Does prolonged prone position affect intracranial pressure? prospective observational study employing Optic nerve sheath diameter measurements.

BACKGROUND: Our aim in this observational prospective study is to determine whether the prone position has an effect on intracranial pressure, by performing ultrasound-guided ONSD (Optic Nerve Sheath Diameter) measurements in patients with acute respiratory distress syndrome (ARDS) ventilated in the prone position. METHODS: Patients hospitalized in the intensive care unit with a diagnosis of ARDS who were placed in the prone position for 24 h during their treatment were included in the study. Standardized sedation and neuromuscular blockade were applied to all patients in the prone position. Mechanical ventilation settings were standardized. Demographic data and patients' pCO2, pO2, PaO2/FiO2, SpO2, right and left ONSD data, and complications were recorded at certain times over 24 h. RESULTS: The evaluation of 24-hour prone-position data of patients with ARDS showed no significant increase in ONSD. There was no significant difference in pCO2 values either. PaO2/FiO2 and pO2 values demonstrated significant cumulative increases at all times. Post-prone SPO2 values at the 8th hour and later were significantly higher when compared to baseline (p < 0.001). CONCLUSION: As a result of this study, it appears that the prone position does not increase intracranial pressure during the first 24 h and can be safely utilized, given the administration of appropriate sedation, neuromuscular blockade, and mechanical ventilation strategy. ONSD measurements may increase the safety of monitoring in patients ventilated in the prone position.

Pediatric Intracranial Hypertension: A Spotlight on Imaging, the Idiopathic Intracranial Hypertension Treatment Trial, and COVID-19 Associated Cases.

Primary intracranial hypertension (PIH) is characterized by clinical signs of increased intracranial pressure, papilledema, elevated opening pressure, and absence of mass lesion, hydrocephalus, or meningeal enhancement on neuroimaging. Visual changes are a common presenting feature and if untreated there is risk of irreversible vision loss. There have been recent proposed changes to the criteria for PIH along with studies looking at the differences in imaging characteristics between adult and pediatric PIH. The presence of transverse sinus stenosis alone was highly sensitive and specific for pediatric PIH. The Idiopathic Intracranial Hypertension Treatment Trial was an adult, multicenter study that examined the use of acetazolamide and weight loss on the course of PIH. The study confirmed many previously held beliefs including the most common presenting symptom in PIH is headache. Most patients present with bilateral papilledema with 58.2% of patients having symmetric Frisen scale grading and within one grade in 92.8%. Although diplopia is a common reported symptom, very few have evidence of cranial nerve palsy. Male gender, high-grade papilledema, and decreased visual acuity at presentation are risk factors for treatment failure. Acetazolamide use is associated with mild metabolic acidosis. During acetazolamide treatment, monitoring for hypokalemia or aplastic anemia is not recommended. Monitoring transaminases in the titration phase of treatment should be considered due to a case of transaminitis and pancreatitis with elevated lipase. Newer case reports have also seen associations of secondary intracranial hypertension with concurrent COVID-19 infection and MIS-C.

Intracranial hypertension and visual loss following COVID-19: A case report.

A 40-year-old woman presented with headache, bilateral optic disc edema, and visual loss. She had been diagnosed with COVID-19 (coronavirus disease 2019) 15 days ago. Her cerebrospinal fluid opening pressure was 410 mmH2O, and cranial imaging was normal. She had obesity as a risk factor but had not experienced any ophthalmic complaints before. COVID-19 could be a causative or precipitating factor for intracranial hypertension especially in high-risk groups even in the late phases of the disease and has not been discussed in the literature as such. This should be studied further and kept in mind to prevent permanent loss of vision.