The routine assessment of fluid status depends on clinical evaluation and invasive monitoring. The clinical assessment lacks objectivity and the invasive monitoring carries risks. Point of care ultrasound (POCUS) parameters can be useful as early markers of fluid status and were used in safe fluid assessment in term pregnancy and preeclampsia.

Fluid therapy in preeclamptic patients presents a challenge. volume expansion may precipitate pulmonary edema while fluid restriction may worsen renal function and may aggravate post-spinal hypotension during cesarean section.

Pre-eclampsia predisposes to maternal mortality. It presents a serious hypertensive disorder during pregnancy which may progress rapidly to serious complications, including the death of both mother and fetus The optimal fluid management strategy constitutes a cornerstone in the management. The Royal College of Obstetricians and Gynecologists (RCOG) guidelines for severe pre-eclampsia recommend restrictive fluid therapy, in keeping with the absence of evidence favoring volume expansion. Restrictive management is advocated by The Society of Obstetric Medicine of Australia and New Zealand (SOMANZ) with additional fluid administration only recommended before intravenous hydralazine, regional anesthesia, immediate delivery, or in oliguric patients where a volume deficit is suspected.

Overall, limited evidence exists regarding the effectiveness of ultrasound assessment of the IVC collapsibility index to guide pre-operative fluid management in critically ill pre-eclamptic patients. A meta-analysis stated that few research trials are available in the obstetric population. Some studies suggest that it can accurately predict fluid responsiveness, but others argue that it may not be helpful.

Our trial is the first trial that compares the efficacy of IVCCI-guided perioperative fluid therapy against standard fluid therapy guided by clinical parameters in critically ill pre-eclamptic patients.

Inclusion Criteria:

• Critically ill pre-eclamptic patients for cesarean section

Exclusion Criteria:

• Patient refusal
• severe cardiovascular disease ( ejection fraction < 40 mmHg ), tricuspid regurge.
• contraindication for spinal anesthesia.
• failure to perform spinal anesthesia.
• severe hepatic.
• renal dysfunction

de-identified individual participant data (IPD) will be available to other researchers

After publishing the protocol in a relevant journal. will be available through that journal and according to the regulation

the published protocol will be either free or through a subscription according to the journal.

• The care provider intraoperative; both the anesthesiologist and the obstetrician will be blinded regarding the intervention.
• The anesthetic residents who will assess the outcome of hypotension are blind regarding the group allocation