To the Editor— New systems to monitor hand hygiene (HH) can promote good practice and increase the adherence and frequency of HH.Reference Ellingson, Haas and Aiello ^{1 ,} Reference Hagel, Reischke and Kesselmeier ² Isolation precautions are used to reduce the risk of transmission of pathogens from known or unknown sources and to reduce the risk of direct contact with secretions or bodily fluids of patients with suspected or confirmed transmissible infections or contact with contaminated objects in the patient’s environment.Reference Cheng, Tai and Chan ^{3 , 4} This study evaluated the frequency of HH episodes among multidisciplinary team members in rooms of patients with and without isolation precautions located in 3 step-down units (SDUs).

The study was carried out from February 1, 2016, to July 31, 2016, in a private, tertiary-care hospital with 664 beds in São Paulo, Brazil. The hospital has 3 SDUs: a mixed medical surgical unit, a cardiology unit, and a neurology unit. All rooms have a single bed. The Ethics and Research Committee of the Hospital Israelita Albert Einstein approved the study.

To assess HH frequency, we used an electronic monitoring system (i-HealthSys, São Carlos, São Paulo, Brazil) that employs radiofrequency devices with sensors. One sensor is located in each employee’s identification (ID) badge, another is installed in the alcohol-based hand sanitizer dispenser, and another is installed above the patient’s bed. Identification data from the badge of the HCW who cleaned his or her hands are sent to the fixed sensor above the patient’s bed. Using a light in the sensor above the patient’s bed (green for clean hands and red for unclean hands), the HCW is notified in real time about whether HH has been done when approaching the patient’s bed.

Integrated software with a database enables the generation of detailed reports with information on the presence or absence of HH events (date and time where HH occurred), duration of HCW time at the patient’s bedside, the number of times the HCW cleaned his or her hands, and the manner in which and places through which the HCW passed during a certain date and time interval. If the HCW is not using the ID badge, the system records the HH event but does not identify the ID badge; therefore, the system is still able to register all HH events using the alcohol-based sanitizer.Reference Marra and Edmond ⁵

We analyzed the HH data from rooms of patients who were hospitalized for >48 hours and stratified the findings by isolation status. For isolated patients, we included patients that were on contact, airborne, and droplet precautions. During the study period, we used Charlson comorbidity indexReference Martins ⁶ data, and the Simplified Acute Physiology (SAPS 3) admission score,Reference Moreno, Metnitz and Almeida ⁷ collected upon admission to the SDU.

Isolated and nonisolated patient populations were compared. Categorical variables were described by absolute and relative frequencies, and groups were compared using a χ² or Fisher exact test. Numerical variables are described as medians and interquartile ranges because the data are not normally distributed. We used the Mann-Whitney test to compare numerical measures by groups.

To determine factors associated with the number of HH episodes per patient day, we analyzed simple and multiple linear regression models. The statistical package R, version 3.1.3 (R Foundation for Statistical Computing, Vienna, Austria) was used, and a P<.05 significance level was adopted.

In this 6-month study, 768 patients participated. We excluded 13 patients because of equipment technical failure. Therefore, we analyzed 755 patients: 561 patients with no isolation precautions (74.3%) and 194 (25.7%) patients on isolation precautions. The number of HH episodes with alcohol sanitizer per patient day ranged from 0.45 to 177.6; the median was 63.7 HH episodes per patient day.

Regarding heterogeneity between patient profiles and isolation status, patients in isolation had a shorter length of stay in the SDU (P=.027) but a longer total length of stay in the hospital (P=.001). Patients in isolation also had a higher Charlson comorbidity index (P=.046) and a higher probability of death according to SAPS 3 (P<.001). Isolated patients had more devices (P<.001). The median number of HH episodes per patient day was 70 for patients in isolation rooms and 62 for those without isolation precautions (P=.040).

Table 1 shows the estimated effects of the factors studied on the mean number of HH episodes per patient day by simple and multiple linear regression analyses. The overall mean number of HH episodes observed was 63.3 (standard deviation, 29.8) per patient day. The mean increase in HH was 0.28 per patient day for each additional day of hospitalization (P=.038). Independent predictors of HH were surgical service (P=.001), Charlson comorbidity index (P=.012), and the number of devices (P<.001). In the presence of these 3 factors, isolation status was not significantly associated with the frequency of HH (P=.400).

TABLE 1 Estimated Effects for the Mean Number of Hand Hygiene Episodes per Patient Day (N=755)

NOTE. IQR, interquartile range; LOS, length of stay; SDU, step-down unit; CCI, Charlson comorbidity index; SAPS3, simplified acute physiology score, a standard equation of probability of death.

^a Unless otherwise specified, categorical variables are described by absolute frequency and, in parenthesis, percentage.

^b Effects on mean number of hand hygiene episodes per patient-day estimated by univariate linear model.

^c Effects on mean number of hand hygiene episodes per patient-day estimated by multiple linear model controlling for surgical patient type, number of devices and Charlson comorbidity index.

Our electronic system of monitoring was not able to evaluate the WHO’s “My 5 Moments for Hand Hygiene,”Reference Pittet, Allegranzi and Boyce ⁸ and we did not evaluate the quality of HH. Patients and visitors are advised to use alcohol-based sanitizers for HH to prevent infections; therefore, employees, patients, and visitors use the dispensers placed in rooms. We do not know the proportion of use attributable to visitors.

In conclusion, our study did not show differences in HH frequency in isolated versus nonisolated patients’ rooms. We demonstrated higher HH frequency for surgical patients, for patients with multiple devices in situ, and for those with a high Charlson comorbidity index.