Analysis of incidence and risk factors for intra-abdominal hypertension in critically Ill neurosurgical patients: a prospective-observational study

Intra-abdominal hypertension (IAH) is associated with high morbidity and mortality in critically ill patients. However, its characteristics in critically ill neurosurgical cohort remain poorly understood. This study aimed to investigate the prevalence, risk factors, severity and outcomes of IAH in this specific population. This prospective observational study was conducted in a Neurosurgical Intensive Care Unit (NICU) between Apr 2022 to Apr 2024. All eligible critically ill neurosurgical patients had their intra-abdominal pressure (IAP) measured three times daily via a urinary catheter with 25 mL of saline; the mean daily value was recorded. IAH was defined as IAP ≥ 12mmHg. Demographic data, clinical parameters, and potential risk factors for IAH were analyzed. A Total of 283 patients were enrolled. Among them, 53 (18.73%) developed IAH during their NICU stay, and two (3.78% of IAH patients) progressed to abdominal compartment syndrome (ACS). The 180-day all-cause mortality was significantly higher in patients with IAH than those without IAH (33.96% vs. 12.17%, P < 0.001). Multivariate logistic regression analysis revealed that Glasgow Coma Scale scores (GCS) (OR, 0.733; 95% CI, 0.567–0.947; P = 0.018), Sequential Organ Failure Assessment scores(SOFAs) (OR, 1.830; 95% CI, 1.280–2.616; P = 0.001), positive fluid balance (PFB) (OR, 3.855; 95% CI, 1.485–10.004; P = 0.006), tracheotomy (OR, 3.283; 95% CI, 1.241–8.681; P = 0.017), platelet count (OR, 1.006; 95% CI, 1.001–1.010; P = 0.010) and invasive Mechanical Ventilation (IMV) (OR, 5.915; 95% CI, 1.481–23.624; P = 0.012) were significant associations with IAH in critically ill neurosurgical patients. IAH occurred in 18.73% of critically ill neurosurgical patients and was an important associated factor for 180-day mortality. Associated factors independently associated with IAH in this cohort included lower GCS, higher SOFAs, IMV, PFB, tracheotomy, and platelet count. Moreover, IAH was identified as a associated factor for elevated intracranial pressure in these patients.