Near-Infrared Spectroscopy Usefulness in Validation of Hyperventilation Test.

Background: The hyperventilation test is used in clinical practice for diagnosis and therapeutic purposes; however, in the absence of a standardized protocol, the procedure varies significantly, predisposing tested subjects to risks such as cerebral hypoxia and ischemia. Near-infrared spectroscopy (NIRS), a noninvasive technique performed for cerebral oximetry monitoring, was used in the present study to identify the minimum decrease in the end-tidal CO2 (ETCO2) during hyperventilation necessary to induce changes on NIRS. Materials and Methods: We recruited 46 volunteers with no preexisting medical conditions. Each subject was asked to breathe at a baseline rate (8−14 breaths/min) for 2 min and then to hyperventilate at a double respiratory rate for the next 4 min. The parameters recorded during the procedure were the regional cerebral oxyhemoglobin and deoxyhemoglobin concentrations via NIRS, ETCO2, and the respiratory rate. Results: During hyperventilation, ETCO2 values dropped (31.4 ± 12.2%) vs. baseline in all subjects. Changes in cerebral oximetry were observed only in those subjects (n = 30) who registered a decrease (%) in ETCO2 of 37.58 ± 10.34%, but not in the subjects (n = 16) for which the decrease in ETCO2 was 20.31 ± 5.6%. According to AUC-ROC analysis, a cutoff value of ETCO2 decrease >26% was found to predict changes in oximetry (AUC-ROC = 0.93, p < 0.0001). Seven subjects reported symptoms, such as dizziness, vertigo, and numbness, throughout the procedure. Conclusions: The rise in the respiratory rate alone cannot effectively predict the occurrence of a cerebral vasoconstrictor response induced by hyperventilation, and synchronous ETCO2 and cerebral oximetry monitoring could be used to validate this clinical test. NIRS seems to be a useful tool in predicting vasoconstriction following hyperventilation.

Assessment of Sarcopenia Related Quality of Life Using SarQoL® Questionnaire in Patients With Liver Cirrhosis.

Introduction: Sarcopenia, malnutrition, physical deconditioning, and frailty contribute to a significantly altered quality of life (QoL) in patients with cirrhosis and sarcopenia. Aim: To investigate the sarcopenia-linked alterations of QoL by SarQoL® questionnaire in patients with end-stage liver disease. Methods: Consecutive patients with liver cirrhosis, admitted to our department between May and August 2021, completed the SarQoL® questionnaire by themselves. They were evaluated for sarcopenia according to the 2019 European Working Group on Sarcopenia in Older People (EWGSOP) definition [hand grip cut-offs and skeletal muscle index (SMI) calculation at CT scan]. Results: A total of 71 patients with liver cirrhosis were included in the study, with a median age of 54 years. Sarcopenia was present in 31.2% of patients with Child-Pugh class A, in 58.3% with class B, and in 93.5% with class C. The SarQoL® score was statistically significant and lower in Child-Pugh class C vs. class B and class A (70.2 vs. 66.5 vs. 52.5 points, p = 0.0002). The SarQoL® score was evaluated according to different complications of cirrhosis, with statistically significant lower scores in patients with sarcopenia (p < 0.0001), in patients with ascites requiring paracentesis (p = 0.0006), and in patients with hepatic encephalopathy (p < 0.0001). A cut-off level of 75.9 points for SarQoL® score can accurately detect sarcopenia in patients with end-stage liver disease [area under the receiver operating characteristic (AUROC) curve of.823, SE of 92.1%, SP of 45.5%, positive predictive value (PPV) and negative predictive value (NPV) of 66 and 83.3%, respectively, correctly classified 73.2% of cirrhotic patients with sarcopenia]. Conclusions: The use of SarQoL® questionnaire in cirrhotic patients can, at the same time, evaluate the quality of life and identify subjects with sarcopenia and altered QoL.