The monitoring of vital signs on adult medical wards

Aims

Ward patients have been found to have abnormal vital signs in the hours prior to ICU admission and preceding cardio-pulmonary arrest. This study aimed to assess nursing staffs' knowledge of vital signs, and whether they increase the frequency of observations in response to abnormal values.

Method

The study was performed over a 24-hour period on the medical wards of a London hospital. Observations charts of 233 patients were audited; 634 sets of observations were documented. Accepted normal values for this study were; temperature 36.0–37.4°C; heart rate 50–99 beats/min; systolic BP 100–179 mmHg; respiratory rate 10–19 breaths/min; SaO₂ ≥ 95%. Comparisons were made of the time interval between observations when values were both within and outside the defined range. To assess the knowledge of nursing staff, questionnaires were given to 101 staff; 73 were returned (72% response). The questionnaire had questions about normal values for vital signs and the significance of deviation from these norms.

Results

Comparisons of the intervals between observations are presented in Table 1. Data are given as the mean interval in hours with 95% confidence intervals. A Mann–Whitney U test showed a significant difference in frequency of observations for increased heart rate, increased temperature and decreased SaO₂. No significant difference was detected for abnormal respiratory rate or BP. Performance on the questionnaire was poor; 56% of respondents obtained less than 50%. Areas of concern were oxygen therapy (12%), hypotension (15%), respiratory assessment (23%), recognition of oliguria (31%) and normal respiratory rate (49%).

Table 1

Conclusion

Ward staff failed to increase the frequency of observation for abnormal respiratory rate and BP. Performance in the questionnaire suggests that staff may not understand the clinical significance of these vital signs.