Abstract
We analyzed intracranial pressure (ICP) signals during periods of acute intracranial hypertension (ICH) using the Lempel–Ziv (LZ) complexity measure. Our results indicate the LZ complexity of ICP decreases during periods of ICH. The mean LZ complexity before ICH was 0.20 ± 0.04, while the mean LZ complexity during ICH was 0.16 ± 0.03 (p < 0.05). The mean decrease of the LZ complexity values during the ICH episodes was 19.5%. Additionally, we present preliminary evidence suggesting that periods of ICH may be detectable from non-invasive signals coupled with ICP, such as pulse oximetry (SpO2).
Abbreviations
- ApEn :
-
Approximate entropy
- ABP:
-
Arterial blood pressure
- CAR:
-
Cerebral auto-regulation
- HRV:
-
Heart rate variability
- ICH:
-
Intracranial hypertension
- ICP:
-
Intracranial pressure
- LZ :
-
Lempel–Ziv
- TBI:
-
Traumatic brain injury
- SpO2:
-
Pulse oximetry
References
Aboy M, Hornero R, Abásolo D, Álvarez D (2006) Interpretation of the Lempel–Ziv complexity measure in the context of biomedical signal analysis. IEEE Trans Biomed Eng 53:2282–2288
Balestreri M, Czosnyka M, Steiner L, Schmidt E, Smielewski P, Matta B, Pickard J (2004) Intracranial hypertension: what additional information can be derived from ICP waveform after head injury? Acta Neurochir (Wien) 146:131–141
Contant C, Robertson C, Crouch J, Gopinath S, Narayan R, Grossman R (1995) Intracranial pressure waveform indices in transient and refractory intracranial hypertension. J Neurosci Methods 57:15–25
Czosnyka M, Guazzo E, Whitehouse M, Smielewski P, Czosnyka Z, Kirkpatrick P, Piechnik S, Pickard J (1996) Significance of intracranial pressure waveform analysis after head injury. Acta Neurochir 138:531–541
Czosnyka M, Pickard JD (2004) Monitoring and interpretation of intracranial pressure. J Neurol Neurosurg Psychiatry 75:813–821
Goldstein B, McNames J, Ellenby M, Ibsen L, Jacques S, Aboy M, Thong T, Phillips C, Levitte G (2004) ICU monitoring of continuous physiologic signals. Engineering aspects, clinical interpretation, and future directions. In: Shanley TP (ed) Current concepts in pediatric critical care. Des Planes, IL, pp 201–229
Hornero R, Aboy M, Abasolo D, McNames J, Wakeland W, Goldstein B (2006) Complex analysis of intracranial hypertension using approximate entropy. Crit Care Med 34:87–95
Hornero R, Aboy M, Abásolo D, McNames J, Goldstein B (2005) Interpretation of approximate entropy: analysis of intracranial pressure approximate entropy during acute intracranial hypertension. IEEE Trans Biomed Eng 52:1671–1680
Lempel A, Ziv J (1976) On the complexity of finite sequences. IEEE Trans Inf Theory 22:75–81
Luerssen TG (1997) Intracranial pressure: current status in monitoring and management. Semin Pediatric Neurol 4:146–155
Nagarajan R (2002) Quantifying physiological data with Lempel–Ziv complexity-certain issues. IEEE Trans Biomed Eng 49:1371–1373
Portnoy HD, Chopp M, Branch C, Shannon MS (1982) Cerebrospinal fluid pulse waveform as an indicator of cerebral autoregulation. J Neurosurg 56:666–678
Radhakrishnan N, Gangadhar BN (1998) Estimating regularity in epileptic seizure time-series data. A complexity-measure approach. IEEE Eng Med Biol 17:89–94
Wu X, Xu J (1991) Complexity and brain functions. Acta Biophys Cínica 7:103–106
Xu J, Liu ZR, Liu R, Yang QF (1997) Information transformation in human cerebral cortex. Physica D 106:363–374
Zhang XS, Roy RJ, Jensen EW (2001) EEG complexity as a measure of depth of anesthesia for patients. IEEE Trans Biomed Eng 48:1424–1433
Zhang XS, Zhu YS, Thakor NV, Wang ZZ (1999) Detecting ventricular tachycardia and fibrillation by complexity measure. IEEE Trans Biomed Eng 46:548–555
Acknowledgment
This work was supported in part by the “Consejería de Educación de la Junta de Castilla y León” under the Grant VA108A06.
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Hornero, R., Aboy, M. & Abásolo, D. Analysis of intracranial pressure during acute intracranial hypertension using Lempel–Ziv complexity: further evidence. Med Bio Eng Comput 45, 617–620 (2007). https://doi.org/10.1007/s11517-007-0194-x
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DOI: https://doi.org/10.1007/s11517-007-0194-x