C-sect: What works and what not?

Infiltration of caesarean section (C-sect) incision with single-shot bupivacaine and adrenalin during the procedure helps women in terms of postoperative pain relief, while prophylactic use of tranexamic acid (TXA) after C-sect appears to be of limited benefit, according to studies presented at SMFM 2022.

“[Although] surgical wound infiltration with local anaesthetics is recognized as an effective technique for postoperative pain relief after diverse surgeries, the magnitude of the effect in C-sect is uncertain,” said the researchers.

In the first study, 288 term pregnant women scheduled for C-sect were randomized 1:1 to incisional infiltration with bupivacaine and adrenalin or control without infiltration at a university teaching hospital in Israel. Those in the active intervention group had their incision infiltrated on both sides at the subcutaneous layer with a 30 mL mixture of 0.25% bupivacain and adrenalin (1:200,000) before wound closure. [SMFM 2022, abstract 22]

Within 24 hours after surgery, the primary outcome of postoperative pain intensity was significantly lower in women who received bupivacaine/adrenalin infiltration than those who did not (mean VAS* score, 1.99 vs 2.32 cm; p=0.02).

Moreover, postpartum use of rescue opioid analgesics was significantly less frequent among women who received infiltration than those in the control group (p=0.009).

The infiltration group also reported a greater satisfaction in a survey using a 1-5 scale compared to the control group (p=0.007).

No differences were seen in operation length (p=0.15), rate of scar haematoma (p=0.25), length of hospital stay (p=0.85), and time to first mobility (p>0.99).

“Infiltration of the incision with single-shot bupivacaine and adrenalin during C-sect reduces postoperative pain and improves women satisfaction,” the researchers summed up.

TXA: Benefits in some outcomes, but not others

In another multicentre, double-blind trial, 10,995 women with planned C-sect delivery were randomized to receive either 1 g of TXA intravenously or placebo immediately after umbilical cord clamping. [SMFM 2022, abstract LB03]

The primary composite outcome comprising maternal death or transfusion of packed red blood cells (pRBC) within 7 days postpartum or by hospital discharge occurred in 201 patients who received TXA compared with 233 patients in the placebo group (rate, 3.6 percent vs 4.3 percent; relative risk [RR], 0.85, 95 percent confidence interval [CI], 0.71–1.03; p=0.10).

Nonetheless, TXA appeared to benefit in terms of reducing the need for treatment for bleeding compared with placebo (RR, 0.90; 97.5 percent CI, 0.82–0.99; p=0.02).

In addition, women who received prophylactic TXA also saw a smaller decrease in haemoglobin concentration from pre- to post-operative period compared with the placebo group (by 1.75 vs 1.87 g/dL; p<0.001).

The researchers found no significant differences between the two groups for other secondary outcomes, as were for adverse events including thrombotic complications.

“Prophylactic administration of TXA during C-sect delivery did not reduce the need of pRBC transfusion but modestly decreased the use of treatments for haemorrhage, specifically the use of uterotonics,” said the researchers.

*VAS: Visual analogue scale