Young Ryong Choi

Comparison of effects of intraoperative esmolol and ketamine infusion on acute postoperative pain after remifentanil-based anesthesia in patients undergoing laparoscopic cholecystectomy

Background Remifentanil is a short-acting drug with a rapid onset that is useful in general anesthesia. Recently, however, it has been suggested that the use of opioids during surgery may cause opioid-induced hyperalgesia (OIH). Researchers have recently reported that esmolol, an ultra-short-acing β1 receptor antagonist, reduces the postoperative requirement for morphine and provides more effective analgesia than the administration of remifentanil and ketamine. Hence, this study was conducted to determine whether esmolol reduces early postoperative pain in patients who are continuously infused with remifentanil for anesthesia during laparoscopic cholecystectomy. Methods Sixty patients scheduled to undergo laparoscopic cholecystectomy were randomly divided into three groups. Anesthesia was maintained with sevoflurane and 4 ng/ml (target-controlled infusion) of remifentanil in all patients. Esmolol (0.5 mg/kg) was injected and followed with a continuous dosage of 10 µg/kg/min in the esmolol group (n = 20). Ketamine (0.3 mg/kg) was injected and followed with a continuous dosage of 3 µg/kg/min in the ketamine group (n = 20), while the control group was injected and infused with an equal amount of normal saline. Postoperative pain score (visual analog scale [VAS]) and analgesic requirements were compared for the first 6 hours of the postoperative period. Results The pain score (VAS) and fentanyl requirement for 15 minutes after surgery were lower in the esmolol and ketamine groups compared with the control group (P < 0.05). There were no differences between the esmolol and ketamine groups. Conclusions Intraoperative esmolol infusion during laparoscopic cholecystectomy reduced opioid requirement and pain score (VAS) during the early postoperative period after remifentanil-based anesthesia.

The effects of intravenous dexmedetomidine on spinal anesthesia: comparision of different dose of dexmedetomidine

Background In this prospective, randomized, double-blind, placebo-controlled trial, we tried to find out appropriate amounts of single-dose dexmedetomidine to prolong the duration of spinal anesthesia in a clinical setting. Methods Sixty patients who were scheduled for unilateral lower limb surgery under spinal anesthesia were randomized into three groups receiving normal saline (control group, n = 20) or 0.5 or 1.0 ug/kg dexmedetomidine (D-0.5 group, n = 20; D-1, n = 20) intravenously prior to spinal anesthesia with 12 mg of bupivacaine. The two-dermatome pinprick sensory regression time, duration of the motor block, Ramsay sedation score (RSS), and side effects of dexmedetomidine were assessed. Results The two-dermatome pinprick sensory regression time (57.6 ± 23.2 vs 86.5 ± 24.3 vs 92.5 ± 30.7, P = 0.0002) and duration of the motor block (98.8 ± 34.1 vs 132.9 ± 43.4 vs 130.4 ± 50.4, P = 0.0261) were significantly increased in the D-0.5 and D-1 groups than in the control group. The RSS were significantly higher in the D-0.5 and D-1 groups than in the control group. However, there were no patients with oxygen desaturation in dexmedetomidine groups. The incidences of hypotension and bradycardia showed no differences among the three groups. Conclusions Both 0.5 and 1.0 ug/kg of dexmedetomidine administered as isolated boluses in the absence of maintenance infusions prolonged the duration of spinal anesthesia.

Comparison of loss of resistance technique between Epidrum® and conventional method for identifying the epidural space

Background Epidrum® is a recently developed, air operated, loss of resistance (LOR) device for identifying the epidural space. We investigated the usefulness of Epidrum® by comparing it with the conventional LOR technique for identifying the epidural space. Methods One hundred eight American Society of Anesthesiologists (ASA) physical status I or II patients between the ages of 17 and 68 years old and who were scheduled for elective surgery under combined spinal-epidural anesthesia were enrolled in this study. The patients were randomized into two groups: one group received epidural anesthesia by the conventional LOR technique (C group) and the second group received epidural anesthesia using Epidrum® (ED group). While performing epidural anesthesia, the values of variables were recorded, including the number of failures, more than 2 attempts, the incidence of dural puncture, the time needed to locate the epidural space, the distance from the skin to the epidural space and ease of performance, and the satisfaction scores. Results The ED group showed a lower failure rate, fewer cases of more than 2 attempts, a lesser time to identify the epidural space, and better ease and satisfaction scores of procedure than the C group, with statistical significance. Conclusions Using Epidrum® compared to the conventional LOR technique is an easy, rapid, and reliable method for identifying the epidural space.

Left mainstem bronchial rupture during one-lung ventilation with Robertshaw double lumen endobronchial tube -A case report-.

Lung separation using a double-lumen endobronchial tube is necessary for video assisted thoracoscopy (VATs). Bronchial rupture after intubation with a double-lumen endobronchial tube has been rarely reported. We report a case of a 70-year-old man who had solitary pulmonary nodule in his right upper lobe. He was intubated with a left-sided Robertshaw double-lumen endobronchial tube. He underwent a VATs right upper lobectomy with the one-lung ventilation of left lung. During the operation, the rupture of the left mainstem bronchus was detected. Immediately, the thoracotomy was performed and the ruptured left mainstem bronchus was repaired with absorbable sutures (vicryl). Seven days later he had a bronchoscopy to examine the left mainstem bronchus. There was no evidence of the bleeding, leakage and inflammation. Subsequent course was uneventful. Tracheobronchial injuries related to the double-lumen endobronchial tube are discussed.

Anesthetic experience using total intravenous anesthesia in a patient with Isaacs' syndrome -A case report-

We report on an anesthetic experience with a 74-year-old female with Isaacs syndrome, who underwent elective surgery for open rotator cuff repair. Isaacs syndrome is a rare peripheral motor neuron disorder with clinical manifestations such as involuntary muscle twitching, cramps, mild weakness and increased sweating. To avoid prolonged neuromuscular blockade, the patient was observed with neuromuscular monitoring during total intravenous anesthesia with propofol, remifentanil, and atracurium. No adverse events were observed during the anesthetic management, and the patient recovered smoothly from the neuromuscular blockade. We describe the clinical characteristics of Isaacs syndrome and its specific considerations in anesthesia.

Motor Weakness after Caudal Epidural Injection Using the Air-acceptance Test

Air injected into the epidural space may spread along the nerves of the paravertebral space. Depending on the location of the air, neurologic complications such as multiradicular syndrome, lumbar root compression, and even paraplegia may occur. However, cases of motor weakness caused by air bubbles after caudal epidural injection are rare. A 44-year-old female patient received a caudal epidural injection after an air-acceptance test. Four hours later, she complained of motor weakness in the right lower extremity and numbness of the S1 dermatome. Magnetic resonance imaging showed no anomalies other than an air bubble measuring 13 mm in length and 0.337 ml in volume positioned near the right S1 root. Her symptoms completely regressed within 48 hours.

Effect of warmed ropivacaine solution on onset and duration of axillary block

Background Bicarbonate, as an adjunct increasing the non-ionized form of local anesthetics, can reduce latency and prolong duration of regional nerve block. Warming of local anesthetics decreases pKa and also increases the non-ionized form of local anesthetics. We warmed ropivacaine to body temperature (37℃) and evaluated the sensory block onset time, motor block onset time and analgesic duration of axillary block. Methods Patients were consecutively allocated to two groups of 22 patients each. Ropivacaine 150 mg (30 ml) at 20℃ (room temperature) and 150 mg (30 ml) at 37℃ (body temperature) was injected in group 1 and group 2, respectively. Sensory block and motor block was assessed every 5 minutes, for 30 minutes after injection. The duration of analgesia was recorded after operation. Results In group 2, the onset times of both sensory and motor block of the radial, ulnar, median and musculocutaneous nerves were significantly reduced, compared to group 1. Also, the number of blocked nerves was increased in group 2, within 30 minutes after injection. Analgesia lasted for 2 hours longer in group 2, compared to group 1, but the difference was not statistically significant (P > 0.05). Conclusions Warming of ropivacaine to 37℃ can reduce the onset time of both sensory and motor block, during axillary block.

Comparison of spread of subarachnoid sensory block and incidence of hypotension in early and late second trimester of pregnancy

Background Obstetric or non-obstetric surgery can be performed in pregnant women during the second trimester. We evaluated maximal sensory block level (MSBL), and other sensory block characteristics after spinal anesthesia in early and late second trimester pregnant women. Methods Forty-four pregnant women scheduled for cervical cerclage under spinal anesthesia in the early second trimester (Group E) or in the late second trimester (Group L) were enrolled in this study. Spinal anesthesia was performed at the L3/4 and 7 mg of 0.5% hyperbaric bupivacaine was injected into the subarachnoid space. Hemodynamic variables, incidence of nausea/vomiting, ephedrine dose, and sensory block were recorded every 2.5 min during the first 15 min and 20 min after the injection. The MSBL, the time at which MSBL was achieved, and the time to the two-segment regression of the sensory level were also recorded. Results The maximum number of segments blocked was significantly greater in the Group L than in the Group E. The incidence of nausea/vomiting and hypotension, and dose of administrated ephedrine were significantly higher in the Group L than in the Group E. The mean arterial pressure during the 15 min after subarachnoid injection was significantly lower compared to the baseline value in the Group L. Conclusions The MSBL of spinal anesthesia with hyperbaric bupivacaine 7 mg were T9 in the early and T5 in the late second trimester groups. Pregnant women in the late second trimester exhibited increased incidence of hypotension and need for ephedrine than women in the early second trimester.

Head Elevation in Spinal-Epidural Anesthesia Provides Improved Hemodynamics and Appropriate Sensory Block Height at Caesarean Section.

Purpose We aimed to determine whether head elevation during combined spinal-epidural anesthesia (CSE) and Caesarean section provided improved hemodynamics and appropriate sensory block height. Materials and Methods Forty-four parous women undergoing CSE for elective Caesarean section were randomly assigned to one of two groups: right lateral (group L) or right lateral and head elevated (group HE) position, for insertion of the block. Patients were positioned in the supine wedged position (group L) or the left lateral and head elevated position (group HE) until a block height of T5 to light touch was reached. Group HE was then turned to the supine wedged position with maintenance of head elevation until the end of surgery. Hemodynamics, including the incidence of hypotension, ephedrine dose required, and characteristics of the sensory blocks were analyzed. Results The incidence of hypotension (16 versus 7, p=0.0035) and the required dose of ephedrine [24 (0-40) versus 0 (0-20), p<0.0001] were greater in group L compared to group HE. In group L, the time to achieve maximal sensory block level (MSBL) was shorter (11.8±5.4 min versus 20.1±6.3 min, p<0.0001) and MSBL was also higher than in group HE [14 (T2) versus 12 (T4), p=0.0015]. Conclusion Head elevation during CSE and Caesarean section is superior to positioning without head elevation in the lateral to supine position, as it is associated with a more gradual onset, appropriate block height, and improved hemodynamics.

Comparison of rocuronium-induced neuromuscular blockade in second trimester pregnant women and non-pregnant women

BACKGROUNDnThis study set out to compare the onset and duration of rocuronium-induced neuromuscular blockade in second trimester pregnant women and non-pregnant women receiving general anesthesia.nnnMETHODSnForty-seven pregnant (Group P) and forty-seven non-pregnant (Group C) women were enrolled. Anesthesia was induced with propofol 2.0u202fmg/kg and rocuronium 0.6u202fmg/kg, and neuromuscular blockade was assessed with an accelerometric sensor using train-of-four stimulation (TOF-Watch® SX). Tracheal intubation was performed at maximum depression of the first twitch (T1) and anesthesia was maintained with sevoflurane 1.5-2.5% and 50% oxygen in air. We recorded the times to maximum T1 depression and 5% and 25% T1 recovery, as well as the mean arterial pressure and heart rate at baseline, injection of rocuronium, intubation, and 5% and 25% T1 recovery.nnnRESULTSnThe onset of rocuronium-induced neuromuscular blockade (time to maximum T1 depression) did not differ significantly between the groups. The duration (time to 25% T1 recovery) was significantly longer in Group P than in Group C (45.7u202f±u202f12.9u202fmin vs 40.6u202f±u202f10.4u202fmin, Pu202f<0.037). During the recovery period from the blockade, the mean arterial pressure was significantly lower in Group P than in Group C.nnnCONCLUSIONnOur data showed that the rocuronium-induced neuromuscular blockade did not significantly differ in onset but lasted significantly longer in second trimester pregnant women compared with non-pregnant women.