Diagnosis and treatment of neonatal hypotension outside the transitional period

The etiology and pathophysiology of the circulatory compromise are among the primary determinants of the clinical presentation of patients with neonatal shock. Therefore, in the absence of direct assessment of cardiac output and organ blood flow, the characteristic clinical presentation itself may guide the initial management of the circulatory compromise. This chapter discusses different pathophysiology-driven management approaches to a number of characteristic clinical presentations of neonatal shock. The clinical presentations discussed in detail are the hypotensive very low birth weight neonate with a hemodynamically significant patent ductus arteriosus, and the preterm or term neonate with perinatal depression, pressor/inotrope resistance and relative adrenal insufficiency, and with specific systemic inflammatory response syndrome. In the absence of information from appropriately designed, randomized clinical trials, management of neonatal shock remains based on pathophysiology and experience. Thus, as there is little evidence for the effectiveness of these management approaches to improve mortality and short-and long-term outcome, the therapeutic approaches described in this chapter should be carefully evaluated and cautiously entertained when treating a neonate with circulatory compromise.

Diagnosis and treatment of preterm transitional circulatory compromise

AIM

To determine the evidence for detection and treatment of low systemic and organ blood flow in preterm infants in the first day after birth.

REVIEW

Preterm infants are at risk of low systemic blood flow (SBF) in the first day, with almost all infants who develop low flows doing so by 12 h of age. Risk factors for low SBF include low gestational age, ventilation with higher mean airway pressures, large diameter ductus arteriosus, higher calculated systemic vascular resistance and poor myocardial contractility. Blood pressure and clinical signs such as capillary refill times do not accurately detect infants with low SBF, and result in delayed treatment when treatment is targeted at hypotension. Echocardiography in the first hours (including ventricular outputs and superior vena caval flow) is required to detect infants with low flows. Although dobutamine is better at increasing SBF and dopamine better at increasing blood pressure, neither has been shown to improve mortality or longer-term outcomes. Nearly 40% of infants with low SBF fail to respond to inotropes. Volume expansion should not be used routinely in preterm infants. In infants with refractory hypotension, adrenaline and corticosteroids should be considered. Further trials of echocardiographically directed cardiovascular treatments are required.

Prevention of early sudden circulatory collapse after the Norwood operation

BACKGROUND

After modifications in our perioperative management protocol, we have observed a decrease in sudden circulatory collapse after the Norwood operation. The current study examines early outcomes after the Norwood operation in our unit in an attempt to identify variables that may have altered the risk of unexpected circulatory collapse.

METHODS AND RESULTS

We studied 105 consecutive neonates who underwent a Norwood operation in our institution. Our treatment protocol has changed in the past 3 years to include the use of alpha-blockade with phenoxybenzamine (POB) for systemic afterload reduction and selective cerebral perfusion. Forty-eight infants had selective cerebral perfusion. Forty-two infants received POB. Sixty patients had hypoplastic left heart syndrome. There was no difference in age, diagnosis, number of neonates with weight <2.5 kg, aortic size diameter <2 mm, highest preoperative lactate level, and shunt size indexed to body weight among patients with or without use of POB. Twenty-five infants had circulatory collapse during the first 72 hours. Twelve of them could be explained by technical issues. Thirteen others who appeared clinically stable had early sudden circulatory collapse without an apparent cause. Sixteen out of 25 neonates died. Of those with technical problems, 8 out of 12 died. Based on the hazard function, 3 incremental risk factors for early circulatory collapse were technical issue at operation (P<0.001), longer cross-clamp time (P<0.007), and no use of POB (P<0.002). For a technically successful operation, freedom from circulatory collapse at 72 hours is 95% with the use of POB versus 69% without (P<0.002). Diagnosis, aortic size, atrioventricular valve function, birth weight, age at operation, and total circulatory arrest time and were not predictive of early sudden circulatory collapse.

CONCLUSIONS

Recent changes in our treatment protocol have resulted in a decrease incidence of sudden circulatory collapse after the Norwood operation. Optimal surgical technique is the most important predictor of early survival. The use of aggressive afterload reduction with POB reduced the risk of early sudden arrest.

Risk stratification after hospitalization for decompensated heart failure

BACKGROUND

Decompensated heart failure (HF) is among the most common indications for hospitalization in the United States, but little is known about features on admission that predict adverse events. We used data from the Outcomes of a Prospective Trial of Intravenous Milrinone for Exacerbations of Chronic Heart Failure (OPTIME-CHF) study to develop a model that would predict outcomes in patients with decompensated HF.

METHODS AND RESULTS

OPTIME-CHF randomized 949 patients hospitalized with decompensated HF for 48 to 72 hours of infusion of either milrinone or placebo. We used multivariable modeling to evaluate variables on admission that would be predictive of 60-day mortality or the composite of death or rehospitalization at 60 days. Variables at presentation that predicted death at 60 days were increased age, lower systolic blood pressure, New York Heart Association class IV symptoms, elevated blood urea nitrogen (BUN), and decreased sodium. Predictors of the composite of death or rehospitalization within 60 days were the number of HF hospitalizations in the preceding 12 months, elevated BUN, lower systolic blood pressure, decreased hemoglobin, and a history of percutaneous coronary intervention (PCI). The discriminatory power of the model was substantial for the mortality model (c-index .77) but less for the composite endpoint (c-index .69).

CONCLUSIONS

Risk stratification of patients with decompensated HF may be accomplished using easily assessed clinical variables. Further research into the validity of this model in independent samples will potentially aid in the development of risk stratification strategies.

Therapeutic efficacy of milrinone in the management of enterovirus 71-induced pulmonary edema

Hand, foot, and mouth disease and herpangina are the major clinical manifestations of enterovirus 71 (EV71) infections. Brain-stem encephalitis and pulmonary edema are severe complications that can lead to death. This study was designed to evaluate the potential therapeutic effect of milrinone, a phosphodiesterase (PDE) inhibitor, in the treatment of patients with EV71-induced pulmonary edema. We conducted a historically controlled trial of 24 children with severe EV71-induced pulmonary edema from April 1998-June 2003 in southern Taiwan. Patients were divided into groups treated before and after the introduction of milrinone therapy. Etiological diagnosis was established by viral cultures and confirmed by specific immunofluorescence and neutralization tests. All 24 patients were below 5 years of age. The mortality was lower in the milrinone-treated vs. nontreated group (36.4% vs. 92.3%, P=0.005). Sympathetic tachycardia was decreased in patients treated with milrinone compared to controls (144 +/- 17/min vs. 206 +/- 26/min, P=0.004). A marked decrease in IL-13 (77 +/- 9 pg/ml vs. 162 +/- 88 pg/ml, P=0.001) was observed in milrinone-treated patients compared to controls. There was a significant reduction in white blood cell (10,838 +/- 4,537/mm3 vs. 19,475 +/- 7,798/mm3, P=0.009) and platelet (257 +/- 45 x 10(3)/mm3 vs. 400 +/- 87 x 10(3)/mm3, P=0.001) counts in milrinone-treated patients compared to controls. These results were associated with improvement in sympathetic regulation and decrease in IL-13 production. Milrinone therapy may provide a useful therapeutic approach for this highly lethal disorder.

Reduction of diabetes-induced oxidative stress by phosphodiesterase inhibitors in rats

Increased oxidative stress has been suggested to be involved in the pathogenesis and progression of diabetic tissue damage. The aim of this study was to investigate the effect of different phosphodiesterase inhibitors on lipid peroxidation and total antioxidant capacity (TAC) of plasma in streptozotocin-induced diabetic rats (Rattus norvegicus). Rats became diabetic by a single administration of streptozotocin (STZ, 45 mg/kg). The effects of 15-days treatment by milrinone, sildenafil, and theophylline as cyclic-AMP and -GMP phosphodiesterase inhibitors (PDEIs) on diabetes-induced oxidative stress were studied. The levels of glucose, malonedialdehyde (MDA) the by product of lipid peroxides, and TAC (FRAP test) were estimated in plasma of control and experimental groups of rats. A significant increase in the levels of plasma glucose, and MDA and a concomitant decrease in the levels of TAC were observed in diabetic rats. These alterations were reverted back to near normal level after the treatment with PDEIs. Treatment of diabetic rats by PDEIs reduced MDA levels and increased TAC in the order of milrinone>sildenafil>theophylline. In conclusion, the present investigation show that PDIS possesses antioxidant activities, which may be attributed to their enhancing effect on cellular cyclic nucleotides contributing to the protection against oxidative stress in streptozotocin-induced diabetes. Exact mechanism of protective actions of cAMP- and cGMP-phosphodiesterase remains to be elucidated by further studies. This finding may suggest a place for PDEIs in maintaining health in diabetes.

A prospective study of continuous intravenous milrinone therapy for status IB patients awaiting heart transplant at home

BACKGROUND

We performed a prospective study to determine the feasibility and safety of continuous intravenous milrinone therapy administered at home in patients listed as Status IB for heart transplant.

METHODS

Patients who were Status IB could participate if they met specific criteria including an optimal dose of milrinone < or =0.5 microg/kg/min, presence of an implantable cardioverter-defibrillator (ICD), and no other serious comorbidity. The primary end-point of the study was survival to transplant. Hospitalizations, quality of life and cost comparisons were assessed.

RESULTS

From May 1999 through October 2002, a total of 60 patients (51 men, 9 women), aged 55.5 +/- 8.4 years, entered the study. Before milrinone therapy, cardiac index was 1.98 +/- 0.66 liters/min/m2 and peak oxygen consumption was 11.4 +/- 2.6 ml/kg/min. Mean time in the study was 160.1 +/- 151.8 days. Fifty-three patients (88.3%) underwent heart transplant. There were only 2 deaths during the study. There were 89 hospital admissions in 46 patients over the 43-month follow-up period; 58 of these admissions were for heart failure. There were 6 episodes of ICD firing for ventricular tachycardia. Quality-of-life measures in a sub-group of patients significantly improved 1 month after discharge. Substantial estimated cost savings occurred.

CONCLUSIONS

Continuous intravenous milrinone therapy can be safely administered at home in selected patients with advanced heart failure who are listed for transplant. This strategy may be an acceptable alternative to prolonged hospitalization for patients dependent on continuous inotropic support. Re-hospitalization is to be expected. An implantable cardioverter-defibrillator should be present due to the incidence of ventricular tachycardia.

Left ventricular conditioning in the elderly patient to prevent congestive heart failure after transcatheter closure of atrial septal defect

Transcatheter closure of atrial septal defects (ASDs) is a safe and effective treatment. Over the past years, an increasing number of elderly patients (age > 60 years) have been admitted for transcatheter closure to prevent ongoing congestive heart failure from volume overload. However, recent data point to the risk of serious acute left ventricular dysfunction leading to pulmonary edema immediately after surgical or transcatheter ASD closure in some patients. In this study, we used a technique described before to recognize in advance patients at risk of left heart failure after ASD closure. Those patients at risk were then treated with preventive conditioning medication for 48-72 hr before definitive transcatheter ASD closure was performed. Fifty-nine patients aged over 60 years (range, 60-81.8 years; median, 68 years) were admitted to our institution for transcatheter closure of an atrial septal defect. All patients received evaluation of atrial pressures before and during temporary balloon occlusion of the ASD. Patients with left ventricular restriction due to increased mean atrial pressures (> 10 mm Hg) during ASD occlusion received anticongestive conditioning medication with i.v. dopamine, milrinone, and furosemide for 48-72 hr before definitive ASD closure with an Amplatzer septal occluder was performed. In 44 patients without any signs of left ventricular restriction, ASD closure was performed within the first session. Fifteen (25%) out of 59 patients showed left ventricular restriction. In the majority of patients with LV restriction, the mean left atrial pressures with occluded ASD were significantly decreased after 48-72 hr of conditioning medication. Definitive ASD closure was then performed in a second session. Only two patients received a fenestrated 32 mm Amplatzer occluder due to persistent increased atrial pressures > 10 mm Hg even after conditioning medication. There were no significant differences in shunt, device size, or defect size between the two groups. Balloon occlusion of atrial septal defects identifies patients with left ventricular restrictive physiology before ASD closure. Intravenous anticongestive conditioning medication seems to be highly effective in preventing congestive heart failure after interventional closure of an ASD in the elderly patient with a restrictive left ventricle.

Oral Sildenafil Reduces Pulmonary Hypertension After Cardiac Surgery

BACKGROUND

Treatment of postoperative pulmonary hypertension with intravenous (IV) pulmonary vasodilators is hampered by the lack of selectivity. Inhaled nitric oxide produces selective pulmonary vasodilation; however, it requires a special device, and weaning can cause rebound. Oral sildenafil is a phosphodiesterase type V inhibitor. Sildenafil can produce sustained pulmonary vasodilatation in patients with hypoxic or primary pulmonary hypertension; however, experience with postoperative pulmonary hypertension is limited. We report our initial experience with eight patients who received oral sildenafil as adjunctive therapy for postoperative pulmonary hypertension

METHODS

We reviewed the charts of eight adult patients with postoperative pulmonary hypertension who received oral sildenafil (25 to 50 mg) to facilitate weaning of IV (milrinone, nitroglycerine, and sodium nitroprusside) and inhaled (nitric oxide) pulmonary vasodilators. Hemodynamic data were recorded before and 30 and 60 minutes after the initial dose of sildenafil.

RESULTS

After the initial dose of sildenafil, mean pulmonary artery pressure was reduced by 20% and 22% at 30 and 60 minutes, respectively (p < 0.05). Pulmonary vascular resistance index decreased by 49% and 44% at 30 and 60 minutes, respectively (p < 0.05). Sildenafil had no clinically significant effects on cardiac index, mean arterial pressure, or systemic vascular resistance. Subsequent doses of sildenafil were administered at regular intervals, allowing successful weaning of concomitant pulmonary vasodilators.

CONCLUSIONS

Oral sildenafil is an effective agent for treatment of postoperative pulmonary hypertension and can be used to facilitate weaning of inhaled and IV pulmonary vasodilators.

Application of Papillary Muscle Sling Concept in an Infant as a Biological Bridge to Transplantation

We successfully applied the papillary muscle sling concept in mitral valve reconstruction of an infant with dilated cardiomyopathy. This new method of banding the two papillary muscles together can shorten the distance of the base between the two papillary muscles, reduce the severity of mitral regurgitation, and remodel the dilated left ventricle without any mitral stenosis. The infant survived after this bridge-to-transplantation procedure and was successfully transplanted.

Intravenous milrinone infusion improves congestive heart failure caused by diastolic dysfunction: a brief case series

Although there have been significant advances in the medical treatment of heart failure patients with impaired systolic function, very little is known about the diagnosis and treatment of diastolic dysfunction. We report the cases of 3 patients in New York Heart Association functional class IV who had echocardiographically documented diastolic dysfunction as the main cause of heart failure. All 3 patients received medical therapy with long-term milrinone infusion.

Effect of aerosolized milrinone during drug-induced pulmonary hypertension in lambs

We tested whether aerosolized milrinone in lambs selectively reduces drug-induced acute pulmonary hypertension without reducing the mean systemic blood pressure (MSBP). Seven, 2-3-week-old lambs were anesthetized (50 mg/kg ketamine), paralyzed (0.1 mg/kg vecuronium bromide) and mechanically ventilated. A femoral artery, pulmonary artery, and jugular vein were catheterized for continuous monitoring of MSBP, mean pulmonary artery pressure, periodic gas-exchange analyses, and determination of cardiac output by thermodilution technique. An Airlife Misty nebulizer was used in a dry state to establish a stable baseline of an inspired fraction of oxygen (FiO(2)) at 0.21. Acute pulmonary hypertension with hypoxemia was then induced by increasing the mean pulmonary artery pressure up to 30-35% of the MSBP using 2-6 microg/kg/min of Thromboxane A(2) mimetic (U-46619), intravenously. The lambs were then subjected to 15 min of saline nebulization without milrinone followed by 30 min saline nebulization with a relatively high concentration of milrinone (10 mg/ml, total dose of 40 mg). Aerosolized milrinone had no effect on systemic or pulmonary artery pressure during combined acute pulmonary hypertension and hypoxemia. We speculate that our nebulization procedures failed to deliver sufficient amount of milrinone for producing a detectable hemodynamic effect.

Efficacy of pre-emptive milrinone in off-pump coronary artery bypass surgery: comparison between patients with a low and normal pre-graft cardiac index

OBJECTIVE

The effect of pre-emptive milrinone without bolus during off-pump coronary artery bypass surgery (OPCAB) was evaluated in two groups of patients with low and normal pre-graft cardiac index.

METHODS

Eighty-two patients were divided into two groups based on their pre-graft cardiac index. Each group was randomly subdivided into two groups to receive either milrinone or normal saline. After the internal mammary artery was harvested, the infusion of milrinone, or normal saline was started and maintained until the end of the anastomosis. The haemodynamic variables were measured: just before the start of milrinone or normal saline after pericardiotomy (baseline value); 10 min after the tissue stabilizer had been applied for the anastomosis of left anterior descending artery, left circumflex artery and right coronary artery; and after the sternal closure.

RESULTS

Milrinone reduced the extent of the decrease in cardiac index and stroke volume as well as the extent of the increase in systemic and pulmonary vascular resistance. The extent of the decrease in cardiac index and mixed venous oxygen saturation were greater in normal pre-graft cardiac index group than in low pre-graft cardiac index group regardless of milrinone infusion during anastomoses. The effect of milrinone on haemodynamics showed no significant difference between low and normal pre-graft cardiac index groups.

CONCLUSIONS

Pre-emptive milrinone infusion without bolus effectively improved cardiac performance during OPCAB and was especially useful for patients with low pre-graft cardiac index to prevent the decrease in cardiac index and stroke volume index below the critical level.

Off-pump epicardial tissue sealing—a novel method for atrioventricular disruption complicating mitral valve procedures

BACKGROUND

Atrioventricular disruption (AVD) is a rare (1%-2%) but fatal complication after mitral valve procedures; the intraoperative mortality is more than 50% despite the current standard procedure of surgical closure of the defect. We compared the outcome of 9 patients with intraoperative AV disruption, 4 being surgically treated on-pump and 5 receiving epicardial tissue sealing off-pump.

METHODS

Between March 1998 and May 2002 a total of 9 patients presented with AV disruption intraoperative. The first 4 patients were treated with surgical repair on-pump by reconstruction of the defects with patch or buttressed suture. The second series of 5 patients were treated with a biodegradable collagen system with fibrinogen-based coating off-pump. Three to six layers were placed over the bleeding site with manual pressure for 30-60 minutes on the beating heart until bleeding was stopped. Cell saved blood was retransfused.

RESULTS

In the on-pump surgical repair group 3 patients (75%) died within the first day after repair either because of persistent bleeding or cardiac tamponade. One patient survived at 30 days and 1 year. In the off-pump tissue sealing group 30 days and 1 year survival was 100%. Postoperative echocardiography showed normal left ventricular (LV) function with no regional wall motion abnormalities.

CONCLUSIONS

Our data show that epicardial tissue sealing off-pump results in successful termination of bleeding from AVD and considerably improves survival when compared with the standard procedure. Because of this tremendous improvement in patient survival we now consider this technique as standard therapy for AV disruption in our center.

New positive inotropic agents in the treatment of left ventricular dysfunction

Three major classes of inotropic agents have been clinically evaluated in patients with left ventricular dysfunction: a) agents that increase the intracellular concentration of cyclic adenosine monophosphate by stimulating the beta-adrenergic receptor or inhibiting phosphodiesterase; b) drugs that increase the intracellular sodium concentration; c) the new calcium-sensitizing drugs. This review will focus on the newest drug for each of the above-mentioned classes of inotropic agents. Moreover, we present a new protocol which provides the use of levosimendan in patients with post-ischemic left ventricular dysfunction.

[Differences in outcome in patients with poor grade subarachnoid hemorrhage (WFNS grade IV and V): according to the perioperative management against vasospasm]

Cerebral vasospasm remains a leading cause of morbidity and increasing mortality rates following aneurysmal subarachnoid hemorrhage (SAH). The rate of vasospasm and the outcome (Glasgow Outcome Scale; GOS) especially in poor WFNS grade were retrospectively analyzed over a 6-year period. Patients were divided into three different groups. The first group (pre-group) consisted of 43 patients (grade IV: 31, grade V: 12), who were admitted between 1996 and 1998. When vasospasm occurred, they were mainly treated by papaverine (PPV) and percutaneous transluminal angioplasty (PTA). In the second group (mil-cis group), for the prevention of vasospasm, cisternal irrigation therapy with milrinone was applied in 24 patients (grade IV: 13, grade V: 11), who were admitted in the period between 1999 and 2001. The third group, (w/o mil-cis group), consisted of 30 patients (grade IV: 15, grade V: 15), in whom cisternal irrigation therapy was not able to be carried out. In grade IV, vasospasm was observed in 66% of the patients the first group, 50% in the w/o mil-cis group and significantly less in the mil-cis group (15%, p<0.024). In grade V, the rate of vasospasm was also lower in the mil-cis group but no statistical significance was revealed. Although the rate of favorable outcome in GOS was highest and the rate of death was least in the mil-cis group in both grade IV and V, only the trend was observed. Many factors should be considered, Cisternal irrigation therapy with milrinone reduced the occurrence of vasospasm. However, outcome was not improved because of the initial poor clinical condition.

Dobutamine-related asthma in a patient awaiting cardiac transplantation: the eosinophilic dilemma

Long-term continuous intravenous inotrope infusion is frequently used as a pharmacologic bridge to cardiac transplantation in patients with end-stage congestive heart failure. We report a case of severe eosinophil-associated asthma after 6 weeks of therapy with the inotrope dobutamine in a patient awaiting cardiac transplantation. Review of the laboratory data revealed a steady increase in eosinophils during the period of treatment with dobutamine. Once the patient was switched to an alternative inotrope, milrinone, the eosinophil count returned to normal, and the asthma exacerbation resolved.

A rational approach for the treatment of acute heart failure: current strategies and future options

PURPOSE OF REVIEW

Acute decompensated heart failure represents a major, growing health problem in the developed world. However, until recently, relatively little research has been performed in this field to provide a basis for rational treatment strategies. The purpose of this review is to discuss the current approach and the potential future strategies for treatment of patients with acute decompensated heart failure.

RECENT FINDINGS

Recent data have confirmed the heterogeneous nature of patients admitted with acute decompensated heart failure, and the limitations of the current therapeutic regimens with diuretics, intravenous vasodilators (ie, nitroglycerin, nitroprusside), and intravenous inotropes (ie, dobutamine, milrinone). A new vasodilator, nesiritide, has been demonstrated to improve hemodynamics and symptoms at 3 hours compared with nitroglycerin, and has been added to the therapeutic armamentarium in the United States. However, none of these agents has been shown to influence patient outcomes favorably. Given the high readmission rates, morbidity, and mortality of acute decompensated heart failure, other newer approaches, such as antagonists to a number of neurohumoral targets (ie, endothelin [tezosentan], vasopressin [conivaptan, tolvaptan], and adenosine) and non-cAMP-mediated inotropy (ie, levosimendan), are currently under investigation and showing promise.

SUMMARY

Acute decompensated heart failure presents a challenging therapeutic problem for clinicians. Although they readily correct the hemodynamic abnormalities, current treatment strategies have significant limitations and have not been shown to improve morbidity or mortality. A number of new agents are under investigation with the goal of improving patient outcomes.

Milrinone and nitric oxide: combined effect on pulmonary artery pressures after cardiopulmonary bypass in children

OBJECTIVE

To investigate the effect of milrinone combined with nitric oxide (NO) on the pulmonary artery pressures (PAP) after cardiopulmonary bypass (CPB), for repair of congenital heart defects (CHD) in children.

DESIGN

Prospective, randomized, double-blind study.

SETTING

University affiliated community hospital.

PARTICIPANTS

Ninety children with pulmonary hypertension and repair of CHD.

INTERVENTIONS

After weaning from CPB, patients (30 in each group) received 3 drug regimens: group 1, nitric oxide (NO); group 2, a continuous infusion of milrinone; and group 3, a combination of the 2. Drugs were started after CPB and given for 20 minutes.

MEASUREMENTS AND MAIN RESULTS

Pulmonary and systemic pressures, PaCO(2), SaO(2), and pH values were recorded before bypass, after weaning from CPB, 10 and 20 minutes after starting each regimen, and 10 minutes after the cessation of treatment. Mean systemic blood pressure was lower (p < 0.05) in the combined treatment group after discontinuation of the drugs. Although mean PAP values were lower in the combined group (p < 0.05), no difference was recorded with regard to pH, PaCO(2), and PaO(2). The ratio between pre- and post-treatment mean PAP was highest in group 3(1.26 +/- 0.5) and lowest in group 2 (0.99 +/- 0.3, p < 0.001). The mean PAP recorded after discontinuation of the drug was lower than the baseline value in groups 1 and 3 (p < 0.05).

CONCLUSIONS

The combination of milrinone and NO produced a more pronounced decrease in PAP than milrinone alone.

Milrinone Reduces Cerebral Vasospasm After Subarachnoid Hemorrhage of WFNS Grade IV or V

The preventative effect of cisternal irrigation with milrinone against vasospasm was evaluated in 12 patients with subarachnoid hemorrhage (SAH) of World Federation of Neurosurgical Societies grade IV or V treated between September 1999 and September 2000. All aneurysms were clipped or embolized within 72 hours of the onset of SAH. Inlet and outlet tubes were placed in either the supratentorial cisternal space, lateral ventricle, or spinal subarachnoid space. Lactated Ringer solution containing urokinase (120 IU/ml), ascorbic acid (3.5 mg/ml), and milrinone (3.6 microg/ml) was continuously infused at 30 ml/hr for as long as 2 weeks. Angiographical vasospasm was detected in only two of the 11 patients who received milrinone irrigation and underwent postoperative angiography. Vasospasm may have resulted from irrigation obstruction associated with pneumocephalus in one patient and clot in the sylvian fissure in the other patient. The outcome of the milrinone irrigation therapy was significantly better than that of the conventional therapy. This study suggests that cisternal irrigation with milrinone is safe and effective, and reduces the occurrence of vasospasm in patients with poor grade aneurysmal SAH.

Tratamiento inotrópico en la insuficiencia cardíaca: aspectos generales y resultados clínicos

Classic inotropic agents such as beta-adrenergic agonists and phosphodiesterase III inhibitors have beneficial but transitory hemodynamic effects in patients with acute and chronic heart failure. In this context, the available data suggest that long term inotropic therapy has a negative impact on morbidity and mortality in patients with heart failure. For this reason, these agents are mainly used for the treatment of refractory episodes of decompensation and they are also used as a "bridge" (transplant, revascularization, recovery) or as a palliative measure. We present a revision of the general aspects of inotropes including main published clinical trials and some findings of its combined use with beta blockers. Furthermore, we describe a promising and differential therapeutic approach represented by calcium sensitizer agents (levosimendan).