In-hospital mortality and SpO2 incritical care patients with cerebral injury: data from the MIMIC‑IV Database

Abstract

Background Evidence regarding the relationship between in-hospital mortality and SpO2 was low oxygen saturations are often thought to be harmful, new research in patients with brain damage has found that high oxygen saturation actually enhances mortality. However, there is currently no clear study to point out the appropriate range for oxygen saturation in patients with craniocerebral diseases. Methods By screening all patients in the MIMIC IV database, 3823 patients with craniocerebral diseases (according to ICD-9 codes and ICD-10) were selected, and non-linear regression was used to analyze the relationship between in-hospital mortality and oxygen saturation. Covariates for all patients included age, weight, diagnosis, duration of ICU stay, duration of oxygen therapy, etc. Results In-hospital mortality in patients with TBI and SAH was kept to a minimum when oxygen saturation was in the 94–96 range. And in all patients, the relationship between oxygen saturation and in-hospital mortality was U-shaped. Subgroup analysis of the relationship between oxygen saturation and mortality in patients with metabolic encephalopathy and other encephalopathy also draws similar conclusions In-hospital mortality and oxygen saturation were all U-shaped in patients with subarachnoid hemorrhage, metabolic and toxic encephalopathy, cerebral infarction, and other encephalopathy, but the nonlinear regression was statistically significant only in patients with cerebral infarction (p for nonlinearity = 0.002). Conclusion Focusing too much on the lower limit of oxygen saturation and ignoring too high oxygen saturation can also lead to increase in-hospital mortality. For patients with TBI and SAH, maintaining oxygen saturation at 94–96% will minimize the in-hospital mortality of patients.

Association between SpO2 and the risk of death in elderly T2DM patients with cerebral infarction: a retrospective cohort study

“…Upon covariate adjustments, individuals with low SpO 2 exhibited a 0.4-fold higher risk of death compared to those with normal levels. This was basically consistent with previous similar research results ( 13 ). In delineating the intricate relationship between low SpO 2 levels and heightened mortality risk in our study cohort, the underlying mechanisms, while not fully elucidated, prompted compelling considerations.…”

“…Furthermore, the risk of death in patients with notably high SpO 2 levels was 1.06 times higher than in those maintaining normal SpO 2 levels. These results harmonized with earlier research ( 13 ). However, the intricate relationship between high SpO 2 and heightened mortality in elderly T2DM patients with cerebral infarction remained enigmatic, but several plausible mechanisms have been proposed.…”

“…Contrary to conventional wisdom associating higher oxygen saturation with improved patients' outcomes, a noteworthy paradox emerged from recent studies is that patients with SpO 2 levels in the 97–100% range exhibited a significantly lower survival rate than those in the 94–98% range ( 11 ). Robust evidence showed that deviating oxygen saturation from the norm contributed to adverse consequences, including heightened risks of decompensated heart failure ( 12 , 13 ). Addressing the discomfort of adult patients aligned with the British Thoracic Society's recommendation, advocating for oxygen administration to achieve a targeted saturation range of 94–98% ( 14 ).…”

“…Furthermore, low SpO 2 levels elevated the mortality risk in conditions such as cerebral embolism, metabolic encephalopathy, and subarachnoid hemorrhage. The optimal SpO 2 range for these neurological conditions exhibited broad consistency, albeit with subtle variations ( 13 ).…”

Oxygen saturation profile in traumatic brain injury animal model after propofol administration

“…Another study reported that oxygen saturation is inversely related to the risk of death, where an increase in oxygen saturation reduces the risk of death [ 27 ]. One percent (1%) increase in oxygen saturation has resulted in an 8% decrease in the risk of death [ 28 ].…”