Relevance of the expression “ obs stabl e ” : a retrospective study

1. Relevance of the expression “obs stable”: a retrospective study Gregory Scott Academic clinical fellowRoshan Vijayan Core surgical traineePandora Male Medical student

2. Obs stable

3. Seriousness Serious and important  BMJ Quite silly and not important  Christmas BMJ Importance

4. Should we seriously worry about what we write?

5. What’s wrong with “obs stable”? • “Stable” might be interpreted as “normal” But A patient with persistent tachycardia has “stable” observations 2. “Obs stable” implies a lack of rigour

6. What do we even mean by “stable”? Current obs within “normal” range? Variation in obs within “normal” limits (L) for a given time period (t)? L t

7. Study • Objective: To ascertain whether use of the term “obs stable” is so liberal as to render it meaningless. • Design: Retrospective study • Setting: Three London hospitals • Methods • Searched notes for current admission of 46 randomly selected inpatients for “obs stable” entries • Reviewed the nursing observations recorded during the 24 hours preceding each entry • Calculated for these 24 hour periods: • Frequency of anyabnormalities • Frequency of persistent abnormalities (occurring in every observation) • Range (max.-min.) of observation values if at least two observations had been recorded

8. Results: “obs stable” occurrences • 1+ “obs stable” entry in 36 (78%) notes • 178 “obs stable” entries total (3.9 per patient) • 1st “obs stable” entry on day 2 (median) • 3.9 nursing observations charted in the 24 hours before each entry (SD 1.4)

9. Results: abnormalities in the 24 hours preceding “obs stable” • 1+ abnormality in 113 (71%) of 159 cases • Tachypnoea (55%), hypotension (21%), tachycardia (13%), desaturation (16%) • 1+ one persistent abnormality in 31 (19%) cases • Abnormality occurred in the observations immediately preceding an entry in 42% • Definitions • Hypotension = SBP <100mmHg, Tachycardia = HR >100/min • Pyrexia = temperature >38C, Tachypnoea = RR≥20/min • Oxygen desaturation = saturations <95%

10. Results: all “stable” observations

11. Results: 24 hourly range of “stable” observations

12. Discussion: findings • Doctors regularly used the expression “obs stable” • “Obs stable” was often associated with a 24 hour period which included abnormal observations • In two fifths of cases, an abnormality occurred in the observations immediately preceding an “obs stable” entry • The range of observations over a 24 hour period that were designated “stable” occasionally exceeded normal values of diurnal variation

13. Discussion: limitations • Small sample • No comparison with non-“stable” entries • Arbitrary definition of abnormalities • Arbitrary choice of 24 hour period • Difficult to define “normal” diurnal variation

14. Discussion: why do we write“obs stable”? • Lack of time given to documentation • Intended to be less committal • Observation chart design • The patient seems well

15. Conclusions • The meaning of “obs stable” is ambiguous and does not always indicate normality. • What could we write instead? • Write the observations in full • Qualify “obs stable” by adding “for the last X hours” or • “Last abnormal observation was X [observation] at Y [time]” • Perhaps obs stable has become ubiquitous precisely because it of its ambiguity.

17. Thank you