Soft catheters reduce the risk of intravascular cannulation during epidural block--a retrospective analysis of 1,117 cases in a medical center.

A wet or bloody tap is an inevitable complication while performing epidural block. The influence of different catheters on the incidence of intravascular cannulation during epidural catheterization has not been reported. We observed an initial, relatively different incidence of intravascular cannulation during the placement of different sorts of epidural catheter; hence, a retrospective review was conducted to explore the possible association. We reviewed 1-year interval anesthetic records of 1117 patients who had undergone epidural anesthesia or received patient-controlled epidural analgesia. Epidural catheter placement was performed by a loss of resistance technique with an 18-G Tuohy needle in lateral position. Patients were divided into two groups according to the different types of epidural catheters used (Perifix One, n=590; Perifix Standard, n=527). Primary outcome measurement was the incidence of intravascular injection. Other analyzed outcomes included dura puncture, failure rate, and low back pain. The incidence of epiduralintravascular cannulation was significantly lower using the Perifix One catheter (1.5%; 9/590) than using the Perifix Standard (4.6%; 24/527), p=0.003. The dura puncture rate did not differ significantly between the Perifix One (1.9%; 11/590) and the Perifix Standard (2.5%; 13/527), p=0.49. Failure rates and low back pain incidence were also comparable between the two groups. Application of the soft epidural catheter (Perifix One) may reduce the incidence of epidural intravascular cannulation. We suggest the use of Perifix One catheter instead of Perifix Standard catheter in daily practice.

Electromyographic study of differential sensitivity to succinylcholine of the diaphragm, laryngeal and somatic muscles: a swine model.

Neuromuscular blocking agents (NMBAs) might diminish the electromyography signal of the vocalis muscles during intraoperative neuromonitoring of the recurrent laryngeal nerve. The aim of this study was to compare differential sensitivity of different muscles to succinylcholine in a swine model, and to realize the influence of NMBAs on neuromonitoring. Six male Duroc-Landrace piglets were anesthetized with thiamylal and underwent tracheal intubation without the use of an NMBA. The left recurrent laryngeal nerve, the spinal accessory nerve, the right phrenic nerve and the brachial plexus were stimulated. Evoked potentials (electromyography signal) of four muscle groups were elicited from needle electrodes before and after intravenous succinylcholine bolus (1.0 mg/kg). Recorded muscles included the vocalis muscles, trapezius muscle, diaphragm and triceps brachii muscles. The onset time and 80% recovery of control response were recorded and analyzed. The testing was repeated after 30 minutes. The onset time of neuromuscular blocking for the vocalis muscles, trapezius muscle, diaphragm and triceps brachii muscle was 36.3 ± 6.3 seconds, 38.8 ± 14.9 seconds, 52.5 ± 9.7 seconds and 45.0 ± 8.2 seconds during the first test; and 49.3 ± 10.8 seconds, 40.0 ± 12.2 seconds, 47.5 ± 11.9 seconds and 41.3 ± 10.1 seconds during the second test. The 80% recovery of the control response for each muscle was 18.3 ± 2.7 minutes, 16.5±6.9 minutes, 8.1±2.5 minutes and 14.8±2.9 minutes during the first test; and 21.5±3.8 minutes, 12.5 ± 4.3 minutes, 10.5 ± 3.1 minutes and 16.4 ± 4.2 minutes during the second test. The sensitivity of the muscles to succinylcholine, ranked in order, was: the vocalis muscles, the triceps brachii muscle, the trapezius muscle and the diaphragm. We demonstrated a useful and reliable animal model to investigate the effects of NMBAs on intraoperative neuromonitoring. Extrapolation of these data to humans should be done with caution.

Continuous infraclavicular block for forearm amputation after being bitten by a saltwater crocodile (Crocodylus porosus): a case report.

Two important issues after a complete right forearm amputation are replantation and ongoing pain management. There are no reports of successful forearm replantation as a consequence of a crocodile bite. Here, we discuss our pain management in a case of complete forearm amputation after a bite from a saltwater crocodile (Crocodylus porosus), which necessitated six further operations to achieve successful replantation. Continuous infraclavicular brachial plexus block was effective for acute pain control in this case. We strongly recommend performing the block with an indwelling catheter under ultrasound guidance for higher accuracy and safety.