Intraoperative objective evaluation of venous congestion in deep epigastric artery perforator flap breast reconstruction: A pilot study

A systematic review of the scientific evidence of venous supercharging in autologous breast reconstruction with abdominally based flaps

BACKGROUND

Abdominally based free flaps are commonly used in breast reconstruction. A frequent complication is venous congestion, which might contribute to around 40% of flap failures. One way to deal with it is venous supercharging. The primary aim of this study was to investigate the scientific evidence for the effects of venous supercharging.

METHODS

A systematic literature search was conducted in PubMed, CINAHL, Embase, and Cochrane library. The included articles were critically appraised, and certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach.

RESULTS

Thirty-six studies were included. Most studies had serious study limitations and problems with directness. Three studies report 'routine' use of venous supercharging and performed it prophylactically in patients who did not have clinical signs of venous congestion. Seventeen studies report on flap complications, of which one is a randomised controlled trial demonstrating statistically significant lower complication rates in the intervention group. The overall certainty of evidence for the effect of a venous supercharging on flap complications, length of hospital stay and operative time, in patients without clinical signs of venous congestion, is very low (GRADE ⊕ ⊕ ⊝ ⊝), and low on and surgical takebacks (GRADE ⊕ ⊕ ⊝ ⊝). Twenty-one studies presented data on strategies and overall certainty of evidence for using radiological findings, preoperative measurements, and clinical risk factors to make decisions on venous supercharging is very low (GRADE ⊕ ⊝ ⊝ ⊝).

CONCLUSION

There is little scientific evidence for how to predict in which cases, without clinical signs of venous congestion, venous supercharging should be performed. The complication rate might be lower in patients in which a prophylactic venous anastomosis has been performed.

TRIAL REGISTRATION

PROSPERO (CRD42022353591).

Utility of the intraflap perfusion procedure for abdominal free flap in unilateral breast reconstruction

BACKGROUND

Heparin prophylaxis for venous thromboembolism can be used in microsurgery. If vein anastomosis is performed before the artery, heparin irrigation into the artery can be performed locally without systematic effect. This study aimed to introduce this "intraflap perfusion procedure" in autologous breast reconstruction.

METHODS

Among the 220 patients with unilateral breast cancer who had received the free abdominal flap, we retrospectively compared those that had undergone the intraflap perfusion procedure (n = 108) and those who did not (n = 112). A 10 mL injection of heparinized physiological saline solution (100 units/mL) was administered into the deep inferior epigastric artery. Intraflap perfusion was performed before, during, and after vein anastomosis, without the vessel clip of the vein. Artery anastomosis was performed without the use of a vein clamp. Further, vein anastomosis was performed tightly to prevent leakage from the vein anastomosis site during artery anastomosis.

RESULTS

The rates of superficial inferior epigastric vein (SIEV) superdrainage (18.5% vs. 42.0%, P < 0.001), and intraoperative flap congestion (0.9% vs. 8.0%, P = 0.01) were significantly lower in patients undergoing this procedure. There were no significant differences regarding other factors (age, BMI, laterality, comorbidities, and other operative details).

CONCLUSIONS

Intraflap perfusion prevented long-term stasis at the venous anastomosis site and capillary level. It could reduce flap congestion. SIEV superdrainage was performed to manage flap congestion, particularly in patients who did not undergo this procedure. Consequently, it can be inferred that this procedure reduces the rate of superdrainage.

The correlation of flap blood glucose with fat necrosis of free abdominal flap for unilateral breast reconstruction

BACKGROUND

Flap blood glucose (FBG) measurement is proposed as a monitoring technique. A cause of long-lasting fever could be derived from fat necrosis. If the findings of low FBG correlated with fat necrosis, it could predict the poor cosmetic result and a source of fever. However, this correlation remained unsolved. The purpose of this study was to clarify this correlation in breast reconstruction.

METHODS

In the 180 unilateral breast cancer patients (mean age = 49.8 years) performed free abdominal flap, we retrospectively compared the group where fat necrosis occurred with the group where it did not occur (45 patients with fat necrosis vs. 135 patients without). We compared the average of FBG in each postoperative day.

RESULTS

The average FBG was significantly lower in patients with fat necrosis in the second postoperative day (115.3 ± 27.3 vs. 126.3 ± 13.7 mg/dl, p = .026) and the third postoperative day (111.1 ± 22.1 vs. 118.8 ± 13.8 mg/dl, p = .036). Mean BMI and inserted total flap weight were significantly higher in patients with the fat necrosis group (24.8 vs. 22.9 kg/m² , p = .005) (617 vs. 478 g, p = .006). The multivariate analysis revealed early FBG (OR = 0.96, p = .0002) and laterality (right side) (OR = 0.46, p = .043) were independently significant predictors. There were no significant between-group differences regarding other factors (age, systemic blood glucose, comorbidities and operative details).

CONCLUSIONS

The possibility of fat necrosis was high for patients with low FBG in the early postoperative day.

Predicting the Feasibility of Utilizing SIEA Flap for Breast Reconstruction with Preoperative BMI and Computed Tomography Angiography (CTA) Data

BACKGROUND

Diameters greater than 1.5 mm are considered one of the generally accepted criteria for utilizing superficial epigastric artery (SIEA) flaps for breast reconstruction. However, this standard fails to consider individual differences among patients or deep inferior epigastric perforator (DIEP) perfusion of the same angiosome as the SIEA. This study combined the SIEA system with the DIEP system and explored the relationship between the two systems and body mass index (BMI) to theoretically provide a reference for flap choice in the preoperative surgical plan.

METHODS

This study analysed preoperative computed tomography angiography (CTA) data from patients who received systematically postoperative treatment for unilateral breast cancer and were scheduled for breast reconstruction from 2013 to 2018 in our centre. All patients included had no past medical history that might have influenced the diameter of the SIEA, and their CTA data showed the presence of SIEA.

RESULTS

Twenty-five females with a mean BMI of 23.6 ± 3.3 kg/m² were included. A total of 30 hemi-abdomens identified with the SIEA were assessed. The measured mean diameter of the SIEA was 1.63 ± 0.55 mm, showing a highly linear correlation with BMI (r = 0.73, p < 0.001), while the maximum diameter of the deep inferior epigastric perforator (DIEPmax) and the number of dominant perforators originating from the deep inferior epigastric artery (DIEA) were not related to BMI. It was analysed from the equation between the calibre of the SIEA and BMI that when the BMI was greater than or equal to 24 kg/m², the minimum diameter of the SIEA was at least 1.5 mm; when the BMI was 25 kg/m², the diameter of the SIEA was, at most, 2.0 mm. Based on the linear correlation described above, we proposed that if the diameter of the SIEA was greater than or equal to 2.0 mm, a BMI ≥ 25 kg/m² could be fully guaranteed. In terms of the advantageous single pedicle for reconstruction, the ratio of the SIEA diameter to DIEPmax (SIEA/DIEPmax) showed a significant linear correlation with BMI (r = 0.82, p < 0.001), and when the BMI was greater than or equal to 25 kg/m², the lower limit of its predicted value was above 1.0; in other words, the SIEA diameter was advantageous compared with DIEPmax for the use of a single pedicle. In terms of perfusion, the SIEA system was positively correlated with BMI (p < 0.001), while the DIEP system was not. The difference in perfusion level between the SIEA and DIEP systems showed a positive correlation with BMI (p = 0.001), while the sum of the two systems only tended to be correlated, without statistical significance (p = 0.06).

CONCLUSIONS

For patients with a BMI ≥ 25 kg/m² or an SIEA diameter ≥ 2.0 mm, application of an SIEA flap is theoretically a preferable choice in preoperative surgical planning for breast reconstruction. And the patients should meet two conditions: the first one is the absence of past medical history that might potentially influence the diameter of the SIEA; the second is the presence of the SIEA, which has already been shown by the preoperative imaging data. Through perfusion-related studies, we propose that the SIEA is likely a compensatory vessel that is inclined to present in people with larger BMIs.

LEVEL OF EVIDENCE IV

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Different Hydraulic Constructs to Optimize the Venous Drainage of DIEP Flaps in Breast Reconstruction: Decisional Algorithm and Review of the Literature

BACKGROUND

 Venous congestion is the most common perfusion-related complication of deep inferior epigastric artery perforator (DIEP) flap. Several hydraulic constructs can be created for venous superdrainage in case of flap venous engorgement or as a preventive measure. These can be classified based on the choice of the draining vein of the flap, either a second deep inferior epigastric vein (DIEV) or a superficial inferior epigastric vein (SIEV), and of the recipient vein, either a vein of the chest or the DIEV.

METHODS

 We conducted a comprehensive systematic literature review in Medline, Scopus, EMBASE, Cochrane Library, and Google Scholar to find publications that reported on venous congestion in DIEP flap. The keywords used were DIEP Flap, breast reconstruction, venous congestion, supercharging, superdrainage, SIEV, and DIEV.

RESULTS

 Based on the studies found in the literature, we developed an algorithm to guide the surgeon's decision when choosing the veins for the superdrainage anastomosis.

CONCLUSION

 Several alternatives for venous anastomosis in superdrainage are available. We propose an algorithm to simplify the choice. The use of the ipsilateral SIEV to be connected to a vein of the chest appears to be advantageous. The anatomical position that allows the easiest anastomosis dictates which chest vein to favor.