The role of age in determining the effects of lipo-PGE1 infusion on immediate arterial maximal flow velocity in patients with diabetes undergoing free flap surgery for lower extremity reconstruction: A prospective observational study

Risk-Stratified Anticoagulation Protocol Increases Success of Lower Extremity Free Tissue Transfer in the Setting of Thrombophilia

BACKGROUND

Optimal perioperative thromboprophylaxis is crucial to avoid flap thrombosis and achieve high rates of microsurgical success. At the authors' institution, implementation of a risk-stratified anticoagulation (AC) protocol preliminarily showed a reduction in postoperative thrombotic events and flap loss. The authors present an updated analysis of surgical outcomes using risk-stratified AC in thrombophilic patients who underwent free tissue transfer (FTT) reconstruction for nontraumatic lower extremity (LE) wounds.

METHODS

The authors retrospectively reviewed patients who underwent FTT to an LE from 2012 to 2021. Their risk-stratification AC protocol was implemented in July of 2015. Low-risk and moderate-risk patients received subcutaneous heparin. High-risk patients received heparin infusion titrated to a goal partial thromboplastin time of 50 to 70 seconds. Before July of 2015, nonstratified patients were treated with either subcutaneous heparin or low-dose heparin infusion (500 U/hour). Patients were divided into two cohorts (nonstratified and risk-stratified) based on date of FTT reconstruction. Primary outcomes included rates of postoperative complications, flap salvage, and flap success.

RESULTS

Two hundred nineteen hypercoagulable patients who underwent FTT to an LE were treated with nonstratified ( n = 26) or risk-stratified ( n = 193) thromboprophylaxis. The overall flap success rate was 96.8% ( n = 212). Flap loss was lower among risk-stratified patients (1.6% versus 15.4%; P = 0.004), which paralleled a significant reduction in postoperative thrombotic events (2.6% versus 15.4%; P = 0.013). Flap salvage was accomplished more often in the risk-stratified cohort (80% versus 0%; P = 0.048). Intraoperative anastomotic revision (OR, 6.10; P = 0.035) and nonrisk stratification (OR, 9.50; P = 0.006) were independently associated with flap failure.

CONCLUSIONS

Hypercoagulability can significantly affect microsurgical outcomes. Implementation of a risk-stratified AC protocol can significantly improve flap outcomes.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Monitoring of Maximum Oxygen Intake of Breathing and Heart Rate in Exercise Training Based on Regression Equations

In order to provide a new reference method and basis for the physical testing study in healthy adults aged 40∼and 49, this paper proposes a regression equation-based monitoring study of exercise training breathing and heart rate. Sixty four subjects (30 males and 34 females), aged 40∼and 49 years, were selected. First, the subjects were screened by relevant health test and medical questionnaire to exclude the subjects with exercise contraindications and high-intensity exercise; then, the incremental load test was directly measured by gas analysis, and then, the subjects who completed the maximum oxygen intake test were tested twice, the corresponding heart rate value was recorded, and walking time were averaged for calculation. We show that the regression analysis of each index yielded regression equations and cross-validation regression equations show correlation statistics for measured and inferred maximum oxygen intake of RLOOCV = 0.826 and SEELOOCV = 0.378 (L/min). The equation can effectively speculate on the maximum oxygen intake of 40∼in healthy adults aged 49, with the advantages of efficient, low cost, fast, and convenient.

Epidural Anesthesia and Arterial Maximal Flow Velocity of Free Flap in Patients Having Microvascular Lower Extremity Reconstruction: A Randomized Controlled Trial

BACKGROUND

One of the critical factors for free flap survival is to maintain adequate perfusion. The authors evaluated the effect of epidural anesthesia on arterial maximal flow velocity of the free flap in microvascular lower extremity reconstruction.

METHODS

This is a prospective randomized study where patients were allocated to receive either combined general-epidural anesthesia (epidural group, n = 26) or general anesthesia alone (control group, n = 26). After injecting epidural ropivacaine 10 ml in the epidural group, the effect on arterial maximal flow velocity of the free flap was analyzed using ultrasonography. The primary outcome measurement was the arterial maximal flow velocity 30 minutes after establishing the baseline. Intraoperative hemodynamics and postoperative outcomes such as postoperative pain, opioid requirements, surgical complications, intensive care unit admission, and hospital length of stay were also assessed.

RESULTS

The arterial maximal flow velocity 30 minutes after the baseline measurement was significantly higher in the epidural group (35.3 ± 13.9 cm/second versus 23.5 ± 8.4 cm/second; p = 0.001). The pain score at1 hour postoperatively and opioid requirements at 1 and 6 hours postoperatively were significantly lower in the epidural group [3.0 (interquartile range, 2.0 to 5.0) versus 5.0 (interquartile range, 3.0 to 6.0), p = 0.019; 0.0 μg (interquartile range, 0.0 to 50.0 μg) versus 50.0 μg (interquartile range, 0.0 to 100 μg), p = 0.005; and 46.9 μg (interquartile range, 0.0 to 66.5 μg) versus 96.9 μg (interquartile range, 41.7 to 100.0 μg), p = 0.014, respectively]. There were no significant differences in intraoperative hemodynamics or other postoperative outcomes between the two groups.

CONCLUSION

Epidural anesthesia increased the arterial maximal flow velocity of the free flap and decreased postoperative pain and opioid requirements in microvascular lower extremity reconstruction.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, I.