Volume-targeted therapy of increased intracranial pressure: the Lund concept unifies surgical and non-surgical treatments

• Published in: Acta anaesthesiologica Scandinavica Vol. 46; no. 8; pp. 929 - 941
• Main Authors: Grände, P.-O., Asgeirsson, B., Nordström, C.-H.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Munksgaard International Publishers 01.09.2002; Blackwell
• Subjects: Anestesi och intensivvård; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Anesthesiology and Intensive Care; Animals; Biological and medical sciences; Blood Volume; Blood-Brain Barrier; Brain - metabolism; brain edema; brain trauma; Capillary Permeability; Cerebrovascular Circulation; Clinical Medicine; colloid osmotic; colloid osmotic pressure; Emergency and intensive care: comas and nervous system diseases; Energy Metabolism; formula; Humans; hydrostatic capillary pressure; Hydrostatic Pressure; Intensive care medicine; Intracranial Hypertension - physiopathology; Intracranial Hypertension - therapy; Klinisk medicin; Medical and Health Sciences; Medical sciences; Medicin och hälsovetenskap; microdialysis; Osmotic Pressure; pressure; Starling; Starling formula; Water-Electrolyte Balance; Human; Nervous system diseases; Intensive care; Pathophysiology; Craniocerebral; Intracranial hypertension; Diseases of the osteoarticular system; Review; Intracranial pressure; Blood brain barrier; Pressure; Trauma; Cerebral disorder; Blood flow; Treatment; Blood volume; Perfusion; Volume; Hydrostatic pressure; Central nervous system disease; Skull disease; Hemodynamics; Cerebral edema; Osmotic pressure
• ISSN: 0001-5172; 1399-6576
• DOI: 10.1034/j.1399-6576.2002.460802.x

Opinions differ widely on the various treatment protocols for sustained increase in intracranial pressure (ICP). This review focuses on the physiological volume regulation of the intracranial compartments. Based on these mechanisms we describe a protocol called ‘volume‐targeted’ (‘Lund concept’) for treatment of increased ICP. The driving force for transcapillary fluid exchange is determined by the balance between effective transcapillary hydrostatic and osmotic pressures. Fluid exchange across the intact blood–brain barrier (BBB) is counteracted by the low permeability to crystalloids (mainly Na+ and Cl–) combined with the high osmotic pressure (5500 mmHg) on both sides of the BBB. This contrasts to most other capillary regions where the osmotic pressure is mainly derived from the plasma proteins (approximately 25 mmHg). Accordingly, the level of the cerebral perfusion pressure (CPP) is of less importance under physiological conditions. In addition cerebral intracapillary hydrostatic pressure (and cerebral blood flow) is physiologically tightly autoregulated, and variations in systemic blood pressure are generally not transmitted to these capillaries. If the BBB is disrupted, transcapillary water transport will be determined by the differences in hydrostatic and colloid osmotic pressure between the intra‐ and extracapillary compartments. Under these pathological conditions, pressure autoregulation of cerebral blood flow is likely to be impaired and intracapillary hydrostatic pressure will depend on variations in systemic blood pressure. The volume‐targeted ‘Lund concept’ can be summarized under four headings: (1) Reduction of stress response and cerebral energy metabolism; (2) reduction of capillary hydrostatic pressure; (3) maintenance of colloid osmotic pressure and control of fluid balance; and (4) reduction of cerebral blood volume. The efficacy of the protocol has been evaluated in experimental and clinical studies regarding the physiological and biochemical (utilizing intracerebral microdialysis) effects, and the clinical experiences have been favorable.