The effect of adjuvant midazolam compared with fentanyl on the duration of spinal anesthesia with 0.5% bupivacaine in opium abusers

Comparison of the effect of adding midazolam versus fentanyl to intrathecal levobupivacaine in patients undergoing cesarean section: double-blind, randomized clinical trial

BACKGROUND

Many adjuvants are added to prolong the effects of spinal analgesia. We investigated the postoperative analgesic efficacy of the addition of midazolam or fentanyl to intrathecal levobupivacaine in women undergoing cesarean delivery.

METHODS

Eighty patients were randomly assigned to two groups (n = 40). Group M received 10 mg of 0.5% levobupivacaine plus 2 mg of midazolam. Group F received 10 mg of 0.5% levobupivacaine plus 25 μg of fentanyl. Assessments included motor and sensory block, APGAR score, time to first request for analgesia, postoperative pain score, total consumption of rescue analgesics, and adverse effects.

RESULTS

Sensory blockade was prolonged in Group M compared with Group F (215.58 ± 27.94 vs. 199.43 ± 19.77 min; p = 0.004), with no differences in other characteristics of the spinal block in intraoperative hemodynamics or APGAR score. The mean time to first request for rescue analgesia was longer in Group M (351.45 ± 11.05 min) than in Group F (268.83 ± 10.35 min; p = 0.000). The median total consumption of rescue analgesics in the first 24 hours postoperatively was 30 mg in Group M vs. 60 mg in Group F (p = 0.003). The median Visual Analog Scale (VAS) scores were lower in Group Ethan in Group F from the 8th to the 12th hour postoperatively, with no differences between the groups at other time points. The incidence of adverse effects was higher in Group F than in Group M.

CONCLUSION

Intrathecal midazolam (2 mg) was superior to intrathecal fentanyl (25 μg) in increasing the duration of the sensory blockade and postoperative analgesia with lower postoperative pain scores and decreasing the incidence of adverse effects.

Cerebrospinal Fluid and Spinal Anesthesia Parameters in Healthy Individuals versus Opium-addict Patients during Lower Limb Surgery

Background

Studies have reported lower pain threshold, spinal anesthesia duration, and level of sensory block in addicts compared to non-addict patients undergoing spinal anesthesia for surgery. Moreover, blood gas and cerebrospinal fluid (CSF) were likely to be affected as well. The aim in the present study is to evaluate CSF and spinal parameters in addict versus non-addict patients during lower limb surgery.

Methods

In this case-control study, 22 opium addicts and 22 sex- and age- matched non-addicts undergoing lower limb surgery under spinal anesthesia were included. The CSF parameters, venous blood gas (VBG), and sensory and motor block findings were compared between the groups.

Findings

The addict and non-addict patients were similar regarding CSF and blood gas parameters except higher pH in VBG (7.39 ± 0.06 vs. 7.33 ± 0.11, P = 0.030) and CSF (7.39 ± 0.06 vs. 7.33 ± 0.11, P = 0.030) for addict patients. The addict patients had significantly later onset of sensory block (5.72 ± 1.57 vs. 3.16 ± 0.93 minutes, P < 0.001) and shorter motor block duration (137.72 ± 11.51 vs. 149.09 ± 14.44 minutes, P = 0.006), with no significant difference in the sensory block duration and motor block onset.

Conclusion

Addict patients have delayed onset of sensory block with shorter duration of motor block and lower sensory block level. Among the blood gas and CSF markers, only pH was significantly higher in addict patients, needing further evaluations; however, it seems that addiction has no significant effect on these parameters.

B. S, Pandarpurkar S, Jajee P. Intrathecal Midazolam as an Adjuvant in Pregnancy-Induced Hypertensive Patients Undergoing an Elective Caesarean Section: A Clinical Comparative Study

Background

A pain-free postoperative period is essential following a caesarean section so new mothers may care for and bond with their neonates. Intrathecal adjuvants are often administered during this procedure to provide significant analgesia, but they may also have bothersome side effects. Intrathecal midazolam produces effective postoperative analgesia with no significant side effects.

Objectives

This prospective, randomized, double-blind study was designed to compare the analgesic efficacy and safety of intrathecal midazolam vs. plain bupivacaine as an adjunct to bupivacaine in pregnancy-induced hypertension patients scheduled for elective caesarean section.

Methods

Sixty patients diagnosed with pregnancy-induced hypertension on regular treatment who were scheduled for a caesarean section were randomly allocated into two groups: a control group (Group BC, n = 30) and a midazolam group (Group BM, n = 30). Both groups received 10 mg (2 mL) of 0.5% hyperbaric bupivacaine. Group BC received 0.4 mL of distilled water, while group BM received 0.4 mL (2 mg) of midazolam intrathecally. The duration of postoperative analgesia, analgesic requirements during the first 24 hours after surgery, onset times and durations of sensory and motor blocks, incidence of hypotension, vasopressor requirements, and side effects were recorded.

Results

Postoperative analgesia was significantly longer in the midazolam group compared to the control group (201.5 minutes vs. 357.6 minutes). The mean onset times of the sensory and motor blocks were significantly faster (P < 0.01) in the midazolam group compared to the control group. The mean times to attain the maximum sensory level and motor blocks were also significantly faster in the midazolam group compared to the control group (P < 0.05). The incidence of hypotension was 6.6% in the midazolam group and 36.6% in the control group, which was highly significant. In addition, the number of patients with side effects was significantly lower in the midazolam group compared to the control group.

Conclusions

Intrathecal midazolam 2 mg provides significantly longer and effective postoperative analgesia with no side effects.

A randomised controlled trial comparing the effect of adjuvant intrathecal 2 mg midazolam to 20 micrograms fentanyl on postoperative pain for patients undergoing lower limb orthopaedic surgery under spinal anaesthesia

BACKGROUND

Intrathecal adjuvants are added to local anaesthetics to improve the quality of neuraxial blockade and prolong the duration of analgesia during spinal anaesthesia. Used intrathecally, fentanyl improves the quality of spinal blockade as compared to plain bupivacaine and confers a short duration of post-operative analgesia. Intrathecal midazolam as an adjuvant has been used and shown to improve the quality of spinal anaesthesia and prolong the duration of post-operative analgesia. No studies have been done comparing intrathecal fentanyl with bupivacaine and intrathecal 2 mg midazolam with bupivacaine.

OBJECTIVE

To compare the effect of intrathecal 2mg midazolam to intrathecal 20 micrograms fentanyl when added to 2.6 ml of 0.5% hyperbaric bupivacaine, on post-operative pain, in patients undergoing lower limb orthopaedic surgery under spinal anaesthesia.

METHODS

A total of 40 patients undergoing lower limb orthopaedic surgery under spinal anaesthesia were randomized to two groups. Group 1: 2.6mls 0.5% hyperbaric bupivacaine with 0.4mls (20micrograms) fentanyl Group 2: 2.6mls of 0.5% hyperbaric bupivacaine with 0.4mls (2mg) midazolam.

RESULTS

The duration of effective analgesia was longer in the midazolam group (384.05 minutes) as compared to the fentanyl group (342.6 minutes). There was no significant difference (P 0.4047). The time to onset was significantly longer in midazolam group 17.1 minutes as compared to the fentanyl group 13.2 minutes (P 0.023). The visual analogue score at rescue was significantly lower in the midazolam group (5.55) as compared to the fentanyl group 6.35 (P - 0.043).

CONCLUSION

On the basis of the results of this study, there was no significant difference in the duration of effective analgesia between adjuvant intrathecal 2 mg midazolam as compared to intrathecal 20 micrograms fentanyl for patients undergoing lower limb orthopaedic surgery.

Intrathecal magnesium sulfate as a spinal adjuvant in two different doses, combined with 0.5% heavy bupivacaine for infraumbilical surgeries

The spinal anesthesia has the definitive advantage that profound nerve block can be produced in a large part of the body by the relatively simple injection of a small amount of local anesthetic.

The Effect of Adding Sufentanil to 0.5% Hyperbaric Bupivacaine on Duration of Brachial Plexus Blockade in Chronic Opium Abusers: a Randomized Clinical Trial

Background:

Anesthesia induction in patients with current substance abuse can be a challenge for anesthesiologists.

Objectives:

This study aimed to evaluate the effect of adding Sufentanil to Bupivacaine on duration of brachial plexus nerve block.

Patients and Methods:

One hundred and twenty patients with (Groups C and D) and without (Groups A and B) a history of opium abuse (60 in each group) scheduled for elective upper extremity procedures were randomly assigned to either receive 30 mL bupivacaine alone (Groups A and C) or in combination with additional 10 µg sufentanil (Groups B and D). An ultrasound-guided technique was applied to perform upper extremity brachial plexus blockade. The onset and duration of sensory and motor blocks were recorded and compared between the four groups.

Results:

The duration of sensory and motor block were significantly less in Group C (537.0 ± 40.1 minutes, 479.0 ± 34.8 minutes) and the longest duration of sensory and motor block was observed in group B (705.0 ± 43.8 minutes, 640.0 ± 32.5 minutes). The duration of sensory and motor block in Group B (705.0 ± 43.8 minutes, 640.0 ± 32.5 minutes) was longer and statistically higher than group A (619.5 ± 48.0 minutes, 573.2 ± 31.5 minutes), the same trend was observed in group D (598.6 ± 53.2 minutes, 569.3 ± 39.9 minutes) over group C (537.0 ± 40.1 minutes, 479.0 ± 34.8 minutes) (P < 0.001, one-way ANOVA).

Conclusions:

The length of sensory and motor blockade is shorter in chronic opioid abusers. Adding 10 µg sufentanil to hyperbaric bupivacaine in opium abusers lengthened the sensory and motor block duration.

Is the pharmacokinetics of bupivacaine equivalent after lumbar epidural administration through a needle or a catheter in male and female adults?

We assessed possible pharmacokinetic modifications due to different epidural injection techniques using either a needle or a catheter. Adult patients (n=23) undergoing lower abdominal or lower extremity surgery were randomly assigned a single bupivacaine epidural injection anesthesia (0.5%, 15 mL, 0.3 mL/s) through needle or catheter device. Plasma bupivacaine concentration was quantified using a validated HPLC method and non-compartmental pharmacokinetic parameters estimated. CMAX and TMAX were similar in both groups: 952 ± 346 ng/mL, 0.65 ± 0.5 1h in the needle group; 810 ± 307 ng/mL, 0.43 ± 0.29 h in the catheter group respectively. Plasma AUC₀→∞ was also similar in both groups: 3868 ± 1687 ngh/mL for needle versus 4096 ± 1748 ngh/mL using catheter. The catheter group showed slower disposition than the needle group: t₁/₂=3.9 ± 2.3 h, MRT=6.0 ± 3.1 h versus 2.7 ± 1.03 h and 4.5 ± 1.2 h with needle administration respectively though it did not reach statistical significance, Cl/F and V/F were also similar. Lastly, female patients showed significant longer t1/2 after administration through catheter (5.7 ± 2.0 h) than needle (2.7 ± 0.6 h) group (P=0.0279). The device type does not affect the pharmacokinetics which is similar in both groups although sex-based differences might exist.

Reduction in labor pain by intrathecal midazolam as an adjunct to sufentanil

BACKGROUND

Anesthesia today has strived to decrease labor pain in a tolerable and controllable fashion. Intrathecal midazolam has been introduced as an adjunct to analgesics. The study was planned to assess the efficacy, safety and duration of analgesia produced by intrathecal midazolam adjunct to sufentanil in decreasing labor pain.

METHODS

In a randomized clinical trial 80 parturient included in the study. The two groups were matched for age, cervical dilation, gravid, gestational age, and other demographic characteristics. Combination of sufentanil and midazolam administered intrathecally to experimental group and compared to sufentanil group. Time to reach maximum block, and pain score was measured and recorded.

RESULTS

Groups were matched for age and weight and other demographic characteristic. No significant adverse effect was seen in both groups including decrease in Apgar score. Duration of analgesia was 92.0 ± 12.7 in sufentanil group and 185.2 ± 15.2 minutes in midazolam and sufentanil group which was significantly different (P = 0.002). Numeric rating scale score was significantly lower in midazolam group compare to sufentanil group at 120 min (P = 0.01), 150 min (P = 0.0014), and 180 min (P = 0.001).

CONCLUSIONS

Intrathecal midazolam as an adjunct to opioid could significantly enhance analgesia in labor pain with no significant adverse effect. Intrathecal injection of midazolam is an appropriate alternative to parenteral or epidural analgesia in small hospital settings.

Effect of intravenous patient controlled ketamine analgesiaon postoperative pain in opium abusers

Background:

Acutepostoperative pain is among the worst experience that patient scan undergo, and many analgesics have been used to suppress it; especially in chronic opium abusers. Ketamine is an N-methyl-D-aspartate antagonist analgesic, having both anesthetic and analgesic properties, which are not affected to the same extent in chronic opium abusers.

Objectives:

In this study, we assessed the analgesic effects of ketamine added to morphine as a patient-controlled analgesia method for acute pain management, compared with a placebo, inchronic maleopium abusers.

Patients and Methods:

After institutional review board approval for ethical considerations, a randomized double-blinded placebo controlled clinical trial was conducted. A total of 140 male patients aged 18-65 years, undergoing orthopedic surgery, were entered into the study after matching inclusion and exclusion criteria. All patients received the same anesthesia method; while the first group received ketamine (1mg/mL) and morphine (0.5 mg/mL) as a patient-controlled analgesia (70 patients), the second group received morphine (0.5 mg/mL) plus normal saline (70 patients). P value less than 0.05 was considered statistically significant.

Results:

The ketamine and morphine group of patients experienced less postoperative pain and required less postoperative rescue analgesia. However, the unwanted postoperative side effects were nearly the same; although increased levels of postoperative nausea and vomiting were observed in the ketamine and morphine group

Conclusions:

This study demonstrated improved analgesic effects after using intravenous patient controlled analgesia with ketamine on postoperative pain in opium abusers.

Comparison of postoperative analgesic effect of intrathecal clonidine and fentanyl added to bupivacaine in patients undergoing cesarean section: a prospective randomized double-blind study

Objectives. To compare the analgesic efficacy of intrathecal clonidine and fentanyl added to bupivacaine after cesarean section. Methods. Ninety patients scheduled for cesarean section under spinal anesthesia were randomly allocated to one of the three following groups to receive bupivacaine 10 mg combined with 75 µg clonidine (group C), bupivacaine 10 mg combined with 0.5 mL fentanyl (group F), and bupivacaine 10 mg combined with 0.5 mL distilled water (group P), intrathecally. The time to first analgesic request, analgesic requirement in the first 24 hours after surgery, sensory and motor blockade onset time, duration of sensory and motor blockade, the incidence of hypotension, ephedrine requirements, bradycardia, and hypoxemia were recorded. Results. The duration of anesthesia in clonidine group (275.10 ± 96.09) was longer compared to the placebo (211.73 ± 74.80) and fentanyl (192.33 ± 30.36) groups. This difference between group C versus F (P = 0.006) and P groups (P < 0.001) was significant. Similarly, the mean time to first analgesic request was also longer in group C (519.44 ± 86.25) than in groups F (277.88 ± 94.25) and P (235.43 ± 22.35 min). This difference between group C versus F (P < 0.001) and P groups (P < 0.001) was significant. Conclusion. Intrathecal clonidine 75 µg with bupivacaine prolonged the time to first analgesic request compared to fentanyl; however, the total analgesic consumption within the first 24 h postoperative was similar in fentanyl and clonidine groups following cesarean section. This trial is registered with ACTRN12611000909921 and ClinicalTrials.gov NCT01425658.