REVIEW
The foundation of care for patients with severe brain injuries is to monitor and control intracranial pressure (ICP), cerebral perfusion pressure (CPP), and mean arterial pressure (MAP), while managing fluctuations that may lead to further brain injuries. Various measures can be implemented in practice for such controls, including raising the head of the bed, hypothermia, pain and sedative medications, mechanical ventilation, neuromuscular blockade, controlled hyperventilation, and fluid therapy. The therapeutic positioning of the head plays a crucial role in this management, as it can have beneficial effects on the cerebral physiology of these patients, allowing for a reduction in ICP without compromising CPP and cardiac output. The aim of this study is, therefore, to conduct a literature review to provide a critical and up-to-date analysis of the effects of head elevation on intracranial pressure and cerebral oxygenation in patients with acute brain injury. The present study involves a systematic and integrative literature review of a qualitative and descriptive nature, based on the “PICo” search and analysis strategy. The guiding question is: “What are the effects of head elevation on cerebral oxygenation and intracranial pressure in patients with acute brain injury?” Among all the obtained results, it is worth highlighting four specific positions that caused changes in intracranial pressure (ICP): (a) supine with head elevation at 45º (decrease from 9.68 ± 5.6 to 7.48 ± 5.8), (b) left lateral with head elevation at 15º (increase from 9.92 ± 6.4 to 11.42 ± 5.1), (c) right lateral with head elevation at 15º (increase from 9.2 ± 6.0 to 12.13 ± 7.72), and (d) knee elevation with head elevation at 45º. Regarding post-traumatic intracranial hypertension, the objective is not only to reduce intracranial pressure but also to maintain sufficient cerebral blood flow. To achieve this, the most appropriate treatments for the situation should be chosen. In the case of critically ill patients with acute brain injury and associated intracranial hypertension, the clinical maneuver employed to reduce intracranial pressure is head elevation. However, this clinical management also induces changes in cerebral perfusion pressure, thereby impacting brain oxygenation.
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1MS, Medical student, Universidade Federal do Ceará – UFC, Fortaleza, CE, Brazil.
2MS, Medical student, Universidade Nove de Julho, São Bernardo do Campo, SP, Brazil.
3MS, Medical student, Faculdade Atenas, Sete Lagoas, MG, Brazil.
4MS, Medical student, Universidade Federal de São Paulo – Unifesp, São Paulo, SP, Brazil.
5MS, Medical student, Universidade Federal de Juiz de Fora – UFJF, Juiz de Fora, MG, Brazil.
6MS, Medical student, Pontifícia Universidade Católica do Paraná – PUCPR, Curitiba, PR, Brazil.
7MD, Neurosurgeon, Centro Universitário UNIFACISA, Campina Grande, PB, Brazil.
Received Nov 12, 2023
Accepted Jan 14, 2024