The Effects of Lidocaine with Epinephrine on Bupivacaine-Induced Cardiotoxicity

Evaluation of Targeted Bupivacaine, Bupivacaine-lidocaine-epinephrine, Dexamethasone, and Meloxicam for Reducing Acute Postoperative Pain in Cats Undergoing Routine Ovariohysterectomy

This study compared bupivacaine (BUP), bupivacaine-lidocaine-epinephrine (BLE), dexamethasone (DEX), and meloxicam (MEL) targeted at specific, potentially painful sites for reducing acute postoperative pain in cats undergoing elective ovariohysterectomy. One hundred fifty-one cats were included in a prospective, randomized, double-blinded clinical trial. Anesthesia consisted of a standardized protocol including buprenorphine, ketamine, dexmedetomidine, and isoflurane. A ventral midline ovariohysterectomy was performed, and cats were administered targeted injections of 0.5% bupivacaine (2 mg/kg); a combined 0.25% bupivacaine (1 mg/kg), 1% lidocaine (2 mg/kg), and 1:100,000 epinephrine (0.005 mg/kg); dexamethasone (0.125 mg/kg); or meloxicam (0.2 mg/kg) intraoperatively at the ovarian suspensory ligaments, uterine body, and incisional subcutaneous tissues. A 0-10 Numeric Pain Rating Scale (NRS) was used to assess cats postoperatively, 1 hour and 3 hours after anesthesia recovery prior to a same day discharge. Pain scores among evaluators were in good agreement with an overall Intraclass Correlation Coefficient (ICC) of 0.7897 (95% Confidence Interval 0.795-0.8313).  In all groups, overall pain scores 1-hour post anesthesia recovery were significantly higher than scores 3 hours post anesthesia recovery (P < .0001). Averaged pain scores compared among treatment groups did not differ at 1 hour post recovery. At 3-hours post anesthesia recovery, MEL group cats had significantly lower pain scores than the BLE group (P = .018). Study results indicate that early postoperative pain scores were similar for cats receiving local infiltrations of BUP, BLE, DEX, and MEL as part of a multimodal pain therapy for routine ovariohysterectomies. MEL showed somewhat better results 3 hours post anesthesia recovery, gaining significance over the BLE group.

Efficacy of phentolamine mesylate in reducing the duration of various local anesthetics

Background

To evaluate changes in the effectiveness of phentolamine mesylate in combination with different local anesthetics (LAs) and vasoconstrictors. A prospective randomized double-blind study was conducted with 90 patients divided into three groups, with each group being administered one of three different LAs: lidocaine 2% 1/80,000, articaine 4% 1/200,000, and bupivacaine 0.5% 1/200,000.

Methods

We compared treatments administered to the mandible involving a LA blockade of the inferior alveolar nerve. Results were assessed by evaluating reduction in total duration of anesthesia, self-reported patient comfort using the visual analog pain scale, incidence rates of the most common adverse effects, overall patient satisfaction, and patient feedback.

Results

The differences among the three groups were highly significant (P < 0.001); time under anesthesia was especially reduced for both the lip and tongue with bupivacaine. The following adverse effects were reported: pain at the site of the anesthetic injection (11.1%), headaches (6.7%), tachycardia (1.1%), and heavy bleeding after treatment (3.3%). The patients' feedback and satisfaction ratings were 100% and 98.9%, respectively.

Conclusions

Efficient reversal of LAs is useful in dentistry as it allows patients to return to normal life more readily and avoid common self-injuries sometimes caused by anesthesia. Phentolamine mesylate reduced the duration of anesthesia in the three studied groups, with the highest reduction reported in the bupivacaine group (from 460 min to 230 min for the lip and 270 min for the tongue [P < 0.001]).

Internal fixation of metacarpal fractures using wide awake local anesthesia and no tourniquet

We sought to report on the use of wide-awake local anesthesia and no tourniquet (WALANT) for internal fixation of metacarpal fractures. We retrospectively examined 10 patients with metacarpal fractures that required either closed reduction and internal fixation (CRIF) or open reduction and internal fixation (ORIF). WALANT was administered 20minutes before the surgery outside the operating room. Once the area was numb, an open or closed reduction was made followed by internal fixation of the fracture using plating, intramedullary screws or Kirshner wires (K-wires). We used intraoperative X-ray to confirm anatomic reduction and correct internal fixation. After proper reduction and fixation, the active range of motion (AROM) was assessed while the patient was awake. Patients were discharged the next day after evaluating their neurovascular status and establishing pain control. Follow-up evaluations were carried out at 2, 6 and 12 weeks postoperatively. All individuals underwent uneventful operations. No significant pain or bleeding was recorded during the operation. Nine out of ten patients regained full AROM at the 12-week follow-up visit in the outpatient clinic. One patient still had slight reduction of range of motion (ROM) of the 5th metacarpophalangeal joint. No neurovascular damage or surgical site morbidity was recorded. CRIF and ORIF of simple metacarpal fractures can be executed successfully using WALANT with good functional results without increased morbidity compared to monitored anesthesia care.