Dose-to-block Level Relation in Single Shot Spinal Anesthesia for Cesarean Section. (SpinDoBlock)

Centre of Postgraduate Medical Education

Status: Active, not recruiting

Conditions: Spinal Anesthesia Evaluation; Cesarean Delivery

Treatments: Other: data collection; Other: Spinal block level analysis

Study type: Observational

Funder types: Other

Identifiers

NCT06729567

97/2024

Details and patient eligibility

About

The study is designed to support or deny relation between the dose of hyperbaric bupivacaine given intrathecally and extent of spinal block level. There is ongoing debate whether anesthetists should adjust the dose in the range of conventional doses in order to achieve appropriate coverage of anesthesia which would be suitable for cesarean section.

Two strategies are predominantly used: low dose strategy, which is focused on safety, and conventional dose approach, which is more effective in terms of success of anesthesia, with markedly higher rate of spinal block - related complications. It is hypothesized that there may be no relation between block level and the dose if conventional doses are used. For that purpose anesthetic charts of cesarean sections will be reviewed to gather information on the doses of anesthetic used and the level of spinal block they produced.

Full description

Single - shot spinal block for cesarean delivery is a gold standard in obstetric anesthesia. Both level and density of the block may have direct impact on the quality of surgery, patient's comfort and the course of postoperative recovery. Ideal dose of local anaesthetic for single - shot spinal anesthesia is still to be decided, with ongoing debate on using either "low" or "conventional" doses as routine approach. Use of conventional doses of local anesthetic (doses nearing dose effective in 95 percent of patients,ED95) have proven to be superior to low dose regimens in terms of effectiveness and therefore this strategy is widely used, despite the higher risk of spinal block - related complications.

Amount of local anesthestic used is regarded to be a factor of significant influence on its intrathecal spread and the final level of block following single - shot spinal anesthesia. It was investigated in both general and obstetric populations, although most of the studies with results in favor of this relation were designed to assess the other factors, and the extend of sensory block was not set as their primary outcome.

It was previously reported that adjusting the conventional dose of hyperbaric bupivacaine to parturient's height does not change the risk of block failure and rate of complications when compared to fixed - dose regimen. Whether the change in bupivacaine dose within the range of conventional doses results in significant change in sensory block level is not clear.

This retrospective analysis was designed to assess the above relation

Enrollment: 362 patients

Sex: Female

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Cesarean delivery at term under spinal anesthesia
• American Society of Anesthesiologists (ASA) physical status <3
• BMI<40

Exclusion criteria

• Spinal anesthesia with less than 9mg of hyperbaric bupivacaine
• Local anesthetic other than hyperbaric bupivacaine used
• Failed spinal anesthesia
• Poor quality of the anesthetic record - data required for analysis not available

Trial design

362 participants in 1 patient group

Parturients given spinal block with conventional dose of bupivacaine for cesarean delivery

Description:

Using electronic hospital database we will identify cases of cesarean section. Initially, all cases of cesarian delivery under spinal anesthesia will be identified. After that, manual review of the anesthetic charts will follow. Detailed data on anesthetic technique will be retrieved and cases where conventional dose of hyperbaric bupivacaine was used will be included in further analysis. Further review of the charts will provide demographic data of the parturients, data on vital signs during anesthesia and dynamic of sensory block level. Attention will be paid to assure that identification of the patient would not be possible with data used in this study. All identifiable data used in data retrieval process and analysis will be accessible only for investigators.

Treatment:

Other: Spinal block level analysis

Other: data collection