Imaging May Identify Potential Delayed Neurological Sequelae After Carbon Monoxide Poisoning

Acute brain lesions observed on diffusion-weighted imaging during the acute phase of carbon monoxide poisoning may help identify patients at risk of developing delayed neurological sequelae, according to a study published in JAMA Neurology. 

Researchers from Korea performed an observational study to determine if acute brain lesions on diffusion-weighted imaging were related to subsequent development of delayed neurological sequelae after acute carbon monoxide poisoning.

Seven hundred adult patients with acute carbon monoxide poisoning were identified for the study; 433 patients (61.9 percent) who underwent diffusion-weighted imaging at an emergency department were included. Patients who developed cardiac arrest before diffusion-weighted imaging (n = 3), had persistent neurological symptoms at discharge (n = 8), committed suicide soon after discharge (n = 1), and were lost to follow-up (n = 34) were excluded, leaving 387 patients (143 women), with a median age of 42 years.

The main outcomes and measures were delayed neurological sequelae defined as any neurological symptoms or signs that newly developed within six weeks of discharge.

The results showed diffusion-weighted imaging revealed acute brain lesions in 104 the 387 patients (26.9 percent):

• 77 patients (19.9 percent) had globus pallidus lesions
• 13 (3.4 percent) had diffuse lesions
• 57 (14.7 percent) had focal lesions (37 patients [9.6 percent] had >1 pattern concurrently)

Lesions were supratentorial and infratentorial in 101 and 23 patients, respectively, the researchers noted. A total of 101 patients (26.1 percent) had delayed neurological sequelae. Multivariable logistic regression analysis indicated that the presence of acute brain lesions was independently associated with development of delayed neurological sequelae.

The sensitivity and specificity of acute brain lesions to assess the probability of delayed neurological sequelae were 75.2 percent and 90.2 percent, respectively. In addition, the positive and negative predictive values were 73.1 percent and 91.2 percent, respectively.

The researchers concluded that the presence of acute brain lesions was significantly associated with the development of delayed neurological sequelae. Diffusion-weighted imaging during the acute phase of carbon monoxide poisoning may therefore help identify patients at risk of developing these debilitating sequelae.