The cardioprotective effect of microemulsion propofol against ischemia and reperfusion injury in isolated rat heart / 대한마취과학회지

BACKGROUND: Lipid-emulsion propofol (LP) has cardioprotective effects against ischemia-reperfusion injury, but it has lipid-related side effects. Microemulsion propofol (MP) is a lipid-free propofol emulsified with 10% purified poloxamer 188 (PP188). PP188 is a nonionic surfactant and has cardioprotective effects. However, some reports have suggested that reduced cardioprotective effects were observed when the cardioprotective agents were used in combination even though each cardioprotective agent has cardioprotective effects. The aims of this study were to examine and compare the cardioprotective effects of MP and LP. METHODS: 50 isolated rat hearts were perfused with modified Kreb's solution. They were divided into 4 groups and underwent 30 minutes of ischemia and 60 minutes of reperfusion. Control group: ischemia-reperfusion was performed without treatment. LP, MP and PP groups: LP, MP and PP188 were infused during the pre-ischemic and reperfusion period, respectively. Hemodynamic parameters and coronary effluent flow rate (CEFR) were measured. Infarct size was determined using triphenyl-tetrazolium staining. RESULTS: In the MP group, systolic pressure was maintained near baseline, the systolic pressure was higher than that in the other groups and HR was lower than that in the other groups during reperfusion. Diastolic pressure was transiently increased in the PP group after treatment and at 5 minutes after reperfusion compared with that in the control group and in the the LP group. There were no differences in dP/dtmax and CEFR between groups. Infarct size in the LP, MP and PP groups was smaller than that in the control group, but there were no significant differences between these three groups. CONCLUSIONS: MP has cardioprotective effects similar to those of LP. MP can be used for cardiac anesthesia in cases with ischemia-reperfusion injury to avoid the lipid-related side effects of LP.

Effect of Intrathecal Morphine for Total Knee Replacement Arthroplasty Elderly Patients / 대한마취과학회지

BACKGROUND: Low-dose intrathecal opioid has been used for early postoperative pain co1ntrol. This study was designed to assess effect intrathecal morphine on postoperative pain control for total knee arthroplasty (TKA) under combined spinal-epidural analgesia (CSE) in elderly patients. METHODS: Fifty four patients over 60 years, undergoing TKA were randomly allocated to three groups. M(0) group for control group did not received intrathecal morphine, M(50) and M(100) group received intrathecal morphine 50microgram and 100microgram respectively. The pain scores (verbal numeric rating scale, VNRS) at rest and coughing, analgesic consumption, patient satisfaction and side effects such as nausea, vomiting, pruritus, headache, dizziness, sedation, respiratory depression, and urinary retention were recorded immediately before and at 1, 3, 6, 12, 24, 48 hour after the initiation of patient-controlled epidural analgesia (PCEA). RESULTS: VNRS were low at each time, and were not exceeding 2 in all groups. M(50) and M(100) group revealed significantly less analgesic consumption compared to M(0) group (P < 0.05). PCEA first injection time after PCEA connection was shortest in M(0) group compared to M(50) and M(100) group. The incidence of pruritus increased in M(50) and M(100) group with dose-dependence, but no significant differences were noticed in other side effects. CONCLUSIONS: Intrathecal morphine use showed no significant analgesic effect except pruritus compared to control group. Further studies are required into the effective intrathecal morphine without side effects in elderly patients for TKA.

Optimal Priming Dose of Rocuronium for Prevention of Succinylcholine Induced Fasciculations

BACKGROUND: Subparalyzing dose of nondepolarizing muscle relaxants is often given prior to succinylcholine to reduce its adverse effects. At the same time, priming dose may worsen the intubating condition due to its antagonizing effect at neuromuscular junction. Although optimal priming dose of rocuronium is known to 0.03-0.04 mg/kg but higher priming dose may reduce interval from priming drug to succinylcholine. This study was designed to determine the maximal priming dose of rocuronium. METHODS: Sixty ASA I or II adult patients were randomized into three groups: group R1 received 0.06 mg/kg of rocuronium, group R2, 0.09 mg/kg and group Scc, normal saline. About 3 minutes after priming dose, thiopental 4 mg/kg, fentanyl 1microg/kg and succinylcholine 2 mg/kg were administered for anesthesia induction. The presence and severity of fasciculations and intubating conditions were evaluated with the incidence of side effects. RESULTS: In preventing fasciculations, group R1 and R2 were significantly better than group Scc, without significant difference between group R1 and R2. Intubation conditions were significantly worse in group R2 than in group Scc. CONCLUSIONS: The maximal priming dose of rocuronium to prevent fasciculations and optimizing intubating condition was 0.06 mg/kg.

Comparison of Laryngeal Tube Insertion Condition according to Effect-Site Concentration during Target-Controlled Infusion (TCI) of Propofol / 대한마취과학회지

BACKGROUND: The aim of the study was to compare the laryngeal tube (LT) insertion conditions at 3.0 and 3.5microgram/ml effect site concentrations (ECs) during anesthesia induction using the target-controlled infusion (TCI) of propofol. METHODS: The forty patients were randomly divided into two groups. The patients received TCI of propofol with a 6.0 microgram/ml target plasma concentration (Cpt) and then an LT was inserted without the aid of a muscle relaxant when the predicted EC reached 3.0microgram/ml (group 1) or 3.5microgram/ml (group 2). The conditions of LT insertion, i.e., mouth opening, gagging, coughing, head or limb movement, laryngospasm, and overall ease, and hemodynamic responses were evaluated 3 min after midazolam injection, at loss of consciousness and eyelash reflex, and immediately before, immediately after, 1 min after, and 3 min after LT insertion. We also compared times required to insert LTs, cuff volumes, and incidences of blood staining and of postoperative sore throat. RESULTS: The conditions of LT insertion, except laryngospasm and overall ease, were not significantly different in the two groups. The incidence of laryngospasm in group 1 (25%) was significantly higher than in group 2 (0%) and group 2 was better than group 1 in terms of overall ease of insertion (P<0.05). No significant differences were observed between the two groups in terms of hemodynamic responses. Minimum cuff volume to 60 cmH2O was 64.0 +/- 8.3 ml in Group 1 and 63.9 +/- 6.5 ml in Group 2, and time required for LT insertion was 21.0 +/- 11.0 sec in Group 1 and 24.7 +/- 16.6 sec in Group 2. Postoperative sore throat and blood stain incidences were not significantly different in the two groups. CONCLUSIONS: After induction with 6microgram/ml of Cpt using propofol TCI for LT insertion, LT insertion at 3.5microgram/ml of EC provided a lower incidence of laryngospasm and better overall ease than insertion at 3.0microgram/ml of EC.