The False Positive Rate of Transcutaneous Tissue Oximetry Alarms in Microvascular Breast Reconstruction Rises after 24 Hours

A Prospective Cohort Study Re-examining Tissue Oximetry Monitoring in Microsurgical Breast Reconstruction

BACKGROUND

The goal of inpatient monitoring after microsurgical breast reconstruction is to detect vascular compromise before flap loss. Near-infrared tissue oximetry (NITO) is commonly used for this purpose, but recent reports challenge its specificity and utility in current practice. Fifteen years after Keller published his initial study using this technology at our institution, we re-evaluate the role and limitations of this popular monitoring device.

METHODS

A 1-year prospective study was performed for patients undergoing microsurgical breast reconstruction and monitored postoperatively using NITO. Alerts were evaluated, and clinical endpoints relating to an unplanned return to the operating room or flap loss were recorded.

RESULTS

A total of 118 patients reconstructed with 225 flaps were included within the study. There were no cases of flap loss at the time of discharge. There were 71 alerts relating to a drop in oximetry saturation. Of these, 68 (95.8%) were deemed to be of no significance. In 3 cases (positive predictive value of 4.2%), the alert was significant, and there were concerning clinical signs apparent at that point. A sensor in an inframammary fold position was associated with nearly twice the average number of alerts as compared with areolar or periareolar positions ( P = 0.01). In 4 patients (3.4%), a breast hematoma required operative evacuation, and these cases were detected by nursing clinical examination.

CONCLUSIONS

The monitoring of free flaps after breast reconstruction through tissue oximetry shows a poor positive predictive value for flap compromise and requires clinical corroboration of alerts but missed no pedicle-related adverse events. With a high sensitivity for pedicle-related issues, NITO may be helpful postoperatively, but the exact timeframe for use must be weighed at the institutional level.

Fingerstall-type Tissue Oximetry Reduced Anxiety of Nurses in Postoperative Nursing Monitoring of Free Flaps

Postoperative free flap monitoring is essential for immediately detecting obstruction of anastomosed vessels with successive recovery surgery for salvaging flaps. We performed postoperative nursing monitoring using handheld Doppler sonography, but nurses reported feeling anxious with this approach and demanded a clear-cut evaluation method. Therefore, we implemented monitoring with the fingerstall-type tissue oximeter Toccare, a noninvasive device that enables easy flap checking by simply touching the flap with a probe.

Do Patient Expectations of Discharge Affect Length of Stay after Deep Inferior Epigastric Perforator Flap for Breast Reconstruction?

INTRODUCTION

 Deep inferior epigastric artery perforator (DIEP) flap is a common method of breast reconstruction. Enhanced recovery after surgery (ERAS) postoperative protocols have been used to optimize patient outcomes and facilitate shorter hospital stays. The effect of patient expectations on length of stay (LOS) after DIEP has not been evaluated. The purpose of this study was to investigate whether patient expectations affect LOS.

METHODS

 A retrospective chart review was performed for patients undergoing DIEP flaps for breast reconstruction from 2017 to 2020. All patients were managed with the same ERAS protocol. Patients were divided in Group I (early expectations) and Group II (standard expectations). Group I patients had expectations set for discharge postoperative day (POD) 2 for unilateral DIEP and POD 3 for bilateral DIEP. Group II patients were given expectations for POD 3 to 4 for unilateral DIEP and POD 4 to 5 for bilateral. The primary outcome variable was LOS.

RESULTS

 The study included 215 DIEP flaps (45 unilateral and 85 bilateral). The average age was 49.8 years old, and the average body mass index (BMI) was 31.4. Group I (early expectations) included 56 patients (24 unilateral DIEPs, 32 bilateral). Group II (standard expectations) had 74 patients (21 unilateral, 53 bilateral). LOS for unilateral DIEP was 2.9 days for Group I compared with 3.7 days for Group II (p = 0.004). Group I bilateral DIEP patients had LOS of 3.5 days compared with 3.9 days for Group II (p = 0.02). Immediate timing of DIEP (Group I 42.9 vs. Group II 52.7%) and BMI (Group I 32.1 vs. Group II 30.8) were similar (p = 0.25).

CONCLUSION

 Our study found significantly shorter hospital stay after DIEP flap for patients who expected an earlier discharge date despite similar patient characteristics and uniform ERAS protocol. Patient expectations should be considered during patient counseling and as a confounding variable when analyzing ERAS protocols.