Psychomotor and intellectual development after deep hypothermia and circulatory arrest in early infancy.

Somatic, psychomotor, and intellectual development were studied in 11 patients who had total correction of congenital cardiac malformation in early infancy by the method of surface-induced deep hypothermia and circulatory arrest up to 43 minutes. Time between operation and re-evaluation ranged from 3 to 11 years (average 7 years). Somatic development was normal in all children. Psychomotor and intellectual behavior, measured by a battery of specially adapted test methods, failed to show a statistically significant difference when compared between the study group, a matched control group, and the normal population. Normal scores in psychomotor tests and normal intelligence quotients (I.Q.) were present in 8 patients; mental retardation was found in 2 patients: and unstable behavior, evident from different tests, was present in one. Except for the last case, in none of the patients was the method was found to be the primary cause of the abnormal behavior. Deep hypothermia and circulatory arrest in early infancy does not appear to have a negative influence on somatic, psychomotor, or intellectual development.

Haemodynamic effects of dopamine, epinephrine and orciprenaline (Alupent) in patients early after cardiac surgery.

The haemodynamic effects of Dopamine (100, 250 and 500 mcg/min), Epinephrine (4 and 8 mcg/min), Orciprenaline (4 and 8 mcg/min) and two combinations of Dopamine 250 mcg/min with Epinephrine and Orciprenaline 4 mcg/min respectively at constant infusion rates were studied in 21 patients after cardiac surgery. Special attention was payed to four types of catecholamine infusions during which the highest cardiac index (CI), 161-168% of control, was seen: Dopamine 500 mcg/min (D 500), Epinephrine 8 mcg/min (E 8), Dopamine 250 mcg/min combined with Epinephrine 4 mcg/min (D 250 + E4) and Dopamine 250 mcg/min combined with Orciprenaline 4 mcg/min (D 250 + Or 4). At the same time mean arterial pressure (MAP) was highest with D 500 (137%) and lowest during both combined infusions (120 and 125%). Total peripheral resistance (TPR) was lowest during the combined infusions (80 and 81% of control) and highest during D 500 (89%). The relative increase of stroke index (SVI) and heart rate (HR) in favor of SVI, given as a quotient SVI/HR, was highest with D 250 + E4(3.7), followed by E 8 (1.9), D 500 (1.6) and D 250 + Or 4 (1.3). It was concluded that a combined infusion of Dopamine and Epinephrine, both in low doses, is preferable to a high dose of Dopamine, or Epinephrine alone, producing the same increase of cardiac output with less afterload and less chronotropic effect than high doses of either drug alone.

Complications during and following radial artery cannulation: a prospective study.

One hundred and eighteen 20-g radial artery catheters were prospectively evaluated in 109 cardiovascular surgical patients. 0.024% papaverine in saline was used as a continuous flushing solution. Using the Doppler method, obstruction of the radial artery with the catheter in situ was found in 11 (9.8%) patients. Decannulation was performed at the end of the monitoring in 93 (78.9%) cases while 25 (21.1%) catheters had to be removed earlier. According to Allen's radial flush and Doppler evaluation after decannulation, three (2.5%) radial artery occlusions and one stenosis persisted. However, no vascular insufficiency occurred during the study period. Female patients developed more complications with the catheter in situ but not after catheter removal. Wrist size did not predict the complications. Age, concomitant diseases, traumatic cannulation, type of the surgery, longer cannulation time and perioperative complications did not influence the incidence of abnormal radial blood flow after decannulation. Our results confirm the low incidence of significant complications following radial artery cannulation.

The effect of dopamine on hepatic-splanchnic blood flow after open heart surgery.

Dopamine (3,4 dihydroxyphenylethylamine) increases cardiac output and in particular the renal blood flow at the expense of other regional vascular beds not yet defined. Since the results of dopamine-induced changes in splanchnic perfusion are inconsistent, the effect of 6 mcg/kg/min dopamine was studied in 9 patients early after open heart surgery. Estimated hepatic blood flow (EHBF) was calculated from the concentration-time slopes of Indocyanine Green (ICG, Cardiogreen) in arterial and hepatic venous blood following single intravenous injection. Blood volume was measured using 51Cr tagged red cells. Cardiac output was determined according to the Fick method. 6 mcg/kg/min dopamine caused a mean EHBF-increase of 82%, from 492 +/- 64 to 824 +/- 80 ml/min/m2 (P less than 0.001). Related to the corresponding increase in cardiac index (CI) from 2.6 +/- 0.2 to 3.8 +/- 0.3 1/min/m2 (P less than 0.001), the EHBF/CI-ratio changed from 18.5 to 21.7% (P less than 0.025). The arterial-hepatic venous oxygen difference was reduced from 7.40 +/- 0.53 to 4.91 +/- 0.60 Vol% (P less than 0.001). It was concluded that splanchnic perfusion does not contribute to the preferential increase of renal blood flow under dopamine under the above mentioned conditions. Dopamine had the most beneficial effect on EHBF in two cases where the latter was severely reduced.

[The influence of PaCO2 on oxygen consumption during extracorporeal circulation in hypothermia (author's transl)]. / Der Einfluss der arteriellen Kohlensäurespannung auf den Sauerstoffverbrauch während extrakorporellem Kreislauf in Hypothermie

Hypocapnia during extracorporeal circulation in hypothermia increases oxygen consumption. Po2 in mixed venous blood decreases. This probably reflects a decrease in tissue oxygen tension. Hyperventilation will therefore increase the risk of hypoxia in critically perfused tissues. Therefore we recommend to keep PaCO2 (T) constant at 40 mm Hg during hypothermia.

[Blood sugar levels and acid-base balance in babies before, during and after open-heart surgery with hypothermia and extracorporeal circulation (author's transl)]. / Blutzucker- und Säure-Basen-Veränderungen bei Säuglingen vor, während und nach herzchirurgischen Eingriffen in Hypothermie und extrakorporaler Zirkulation

New borns and babies with congenital heart disease in poor condition have been shown to have a higher risk of developing hypoglycaemia. Blood sugar levels (BSL), acid-base balance and oxygen saturation have been studies in 10 babies from 7.5 to 15 months of age, weighing less than 9kg, before, during and after open-heart surgery. Preoperative mean BSL in the anaesthetized patient was 76mg per cent. It rose slightly after the onset of surgery and further increased to an average of 205mg per cent during cardio-pulmonary bypass with the temperature stablized at 28-29 degrees C. In the early postoperative phase BSL normalized but slowly, reaching a mean value of 107mg per cent 20-24h after the end of surgery. These results demonstrate that, at least under the usual conditions of extracorporeal circulation and hypothermia at our clinic, hypoglycaemia is not a threat in babies undergoing open-heart surgery for total correction of congenital lesions. The possible mechanisms leading to the observed hyperglycaemia are discussed and the results compared with similar studies in adult patients.

[Cardio-pulmonary complications, respiratory treatment and PaO2 after open heart surgery (author's transl)]. / Kardiopulmonale Komplikationen, Beatmungsdauer und arterielle Sauerstoffspannung nach Operationen am offenen Herzen.

Despite the almost complete disappearance of the so called "postperfusion lung syndrome" after cardiac surgery with extracorporeal circulation (ECC), there is still a need for respiratory treatment in some cases, primarily for cardio-circulatory or respiratory reasons. In addition postoperative artificial ventilation is provided routinely in many centers for at least a few hours, until stabilization of cardio-circulatory and metabolic state is achieved. In 4 groups (I-IV) with a total of 659 patients (18 to 72 years old) undergoing open cardiac surgery for acquired heart disease (I: aortic valve, II: mitral valve, III: multivalvular disease, IV: coronary artery disease) postoperative cardio-circulatory and pulmonary complication rate, duration of artificial ventilation needed, PaO2 and some influencing factors have been evaluated. Group II and III show the highest rate of complications, 15.5 and 19.8% respectively, versus 7.7 and 8.1% in group I and IV respectively. The mean duration of postoperative respiratory treatment in cases with complications within all groups (133--156 h) is about 6 times the duration of respiratory treatment in the non complicated cases (23--24 h). In all 4 groups mean PaO2 at the time of extubation is lower for the complicated compared with the non complicated cases. Age of patients, severity of disease, preoperative pulmonary function, prolonged duration of ECC and myocardial ischemia have been found to be predisposing factors for postoperative cardio-pulmonary complications, whereas the duration of anesthesia and the type of anesthesia do not show any influence.

Membrane and bubble oxygenator: a clinical comparison in patients undergoing aortocoronary bypass procedures.

Forty patients undergoing aortocoronary bypass procedures were randomyl allocated to a bubble oxygenator group (20 patients) and a membrane oxygenator group (20 patients). Blood chemistry, hematology and hemodynamics before, during and after cardiopulmonary bypass were used to compare the two oxygenators. There was no mortality and no serious complications in both groups. A higher hemolysis, with significantly higher levels of lactic dehydrogenase and free plasma hemoglobin and a more pronounced reduction in platelet count were found in the patients perfused with the bubble oxygenator. These differences persisted for 24 hours after the operation; 48 hours after surgery no significant differences between the two groups could be detected. Postoperative blood loss, intra- and postoperative hemodynamics and pulmonary gas exchange were equal in both groups. These results show, that the routine use of membrane oxygenators brings only minor benefits; therefore it may be specially reserved for extended open-heart procedures and for operations in high risk patients.

Use of pancuronium in children with congenital heart disease.

Dosage of pancuronium required to produce 90% neuromuscular blockade, time of onset of action of pancuronium and changes in heart rate and arterial pressure were evaluated in 30 children with congenital cardiovascular disease during intravenous anesthesia. Neuromuscular blockade was measured using train-of-four stimulation (2 Hz for 2 seconds) and twitch count. The 90% blockade was defined as being one twitch felt on the stretched abducted thumb. In 10 children given 0.03- to 0.01-mg/kg increments of pancuronium at 2-minute intervals the mean (+/-SD) dose required to produce 90% neuromuscular blockade was 0.10 +/- 0.02 mg/kg with a range from 0.08 to 0.14 mg/kg. In 20 children given 0.1 mg/kg of pancuronium, 90% neuromuscular blockade was achieved in 4.45 +/- 1.58 minutes. Children less than 2 years of age did not differ from the older children nor did cyanotic children differ from the acyanotic children. There were no significant changes in heart rate or arterial pressure. In one case bigeminy during intubation was seen. No children had tachycardia after pancuronium.

Comparison of nalbuphine and fentanyl anesthesia for coronary artery bypass surgery. Hemodynamics, hormonal response, and postoperative respiratory depression.

To determine whether nalbuphine might replace fentanyl as the principal opioid for anesthesia during coronary artery bypass surgery, 20 patients undergoing myocardial revascularization were anesthetized with flunitrazepam and with a continuous infusion of either nalbuphine (an opioid agonist-antagonist) or fentanyl (a pure opioid agonist) in equipotent dosage ratio of 333:1. During endotracheal intubation, all patients given nalbuphine, but only one given fentanyl (P less than 0.05), required nitroglycerin to control arterial blood pressure. Two minutes after tracheal intubation, plasma values of epinephrine, norepinephrine, vasopressin, and cortisol did not change in the fentanyl group compared with the awake (baseline) levels, whereas catecholamines and vasopressin significantly increased with nalbuphine compared with the baseline and with the values in the fentanyl group. A steady state of anesthesia (30 min after intubation), when compared with the baseline, was characterized by unchanged systemic and pulmonary blood pressures and increased systemic vascular resistance with nalbuphine, by decreased systemic and pulmonary pressures and resistances with fentanyl, and by comparably decreased cardiac index with both opioids. Hormone values returned to baseline levels but norepinephrine remained significantly higher in the nalbuphine than in the fentanyl group. A bolus injection of either nalbuphine (2.5 mg/kg) or fentanyl (7.5 micrograms/kg) given during the steady-state period of anesthesia provoked only minimal hemodynamic changes. Before skin incision, 7 of 10 patients receiving nalbuphine required nitroglycerin to control arterial blood pressure. After sternotomy, both groups required nitroglycerin, but additional antihypertensive drugs were necessary mainly in the nalbuphine group.(ABSTRACT TRUNCATED AT 250 WORDS)

[Clinical application of a supplement to the extracorporal circulation to produce a pulsatile flow (author's transl)]. / Klinische Verwendung eines Zusatzgerätes zur Herz-Lungen-Maschine zur Erzeugung eines pulsierenden Blutflusses.

Two groups of patients with atherosclerotic coronary artery disease, who underwent aortocoronary bypass operation, were perfused with nonpulsatile flow during extracorporeal circulation (ECC) using membrane oxygenators. One group (MO) was used as a control, while for the other group (PAD) a Pulsatile Assist Device in the arterial line was employed. This apparatus consists of a balloon of 80 ml placed inside a rigid housing. The balloon is compressed by pressurized air or expanded by vacuum supplied by a driving console. The apparatus produced pulse amplitudes between 30 and 50 mm of mercury. Other than a very short-lasting fall in mean arterial pressure, thus showing diminished peripheral resistance, no perceptable advantages were found. Base excess and pH-changes showed no differences, also the given amount of sodium bicarbonate in both groups was the same. On the other hand significantly higher hemolyses took place, increasing with the duration of pulsation. The application of the apparatus as an arterial counterpulsator was possible with limitation in only 5 of 15 patients. In all other patients after a short time massive blood foaming developed in the PAD and the attempts had to be stopped because of the risk of gas embolism. In our opinion this apparatus is an unnecessary supplement to the ECC and as an arterial counterpulsator it seems too dangerous.

[Surgical risk in patients over 70]. / Chirurgisches Risiko beim über 70jährigen Patienten.

501 instances of surgery during 1979 in 390 patients aged 70 years or older are reported. The total preoperative mortality rate was 5.4% of operations or 6.9% of patients. Surgery in this patient group was more frequent (1979 11%, 1956/57 8.3%) while the mortality rate had decreased significantly. Urgent operations were frequent (23%), with five times the mortality rate (15%) than for elective operations (2.6%). It is therefore desirable to avoid urgent interventions and operate under elective conditions, though this is not always possible in practice.

[Percutaneous transluminal dilatation of chronic coronary stenoses. First experiences]. / Die perkutane transluminale Dilatation chronischer Koronarstenosen.

The technique of percutaneous transluminal dilatation of coronary artery stenosis consists of a catheter system introduced via the femoral artery under local anesthesia. A preshaped guiding catheter is positioned in the orifice of the coronary artery and through this a dilatation catheter is inserted into the branches if the artery. This dilatation catheter (outer diameter 0.5--1.25 mm) is equipped with a sausage-shaped distensible segment (balloon) at the tip. The balloon is inflated to a pressure of 5 atm. This pressure compresses the atherosclerotic material in a direction perpendicular to the wall of the vessel, therby dilating the lumen. Up to now 29 patients have been treated with primary success in 23 (79%) and long-lasting success in 21 (72%). Three patients underwent emergency coronary surgery to avoid infarction. Dilatation is indicated in patients with disabling angina which jeopardizes their quality of life and with coronary lesions which are proximal, subtotal, concentric and non-calcified.