Effect of intra-articular injection of levobupivacaine on articular cartilage and synovium in rats.

OBJECTIVE: Intra-articular local anesthetics are often used for prevention of pain after arthroscopic knee surgery. However, the effect of local anesthetics other than bupivacaine on articular cartilage and synovium has not been studied. Also, complications associated with the injection of intra-articular bupivacaine have appeared in the literature. The aim of this study was to evaluate the effects of levobupivacaine on the articular cartilage and the synovium in rats. METHODS: Under aseptic conditions 0.25 ml (5 mg/ml) of levobupivacaine was injected into the right knee joint while 0.25 ml of saline was simultaneously injected into the left knee joint of 20 adult Sprague-Dawley rats. The purpose of saline injections was to serve as a control group. Groups of five rats were killed on days 1, 7, 14 and 21 after administration of injections. The knee joint samples were evaluated for the presence of inflammation in the articular and periarticular tissues and the synovium. RESULTS: There were no significant differences between the levobupivacaine and control groups with respect to inflammation in the articular and periarticular tissues and the synovium. CONCLUSIONS: Although more studies are needed before final recommendations can be made, by evaluating the results obtained from this study, the clinical use of intra-articular levobupivacaine can be recommended for arthroscopic knee surgery.

Comparison of Flexiblade and Macintosh laryngoscopes: cervical extension angles during orotracheal intubation.

SUMMARY: The Flexiblade(TM) is a new laryngoscope with a flexible blade, a handle and a lever, allowing gradual flexion over the distal half of the blade. In this study, we aimed to compare cervical vertebral movements during tracheal intubation with the Flexiblade and Macintosh laryngoscope in 32 patients undergoing elective surgery requiring general anaesthesia (n = 16 per group). Fluoroscopic images of cervical movement were captured before, during and after intubation and evaluated by a radiologist. C1-C2 cervical vertebral movement was significantly reduced during the intubation in the Flexiblade group (p < 0.0001). C2-C3 cervical movement was similar in both groups (p = 0.81). No significant differences were noted in success rates for intubation, oxygen saturation levels, haemodynamic variables or intubation-related injury. The decreased extension angle between C1-C2 during Flexiblade laryngoscopy compared with Macintosh laryngoscopy may be an advantage where neurological damage with cervical movement is a concern.

Comparison of two ketamine-propofol dosing regimens for sedation during interventional radiology procedures.

AIM: Invasive diagnostic and therapeutic interventional radiological procedures can be painful and anxiety provoking. The combination of propofol and ketamine may minimize the need for supplemental opioid analgesics and has the potential to provide better sedation with less toxicity than either drug alone. METHODS: Seventy-two consenting ASA physical status I- III patients undergoing interventional radiological procedures under sedation were recruited according to a randomized, double-blind, institutional review board-approved protocol. Patients were randomized to two groups. Group 1 received propofol 0.5 mg.kg-1 + ketamine 0.5 mg.kg-1, and group 2 received propofol 0.5 mg.kg-1 + ketamine 0.25 mg.kg-1 intravenously. RESULTS: There were no significant differences between the two groups with respect to demographic characteristics and the duration of the interventional radiological procedure, hemodynamic data, oxygen saturation, or side-effects. However, the mean propofol dosage was higher in group 2 (33.7+/-39.3 mg) than in group 1 (15.5+/-22.3 mg), and the number of oversedated patients (sedation score >4) was higher in group 2 (19 patients) than group 1 (6 patients) (P=0.019 and P=0.001, respectively). Sixteen patients (44%) in group 1 and 21 (58%) patients in group 2 required additional propofol during the procedure. The mean recovery times were 12.1+/-1 minutes in group 1 and 13.8+/-0.8 minutes in group 2 (P>0.05). CONCLUSION: In conclusion, the two different dosages of ketamine coadministered with propofol for sedation during interventional radiological procedures showed no clinically significant hemodynamic changes or side effects, and both appeared to prompt early recovery time. We recommend propofol 0.5 mg.kg-1 + ketamine 0.5 mg.kg-1 for sedation and analgesia during interventional radiological procedures, rather than propofol 0.5 mg.kg-1 + ketamine 0.25 mg.kg-1 because the former combination is associated with reduced rescue propofol requirements and therefore less oversedation.

Upper cervical vertebrae movement during intubating laryngeal mask, fibreoptic and direct laryngoscopy: a video-fluoroscopic study.

BACKGROUND AND OBJECTIVE: Minimizing cervical vertebrae motion during endotracheal intubation is important in patients with cervical instability. The aim of this study was to compare upper cervical spine extension during endotracheal intubation using three different techniques. METHODS: Duration of intubation and movement of upper cervical vertebrae during endotracheal intubation were compared in 33 patients undergoing lumbar laminectomy. Patients requiring tracheal intubation under general anaesthesia and neuromuscular blockade were randomly allocated into three groups - direct laryngoscopy, intubating laryngeal mask (LM) airway and fibreoptic laryngoscopy. The procedure was recorded by video-fluoroscopy and analysed with computer-assisted measurements. The maximum movement of the C1/C2 and C2/C3 vertebrae during intubation were obtained. Data were analysed using one-way analysis of variance with Bonferroni and Kruskal-Wallis tests. RESULTS: We found statistically significant movement between the first and second, but not between the second and third cervical vertebrae. The mean (+/-SD) movement at C1/C2 was 10.2 +/- 7.3 degrees with direct laryngoscopy, 5.0 +/- 6.3 degrees with LM and 1.6 +/- 3.2 degrees with fibreoptic laryngoscopy. This difference was statistically significant (P = 0.01) between the direct and fibreoptic laryngoscopy groups. The maximum movement at C2/C3 was 2.2 +/- 10.1 degrees with direct laryngoscopy, 3.5 +/- 5.1 degrees with LM and 0.5 +/- 3.2 degrees with fibreoptic laryngoscopy. Duration of intubation was significantly longer in the intubating LM group (P < 0.001). CONCLUSION: We conclude that fibreoptic laryngoscopy is the more suitable intubation technique when cervical spine movement is not desired.