English

Abstract

BACKGROUND: Spinal anesthesia is the more commonly administered procedure for pelvic, lower abdominal and lower limb procedures. Hypotension is the most common complication of spinal anesthesia. It is a common practice to give intravenous fluids, usually crystalloids, prior to centro neuraxial block in order to prevent hypotension and this is usually referred as preloading. AIMS: Compare the efficacy of preloading with crystalloid to that of colloids in reducing the incidence and severity of hypotension in spinal anesthesia for lower abdominal surgery and also to find out if hydroxyl ethyl starch (HES) is a better colloid than polygelatin. STUDY DESIGN: The study population included 150 patients belonging to either sex undergoing elective lower abdominal surgeries under spinal anesthesia. METHODS AND MATERIAL: One hundred and fifty ASA I and II patients posted for lower abdominal surgeries under spinal anesthesia were randomly allocated to receive either 10mL/Kg of HES (Group A), 10mL/Kg of polygelatin (Group B) or 10mL/Kg of Ringer's lactate solution as preloading solution. Heart rate, systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) were recorded once in two minutes for the first ten minutes and once in five minutes for the next fifty minutes. The incidence of hypotension and the mean dose requirement of mephentermine were noted after spinal anesthesia. STATISTICAL METHODS: The analysis of variance to find the significance difference of pulse rate, SBP and MAP between the three groups of patients. The Post hoc test by Tukey to find the pair wise significance between the three groups. The Chi-square test to find the significance of proportions of mephentermine dose requirement between the three groups. RESULTS: The incidence of hypotension was 9 of 50 (18%) in Group A, 17 of 50 (34%) in Group B and 27 of 50 (54%) in group C. The mephentermine bolus requirements were also less in group A (9 times) when compared to group B (18times) and group C (32 times), which was statistically significant. INTERPRETATION AND CONCLUSION: HES reduced the incidence of hypotension after spinal anesthesia and required lesser mean dose requirements of mephentermine when compared to polygelatin and ringers lactate. It can be concluded from the present study that colloids offset hypotension and hypovolemia more effectively than crystalloids. Also it can be concluded that hydroxyethyl starch is a better