From the Guidelines
Prespinal ondansetron is recommended for preventing nausea and vomiting during elective lower segment cesarean section (LSCS) under spinal anesthesia, as it has been shown to be effective in reducing the incidence of nausea and vomiting by blocking 5-HT3 receptors. The evidence from a Cochrane review study 1 demonstrates that 5-HT3 antagonists, such as ondansetron, are effective in reducing intraoperative nausea and vomiting. Additionally, a meta-analysis 1 reported that combination regimens, including 5-HT3 antagonists, are significantly more effective than 5-HT3 alone in preventing nausea and vomiting.
The use of ondansetron as an antiemetic agent is supported by the guidelines for postoperative care in cesarean delivery, which recommend a multimodal approach to nausea and vomiting prevention 1. The guidelines also highlight the importance of preventing nausea and vomiting, as it can increase the risk of aspiration, prolong the duration of surgery, and delay discharge from hospital 1.
Key points to consider when using prespinal ondansetron for elective LSCS include:
- The typical dose of ondansetron is 4-8 mg administered intravenously 5-10 minutes before spinal anesthesia
- Ondansetron has a good safety profile in pregnancy with minimal side effects and no known adverse effects on the fetus
- The use of ondansetron can reduce the need for vasopressors like phenylephrine or ephedrine, which can affect uteroplacental blood flow
- A multimodal approach to nausea and vomiting prevention, including the use of ondansetron, is recommended for elective LSCS under spinal anesthesia 1.
From the Research
Evidence for Prespinal Ondansetron in Elective LSCS
The use of prespinal ondansetron for elective lower segment cesarean section (LSCS) has been studied in several research papers. The evidence suggests that ondansetron can be effective in reducing nausea and vomiting during and after cesarean section under spinal anesthesia.
Studies on Ondansetron
- A study published in 1999 2 found that ondansetron reduced the incidence of vomiting and the severity of nausea during cesarean section under spinal anesthesia.
- Another study published in 2017 3 found that ondansetron was effective in preventing postspinal shivering, nausea, and vomiting during lower segment cesarean section under spinal anesthesia.
- A study published in 2015 4 compared the effect of intravenous dexamethasone, intravenous ondansetron, and their combination on nausea and vomiting in cesarean section with spinal anesthesia, and found that the combined use of dexamethasone and ondansetron increased the antiemetic efficacy.
- A study published in 1996 5 found that prophylactic ondansetron was effective in reducing the incidence of nausea and vomiting in cesarean section patients under epidural anesthesia.
- A study published in 2013 6 found that the addition of metoclopramide or its combination with ondansetron to a prophylactic phenylephrine infusion provided improved intraoperative nausea and vomiting prophylaxis compared with phenylephrine infusion alone.
Key Findings
- Ondansetron reduces the incidence of vomiting and the severity of nausea during cesarean section under spinal anesthesia 2.
- Ondansetron is effective in preventing postspinal shivering, nausea, and vomiting during lower segment cesarean section under spinal anesthesia 3.
- The combined use of dexamethasone and ondansetron increases the antiemetic efficacy 4.
- Prophylactic ondansetron is effective in reducing the incidence of nausea and vomiting in cesarean section patients under epidural anesthesia 5.
- The addition of metoclopramide or its combination with ondansetron to a prophylactic phenylephrine infusion provides improved intraoperative nausea and vomiting prophylaxis 6.