Objective: Blood pressure (BP) and heart rate (HR) follow a circadian rhythm. The aim of the study was to assess the BP and HR patterns in shift intensive care unit (ICU) nurses. Design and method: We enrolled 21 nurses working in an 8 hours shift schedule (morning: 07–15, afternoon: 15–23, night: 23–07) at a general ICU. Demographic and clinical data was obtained by completing a short questionnaire. The nurses were invited to measure their BP and HR at the beginning, in the middle and at the end of their shift. Collected information also included shift details (e.g. number of new admitted patients). An ESH certified automatic device was used for the BP and HR measurements. Results: The mean age of the nurses was 40,4 ± 5,0 years with a mean work experience of 14,2 ± 6,0 years (7,3 ± 5,3 years in ICU). In total, there were 560 BP and HR measurements in 246 shifts (97 shifts missing no measurement). The mean systolic BP, diastolic BP and HR were 112,1 ± 12,7 mmHg, 73,4 ± 8,8 mmHg and 81,7 ± 10,3 bpm. There was no difference in the mean levels of BP and HR in relation to the type of shift (Table 1a). Moreover no difference could be demonstrated when analysis was focused comparing the mean BP and HR levels in the beginning, in the middle and the end of the shift in each of the three types of shifts (Table 1b). Nevertheless, it was noticed that BP and HR levels were apparently not stable in each shift for every nurse, but could be rising or falling, with maximum variation observed in afternoon shift (Table 1c).Conclusions: The mean systolic and diastolic BP and HR levels of shift ICU nurses appear to be stable between the three types of shifts (morning, afternoon and night) irrespective of the measurement timing (start, middle, end of shift). On the contrary, the variation of BP and HR levels in each separate shift for every nurse is significant and maximized in the afternoon shift. It could be contemplated that BP and HR levels of ICU shift nurses do not follow a circadian pattern.
Read full abstract