Comparison of an intraoperative infusion of dexmedetomidine or fentanyl for the perioperative hemodynamics, achieving hypnosis and sedation, and the postoperative pain control

BACKGROUND: The aim of this study was to compare dexmedetomidine (DEX), which is a selective, short-acting, central alpha2-adrenergic agonist, with fentanyl in terms of the hemodynamic stability, achieving hypnosis and sedation, and the postoperative pain control at the PACU (postanesthetic care unit). METHODS: In this double-blind study, 50 consecutive total laparoscopic hysterectomy patients scheduled for elective surgery were randomly assigned to receive either dexmedetomidine 1 microg/kg over 10 min followed by a 0.5 microg/kg/hr infusion (the DK group) or fentanyl 0.8-1.2 microg/kg over 1 min followed by a 0.2-0.6 microg/kg/hr infusion (the FK group) from the time of ending the operation after total hysterectomy to the time in the PACU. We evaluated the pain VAS scores, the modified OAA/S scores, the BIS, the vital signs, the respiratory variables (SpO2, RR and EtCO2) and the perioperative side effects to compare the efficacy of dexmedetomidine and fentanyl. RESULTS: Compared with the fentanyl-ketorolac (FK) group, the modified OAA/S scores were significantly lower in the dexmedetomine-ketorolac (DK) group at 0, 5 and 10 min after arrival at the PACU (P < 0.05), whereas the pain VAS and BIS were not significantly different between the two groups. The blood pressure and heart rate in the DK group was significantly lower than that of the FK group at the PACU (P < 0.05). CONCLUSIONS: The DK group, at the doses used in this study, has a significant advantage over the FK group in terms of the postoperative hemodynamic stability at the PACU. There was no significant difference between the two groups for the postoperative pain control.

Comparison of an intraoperative infusion of dexmedetomidine or fentanyl for the perioperative hemodynamics, achieving hypnosis and sedation, and the postoperative pain control

BACKGROUND: The aim of this study was to compare dexmedetomidine (DEX), which is a selective, short-acting, central alpha2-adrenergic agonist, with fentanyl in terms of the hemodynamic stability, achieving hypnosis and sedation, and the postoperative pain control at the PACU (postanesthetic care unit). METHODS: In this double-blind study, 50 consecutive total laparoscopic hysterectomy patients scheduled for elective surgery were randomly assigned to receive either dexmedetomidine 1 microg/kg over 10 min followed by a 0.5 microg/kg/hr infusion (the DK group) or fentanyl 0.8-1.2 microg/kg over 1 min followed by a 0.2-0.6 microg/kg/hr infusion (the FK group) from the time of ending the operation after total hysterectomy to the time in the PACU. We evaluated the pain VAS scores, the modified OAA/S scores, the BIS, the vital signs, the respiratory variables (SpO2, RR and EtCO2) and the perioperative side effects to compare the efficacy of dexmedetomidine and fentanyl. RESULTS: Compared with the fentanyl-ketorolac (FK) group, the modified OAA/S scores were significantly lower in the dexmedetomine-ketorolac (DK) group at 0, 5 and 10 min after arrival at the PACU (P < 0.05), whereas the pain VAS and BIS were not significantly different between the two groups. The blood pressure and heart rate in the DK group was significantly lower than that of the FK group at the PACU (P < 0.05). CONCLUSIONS: The DK group, at the doses used in this study, has a significant advantage over the FK group in terms of the postoperative hemodynamic stability at the PACU. There was no significant difference between the two groups for the postoperative pain control.

Does the Stellate Ganglion Block Decrease the Postoperative Sore Throat?

BACKGROUND: Decreased circulation of the tracheal mucosa caused by high intracuff pressure of endotracheal tube is responsible for increased incidence of postoperative sore throat. Stellate ganglion block (SGB) can improve the circulation of head and neck and upper extremities and affects postoperative sore throat. METHODS: Sixty female patients were randomly assigned to get unilateral SGB with 1% lidocaine (group I) or saline (group II). Intracuff pressures of endotracheal tube of all patients were maintained at around 50 mmHg during anesthesia. The frequency of sore throat and hoarseness, the severity of sore throat were estimated at arrival of recovery room and 6, 24, 48 hours after extubation. RESULTS: The incidence of sore throat was significant lower at only 6 hours after extubation in the Group I (P <0.05) than in Group II. There were no significant differences of the incidence of hoarseness or severity of sore throat between two groups. CONCLUSIONS: There was statistical significance of the incidence of postoperative sore throat in the SGB patients at 6 hours after extubation. However it may not be possible to alleviate the severity of sore throat with SGB.

The Insertion of a Nasogastric Tube with a Nasopharyngeal Airway / 대한마취과학회지

BACKGROUND: The insertion of a nasogastric tube can be difficult in an anesthetized patient who has a cuffed endotracheal tube in place. The placement of a silastic nasogastric (NG) tube can lead to nasal bleeding or a submucosal dissection in the posterior pharynx. The aim of this study was to determine if the insertion of a nasogastric tube with a nasophryngeal airway can be made easy. METHODS: Sixty patients were randomly assigned to one of two groups; Group 1 and Group 2. For Group 1, a nasogastric tube was inserted first. If this method was not successful with two consecutive attempts, then a nasogastric tube with a nasopharyngeal airway was inserted and if unsuccessful again with two attempts, then Magill forceps were used under laryngoscopy. For Group 2, a nasogastric tube with a nasopharyngeal airway was inserted first. If this method was not successful with two consecutive attempts, then a nasogastric tube was inserted and if unsuccessful again with two attempts, then Magill forceps were used under laryngoscopy. RESULTS: The success rate of the 1st pass in Group 2 was significantly higher than in Group 1 (P < 0.05). The success rate with the 1st intended method in Group 2 was significantly higher than in Group 1 (P < 0.05). The rate of using Magill forceps was not significantly different between the two groups. CONCLUSIONS: The insertion of a nasogastric tube with a nasopharyngeal airway in anesthetized and intubated patients is effective in increasing success rate of insertion. Nasopharyngeal airway traverses the nasopharynx atraumatically and serves as a conduit for the smaller nasogastric tube.

A Case of Atypical Trigeminal Neuralgia Mistaken as Glossopharyngeal Neuralgia: A case report / 대한마취과학회지

Trigeminal neuralgia (TGN) is a relatively well-known disorder with characteristic brief attacks of shooting pain in the facial regions. Atypical signs like constant pain and/or sensory abnormalities can develop as the disease progresses. Some cases begin with atypical signs and later develop all the hallmarks of TGN. The atypical forms of TGN can be misdiagnosed as other pain disorders. We present a patient with facial pain who demonstrated a transformation in signs of glossopharyngeal neuralgia into typical trigeminal neuralgia. A 71 year-old man was referred for sharp episodic pain in his right side of the face and neck. The pain was mainly in the neck, which was worsened especially by swallowing. The condition was initially diagnosed as a glossopharyngenl neuralgia. While controlling the pain conservatively with a sympathetic blockade, the neck pain disappeared suddenly and lower jaw pain triggered by speaking and chewing became prominent, which are the characteristic signs of trigeminal neuralgia.

The Comparison of Sedation Quality, Side Effects, and Recovery Profiles of Propofol Alone, Propofol-Fentanyl and Porpofol-Ketamine PCS for MAC / 대한마취과학회지

BACKGROUND: Propofol has been the most widely used IV adjuvant during Monitored anesthesia care (MAC), even though it lacksanalgesic properties. This study was designed to compare sedation quality, side effects, and recovery profiles of propofol alone (group P), propofol-fentanyl (group PF) and propofol-ketamine (group PK) using PCS for breast biopsy procedures using local anesthesia. METHODS: Anxiety VAS, pain VAS and digit symbol substitution test (DSST) were measured in 60 excision breast biopsy patients with local anesthesia. Vital signs, respiratory (SpO2, RR, and ETCO2) variables, BIS, and OAA/S scores were recorded. Perioperative side effects (e. g., pain on injection, excessive sedation [OAA/S < 4], hypoventilation [ventilatory frequency 8 bpm], hypotension, dizziness, unpleasant feeling, Nausea) were also noted. RESULTS: There were no differences among the three PCS groups with respect to demographic data (Table 1). A/D ratio in PK group had a significant increase over P group. The incidence of excessive sedation and dizziness were significantly more frequent in the PK group patients (P < 0.05)(Table 1, 2). OAA/S scores were significantly decreased in the PK group during near the end of surgery, whereas BIS scores were only at the end of surgery (P < 0.05)(Fig. 1, 2). During 15 min after arrival at recovery room, significantly less patients in the PK group gave correct responses on the DSST than other groups (P < 0.05)(Fig. 2, 3). CONCLUSIONS: In contrast to past studies of ketamine as an alternative to opioid adjuncts during propofol PCS, it has no more advantage than supplemental fentanyl in terms of sedation level and side effects.

Dose-Related Prolongation of Ropivacaine Epidural Anesthesia by Epidural Ketamine / 대한통증학회지

BACKGROUND: Besides its general anesthetic effect, ketamine interacts with sodium channels in a local anesthetic-like fashion, including the sharing of binding sites with those commonly used by clinical local anesthetics. This study evaluated the dose related effects of ketamine during epidural anesthesia with 0.5% ropivacaine. METHODS: Sixty ASA physical status I-II patients, scheduled for minor elective surgery under epidural anesthesia using 0.5% ropivacaine, were randomly divided into three groups (n = 20 each). The patients initially received either 0.5% ropivacaine (group 1), ketamine (0.1 mg/kg) in addition to the epidural 0.5% ropivacaine (group 2) or ketamine (0.2 mg/kg) in addition to the epidural 0.5% ropivacaine (group 3). The regression of sensory block was assessed by transcutaneous electric stimulation (TES), equivalent to a surgical incision. Motor block was assessed using the Modified Bromage's scale. Episodes of bradycardia, hypotension and sedation were also recorded. RESULTS: There were no significant differences among the three groups in the maximal levels of sensory block or the times taken for these levels to be reached. The mean times for the block to regress to two and four segments below the maximal level were significantly prolonged by epidural ketamine. CONCLUSIONS: Epidural ketamine prolongs the duration of ropivacaine epidural anesthesia. These results suggest that ketamine has local anesthetic-like actions.

Changes in Osteopontin Expression in the Rat Lumbar Spinal Cord Following the Avulsion of Lumbar Nerve Roots / 대한해부학회지

This study investigated the expression of osteopontin (OPN) in rat lumbar spinal cords after lumbar nerve root avulsion, using in situ hybridization histochemistry, immunocytochemistry and western blot analysis. Cells expressing OPN were motoneurons and interneurons in the ventral horn, but no signals were observed in neurons in the dorsal horn of the normal lumbar spinal cord. From day 1 after avulsion injury, OPN mRNA-labeled neurons increased in the ventral horn and the intermediate zone. By day 3, relatively strong OPN mRNA signals were found throughout the gray matter of the injured side of the spinal cord with OPN mRNA-labeled cells scattered in the superficial dorsal horn. By day 7, the labeling patterns for OPN mRNA were similar to those on day 3, but the numbers of OPN mRNA-labeled cells in the ventral horn and the intermediate zone peaked. At this point, these labeled cells were also more densely packed and the intensity of signals was stronger. Interestingly, these labeled cells were neurons, but not glial cells such as astrocytes or microglia. This OPN mRNA-labeled cell profile in the dorsal horn had nearly disappeared by day 14 after avulsion injury, and the labeling pattern became similar to that on day 1. By day 28, after avulsion injury, the numbers of OPN mRNA-labeled cells decreased further below control values. These results suggest that increased expression of OPN in the rat lumbar spinal cord after avulsion injury might play an important role in the pathogenesis of damaged neurons.

The Effects of Thoracic Sympathetic Ganglion Block and Gabapentin in a Patient with Myokymia and Neuropathic Pain after a Thoracotomy / 대한마취과학회지

Myokymia is one of involuntary movement, which is characterized by undulatory muscle spasm, similar to the worm's crawl. Sometimes muscle pain, itchy sensation, dysautonomia and other symptoms are associated with it. Derangement of the peripheral or central nervous system after nerve or tissue damage is suspected as the source of impulse generators causing this symptom. We encountered a patient with neuropathic pain and myokymia after thoracotomy. Although several medications and nerve blocks have been applied, all have failed to provide symptom relief. We experienced improvement of the pain and involuntary movement with a thoracic sympathetic ganglion block and gabapentin.

The Optimal Concentrations of Propofol at Eye Opening and Orientation after Propofol-fentanyl TCI in Koreans / 대한마취과학회지

BACKGROUND: We evaluated the optimal concentrations of eye opening and orientation after propofol- fentanyl TCI by CSDT of the pharmacokinetic model using DiprifusorTM in adults retrospectively. Furthermore, we tried to compare those data with the cases of using propofol TCI alone that had been reported. METHODS: After obtaining informed consent and IRB approval, 124 patients of ASA class I or II scheduled for elective surgery were allocated into 3 groups according to age. Three groups were group 1 (n = 40): 18 - 29 years, group 2 (n = 42): 30 - 39 years, group 3 (n = 42): 40 - 54 years. Propofol infusion was started at a propofol target concentration (CT) of 6 microgram/ml by using DiprifusorTM. Anesthesia was mostly maintained with propofol CT 3.5 microgram/ml and fentanyl CT 1.5 ng/ml using a Stelpump and 67% nitrous oxide in oxygen. We estimated the average concentrations of propofol at eye opening and orientation in each group with DiprifusorTM, and we also evaluated the correlation coefficient. RESULTS: Total requirements of propofol in cases of propofol-fentanyl TCI were decreased by 18-26% than in propofol TCI alone. The average concentrations of propofol at eye opening and orientation after surgery were 1.2 - 1.4 microgram/ml. The times to show eye opening and orientation after surgery from stopping of nitrous oxide and infusion were 10.4 - 14.5 min in the propofol-fentanyl group compared with 7.5 - 11 min using propofol TCI alone. CONCLUSIONS: We concluded that the optimal concentrations of propofol at eye opening and orientation after surgery in cases of combination with fentanyl were 1.2 - 1.4 microgram/ml instead of 1.4 - 1.6 microgram/ml with using propofol alone.

The Effect of Loud Operating Room Noise on BIS during Monitored Anesthesia Care / 대한마취과학회지

BACKGROUND: In a noisy hospital setting, it is not easy to induce hypnosis or sedation calmly. Although the noise stress has been neglected, it seems to disturb a patient's sleep or induction of sedation. Therefore, we tried to evaluate the effects of loud operating room (OR) background noise on bispectral index (BIS) during monitored anesthesia care (MAC) by using an audiometer and BIS monitor. METHODS: Thirty adult patients (ASA class I) were scheduled two times for nasal or dental procedures at an interval of two or three days. In a randomized, cross-over study design, we prospectively compared the BIS values according to the loudness of OR noise in two different depths of sedation during MAC. Propofol target controlled infusion (TCI) was started at a propofol target concentration (CT) 2.0 microgram/ml using a DiprifusorTM with flash mode until a BIS 80 and/or a modified Observer's Assessment of Alertness/Sedation (mOAAS) score of 4 (group 1), and BIS 75 and/or mOAAS score 3 (group 2) was obtained. We evaluated the effect site concentrations and the elapsed time and checked the BIS at 50, 80, 110, and 120 dB of sound pressure level (SPL) in both groups. RESULTS: The BIS at 80, 110 and 120 dB of SPL in group 1 was significantly increased compared to those at 50 dB (P < 0.05). Similarly, the BIS at 110 and 120 dB of SPL in group 1 was significantly increased compared to those at 80 dB (P < 0.05). The patients in their twenties were most susceptible to loud OR noise during sedation. CONCLUSIONS: The loud OR background noise might be possible to interfere with induction of sedation to a degree, which was more noticeable on light to moderate sedation than for deep sedation.

Effect of Continuous Infusion of Low Concentrations of Ketamine on the Bispectral Index and Recovery from Propofol-N2O-O2 Anesthesia / 대한마취과학회지

BACKGROUND: Ketamine as an analgesic adjunct in propofol-based anesthesia has the benefit of potent analgesic action and more stable vital signs due to sympathetic stimulation. However, its impact on the bispectral index and speed of recovery is still controvertial. The aim of this study was to evaluate the effects of continuous infusion of low concentrations of ketamine (0.1 microgram/ml) on the bispectral index and speed of recovery from propofol-N2O-O2 anesthesia. METHODS: Forty ASA I or II adult patients scheduled for elective orthopedic surgery were randomly allocated to one of two groups according to intraoperative ketamine use. In group P, anesthesia was induced and maintained with propofol (Ct: 3 - 6 microgram/ml), 67% nitrous oxide and 33% oxygen and the target concentration of propofol was kept at 4 microgram/ml at least 20 min before the end of propofol infusion. In group P + K, the method of anesthesia was same as in group P, but the low concentration (0.1 microgram/ml) of ketamine was continuously infused until discontinuation of propofol using computer-assisted continuous infusion. Bispectral index, recovery time from anesthesia, current/effect concentration of drugs, vital signs before and at induction, end of drug infusion, eye opening time on verbal command, and orientation time were checked. RESULTS: Changes in vital signs showed no differences between the groups. For bispectral index, there was no difference between groups initially, but it was higher (4 - 8) after the end of drug infusion in group P K than in group P. Also, recovery from anesthesia was delayed significantly in group P + K (P < 0.05). CONCLUSIONS: From these observations, we concluded that the use of low concentrations of ketamine during propofol-N2O-O2 anesthesia increased BIS, delayed eye opening and recovery from anesthesia without any benefit to vital sign stability.

Comparison of Subcutaneous Patient-Controlled Analgesia with Intravascular Patient-Controlled Analgesia Using Morphine / 대한마취과학회지

BACKGROUND: Generally, for patients with cancer, chronic disease, burn injury or pediatric patients to whom oral medication is difficult or whose vessels are fragile, it is difficult to inject analgesics parenterally. To know the effect of subcutaneous infusion which would be directly used by patients themselves or their care givers, we compared subcutaneous patient-controlled analgesia (SQ PCA) with intravenous patient-controlled analgesia (IV PCA) morphine for acute postoperative pain. METHODS: We undertook a study to prospective, randomized, controlled patients (n = 30) undergoing elective total hysterectomy to compare SQ PCA with IV PCA morphine for postoperative pain control. We prepared a 5 mg/ml solution of morphine for the SQ PCA group (n = 15) and a 1 mg/ml solution of morphine for the IV PCA group (n = 15). The regimen of morphine was a basal rate 20 microgram/kg/h, 1 mg bolus, 10 min lockout interval, 1 hour limit of 8 mg. We evaluated the VAS score at rest and at coughing after postoperative 6, 12, 18, 24, 30, 36, 42 and 48 hours, 6 hourly doses of morphine, total requirement of infused morphine for 48 hours and delivery to demand ratio. Side effects and satisfactory score were checked too. RESULTS: The Visual analogue scale (VAS) pain score at rest and with coughing, the 6 hourly doses of morphine, the total requirement of infused morphine for 48 hours, the delivery to demand ratio, side effects and the satisfactory score were not significantly different in the two groups (P<0.05). CONCLUSION: Thus SQ PCA morphine represents a clinically acceptable alternative to IV PCA in the treatment of postoperative pain control.

Anesthetic Management of Laparoscopic Surgery in Infant with Congenital Megacolon: A case report / 대한마취과학회지

Many benefits are reported after laparoscopy. As experience, equipment, and techniques have improved, minimally invasive laparoscopic surgery is being applied to younger children. With the advent of this new surgical approach, specific modifications become necessary in anesthetic techniques. During laparoscopy, the pneumoperitoneum performed by peritoneal insufflation of CO2 may induce intraoperative ventilatory and hemodynamic changes that complicate anesthetic management. We present a case of laparoscopic Duhamel operation in a 10-month-old infant weighing 10 kg. After induction with thiopental sodium and vecuronium, anesthesia was maintained with enflurane and 50% nitrous oxide in oxygen. Rapid hypercarbia developed about 5 minutes after introduction of pneumoperitonium, so we gave intermittent manual hyperventilation to avoid hypercarbia untill we finished the surgery. In children, CO2 absorption may be more efficient due to the physiological properties of the immature peritoneum. The functional residual capacity (FRC) is low in children. During laparoscopy, FRC is decreased further due to a variety of factors. In spite of the changes in FRC, arterial oxygenation has not been shown to deteriorate in normal infants. In our case, the changes in end-tidal CO2 tension (PETCO2) during laparoscopy did not influence the hemodynamic change. But insufflation of CO2 induced a significant increase in PETCO2, and produced a fast reaction time of PETCO2.