Objective To explore the predictive value of carotid artery corrected flow time (FTc) and heart rate (HR) in elderly patients with hypotension after subarachnoid block (spinal anesthesia).
Methods Forty elderly patients, 21 males and 19 females, aged ≥ 65 years, BMI 18.5-25.0 kg/m2, ASA physical status Ⅱ or Ⅲ, who underwent hip and knee arthroplasty under spinal anesthesia were selected. According to whether hypotension occurred in supine 15 minutes after spinal anesthesia, the patients were divided into two groups: hypotension group (group H) and non-hypotension group (group N). Before spinal anesthesia, the baseline FTc of right common carotid artery was measured under ultrasound, and the baseline values of SBP, DBP, MAP, and HR were recorded. Multivariate logistic regression was used to analyze the influencing factors of hypotension in elderly patients after spinal anesthesia. The receiver operating characteristic (ROC) curves of baseline FTc and HR were drawn and the area under the curve (AUC) was calculated to evaluate the predictive value.
Results Hypotension occurred in 17 patients (43%) after spinal anesthesia. The age and proportion of patients with hypertension and ASA physical status Ⅲ patients in group H were higher than those in group N (P < 0.05). Multivariate logistic regression showed that baseline FTc was an independent factor affecting hypotension, the AUC of baseline FTc was 0.884 (truncation value ≤ 323.4 ms, sensitivity 82.6%, specificity 94.1%), the AUC of baseline HR was 0.850 (truncation value ≥ 80.5 beats/minute, sensitivity 82.4%, specificity 86.1%). There was a low negative correlation between the maximum decrease of SBP and baseline FTc (r = -0.494), and a moderate positive correlation between the maximum decrease of SBP and baseline HR (r = 0.573).
Conclusion Baseline carotid artery FTc and HR can predict hypotension in elderly patients after spinal anesthesia, and baseline FTc has a higher sensitivity and specificity. |
