Continuous Epidural Analgesia or Patient-Controlled Regional (Intra-abdominal) Analgesia for Radical Retropubic Prostatectomy. A randomized, double-blind study

Introduction

Postoperative pain after radical retropubic prostatectomy (RRP) can be moderate to severe, but is often self-limiting and of short duration (< 48 h). In a previous study, we demonstrated that thoracic epidural analgesia (TEA) is a better alternative to patient controlled analgesia with morphine (1).

The aim of this prospective, randomized, double-blinded study was to compare intermittent injection of local anesthetics via an intra-abdominal catheter (Patient controlled regional analgesia – PCRA) inserted at the end of the operation with TEA for postoperative pain relief following RRP (Fig 1).

Method

We included 50 patients, physical status ASA 1-2 class who underwent RRP. All patients received a low thoracic epidural (Th10-12) preoperatively and adequate segmental analgesia was confirmed prior to a standardized general anesthesia. At the end of the operation, the surgeon inserted a multi-hole intra-abdominal catheter in the prostatic bed and fixed it onto the abdominal wall.

Patients were randomized into two groups, Group C (TEA) and
Group P (PCRA).
Group C had an infusion of ropivacaine 1 mg/ml, fentanyl 2 µg/ml and adrenaline 2 µg/ml, 10 ml/h during 48 h epidurally and a PCRA on  demand with boluses of 10 ml (maximum once/h) of 0.9% NaCl;
Group P had 0.9% NaCl 10 ml/h epidurally and PCRA bolus with
ropivacaine 0.2% 10 ml on demand (maximum once/h). Morphine 1-2 mg i.v. was given as rescue medication by nurses as needed.

Pain intensity (NRS) was recorded each hour during 0-4 hr and thereafter at 8, 12, 24, 36, 48 hours postoperatively, at rest, deep pain and pain on coughing.

Maximum expiratory pressure (MEP) was used as an objective
measure of pain relief at 24 and 48 h postoperatively. Side effects and complications were recorded in all patients as also time to home readiness and hospital discharge using standardized criteria.

Results

Group C had significantly lower pain intensity at rest (4 and 24 hours) and on coughing (4 -24-48 hours) (Fig 2-3) and lesser rescue morphine requirement compared to Group P (p < 0.01) (Table 1).

MEP was significantly higher in Group C compared to Group P (p < 0.05) (Table 2). No differences were found in time to home-readiness and hospital discharge between the groups. No differences in side effects or complications were revealed between the groups.

 

Numeric rating scale (NRS) for pain at rest and on coughing. Results are shown as median and IQ range. *=P‹0.005

Conclusions

TEA using a combination of ropivacaine-fentanyl-adrenaline was found to result in:

• lower NRS score at rest (4-24 h) and on coughing
  (4-24-48 h) postoperatively
• lesser morphine requirement during 0-48 h postoperatively
• higher MEP scores at 24 h
• similar incidence of side effects

PCRA technique is an alternative when TEA cannot be used. However, TEA remains the “gold standard” in postoperative pain management following RRP.

References

1. Gupta A, Fant F, Axelsson K, Sandblom D, Rykowski J, Johansson J-E, Andersson S-O. Anesthesiology 2006; 105:784-93.