The Regularity And Prognostic Significance Of Ambulatory Blood Pressure In The Critically Ill Patients

Objective: To observe the regularity of 24-hour ambulatory blood pressureand investigate the relationship between the regularity and prognosis in critically ill patients.Method: 76 critically ill patients, whose acute physiologic and chronic healthevaluation II (APACHE II) score are more than 20, were studied after they were hospitalized in ICU of Tianjin medical university general hospital from January 2001 to July 2003. The patients were divided into two groups(survivor an death) based on prognosis, and measured 24-hour ambulatory blood pressure within 48 hours. The average blood pressure and pulse pressure, the diurnal blood pressure rhythm and blood pressure variability of systolic/diastolic during 24-hour, daytime and nighttime were calculated. The prognostic significance of the parameters of the ambulatory blood pressure were evaluated by Logistic regression.Result: The average blood pressure of 24 hour systolic/diastolic and pulsepressure increased in the both. The average blood pressure was higher in death group during 24-hour, daytime and nighttime (P<0.05). There was no difference in dipper and nondipper between two groups(x2 -0.02, P>0.05). 24-hour systolic/diastolic blood pressure variability were higher in death than in survivor (P<0.05), but the nighttime diastolic blood pressure variability was lower. The systolic/diastolic blood pressure variability were similar between two group in daytime. The factors affecting the prognosis defined by Logistic regression include APACHE II score, 24-hour average systolic/diastolic blood pressure,-3-nighttime average diastolic blood pressure, daytime systolic blood pressure variability and nighttime diastolic blood pressure variability.Conclusion: Hypertension was observed in critically ill patients, and thediurnal blood pressure rhythm was disappeared. The blood pressure variability in different time were related to the prognosis. The ambulatory blood pressure monitoring is useful in evaluating the therapy and predicting the prognosis in critically ill patients.