• The Korean Journal of Physiology
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• v.21 no.2
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• pp.211-223
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• 1987

Head-down tilt (HDT) at $-6^{\circ}$ has been commonly used as the experimental model in both man and animals to induce the blood shift toward the head or central protion of the body, demonstrating similar physiological effect encountered in the weightlessness in the orbital flight. There are few reports about the physiological response upon the cardiovascular regulatory system or the tolerance to the $(-6^{\circ})$ HDT within a relatively short period less than 1 hour. Therefore, the purpose of this study way to observe the effects of $-6^{\circ}$ HDT on cardiovascular system within 30 minutes and to evaluate early regulatory mechanism for simulated hypogravity. Ten mongrel dogs weighing 8-12 kg were anesthetized with the infusion of 1% ${\alpha}-chloralose$ (100 mg/kg) intravenously, and the postural changes were performed from the supine to the $-6^{\circ}$ head-down Position, then from the head-down to the supine (SUP), and each posture was maintained for 30 minutes. Blood flow $({\dot{Q}})$ through common carotid and femoral arteries were determined by the electromagnetic flowmeter. Mean arterial pressure (MAP), heart rate (HR), respiratory rate , and pH, $P_{O_2}$, $P_{CO_2}$ and hematocrit (Hct) of arterial and venous blood were also measured. The peripheral vascular resistance was calculated by dividing respective MAP values by ${\dot{Q}}$ through both sides of common carotid or femoral arteries. The concentration of plasma epinephrine and norepinephrine was determined by Peuler & Johnson's radioenzymatic method. The results are summarized as follows: In the initial 5 minutes in $-6^{\circ}$ HDT, HR was significantly (p<0.05) increased and MAP slightly decreased. Although ${\dot{Q}}$ and carotid peripheral artery resistance were not significantly changed, ${\dot{Q}}$ through femoral artery was diminished and femoral peripheral artery resistance was elevated. In the SUP, the initial changes of MAP and HR were increased (p<0.05), but those of ${\dot{Q}}$ and peripheral vascular resistance through both common carotid and femoral arteries were not significant. After 10 minutes of each postural change in both HDT and SUP, MAP was maintained almost equal to that of the level of pretilting control. During 60 minutes of both postural changes of HDT and SUP, $P_{O_2}$ and Hct were not changed significantly. However pH tended to increase slowly and $P_{CO_2}$ was gradually decreased. The pH and $P_{CO_2}$ seemed to be related to the increased respiratory rate. Plasma epinephrine concentration was not changed significantly and plasma norepinephrine concentration was slightly decreased in the course of HDT and also at 10 minutes of SUP. However these concentration changes were statistically insignificant. From these results, it may be concluded that the effect of $-6^{\circ}$ HDT for 30 minutes on the cardiovascular system and plasma catecholamine levels of the dog is minimum and it is suggestive that the cardiovascular regulatory mechanism, possibly mediated by so called gravity receptors including baroreceptor and volume receptor, has been properly and adequately operated.

• Tuberculosis and Respiratory Diseases
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• v.43 no.2
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• pp.190-200
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• 1996

Background : Mechanical ventilation constitutes the last therapeutic method for acute respiratory failure when oxygen therapy and medical treatment fail to improve the respiratory status of the patient. This invasive ventilation, classically administered by endotracheal intubation or by tracheostomy, is associated with significant mortality and morbidity. Consequently, any less invasive method able to avoid the use of endotracheal ventilation would appear to be useful in high risk patient. Over recent years, the efficacy of nasal mask ventilation has been demonstrated in the treatment of chronic restrictive respiratory failure, particularly in patients with neuromuscular diseases. More recently, this method has been successfully used in the treatment of acute respiratory failure due to parenchymal disease. Method : We assessed the efficacy of Bilevel positive airway pressure(BiPAP) in the treatment of acute exacerbation of chronic obstructive pulmonary disease(COPD). This study prospectively evaluated the clinical effectiveness of a treatment schedule with positive pressure ventilation via nasal mask(Respironics BiPAP device) in 22 patients with acute exacerbations of COPD. Eleven patients with acute exacerbations of COPD were treated with nasal pressure support ventilation delivered via a nasal ventilatory support system plus standard treatment for 3 consecutive days. An additional 11 control patients were treated only with standard treatment. The standard treatment consisted of medical and oxygen therapy. The nasal BiPAP was delivered by a pressure support ventilator in spontaneous timed mode and at an inspiratory positive airway pressure $6-8cmH_2O$ and an expiratory positive airway pressure $3-4cmH_2O$. Patients were evaluated with physical examination(respiratory rate), modified Borg scale and arterial blood gas before and after the acute therapeutic intervention. Results : Pretreatment and after 3 days of treatment, mean $PaO_2$ was 56.3mmHg and 79.1mmHg (p<0.05) in BiPAP group and 56.9mmHg and 70.2mmHg (p<0.05) in conventional treatment (CT) group and $PaCO_2$ was 63.9mmHg and 56.9mmHg (p<0.05) in BiPAP group and 53mmHg and 52.8mmHg in CT group respectively. pH was 7.36 and 7.41 (p<0.05) in BiPAP group and 7.37 and 7.38 in cr group respectively. Pretreatment and after treatment, mean respiratory rate was 28 and 23 beats/min in BiPAP group and 25 and 20 beats/min in CT group respectively. Borg scale was 7.6 and 4.7 in BiPAP group and 6.4 and 3.8 in CT group respectively. There were significant differences between the two groups in changes of mean $PaO_2$, $PaCO_2$ and pH respectively. Conclusion: We conclude that short-term nasal pressure-support ventilation delivered via nasal BiPAP in the treatment of acute exacerbation of COPD, is an efficient mode of assisted ventilation for improving blood gas values and dyspnea sensation and may reduce the need for endotracheal intubation with mechanical ventilation.

• Journal of Yeungnam Medical Science
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• v.16 no.2
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• pp.333-341
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• 1999

Background and Methods: In order to evaluate characteristics and modulatory factors of blood pressure in peritoneal dialysis(PD), studies were conducted on the 69 patients who had underwent peritoneal equilibration test(PET). Results: The results were as follows; 1) All patients received an antihypertensive drug before PD, but, 15 of 69 patients successfully quit taking the antihypertensive drug after peritoneal dialysis. 2) During peritoneal dialysis, mean arterial pressure(MAP) was significantly decreased for the first 3 months, and this lasted for 1 year, and antihypertensive drug requirements were significantly decreased continuously up to 9 months(p<0.05). 3) After changing the modality from hemodialysis to peritoneal dialysis, MAP(mmHg, from $107.0{\pm}4.5$ to $98.6{\pm}8.8$, p<0.05), antihypertensive drug requirements(from $5.6{\pm}2.6$, to $2.0{\pm}2.5$, p<0.01) and erythropoietin dosages(Uint/week, from $4600{\pm}2660$ to $2000{\pm}1630$, p<0.05) were decreased. 4) Multiple logistic regression analysis showed that MAP(p<0.01) and daily ultrafiltration volume(p<0.05) can contribute to the determination of antihypertensive drug requirements. However the relationship between antihypertensive drug requirements and PET results or dialysis adequacy indices(weekly Kt/V, weekly creatinine clearance) was not revealed. Conclusion: In conclusion, the prescription of antihypertensive drugs should be considered according to daily ultrafiltration volume, especially during first year after initiating PD, and follow-ups for over a year may be needed.

• Journal of Trauma and Injury
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• v.25 no.1
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• pp.1-6
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• 2012

Purpose: This study analyzed the characteristics of unstable pelvic bone fractures associated with intra-abdominal solid organ injury. Methods: Medical records were retrospectively collected from January 2000 to December 2010 for patients with unstable pelvic bone fractures. Unstable pelvic bone fracture was defined as lateral compression types II and III, antero-posterior compression types II and III, vertical shear and combined type by young classification. Subjects were divided into two groups, with (injured group) and without (non-injured group) intra-abdominal solid organ injury, to evaluate whether the characteristics of the fractured depended on the presence of associated solid organ injury. Data included demographics, mechanism of injury, initial hemodynamic status, laboratory results, revised trauma score (RTS), abbreviated injury scale (AIS), injury severity score (ISS), amount of transfusion, admission to the intensive care unit (ICU), and mortality. Results: The subjects were 217 patients with a mean age of 44 years and included 134 male patients(61.8%). The injured group included 38 patients(16.9%). Traffic accidents were the most common mechanism of injury, and lateral compression was the most common type of fracture in all groups. The initial blood pressure was lower in the injured group, and the ISS was greater. The arterial pH was lower in the injured group, and shock within 24 hours after arrival at the emergency department was more frequent in the injured group. The amount of the transfused packed red blood cells within 24 hours was higher in the injured group than the non-injured group. Invasive treatment, including surgery and angiographic embolization, was more common in the injured group, and the stay in the ICU was longer in the injured group. Conclusion: A need exists to decide on a diagnostic and therapeutic plan regarding the possibility of intra-abdominal solid organ injury for hemodynamically unstable patients with unstable pelvic bone fractures and multiple associated injuries.

• Journal of Trauma and Injury
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• v.23 no.2
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• pp.57-62
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• 2010

Purpose: This study analyzed the characteristics of stable pelvic bone fractures with intra-abdominal solid organ injury. Methods: Medical records were retrospectively reviewed from January 2000 to December 2009 of patients with stable pelvic bone fractures. A stable pelvic bone fracture according to Young's classification is defined as a lateral compression type I and antero-posterior compression type I. Subjects were divided into two groups, one with (injured group) and one without (non-injured group) intra-abdominal solid organ injury, to evaluate the dependences of the characteristics on the presence of an intra-abdominal solid organ injury. Data including demographics, mechanism of injury, initial hemodynamic status, laboratory results, Revised Trauma Score (RTS), Abbreviated Injury Scale (AIS), Injury Severity Score (ISS), amount of transfusion, admission to intensive care unit (ICU), and mortality were analyzed. Results: The subjects were 128 patients with a mean age of 42 years old, of whom were 67 male patients (52.3%). The injured group had 21 patients(16.4%), and the most frequent injured solid organ was the liver. Traffic accident was the most common mechanism of injury and lateral compression was the most common type of fracture in all groups. Initial systolic blood pressure was lower in the injured group, and the ISS was greater in the injured group. Arterial pH was lower in the injured group, and shock within 24 hours after arrival at the emergency department was more frequent in the injured group. Transfused packed red blood cells within 24 hours were 8 patients(38.1%) in the injured group and 11 patients(10.3%) in the non-injured group. Conservative treatment was the most common therapeutic modality in all groups. Stay in the ICU was longer in the injured group, and three mortalities occurred. Conclusion: There is a need to decide on a diagnostic and therapeutic plan regarding the possibility of intra-abdominal solid organ injury for hemodynamically unstable patients with stable pelvic bone fractures and for patients with stable pelvic bone fractures along with multiple associated injuries.

• The Korean Journal of Physiology
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• v.27 no.1
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• pp.67-77
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• 1993

Acute and chronic effects of ethanol (EOH) administration on the cardiovascular and hormonal responses to repeated hemorrhage were investigated in conscious normotensive Wistar rats and spontaneously hypertensive rats (SHR). The chronic EOH treated group received 5% EOH (vol/vol) ad libitum in the drinking water far the first week,10% for the last 2 weeks, and 20% for the last 5 weeks from the age of 6 weeks. The EOH free group received tap water. Chronic EOH and EOH free groups were randomly subdivided into acute EOH infusion and control groups. Under ether anesthesia, catheters were inserted into the femoral vein and both femoral arteries. After rats regained consciousness and their blood pressure was stabilized, responses to quick hemorrhage (5 ml/kg BW) were tested. In the acute EOH infusion group, hemorrhage was induced 20 min after EOH infusion (1.0 g/kg BW), Baroreceptor reflex sensitivity was assessed by the ratio of changes in hen.1 rate and mean arterial pressure (${\Delta}HR/{\Delta}MAP$) immediately after the hemorrhage. Chronic EOH administration elevated MAP in Wistar rats. During acute EOH infusion, MAP do- creased and HR increased in all groups. In comparison to EOH free control rats, acute or chronic EOH treated rats showed a greater reduction in MAP and a smaller elevation in heart rate in response to a hemorrhage. The degree of MAP reduction was significantly greater in SHR than in Wistar rats. Both the acute and chronic EOH administration attenuated the baroreceptor reflex and retarded MAP recovery, again the trend being much more prominent in SHR. The increase in plasma vasopressin and lenin concentrations after hemorrhage were intensified by the chronic EOH administration. SHR showed a greater vasopressin response but a smaller lenin response than Wistar rats. These results indicate that the EOH treated rats, particularly SHB, are prone to shock by a hemorrhage, which may be partly attributed to an impaired baroreceptor reflex function.

• The Korean Journal of Pain
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• v.14 no.2
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• pp.181-185
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• 2001

Background: Bradycardia frequently occurs in intravenous anesthesia with propofol. Additionally, the thoracic sympathetic nerves influence the heart so that the heart rate (HR) and blood pressure are expected to decrease due to this procedure. Therefore, we measured changes in HR, mean arterial pressure (MAP) and both thumb temperatures before and after thoracic sympathicotomy under total intravenous anesthesia with propofol. Methods: The subjects included 21 outpatients of ASA class I who received thoracoscopic thoracic sympathicotomy under total intravenous anesthesia. Anesthesia was induced with propofol (2 mg/kg) and vecuronium (0.1 mg/kg) and maintained with propofol-fentanyl-oxygen (100%). The surgical procedure was performed at the T3 level in the order of left sympathicotomy (LST) and right sympathicotomy (RST). Measurements of HR, MAP and both thumb temperatures were taken before induction of anesthesia, before and after LST and RST, and 1 hour after the completion of anesthesia. Additionally, the time to the beginning of a rise in temperature in both thumbs after sympathicotomy was recorded. Results: HR did not show any significant difference before or after sympathicotomy, however it decreased at 1 hour after the completion of anesthesia. MAP decreased after LST and decreased further after RST. Left thumb temperature began to increase at $45.8{\pm}10.7$ seconds after LST. Right thumb temperature initially decreased after LST and increased from $45.2{\pm}11.8$ seconds after RST. Subsequently, both increased temperatures were maintained at 1 hour after the completion of anesthesia. Conclusions: Although HR and MAP decreased, there were no severe hemodynamic changes. An increase in the thumb temperature was confirmed within 1 minute after sympathicotomy on the same side.

• Korean Journal of Acupuncture
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• v.21 no.1
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• pp.1-14
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• 2004

Objectives : This research was performed to investigate the effect of acupuncture at the $KI_2\;KI_{10}\;HT_8\;HT_3$, on Aquaporin-2(AQP2) expression related with the renal functions in rats. Methods : Acupuncture was performed during 100-seconds, 6-times, at 150-seconds intervals under anesthesia in rats. We observed rats' mean arterial pressure(MAP), heart rate(HR), renal sympathetic nerve activity(RSNA) during acupuncture and AQP2 expression by western blot method and atrial natriuretic peptide(ANP), renin, norepinephrine of plasma after decapitation. Results : The AQP2 expression was significantly increased in $HT_8$ group, but decreased in $KI_{10}$ group. Average MAP during 6-times acupuncture was significantly increased in $HT_8$ group. Average HR was significantly increased in $HT_8$ group, Average RSNA was increased in $KI_{10}$ group, but that was marginally increased in $KI_{10}$ group. Plasma renin concentration was increased in $KI_2,\;HT_3$, groups. Plasma ANP show a tendency to decrease in $KI_10\;HT_3$ groups, increased in $KI_2,\;HT_3$ but not significant. Plasma norepinephrine concentration was significantly decreased in $KI_{10},\;HT_3$ groups. Conclusions : These results suggested that acupuncture at $HT_8$ activate renal function to reuptake, but $KI_{10}$ show a decline on effect of AQP2 expression, blood pressure, nerve activity and renin.

• The Korean Journal of Physiology
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• v.28 no.2
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• pp.133-141
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• 1994

The discharge patterns and peripheral nerve inputs to cardiovascular neurons were investigated in rostral ventrolateral medulla (RVLM) and raphe nucleus of cats. The data from the two were compared to determine their roles in cardiovascular regulation and the endogenous analgesic system. Animals were anesthetized with ${\alpha}-chloralose$ and single cell activities were recorded by carbon-filament microelectrode and their relationships with cardiovascular activity were analyzed. In RVLM area, a total of thirty-three cells were identified as cardiovascular neurons. During one cardiac cycle, the mean discharge rate of the neurons was $1.96{\pm}0.29$ and the peak activity was observed 45 ms after the systolic peak of arterial blood pressure. Thirteen cells could be activated antidromically by stimulation of the the $T_2$ intermediolateral nucleus. Forty-three raphe neurons were identified as cardiovascular neurons whose mean discharge rate during one cardiac cycle was $1.02{\pm}0.12$. None of these cells could be activated antidromically. Study of the interval time histogram of RVLM neurons revealed that the time to the first peak was $128{\pm}20.0\;ms$, being shorter than the period of a cardiac cycle. The same parameter found from the raphe neurons was $481{\pm}67.2\;ms$, which was much longer than the cardiac cycle length. Of seventeen RVLM neurons examined ten received only the peripheral $A{\delta}-afferent$ inputs, whereas six RVLM neurons received both $A{\delta}-$ and C-inputs; the remaining one cell received an inhibitory peripheral C-input. In contrast, nine of eleven raphe neurons were found to receive $A{\delta}-inputs$ only. We conclude that the main output of cardiovascular regulatory influences are mediated through the RVLM neurons. The cardiovascular neurons in the raphe nucleus appear to serve as interneurons transferring cardiovascular afferent information to the raphespinal neurons mediating the endogenous analgesic mechanisms.

• Journal of Chest Surgery
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• v.39 no.12 s.269
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• pp.879-890
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• 2006

Background: The dysfunction of multiple organs is found to be caused by reactive oxygen species as a major modulator of microvascular injury after hemorrhagic shock. Hemorrhagic shock, one of many causes inducing acute lung injury, is associated with increase in alveolocapillary permeability and characterized by edema, neutrophil infiltration, and hemorrhage in the interstitial and alveolar space. Aggressive and rapid fluid resuscitation potentially might increased the risk of pulmonary dysfunction by the interstitial edema. Therefore, in order to improve the pulmonary dysfunction induced by hemorrhagic shock, the present study was attempted to investigate how to reduce the inflammatory responses and edema in lung. Material and Method: Male Sprague-Dawley rats, weight 300 to 350 gm were anesthetized with ketamine(7 mg/kg) intramuscular Hemorrhagic Shock(HS) was induced by withdrawal of 3 mL/100 g over 10 min. through right jugular vein. Mean arterial pressure was then maintained at $35{\sim}40$ mmHg by further blood withdrawal. At 60 min. after HS, the shed blood and Ringer's solution or 5% albumin was infused to restore mean carotid arterial pressure over 80 mmHg. Rats were divided into three groups according to rectal temperature level($37^{\circ}C$[normothermia] vs $33^{\circ}C$[mild hypothermia]) and resuscitation fluid(lactate Ringer's solution vs 5% albumin solution). Group I consisted of rats with the normothermia and lactate Ringer's solution infusion. Group II consisted of rats with the systemic hypothermia and lactate Ringer's solution infusion. Group III consisted of rats with the systemic hypothermia and 5% albumin solution infusion. Hemodynamic parameters(heart rate, mean carotid arterial pressure), metabolism, and pulmonary tissue damage were observed for 4 hours. Result: In all experimental groups including 6 rats in group I, totally 26 rats were alive in 3rd stage. However, bleeding volume of group I in first stage was $3.2{\pm}0.5$ mL/100 g less than those of group II($3.9{\pm}0.8$ mL/100 g) and group III($4.1{\pm}0.7$ mL/100 g). Fluid volume infused in 2nd stage was $28.6{\pm}6.0$ mL(group I), $20.6{\pm}4.0$ mL(group II) and $14.7{\pm}2.7$ mL(group III), retrospectively in which there was statistically a significance between all groups(p<0.05). Plasma potassium level was markedly elevated in comparison with other groups(II and III), whereas glucose level was obviously reduced in 2nd stage of group I. Level of interleukine-8 in group I was obviously higher than that of group II or III(p<0.05). They were $1.834{\pm}437$ pg/mL(group I), $1,006{\pm}532$ pg/mL(group II), and $764{\pm}302$ pg/mL(group III), retrospectively. In histologic score, the score of group III($1.6{\pm}0.6$) was significantly lower than that of group I($2.8{\pm}1.2$)(p<0.05). Conclusion: In pressure-controlled hemorrhagic shock model, it is suggested that hypothermia might inhibit the direct damage of ischemic tissue through reduction of basic metabolic rate in shock state compared to normothermia. It seems that hypothermia should be benefit to recovery pulmonary function by reducing replaced fluid volume, inhibiting anti-inflammatory agent(IL-8) and leukocyte infiltration in state of ischemia-reperfusion injury. However, if is considered that other changes in pulmonary damage and inflammatory responses might induce by not only kinds of fluid solutions but also hypothermia, and that the detailed evaluation should be study.