Influence of positioning on plain levobupivacaine spinal anesthesia in cesarean section

Randomised Control Trial Comparing Plain Levobupivacaine and Ropivacaine with Hyperbaric Bupivacaine in Caesarean Deliveries

Objective

The study compared spinal block characteristics of equipotent doses of plain 0.5% levobupivacaine, plain 0.75% ropivacaine and hyperbaric 0.5% bupivacaine for elective caesarean (CS) delivery.

Methods

A total of 100 parturient women undergoing elective CS under spinal anaesthesia were enrolled for the study. The parturients were randomly assigned to receive one of the following in a subarachnoid block: hyperbaric 0.5% bupivacaine 10 mg (group B), plain 0.5% levobupivacaine 10 mg (group L), or plain 0.5% ropivacaine 15 mg (group R).

Results

Motor block duration [groups B, LB, R: 143.78 (30.43) minutes, 139.31 (33.38) minutes, 137.32 (27.39) minutes, respectively; P=0.80], sensory block duration [groups B, LB, R: 122.87 (34.93) minutes, 113.03 (39.24) minutes, 125.58 (24.93) minutes, respectively; p=0.30] and first analgesic request time [groups B, LB, R: 136.87 (28.70) minutes, 133.59 (27.30) minutes, 144.19 (32.09) minutes, respectively; p=0.35] were statistically comparable. The groups were statistically comparable for sensory block onset time [T6 block; groups B, LB, R: 4.62 (2.80) minutes, 4.93 (2.63) minutes, 5.73 (3.00) minutes, respectively; p=0.29] but motor block onset time was statistically prolonged for group R as compared to group B [Bromage 3 block; group B, LB, R: 5.93 (3.41) minutes, 9.00 (4.00) minutes, 10.16 (5.66) minutes, respectively; p=0.001]. No statistically significant differences were seen in sensory and motor block recovery times, haemodynamic parameters or side-effects.

Conclusion

The anaesthesia from a spinal block with 10 mg plain levobupivacaine or 15 mg plain ropivacaine is comparable to the anaesthetic effect of 10 mg hyperbaric bupivacaine in elective caesarean deliveries.

Comparison of 1- and 2-Minute Sitting Positions Versus Immediately Lying Down on Hemodynamic Variables After Spinal Anesthesia with Hyperbaric Bupivacaine in Elective Cesarean Section

BACKGROUND

Hypotension is one of the most common complications of spinal anesthesia in parturients undergoing cesarean section. In this regard, the patient's position may affect the incidence of hypotension.

OBJECTIVES

In this clinical trial, we evaluated the effects of 1- and 2-minute sitting positions versus immediately lying down after spinal anesthesia on hypotension and vasopressor requirements.

METHODS

A total of 72 parturients, scheduled for cesarean section under spinal anesthesia, were randomly divided into 3 groups (24 subjects per group). Groups S1 and S2 remained in a sitting position for 1 and 2 minutes after the induction of spinal anesthesia, respectively, while group T was immediately placed in a lying position. Systolic, diastolic, and mean arterial blood pressure, as well as heart rate, was recorded at 1, 2, 3, and 5 minutes after anesthesia induction, every 5 minutes during the first 30 minutes of surgery, and then every 10 minutes until the end of surgery. P-value less than 0.05 was considered statistically significant.

RESULTS

The overall frequency of hypotension was 50 (69%) cases during surgery; the reported frequency was higher in group T in comparison with group S2 (P = 0.003). The frequency of hypotension before delivery (the first 5 minutes after spinal anesthesia) was 40 (55%) cases, with a higher frequency reported in group T (20, 83%), compared to groups S1 (12, 50%) and S2 (8, 33%) (P = 0.03 and P = 0.001, respectively). The ephedrine requirement in group T (11.73 ± 7.16 mg) was higher than the other two groups (8.69 ± 7.57 and 7.82±7.95 mg in groups S1 and S2, respectively); nevertheless, the difference was not statistically significant (P = 0.19). Moreover, the difference in time to achieve T6 sensory level was only significant between group T (3.25 ± 1.1 minutes) and group S2 (4.73 ± 1.73 minutes) (P = 0.03).

CONCLUSIONS

The present study showed that 1- or 2-minute sitting position after spinal anesthesia with 2.5 cc of hyperbaric bupivacaine in elective cesarean section results in more hemodynamic stability, compared with immediately lying down.

Clinical characteristics of spinal levobupivacaine: hyperbaric compared with isobaric solution

We performed a prospective, double-blinded study in 20 patients undergoing gynecologic surgery with lower abdominal incision, to investigate characteristics of intrathecal hyperbaric levobupivacaine compared with isobaric levobupivacaine. We randomly assigned them to receive 3 mL of either isobaric or hyperbaric 0.42% levobupivacaine intrathecally. We found that hyperbaric levobupivacaine, compared with isobaric levobupivacaine, spread faster to T10 level (2.8 ± 1.1 versus 6.6 ± 4.7 minutes, P = 0.039), reached higher sensory block levels at 5 and 15 minutes after injection (T8 versus L1, P = 0.011, and T4 versus T7, P = 0.027, resp.), and had a higher peak level (T4 versus T8, P = 0.040). Isobaric levobupivacaine caused a wider range of peak levels (L1 to C8) compared with hyperbaric form (T7 to T2). The level of T4 or higher reached 90% in the hyperbaric group compared with 20% in the isobaric group (P = 0.005). Our results suggest that hyperbaric levobupivacaine was more predictable for sensory block level and more effective for surgical procedures with lower abdominal approach. Hyperbaric levobupivacaine seems to be suitable, but the optimal dosage needs further investigation.