{¹Assistant Professor, Department of Anaesthesia} {²Assistant Professor, Department of Paediatrics} Ulhas Patil Medical College and Hospital, Jalgaon Khurd, Jalgaon, Maharashtra, INDIA.

Email: drpoojad11@gmail.com ,  sbtannirwar@gmail.com

RESULTS

In present study 60 pregnant women were enrolled. 30 patients each were allotted to group I (10 mg bupivacaine) and group II (10 mg bupivacaine combined with 2 mg of preservative-free midazolam) Baseline characteristics of pregnant women such as age, weight, height, pulse rate, systolic BP, diastolic BP were comparable in both groups and difference was not statistically significant.

Table 1: Baseline Information and Vitals of Study Groups

In present study early onset time of sensory block, reduced time to achieve complete sensory block and prolonged duration of effective analgesia was noted in group II as compared to group I, and the difference was statistically significant. Complications such as bradycardia, hypotension, nausea and vomiting were noted in present study. Group I had slightly increased number of complications than group II, difference was not statistically significant.

Table 2: Comparison of sensory parameters in two groups.

DISCUSSION

The technique of subarachnoid block is quite simple and single injection results in ideal operating conditions with complete analgesia, profound muscular relaxation, decreased blood loss and minimal ventilatory disturbances. Duration of analgesia could increase through the use of additive compounds (e.g., epinephrine, opioids, neostigmine, midazolam and clonidine) in local anesthetics. Furthermore, these compounds are able to diminish other postoperative complications, such as shivering.^7,8 According to the literature, intrathecal administration of midazolam with local anesthetics is effective in regional and neuraxial anesthesia for postoperative pain control. Midazolam has been shown to have remarkable analgesic effects with limited side effects.⁹ Other investigators have also shown that intrathecal-administered midazolam when added to bupivacaine significantly improved the duration and quality of spinal anesthesia;¹⁰ produced a more effective and longer analgesia in perianal and lower extremity surgeries;¹¹ prolonged the duration of spinal blockade in orthopedic patients and provided postoperative early recovery of motor function in orthopedic and diabetic mellitus patients undergoing foot debridement.¹² Post cesarean delivery patients are at higher risk for thromboembolic events which may also be precipitated by immobility from inadequate pain control or excessive sedation from opioids. Moreover, these women need to ambulate, to be alert and energetic enough to care for, interact with and breastfeed their new born. Early breastfeeding is important immediately after childbirth to promote and improve mother bonding and enhances puerperal changes to regain pre-pregnancy state.¹³ Increasing the duration of analgesia prevents several postoperative complications, such as atelectasis, urinary retention, prolonged hospital stay and increased healthcare costs. Therefore, replacement of conventional analgesic methods with new pain-relieving compounds is of paramount importance.⁸ In study by Karbasfrushan A et al.,¹⁴ pregnant women were consecutively assigned into either bupivacaine (10 mg) plus intrathecal midazolam (2 mg/ml) (BM) (n=62) or bupivacaine plus normal saline (BNS) (n=62). In comparison with the BNS group, mothers in the BM group reported a significant relief in pain (15 min and 120 min) after the surgery. The average time until the first dose of additional analgesic, per mother’s request was 142.18±55.19 min in the BNS vs 178.06±77.33 min in the BM group. Combination of bupivacaine plus intrathecal midazolam was an effective anesthetic technique to provide improvement in pain. The onset of sedation was faster in the BM group compared with the BNS group. The duration of effective analgesia, and the time for regression of sensory analgesia was the same in both groups. Similar findings were noted in present study. Dodawad R et al.,¹⁵ randomly allocated 60 pregnant women in Group BC and Group BM. Both groups received 10 mg (2 mL) of 0.5% hyperbaric bupivacaine. Group BC received 0.4 mL of distilled water, while group BM received 0.4mL(2 mg) of midazolam intrathecally. Postoperative analgesia was significantly longer in the midazolam group compared to the control group (201.5 minutes vs. 357.6 minutes). The mean onset times of the sensory and motor blocks were significantly faster (P < 0.01) in the midazolam group compared to the control group. The mean times to attain the maximum sensory level and motor blocks were also significantly faster in the midazolam group compared to the control group (P < 0.05). The incidence of hypotension was 6.6% in the midazolam group and 36.6% in the control group, which was highly significant. Intrathecal midazolam 2 mg provides significantly longer and effective postoperative analgesia with no side effects.¹⁵Midazolam is from benzodiazepine group of drugs, used as a preoperative sedative or as a sleep medication during operations, and as a sedative drug during delivery, with analgesic effects.¹⁶ Other studies have also found that adding midazolam to bupivacaine significantly increases the duration of postoperative analgesia.¹⁷ Various researchers have evaluated the effectiveness of intrathecal midazolam in postoperative analgesia in normal caesarean patients and noted beneficial effects of addition of midazolam to bupivacaine.^18,19

CONCLUSION

Addition of midazolam in intrathecal bupivacaine for caesarean section prolongs duration of postoperative analgesia with no increase in the incidence of complications. Intrathecal bupivacaine plus midazolam should be used instead of intrathecal bupivacaine alone for elective caesarean section.

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