JOURNAL OF THE
ROYAL MEDICAL SERVICES

Official Publication for the Jordanian Royal Medical Services


Performance Differences Among Variations Of Systolic, Diastolic, And Mean Arterial Pressures In Prognosticating Mortality In Critically Ill Patients Who Are Taking Norepineprine


Hussien Muhammad Shebli; MD*, “Moh’d Nour” Mahmoud Bani Younes; Ph**, Mohammad Younes Lafi; MD*, Muhannad Mohammad Asi; MD***, Mohammed Ali Obeidat; MD***, Qasim “Moh’d Ali” Khamaiseh; MD+



ABSTRACT

 

Objective: Systolic blood pressure, diastolic blood pressure, and the mean arterial blood pressure are useful markers that can predict morbidity and mortality among critically ill patients and may be used to predict the prognosis of patients with septic shock. Our objective was to compare the ability of percentage variations of the systolic, diastolic, and mean arterial pressures (%SBPvar, %MAPvar, and %DBPvar) to predict the primary outcome of overall 28-day intensive care unit mortality, and the secondary outcomes of early mortality (≤14 days), late mortality (>14 days), and intensive care unit length of stay.


Methods: We performed a retrospective analysis of 163 patients admitted to our adult critical care unit between April 2017 and Sep 2018 who met the inclusion criteria of availability of all required data and who survived or discharged before completing at least 1 week of admission. Independent T-test, Mann Whitney U test, and chi square test were used to express all patient variables. A receiver operating char­acteristic curve (ROC) followed by sensitivity analysis was generated to determine the predictive performances, and the optimal cut-off values for three propose prognosticators.


Results: The mean overall age was 58.37±9.96 years112 subjects (68.71%) were male and 51 subjects (31.29%) were female. The overall 28-day, early, and late ICU mortality rate were 39.26% (64 patients), 9.82% (16 patients), and 29.45% (48 patients), respectively. Our studied three prognosticators of %SBPvar, %MAPvar, and %DBPvar were significantly lower in survivors in compared with non survivors (8.96%±0.26%, 16.34%±0.65%, and 22.52%±1.10% versus 11.04%±4.61%, 21.17%±7.54%, and 35.18%±29.37%, respectively). The area under curve of ROC %MAPvar (0.818) was significantly greater than those of %SBPvar (0.769) and %DBPvar (0.265).


Conclusion: In summary, %MAPvar and %SBPvar prognosticators were an effective, no-cost bedside modalities, and discriminative prognosticators with realistic, reliable, and readily available red flag bedside assessment tools which had high sensitivity, performance, and accuracy to predict early, late, and overall 28-day ICU mortality in septic mechanically ventilated critically ill patients who were receiving norepinephrine as a vasopressor.


Key words: Blood pressure variations, Critically ill patients, Mortality, Norepinephrine, Septic shock.

  

JRMS December 2020; 27(3): 10.12816/0057183



Introduction

Systolic blood pressure (SBP), diastolic blood pressure (DBP), and the mean arterial blood pressure (MAP) are useful markers that can predict morbidity and mortality among intensive care unit (ICU)

Admitted patients and may be used to predict the prognosis of patients with septic shock. Sepsis is a complex syndrome caused by the body’s systemic response to an infection with a major cause of high treatment cost, single or multiple organ dysfunctions.[1-4] C-reactive protein (CRP) is also a useful positive acute-phase reactant marker that can predict morbidity and mortality among critically ill patients. [5,6]  However, the results of CRP and other severity indices of sepsis may not be immediately available upon request, potentially delaying effective dynamic risk stratification and goal directed management in these unstable studied cohort. MAP which defined as 1/3 SBP + 2/3 DBP is a readily and affordable attained comprehensive parameter that combines two physiological pressure parameters (SBP and DBP) into a single parameter and previously has been shown to stratify and served as an early warning prognosticator of high risk septic patients from various aetiologies when compared to SBP and DBP.[7-10] Having reliable indicators and markers that would help prognosticate the survival of these patients is invaluable and would subsequently assist in the course of effective treatment.[11,12] Our objective was to compare the ability of %DBP, %SBP, and %MAP variations to predict the primary outcome of overall 28-day ICU mortality, and the secondary outcomes of early mortality (≤14 days), late mortality (>14 days), and ICU length of stay (LOS). Also, our objective was to determine the optimal cut-off point, sensitivity (TPR), specificity (TNR), Youden’s index (YI), positive and nega­tive predictive values (PPV and NPV), and accuracy index (AI), of the three tested prognosticators.

 

 

 

Methods

This was a single-centre observational retrospective study conducted in the department of adult ICU of King Hussein Medical Hospital (KHMH) at Royal Medical Services (RMS) in Jordan. This study was approved by our Institutional Review Board (IRB), and a requirement for consent was waived owing to its retrospective design. This study included a cohort of 913 critically ill patients admitted to our adult ICU via the emergency department (ED) or via other hospital wards with any medical or surgical problems. After excluded all patients who were died or discharged before completed at least 1 week after admission and included all critically ill patients who their anthropometrics, diagnostics, demographics, hemodynamics, nutritional indices, and all required laboratory data were known, 163 critically ill patients were finally included in our study. Flow chart of critically ill patient’s selection and data collection process is fully illustrated in Figure 1.

All patient continuous variables were expressed as mean± standard deviation by using the independent samples T-test while categorical and ordinal variables were expressed as numbers with percentages by using the chi square test or as median (interquartile range) by using the Mann-Whitney U test, respectively. Analysis values were compared for the two tested groups (survivors vs. non-survivors) and the non-survival group was further analysed after being divided into 2 subgroups, early (≤14 days) and late (>14 days) mortality. A receiver operating char­acteristic (ROC) curve followed by sensitivity analysis was used to determine the area under the ROC curves (AUROCs), predictive performances, and the optimal cut-off values for %SBPvar, %MAPvar, and %DBPvar, YI, TPR, TNR, PPV, NPV, and AI were also calculated.  Statistical analyses were performed using IBM SPSS ver. 25 (IBM Corp., Armonk, NY, USA) and P-values ≤0.05 were considered sta­tistically significant.


 


 

 


Result

The mean overall age was 58.37±9.96 years. 112 subjects (68.71%) were male and 51 subjects (31.29%) were female. The overall 28-day, early, and late ICU mortality rate were 39.26% (64 patients), 9.82% (16 patients), and 29.45% (48 patients), respectively. 28-day ICU mortality was significantly higher in medically than surgically admitted patients (85.94% (55 medically patients) versus 14.06% (9 surgically patients), respectively). Baseline pre-ICU admission days and number of co-morbidities >1 were also significantly higher in non-survivors than survivors (7.42±4.57 days versus 2.23±1.06 days and 65.63% (42 subjects) versus 47.47% (47 subjects), respectively). Despite baseline albumin level (ALB1) was significantly higher in non-survivors (2.94±0.39 g/dl) than survivors (2.63±0.20 g/dl), survivors had significantly higher average administered human albumin (H.ALB) doses and nutritional protein density (PD) inputs and significantly lower CRP (18.89±3.16 g/day and 3.72±0.74 g/100 Cal and 28.38±14.38 mg/dl, respectively) than non-survivors (14.06±6.09 g/day and 3.50±0.36 g/100 Cal and 43.09±19.28 mg/dl, respectively) which ultimately resulted in significantly higher average ALB during ICU admission in survivors (2.87±0.12 g/dl) than in non survivors (2.57±0.13 g/dl). The ICU and overall hospital LOS were also significantly lower in survivors non survivors (9.23±1.06 days and 11.46±2.12 days versus 17.30±4.14 days and 24.72±1.98 days, respectively).


Table I: Demographics and anthropometrics comparison of study’s critically ill patients.

Variables

Total

(N=163)

Survivors

(N=99 )

Non-survivors (N=64)

P-Value

Early Mortality

(≤14 days)

(N=16)

Late Mortality (>14 days)

(N=48)

Age (Yrs)

58.37±9.96

58.55±9.948

58.09±10.053

0.92

(NS)

62.31±11.12

56.69±9.38

Gender

Male

112 (68.71%)

67 (67.68%)

45 (70.31%)

0.79

(NS)

11 (68.75%)

34 (70.83%)

Female

51 (31.29%)

32 (32.32%)

19 (29.69%)

5 (31.25%)

14 (29.17%)

Day(s) Pre-ICU admission (day(s))

4.27±3.91

2.23±1.06

7.42±4.57

0.00

(S)

13.31±5.89

5.46±1.10

ICU Stay day(s)

12.40±4.79

9.23±1.06

17.30±4.14

0.00

(S)

10.56±1.97

19.54±1.10

Hospital Stay day(s)

16.67±6.81

11.46±2.12

24.72±1.98

0.00

(S)

23.87±3.93

25.00±0.00

Number of comorbidities

0, 1

74 (45.39%)

52 (52.53%)

22 (34.38%)

0.03

(NS)

3 (18.75%)

19 (39.58%)

2 , 3, 4+

89 (54.60%))

47 (47.47%)

42 (65.63%)

13 (81.25%)

29 (60.42%)

Admission class

Medical

105 (64.42%)