The effects of intrathecal fentanyl for spinal anesthesia in lower extremity surgery / 대한마취과학회지

BACKGROUND: Intrathecal opioids in combination with bupivacaine has been shown to provide adequate sensory blockade and early recovery from spinal anesthesia. This study was investigated the added effects of intrathecal fentanyl 10 microgram to bupivacaine for spinal anesthesia. METHODS: Sixty patients undergoing lower extremity surgery were into three groups. Group I received bupivacaine 10 mg (0.5%), gruop II received bupivacaine 5 mg with normal saline 1 ml, and group III received bupivacaine 5 mg with fentanyl 10 microg and normal saline 0.8 ml. RESULTS: There was no significant difference between group I and group III in the peak level and duration of sensory block. But the intensity of motor blockade was decreased in group III compared with group I and side effects of spinal anesthesia with local anesthetics was decreased in group III compared with group I. In Group II, 7 patients were complained the pain during surgery. CONCLUSIONS: Intrathecal fentanyl 10 microgram with bupivacaine 5 mg on spinal blockade provide reliable anesthesia for lower extremity surgery.

The Dose-Dependent Analgesic Effect of Lidocaine for Pain on Injecting Rocuronium / 대한마취과학회지

BACKGROUND: Rocuronium produce intense discomfort on IV injection in conscious patients. The purpose of this study was to evaluate the incidence and severity of pain associated with IV injection of rocuronium in conscious patients and to determine the efficacy of different doses of IV lidocaine at minimizing injection pain. METHODS: The author evaluated 120 in-patients undergoing various elective surgeries. Patients were randomized into four groups of 30 patients for this blind, prospective study. After tourniquet application on the forearm, the patients were given saline (3 ml) (Group I, n = 30), lidocaine 20 mg (Group II, n = 30), lidocaine 40 mg (Group III, n = 30), or lidocaine 60 mg (Group IV, n = 30) diluted in a 3 ml solution. The occlusion was released after 20 seconds and rocuronium 0.6 mg/kg was injected over 10 seconds. The patients were observed and asked immediately if they had pain in the arm; responses were assessed. Five mg/kg of thiopental sodium was injected intravenously, 30 seconds after the administration of rocuronium. RESULTS: The incidence of pain was 86.7% in group I and was significantly lower group II (60.0%), group III (36.3%), and in IV (P <0.05). In addition, patients pretreated with lidocaine were less likely to suffer moderate to severe pain. But, pain incidences and severities were similar in those that received 40 mg or 60 mg of lidocaine. CONCLUSIONS: Lidocaine was effective at relieving rocuronium-induced and doses of 40 mg and 60 mg of lidocaine were most effective.

Extrauterine Incubation of Fetal Goats Applying the Extracorporeal Membrane Oxygenation via Umbilical Artery and Vein

The fetus is an unstable subject for an isolated physiological and biochemical study. To study the fetus in a controlled and stable environment, a trial was done using 12 goat fetuses. Extrauterine incubation system was devised using an extracorporeal membrane oxygenation system. The system consisted of a venous reservoir with a servo-controlled roller pump and a membrane oxygenator. The extra-corporeal circuit and membrane oxygenator were primed with the maternal whole blood of 200 mL. Fetal umbilical cords was exposed by Cesarean section. Fetal umbilical arterial blood was drained via the drainage cannula. The drained blood was perfused to the oxygenator by the roller pump. The highly oxygenated and decarboxylated blood was returned to an umbilical vein via the perfusion catheter. The blood flow rate was controlled manually using a roller pump. Fetal heart rate, blood pressure, and electrocardiogram were continuously recorded. Gas analysis of drained and perfused bood was performed hourly. With this system, the fetuses were able to survive under fairly stable physiological condition for periods of up to 34 hr. The extrauterine incubation system used in this study could therefore be a encouraging future experimental model in researching the artificial placenta for premature fetuses.

Extrauterine Placental Support of Goat Fetuses Using Arteriovenous Bypass / 대한마취과학회지

BACKGROUND: The extrauterine fetal incubation system must meet stable blood gas exchange and sufficient oxygen supply to provide the physiologic oxygen consumption of the fetus. In the fetus, blood gas exchange is totally sustained by the placental circulation. The placenta can be regarded as an extracorporeal organ, and the basic structure of placental circulation comprises arteriovenous (AV) bypass. To mimic this mode of circulation, we used AV ECMO (extracorporeal membrane oxygenation) in the goat fetus, and attempted to achieve stable blood gas exchange and oxygen supply to the fetus. METHODS: Pregnant goats, weighting 30 - 35 kg, were anesthetized with N2O-O2-enflurane. We performed a cesarean section with a midline incision, and cannulated via the umbilical vessels after a hysterotomy, and connected the fetuses to an ECMO circuit. The fetus was transferred to an incubator containing normal saline mixed with antibiotics. Blood samples were obtained every 4 to 6 hours from the circuit for electrolytes, hemoglobin and blood gas analysis and arterial blood pressure and heart rate were monitored through the umbilical artery. Oxygen delivery and consumption were calculated from the measured parameters. Microscopic examinations of the liver, kidney and lung were performed 24 hours after ECMO to know the effect of AV ECMO on the circulation of the organ. RESULTS: AV ECMO was done for 24 hours in the six goat fetuses and the main cause of death was circulatory failure. Heart rates and blood pressure were stable during ECMO. Sodium bicarbonate was injected when mild acidosis occurred and blood gas exchange was maintained stable. Mean pump flow rate was 156 +/- 62 ml/min/kg and oxygen extraction ratio was 30.4%. The liver function tests were sustained within normal limits both before and 24 hours after ECMO, but BUN and creatininincreased beyond upper normal limits 24 hours after ECMO. Microscopic features of the liver and kidney showed congestion 24 hours after ECMO. The fetal lung after 24 hours of ECMO especially showed an increase of mature capillaries in the septum and wall of alveoli compared with the twin fetal lung. CONCLUSIONS: These results indicate that the extrauterine fetal incubation model used for this study was suitable to blood gas exchange and utility of oxygen for goat fetuses.

Partial Airway Obstruction with an Armored Tube by Swelling of the Inner Layer / 대한마취과학회지

An Armored tube is known to be the most effective in maintaining of airway patency during anesthesia in any position. Unfortunately, the tube itself may become the cause of airway obstruction. One of the known complications of the armored tube is a separation of the individual latex layers. This can be caused by herniation into the lumen. Diffusion of nitrous oxide into the inner hernia considerably intensifies the obstruction. The bubbles in the tube wall arise during manufacturing as well as during resterilization. A 62-year-old man with herniation of lumbar disc herniation was intubated with a 8.0 mm armored tube for general anesthesia. 30 minutes later, we experienced signs of partial endotracheal tube obstruction including high arterial PCO2 and inspiratory pressure in prone position. Then, tube suction with catheter was done and signs was slightly improved. But, 90 minutes later, passage of suction catheter was impossible. When operation was finished, patient was turned to supine position. We exchanged the tube with another tube and found inner wall herniation into the armored tube lumen caused by layer separation.

Change of blood gas and hemodynamics in the fetal goat undergoing ECMO through umbilical artery and vein / 대한산부인과학회잡지

OBJECTIVES: The purpose of this study is to establish animal model of extracorporeal membrane oxygenation (ECMO) system that uses membreane type oxygenator and circulation circuit of umbilical artery and vein. Blood gas and hemodynamic changes in the fetal goat undergoing ECMO were also evaluated. METHODS: Total 15 pregnant goat had been used to perform extrauterine fetal incubation using ECMO through umbilical artery and vein. Cesarean-section was performed to pregnant goat (35 kg) of 120-130 days of gestation to insert catheters (8 Fr) into the umbilical artery and vein. The tip of inserted catheter's the other end was connected with the circuit system including membrane type oxygenator (Polystan) and roller pump. A total of 300 ml of blood was drawn from donor nonpregnant goat and primed into circuit on the day of surgery. The goat fetus was immersed in a chamber filled with artificial amniotic fluid to monitor blood flow dynamics and blood gas was analyzed. RESULTS: The ECMO system using umbilical cord in the extrauterine incubation of fetal goat was developed and maximum survival of goat fetus was 34.5 hrs (mean survival was 856.6+/-688 min). Oxygen tension (PO2) in umbilical artery and vein were 20.53+/-2.54 mmHg, 31.03+/-13.03 mmHg and oxygen saturation (SO2) in umbilical artery and vein were 46.61+/-18.14 mmHg, 71.56+/-15.39 mmHg. Mean blood flow was 176+/-62 ml/min/kg. CONCLUSION: We suggest that our experimental model as an extrauterine fetal research could be a reasonable method in future advanced studies. However, longterm survival of extrauterine fetus needs more suitable hemodynamic and blood gas condition supported by further researches.

The Effects of Combined Spinal Epidural Anesthesia for Lower Extremity Surgery / 대한마취과학회지

BACKGROUND: Spinal anesthesia is a simple technique requiring a small dose of local anesthetic to provide intense and reliable block. And epidural anesthesia with the catheter technique gives a better control of the level of analgesia and a good postoperative pain relief using opioids, local anestheties or both. Therefore, the combined spinal epidural (CSE) anesthesia was evaluated to provide rapid onse of action, good muscle relaxation, prolonged duration of the block and postoperative pain relief. METHODS: All patients were placed in a lateral position. Using a midline approach at L interspace, a 18G Tuohy needle was introduced into the epidural space. A 27G Whitacre spinal needle was passed through the Tuohy needle until free flow cerebrospinal fluid, and than 0.5% heavy bupivacaine 3ml(15mg) was injected. The spinal needle was withdrawn and the epidural catheter was inserted. The dermatome level and time of sensory block was evaluated using loss of sensation of pinprick test every 1 minute for 30 minutes, until the maximum sensory block was established. Motor block was assessed using the Bromage scale. And postoperatively we interviewed the patients for opinioes on the blockade and complication. RESULTS: The mean values of maximum sensory block level were T8 (T8.0+/-1.7 dermatome) and at that time was 8min 30sec (8.5+/-1.2min). The motor blockade of lower extremity was Bromage 3 in all patients. Prolonged anesthesia over 2 hours of operation was accomplished by adding 0.5% bupivacaine through epidural catheter. Subjective evaluation by the patients about postoperative pain control was excellent. CONCLUSIONS: CSE anesthesia appears to combine the reliabiIity and rapid onset of spinal block, and the ability to extend the block and postoperative analgesia by using the epidural catheter while minimizing their drawbacks.

The Effects of Epidural Clonidine Added to Bupivacaine , Fentanyl and Epinephrine after Total Abdominal Hysterectomy / 대한마취과학회지

Epidurally administered clonidine, a selective alpha2-adrenergic agonist, has been reported to produce postoperative analgesia. The aim of this study was to see if the addition of a small dose of clonidine to a mixture of bupivacaine, fentanyl and epinephrine prolonged the duration of analgesia and reduce the number of injections or the total bupivacaine requirement and the incidence of side effects. Forty patients presenting for TAH in ASA physical status 1 or 2, were randomly divided into two groups group 1 was given a 10 ml epidural solution of bupivacaine 12.5 mg combined with fentanyl 50 pg and epinephrine 50ug ; group 2 was given the same solution with clonidine 75 ug. Changes in the systolic and diastolic blood pressure and the pulse rate were recorded at 5, 10, 20, 30, 45, 60, 75, 90, 105 and 120 minutes after drug administration, and the analgesic effects were assessed by measuring pain score (Prince Henry Score), analgesic duration, total bupivacaine requirement for 24 hours and side effect. The results were as follows; 1) Heart rate changed little in group 1 and decreased significantly in group 2. 2) Systolic and diastolic blood pressure decreased significantly in all groups (earlier in group 2 than in group 1). 3) The mean duration of analgesia was significantly prolonged in group 2, compared with group 1 (437 min in group 2; 229 min in group 1). For 24 hours after the first injection, numbers of injections (6 in group 1; 3.15 in group 2) and total bupivacaine requirements (75.0 mg in group 1 ; 39.1 mg in group 2) were significantly reduced. 5) The side effects including hypotension, nausea and vomiting, pruritus, and respiratory depression were not significantly different from each other. These results show that epidurally administered clonidine helps to prolong analgesic duration, and decreased need for supplemental bupivacaine, after lower abdominal surgery.

Cardiovascular Changes of Midazolam for Induction of Anesthesia / 대한마취과학회지

The cardiovaseular response evoked by tracheal intubation was observed in 69 patients undergoing elective surgery in whom anesthesia was induced with group A, B and C induction agents. Sixty nine ASA class 1 or 2 surgical patients were divided into three groups. Group A: thiopental 5 mg/kg (control) Group B: thiopental 2 mg/kg with midazolam 0.1 mg/kg Group C: midazolam 0.2 mg/kg Systolic and diastolic blood pressure, mean arterial pressure, heart rate and loss of eyelid reflex were measured in each group. There was a little difference in the cardiovascular changes between group A and C. But there was not a significant difference between group A and B and also between group B and C. The measured time until loss of eyelid reflex of the group C (55+/-30 sec) was considerably longer than other groups (Group A: 10+/-3 sec, Group B: 37+/-13 sec). The incidence of venous complication in three groups was low. Pain on injection and posto- perative nausea and vomiting was noted in one patient of the group A and B respectively, but no patient in the group C. There was no significant difference in the incidence of the postoperative local venous complication. On the whole, these results suggest that the difference between midazolam and thiopental had no apparent hemodynamic change. From the above results, both midazolam alone and midazolam combined with thiopental may be useful agents for induction of anesthesia.

Cardiac Arrest During Pediatric Anesthesia / 대한마취과학회지

It is a well known that cardiac arrest can occur during general anesthesia. We had experienced of a cardiac arrest during anesthsia in a child with halothane just after the use of a thiopental sodium and vecuronium bromide. When the cardiac asystole was noted by E.C.G., immediate treatment was performed. In this case, We think that Cardiac arrest being related to several factors, anxiety about operation, rough sugical maniplation, light anesthesia and drugs.