Povidone-iodine（PVP-I）is widely used for the disinfection of surgical sites. Although contact dermatitis（CD）due to PVP-I exposure has been studied, few reports have investigated the susceptibility factors in patients, which may be useful in simple screening. The present study compared the characteristics of patients in whom CD developed after PVP-I exposure and those in whom it did not and investigated the contributory factors. Based on data indicating that CD developed most often in the abdominal region of 6,583 patients who underwent surgery in the past two years, 355 patients whose their abdominal region was disinfected using PVP-1 during gastroenterological, gynecological, and transplantation surgery were enrolled. CD due to PVP-1 occurred in 39 patients（11%）. Binary logistic regression analysis was performed with four explanatory variables to determine the effect of CD occurrence. The results showed a correlation with a medical history of red flare due to alcoho（l odds ratio 5.94［95% confidence interval 1.52-23.09］, p < 0.05）and younger age（odds ratio 0.97［95% confidence interval 0.95-0.99］, p < 0.05）. In addition to implementing preventive measures for patients with risk factors detected in a preoperative interview, it is necessary to explain the risk of CD onset fully, obtain the patients’ consent in cases where the use of PVP-1 is unavoidable, and ensure sufficient observation after PVP-1 use.
Background: Noninvasive positive pressure ventilation（NPPV）mask-related pressure injuries occur due to improper fit of the mask. We developed a continuous multi-contact pressure measurement system between the NPPV mask and face to evaluate the mask fitting objectively. This study aimed to evaluate the reliability and validity of the measurement system. Methods: This study involved 20 volunteers who could fit a medium-sized NPPV oronasal mask and 1 rater. For the assessment of intra-rater reliability, and agreement, the contact pressure was measured thrice for 1 min after fitting the NPPV mask and adjusting the leakage volume to approximately 50 L/min. For known-groups validity, we compared the contact pressures between masks with a lower strap tension of > 200 gf and those with a strap tension of approximately 0 gf, the contact pressures were measured once for 10 seconds. This study protocol was approved by an ethics committee. Results: The intraclass correlation coefficient ranged from 0.79 to 0.99, standard error of measurement ranged from 0.3 to 5.6 mmHg, and small detectable change ranged from 0.9 to 15.6 mmHg. For known-groups validity, any contact pressure values of masks with a strap tension of > 200 gf were significantly higher than those with a strap tension of approximately 0 gf at all locations（P < 0.001）. Conclusions: Our measurement system showed high intra-rater reliability and adequate agreement and knowngroups validity to evaluate the NPPV mask fitting in healthy adults with a medium-sized face.