Intrathecal anesthesia

Randomized controlled study comparing 2-chloroprocaine and bupivacaine for spinal anesthesia in gynecological surgeries

Background:

Ambulatory surgeries are increasing all over. While searching for an ideal anesthetic, the use of lidocaine was linked to a greater rate of transitory neurological symptoms and bupivacaine delays discharge due to a longer duration of motor blockade. 2-chloroprocaine (2CP) with a shorter duration of action is gaining popularity. We aimed to compare intrathecal bupivacaine and 2CP for the subarachnoid block for elective ambulatory gynecological surgeries.

Methods:

A single-blind study was conducted on 90 patients comparing 40 mg 2CP and 10 mg 0.5% bupivacaine heavy measuring pinprick sensation, motor block, time to ambulation, and voiding of urine so as to get ready for discharge.

Results:

In both groups, the beginning of sensory blockage occurred at a similar time, while motor blockade achieved was faster in the 2CP group. The resolution of motor blockade was 1.7 times faster in the 2CP group than in the bupivacaine group. Time taken for ambulation was delayed significantly in the bupivacaine group, i.e., 263.04 ± 29.08 min compared to the 2CP group, i.e., 225.44 ± 29.48 min which was a delay of almost 38 min. Voiding of urine was also delayed in the bupivacaine group by 60 min compared to the 2CP group and was significant finding leading to delay of discharge of patients. Adverse effects were comparable in both groups.

Conclusion:

Intrathecal preservative-free 2CP provides satisfactory surgical block, and has a considerably faster rate of block regression, resulting in earlier ambulation and voiding, allowing the patient to be discharged from the hospital sooner as compared to intrathecal bupivacaine.

A comparison of low dose hyperbaric levobupivacaine and hypobaric levobupivacaine in unilateral spinal anaesthesia

The aim of this study was to compare the clinical effects and characteristics of hyperbaric and hypobaric levobupivacaine for unilateral spinal anaesthesia. Sixty patients were randomly allocated into two groups to receive either 7.5 mg (1.5 ml) hyperbaric levobupivacaine 0.5% or 7.5 mg (4 ml) hypobaric levobupivacaine 0.1875% for elective arthroscopic surgery of the knee under spinal anaesthesia. The level and duration of sensory block, intensity and duration of motor block were recorded. Unilateral sensory block was observed in 27 patients (90%) in the hyperbaric group and 24 patients (80%) in the hypobaric group in the lateral position. After 15 minutes, patients were turned to supine to redistribute the spinal block toward the non-operative side, but spinal anaesthesia was still unilateral in 18 patients (60%) in the hyperbaric group and 10 patients (33%) in the hypobaric group (P = 0.038). Time to readiness for home discharge and complete recovery of sensory block were similar in both groups. In the hyperbaric group, the motor block scores were higher on the operative side during first 10 minutes than they were in the hypobaric group (P < 0.002). Motor block regression was faster in the hyperbaric group (P = 0.01). Hyperbaric and hypobaric levobupivacaine both provided satisfactory unilateral spinal anaesthesia with good haemodynamic stability for arthroscopic surgery, but with more frequent unilateral spinal anaesthesia in the hyperbaric group.

Spinal mepivacaine with fentanyl for outpatient knee arthroscopy surgery: a randomized controlled trial

BACKGROUND

The foremost limitation of local anesthetic solutions for spinal anesthesia in the outpatient setting is prolonged motor blockade and delayed ambulation. The purpose of this study was to determine if the addition of intrathecal fentanyl to low-dose spinal mepivacaine provides adequate anesthesia with shorter duration of functional motor blockade for ambulatory knee surgery compared with spinal mepivacaine alone.

METHODS

Following institutional review board approval and informed consent, 34 patients undergoing unilateral knee arthroscopy were enrolled in this study. The patients were randomly assigned to receive either 30 mg of isobaric mepivacaine 1.5% plus fentanyl 10 microg (M + F group) or 45 mg of isobaric mepivacaine 1.5% alone (M group) intrathecally. Postoperatively, the times to achieve sensory block regression to the S1 dermatome and to attain functional motor block recovery enabling ambulation were recorded. All assessments were blinded.

RESULTS

The time to completion of Phase I recovery was shorter in the M + F group (104.6 +/- 28.4 min) than in the M group (129.1 +/- 30.4 min; P = 0.023). Regression of sensory blockade to S1 was earlier in the M + F group (118.4 +/- 53.5 min) than in the M group (169.7 +/- 38.9 min; P = 0.003). Patients in the M + F group (176.4 +/- 40.3 min) were able to ambulate significantly earlier than those in the M group (205.6 +/- 31.4 min; P = 0.025). No cases of transient or persistent neurological dysfunction were noted.

CONCLUSIONS

When compared with 45 mg isobaric mepivacaine 1.5%, an intrathecal dose of 30 mg isobaric mepivacaine 1.5% plus 10 microg fentanyl produces reliable anesthesia, hastens block regression, shortens stay in Phase I recovery, and enables earlier ambulation for patients undergoing unilateral knee arthroscopy (Registration no. NCT00803725).

Intrathecal ropivacaine 5 mg/ml for outpatient knee arthroscopy: a comparison with lidocaine 10 mg/ml

PURPOSE

The aim of this prospective, randomised, blind study was to compare the evolution of spinal block produced with 50 mg lidocaine 10 mg/ml and 10 mg ropivacaine 5 mg/ml for outpatient knee arthroscopy.

METHODS

Thirty outpatients undergoing knee arthroscopy received 50 mg of lidocaine 10 mg/ml (n=15) or 10 mg of ropivacaine 5 mg/ml (n=15) intrathecally. The evolution of spinal block was recorded until home discharge, while the occurrence of transient neurologic symptoms (TNS) was evaluated through phone-call follow-ups.

RESULTS

The median onset time was 15 (10-21) min with lidocaine and 24 (11-37) min with ropivacaine (P=0.109). Spinal lidocaine resulted in a faster resolution of sensory block [148 (130-167) min vs. 188 (146-231) (P=0.022)], unassisted ambulation with crutches [176 (144-208) min vs. 240 (179-302) min (P=0.014)], and voiding [208 (163-254) min vs. 293 (242-343) min (P=0.001)] than ropivacaine. Recovery of motor function required 113 (95-131) min with lidocaine and 135 (87-183) with ropivacaine (P=0.219). Six lidocaine patients reported TNS (40%) as compared with no patient receiving ropivacaine (0%) (P=0.005).

CONCLUSIONS

Spinal block produced with 10 mg ropivacaine 5 mg/ml is as effective as that produced by 50 mg of lidocaine 10 mg/ml. Recovery of unassisted ambulation and spontaneous voiding occurred earlier with lidocaine, but this was associated with a markedly higher incidence of TNS.

Spinal Anesthesia with Lidocaine or Preservative-Free 2-Chlorprocaine for Outpatient Knee Arthroscopy: A Prospective, Randomized, Double-Blind Comparison

BACKGROUND

In this prospective, randomized, double-blind study we tested the hypothesis that 50 mg of 1% preservative-free 2-chloroprocaine would provide a faster resolution of spinal block than the same dose of 1% plain lidocaine.

METHODS

After IV midazolam premedication (0.03 mg/kg), 30 ASA physical status I-II outpatients undergoing knee arthroscopy were randomly allocated to receive 50 mg of either 1% plain lidocaine (n = 15) or 1% preservative-free plain chloroprocaine (n = 15). A blinded observer recorded the evolution of sensory (loss of pinprick sensation) and motor (modified Bromage scale) block until complete regression, as well as times to unassisted ambulation and voiding. A telephone call follow-up was performed 24 h and 7 days after surgery.

RESULTS

Two chloroprocaine patients (13%) and one lidocaine patient (7%) required fentanyl supplementation (100 microg IV) (P = 0.99) intraoperatively, but no patient required general anesthesia to complete surgery. Median (range) times for recovery of sensory and motor function, and unassisted ambulation were faster with 2-chloroprocaine [95 (68-170) min; 60 (45-120) min; and 103 (70-191) min] than lidocaine [120 (80-175) min; 100 (60-140) min; and 152 (100-185) min] (P = 0.019, P = 0.0005, and P = 0.003, respectively). No differences in first voiding were reported between chloroprocaine [180 (100-354) min] and lidocaine patients [190 (148-340) min] (P = 0.191). Transient neurological symptoms were reported in five lidocaine patients (33%) but no chloroprocaine patients (0%) (P = 0.042).

CONCLUSION

Intrathecal injection of 50 mg of preservative-free 2-chloroprocaine 1% resulted in quicker recovery of sensory/motor function, and unassisted ambulation, and fewer incidences of transient neurologic symptoms than the same dose of 1% lidocaine.

Combined Spinal-Epidural Anesthesia in a Dog

OBJECTIVE

To report use of combined spinal epidural anesthesia for tail resection and surgical exploration of the pelvic canal and the perineal-pararectal area in a dog.

ANIMAL

A 4-month-old, 13 kg male Collie dog.

METHODS

Under inhalant anesthesia, an epidural catheter was threaded through a Tuohy needle at L5-L6. Then using a Whitacre spinal needle bupivacaine and fentanyl were administered in the subarachnoid space at L6-L7 level. Fifteen minutes later, morphine was administered epidurally. Bupivacaine and morphine were administered epidurally 4 hours after the subarachnoid injection.

RESULTS

No cardiorespiratory response to surgical stimulation was observed. Postoperative analgesia was satisfactory, and the catheter was removed 30 hours later. No complications or neurologic sequelae occurred before discharge or were noted 10 days later.

CONCLUSION

Combined spinal-epidural anesthesia provided excellent intraoperative anesthesia and perioperative analgesia in a dog undergoing surgery involving the pelvic canal.

CLINICAL RELEVANCE

Combined spinal-epidural anesthesia can be performed in dogs, and its use should be considered in major surgeries caudal to the diaphragm, as the epidural catheter allows cranial extension of the block, providing excellent intraoperative anesthesia and perioperative analgesia.

A prospective, randomized, double-blind comparison of unilateral spinal anesthesia with hyperbaric bupivacaine, ropivacaine, or levobupivacaine for inguinal herniorrhaphy

In 60 patients undergoing inguinal hernia repair, we compared the clinical profile of unilateral spinal anesthesia produced with either 8 mg of hyperbaric bupivacaine 0.5% (n = 20), 8 mg of hyperbaric levobupivacaine 0.5% (n = 20), or 12 mg of hyperbaric ropivacaine 0.5% (n = 20). The study drug was injected slowly through a 25-gauge Whitacre directional needle and patients maintained the lateral decubitus position for 15 min. The onset time and intraoperative efficacy were similar in the three groups. The maximal level of sensory block on the operative and nonoperative sides was T6 (T12-5) and L3 (/[no sensory level detectable]-T4) with bupivacaine, T8 (T12-5) and L3 (/-T3) with levobupivacaine, T5 (T10-2) and T11 (/-T3) with ropivacaine (P = 0.11, P = 0.23, respectively). Complete regression of spinal anesthesia occurred after 166 +/- 42 min with ropivacaine, 210 +/- 63 min with levobupivacaine, and 190 +/- 51 min with bupivacaine (P = 0.03 and P = 0.04, respectively); however, no differences were observed in time for home discharge (329 +/- 89 min with bupivacaine, 261 +/- 112 min with levobupivacaine, and 332 +/- 57 min with ropivacaine [P = 0.28]). We conclude that 8 mg of levobupivacaine or 12 mg of ropivacaine are acceptable alternatives to 8 mg of bupivacaine when limiting spinal block at the operative side for inguinal hernia repair.