Postoperative Interventions

Systemic non-opioid analgesics

Arguments for…

One study compared morphine (20 mg), paracetamol (4 g) or ketorolac (120 mg), administered at the end of the surgery and during 24 h postoperatively (Dastan 2020). Mean (SD) VAS pain scores on coughing were significantly higher in the morphine group throughout the study period (morphine: 3.5 ± 2.5; ketorolac: 1.4 ± 1.4; paracetamol: 2.7 ± 2.6).
- Morphine 0.05–0.1 mg/kg was used as rescue analgesia in the three groups. The number of patients who needed rescue medication was higher in the paracetamol group. However, the mean dose of morphine given as rescue was comparable in the three groups.
- There was a clinically unimportant difference in the volume of blood loss between the groups (ketorolac: 291 ml; paracetamol: 250 ml; morphine: 169 ml).
One study compared paracetamol with ketorolac after VATS (Jahangiri 2016), finding no significant difference in pain scores, morphine consumption, and patient satisfaction.
- Patients received the study drugs at the end of the surgical procedure and postoperatively as a continuous infusion. They did not receive any additional baseline analgesia but had IV morphine as a rescue.
- The volume of blood in thoracic drains was significantly higher in the ketorolac group (309 ml versus 273 ml; p=0.001) but the difference was not clinically relevant. There was no difference in other side effects.

Systemic analgesia should include paracetamol, NSAIDs or COX-2 specific inhibitors administered pre-operatively or intra-operatively and continued postoperatively.
- The benefits of these basic analgesics are well described for other procedures (Ong 2010; Martinez 2017).

Arguments for…

Bai 2019 compared different opioids and modalities of administration: IV morphine PCA without basal infusion; IV hydromorphone PCA with a basal infusion; or IV hydromorphone PCA without basal infusion. Basic analgesia (paracetamol, NSAIDs) was not reported. Surgeons performed an ICNB in all patients. They found no difference in pain scores or patient satisfaction.
Morphine was commonly used as a rescue to treat postoperative pain using PCA, and opioid (commonly morphine) consumption was used as an outcome in most studies.

Arguments against…

No study evaluated anaesthesia with different opioids (remifentanil, sufentanil, fentanyl) or without opioids (opioid-free anaesthesia).

Arguments for…

One study compared transcutaneous electrical acupuncture points stimulation versus placebo TENS using very low amperage (Chen 2020). Basic analgesia was not reported and no additional baseline analgesia was used. They found a reduction in mean VAS pain scores up to 48 h postoperatively (3.2 versus 5.8 at 6 h, 2.9 versus 6.0 at 24 h and 1.7 versus 2.9 at 48 h), with reduced consumption of rescue morphine.

Arguments against…

One study compared TENS plus opioid analgesia versus opioid analgesia alone (Engen 2016). Basic analgesia was not reported. No difference in analgesia or opioid consumption was observed.