Comparison of Dexmedetomidine as an Adjuvant to Ropivacaine Vs. Ropivacaine Alone in Lower Abdominal & Lower Limb Surgeries

Introduction: For lower abdominal and lower limb surgeries,epidural anesthesia technique of central neuraxial blockade isin used very commonly as this technique avoids theshortcomings and drawbacks of general anesthesia like airwaymanipulation and poly-pharmacy along with other untowardeffects like postoperative nausea and vomiting while ruling outneed for additional intravenous analgesics.Methodology: In our study two groups were included that wasgroup R and group RD. 50 cases were included in in eachgroups. This study was conducted in the Department ofAnesthesia, Carrier Institute of Medical Sciences & Hospital,Lucknow, U.P., India.Study Duration: The duration of study was over a period of sixmonths.Result: In our study two groups were included that was groupR and group RD. 50 cases were included in in each groups.The mean duration of motor blockade is 149.00±14.21mins ingroup R and 233.70±15.26 minutes in group RD; alsosignificant difference between the group (p=0.001).Conclusion: This study suggested that Dexmedetomidinewhen added to Ropivacaine produces profound synergisticeffect and prolongs motor and sensory blockade.

Comparative Study between Ropivacaine and Ropivacaine Plus Fentanyl for Spinal Anesthesia

Introduction: Spinal anesthesia is preferred over general anesthesia due to the ease of administration, minimal systemiceffects, and reduced post-operative morbidity. A number of anesthetic agents and adjuvants have been tried over the years, toachieve optimal effects. This study compares the efficacy of ropivacaine versus ropivacaine plus fentanyl as spinal anesthetics.Materials and Methods: This study was carried out on 100 American Society of Anaesthesiologists Grades I and II patients,having no comorbidities and scheduled for surgery of up to 200 min. They were randomly divided into two Groups: Group I(Ropivacaine) and Group II (Ropivacaine and Fentanyl). Intraoperative and post-operative vitals, analgesic parameters, andside effects were monitored.Results: The onset of both sensory and motor blockade was faster, and the duration of the blockade was longer with theaddition of fentanyl to ropivacaine. Ropivacaine is a safe drug in terms of cardiorespiratory stability and other side effects. Theaddition of fentanyl did not alter the beneficial side effect profile of ropivacaine.Conclusion: Ropivacaine is a safe anesthetic in terms of cardiorespiratory stability and side effects. The addition of fentanyl toropivacaine significantly potentiates the block, both sensory and motor, without altering the beneficial effects of cardiorespiratorystability and side effect profile.

A randomized prospective comparative study of nerve stimulator and ultrasonogram in popliteal sciatic nerve block for ankle and foot surgeries.

Background: Regional blocks in the field of anaesthesia were done traditionally with paraesthesia technique. To overcome the demerits with paraesthesia technique, nerve locator was applied for nerve blocks. Later, the application of ultrasonogram for regional blocks got the real time imaging of the nerves and drug administration. This resulted in publications of numerous studies with variable results. Therefore we planned to compare ultrasonogram and nerve locator in popliteal sciatic nerve block in our population. Methods: A prospective, randomized, observer blinded study was planned to compare the nerve stimulator (Group N) and ultrasound (Group U) on duration of „block technique‟, number of needle reinsertions in popliteal sciatic nerve block for ankle and foot surgeries. We included all consented patients aged ≥18 years of both genders belonging to ASA I to III and excluded pregnant mothers, diabetes mellitus, neuropathy, chronic opioid use, positioning difficulty, coagulopathy, nerve block contraindications, local anaesthetic allergic patients. Results: The duration of block technique in Group U = 262.00 ± 108.36 Seconds and Group N = 715.16 ± 234.66 Seconds with statistically significant P value = 0.0001. The average number of needle reinsertions in Group N = 6.05 ± 2.31 and Group U = 2.46 ± 1.11 with statistically significant p value of 0.0001. Therefore the time taken to perform the block and the number of needle reinsertions in Group U is shorter than the Group N. Conclusion: The duration of block technique and number of needle reinsertions are better with ultrasound. Though the onset of motor and sensory blockade were better with ultrasound success rate is not significantly different.

The Effect of Distal Tourniquet in the Axillary Brachial Plexus Block / 대한마취과학회지

BACKGROUND: We investigated the effect of distal tourniquet to the proximal spread of local anesthetics in the axillary brachial plexus block. METHODS: In this prospective, randomized, controlled trial, 60 patients undergoing elective surgery were divided into two equal groups; Group I (2% mepivacaine 20 ml plus 1% lidocaine 20 ml with 250 mmHg of distal tourniquet) and Group II (2% mepivacaine 20 ml plus 1% lidocaine 20 ml alone). Patients were left for 30 minutes after an axillary brachial plexus block with paresthesia and single injection technique. Sensory blockades were evaluated by pin prick test at each nerve dermatome. RESULTS: There was no significant difference of sensory blockade in radial nerve, but there were significant differences of sensory blockade in ulnar, median, musculocutaneous, medial antebrachial cutaneous, and axillary nerves (P < 0.05). CONCLUSIONS: Our findings suggest that the quality and effect of axillary brachial plexus block in group with distal tourniquet is better than the control group.

Comparison of Bupivacaine and Normal Saline for Epidural Top-up on Sensory Blockade Level during Combined Spinal Epidural Anesthesia / 대한마취과학회지

BACKGROUND: An increase in the maximum level of sensory blockade by epidural 'top-up' in combined spinal epidural anesthesia may be explained by two mechanisms; a volume effect, compressing the dural sac, and a local anesthetic effect. This study was undertaken to investigate the relative importance of these factors. METHODS: Eighty patients about to undergo lower limb surgery under combined spinal epidural anesthesia were randomly assigned to four groups. Using the needle-through-needle technique, all patients received a subarachnoid injection of 8 mg of heavy bupivacaine through an epidural catheter. At 30 minutes after subarachnoid injection, an epidural top-up was given according to a randomization code. Experimental groups received 10 ml of saline, 10 ml of bupivacaine 0.25%, or 10 ml of bupivacaine 0.5%. The control group received no epidural top-up. The level of sensory blockade was checked by using the pinprick test at 5, 10, 15, 20, 25 and 30 minutes after subarachnoid injection, and at 5, 10, 15, 20, 25 and 30 minutes after epidural top-up. Blood pressure, heart rate and the incidence of side effects such as hypotension, bradycardia, nausea, and high block were analyzed. RESULTS: There was no significant difference in maximum level of sensory block among the 10 ml saline, 10 ml bupivacaine 0.25% or 10 ml bupivacaine 0.5% treated groups during epidural phase. Although blood pressure and heart rate were decreased, there were no differences among experimental groups during epidural phase. The most common side effect during combined spinal epidural anesthesia was hypotension. The incidence of bradycardia and high sensory block (above T4 dermatome level) was similar among the groups. CONCLUSIONS: After the maximum level of sensory blockade due to subarachnoid injection has been established, an epidural top-up with 10 ml of saline or 10 ml of either 0.25% or 0.5% bupivacaine did not significantly increase the level of subarachnoid block in patients with lower extremity surgery. The author concludes the there were no differences among groups with regard to the volume effect and local anesthetic effect in terms of the sensory blockade level during the epidural phase. However, blood pressure and heart rate in the epidural top-up groups reduced with operation time.

Effect of Single Epidural Saline at 15 Minutes after the Spinal Anesthetic Administration on Spinal Sensory Blockade Level / 대한마취과학회지

BACKGROUND: The effect of epidural local anesthetics on the spinal anesthesia is not well known during the combined spinal epidural anesthesia (CSE). But, Blumgart and his colleagues suggested that epidural volume load affect spinal sensory blockade level. This study was designed to investigate the effect of extradural injection of normal saline on the level of the subarachnoid block according to the time of the extradural saline injection. METHODS: Sixty patients undergoing lower abdominal and lower extremity operation were involved in our study. After performing subarachnoid block with 12 mg of hyperbaric tetracaine, divided into as follows: Group 1 (n=20), received only spinal anesthesia; Group 2 (n=20), received 15 ml of epidural saline immediately after spinal anesthetic administration; Group 3 (n=20), received 15 ml of epidural saline at 15 minutes after spinal anesthetic administration. Sensory blockade level was checked by pinprick test at 5, 10, 15, 20, 25, 30, 40, 60 and 90 minutes. Blood pressure, heart rate and incidence of complications such as hypotension, bradycardia, nausea and high spinal block were also measured. RESULTS: The maximal sensory blockade level of Group 2 was higher than those of Group 1 and Group 3 (p0.05). CONCLUSIONS: From the results obtained, epidural volume load at the 15 minutes after spinal anesthetic administration did not affect the sensory blockade level of spinal anesthesia during CSE.

Effect of Single Epidural Saline on Spinal Sensory Blockade Level during Combined Spinal Epidural Anesthesia / 대한마취과학회지

BACKGROUND: Combined spinal epidural anesthesia (CSE) is used for obtaining adventages of both spinal and epidural anesthesia. But it might be suspected that epidural volume load affect spinal sensory blockade level during CSE. METHODS: Eighty patients undergoing lower abdominal and lower extremity operation were involved in our study. Subarachnoid block with 12mg of tetracaine was established in all patients. Four groups were studied. Group 1 (n=20), the control, received only spinal anesthesia. Group 2 (n=20), group 3 (n=20) and group 4 (n=20) received 10, 15 and 20 ml of epidural saline immediately after spinal anesthetic administration. Sensory blockade level was checked by pinprick test at 5, 10, 15, 20, 25, 30, 40, 60 and 90 minutes. Blood pressure, heart rate and incidence of complications such as hypotension, bradycardia, nausea and high block were measured. RESULTS: The sensory blockade level of groups 3 and 4 was higher than group 1 (p<0.05). Blood pressure and heart rate were not different compared with each other. The incidence of complications, except that higher block above T4 in group 4 was more than in group 1 (p<0.05), were not different when compared with each other. CONCLUSIONS: Epidural saline above 15 ml may affect sensory blockade level of spinal anesthesia during CSE.

Minor Factors Influencint to the Sensory Blockade Level of Spinal Anesthesia at the L2, 3 Interspace / 대한마취과학회지

BACKGROUND: Many factors affecting the spread of spinal anesthesia have been investigated. But L3-4 or L4-5 interspace was choosen which was known as the site of buffering, in their study. We investigated the effect of some of these factors on sensory blockade level by using L2-3 interspace. METHODS: Eightyfive patients, ASA physical status I - Il, were involved in our study. Sensory blockade level was checked with pinprick test at 10 minutes and 30 minutes. The effect of age, sex, height, weight, CSF pressure and pressure difference generated when full flexed and non-full flexed lateral position on sensory blockade level was studied whereas other factors such as puncture technique, dosage and concentration of drug and patients position after injection, were kept constant under the same condition. And also studied the effect of degree of flexion at injection on the sensory blockade level. RESULTS: Height and CSF pressure were correlated with sensory blockade level at 10 minutes after injection(R2=0.14, P<0.01). Only height was correlated with sensory blockade level at 30 minutes after injection(R2=0.09, P<0.0l). CONCLUSIONS: Only height was correlated with sensory blokade level at 30 minutes. So, height might be considered as the most impressive minor factor affecting the extent of sensory blockade level.

Does the Temperature of 0.5% Plain bupivacaine Affect the Sensory Level in Spinal Anesthesia? / 대한마취과학회지

The level of sensory blockade in spinal anesthesia is determined by the distribution of local anesthetics within cerebrospinal fluid (CSF) which is affected by the density of local anesthetics. Temperature is one of the factors which can influence the density of local anesthetics. The level of sensory blockade in spinal anesthesia may be altered by the density change of local anesthetics and by the time needed for thermal equilibration in CSF, depending on the storage temperature of local anesthetics. A study was conducted at Inchon Severance hospital on 20 elective surgery patients under spinal anesthesia, to compare the clinical differences between two groups stored at different temperatures. Group I was used 0.5% plain bupivacaine 3 ml (15 mg) stored in a refrigerator for longer than 24 hours and group II was used that stored in operating room temperature. The results were as follows : The level of sensory blockade in group II was significantly higher than that of group I, 3 minutes after spinal anesthesia by segmental level of sensory loss to pinprick test. The degree of motor blockade was significantly greater by Bromage scale in group II than in group I at 2 minutes after spinal anesthesia, but no significant difference was observed after 5 minutes. When 15 minutes elapsed, the complete motor blockade of lower extremities was observed in both groups. The onset of sensory block was significantly faster in group II(3.1+/-0.2 min) than in group I (5.2+/-0.5 min). The onset of maximum sensory block was also significantly faster in group II(9.5+/-0.5 min) than in group I (14.0+/-1.5 min). The maximum sensory block level was significantly higher in group II(T6.7+/-0.3 dermatome) than in group I (8.2+/-0.3 dermatome). However, the regression time was not significantly different between group I (122.0+/-3.8 min) and group II (117.2+/-6.0 min). The above results showed that when 0.5% plain bupivacaine stored in room temperature was used in spinal anesthesia, gave higher level of sensory blockade and faster onset than that kept in a refrigerator, which may due to the time difference needed for thermal equilibration in CSF.