2025 Poster Presentations
P274: PREVALENCE OF PNEUMOCEPHALUS IN PATIENTS WITH IDIOPATHIC CEREBROSPINAL FLUID RHINORRHEA WHO UTILIZE CONTINUOUS POSITIVE AIRWAY PRESSURE FOR OBSTRUCTIVE SLEEP APNEA
Viraj N Shah, MD1; Sofia E Olsson, BS2; Matthew Ryan, MD1; Bradley Marple, MD1; Sei Y Chung, MD1; 1University of Texas Southwestern; 2TCU Burnett school of medicine
Introduction: Obstructive sleep apnea (OSA) is defined as recurrent airway obstruction during sleep, resulting in an apnea-hypopnea index (AHI) score of 5 or greater.OSA is accompanied by symptoms such as snoring and daytime sleepiness, but has been associated with more severe cardiovascular, cerebrovascular, and metabolic morbidity when left untreated. The prevalence of OSA is disproportionately high in patients diagnosed with spontaneous cerebrospinal fluid (CSF) leak, which may be repaired via skull base surgery. However, rhinologic surgeons have been shown to wait a mean of 10.1 days after skull base surgery before resuming continuous positive airway pressure (CPAP) treatment. This is likely due to the perceived risk of pneumocephalus as a result of positive air pressure within the sinonasal system. To date, literature detailing pneumocephalus in the setting of CPAP use following skull base surgery is limited to case reports. The present study analyzes the prevalence of pneumocephalus in patients using CPAP and diagnosed with spontaneous CSF leak.
Methods: This observational case series involved a single-institution chart review of 26 patients who had references to both CPAP and CSF rhinorrhea in their medical history. Information on patient age, sex, race or ethnicity, body mass index (BMI), location of CSF leak, etiology of CSF leak, history of OSA, AHI score, CPAP use, related surgical treatment, and both preoperative and postoperative computed tomography (CT) findings were recorded.
Results: A total of 9 patients with OSA on CPAP and CSF rhinorrhea were included. The average age was 56 years. Nearly half of the sample 44% (n = 4) was of female sex and 44% (n = 4) identified with Black or African American race. The average BMI of patients was 41.8 kg/m^2, and 78% (n = 7) reported CPAP use. AHI was reported in 6 patients with an average score of 24.8. Of the patients, 78% (n = 7) had CSF leaks located at the ethmoid skull base with 22% (n = 2) at the sphenoid skull base. All patients had a diagnosis of idiopathic intracranial hypertension. Preoperative CT imaging revealed a skull base defect associated with CSF rhinorrhea in all patients, yet no patients exhibited pneumocephalus despite daily, compliant CPAP use.
Conclusions: The results of this study suggest that positive airway pressure does not increase risk of pneumocephalus in patients with a compromised anterior skull base. Overall, this may support early resumption of CPAP in postoperative skull base patients who have OSA and are CPAP dependent. These results align with previous studies suggesting that resuming CPAP therapy shortly following transsphenoidal surgery may be less dangerous than previously thought. Being able to resume CPAP postoperatively without delay may help prevent postoperative pulmonary complications. Further multi-institutional studies with larger sample sizes are needed and will help establish definitive guidelines on the use and timing of positive airway pressure in postoperative skull base patients.