Different Preloads for Prevention of Hypotension in Patients Undergoing Elective CS Under Intrathecal Anesthesia

Different Preloads for Prevention of Hypotension in Patients Undergoing Elective CS Under Intrathecal Anesthesia

Crystalloid Versus Crystalloid and Colloid Combination Preload for Prevention of Hypotension in Patients Undergoing Elective Caesarean Section Under Intrathecal Anesthesia

The aim of this study was to compare between crystalloid versus crystalloid and colloid combination preloads for prevention of hypotension following intrathecal anaesthesia in patients undergoing elective Caesarean section. To examine weather baseline perfusion index could predict the incidence of intrathecal-induced hypotension during Caesarean section.

Intrathecal anesthesia is the most commonly used technique for elective Caesarean section all over the world. One of the most common complications of this technique is hypotension. It's incidence is more than 80% without any prophylactic measures, this hypotension has adverse effects on both mother ( causing nausea and vomiting ) and foetus ( causing acidosis and neurological defects ). This complication can be managed by several ways like fluid therapy, usage of vasopressors or combination between both of them. Among the type of fluids ( crystalloid or colloid ) it's still not known which one of them is better. Crystalloid has a short intravascular half-life because of its rapid distribution into the interstitial space. On the other hand colloid remains longer within the intravascular space. Change in baseline peripheral vascular tone due to pregnancy may affect the degree of such hypotension. The perfusion index ( PI ) derived from a pulse oximeter has been used for assessing peripheral perfusion dynamics due to changes in peripheral vascular tone.

This group will receive 500 ml of 6% hydroxyethyl starch ( Voluven ) and 500 ml Ringer's solution as a preload

500 ml of voluven will be given in combination with 500 ml Ringer's solution as a preload in the other group.

Inclusion Criteria: Age : 18-40 years ASA 1&2 Exclusion Criteria: Patients with morbid obesity. Pre-existing or pregnancy-induced hypertension. Known cardiovascular or cerebrovascular disease. Abnormal CTG tracing. Any other contraindications for intrathecal anaesthesia.

Ripolles Melchor J, Espinosa A, Martinez Hurtado E, Casans Frances R, Navarro Perez R, Abad Gurumeta A, Calvo Vecino JM. Colloids versus crystalloids in the prevention of hypotension induced by spinal anesthesia in elective cesarean section. A systematic review and meta-analysis. Minerva Anestesiol. 2015 Sep;81(9):1019-30. Epub 2014 Dec 11.

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