The Effects of Arterial Oxygen Tension following Indueed. Hypotension with Sodium Nitroprusside / 대한마취과학회지

The effect of sodium nitroprusside(SNP) on arterial oxygen tension in 20 neurosurgical patients with normal lung function was studied under general anesthesia. Blood gas, heart rate, mean arterial pressure and central venous pressure were measured before, during and after SNP infusion. The results were as follows:1) Arterial oxygen tension significantly decreased from 177+/-40.6 mmHg before SNP to 138+/-50.1 mmHg during SNP(p<0.005), and increased again to 168+/-44.4 mmHg after SNP. 2) Mixed venous oxygen tension decreased 47+/-8.2 mmHg to 40+/-7.3 mmHg(p<0.005), and increased again to 44+/-10.3 mmHg. 3) Heart rate significantly increased from 92+/-24.6 beats/min to 118+/-27.4 beats/min(p<0.005), and decreased again to 94+/-18.6 beats/min. The above findings have shown a marked reduction in PaO2 when SNP was administered during general anesthesia. After SNP, PaO2, returned to the previous values. It is suggested that the reduction in PaO2, is the result of an increased scatter of ventilation/perfusion relationships in the lung and inhibition of hypoxic pulmonary vasoconstriction by SNP. These results provide evidence that SNP induced hypotension may cause significant impairment in pulmonary gas exchange in patients with normal lung function.

Effects of Unilateral Hypoxic Ventilation upon Pulmonary Hemodynamics and Intrapulmonary Shunt in Dogs / 대한마취과학회지

The effects of unilateral hypoxic ventilation on pulmonary hemodynamics, alveolar-arterial oxygen tension difference (A-aDO2) and intrapulmonary shunt in 10 dogs were studied under unilateral hypoxic ventilation using nitrogen. Hear rate, mean arterial pressure, central venous pressure, mean pulmonary arterial pressure, pulmonary capillary wedge pressure, cardiac output, blood gases and hemoglobin were measured during controlled ventilation with 100% oxygen and unilateral hypoxic ventilation. Using the above steps pulmonary hemodynamics, (A-a)DO2 and intrapulmonary shunt were calculated and the following results were obtained. 1) Mean pulmonry arterial pressure significantly increased (20%) from 20.6+/-2.60mmHg to 24.8+/-2.46mmHg(p<0.005) and pulmonary vascular resistance also significantly increased(43%) from 434+/-68.4 dynee. sec/cm(2) to 605+/-81.0 dynes. sec/cm(2)(p<0.005), whereas the cardiac output decreased (8%) from 1.92+/-0.23 l/min to 1.76+/-0.21 l/min(p<0.05) after unilateral hypoxic ventilation. 2) Alveolar-arterial oxygen tension difference significantly increased from 180+/-23.2mmHg to 470+/-31.9mmHg(p<0.005) after unilateral hypoxic ventilation. 3) Intrapulmonary shunt significantly increased from 9.5+/-1.40% to 24.8+/-2.02%(p<0.005) after unilateral hypoxic ventilation, but it was much lower than the mathematically expected value(40% over). The above findings suggest the operation of a protective mechanism, which causes hypoxic pulmonary vasoconstriction in the unilateral hypoxic lung, and diverts blood flow from the hypoxic to the non-hypoxic lung and so minimizes the hypoxic effect on the arterial blood.

Anesthetic Management for the Patient with Von Gierke`s Diseases / 대한마취과학회지

Glycogen storage disease is a rare metabolic disorder of significant to the anesthesiologist. The term "glycogen storage disease" is applied to a group of congenital and familial disorders characterised by depostion of abnormally large or small quantities of glycogen in the tissues. 13 types of glycogen storage diseases have been described, classified on the basis of enzyme deficiencies. Type l glycogen storage disease (von Gierke's Disease) is the most common of this constellation of syndromes. The basic defect is a deficiency of enzyme, glucose-6-phosphatase. The patient has hepatomegaly, renomegaly, stunted growth, a tend toward severe hypoglycemia and acidoais. The adverse effect of the combined anesthetic and surgical procedure during operation was reflected in a deterioration of the patients's biochemical parameters. A cardiac arrest after tonsillectomy of the patient with Von Gierke's disease was reported and this fact cmphasizes serious anesthetic problems during operation. Anesthetic management of these patients should focus on prevention of hypoglycemia and lactic acidosis. The careful frequent measuring of the acid-base status is highly recommended and is essential prior to and during andy surgical procedure. We report a case of anesthetic management for a patient with Von Gierke's desease ane review anesthetic problems for these patients.

A Changes in Blood Pressure with Varying Rates of Adminstration of d-Tubocurarine / 대한마취과학회지

d-tubocurarine is one of the non-depolarizing muscle relaxants which is most commonly used in clinical situations d-Tc is used as a selective muscle relaxant in hypertensive patients or patients for renal transplantation. The most common side effect of d-Tc is a dose-related fall in arterial pressure. Although the cause of the hypotension is still controversial, the two mechanism most frequently suggested are ganglionic block and histamine release. d-Tc is an active ganglionic blocking agent. Howver, because its potency at the neuromuscular junction is greater than at the ganglia, there is some doubt that a clinical concentration of d-Tc is sufficient to cause hypotension. histamine release may play a role in this blood pressure reduction. Indeed, decrease in blood pressure produced by d-Tc have been shown to be less when the muscle relaxant was preceded by and antihistamine. The amount of histamine release substance depends on plasma levels of the drug achieved and thus on the rapidity of intravenous administration of that drug. If d-Tc produces histamine release, then slow intravenous injection would be associated with minimal histamine release and a resulting attenuation of the typical blood pressure reduction that follows' this drugs injection. Therefore, we measured changes in mean arterial pressure(MAP) and heart rate in patients anesthetized with nitrous oxide-halothane during and after the intravenous injection of d-Tc at varying rates of administration. The results are as follows: 1) Group 1: Maximum reduction in MAP were present 3 minutes following d-Tc injection over 1 second (81+/- 3 torr). Comparative with control group (99+/-6 torr), significant reduction was revealed(18.1%). 2) Group 2: Decrease in MAP 3 minutes after administration of d-Tc over 90 seconds(11.1%) were intermediate between the other injection rates. 3) Group 2: Decrease in MAP 3 minutes after d-Tc administration was significantly less in patients receiving the drug over 180 seconds(5.1%). Heart rate did not change significantly after d-Tc injection regardless of the rate of administration.

The Change of Heart Rate following the mixed injection of Atropine and Neostigmine for Non-Depolarizing Neuromuscular Blocking Agent-Pancuronium / 대한마취과학회지

Around the time of recovery from general anesthesia we usually use atropine and neostigmine to counteract the effect of muscle relaxant that is remaining in the body. We used various kinds of combinations of atropine and neostigmine to see the effect of them on heart rate. The combinations were as follows: I) atropine 0.02mg/kg+neostigmine 0. 02mg/kg. 2) atropine 0. 2mg /kg+neostigmine 0.03mg/kg. 3) atropine 0. 02mg/kg+neostigmine 0.04mg/kg. 4) atropine 0.02mg/kg+neostigmine 0.05mg/kg. 5) atropine 0.02mg/kg+neostigmine 0.06mg/kg. 6) atropine 0.02mg/kg+neostigmine 0.07mg/kg. Ten subjects(ps.I.ASA) were taken for each combination. Thus total sample size of the six combinations were sixty, Each study has been performed in the state of ASA P.S.1, and anesthetized for b but two hours. N2O-O2-Halothane technique was used for anesthesia. The dosage of pancuronium was 0. 08mg/kg. The age distribution of the sample was 2 to 60, and male to female ratio was 4 to 6. We came to the following conclusions from this study. 1) Types of dosage combinations those caused little change in heart rate were; atrop!ne 0.02mg/kg+neostigmine 0.02mg/kg, and atropine 0.02mg/kg+ neostigmine 0.03mg/kg. 2) Just after the simultaneous injection of the drugs, there appeared mild tachycardia, but fifteen minutes after the administration severe bradycardia came on and, after that the heart rate returned to normal. 3) The combinations which included neostigmine, more than 0. 04mg/kg, caused severe braycardia, and the most severe bradycardia was seen with a combination of atropine 0.02mg/kg and neostigmine 0.06mg/kg.

A Clinical Study on Changes of Body Temperature before and after Extracorporeal Circulation for Open Heart Surgery / 대한마취과학회지

Changes of body temperature were observed in the esophagus and rectum by telethermometer during extracorporeal circulation in 40 cases of open heart for detection of significant differences in survivals and non-survivals. The following results were obtained; 1) Esophageal and rectal temperature(just prior to extracorporeal circulation) were 36.4+/-0.69 degrees C, 36.8+/-0.8 degrees C respectively in non-survivals and 36.0+/-0.73 degrees C, 36.4+/-0.8 degrees C in survivals after open heart surgery 2) Normal differences between rectal and esophageal temperature came to disappear after 30 minutes of extracorporeal circulation in two groups. 3) Esophageal temperatures were higher than rectal temperatures after extracorporeal circulation for open heart surgery in both groups. 4) Changes of temperature differences between rectum and esophagus have no correlation with mortality because of the variation in two areas in both groups.

A Clinical Study on Respiratory Intensive Care in Critically Ill pateints ( The Second Report ) / 대한마취과학회지

A clinical study was made of 480 patients on respiratory intensive care, which is 4.6%, of 10, 390 patients who were admitted to the postanesthetic recovery room for three years from 1976 to 1978 in Seoul National University Hospital(SNUH) The highest age group was the 11 to 20 year old group. Among 480 patients males were 58. 4%, females 41. 6%. The duration of mechanical ventilation was shortest in the open heart surgery group (32.3 hours). Death rates among diseases and types of ventilators are listed. Standard of weaning in mechanical ventilation are discussed. The pulmonary pathophysiologic involvement in critically ill patients are discussed with the literature.

An Experimental Study of the Effects of Muscle Relaxants on the Intraocular Pressure / 대한마취과학회지

Since succinyl choline was introduced, into clinical anesthesia, it has been used as main muscle relaxant because of its rare side effects and short duration of action. Our interest in the effects of this drug on extraocular muscles and intraocular pressure began in 1957 following reports of vitreous expulsion in patients who received succinylcholine during ocular surgery. The effects of muscle relaxants on the intraocular pressure were studied in 60 healthy human subjects. When succinylcholine was given alone, 20 human subjects had a mean increase in intraocular pressure of 10. 5 mmHg. When gallamine 2. 5 mg/kg or pancuronium 80 ug/kg was used, 20 subjects showed a mean decrease of 3. 1 mm Hg from control. Giving gallamine (20 mg) or dtubo curarine(3 mg) 2-3 minutes prior to the administration of succinylcholine, 20 human subjects had no significant change in intraocular pressure. This simple method prevents the increase in intraocular pressure associated with the use of succinylcholine.

An Experimental Study of Positive End-Expiratong Pressure ( PEEP ) on Blood Gases during General Anesthesia / 대한마취과학회지

Salient features of acute respiratory failure are reduction of functional residual capacity, decreasedlung compliance and increased right to left shunt; and pneumonia, pulmonary congestion, atelectasis pulmonary edema and fibrosis are revealed clinically. PEEP is able to prevent alveolar collapse and avoid atelectatic change and increase functivnal residual capacity and lung compliance with increment of arterial oxygen content. Decreased cardiac output and pulmonary parenchymal damages were noted during high PEEP. Blood gases were observed with IL 213 Blood Gas Analyzer during 5cm H2O of PEEP and general anesthesia in 10 healthy persons. Following results were obtained: 1) 5 cm H2O of PEEP increased PaO2 from 221 torr to 275 torr and PaCO2 from 38. 8 torr to 42. 1 torr. 2) 5 cm H2O of PEEP increased PvO2 from 40 torr to 48 torr and PvCO2 from 44. 1 torr to 49. 3 torr. 3) 5 cm H2O of PEEP increased mean arterial pressure but had no effect on heart rate. 4) 5 cm H2O of PEEP increased C(a-v)DO2 from 5. 306 cc/100ml to 5. 433 cc/100ml. 5) It is noted that 5 cm H2O of PEEP is safe in healthy persons.

A Clinical Study on Doses of the Anesthetic Agents for Open Heart Surgery / 대한마취과학회지

It was Observed required doses of morphine and pancuronium bromide or d-tubocurarine in 34 cases of open heart anesthesia which performed between October 1, 1974 and August 31, 1975 is SNUH with the induction of sleeping dosea of 2.5% thiopental and succinyIcholine for intubation, and maintenance of 50% of nitrous oxide and oxygen. It was obtained the results as followings: 1. The average required dose of morphine in open heart anesthesia was 0.34+/-0.25 mg/kg body weight (34 cases). 2. The average required dose of pancuronium bromide in open heart anesthesia was 0.212+/-0.091mg/kg body weight (28 cases). 3. The average required dose of d-tubocurarine in open heart anesthesia was 0.745+/-0.298 mg /kg body weight (8 cases); 4. The duration of open heart anesthesis and extracorporeal circulation were 396 minutes and 102.8 minutes respectively. 5. Discussion on the small dose of morphine in open heart anesthesia performed with literatures.

A Report of Unusual Anesthetic Managements of Pheochromocytoma / 대한마취과학회지

It has been emphasized that continuous monitorings of arterial pressure, central venous pressure, electrocardiogram, blood gas analysis, serum electrolytes, body temperature, hematacrit and urinary output are mandatory for the anesthetic management of pheochromocytoma. In addition, it is necessary for the anesthetists to understand pharmacologic effects of drugs which influence the peripheral vascular tone and cardiac excitability. We experienced recently anesthetic management of two cases of pheochromocytoma; one raised problems of ventricular arrhythmias and hypertension that aggravated nature of arrhythrmias by increasing blood pressure and responded favorably to treatment with propranolol and trimetaphan. Tumor of this case originated from abdominal aortic wall. The other was managed by injection of d-tubocurarine which induced narrowing of pulse pressure by depletion of increasing systolic pressure and accompanied tachycardia without cardiac decompensation. We have reported proper anesthetic managements of two cases of pheochromocytoma with N2O O2-halothane anesthesia and reviewed literatures in discussion.