Abstract
Background:
Microsurgical thrombosis is a critical complication of free flap surgery. Evidence evaluating the efficacy of intraoperative thromboprophylaxis in mitigating this complication during deep inferior epigastric perforator (DIEP) flap breast reconstruction remains limited. Here, we report a retrospective analysis of all DIEP flap breast reconstructions performed at our institution during a 6-year period.
Methods:
This single-center analysis offers a retrospective review of all female patients who underwent DIEP flap breast reconstruction from January 2018 to June 2024. Subjects were divided into 2 groups: a control group and a treatment group that received an intraoperative bolus administration of 2000 IU of unfractionated heparin (UFH). Patient characteristics, therapeutic variables, intraoperative details, and postoperative outcomes were extracted and analyzed. Postoperative complications were classified into subgroups: acute complications (≤4 d) and delayed complications (>4 d).
Results:
This study included 114 patients (141 breasts), corresponding to 48 patients in the control cohort and 66 patients in the UFH cohort. No significant differences were observed in the occurrence of complications in intraoperative (P = 0.226), acute (P = 0.839), or delayed settings (P = 1.00). Notably, the risk of thrombosis and hematoma was comparable. Interestingly, ischemia time and total operative duration were significantly prolonged in the control group (P < 0.05).
Conclusions:
Intraoperative anticoagulant prophylaxis using UFH did not diminish acute thrombotic complications; however, it was also not associated with an increased risk of hematoma and bleeding. These findings offer valuable insights regarding the clinical relevance and safety profile of perioperative UFH administration.
Takeaways
Question: Does intraoperative heparin administration reduce postoperative complications in deep inferior epigastric perforator flap breast reconstruction?
Findings: Intraoperative anticoagulant prophylaxis with unfractionated heparin did not reduce the incidence of acute thrombotic events, nor was it associated with an increased risk of hematoma or bleeding.
Meaning: These findings indicate that the thromboprophylactic regimen under investigation neither alters the incidence of intraoperative or postoperative thrombotic events nor confers an elevated risk of hemorrhagic complications.
INTRODUCTION
With more than 2 million new cases estimated for 2025, breast cancer represents a significant challenge in today’s healthcare system.1 For patients undergoing therapeutic or prophylactic mastectomy, subsequent breast reconstruction using autologous tissue is generally preferred.2–4
Although the deep inferior epigastric perforator (DIEP) flap is widely recognized as the gold standard for breast reconstruction, this procedure carries drawbacks that require careful consideration.5 Thrombotic complications, in particular, can have critical consequences for flap survival and the system as a whole.6 Indeed, the DIEP flap has an increased risk of thrombotic events compared with other operations in plastic surgery due to factors such as cancer history, immunosuppression, long operative times, and other patient-specific and procedure-related risks.6,7 When combined with intraoperative thrombotic complications, these factors represent a substantial barrier to successful microsurgical reconstruction and constitute the leading causes of microvascular free tissue transfer failure. In fact, the literature describes a 1%–5% free flap failure rate as a result of thrombosis at the anastomosis site.8,9
Nonetheless, perioperative anticoagulation prophylaxis must be well balanced. Although crucial in microsurgical procedures, it has been associated with an increased risk of bleeding and hematomas.10 Over the 50 years that unfractionated heparin (UFH) has been in clinical use, its appropriate usage in the context of breast reconstruction has been widely debated.11 Whereas preoperative and postoperative anticoagulation prophylaxis analyses are now well documented,6,12–14 there is a paucity of research investigating intraoperative heparin administration for DIEP flap breast reconstructions to address the operational risk of microsurgical thrombosis. We hypothesize that the intraoperative administration of a UFH bolus (2000 UI) can reduce microsurgical complications and improve reconstructive outcomes.
Hence, in this study, we report a retrospective analysis comparing intraoperative and postoperative microsurgical outcomes and complications of patients who received an intraoperative UFH bolus, compared with those who did not receive this intervention.
METHODS
In this single-center analysis, we retrospectively reviewed the medical charts of all female patients who underwent DIEP flap breast reconstruction from January 2018 to June 2024, with approval from the relevant ethics committee (ID: 2025-00534).
Subjects
Patients were included if they underwent prophylactic or therapeutic mastectomy followed by immediate or delayed DIEP flap breast reconstruction. We excluded patients whose surgery was performed using intraoperative anticoagulation prophylaxis other than the injection of a 2000 IU Liquemin (UFH) bolus at the end of ischemia time. Subjects were divided into 2 groups: a control group and a treatment group receiving intraoperative UFH administration. Forty milligrams of enoxaparin was administered to all patients in the sixth postoperative hour, followed by once daily for a duration of 1 month. Informed consent was obtained from all included patients.
Definition of Parameters
We documented demographic data such as age, body mass index (BMI), active smoking status, hypertension, diabetes, coagulopathies, and American Society of Anesthesiologists scores on a per-patient basis. Preoperative data regarding neoadjuvant chemotherapy, radiotherapy, or endocrine therapy, and intraoperative data such as operative time, flap ischemia time, flap weight, number of perforators, intraoperative and postoperative complications, as well as administration of UFH, were collected on a per-breast basis. Complications regarding the donor site were evaluated on a per-patient basis.
Evaluation of Outcomes
The evaluation of microsurgical intraoperative and postoperative complications, such as hematoma formation and thrombotic events, constituted the primary outcomes of our study. Postoperative complications were classified into 2 subgroups: acute, appearing within 4 days after surgery, and delayed, occurring after 4 days. Although some authors adopt a 3-day cutoff to define the acute complication timeframe,15,16 our institutional protocol mandates careful monitoring of the flap for up to 4 days postoperatively. Hence, we adopted a 4-day cutoff for acute complications. Secondary outcomes of this study included donor-site and recipient-site complications such as skin necrosis, fat necrosis, wound dehiscence, seroma, infection, partial flap loss, and total flap loss.
Statistical Analysis
The documented patient data were transferred to the GraphPad Prism software platform, version 10.4.2. We reported continuous variables as mean ± SD, whereas categorical variables were summarized as frequencies and percentages. The Shapiro–Wilk test was performed to verify the assumption of normality. Patients were compared using the 2-tailed t test and the Mann-Whitney test. A 2-sided Fischer exact test was used when analyzing categorical variables. To account for potential confounders and to assess the independent effect of UFH, binary logistic regression analysis was performed for categorical variables, and linear regression analysis for continuous variables. The statistical significance was set at a P value of less than 0.05.
Power Analysis
A post hoc power analysis of 141 patients with an α of 0.05 showed t test powers of 21%, 84%, and 99% for small (d = 0.2), medium (d = 0.5), and large (d = 0.8) effects, and Fisher exact-test power of 22%, 94%, and more than 99% for small (w = 0.1), medium (w = 0.3), and large (w = 0.5) effects. The study is thus well powered for clinically meaningful medium-to-large differences, but remains limited for small effects.
RESULTS
Baseline Characteristics
A total of 114 patients were included, corresponding to 141 DIEP flap breast reconstructions: 64 flaps (45.4%) in the control group and 77 flaps (54.6%) in the UFH group. The age difference between patients who did not receive UFH, with a mean age of 49.8 years (SD 8.0 y), and patients who received UFH, with a mean age of 50.4 years (SD 9.6 y), was not statistically significant (P = 0.933). There were no significant differences in BMI between the control group, with a mean of 27.3 (SD 4.7) kg/m2, and the UFH group, with a mean of 26.4 (SD 3.9) kg/m2 (P = 0.300). The American Society of Anesthesiologists scores were also comparable (P = 0.201). Thirty-five percent of the control group underwent immediate reconstruction, versus 1% in the UFH group, representing a statistically significant difference (P < 0.001). Thirty-three percent of the control group underwent bilateral reconstruction, versus 15% in the UFH group, representing a statistically significant difference (P = 0.047). There were no significant differences in potential risk factors, such as smoking status (P > 0.999), hypertension (P = 0.603), diabetes (P = 0.422), or coagulopathy (P = 0.508).
Adjuvant Therapies
The proportion of patients who underwent radiotherapy did not differ significantly between the 2 groups (P = 0.080). In a similar fashion, the 2 groups were also comparable in chemotherapy rates (P > 0.999) and hormone therapy rates (P = 0.059).
Operative Variables
The procedures for the control group were performed by an average of 4.8 surgeons (including trainees and attending surgeons), compared with an average of 5.4 surgeons for the UFH group, representing a statistically significant difference (P = 0.009). The operative time for the control group was significantly longer, with a mean of 567.2 minutes (SD 123.4 min), compared with the UFH group, with a mean of 461.8 minutes (SD 118.5 min) (P < 0.001). Similarly, the ischemia time was also significantly lower for the UFH group, with a mean of 81.7 minutes (SD 32.31 min), compared with the control group, with a mean of 108.4 minutes (SD 27.05 min) (P < 0.001). Both the control group and the UFH group had an average of 2.3 perforators per DIEP flap (SD 0.770 and 1.176, respectively) (Table 1).
Table 1.
Patient Baseline Characteristics, Operative Details, and Comorbidities
| N = 114 | Control Group | Study Group | P |
|---|---|---|---|
| n = 48 | n = 66 | ||
| Age, y, mean (SD) | 49.8 (8.0) | 50.1 (9.6) | 0.933 |
| BMI, kg/m2, mean (SD) | 27.3 (4.7) | 26.4 (3.9) | 0.186 |
| ASA score, mean (SD) | 2 (0.2) | 1.9 (0.2) | 0.201 |
| Comorbidities, n (%) | |||
| Active smoker | 12 (25.00) | 16 (24.20) | 1.00 |
| Hypertension | 6 (12.50) | 11 (16.70) | 0.603 |
| Coagulopathy | 0 (0.00) | 2 (1.80) | 0.508 |
| Diabetes mellitus | 1 (2.10) | 0 (0.00) | 0.421 |
| Neoadjuvant therapy, n (%) | |||
| Radiotherapy | 14 (29.20) | 31 (47.00) | 0.08 |
| Chemotherapy | 28 (53.90) | 36 (54.60) | 1.00 |
| Hormonal therapy | 21 (43.80) | 41 (62.10) | 0.059 |
| Immediate/delay reconstruction, n (%) | |||
| Immediate | 17 (35.42) | 1 (1.52) | <0.001* |
| Delayed | 31 (64.58) | 65 (98.48) | |
| Unilateral/bilateral mastectomy, n (%) | |||
| Unilateral | 32 (66.67) | 56 (84.85) | 0.026* |
| Bilateral | 16 (33.33) | 10 (15.15) | |
| Operation time, min, mean (SD) | 567.2 (132.40) | 461.8 (118.50) | <0.001* |
| Ischemia time, min, mean (SD) | 108.4 (27.10) | 81.7 (32.30) | <0.001* |
| Intraoperative complications, n (%) | 6 (12.50) | 4 (6.10) | 0.318 |
| Postoperative length of stay, d, mean (SD) | 8.9 (3.0) | 9.6 (3.5) | 0.221 |
P < 0.05.
ASA, American Society of Anesthesiologists.
Complications
There were no statistically significant differences in intraoperative incidence rates of hematoma (P = 1.00) or thrombosis (P = 1.00). The total intraoperative complication rates between the 2 groups were comparable (P = 0.226); we observed 1 case of arterial thrombosis (1.6%), 3 cases of operative pedicle lesion (4.7%), and 3 cases of perioperative anemia (4.7%) in the control group, compared with 1 case of pedicle thrombosis (1.3%), 1 case of hematoma (1.3%), and 2 cases of operative pedicle lesion (2.6%) in the UFH group.
Postoperative complications did not statistically differ between the 2 groups, with comparable rates of hematoma (P = 0.300) and thrombotic events (P = 1.00). In the control group, there were 2 cases of hematoma (3.1%) compared with 7 cases of hematomas (9.1%) in the UFH group. There was one case of arterial thrombosis (1.6%) in the control group, compared with 2 cases in the treatment group (2.6%), as well as one case of venous thrombosis in the UFH group. The arterial thromboses led to a bilateral partial flap loss in the treatment group and total flap loss in the control group (Table 2).
Table 2.
Intraoperative, Acute, and Delayed Complications
| N = 141 | Control Group | Study Group | P |
|---|---|---|---|
| n = 64 | n = 77 | ||
| Intraoperative complications, n (%) | |||
| No complication | 57 (89.06) | 73 (94.81) | 0.226 |
| ≥1 complication | 7 (10.94) | 4 (5.19) | |
| Acute bleeding | 0 (0.00) | 1 (1.30) | 1.00 |
| Thrombosis | 1 (1.56) | 1 (1.30) | 1.00 |
| Anemia | 3 (4.69) | 0 (0.00) | 0.091 |
| Pedicle lesion | 3 (4.69) | 2 (2.60) | 0.659 |
| Acute complications, n (%) | |||
| No complication | 51 (79.69) | 60 (77.92) | 0.839 |
| ≥1 complication | 13 (20.31) | 17 (20.08) | |
| Seroma | 2 (3.13) | 1 (1.30) | 0.590 |
| Hematoma | 2 (3.13) | 6 (7.79) | 0.292 |
| Wound infection | 0 (0.00) | 1 (1.30) | 1.00 |
| Wound dehiscence | 1 (1.56) | 1 (1.30) | 1.00 |
| Partial skin necrosis | 4 (6.25) | 2 (2.60) | 0.411 |
| Thrombosis | 1 (1.56) | 2 (2.60) | 1.00 |
| Fat necrosis | 1 (1.56) | 0 (0) | 0.454 |
| Venous congestion | 1 (1.56) | 2 (2.60) | 1.00 |
| Total flap loss | 1 (1.56) | 0 (0.00) | 0.454 |
| Partial flap loss | 0 (0.00) | 2 (2.60) | 0.501 |
| Delayed complications, n (%) | |||
| No complication | 58 (90.63) | 69 (89.61) | 1.00 |
| ≥1 complication | 6 (9.38) | 8 (10.39) | |
| Seroma | 1 (1.56) | 1 (1.30) | 1.00 |
| Hematoma | 0 (0.00) | 1 (1.30) | 1.00 |
| Wound infection | 0 (0.00) | 0 (0.00) | 1.00 |
| Wound dehiscence | 1 (1.56) | 1 (1.30) | 1.00 |
| Partial skin necrosis | 3 (4.69) | 1 (1.30) | 0.619 |
| Thrombosis | 0 (0.00) | 1 (1.30) | 1.00 |
| Fat necrosis | 0 (0.00) | 1 (1.30) | 1.00 |
| Total flap loss | 0 (0.00) | 1 (1.30) | 1.00 |
| Partial flap loss | 0 (0.00) | 1 (1.30) | 1.00 |
The incidence rate of other complications was also statistically comparable. This encompasses the occurrence of skin necroses (P = 0.186), partial flap losses (P = 0.251), infections (P = 0.613), seromas (P = 0.659), wound dehiscence (P = 1.00), venous congestion (P = 1.00), and fat necrosis (P = 1.00) (Table 3).
Table 3.
Overall Postoperative Complications
| N = 141 | Control Group | Study Group | P |
|---|---|---|---|
| n = 64 | n = 77 | ||
| No complication, n (%) | 45 (70.31) | 52 (67.53) | 0.855 |
| ≥1 complication, n (%) | 19 (29.69) | 25 (32.47) | |
| Breast recipient site, n (%) | |||
| Seroma | 3 (4.69) | 2 (2.60) | 0.659 |
| Hematoma | 2 (3.13) | 7 (9.09) | 0.303 |
| Wound infection | 1 (1.56) | 2 (2.60) | 0.613 |
| Wound dehiscence | 2 (3.13) | 2 (2.60) | 1.00 |
| Partial skin necrosis | 7 (10.94) | 3 (3.90) | 0.186 |
| DIEP flap, n (%) | |||
| Thrombosis | 1 (1.56) | 2 (2.60) | 1.00 |
| Fat necrosis | 1 (1.56) | 1 (1.30) | 1.00 |
| Venous congestion | 1 (1.56) | 2 (2.60) | 1.00 |
| Total flap loss | 1 (1.56) | 1 (1.30) | 1.00 |
| Partial flap loss | 0 (0.00) | 3 (3.90) | 0.251 |
Subgroup analysis corroborated the primary findings, revealing no statistically significant differences in acute postoperative complications, with comparable rates of hematoma (P = 0.29) and thrombosis (P = 1.0). In the control group, there were 2 cases of hematoma (3.1%) and 1 case of arterial thrombosis (1.6%) versus 6 cases of hematomas (7.8%) and 2 cases of arterial thrombosis (2.6%) in the group treated with UFH. The incidence rate of other complications was also comparable. A similar trend was observed in the delayed subgroup, with no statistically significant differences in the rate of hematoma (P = 1.00), thrombosis (P = 1.00), or any other delayed complications.
Regarding postoperative anticoagulation, 1 patient with a body weight of more than 100 kg received 60 mg enoxaparin, and another patient with a hemorrhagic diathesis received 20 mg. The 2 patients were free of microsurgical complications. As for the occurrence of returns to the operating room, no significant differences were noted between the control group and the UFH group (P = 0.39).
There were no significant differences between the 2 groups in the incidence of donor-site complications, including hematoma (P = 0.63) or any other complication: wound dehiscence (P = 1.00); skin necrosis (P = 0.35); infection (P = 0.57); seroma (P = 1.00); and donor-site hernia (P = 4.21). All recipient- and donor-site complications were effectively addressed and resolved.
The mean hospitalization duration was slightly shorter for control patients, at 8.88 days (SD 3 d) versus 9.63 days (SD 3.51 d) for patients treated with UFH. The difference, however, was not statistically significant (P = 0.22).
Logistic Regression
To study the impact of confounding factors on the occurrence of complications, a multivariate analysis in the form of linear or binary regression was performed. These analyses showed that the occurrence of complications increases with BMI (odds ratio = 1.106; 95% confidence interval, 1.005–1.223; P = 0.041) (Table 4).
Table 4.
Multivariate Analysis for Total Complication Occurrence
| N = 114 | Odds | 95% CI | P |
|---|---|---|---|
| Age, y | 1.01 | 0.964–1.057 | 0.067 |
| BMI, kg/m2 | 1.11 | 1.005–1.223 | 0.041* |
| Active smoker | 1.3 | 0.498–3.226 | 0.581 |
| Hypertension | 1.49 | 0.472–4.341 | 0.474 |
| Diabetes | 1.15 | 0.693–1.343 | 0.991 |
| Radiotherapy | 1.83 | 0.797–4.213 | 0.153 |
| Chemotherapy | 1.44 | 0.629–3.083 | 0.505 |
| Hormonotherapy | 1.24 | 0.583–3.083 | 0.505 |
| Oncological mastectomy | 0.89 | 0.32–2.742 | 0.833 |
| Operation time | 1 | 0.998–1.004 | 0.553 |
P < 0.05.
CI, confidence interval.
DISCUSSION
The most critical step during free flap reconstruction is microsurgical anastomosis; any intraoperative or postoperative disruption of flap irrigation may result in partial or total flap loss. Manipulation of blood vessels when performing anastomosis exposes subendothelial tissue, which activates platelets, subsequently triggering the coagulation cascade and sharply increasing the risk of blood clot formation. Although relatively rare, flap failure is highly morbid and can be psychologically devastating to patients when it occurs.17 A national survey was conducted in Canada to capture current practices in anticoagulation therapy and protocol design. The survey was distributed to plastic surgeons, ENT surgeons, and hematologists. Among the plethora of anticoagulants, UFH and low-molecular-weight heparin (LMWH) were identified as the most commonly used prophylactic agents, regardless of administration timing.18
To our knowledge, this is the first study comparing the postoperative outcomes and complications of patients receiving intraoperative bolus administration of UFH with those of control patients during DIEP breast reconstruction. During the study period, operative practices evolved following institutional updates, resulting in the routine use of intraoperative heparin in all later cases. This process resulted in a natural separation of the 2 groups. We defined the observation window for acute complications as 4 days, corresponding to the typical duration of in-hospital stay and monitoring. Based on our current data, we can assume comparable effects on complication occurrence in all intraoperative, acute, and delayed settings for thrombosis (P = 1.0, P = 1.0, P = 1.0, respectively), as well as hematoma (P = 1.0, P = 0.29, P = 1.0).
A similar result was observed in a study reviewing systemic anticoagulant use in 517 free flap procedures by Kroll et al.19 In this study, the authors separated the patients into 5 groups, among which 1 received 5000 units of intraoperative UFH and no further postoperative anticoagulant therapy. They observed no statistically significant differences in outcomes and complications between this group and their control group with no anticoagulation.19 Although the authors attributed their lack of statistical significance partially to their high statistical standards and encouraged further study to elucidate the clinical relevance of anticoagulation benefits, the results from the systematic review and meta-analysis by Dawoud et al20 also echo our findings. The authors performed a cumulative analysis of outcomes and complications of 3531 free flaps performed in the head and neck region, with perioperative systemic anticoagulation as the intervention. Multiple thromboprophylactic options were included in their intervention group, and the differences in perioperative thrombosis, partial or total flap failure, as well as thromboembolic events between the control group and all anticoagulated groups were comparable. Other studies also concur with the results observed.21–23
Nonetheless, a retrospective review of 183 free flap reconstructions for the upper extremities observed that the control patients had a statistically significantly higher rate of major complications, including arterial and venous flap thrombosis, and that intraoperative bolus administration of 500–1000 IU UFH had the lowest complication rate.24 Interestingly, in contrast to our findings, Dawoud et al20 found that free flap complications were consistently increased for their UFH cohort. Nevertheless, it should be noted that the quantity of UFH administered in the selected studies ranged from 5000 to 25,000 IU, compared with the 2000 IU used in our study. In other words, we can observe a certain heterogeneity in the posology of different intraoperative anticoagulation regimens, making the interpretation of these results complex.
In this retrospective review, the intervention evaluated was the intraoperative administration of 2000 IU UFH. Several anticoagulation regimens are available to prevent microsurgical complications. Alternative prophylactic options include LMWH, dextran, and aspirin.22,25–31 However, guidelines for agent selection remain contentious, with consensus proving difficult to achieve.27,28,31,32 Importantly, the molecule choice seems to be as critical a parameter as its dosage. This was notably expressed in the meta-analysis by Pan et al,31 where high doses of heparin thromboprophylaxis were associated with greater flap loss rates compared with low-dose therapy. However, it should be noted that this comparison includes only 2 studies. In the first study, a UFH bolus of 2000–3000 IU was compared with 5000 IU (high dose), whereas in the second, the injection of 2500 IU (low dose) was compared with 5000 IU (high dose) of delteparin.
Additionally, the timing of heparin administration may seem to be an essential component of the algorithm that must not be neglected. In our study, a 2000 IU UFH bolus was administered intravenously intraoperatively at the end of ischemic time. Because the risk of thrombosis is greatest during vascular clamping and immediately upon its release, intraoperative UFH is intended to suppress the coagulation cascade at this critical interval through potentiation of antithrombin III.10,26,33 Different prophylaxis timings have been described; notably, Mouzannar et al23 used intraoperative UFH and studied different postoperative regimens. Tamse et al27 evaluated the use of preoperative prophylactic LMWH administration.27 Nonetheless, the absence of consistent study designs and control group limits the reliability of direct comparisons across different thromboprophylaxis timings.
An unexpected finding of our study is the longer operative time and ischemia time for control patients. Elements that could lengthen the operating time for DIEP flap breast reconstructions include bilateral operations, higher BMI, greater flap weight, the inclusion of more perforators, and lower surgeon experience.4,5,34–37 In our center, all DIEP flaps are performed by experienced surgeons with the assistance of surgical trainees. However, the number of operators was significantly greater for the UFH group. Additionally, 99% of the UFH group underwent delayed reconstruction, which is associated with shorter operating times.34 Thirty-three percent of patients in the control group underwent bilateral reconstructions versus 15% in the UFH group, a statistically significant difference. These elements may have resulted in longer operative times for the control group, even though, in our study, this parameter did not lead to pronounced adverse outcomes or complications. Immediate reconstructions have been shown to present a higher risk for overall complications, especially hematoma and seroma.34,38,39 Compared with unilateral procedures, bilateral reconstructions have been associated with an increased risk of reoperation due to venous congestion, as well as total flap loss.40 Particularly when combined with bilateral procedures, immediate reconstructions can be associated with longer operative times and an increase in complication risk by 16% every additional hour.34
This study possesses several limitations. First, the retrospective design invites bias and restricts the amount of data that can be extracted. For instance, patient satisfaction over time, a highly important element, could not be assessed. Second, the study retrospectively analyzed procedures performed on 114 patients over a period of 6 years; the surgeon turnover during this period implies variability in operating techniques, which could influence the outcomes of reconstruction. The limited sample size is a limitation that should be considered when interpreting conclusions related to drug use. Furthermore, the control group had a significantly higher proportion of patients with primary and bilateral reconstructions. This could have resulted in longer operating times for control patients, which are associated with greater complication rates. Finally, patients’ individual characteristics may interfere with the evaluation of healing and its interpretation. These limitations underscore the need for collaborative, randomized prospective trials to establish optimal thromboprophylaxis strategies, encompassing appropriate timing, effective dosing, and the most suitable anticoagulant choice, as we work toward enhanced patient safety and, ultimately, satisfaction.
CONCLUSIONS
In this study, we observed no statistically significant differences in morbidity and microsurgical complications between patients receiving an intraoperative 2000 IU UFH bolus and control patients undergoing DIEP flap breast reconstructions. These findings suggest that this specific thromboprophylaxis regimen does not have an impact on intraoperative and postoperative thrombosis occurrence and is not associated with an increased risk of hemorrhagic complications. As such, its use may be guided by surgeon preference. Further studies are warranted to establish clear guidelines regarding intraoperative thromboprophylaxis.
DISCLOSURE
The authors have no financial interest to declare in relation to the content of this article.
ETHICAL APPROVAL
Ethical approval for this study was obtained from the Commission Cantonale d’Ethique de la Recherche sur l’être humain (2024-01071).
Footnotes
Disclosure statements are at the end of this article, following the correspondence information.
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