National survey of diagnosis and management of persistent pulmonary hypertension of the newborn.

The diagnosis and management of persistent pulmonary hypertension of the newborn remains controversial. A national survey was performed to analyze recent trends in the incidence, diagnosis, management, and survival of patients with persistent pulmonary hypertension of the neonate. Sixty-six institutions from all geographical regions responded. The overall admission incidence was 3.9% +/- 2.6%. Secondary persistent pulmonary hypertension of the neonate was more common than primary. Unexplained hypoxemia, ductal level right-to-left shunting, echocardiography, and a positive response to hyperventilation were all used frequently (in at least 79% of institutions) to diagnose persistent pulmonary hypertension of the neonate. The majority of institutions considered a positive response to hyperventilation to be determined by an increase of PaO2 by 30 mm Hg with a concomitant decrease in PaCO2 to 25 mm Hg. Approximately 70% of institutions use varying ventilator techniques (ie, with or without hyperventilation), but the majority use hyperventilation predominantly. Almost all (greater than 90%) institutions used muscle paralytic agents and pulmonary vasodilators. Tolazoline was the first choice of pulmonary vasodilator therapy. The overall survival rate of persistent pulmonary hypertension of the newborn was 77.4% +/- 13.4%. Survival rate did not differ between different geographic areas of the country. There was a trend noted for improved survival with less use of muscle paralyzing agents. Yet despite varying treatment protocols, survival rates are improving.

[Cardiac arrhythmia and myocardial contraction in opium and ephedrone addiction]. / Narusheniia ritma serdtsa i sokratimost' miokarda pri opiinoi i éfedronovoi narkomanii.

Sixty-two patients with opium and ephedrone abuse were studied. They underwent 24-hour Holter monitoring, resting ECG and echocardiography, 18 of them having volumetric loading with polyglucine, 400.0 ml, i.v. Sinus tachycardia was detected in 67.4%, ventricular extrasystole in 4.7%, supraventricular extrasystole with infrequent paroxysms of supraventricular tachycardia in 11.6%. Despite the fact that signs of heart failure were absent and myocardial contractility was normal at rest, echocardiography along with volume loading allow one to reveal in patients some abnormal contractile alterations in the left ventricle. These include its increased volumes, decreased ejection fraction and circulatory shortening rate of myocardial fibers, which suggests that the compensatory potentials of the myocardium are reduced in drug abuse.

Echocardiography in hypertension. Dimensions and mass of the left ventricle. Comparison with controls and sportsmen.

The investigation was carried out to determine dimensions and mass of the left ventricle (LV) in relation to the stages of essential arterial hypertension (HT). 93 male non-congestive hypertensives (WHO stages I to III) were examined by means of echocardiography (UCG) (2.25 MHz single element transducer), using the T - M - technique (Organon - Technika, The Netherlands). The results were compared with those of 75 controls and 21 endurance sportsmen. Differences in the wall thickness of the LV in the hypertensives compared with that in normotensive subjects can be shown quite easily. For this purpose the UCG is more sensitive than an ECG. There is, however, a poor correlation between the WHO stages and the actual wall thickness. On the other hand, a close correlation was found to exist between wall thickness and average systolic, diastolic and mean blood pressure (r = 0.72, 0.68, 0.70). The LV dimensions do not differ substantially from those obtained for normotensives. The ventricular mass/volume ratio shows a characteristic shift towards the mass in HT. This quotient helps to differentiate between various forms of hypertrophy and/or dilatation as demonstrated for instance in sportsmen.

Changes in left ventricular diameter during intravenous induction of anesthesia.

Transthoracic two-dimensional echocardiography was used to measure left ventricular diameter in end-systole and end-diastole during anesthetic induction in 11 patients before coronary artery bypass grafting. Midazolam, 0.1 mg/kg, and fentanyl, 6 to 10 micrograms/kg, were used followed by pancuronium, 0.1 mg/kg. Lidocaine, 1.5 mg/kg, was given topically in the airways before intubation. During induction of anesthesia there was a gradual decrease in diastolic diameter (preload) and in systolic diameter and pressure (afterload). The decrease in end-diastolic diameter from 4.6 cm to 3.9 cm indicated a decrease in preload, defined as end-diastolic volume, by approximately 34%. These results are in agreement with earlier findings using calculated ventricular volumes, based on the determination of either ejection fraction with radionuclide cardiography or stroke volume with thermodilution, during induction of anesthesia with thiopental, diazepam, fentanyl, and pancuronium.

Myocardial performance index with sevoflurane-pancuronium versus fentanyl-midazolam-pancuronium in infants with a functional single ventricle.

BACKGROUND: Patients with congenital heart disease characterized by a functional single ventricle make up an increasing number of patients presenting for cardiac or noncardiac surgery. Conventional echocardiographic methods to measure left ventricular function, i.e., ejection fraction, are invalid in these patients because of altered ventricular geometry. Two recently described Doppler echocardiographic modalities, the myocardial performance index and Doppler tissue imaging, can be applied to single-ventricle patients because they are independent of ventricular geometry. This study assessed the changes in myocardial performance index and Doppler tissue imaging in response to two anesthetic regimens, fentanyl-midazolam-pancuronium and sevoflurane-pancuronium. METHODS: Thirty patients aged 4-12 months with a functional single ventricle were randomized to receive fentanyl-midazolam or sevoflurane. Myocardial performance index and Doppler tissue imaging were measured by transthoracic echocardiography at baseline and two clinically relevant dose levels. RESULTS: Sixteen patients receiving sevoflurane and 14 receiving fentanyl-midazolam were studied. Myocardial performance index was unchanged from baseline with either agent (fentanyl-midazolam: 0.50 +/- 15 baseline vs. 0.51 +/- 0.15 at dose 2; sevoflurane: 0.42 +/- 0.14 baseline vs. 0.46 +/- 0.09 at dose 2). Doppler tissue imaging S (systolic)- and E (early diastolic)-wave velocities in the lateral ventricular walls at the level of the atrioventricular valve annulus were unchanged in the sevoflurane group; however, both Doppler tissue imaging S- and E-wave velocities were decreased significantly from baseline at dose 1 and dose 2 with fentanyl-midazolam, consistent with decreased longitudinal systolic and diastolic ventricular function. CONCLUSIONS: Myocardial performance index, a global measurement of combined systolic and diastolic ventricular function, is not affected by commonly used doses of fentanyl-midazolam or sevoflurane in infants with a functional single ventricle.