Effect of Tracheal Suctioning on Optic Nerve Sheath Diameter in Tracheostomised Head Injury Patients in ICU

Background: Elevated intracranial pressure (ICP) is a critical determinant of outcome in traumatic brain injury (TBI). Although invasive monitoring is considered the benchmark, it is not always feasible in intensive care settings due to potential complications and limited access. Ultrasonographic quantification of the optic nerve sheath diameter (ONSD) has emerged as a promising non-invasive surrogate for ICP. This study evaluates the real-time impact of endotracheal suctioning on ONSD in tracheostomised TBI patients.Material and Methods: This research was conducted in an ICU of a tertiary care. Fifty adult, tracheostomised, mechanically ventilated TBI patients were enrolled. ONSD was quantified utilizing a 7.5-10MHz linear probe before suctioning and at 30–60 seconds (average) post-suctionings. A standardized suctioning protocol was followed, and all measurements were performed by a single intensivist. A prospective observational study was conducted in ICU patients with severe head injury. Optic nerve sheath diameter (ONSD) was measured before and after tracheal suctioning.Results: Average baseline ONSD was 5.41±0.29mm, which significantly increased to 5.77±0.29mm at 30–60 seconds post-suctioning (p<0.001), indicating a transient rise in ICP. Mean arterial pressure (MAP) did not change significantly (p= 0.146), suggesting that the ONSD variation was not driven by systemic hemodynamics.Conclusion: Tracheal suctioning induces a transient but statistically significant increase in ONSD, reflecting a short-lived rise in ICP. These findings highlight the utility of ONSD as a dynamic, bedside ICP monitoring tool and underscores the need for cautious suctioning practices in neurocritical care settings.