Comparison of Transcutaneous Electrical Nerve Stimulation and Paravertebral Block for Postthoracotomy Pain Relief

Inadequate relief of postthoracotomy pain is a major reason of increased occurrence of postoperative complications. We aimed to investigate and compare the effects of transcutaneous electrical nerve stimulation (TENS) and paravertebral block (PVB) to relieve pain after thoracotomy procedures.

We studied 40 patients who underwent thoracotomy. Patients were randomly allocated to receive either PVB (group P, n = 20) or TENS (group T, n = 20) for postoperative pain. The electrodes of TENS were placed 2 cm under and 2 cm over the thoracotomy cut on both posterior and anterior sides. The surgeon inserted paravertebral catheters using direct vision at the end of the surgery. A patient-controlled analgesia (PCA) device was connected to all patients. Visual analog scales, patient demand, and consumption of tramadol were evaluated postoperatively.

Mean visual analog scale (VAS) values were significantly lower in group P for all time points. The patients in group P needed lower amounts of opioid (tramadol) and the difference was statistically significant (258.4 ± 13.52 mg vs. 314.4 ± 8.65 mg, p = 0.005). In addition, the number of demand attempts recorded from the PCA device was significantly lower in group P (14.95 ± 13.64 vs. 26.7 ± 17.34, respectively and p < 0.001).

TENS has beneficial effects for pain relief after thoracotomy, without any side effects; however, it cannot provide sufficient pain relief when compared with PVB.