Terlipressin versus norepinephrine to correct refractory arterial hypotension after general anesthesia in patients chronically treated with renin-angiotensin system inhibitors

BACKGROUND: Terlipressin, a precursor that is metabolized to lysine-vasopressin, has been proposed as a drug for treatment of intraoperative arterial hypotension refractory to ephedrine in patients who have received long-term treatment with renin-angiotensin system inhibitors. The authors compared the effectiveness of terlipressin and norepinephrine to correct hypotension in these patients. METHODS: Among 42 patients scheduled for elective carotid endarterectomy, 20 had arterial hypotension following general anesthesia that was refractory to ephedrine. These patients were the basis of the study. After randomization, they received either 1 mg intravenous terlipressin (n = 10) or norepinephrine infusion (n = 10). Beat-by-beat recordings of systolic arterial blood pressure and heart rate were stored on a computer. The intraoperative maximum and minimum values of blood pressure and heart rate, and the time spent with systolic arterial blood pressure below 90 mmHg and above 160 mmHg, were used as indices of hemodynamic stability. Data are expressed as median (95% confidence interval). RESULTS: Terlipressin and norepinephrine corrected arterial hypotension in all cases. However, time spent with systolic arterial blood pressure below 90 mmHg was less in the terlipressin group (0 s [0-120 s] vs. 510 s [120-1011 s]; P < 0.001). Nonresponse to treatment (defined as three boluses of terlipressin or three changes in norepinephrine infusion) occurred in zero and eight cases (P < 0.05), respectively. CONCLUSIONS: In patients who received long-term treatment with renin-angiotensin system inhibitors, intraoperative refractory arterial hypotension was corrected with both terlipressin and norepinephrine. However, terlipressin was more rapidly effective for maintaining normal systolic arterial blood pressure during general anesthesia.     

Terlipressin versus norepinephrine to counteract intraoperative paracentesis induced refractory hypotension in cirrhotic patients

Back groundSome of tense ascitic patients with end stage liver disease and portal hypertension were presented to our emergency department with surgical acute abdomen that required urgent abdominal surgery which might be associated with inevitable rapid and relatively complete evacuation of this ascitic fluid with possible occurrence of post-paracentesis-induced hypotension. The aims of this study were to compare between the intraoperative use of terlipressin versus norepinephrine for the management of paracentesis induced refractory hypotension not responding to colloid resuscitation or ephedrine in patients with end-stage liver disease during emergency abdominal surgery.Patients and methodThirty-four patients experienced refractory hypotension during or shortly after the paracentesis process were randomized to receive either bolus dose of terlipressin (1 mg over 30 min) followed immediately by a continuous infusion of 2 μg/kg/h (T group, n = 17) or norepinephrine infusion at starting dose of 0.1 μg/kg/min (N group, n = 17).MeasurementsHemodynamic parameters, cardiac output, systemic vascular resistance, blood gases, lactic acid, liver and kidney functions.ResultsAll patients of both groups showed significant decreases in MAP during or immediately after the paracentesis process to reach mean values of 57 ± 1.4 and 58 ± 1.8 mmHg in terlipressin or norepinephrine groups respectively. This was associated with drop in the SVR that reached mean values of 445 ± 28 and 425 ± 20 dynes/sec/cm⁵ in both terlipressin and norepinephrine groups respectively. At the 2nd day post operative there was significant increase in serum creatinine values in the norepinephrine group.ConclusionTerlipressin and norepinephrine successfully counteracted the post-paracentesis refractory hypotension and the drop of the systemic vascular resistance. It also showed the renal protective effects of terlipressin in the immediate postoperative period.     

Influence of nifedipine on systemic and regional hemodynamics during adenosine-induced hypotension in dogs

Previous pharmacologic studies indicating competitive interactions between adenosine and nifedipine at the adenosine vascular receptor suggest that adenosine may be a less effective hypotensive drug after pretreatment with nifedipine. This hypothesis was tested in 18 pentobarbital-anesthetized, open-chest dogs by evaluating the hypotensive effects and regional hemodynamic responses to 60-minute intravenous adenosine infusions before and after bolus injection of nifedipine (20 micrograms/kg, IV). Regional blood flow was measured with 15-microns radioactive microspheres. Before nifedipine, infusion of adenosine at a rate of 126 +/- 30 mumol/min caused a 50% reduction in mean aortic pressure that in the presence of no change in aortic blood flow was attributable to a proportional decrease in systemic vascular resistance. These systemic effects were associated with heterogeneous changes in regional blood flow; blood flow decreased in the renal cortex (-68%), pancreas (-50%), spleen (-77%), and skin (-61%); increased in the left (+112%) and right (+265%) ventricular myocardium; and did not change significantly in the duodenum, liver, skeletal muscle, or brain. Nifedipine did not alter the dose requirement or time course of the adenosine-induced hypotensive response or affect the associated systemic hemodynamic changes. Furthermore, nifedipine caused only minor alterations in the regional blood flow changes during adenosine-induced hypotension. Apparently the high plasma levels of adenosine required for controlled hypotension in the present study were sufficient to overcome the blocking influence of nifedipine at the adenosine vascular receptor. The study demonstrates that the hypotensive action of adenosine remains unimpaired after pretreatment with nifedipine.(ABSTRACT TRUNCATED AT 250 WORDS)     

Treatment of intraoperative refractory hypotension with terlipressin in patients chronically treated with an antagonist of the renin-angiotensin system.

The goal of the present study was to determine whether terlipressin, an agonist of the vasopressin system, could counteract perioperative hypotension refractory to common vasopressor therapy and to analyze its circulatory effects. We enrolled 51 consecutive vascular surgical patients chronically treated with angiotensin-converting enzyme inhibitors or antagonists of the receptor of angiotensin II, who received a standardized opioid-propofol anesthetic. Of these 51 patients, 32 had at least one episode of hypotension, which responded to epinephrine or phenylephrine. In 10 other patients, systolic arterial pressure (SAP) did not remain above 100 mm Hg for 1 min, despite three bolus doses of ephedrine or phenylephrine. In these patients, we injected a bolus of 1 mg of terlipressin, repeated twice if necessary. Hemodynamic and echocardiographic variables were recorded every 30 s over 6 min. In eight patients, arterial pressure was restored with one injection of terlipressin; in two other patients, three injections were necessary. One minute after the last injection of terlipressin, the SAP increased from 88+/-3 to 100+/-4 mm Hg and reached 117+/-5 mm Hg (P = 0.001) 3 min after the injection and remained stable around this value. This increase in SAP was associated with significant changes in left ventricular end-diastolic area (17.9+/-2 vs 20.2+/-2.2 cm2; P = 0.003), end-systolic area (8.1+/-1.3 vs 9.6+/-1.5 cm2; P = 0.004), end-systolic wall stress (45+/-8 vs 66+/-12; P = 0.001), and heart rate (60+/-4 vs 55+/-3 bpm; P = 0.001). Fractional area change and velocity of fiber shortening did not change significantly. No additional injection of vasopressor was required during the perioperative period. No change in ST segment was observed after the injection. IMPLICATIONS: Terlipressin is effective to rapidly correct refractory hypotension in patients chronically treated with antagonists of the renin-angiotensin system without impairing left ventricular function.     

Glomerular hemodynamics and the renin-angiotensin system in patients with type 1 diabetes mellitus

BACKGROUND: Many studies have reported that blocking the renin-angiotensin-system (RAS) with an angiotensin-converting enzyme (ACE) inhibitor or an angiotensin receptor blocker in the patient with diabetes mellitus leads to an increase in renal plasma flow (RPF), no change in glomerular filtration rate (GFR), and a fall in filtration fraction. This constellation is generally attributed to predominant efferent arteriolar dilation. METHODS: This study examined the renal hemodynamic response to blocking the RAS with both captopril and candesartan on separate days in 31 patients with type 1 diabetes mellitus. RESULTS: There was a wide range of changes in RPF and GFR in response to the two agents, each administered at the top of its dose-response range. The RPF response to the two agents was strongly concordant (r = 0.65; P < 0.001), as was the GFR response (r = 0.81; P < 0.001). Moreover, there was a strong correlation between the RPF response and the change in GFR with each agent (r = 0.83 and 0.66; P < 0.01). A significant rise in RPF was followed by a rise in GFR. The RPF dependency of GFR in the type 1 diabetics suggests strongly that glomerular filtration equilibrium exists in the glomeruli of the diabetic kidney: Simple notions of local control based on afferent:efferent arteriolar resistance ratios are too simplistic. CONCLUSION: Our data suggest that the intrarenal RAS is activated in over 80% of patients with type 1 diabetes mellitus. Abundant evidence suggests that this activation predisposes to diabetic nephropathy.     

降钙素基因相关肽控制性降压对大鼠血流动力学和器官血流的影响

目的：人α－降钙素基因相关肽（α－ｈＣＧＲＰ）是从人体内提出的具有强效降压作用的多肽，无毒性。方法：静注ＣＧＲＰ和硝普钠使大鼠平均动脉压降为６．７ｋＰａ，维持１小时。用放射性同位素技术测定心输出量和器官血流量。结果：ＣＧＲＰ降压明显增加心输出量及心肌肝肾和脑组织血流量，并降低外周血管阻力及增快心率。停药３０分钟后无反跳性高血压出现。硝普钠降压则使心输出量及肝肾和脑组织血流量明显下降，心肌血流量增加，心率增快。结论：ＣＧＲＰ应用于控制性降压具有降压迅速，易于调控，增加心输出量和重要器官血流量及无反跳性高血压的特点，因而优于硝普钠。     

Effects of diadenosine tetraphosphate on systemic and regional hemodynamics in dogs

Purpose. Diadenosine tetraphosphate (AP₄A) produces vasodilation and hypotension. If AP₄A is to be employed clinically, its influence on systemic and regional hemodynamics needs to be investigated. In this study, we observed systemic and regional hemodynamics during reduction of mean arterial pressure (MAP) induced by AP₄A in dogs. Methods. Nineteen mongrel dogs were allocated to three groups: those given physiological saline (vehicle group) and dogs in which MAP was decreased either by 8% (8% group) or by 30% (30% group) by infusion of AP₄A. Systemic hemodynamics and microsphere-determined regional blood flow to vital organs were assessed before and during AP₄A infusion. Results. In the 8% group, cardiac output (CO) increased, and systemic vascular resistance (SVR) decreased during AP₄A infusion. Although regional blood flow to myocardium and portal organs increased, hepatic blood flow decreased. In the 30% group, heart rate and SVR decreased, and stroke volume index increased without change in CO. Regional blood flow to myocardium, kidneys, and portal organs increased. In both groups, cerebral blood flow remained unchanged. Conclusion. During the decrease in MAP induced by AP₄A, there were increases in regional blood flow distributed to the myocardium, kidneys, and portal organs, without change in the blood supply to the brain. This finding suggests that AP₄A may be clinically useful for reducing blood pressure without compromising blood flow to vital organs. Received for publication on January 26, 1998; accepted on September 18, 1998     

Short-term versus prolonged systemic antibiotic prophylaxis in patients treated with indwelling catheters

Newly hospitalized patients with stroke treated by indwelling catheters were assigned randomly to 3 treatment groups. Group 1 (24 patients) received 3 gm. ampicillin intramuscularly in divided doses 1 hour before, at the time of and 6 hours after insertion of the catheter. Group 2 (28 patients) received daily 1 gm. ampicillin intramuscularly every 8 hours. Group 3 (26 patients) was not subjected to any antimicrobial prophylaxis. Within 1 week after catheter insertion significant bacteriuria developed in 12.5 per cent of the patients in group 1, 42.8 per cent in group 2 and 45.1 per cent in group 3. The difference in the incidence between group 1 and either group 2 or 3 was statistically significant (p less than 0.02 and p less than 0.01, respectively). The mean number of strains (plus or minus standard error of mean) isolated per case of bacteriuria in group 3 (1.25 plus or minus 0.18) was significantly lower (p less than 0.05) and antimicrobial resistant strains were fewer (4 of 15) than in group 2 (1.75 plus or minus 0.13 and 12 of 21, respectively).     

Spinal anesthesia-induced hypotension: a risk comparison between patients with severe preeclampsia and healthy women undergoing preterm cesarean delivery

We previously showed that, in comparison with term healthy parturients, patients with severe preeclampsia had a less frequent incidence of spinal hypotension, which was less severe and required less ephedrine. In the present study, we hypothesized that these findings were attributable to preeclampsia-associated factors rather than to a smaller uterine mass. The incidence and severity of hypotension were compared between severe preeclamptics (n = 65) and parturients with preterm pregnancies (n = 71), undergoing spinal anesthesia for cesarean delivery (0.5% bupivacaine, sufentanil, morphine). Hypotension was defined as the need for ephedrine (systolic blood pressure <100 mm Hg in parturients with preterm fetuses or 30% decrease in mean blood pressure in both groups). Apgar scores and umbilical arterial blood pH were also studied. Neonatal and placental weights were similar between the groups. Hypotension was less frequent in preeclamptic patients than in women with preterm pregnancies (24.6% versus 40.8%, respectively, P = 0.044). Although the magnitude of the decrease in systolic, diastolic, and mean arterial blood pressure was similar between groups, preeclamptic patients required less ephedrine than women in the preterm group to restore blood pressure to baseline levels (9.8 +/- 4.6 mg versus 15.8 +/- 6.2 mg, respectively, P = 0.031). The risk of hypotension in the preeclamptic group was almost 2 times less than that in the preterm group (relative risk = 0.603; 95% confidence interval, 0.362-1.003; P = 0.044). The impact of Apgar scores was minor, and umbilical arterial blood pH was not affected. We conclude that preeclampsia-associated factors, rather than a smaller uterine mass, account for the infrequent incidence of spinal hypotension in preeclamptic patients.     

Terlipressin-ephedrine versus ephedrine to treat hypotension at the induction of anesthesia in patients chronically treated with angiotensin converting-enzyme inhibitors: a prospective, randomized, double-blinded, crossover study

In patients chronically treated with angiotensin converting-enzyme inhibitors (ACEI), typically selected doses of ephedrine do not always restore arterial blood pressure when anesthesia-induced hypotension occurs. We postulated that the administration of terlipressin, an agonist of the vasopressin system, with ephedrine more effectively restores pressure in this setting than the administration of ephedrine alone. This prospective, randomized, cross-over, double-blinded study compared terlipressin combined with ephedrine (n = 19) with ephedrine alone (n = 21) in treating hypotension at the induction of anesthesia in 40 ACEI-treated patients undergoing hypotension (mean arterial blood pressure [MAP] <65 mm Hg or <30% of baseline value) after standardized anesthetic protocol (target-controlled IV anesthesia with propofol). Data are mean +/- SD. Patient characteristics, MAP, and heart rate before and after the induction of anesthesia during hypotensive episodes were not significantly different between the two groups. After the first bolus, MAP was significantly greater in the Terlipressin-Ephedrine group (72 +/- 12 mm Hg versus 65 +/- 8 mm Hg, P < 0.05). The occurrence of a second hypotensive episode (5% versus 71%, P < 0.001), the duration (2 +/- 1 min versus 3 +/- 1 min, P < 0.01) of hypotensive episodes, and the median dose of ephedrine (3 versus 6 mg, P < 0.05) were significantly less in the Terlipressin-Ephedrine group. In conclusion, terlipressin combined with ephedrine is more effective than ephedrine alone for treating anesthesia-induced hypotension in ACEI-treated patients. We conclude that this patient population with a partially blocked endogenous response to hypotension may be good candidates for successful use of a vasopressin analog to counteract intraoperative refractory hypotension. IMPLICATIONS: Vascular surgical patients chronically treated with drugs that inhibit the functioning of the renin-angiotensin system may experience hypotension unresponsive to conventional therapy. This double-blinded, cross-over study demonstrated that in these patients the use of a vasopressin analog, terlipressin given with ephedrine, was effective in reversing intraoperative systemic hypotension refractory to ephedrine.     

中度急性高容量血液稀释联合控制性降压对颅内动脉瘤手术病人血流动力学和脑血流的影响

目的观察中度急性高容量血液稀释(AHH)联合应用控制性降压对颅内动脉瘤夹闭术病人血液动力学和局部脑血流(rCBF)的影响.方法19例颅内动脉瘤病人随机分为异氟醚组(A组,n=10)和尼莫地平组(B组,n＝9).诱导后两组均进行中度AHH(Hct= 25%～30%),监测血流动力学、颅内压(ICP)及动脉瘤跨壁压(TMP)的变化.降压期间,A组提高异氟醚吸入浓度至1.4～1.6MAC;B组尼莫地平5～8μg@kg-1静注,继以10～100μg@kg-1@h-1速率持续泵入,两组均维持MAP在8.0～8.7kPa.用激光多普勒血流仪(LDF)连续监测降压前(T0)、降压中(包括动脉瘤夹闭前T1、夹闭后T2)和升压后(T3)rCBF的变化.结果与AHH前比较,两组在AHH后Hb、Hct和CaO2均显著降低(P<0.01),MAP、CVP、HR、ICP及TMP均无显著性变化(P>0.05);两组在T0～T3期间rCBF和CaO2均无明显变化(P>0.05);T3时A组的HR快于B组(P<0.05).结论在颅内动脉瘤夹闭术中,实施中度AHH能保持血流动力学和TMP稳定,联合应用异氟醚或尼莫地乎控制性降压,不影响rCBF.     

The hemodynamic effects of intravenous norepinephrine versus epinephrine and phenylephrine in patients with ischemic heart disease

The hemodynamic effects of an intravenous bolus of norepinephrine 10 micrograms, phenylephrine 100 micrograms and epinephrine 10 micrograms were investigated in 30 patients scheduled for coronary artery bypass grafting. The hemodynamic changes following norepinephrine were similar to those achieved by phenylephrine. Both drugs increased the mean blood pressure and systemic vascular resistance without any significant change of cardiac output. In contrast, epinephrine increased the mean arterial pressure and cardiac output without a significant change of systemic vascular resistance. The results suggest that intravenous norepinephrine acts similar to phenylephrine as an alpha-adrenergic agonist, while epinephrine acts predominantly as a beta-adrenergic agonist.     

Long-term mortality benefit of renin-angiotensin system inhibitors in patients with chronic limb-threatening ischemia undergoing vascular intervention

Objective

The beneficial effect of renin-angiotensin system (RAS) inhibitors has been well-established in patients with cardiovascular disease; however, their effectiveness in patients with chronic limb-threatening ischemia (CLTI), a selected disease-burdened population, is largely unknown. The purpose of this study was to evaluate long-term outcomes of RAS inhibitor use in patients with CLTI undergoing a vascular intervention.

垂体后叶素对心肺转流后严重低血压患者血流动力学的影响

目的 观察垂体后叶素对心肺转流(CPB)停机后严重低血压患者血流动力学的影响.方法 110例行心内直视手术患者,CPB停机后发生严重低血压时,静脉给予垂体后叶素负荷量0.6U及维持量1～4 U/h.记录切皮前(T1)、CPB停机后注射垂体后叶素前(T2)、注射垂体后叶素后5min(T3)及术毕时(T4)MAP、HR、CVP、平均肺动脉压(MPAP)、体循环阻力(SVR)、心脏指数(CI)及每搏指数(SVI).结果 20例患者CPB停机后发生严重低血压.与T1时比较,T2时MAP及SVR显著降低(P＜0.01),HR增快(P＜0.01);与T2时比较,T3时MAP、SVR、CI及SVI显著升高(P＜0.05或P＜0.01),T4时MAP与SVR均显著升高(P＜0.01).结论 垂体后叶素可改善CPB停机后严重低血压患者血流动力学,对肺动脉压无明显影响.     

Comparative hemodynamic effects of vasopressin and norepinephrine after milrinone-induced hypotension in off-pump coronary artery bypass surgical patients

Objective: Phosphodiesterase inhibitor is essential to the pharmacologic management of decompensated heart failure because it increases contractility and decreases afterload of right ventricle. It also improves hemodynamics and increases blood flow of the grafted internal mammary arteries and middle cerebral arteries during coronary artery bypass surgery. However, it induces vasodilation and necessitates the use of vasoconstrictors, such as norepinephrine. We hypothesized that vasopressin could recover hypotension induced by milrinone with less effect on pulmonary vascular resistance (PVR) compared to norepinephrine. Methods: Fifty patients, undergoing coronary artery bypass graft (CABG) surgery, were assigned randomly in a double-blind manner to receive either vasopressin or norepinephrine. After baseline hemodynamic measurements, a loading dose of milrinone 50 μg/kg was infused slowly for 20 min followed by continuous infusion of 0.5 μg/(kg min). Immediately after the loading dose of milrinone, hemodynamic variables were measured, and vasopressin (VP group) or norepinephrine (NE groups) was infused. After being titrated until the mean arterial pressure was increased by 20%, hemodynamic variables were measured again. Results: Milrinone infusion reduced both systemic vascular resistance (SVR, 1218 ± 299 dyne s/cm⁵ vs 838 ± 209 dyne s/cm⁵, 1345 ± 299 dyne s/cm⁵ vs 1011 ± 195 dyne s/cm⁵) and PVR (95 ± 34 dyne s/cm⁵ vs 72 ± 30 dyne s/cm⁵, 119 ± 85 dyne s/cm⁵ vs 87 ± 33 dyne s/cm⁵) in the VP and NE groups, respectively. Vasopressin and norepinephrine infusion increased both SVR (838 ± 209 dyne s/cm⁵ vs 1100 ± 244 dyne s/cm⁵, 1011 ± 195 dyne s/cm⁵ vs 1446 ± 681 dyne s/cm⁵, respectively) and PVR (72 ± 30 dyne s/cm⁵ vs 84 ± 18 dyne s/cm⁵, 87 ± 33 dyne s/cm⁵ vs 139 ± 97 dyne s/cm⁵, respectively). The PRV/SVR ratio was decreased after vasopressin infusion (0.10 ± 0.03 vs 0.08 ± 0.03), while no changes were found after norepinephrine infusion (0.09 ± 0.02 vs 0.09 ± 0.02). Conclusions: In the patients undergoing CABG surgery, both norepinephrine and low dose vasopressin were effective in restoring milrinone-induced decrease of SVR. However, only low-dose vasopressin decreased the PVR/SVR ratio that was increased by milrinone. Considering the importance of maintaining systemic perfusion pressure as well as reducing right heart afterload, milrinone–vasopressin may provide better hemodynamics than milrinone–norephinephrine during the management of right heart failure.     

多巴胺及去甲肾上腺素对感染性休克患者血流动力学和组织氧代谢的影响

目的探讨多巴胺(DA)及去甲肾上腺素(NE)在治疗感染性休克过程中对血流动力学和组织氧代谢的影响。方法选择我科腹部外科术后感染性休克患者46例,按随机原则分别给予DA(DA组)或NE(NE组)升压治疗。分别观察入组时、入组后1~6h的血流动力学指标[心率(HR)、平均动脉压(MAP)、心排出量指数(CI)、每搏指数(SI)、体循环阻力指数(SVRI)]、混合静脉血氧饱和度(SvO2)、早期乳酸清除率、28d死亡率;每小时尿量(UV)和12h后肌酐清除率(Ccr)。结果①两组各时间点MAP、CI、SVRI比较差异均无统计学意义,DA组的HR明显高于NE组,而SI低于NE组(P0.05)。②3h后NE组SvO2值较DA组明显增高(P0.05),6h后NE组SvO2≥65%的比例也明显高于DA组;NE组早期乳酸清除率明显高于较DA组[(24.8±15.7)%vs(16.2±14.2)%,P=0.003],NE组高的早期乳酸清除率比例明显高于较DA组,③两组6h后UV以及12h末的Ccr水平无明显差异。④两组之间28d死亡率无统计学差异。结论NE在内脏灌注和组织氧代谢方面优于DA。对于腹部外科术后感染性休克患者,NE可能是更好的选择。     

Hemodynamic effects of anesthesia in patients chronically treated with angiotensin-converting enzyme inhibitors.

Angiotensin-converting enzyme inhibitors (ACEIs) are increasingly used in the treatment of cardiovascular disease, but recent reports have warned of some hemodynamic risk (hypotension and bradycardia) when associated with anesthesia. To assess the hemodynamic effects of induction of anesthesia in patients chronically treated with ACEIs, 16 hypertensive patients scheduled for coronary artery bypass graft surgery (n = 12) or vascular surgery (n = 4) were studied. Eight of them were chronically treated (for at least 1 mo) with ACEIs (ACEI group), and the remaining eight (control group) were treated with other classes of antihypertensive drugs. Induction of anesthesia, which consisted of flunitrazepam (0.03 mg/kg), fentanyl (0.006 mg/kg), and pancuronium (0.1 mg/kg) IV, was followed by a significant decrease in mean arterial blood pressure from baseline in both groups (by 16.8% in controls [P = 0.001] and 33.5% in ACEI-treated patients [P = 0.001] [P = 0.041 between groups]). In control patients, mean arterial blood pressure decrease was only associated with a significant decrease in cardiac index (-18%, P = 0.014). In ACEI-treated patients, the arterial blood pressure decreases were associated with consistent reductions in pulmonary capillary wedge pressure (-26.4%; P = 0.035) and cardiac index (-23.9%; P = 0.001). Systemic vascular resistance index and heart rate were moderately changed (-14.2% and -4.5%, respectively). Rapid restoration of arterial blood pressure was obtained in all ACEI-treated patients, mainly with the intravenous administration of 0.4 to 0.7 L of lactated Ringer's solution. Phenylephrine (0.38 +/- 0.9 mg) was, however, required in four patients when mean arterial blood pressure was less than 60 mm Hg.(ABSTRACT TRUNCATED AT 250 WORDS)