decisions depend on individual risk prediction and values and preferences regarding VTE and bleeding.

In-Hospital Venous Thromboembolism and Pulmonary Embolism After Major Urologic Cancer Surgery

BACKGROUND

This study aimed to test for temporal trends of in-hospital venous thromboembolism (VTE) and pulmonary embolism (PE) after major urologic cancer surgery (MUCS).

METHODS

In the Nationwide Inpatient Sample (NIS) database (2010-2019), this study identified non-metastatic radical cystectomy (RC), radical prostatectomy (RP), radical nephrectomy (RN), and partial nephrectomy (PN) patients. Temporal trends of VTE and PE and multivariable logistic regression analyses (MLR) addressing VTE or PE, and mortality with VTE or PE were performed.

RESULTS

Of 196,915 patients, 1180 (1.0%) exhibited VTE and 583 (0.3%) exhibited PE. The VTE rates increased from 0.6 to 0.7% (estimated annual percentage change [EAPC] + 4.0%; p = 0.01). Conversely, the PE rates decreased from 0.4 to 0.2% (EAPC - 4.5%; p = 0.01). No difference was observed in mortality with VTE (EAPC - 2.1%; p = 0.7) or with PE (EAPC - 1.2%; p = 0.8). In MLR relative to RP, RC (odds ratio [OR] 5.1), RN (OR 4.5), and PN (OR 3.6) were associated with higher VTE risk (all p < 0.001). Similarly in MLR relative to RP, RC (OR 4.6), RN (OR 3.3), and PN (OR 3.9) were associated with higher PE risk (all p < 0.001). In MLR, the risk of mortality was higher when VTE or PE was present in RC (VTE: OR 3.7, PE: OR  4.8; both p < 0.001) and RN (VTE: OR 5.2, PE: OR  8.3; both p < 0.001).

CONCLUSIONS

RC, RN, and PN predisposes to a higher VTE and PE rates than RP. Moreover, among RC and RN patients with either VTE or PE, mortality is substantially higher than among their VTE or PE-free counterparts.

Systematic reviews of observational studies of Risk of Thrombosis and Bleeding in General and Gynecologic Surgery (ROTBIGGS): introduction and methodology

BACKGROUND

Venous thromboembolism (VTE) and bleeding are serious and potentially fatal complications of surgical procedures. Pharmacological thromboprophylaxis decreases the risk of VTE but increases the risk of major post-operative bleeding. The decision to use pharmacologic prophylaxis therefore represents a trade-off that critically depends on the incidence of VTE and bleeding in the absence of prophylaxis. These baseline risks vary widely between procedures, but their magnitude is uncertain. Systematic reviews addressing baseline risks are scarce, needed, and require innovations in methodology. Indeed, systematic summaries of these baseline risk estimates exist neither in general nor gynecologic surgery. We will fill this knowledge gap by performing a series of systematic reviews and meta-analyses of the procedure-specific and patient risk factor stratified risk estimates in general and gynecologic surgeries.

METHODS

We will perform comprehensive literature searches for observational studies in general and gynecologic surgery reporting symptomatic VTE or bleeding estimates. Pairs of methodologically trained reviewers will independently assess the studies for eligibility, evaluate the risk of bias by using an instrument developed for this review, and extract data. We will perform meta-analyses and modeling studies to adjust the reported risk estimates for the use of thromboprophylaxis and length of follow up. We will derive the estimates of risk from the median estimates of studies rated at the lowest risk of bias. The primary outcomes are the risk estimates of symptomatic VTE and major bleeding at 4 weeks post-operatively for each procedure stratified by patient risk factors. We will apply the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to rate evidence certainty.

DISCUSSION

This series of systematic reviews, modeling studies, and meta-analyses will inform clinicians and patients regarding the trade-off between VTE prevention and bleeding in general and gynecologic surgeries. Our work advances the standards in systematic reviews of surgical complications, including assessment of risk of bias, criteria for arriving at the best estimates of risk (including modeling of the timing of events and dealing with suboptimal data reporting), dealing with subgroups at higher and lower risk of bias, and use of the GRADE approach.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42021234119.

An International Survey on the Use of Thromboprophylaxis in Urological Surgery

BACKGROUND

The use of perioperative thromboprophylaxis in urological surgery is common but not standardized.

OBJECTIVE

To characterize international practice variation in thromboprophylaxis use in urological surgery.

DESIGN, SETTING, AND PARTICIPANTS

We conducted a scenario-based survey addressing the use of mechanical and pharmacological thromboprophylaxis in urological cancer procedures (radical cystectomy [RC], radical prostatectomy [RP], and radical nephrectomy [RN]) among practicing urologists in Canada, Finland, and Japan. The survey presented patient profiles reflecting a spectrum of risk for venous thromboembolism; the respondents described their clinical practice.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The proportion of respondents who routinely used (1) mechanical, (2) pharmacological, and (3) extended pharmacological prophylaxis was stratified by procedure. A logistic regression identified characteristics associated with thromboprophylaxis use.

RESULTS AND LIMITATIONS

Of 1051 urologists contacted, 570 (54%) participated in the survey. Japanese urologists were less likely to prescribe pharmacological prophylaxis than Canadian or Finnish urologists (p < 0.001 for all procedures). Canadian and Finnish urologists exhibited large variation for extended pharmacological prophylaxis for RP and RN. Finnish urologists were most likely to prescribe extended prophylaxis versus Canadian and Japanese urologists (RC 98%, 84%, and 26%; Open RP 25%, 8%, and 3%; robotic RP 11%, 9%, and 0%; and RN 43%, 7%, and 1%, respectively; p < 0.001 for each procedure). Less variation was found regarding the prescription of mechanical prophylaxis, which was most commonly used until ambulation or discharge. The length of hospital stay was longer in Japan and may bias estimates of extended prophylaxis in Japan.

CONCLUSIONS

We found large variation in clinical practice regarding pharmacological thromboprophylaxis within and between countries. Knowledge translation of evidence-based guidelines may reduce problematic international variation in practice.

PATIENT SUMMARY

Use of medications to decrease blood clots after urological cancer surgery differs within and between countries. Closer adherence to urology guidelines addressing the prevention of blood clots may decrease this variation and improve patient outcomes.