Background
Methods
Patients
Diagnostic work-up and follow-up after shunting
Monitoring and analysis of CO, ABP and ICP wave amplitudes
Management Groups | |||
---|---|---|---|
Group A (elevated MWAICP) | Group B (low MWAICP) | Significance | |
Demographic
| |||
Patients (n) | 20 (69%) | 9 (31%) | |
Age (yrs) | 76 (53 - 84) | 78 (66 - 80) | ns |
Gender (F/M) | 12/8 | 3/6 | ns |
BMI | 24.3 (15.1 - 29.4) | 24.0 (20.0 - 31.3) | ns |
Vascular co-morbidity
| |||
Diabetes | 5 (25%) | 1 (11%) | ns |
Hypertension | 3 (15%) | 3 (33%) | ns |
Cardiovascular | 8 (40%) | 3 (33%) | ns |
Cerebrovascular | 5 (25%) | 2 (22%) | ns |
Cardiac arrhythmia | 3 (15%) | 3 (33%) | ns |
Radiology
| |||
Evan's index | 0.37 (0.30 - 0.44) | 0.38 (0.33 - 0.42) | ns |
Symptoms
| |||
Duration of symptoms (yrs) | 2.0 (0.4 - 10) | 2.0 (0.8 - 6.0) | ns |
Preoperative NPH score | 10 (7 - 13) | 10 (9 - 11) | ns |
Treatment
| |||
Conservative (n) | 1 | 6 | |
Shunt (n) | 19 | 3 | |
Outcome
| |||
Shunt Non-responders | 3 (16%) | 3 (100%) | |
Shunt Responders | 16 (84%) | - |
Management groups | |||
---|---|---|---|
Group A (elevated MWAICP) | Group B (low MWAICP) | Significance | |
Duration of recording
| |||
Accepted 6-s time windows | 7,329 (1,022 - 12,388) | 7,416 (3,370 - 9,143) | ns |
Cardiac parameters
| |||
CO (l/min) | 5.6 (3.6 - 9.6) | 5.5 (3.7 - 6.4) | ns |
SV (ml/beat) | 81.1 (48.4 - 134.5) | 82.1 (52.9 - 103.1) | ns |
HR (beats/min) | 68.6 (58.8 - 89.7) | 67.1 (62.3 - 87.9) | ns |
DO2 (ml ∙ min ∙ m2)l) | 1,006 (593 - 2,104) | 923 (759 - 1,097) | ns |
SVR (dyne ∙ s∙ cm5) | 1,448 (508 - 2,157) | 1,426 (997 - 2,144) | ns |
ABP parameters
| |||
Mean ABP (mmHg) | 90.7 (72.5 - 112.3) | 96.2 (78.0 - 108.1) | ns |
Mean ABP wave amplitude (MWAABP; mmHg) | 68.6 (52.0 - 110.0) | 60.9 (42.1 - 77.6) | ns |
ICP parameters
| |||
Mean ICP (mmHg) | 6.4 (2.3 - 11.9) | 4.7 (2.1 - 10.8) | ns |
Mean ICP wave amplitude (MWAICP; mmHg) | 5.6 (4.0 - 10.2) | 3.4 (2.8 - 4.0) | c |
Percentage mean ICP wave amplitude (MWAICP) ≥5 mmHg | 68 (11 - 100) | 2 (1 - 7) | c |
CPP
| |||
Mean CPP (mmHg) | 87.2 (62.7 - 112.1) | 92.9 (75.5 - 107.7) | ns |
Correlation values
| |||
CO/MWAABP | 0.37 (0.02 - 0.80) | 0.55 (0.09 - 0.87) | ns |
CO/MWAICP | -0.06 (-0.24 - 0.21) | 0.07 (-0.12 - 0.39) | a |
MWAABP/MWAICP | 0.05 (-0.29 - 0.32) | 0.09 (-0.15 - 0.35) | ns |
Patient number | Number of 6s recordings | CO/MWAABP | CO/MWAICP | MWAABP/MWAICP | Management group | Outcome Category |
---|---|---|---|---|---|---|
1 | 3,370 | 0.55
c
| -0.11c | 0.09
c
| B | C |
2 | 12,388 | 0.54
c
| -0.12c | -0.22
c
| A | NR |
3 | 4,776 | 0.08
c
| 0.08c | 0.32
c
| A | C |
4 | 10,627 | 0.31
c
| 0.09c | 0.01 | A | R |
5 | 6,562 | 0.66
c
| -0.18c | -0.22
c
| A | R |
6 | 7,627 | 0.52
c
| -0.24c | -0.29
c
| A | R |
7 | 6,081 | 0.25
c
| -0.18c | -0.14
c
| A | R |
8 | 8,501 | 0.87
c
| 0.23c | 0.23
c
| B | NR |
9 | 8,172 | 0.85
c
| 0.37c | 0.35
c
| B | NR |
10 | 1,022 | 0.25
c
| -0.003 | 0.14
c
| A | R |
11 | 10,715 | 0.63
c
| 0.18c | 0.26
c
| A | R |
12 | 4,519 | 0.60
c
| -0.08c | 0.003 | B | C |
13 | 6,089 | 0.80
c
| -0.04a | 0.04
a
| A | R |
14 | 8,518 | 0.12
c
| -0.19c | 0.23
c
| A | NR |
15 | 8,202 | 0.59
c
| -0.03a | 0.05
c
| A | R |
16 | 7,030 | 0.14
c
| -0.05c | 0.21
c
| A | R |
17 | 3,538 | 0.25
c
| -0.12c | -0.15
c
| B | C |
18 | 8,239 | 0.58
c
| -0.07c | -0.07
c
| A | R |
19 | 7,416 | 0.44
c
| 0.005 | 0.18
c
| B | C |
20 | 8,117 | 0.04
c
| -0. 08c | 0.21
c
| A | R |
21 | 5,476 | 0.02 | -0.17c | 0.18
c
| A | R |
22 | 8,991 | 0.09
c
| 0.39c | 0.07
c
| B | C |
23 | 6,441 | 0.42
c
| -0.12c | -0.07
c
| A | R |
24 | 9,478 | 0.15
c
| -0.02 | 0.04
c
| A | R |
25 | 9,143 | 0.29
c
| 0.07c | 0.24
c
| B | NR |
26 | 5,291 | 0.12
c
| -0.13c | -0.03
a
| A | NR |
27 | 6,409 | 0.73
c
| 0.21c | 0.23
c
| A | R |
28 | 6,467 | 0.61
c
| 0.11c | 0.06
c
| B | C |
29 | 8,311 | 0.57
c
| 0.15c | 0.10
c
| A | R |
Median
| 7,416 | 0.44 | -0.04 | 0.07 | ||
Ranges
| 1,022 - 12,388 | 0.02 - 0.87 | -0.24 - 0.39 | -0.29 - 0.35 |
Statistical analysis
Results
Patients
Shunt response versus cardiac and pressure data
The association between CO and ICP wave amplitudes
MWAABP/MWAICP correlation | |||
---|---|---|---|
CO/MWAICP correlation | Significant positive | Significant negative | Significancea |
Significant positive | 9 | 0 | |
Significant negative | 7 | 8 | P = 0.009 |