BACKGROUND: Nitric Oxide (NO) has been discovered to be an important endothelium-derived relaxing factor. The exogenous inhaled NO may diffuse from the alveoli to pulmonary vascular smooth muscle and produce pulmonary vasodilation, but any NO that diffuses into blood will be inactivated before it can produce systemic effects. To examine the effects of NO on pulmonary and systemic hemodynamics, NO was inhaled by experimental dogs in an attempt to reduce the increase in pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR) induced by hypoxia in dogs. METHODS: Eight mongrel dogs were studied while inhaling 1)50% O2 (baseline), 2)12% O2 in N2 (hypoxia), 3)followed by the same hypoxic gas mixture of O2 and N2 containing 20, 40 and 80 ppm of NO, respectively. RESULTS: Breathing at FIO2 0.12 nearly doubled the pulmonary vascular resistance from 173 56dyn sec cm-5 to 407 139dyn sec cm-5 and significantly increased the mean pulmonary artery pressure from 16 3mmHg to 22 4mmHg. After adding 20~80 ppm NO to the inspired gas while maintaining the FIO2 at 0.12, the mean pulmonary artery pressure decreased (p<0.05) to the level when breathing oxygen at FIO2 0.5 while the PaO2 and PaCO2 were unchanged. The pulmonary vascular resistance decreased significantly and the right ventricular stroke work index returned to a level similar to breathing at FIO2 0.5 by addition of NO into the breathing circuit. Pulmonary hypertension resumed within 3~5 minutes of ceasing NO inhalation. In none of our studies did inhaling NO produce systemic hypotension and elevate methemoglobin levels. CONCLUSIONS: Inhalation of 20~80 ppm NO selectively induced pulmonary vasodilation and reversed hypoxic pulmonary vasoconstriction without causing systemic vasodilation and bronchodilation. Methemoglobin and NO2 were within normal limit during the study.
Animals ; Anoxia ; Dogs ; Endothelium-Dependent Relaxing Factors ; Hemodynamics* ; Hypertension, Pulmonary ; Hypotension ; Inhalation* ; Methemoglobin ; Muscle, Smooth, Vascular ; Nitric Oxide* ; Oxygen ; Pulmonary Artery ; Respiration ; Stroke ; Vascular Resistance ; Vasoconstriction* ; Vasodilation

BACKGROUND: To reduce the risk of Mendelson's syndrome, it is customary to fast patients for 8 hours before anesthesia. However preoperative fast is unpleasant for patients, who complain frequently of thirst and dry mouth, and this conventional fast may be over-cautious. We have studied the effect of ingestion of barley tea, a Korean popular beverage, 3 hours before anesthesia on gastric contents (volume and pH), blood sugar level, thirst, and anxiety. METHODS: We studied prospectively 284 adult patients undergoing elective surgery. The patients in the control group (n=142) fasted for at least 8 hours, and those in the experimental group (n=142) received 250 ml of barley tea 3 hours before anesthesia. On arrival in the operating room, subjects were asked to assess thirst and anxiety. After induction of anesthesia, gastric contents were aspirated via 18 French Salem sump tube and gastric volume, pH and blood sugar level were measured. RESULTS: There were no statistically significant differences in gastric fluid volume and pH and blood sugar level between control and experimental groups. However, patients in experimental group complained of less thirst than those in control group. CONCLUSIONS: This study demonstrates that in adult patients undergoing elective surgery, allowing patients to drink 250 ml of barley tea until 3 hours before anesthesia may relieve patients from thirst without compromising safety.
Adult ; Anesthesia ; Anesthesia, General ; Anxiety ; Beverages ; Blood Glucose ; Eating ; Hordeum ; Humans ; Hydrogen-Ion Concentration* ; Mouth ; Operating Rooms ; Pneumonia, Aspiration ; Prospective Studies ; Tea ; Thirst

BACKGROUNDS: Various methods have been devised for choosing the correct internal diameter (ID) of endotracheal tubes and the proper lengths for oral endotracheal tubes at different ages in children. This study was performed to evaluate the appropriate sizes of uncuffed endotracheal tubes and distance from upper incisor to carina in Korean children under 8 years old. METHODS: Five hundred thirty five children under 8 years in ASA class 1 and 2 were evaluated for the study by age groups: 0~3 months, 4~11 months and every each year until 8 years. Appropriate sizes were to permit a gas leak at 15~25 cmH2O with positive pressure ventilation. Distances from incisor to carina were at the point which bilateral lung sounds were noticed during slow extubation from endobroncheal intubation. RESULTS: Appropriate tube sizes were 3.0 mm to 3.5 mm for infants under 3 months, 3.5 mm to 4.0 mm for 4 to 11 months and ""4.15+0.28xage (yr) (mm)"" (R2=0.77, p<0.05) for children between 1 and 8 years old. Distances from upper incisor to carina were 12.0 cm for infants under 3 months, 13.7 cm for 4 to 11 months and ""14.5+0.6xage (yr) (cm)"" (R2=0.62, p<0.05) for children between 1 and 8 years old. CONCLUSIONS: We conclude that the endotracheal tube ID for the Korean children are a little greater than those of previous reports in foreign countries and airway lengths for the Korean children are similar to those of foreigners.
Child* ; Emigrants and Immigrants ; Humans ; Incisor* ; Infant ; Intubation ; Positive-Pressure Respiration ; Respiratory Sounds

BACKGROUND: Hypoxic pulmonary vasoconstriction (HPV) is a defense mechanism to maintain adequate oxygenation. It has been reported that metabolism inhibition augments HPV. The purpose of the present study was, therefore, to determine the effect of metabolism inhibition on HPV in a rabbit model of isolated lung perfusion with exclusion of the influential factors on HPV. METHODS: In adult rabbits, lungs were isolated and perfused with a constant pulmonary perfusate flow. Acid-base status and temperature of perfusate was also constantly maintained. Thirty minutes after, the baseline hypoxic pressor response (HPR) was measured as the difference of pulmonary artery pressure (PAP) between a period of 21% normoxic gas inhalation and that of 3% hypoxic gas inhalation. After another thirty minutes, 2-deoxy-D-glucose 100 mg was mixed with the perfusate, and then HPR was measured three times. After checking metabolism inhibition effects, D-glucose 300 mg was mixed to the perfusate to reverse metabolism inhibition, and then HPR was measured three times again. RESULTS: Metabolism inhibition increased the basal PAP compared to the noninhibition state, but it didn't increase HPV response, so the peak PAP responding to hypoxic gas was the same as the noninhibition state. The absolute HPV response was decreased. After reversal of the inhibition state with a large amount of glucose, the basal PAP decreased to the original value and the HPV response recovered to the previous value. CONCLUSIONS: Deoxyglucose-induced metabolism inhibition increased the PAP ventilated with 21% O2, but it didn't increase the PAP ventilated with 3% O2. As a result, the absolute HPV response was decreased.
Adult ; Deoxyglucose* ; Glucose ; Humans ; Inhalation ; Lung* ; Metabolism* ; Oxygen ; Perfusion ; Pulmonary Artery ; Rabbits ; Vasoconstriction*

The reliability of emergency ultrasonographic(US) detection of hemoperitoneum and solid organ injury in blunt abdominal trauma was evaluated retrospectively. From October 1,1995 to August 31,1996,90 patients were included in the study. Ultra- sonographic findings showed a sensitivity, specificity, and accuracy of 97.6%, 97.9%, and 98.1%, respectively, in detecting intraabdominal fluid collection. We believe that US in an emergency center is a quick, safe screening method in the evaluation of blunt abdominal trauma. In our department, US has replaced diagnostic peritonaeal lavage(DPL) and computed tomography(CT) as the screening study of first choice.
Emergencies* ; Hemoperitoneum* ; Humans ; Mass Screening ; Retrospective Studies ; Sensitivity and Specificity ; Ultrasonography*

BACKGROUND: The optimal depth of subclavian catheterization is not clearly and simply defined in the pediatric population. The aim of this study is to examine the relationship between the depth of the subclavian catheter and easily measured body-size variables, such as weight and height, and then to formulate a guide for the optimal depth of subclavian catheterization in the pediatric population. METHODS: We cannulated eighty-five pediatric cardiac patients via the left or right subclavian approach. The position of the catheter tip was determined by postoperative AP chest x-ray, and the length from the skin to the point of the border of superior vena cava and the right atrium (SK-SVCRA) was measured. RESULTS: Significant correlations with SK-SVCRA were found for weight and height. For the right approach, SK-SVCRA is calculated as 0.28xweight (kg) + 4.86 or 0.07 x height (cm)+1.70. For the left approach, SK-SVCRA is calculated as 0.22xweight (kg)+6.51 or 0.06xheight (cm)+3.94. CONCLUSIONS: Simple equations for the placement of the catheter tip at the border of the superior vena cava and right atrium as a function of patients' weight and height were formulated. These data may provide a useful guide to determine how deeply the subclavian catheter should be located.
Catheterization* ; Catheters* ; Heart Atria ; Humans ; Skin ; Thorax ; Vena Cava, Superior

The effects of halothane, enflurane and isoflurane on the postoperative hepatic functions were compared in 91 pediatric patients with normal preoperative hepatic funcions. After induction of anesthesia with thiopental and vecuronium, all the patients were randomly divided into three groups of halothane(n=31), enflurane(n=27) and isoflurane(n=33). Anesthesia was maintained with 1 MAC of each anesthetics combined with N2O(50%) and O2(50%). On the postoperative 1st day(POD#1), we observed elevated total bilirubin in each groups, which was normalized on the postoperative 2nd day(PDO#2). Inthergroup comparisons were not significant. SGOT was elevated on the POD#1, but returned to normal on the POD2 in halothane and isoflurane groups. SGPT showed no changes postoperatively. SGOT and SGPT were not significant between the groups. Alkaline phosphatase showed significant decrease on the POD#2 in enflurane and isoflurane groups, which was statistically significant compared with halothane group.This study shows that halothane, enflurane and isoflurane has no hamful effects on the postoperative hepatic functions, when they are administered in the pediatric patients with normal preoperative hepatic funcions.
Alanine Transaminase ; Alkaline Phosphatase ; Anesthesia ; Anesthetics ; Aspartate Aminotransferases ; Bilirubin ; Child* ; Enflurane* ; Halothane* ; Humans ; Isoflurane* ; Liver ; Thiopental ; Vecuronium Bromide

Rapid eeonomic divelopment and attendent technological advances have influenced the practice of anesthesia as well as other medical fields. Our fields such as CPR, respiratory care, critical role of an anesthesilogist has been extended beyond the confines of the operating theater in the developed countries. In Korea, the chronic shortage of manpower tends to restrict anesthesiologists to operating theater providing minimal time for preoperative assessment and more active contact with patients. In our survey to 150 senior medical students, opportunity for direct patient contact is the most important determinant in the choice of a career. The medical graduates interests in clerkship in College of Medicine, Seoul National Universty, in order, are respiratory care/mechanical ventilation, endo- tracheal intubation, arterial blood gas/it's interpretation, cardiopulmonary resuseitation and anesthesia per se. Their most favorite specialties in order as a career choice are internal medicine, ENT, et., and anesthesiology is ranked between 7th and 11th specialty.
Anesthesia ; Anesthesiology* ; Cardiopulmonary Resuscitation ; Career Choice ; Critical Care ; Developed Countries ; Humans ; Internal Medicine ; Intubation ; Korea ; Seoul ; Students, Medical ; Ventilation

Background: Myringotomy with tympanostomy tube insertion (MTI) is a superficial surgical procedure used to prevent hearing loss in children with serous otitis media. Intravenous anesthesia, often ketamine, is preferred for this procedure because of its ability to induce sedation without compromising airway reflexes. However, ketamine alone may be insufficient and potentially lead to spontaneous movement during surgery. This study evaluated the effectiveness of midazolam and fentanyl as adjuvants to ketamine in reducing spontaneous movement during MTI and enhancing the quality of recovery. Methods: This study involved two groups of 30 patients each: one group received intravenous ketamine (1.5 mg/kg) with an equal volume of normal saline (K group), while the other received a combination of midazolam, fentanyl, and ketamine (0.05 mg/kg, 1 μg/kg, and 1.5 mg/kg, respectively; MFK group). We assessed side effects, intraoperative patient movement, surgeon satisfaction, and emergence agitation scores. Results: The MFK group exhibited significantly lower scores for patient movement (p<0.01) and emergence agitation (p<0.01) and markedly higher surgeon satisfaction scores (p<0.01) than the K group. Conclusion Administering a midazolam-fentanyl-ketamine combination effectively reduced spontaneous movement during surgery and emergence agitation during recovery without prolonging discharge times in children undergoing MTI.

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.
Adenosine ; Adenylyl Cyclases ; Amrinone ; Animals ; Anoxia ; Humans ; Lung* ; Male ; Meclofenamic Acid ; Pulmonary Artery ; Rats* ; Relaxation ; Vasoconstriction* ; Vasodilation