The Determination of Step Frequency in 3-min Incremental Step-in-Place Tests for Predicting Maximal Oxygen Uptake from Heart Rate Response in Taiwanese Adults

The maximal oxygen uptake (VO2max) prediction models established by step tests are often used for evaluating cardiorespiratory fitness (CRF). However, it is unclear which type of stepping frequency sequence is more suitable for the public to assess the CRF. Therefore, the main purpose of this study was to test the effectiveness of two 3-min incremental step-in-place (3MISP) tests (i.e., 3MISP30s and 3MISP60s) with the same total number of steps but different step-frequency sequences in predicting VO2max. In this cross-sectional study, a total of 200 healthy adults in Taiwan completed 3MISP30s and 3MISP60s tests, as well as cardiopulmonary exercise testing. The 3MISP30s and 3MISP60s models were established through multiple stepwise regression analysis by gender, age, percent body fat, and 3MISP-heart rate. The statistical analysis included Pearson’s correlations, the standard errors of estimate, the predicted residual error sum of squares, and the Bland–Altman plot to compare the measured VO2max values and those estimated. The results of the study showed that the exercise intensity of the 3MISP30s test was higher than that of the 3MISP60s test (% heart rate reserve (HRR) during 3MISP30s vs. %HRR during 3MISP60s = 81.00% vs. 76.81%, p < 0.001). Both the 3MISP30s model and the 3MISP60s model explained 64.4% of VO2max, and the standard errors of the estimates were 4.2043 and 4.2090 mL·kg−1·min−1, respectively. The cross-validation results also indicated that the measured VO2max values and those predicted by the 3MISP30s and 3MISP60s models were highly correlated (3MISP30s model: r = 0.804, 3MISP60s model: r = 0.807, both p < 0.001). There was no significant difference between the measured VO2max values and those predicted by the 3MISP30s and 3MISP60s models in the testing group (p > 0.05). The results of the study showed that when the 3MISP60s test was used, the exercise intensity was significantly reduced, but the predictive effectiveness of VO2max did not change. We concluded that the 3MISP60s test was physiologically less stressful than the 3MISP30s test, and it could be a better choice for CRF evaluation

Prophylactic Antibiotics for Deep Inferior Epigastric Perforator Flap Breast Reconstruction: A Comparison between Three Different Duration Approaches

Background:. There is no consensus on the duration of prophylactic antibiotic use for autologous breast reconstruction after mastectomy. We attempted to standardize the use of prophylactic antibiotics after mastectomy using a deep inferior epigastric perforator flap for the breast reconstruction procedure. Methods:. This retrospective case series included 108 patients who underwent immediate breast reconstruction with a deep inferior epigastric perforator flap at the Ditmanson Medical Foundation Chia-Yi Christian Hospital between 2012 and 2019. Patients were divided into three groups based on the duration of prophylactic antibiotic administration (1, 3, and >7 days) for patients with drains. Data were analyzed between January and April 2021. Results:. The prevalence of surgical site infection in the breast was 0.93% (1/108), and in the abdomen it was 0%. The patient groups did not differ by age, body mass index, smoking status, or neoadjuvant chemotherapy. Only one patient experienced surgical site infection in the breast after half-deep necrosis of the inferior epigastric perforator flap. There were no significant differences in surgical site infection based on the duration of prophylactic antibiotic use. The operation time, methods of breast surgery, volume of fluid drainage in the first 3 days of the abdominal and breast drains, and day of removal of the abdominal and breast drains did not affect surgical site infection. Conclusion:. Based on these data, we do not recommend extending prophylactic antibiotics beyond 24 hours in deep inferior epigastric perforator reconstruction