Figure 2. Heart rate, systolic blood pressure, and the ratio of the SD of the R-R interval to the SD of the R-R interval spreading perpendicularly along the diagonal line (SD^RR:SD sub [partial differential] RR) before, just after, and 1 h after injection of 99.5% alcohol. A heavy solid line shows these values in the patient we describe. The higher solid line indicates these values for other patients who underwent chemical thoracic sympathectomy (n = 13) or mandibular block (n = 10). The systolic blood pressure decreased significantly 1 h after the injection in both the thoracic sympathectomy and mandibular block groups. The SD^RR:SD sub [partial differential] RR ratio showed a significant decrease just after the injection only in the thoracic sympathectomy group. *P < 0.05 versus the value before the alcohol injection. Values are mean +/- SD.