[Effects of lumbar spinal nerve analgesia on the cardiovascular system]

The frequency of cardiovascular adverse effects of lumbar paravertebral nerve root infiltration was investigated.

117 patients with sciatic pain were included prospectively. 60 % of these suffered from known cardiovascular diseases. In 50 patients, cardiac rhythm was investigated by Holter monitoring. In 100 patients blood pressure, heart rate, respiratory rate and oxygen saturation were registered continuously from 5 minutes before to 15 minutes after the administration of a paravertebral nerve root infiltration by means of a non-invasive monitoring system.

A minor rise in systolic and diastolic blood pressure, heart rate and respiratory rate as well as a normalization of these parameters after the nerve root infiltration, were found. These findings were similar for patients with and without pre-existing cardiovascular diseases. No relevant cardiac arrhythmias could be determined. 5 of the 117 patients suffered from presyncope after the nerve root infiltration. These individuals were significantly (p = 0.002) younger than those without presyncope (32.4 +/- 9.3 vs. 55.8 +/- 14.6 years). Presyncope was more frequent during the first treatment with lumbar paravertebral nerve root infiltration in comparison to repeated application of this therapy [4/27 (14.8 %) vs. 1/90 (1.1 %), p = 0.003]. 80 % of the patients who had experienced a presyncope reported a history of similar events.

According to our findings, cardiovascular monitoring for lumbar paravertebral nerve root infiltrations in the treatment of sciatica does not appear to be required. Patients with a presyncope seem to be characterized by age, first treatment and a history of (pre-)syncopes. In these cases, intravenous fluid substitution might be of help in counteracting vasovagal circulatory reactions.