Acta Scientific Neurology (ASNE) (ISSN: 2582-1121)

Research Article Volume 4 Issue 8

Comparison of Hyperbaric and Isobaric Solution of Bupivacaine in Spinal Anaesthesia

Arun R* and Girish Kumar J

Sree Uthradom Thirunal Academy of Medical Sciences (SUTAMS), Thiruvananthapuram, Kerala, India

*Corresponding Author: Arun R, Assistant Professor, Department of Anaesthesiology, Sree Uthradom Thirunal Academy of Medical Sciences (SUTAMS), Thiruvananthapuram, Kerala, India.

Received: June 11, 2021; Published: July 28, 2021


Aims: The primary objective of the study was to compare the efficacy of administration of isobaric versus hyperbaric bupivacaine for spinal anaesthesia in patients undergoing lower abdominal and lower limb surgeries. Administering hyperbaric solution intrathecally is advisable for lower abdominal surgeries as the drug was found to produce a high sensory block when compared with isobaric bupivacaine. The longer duration of analgesia and the more gradual fall in blood pressure seen with isobaric bupivacaine are definite advantages over hyperbaric preparations. The isobaric preparation is of much help in perineal and lower limb surgeries.

Objectives: We tried to compare the efficacy of both hyperbaric and isobaric preparations of bupivacaine and if possible to replace hyperbaric with isobaric solution.

Methods: 80 patients in the age group 20-60 years undergoing elective surgery and belonging to ASA grade I& II were studied. These patients were divided into 2 equal groups of 40 each-Group I as those who received hyperbaric bupivacaine and group II as those who received isobaric bupivacaine. In the case of qualitative data, percentage were calculated and the association between the variables was tested statistically with the help of Chi-square test. The equality of the mean values of the two groups was tested by applying Student’s t test.

Results: There was no statistical difference in outcome between the two groups in age, height, weight and sex. The mean number of segments blocked in the two groups appeared small, but it was statistically highly significant (P < 0.001). The isobaric group took 11.8 minutes as the time of latency of maximal spread compared to only 10.78 minutes in hyperbaric group (P < 0.01). While considering the duration of motor block, isobaric group necessitated 248.75 minutes whereas it was only 211.63 minutes in the hyperbaric group (P < 0.001). The duration of analgesia also was found to be greater with the isobaric group (P < 0.001).

Conclusion: The anaesthetic properties of isobaric and hyperbaric bupivacaine were compared after intrathecal injection undergoing lower abdominal, perineal and lower limb surgeries. Hyperbaric bupivacaine administered produced the highest spread of analgesia, up to T7. Isobaric solution resulted in spread of analgesia to T9 only. While motor block in the legs were good in both the cases, the onset was faster with the hyperbaric group. The longest duration of analgesia recorded was found to be greater with the isobaric group. The course of anaesthesia and recovery were uneventful in all patients of both the groups.

Keywords: Spinal Anaesthesia; Bupivacaine; Isobaric; Hyperbaric; Intrathecal


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Citation: Arun R and Girish Kumar J. “Comparison of Hyperbaric and Isobaric Solution of Bupivacaine in Spinal Anaesthesia”. Acta Scientific Neurology 4.8 (2021): 60-67.


Copyright: © 2021 Arun R and Girish Kumar J. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


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