Anesthetic management for a patient with severe mento-sternal contracture: difficult airway and scarce venous access: A case report / 대한마취과학회지

There are many problems in the anesthetic management of patients with scar contracture. In this case, a 41-year-old male with severe scar contracture on his face, neck, anterior chest, and both shoulders underwent surgery for resurfacing with flaps. We tried to awake fiberoptic orotracheal intubation with GlideScope(R) Video laryngoscope guide after surgical release of contracture under local anesthesia. We report a successful management of a patient with severe burn contracture achieved by combined effort of surgeons and anesthesiologists.

Damage to the cuff of EMG tube at endotracheal intubation by using a lightwand: A case report / 대한마취과학회지

Electromyogpraphic endotracheal tube (EMG tube) is a new device used to monitor recurrent laryngeal nerve integrity during thyroid surgery. The EMG tube has 2 pairs of electrodes on the surface of silicon-based tube reached to inner space of tube cuff. We experienced an unusual endotracheal tube-related problem from the distinct structural feature of the EMG tube. In this case, we intubated a patient who had difficult airway with the EMG tube using a lightwand. After successful endotracheal intubation, we could not expand the pilot balloon and ventilate the patient effectively. We removed the EMG tube and found that one of electrodes of the EMG tube is bended and made a right angle with the long axis of the tube, and perforated the tube cuff. So we report this case to make anesthesia providers aware that much more attention is needed to use EMG tube during endotracheal intubation.

Growth Suppression of Leukemic Cells by Hyperbaric Nitrous Oxide and Methotrexate / 대한마취과학회지

BACKGROUND: Nitrous oxide inactivates cobalamin which is important in the folate-dependent synthesis of thymidylate. Also, methotrexate has the anti-cancer activity. The aim of this work was to determine the optimal pressure and exposure time of nitrous oxide that maximize the suppression of cancer growth, and the adequate level of methotrexate that maximize the anti-cancer activity of nitrous oxide. METHODS: Acute lymphoblastic leukemic cells and normal lymphocytes were cultured in hyperbaric chamber at 1, 2 and 3 atm of 74% nitrous oxide in 24, 48 and 72 hours at 0, 0.3, 0.5 and 0.7 micrometer of methotrexate, respectively. The results were expressed in the ratio of cell number in hyperbaric chamber to that in the incubator. RESULTS: Compared to control, the growth rates of cancer cells and lymphocytes were 0.767, 0.990 at 1 atm, 0.592, 0.880 at 2 atm and 0.718, 0.864 at 3 atm of nitrous oxide in 24 hours. The survival fraction of cancer cells and lymphocytes were 0.767, 0.894 in 24 hours, 0.800, 0.630 in 48 hours, and 0.571, 0.597 in 72 hours, at 1 atm of nitrous oxide. The growth rates of cancer cells and lymphocytes were 1.012, 0.745 at 0 micrometer, 0.912, 0.696 at 0.3 micrometer, 0.77, 0.647 at 0.5 micrometer and 1.133, 0.506 at 0.7 micrometer of methotrexate. CONCLUSIONS: The pressure increase of nitrous oxide significantly suppressed the growth of lymphocyte but not cancer cells. However, growth of cancer cells and lymphocytes were significantly reduced at high concentration of methotrexate and larger exposure time.

A Statistical Analysis of Preanesthetic Consultation in the Pediatric Patient / 대한마취과학회지

BACKGROUND: Adequate pre-anesthetic evaluation could improve both patient outcome and hospital management by reducing the rates of operation delay and cancellation. We undertook this study to contribute to the establishment of a pre-anesthetic evaluation system by studying pediatric patients who had preoperatively consulted the anesthesiology department. METHODS: Data were collected using the EMR (Electronic Medical Record) system. 260 pediatric patients, age limitation 15 years, who had consulted our anesthesiology staff, were enrolled. The age distributions, departments consulted and clinical causes were analyzed. RESULTS: The age distributions were as follow; <1 month: 1.5%, 1 month-1 year: 29.2%, 1-4 years: 23.8%, 5-7 years: 18.1% and 8-15 years: 27.3%. The causes of the consultations were mainly pulmonary (27.3%), cardiovascular (21.9%), gastrointestinal (12.3%), airway (9.6%) problems and other causes (26.5%). The most common diseases were congenital heart disease, prematurity and URI. The major departments consulted were general surgery (16.2%), ophthalmology (15.4%), thoracic surgery (15.0%), plastic surgery (15.0%) and orthopedic surgery (14.6%). CONCLUSIONS: The establishment of a communication system with surgeons concerning patient management guidelines about the common causes of consultations would improve hospital management by reducing the incidences of delay and the cancellation of operations.

Comparison of CVP Measurements in the Intrathoracic and the Intraabdominal Vena Cava in Pediatric Cardiac Surgical Patients / 대한마취과학회지

BACKGROUND: Although concerns exist as to the safety of placing central venous catheters via the internal jugular or subclavian veins, central venous catheterization is often performed in pediatric patients undergoing cardiac surgery and cardiopulmonary bypass. We hypothesized that central venous pressures (CVP) measured in the inferior vena cava by the femoral venous approach accurately reflect those in the superior vena cava. METHODS: We simultaneously measured CVP at the superior vena cava and at the abdominal vena cava or common iliac vein in 56 children scheduled for cardiac surgery. A total of 133 data pairs were collected. A single lumen, femoral catheter and an intrathoracic catheter, according to patient weight were placed intraoperatively in all patients. RESULTS: The ages of the patients ranged from 5 days to 84 months (mean 13.1 months), and heights from 44 to 111 cm (mean 71.8 cm). Measurements of the central venous pressure in the inferior vena cava and in the superior vena cava correlated well (r = 0.93 for spontaneous ventilation, r = 0.85 for mechanical ventilation with a closed sternum, r = 0.69 for mechanical ventilation with an open sternum). CONCLUSIONS: We conclude that while central venous pressures measured in the inferior and superior vena cava are not statistically identical, that differences between the two are well within clinically acceptable limits.

Home Mechanical Ventilation of Pediatric Patients / 대한마취과학회지

BACKGROUND: In the past patients who needed ventilatory care were treated in the hospital but now, thanks to advanced technology, those patients can be treated at their homes. This study was done to evaluate the clinical course of each patient and the effectiveness of home ventilatory care program. METHODS: We reviewed ten cases of ventilator - dependent children who were discharged from the pediatric intensive care unit since we started a home ventilatory care program. RESULTS: Six patients remained ventilator - dependent, three patients died and one patient cannot be reached. The clinical courses before home ventilatory care was decided were diverse. None of the patients needed hospital care related to complications of mechanical ventilatory care. CONCLUSIONS: Despite the small number of patients and the short follow up duration, we concluded that ventilator-dependent children can be successfully managed at their homes.

Selection Criteria of Laryngeal Mask Airway Size in Infants and Children: Comparison between Body Weight and Age / 대한마취과학회지

BACKGROUND: In children, laryngeal mask airways (LMA) almost always show a tendency to come out of the mouth too much before and during inflating the cuff. We hypothesized that the selection criteria based on body weight seemed to be set too low or inappropriate in children. METHODS: After IRB approval and informed consent from parents, pediatric patients (n = 63; 42 male, 21 female) weighing less than 20 kg, of ASA physical status 1 or 2, and in whom the use of an LMA was not contraindicated, were studied. LMAs were inserted by an experienced investigator and connected to a volume ventilator, and positive pressure ventilation was initiated. Inspiratory and expiratory tidal volume (V(T)) were measured to calculate the fraction of leakage (F(L), %) as ([inspiratory V(T)-expiratory V(T)]/inspiratory V(T)) 100. The larynx was inspected with a fiberoscope (FOB) located just proximal to the aperture bar. For each size of LMA, we divided each group into two subgroups depending on the body weight (4, 7 or 12 kg) and age (2, 9 or 30 months) and compared the FOB finding and F(L) between the two subgroups. In the other 16 patients, LMAs of two different sizes were applied successively to a patient, and its FOB grades were compared. RESULTS: For size 1 LMAs (n = 22), the FOB finding and F(L) were not different between the subgroups. For size 1.5 LMAs (n = 20), patients weighing 7 to 10 kg or aged 9 months. For size 2 LMAs (n = 21), FL was correlated with body weight (P < 0.001, r(2) = 0.448) and age (P < 0.001, r(2) = 0.424). In 8 patients of 5 to 7 kg, use of size 1 LMAs had a better FOB grade than that of size 1.5 LMAs (P = 0.031). In the other 8 patients of 10 to 12 kg, there was no difference of FOB grades between the size 1.5 and 2 LMAs. CONCLUSIONS: For patients weighing 5 to 7 kg, the use of size 1 LMAs is recommended. Contrary to adults, a smaller LMA may have to be tried if an LMA size turns out to be inappropriate.

An Analysis of Overtransfusion in Total Hip Replacement Surgery / 대한마취과학회지

BACKGROUND: This study was designed to identify overtransfusion- triggering clinical factors in patients undergoing total hip replacement surgery. METHODS: The discharge hematocrit was chosen for evaluation. Estimated red cell loss for each patient during the admission was calculated by the differences between admission and discharge hematocrit, multiplied by patient whole blood volume. Total RBC lost was then determined by the sum of RBC volume lost plus the RBC volume transfused. RBC transfusion was considered appropriate if given to replace RBC volume lost in excess of 15% of the RBC volume in each patient at admission. Comparison of transfusion practice was done on the basis of sex, age, preoperative hematocrit, surgical procedure and anesthetic method. RESULTS: Forty-six (37.7%) of 122 patients were identified to have been transfused with red cell volumes in excess of red cell volumes lost. Significant differences for patients transfused in excess of needs were found by sex (52.4% of women vs. 22.0% of men, P = 0.001) and by preoperative hematocrit (71.4% of patients with lower hematocrit vs. 24.1% of patients with higher hematocrit, P = 0.001). CONCLUSIONS: Preoperative hematocrit and sex can be a overtransfusion-triggering index.

A Comparison of Femoral and Radial Artery Pressure during an Adult Liver Transplantation / 대한마취과학회지

BACKGROUND: The radial artery pressure is known to differ from central arterial pressure in normal patients (distal pulse amplification) and in the early postcardiopulmonary bypass period. We assumed that there may be a change in the normal relationship between central and peripheral arterial pressure in patients with hepatic failure due to an arterio-venous shunt caused by vasodilation and a complex surgical procedure with major vessel clamping. This study was done to examine the adequacy of the radial artery as a site for blood pressure monitoring in liver transplantation (TPL). METHODS: We investigated when the pressure gradient developed and what mechanism could be responsible by comparing femoral to radial artery pressure in 11 patients undergoing liver transplantation. Radial and femoral artery pressures, systemic vascular resistance, cardiac output and temperature were compared during surgery in all 11 patients. Additionally measurements included pH, PaO2, PaCO2, central venous pressure, pulmonary artery pressure and mixed venous oxygen saturation. RESULTS: The femoral artery systolic pressure was higher than the corresponding radial artery pressures during the operation. Although not statistically significant, the radial mean and diastolic artery pressures were lower than corresponding the femoral artery pressure. CONCLUSIONS: Radial artery systolic pressures underestimate the femoral artery pressure when undergoing a liver TPL. Failure to recognize these effects on pressure recordings can lead to inappropriate patient management decisions.

Unanticipated Post-anesthesia Admission to the Pediatric Intensive Care Unit / 대한마취과학회지

BACKGROUND: Unanticipated admission to the pediatric intensive care unit (PICU) associated with anesthesia may serve as an outcome measure to evaluate the quality of anesthesia care and as education material for residency training. METHODS: We reviewed the unanticipated PICU admissions after anesthesia during 1 year period in order to analyze patient pattern, causes, and specific therapeutic interventions. We also determined whether there were any preventable anesthetic factors responsible for PICU admission. RESULTS: There were 640 admissions to PICU from operating theatres, with 8 unanticipated admissions. Age of the patients ranged from 4 months to 14 years. The unanticipated admissions were distributed to all of the surgical departments. Of 8 unanticipated admissions, only one was considered a preventable feature and had intensive care. CONCLUSIONS: The unanticipated admissions to PICU from the operation theatre were not associated with age or department of surgery. The majority of the causes of unanticipated admission were respiratory problems, which show that the pediatric anesthesiologists have to pay special attention to the respiratory system during anesthesia.

Anesthetic Management of Children with Takayasu's Arteritis: Case reports / 대한마취과학회지

Takayasu's arteritis is a rare, chronic progressive panarteritis involving the aorta and its main branches. Anesthesia for patients with Takayasu's arteritis is complicated by their severe uncontrolled hypertension and end-organ dysfunction resulting from hypertension, stenosis of major blood vessels affecting regional circulation, and difficulties encountered in monitoring arterial blood pressure. We report two cases of anesthetic management in pediatric patients who had Takayasu's arteritis. One was a case of general anesthesia for an ophthalmic laser operation and the other was a case who needed sedation during an aortic stent insertion.

The Effects of Hemodilution on Critical Oxygen Deliveries during Deliberate Hypotension by Esmolol or Sodium Nitroprusside in Dogs / 대한마취과학회지

BACKGROUND: Acute normovolemic hemodilution (ANH) and deliberate hypotension (DH) are methods used for reducing homologous transfusions in cases of massive intraoperative bleeding. Using the technique of combining ANH and DH, we can save more homologous blood than a single use of ANH or DH, but the risk of tissue hypoxia may increase. METHODS: Fourteen male dogs were used for this study and divided into two groups. After performing ANH by 25 ml/kg, mean arterial pressures were reduced to 60 mmHg by sodium nitroprusside (S group) or esmolol (E group). The critical oxygen delivery and the hemoglobin concentration at the critical oxygen delivery were determined by measurements of hemodynamic change, systemic oxygen delivery and systemic oxygen consumption during subsequent hemodilution. RESULTS: After performing ANH by 25 ml/kg, the cardiac output was significantly increased, and systemic vascular resistance and hemoglobin concentration were significantly decreased compared with control values. The critical oxygen deliveries were 179.6 ml/min in the S group and 169.1 ml/min in the E group. There was a difference in mean systemic oxygen consumption between the S group (123.4 +/- 16.7 ml/min) and E group (112.9 +/- 15.4 ml/min) above the critical oxygen delivery point (mean +/- SD). The hemoglobin concentrations at the critical oxygen delivery were 2.6 +/- 0.7 g/dl in S group and 4.0 +/- 1.3 g/dl in E group (mean +/- SD). CONCLSIONS: The critical oxygen delivery during hemodilution under DH by sodium nitroprusside was 179.6 ml/min and by esmolol was 169.1 ml/min. However, esmolol was higher in hemoglobin concentrations at the critical oxygen delivery than sodium nitroprusside. These results suggest thathemodilution under DH by esmolol rather than sodium nitroprusside requires more careful monitoring of systemic oxygen delivery for prevention of tissue hypoxia.

Attenuating Effect of cAMP on Hypoxic Pulmonary Vasoconstriction in the Isolated Perfused Rat Lungs / 대한마취과학회지

BACKGROUND: Pulmonary vessels constrict when they are exposed to hypoxia, unlike other vessels. It is hypothesized that the decreased concentration of cAMP in the hypoxic condition causes this reaction, HPV (hypoxic pulmonary vasoconstriction). When cAMP concentration is increased by either activating adenylate cyclase, using adenosine, or inhibiting the cAMP hydrolysing enzyme, phosphodiesterase type 3, using amrinone, then HPV can be reversed. The aims of this study were to develop HPV in an isolated perfused rat lung preparation, and to investigate the vasodilating effects of adenosine and amrinone on HPV. METHODS: Isolated lungs from male rats (270 330 g) were ventilated with a normoxic gas mixture (21%O2-5%CO2-74%N2) or a hypoxic gas mixture (3%O2-5%CO2-92%N2) alternately, and perfused with calcium-containing perfusate solution. Adenosine (6 x 100-2 microgram, n = 6) and amrinone (5 x 101-3 microgram, n = 6) were mixed to perfusate solution, and the initial hypoxic pressor response { Pin = Pmax (maximum pulmonary artery pressure) - Pin (initial pulmonary artery pressure)} and hypoxic pressor responses after drug administration { Pdrug = Pmax (maximum pulmonary artery pressure) - Pbase (baseline pulmonary artery pressure)} were measured. Meclofenamate was used to block prostaglandin-mediated vasorelaxation. RESULTS: Adenosine did not decrease Pdrug compared to Pin. But amrinone inhibited HPV effectively a with a linear dose-response relationship (r = 0.842, P< 0.05). y = 26.72 x log (x) 35.79y: % relaxation = 100 [ Pdrug/ Pin] 100 , x: amount of drug, microgram, CONCLUSIONS: Amrinone attenuated HPV, and it can be concluded that increased levels of cAMP helpful to relax pulmonary vessels in hypoxic condition.

A Case of Anesthetic Management for a Pregnant Woman with Unruptured Cerebral Aneurysm Undergoing Simultaneous Cesarean Section and Aneurysm Clipping: A case report / 대한마취과학회지

Intracranial aneurysm in pregnancy imposes special consideration for both mother and fetus. During newborn delivery, the risk of aneurysmal rupture should be avoided by careful management. We experienced a case of cesarean section and the clipping of aneurysm in 37 years old pregnant woman at the gestational age of 35 weeks. She had suffered from headache since 30 weeks of gestational age and the ptosis of left eye since 33 weeks of gestational age. Ten millimeter-sized aneurysm of posterior communicating artery was found on the cerebral angiogram. After radial artery cannulation, we anesthetized the woman with nitroprusside infusion, thiopental, succinylchoine and nitrous oxide-oxygen-isoflurane gas mixture. Soon after intubation, systolic blood pressure increased from 140 to 150 mmHg during the infusion of sodium nitroprusside. The delivery of a newborn was done 8 min after induction and clipping of aneurysm was done successfully after the end of cesarean section.

The Effect of General and Epidural Anesthesia in Women undergoing Cesarean Section on Power Spectral Components of Heart Rate Variability: Clinical Study / 대한마취과학회지

BACKGROUND: The analysis of beat-to-beat heart rate variability has become a method of assessing the state and health of the autonomic nervous system. Power spectral analysis(PSA) has become one of the most widely used techniques to describe heart rate variability. METHODS: We analyzed the heart rate variability using PSA before and during general and epidural anesthesia in cesarean section. We anesthetized 12 patients by enflurane, and 15 patients by 2% lidocaine via epidural catheter. Automatic computer analysis provided PSA. The PSA contained two major components, a low frequency(LF) at 0.04~0.15 Hz, and a high frequency(HF) at 0.15-0.50 Hz. RESULTS: Before anesthesia, P(LF)(spectral power of LF-unit; sec2/Hz) is 0.06(0.03, 0.34) {median(5 percentile, 95 percentile)}, P(HF), 0.83(0.22, 1.68), total spectral power(Ps), 1.98(O.86, 3.88), and P(LF)/P(HF), 0.67(0.17,1.67) in general anesthesia group. During anesthesia, P(LF) is 0.06(0.03, 0.34), P(HF), 0.12(0.04, 0.76), Ps, 0.43(0.24, 1.71), P(LF)/P(HF), 0.70(0.24, 2.59). In epidural group, before anesthesia, P(LF) is 0.30(0.11, 1.94), P(HF), 0.78(0.14, 1.94), Ps, 1.81(0.58, 5.23), P(LF)/P(HF) 0.47(0.25, 1.34). During anesthesia, P(LF). is 0.14(0.05, 0.41), P(HF), 0.33(0.07, 0.80), Ps, 0.81(0.34, 1.58), P(LF)/P(HF), 0.58(0.22, 1.08). CONCLUSIONS: In general anesthesia, P(LF) P(HF) and Ps during anesthesia showed significant decrease than pre-anesthetic period, but P(LF)/P(HF) did not change. In epidural anesthesia, P(LF)/P(HF) and Ps during anesthesia also decreased, but P(LF)/P(HF) did not change. There were significant differences in degree of decrease in Ps and P(HF) between general and epidural anesthesia, but no differences in and P(LF)/P(HF).

The Effect of General and Epidural Anesthesia in Women undergoing Cesarean Section on Power Spectral Components of Heart Rate Variability: Clinical Study / 대한마취과학회지

BACKGROUND: The analysis of beat-to-beat heart rate variability has become a method of assessing the state and health of the autonomic nervous system. Power spectral analysis(PSA) has become one of the most widely used techniques to describe heart rate variability. METHODS: We analyzed the heart rate variability using PSA before and during general and epidural anesthesia in cesarean section. We anesthetized 12 patients by enflurane, and 15 patients by 2% lidocaine via epidural catheter. Automatic computer analysis provided PSA. The PSA contained two major components, a low frequency(LF) at 0.04~0.15 Hz, and a high frequency(HF) at 0.15-0.50 Hz. RESULTS: Before anesthesia, P(LF)(spectral power of LF-unit; sec2/Hz) is 0.06(0.03, 0.34) {median(5 percentile, 95 percentile)}, P(HF), 0.83(0.22, 1.68), total spectral power(Ps), 1.98(O.86, 3.88), and P(LF)/P(HF), 0.67(0.17,1.67) in general anesthesia group. During anesthesia, P(LF) is 0.06(0.03, 0.34), P(HF), 0.12(0.04, 0.76), Ps, 0.43(0.24, 1.71), P(LF)/P(HF), 0.70(0.24, 2.59). In epidural group, before anesthesia, P(LF) is 0.30(0.11, 1.94), P(HF), 0.78(0.14, 1.94), Ps, 1.81(0.58, 5.23), P(LF)/P(HF) 0.47(0.25, 1.34). During anesthesia, P(LF). is 0.14(0.05, 0.41), P(HF), 0.33(0.07, 0.80), Ps, 0.81(0.34, 1.58), P(LF)/P(HF), 0.58(0.22, 1.08). CONCLUSIONS: In general anesthesia, P(LF) P(HF) and Ps during anesthesia showed significant decrease than pre-anesthetic period, but P(LF)/P(HF) did not change. In epidural anesthesia, P(LF)/P(HF) and Ps during anesthesia also decreased, but P(LF)/P(HF) did not change. There were significant differences in degree of decrease in Ps and P(HF) between general and epidural anesthesia, but no differences in and P(LF)/P(HF).

A Case of Endotracheal Tube Injury during Maxillofacial Surgery: Case report / 대한마취과학회지

An endotracheal tube provides patent airway during general anesthesia. We experienced the cutting of an endotracheal tube during surgical procedure. The patient with bimaxillary protrusion was operated for cosmetic bimaxillary surgery. The patient was intubated via nasotracheal route with a reinforced endotracheal tube. During surgical procedure, we found air bubbles from the nostril in which the entotracheal tube was inserted. Several milliliters of air was infused into the pilot balloon to inflate the cuff, but air bubbles was noticed continuously. We exchanged the endotracheal tube using a tube exchanger. The removed endotracheal tube was partially cut at 22cm from the tip, probably due to the air-driven saw.

Variables Affecting the Level of Epidural Anesthesia for Cesarean Section / 대한마취과학회지

To determine whether age, weight, height, vertebral column length, body mass index, or abdominal circumference might influence the distribution of sensory analgesia after epidural anesthesia, 100 women presenting for cesarean section were studied. All received 26 mg of 2.0% lidocaine mixed with 8.4% bicarbonate 1 ml/lidocaine 10 ml and 1:300,000 epinephrine, including 3 ml of test dose, through the epidural catheter inserted in L3-4 interspace. While the women lay supine on a horizontal operating table with the air bag under their right hip, 2, 5, 10, 20, and 30 minutes after injection, the cephalad extent of sensory analgesia (loss of sensation of sharpness to pin prick) was determined. Age (31.9+/-3.8 years), weight (69.2+/-9.3 kg), height (158.9+/-4,5 cm), vertebral column length (59.8+/-5.0 cm), body mass index (27.4+/-3.2 kg/m(2)), and abdominal circumference (103.5+/-10.2 cm) did not correlate with the maximum level of sensory analgesia. In conclusion, in parturients of age, weight, height, vertebral column length, body mass index and aMominal circumference of the above values, it is not necerrary to vary dose of injected local anesthetics with changes in any of the patient variables studied.

The Causes of Delaying or Cancellation of the Elective Surgery in Pediatric Patients / 대한마취과학회지

We examined the causes of delaying or cancellation of the elective surgery at Seoul National University Children's Hospital. The total numbers of pediatric patient for the elective surgery during September 1, 1994, to November 30, 1994, were 1287 and that of delaying or cancellation of surgery were 135. The fraction of medical causes of delaying of the elective surgery was 62.2%, and that of non-medical causes of the elective surgery was 36.3%, and 1.5% was unknown. The single most frequent cause was upper respiratory infection, 42.2% of total delays, and the second was that patient had not be admitted as 16.3%o of total delays. The third frequent cause was no indication for surgery as 6.7%, the fourths were fever and inadequate preparation for surgery (5.2%), and the sixth was that the patient had refused to give an informed consent (3.7%), etc.