Immediate postoperative thoracic epidural analgesia following heart surgery: a comparative analysis of patient-controlled continuous thoracic epidural analgesia (PCCTEA) versus intermittent thoracic epidural analgesia (ITEA)

Background

Surgical procedures involving medial sternotomy or anterolateral thoracotomy are still frequently employed in the therapeutic approach to heart diseases. The surgical tissue lesion sets off a series of neurohumoral responses often resulting in undesirable physiological alterations during the immediate postoperative period. Pain plays a relevant role in this context.

Objective

This study aims to compare PCCTEA using fentanyl versus ITEA using morphine, both in the thoracic epidural space in the immediate postoperative period following heart surgery. The primary objective is to identify the most adequate technique for the postoperative ICU setting.

Patient sample and method

This is a prospective, randomized, open-label study involving 18 patients, divided into two groups. Group I (PCCTEA) consisted of nine patients who received fentanyl at a dose of 0.5 μg/kg/h, associated with a patient-controlled bolus of 20 μg up to 20/20 min. Group II (ITEA) consisted of nine patients who received morphine, 1 mg 12/12 h. The observation period began at patient admission to the PO-ICU until removal of thoracic drains, that is, from 12-24 h postoperatively. Monitoring of analgesia (and sedation) was performed with the following methods: Ramsay Scale (sedation) and Visual-Analogue Scale (VAS) (analgesia). Statistical techniques were exploratory data analysis, Mann-Whitney nonparametric test (95%CI) and Kruskal-Wallis test (95% CI).

Results

Statistical analysis of data was performed within 10 h after patient admission to the postoperative ICU. Like the Ramsay Scale, VAS, independently of time, showed a significant difference between the two groups (P < 0.001), with Group II displaying the lowest values. Over time, Group II continued to display lower values, but this difference was not significant (P = 0.134).

Conclusion

Both techniques proved effective for controlling pain and anxiety. ITEA was more efficient, especially when time was not considered, based on the better results in the first 4 h of the postoperative period. A larger patient sample is needed for more adequate evaluation of the results.