Effects of Intravenous Verapamil on Hemodynamics and Pulmonary Gas Exchanges in Isoflurane-N2O-O2 Anesthetized Man / 대한마취과학회지

The purpose of this study was to evaluate the effects of verapamil on hemodynamics and pulmonary gas exchanges during isoflurane-N2O-O2(FIO2, 50%) anesthesia. Hemodynamic measurements and arterial and mixed venous blood gas analyses were made in thirteen healthy patients immediately before (control) and at 1, 5,10min after 5mg of intravenous verapamil administration as single bolus. 1) Verapamil produced a rapid and transient reduction of 15% in mean arterial pressure resulting from a decrease in systemic vascular resistance. 2) Heart rate and cardiac index increased by 14%, 9% respectively only immediately after i.v. verapamil injection and restored thereafter toward control values. 3) SVI, MPAP, PCWP, PVR and CVP revealed only minor changes. 4) Verapamil did not cause any significant changes in intrapulmonary shunt. These findings suggest that during isoflurane-N2O-O2(50%) anesthesia verapamil might safely be used, even in the presence of ventilation/perfusion inequalities, (i.e. lung disease, one lung anesthesia) provided patient has good cardiovascular reserve.

The Effects of Propranolol on Hemodynamic Responaea and Intrapulmonary Shunting during Induced Hypotension with Sodium Nitroprussid in Pstiente Aneethetized with Halothane and Nitrous Oxide / 대한마취과학회지

Sodium nitroprusside hart become increasingly popular as a vasodilator due to its high potency, rapid onset and reversibility. However, it has some untoward effects including cyanide toxicity, tachyphylaxis, and rebound phenomenon. Accordingly, several attempts to dimmish such complications have been tried including the use propranolol, a possible direct cardiovascular depressant. Therefore, to determine whether propranolol makes a deleterious contribution to hemodynamic responses and impaired in pulmonary gas exchange during SNP in patients anesthetized with halothane-N2O (FiO2; 0.5), experiments were performed on 25 patients with deliberate hypotension scheduled for elective surgery. Thirteen patients were pretreated with divided doses of propranolo (320mg, b.i.d po) and the other twelve were controls. The results were as follows. 1) Cardiac index was significantly lower in pretreated with propranolol than the untreated control in the hypotensive period (3.45+/-0.16 vs 2.97+/-7.141/min/m2, p<0.05). 2) Heart rate increased by 20% in control group during the hypotensive period, but it remained unaltered in propranolol group at all times. 3) Hypotension induced by SNP, resulted from a marked decrease in systemic vascular resistance in both groups. 4) MPAP, PCWP, CVP, SVR, PVR significantly decreased after SNP infusion in both groups, but , they did not differ significantly between the groups at all times. 5) SNP caused a significant increase in intrapulmonary shunt fraction from 8.26+/-0.51 to 10.11+/-0.92%, but propranolo prevented it. 6) Mixed venous oxygen tension was significantly lower in propranolol group than in untreated control group at all times. 7) Patients who .received propranolo required less SNP than the untreated control. (2.51+/-0.22 vs 5.95+/-0.75 mcg/kg/min, p<0.001) These results indicate that propranolol required does not produce any unfavorable hemodynamic event and, furthermore, prevents impairment of pulmonary gas exchange during SNP induced hypotension in patients anesthetized with halothane and nitrous oxide. Therefore, premfdication with propranolol should be considered for patients who are supposed to receive SNP for deliberate hypotension.

The Effects of Propranolol on Hemodynamic Responaea and Intrapulmonary Shunting during Induced Hypotension with Sodium Nitroprussid in Pstiente Aneethetized with Halothane and Nitrous Oxide / 대한마취과학회지

Sodium nitroprusside hart become increasingly popular as a vasodilator due to its high potency, rapid onset and reversibility. However, it has some untoward effects including cyanide toxicity, tachyphylaxis, and rebound phenomenon. Accordingly, several attempts to dimmish such complications have been tried including the use propranolol, a possible direct cardiovascular depressant. Therefore, to determine whether propranolol makes a deleterious contribution to hemodynamic responses and impaired in pulmonary gas exchange during SNP in patients anesthetized with halothane-N2O (FiO2; 0.5), experiments were performed on 25 patients with deliberate hypotension scheduled for elective surgery. Thirteen patients were pretreated with divided doses of propranolo (320mg, b.i.d po) and the other twelve were controls. The results were as follows. 1) Cardiac index was significantly lower in pretreated with propranolol than the untreated control in the hypotensive period (3.45+/-0.16 vs 2.97+/-7.141/min/m2, p<0.05). 2) Heart rate increased by 20% in control group during the hypotensive period, but it remained unaltered in propranolol group at all times. 3) Hypotension induced by SNP, resulted from a marked decrease in systemic vascular resistance in both groups. 4) MPAP, PCWP, CVP, SVR, PVR significantly decreased after SNP infusion in both groups, but , they did not differ significantly between the groups at all times. 5) SNP caused a significant increase in intrapulmonary shunt fraction from 8.26+/-0.51 to 10.11+/-0.92%, but propranolo prevented it. 6) Mixed venous oxygen tension was significantly lower in propranolol group than in untreated control group at all times. 7) Patients who .received propranolo required less SNP than the untreated control. (2.51+/-0.22 vs 5.95+/-0.75 mcg/kg/min, p<0.001) These results indicate that propranolol required does not produce any unfavorable hemodynamic event and, furthermore, prevents impairment of pulmonary gas exchange during SNP induced hypotension in patients anesthetized with halothane and nitrous oxide. Therefore, premfdication with propranolol should be considered for patients who are supposed to receive SNP for deliberate hypotension.

Effect of Lidocaine, Propranolol and Droperidol Pretreatment on Ephedrine Induced Arrhythmia During Halothane-N2O Anesthesia / 대한마취과학회지

Halothane, in common use today, sensitizes the myocardium to endogenous and exogenous sympathomimetic amines arid induces cardiac arrhythmia, sometimes life threatening. Sympatbomimetic amines, however, are frequently injected subcutaneously for hemostasis or intravenously far cardiovascular stability. Therefore, this study was performed to investigate the effect of lidocaine 1 mg/kg, pro-pranolol 0.02 mg/kg, and droperidol 0.1 mg/kg pretreatment on arrhythmias(A.R.) and changes in heart ramie(H.R.), systolic bood pressure(T.B.P ) and diastolic blood pressure (D.B.P.) Induced by lV administered ephedrine 0.2 mg/kg. Patients were divided into 5 groups: 20 cases without pretreatment(Group l ), 10 cases with lidocaine prtreatment(Group ll), 10 cases with propranolol pretreatment(Group lll), 20 eases with lidocaine-propranolol pretreatment(Group lV) and 20 cases with droperidol pretreatment(Group V ). The results were as follows: 1) In Group l, ephedrine produced A.R. in 16 cases(80%) and significant increase in H.R.(d~11 bpm, p<0.001) and S.B.P. (8~22 torr, p<0.001), but D.B.P. increased insignif-icantly(2~10 torr, NS). 2) In Group ll, ephedrine produced A.R. in 5 cases(57%) and 5.B.p.(10~17 terr, p<0, 01) increased significantly, but H.R. remained unaltered. 3) In Group lll, ephedrine produced A.R. in 3 cases(30%) and H.R. (6~8 bpm, p<0.05) decreased, but S.B.P.(12~21 torr, p<0.01) and D.B.P (8~16 torr, p<0.01) increased signi-ficantle. 4) In Group lV, ephedrine produced A.R. in 2 cases(10.%) and H.R.(3~6 bpm, p<0.05) decreased, but S.B.P (4~11 torr, p<0.05) and D.B.P.(3~9 torr, p<0.01) increased signific-antly. 5) In Group V. ephedrine produced A.R. in 2 cases(10%) and H.R.(9~13 bum, p<0.001) increased siginificantly, but S.B.P. and D.B.P. remained unaltered. From the above results, it is concluded that lidocaine and propranolol mixture or droperidol protects most effectively against ventricular arrhythmias induced by ephedrine during halothane-N2O anesthesia in human volunteers.