PubMed Health⌕ Search

Biomedical subjects

S Reiz

Publications and source records attributed to S Reiz.

At least 73 records · Page 4Linked to original sources

Fibrinolytic activity in plasma and deep vein thrombosis after major abdominal surgery.

In a prospective study of the frequency of deep vein thrombosis (DVT) in 45 patients subjected to major abdominal surgery, 17 patients showed signs of DVT as assessed by the 125I-fibrinogen test. In 15 of the patients the DVT was diagnosed during the first four postoperative days. Blood samples were taken pre- and postoperatively and analysed for fibrinogen, prothrombin complex, APTT, platelet-count, plasminogen, alpha 2-antiplasmin, fibrin(ogen) degradation products, and plasmin-alpha 2-antiplasmin complex (PAP). The latter was used in order to reflect the fibrinolytic activity. Preoperatively, and postoperatively on day 3, the levels of PAP were significantly higher in patients without postoperative DVT. The data suggests that patients subjected to major abdominal surgery, who have enhanced fibrinolytic activity preoperatively, have a lesser tendency to develop postoperative DVT. Patients with postoperative DVT may have decreased fibrinolytic ability. From the data of the other parameters it is concluded that patients with DVT can have increased levels of FDP at the time of development of thrombosis.

Abdomen↗

Effects of enflurane-nitrous oxide anaesthesia and surgical stimulation on regional coronary haemodynamics in a patient with LAD bypass graft.

Central and regional coronary haemodynamics were studied in a patient with a left anterior descending artery (LAD) graft and angiographically visible collaterals from a normal right coronary artery. A three-thermistor thermodilution catheter was used for measuring total coronary sinus blood flow and great cardiac venous blood flow, the latter being a good representative of blood flow through the LAD. Enflurane-nitrous oxide anaesthesia induced marked coronary vasodilatation and redistribution of blood flow from the LAD to other areas draining into the coronary sinus. The most likely mechanism for the redistribution of blood flow in this patient was steal via the collaterals between the LAD and the right coronary artery. During surgical stimulation, the flow through the LAD was further compromised due to pronounced coronary vasoconstriction, probably mediated by catecholamine release.

Anesthesia, General↗

Nitrous oxide augments the systemic and coronary haemodynamic effects of isoflurane in patients with ischaemic heart disease.

The effects of 70% nitrous oxide, added to 1% end-tidal isoflurane and administered by intermittent positive pressure ventilation (IPPV), on coronary haemodynamics and myocardial oxygenation were investigated in 10 patients with ischaemic heart disease. Standard methods were used for determination of their central haemodynamic effects. Coronary blood flow was measured by the retrograde thermodilution technique and coronary sinus blood sampled for measurement of myocardial oxygen consumption and lactate extraction. One per cent end-tidal isoflurane decreased systemic blood pressure (-39%) by a combination of systemic vasodilation and reduction in cardiac performance. Coronary blood flow remained unaltered despite the fall in coronary perfusion pressure and myocardial oxygen consumption (-30%) and extraction (-30%) fell significantly. Ischaemic ECG changes parallelled by decreased myocardial lactate extraction or lactate production were recorded in 6 of the 10 patients during steady state isoflurane anaesthesia. When nitrous oxide was added to isoflurane there was a fall in heart rate (-13%), a further reduction in systemic blood pressure (-18%) and myocardial oxygen consumption (-31%) and extraction (-17%) whereas all other variables including coronary blood flow remained unaltered. The myocardial ischaemia was worsened in three of the six patients with ECG and metabolic signs of impaired oxygenation during isoflurane alone. It is concluded that nitrous oxide potentiates the systemic and coronary haemodynamic effects of isoflurane in patients with coronary artery disease. The mechanisms for myocardial ischaemia seem to be decreased coronary perfusion pressure and/or redistribution of coronary blood flow by direct coronary vasodilation.

Aged↗

Topical anaesthesia with EMLA, a new lidocaine-prilocaine cream and the Cusum technique for detection of minimal application time.

The minimal effective onset time of the new topical anaesthetic formulation EMLA (a eutectic mixture of lidocaine and prilocaine), was evaluated by the double-blind technique in 53 female and 66 male patients (median age 40 and 36 years, respectively) subjected to intravenous cannulation. Conventional plotting and regression analysis failed to answer the question. The Cusum technique, originally designed for industrial production control, could successfully be applied to solve the problem. It demonstrated a minimal effective EMLA application time of 45 min in adults.

Administration, Topical↗

In vitro analysis of thermal transport in coronary sinus thermodilution catheters.

The continuous thermodilution technique for measuring blood flow in the range 50-300 ml/min was evaluated in vitro. Experiments indicated that thermotransport within the catheter from the indicator line to the mixing thermistor exists. The resulting error in calculated thermodilution flow will increase with increasing flow rate. A correction factor for thermal transport, Ft, obtained from a blood circulation model was incorporated in a modified formula for calculation of thermodilution flow. Flows derived with the standard Ganz formula were significantly lower than timed volumetric flows, whereas flows obtained with the modified formula agreed with volumetric flow. The coefficient of variation for four consecutive measurements was 3.4%.

Blood Flow Velocity↗

Effects of indomethacin on central, renal and coronary hemodynamics. An experimental study in swine with unilateral ureteral obstruction.

The circulatory effects of intravenously administered indomethacin, a potent prostaglandin synthesis inhibitor (0.8 mg/kg bw) were investigated in pigs with unilateral ureteral obstruction. The drug induced a marked but transient increase in systemic arterial pressure (+53%, p less than 0.02) and pulmonary arterial (+81%, p less than 0.02) pressure without any changes in left or right sided filling pressures, cardiac output or heart rate. Coronary blood flow remained unchanged and renal venous blood flow decreased (-26%, p less than 0.02). Renal pelvic pressure decreased (-20%, p less than 0.02). Thus systemic (SVR), pulmonary (PVR) and coronary vascular resistance (CVR) and renal vascular resistance (RVR) on the obstructed side increased (SVR + 73%, p less than 0.02; PVR + 140%, p less than 0.02; CVR + 53%, p less than 0.02 and RVR + 107%, p less than 0.02 respectively). Even if one takes into consideration other factors than ureteral obstruction contributing to these reactions, e.g. low volume load, anaesthesia, surgical trauma and species differences, care is advised in treating patients with coronary artery disease or obstructive lung disease with indomethacin.

Animals↗

Thromboembolic complications after major abdominal surgery: effect of thoracic epidural analgesia.

In a prospective study of 50 patients subjected to major abdominal surgery, the frequencies of postoperative deep vein thrombosis and pulmonary embolism were analysed. The patients were randomized to one of two groups receiving either neurolept anaesthesia or neurolept anaesthesia combined with thoracic epidural analgesia. Five patients were excluded. No special anti-thrombotic prophylaxis was administered. Deep vein thrombosis was diagnosed with the 125I-fibrinogen test and pulmonary embolism with pre- and postoperative lung perfusion scintigraphy combined with lung X-ray. Patients with positive scintigraphy were subjected to pulmonary angiography for verification of the diagnosis. Deep vein thrombosis was treated when diagnosed. The frequency of deep vein thrombosis was equal in both groups (38%). No patient with pulmonary embolism was recorded during the first seven days after operation. It is concluded that the addition of thoracic epidural analgesia to neurolept anaesthesia does not alter the postoperative frequency of deep vein thrombosis in patients subjected to major abdominal surgery. Early diagnosis and treatment of postoperative deep vein thrombosis might prevent pulmonary embolism. Problems encountered in the diagnosis of postoperative pulmonary embolism are discussed.

Abdomen↗

Droperidol inhibits the effects of intravenous ketamine on central hemodynamics and myocardial oxygen consumption in patients with generalized atherosclerotic disease.

A 2-mg/kg dose of ketamine was administered intravenously to 16 patients with generalized atherosclerotic disease. Eight patients were given 200 mu/kg of droperidol intravenously 10 min before ketamine administration; eight patients not given droperidol served as controls. Central hemodynamics, coronary flow (thermodilution technique) and myocardial oxygen, lactate, hypoxanthine, and catecholamine balances were studied. In control patients, ketamine increased mean blood pressure by 42%, pulmonary capillary wedge pressure by 144%, mean right atrial pressure by 60%, heart rate by 15%, and systemic vascular resistance by 40% without changes in cardiac index, stroke volume index, or left ventricular stroke work index. These data indicate that cardiac performance did not increase in parallel with the rise in afterload. However, the 50% increase in myocardial oxygen demand was associated with a 48% increase in coronary blood flow without changes in coronary vascular resistance or myocardial oxygen extraction. Augmented sympathetic activity was manifested by 397% and 164% increases in plasma levels of epinephrine and norepinephrine, respectively. The hemodynamic and cardiometabolic effects of ketamine were abolished when patients were pretreated with droperidol. The increase in plasma epinephrine levels was likewise inhibited by droperidol; significantly lower plasma norepinephrine levels also were observed. These findings suggest that droperidol inhibits the cardiovascular effects of ketamine by a centrally mediated reduction in sympathetic activity and by peripheral alpha receptor blockade.

Adult↗

Haemodynamic effects of intravenously administered prenalterol in patients with severe heart failure.

The acute haemodynamic effects of prenalterol 75-225 micrograms/kg i.v. were studied at rest and during exercise in the supine position in 12 patients with chronic congestive heart failure secondary to myocardial infarction (6 pts), chronic valvular disease with valvular replacement (4 pts), ischaemic cardiomyopathy (1 pt) and post myocarditis (1 pt). In 5 of the 6 AMI patients the effect of prenalterol on myocardial oxygen consumption at rest was measured. Pulmonary artery end-diastolic pressure decreased significantly from 17 to 10 mm Hg at rest and from 31 to 21 mm Hg during exercise. Resting heart rate increased from 78 to 90 at rest but was unchanged during exercise. MVO2 in the 5 patients was unchanged or lower in 4 patients and increased in one in whom angina developed after prenalterol. In general, dyspnoea and angina during exercise were less pronounced after prenalterol. The calculated triple product was lower after prenalterol, especially during exercise, indicating lower myocardial oxygen consumption and probably less myocardial ischaemia.

Adrenergic beta-Agonists↗

Effects of halothane on coronary haemodynamics and myocardial metabolism in patients with ischaemic heart disease and heart failure.

Halothane was administered at an end-tidal concentration of 1% to 10 patients with stable ischaemic heart disease and clinical and haemodymanic signs of moderate heart failure. Measurements of central haemodynamic variables, coronary sinus blood flow and oxygen, lactate and hypoxanthine balances over the myocardium were done before and at steady state during halothane anaesthesia. Halothane induced marked haemodynamic changes with decreases in mean arterial pressure (-43%), mean pulmonary arteriolar occlusion pressure (-42%), systemic vascular resistance (-31%), cardiac index (-20%) stoke volume index (-31%) and left and right stroke work indices (-62% and -55%, respectively). Heart rate and pulmonary vascular resistance did not change. Coronary sinus blood flow decreased in parallel with perfusion pressure, and myocardial oxygen consumption decreased (-40%), as did myocardial oxygen extraction. Rate pressure product and triple product correlated better with changes in myocardial oxygen consumption in the present subset of patients than in healthy volunteers during halothane anaesthesia. The findings suggest that halothane, through its systemic vasodilatory effect, unloads the failing left ventricle and that this peripheral action predominates over the direct cardiodepressant action of the agent. The combined findings of unchanged coronary vascular resistance, decreased myocardial oxygen extraction and absence of increasing or pathological levels of lactate and hypoxanthine in coronary sinus blood imply a direct dilatory effect of halothane on the coronary vasculature.

Aged↗

Beta-blockers and thoracic epidural analgesia. Cardioprotective and synergistic effects.

Seven groups of patients with and without hypertension or with ischaemic heart disease, treated with different beta blockers were investigated to study the circulatory effects of neurolept anaesthesia alone or combined with thoracic epidural analgesia from T4 to T12/L2 during abdominal surgery. The combination of thoracic epidural analgesia and neurolept anaesthesia in hypertensive subjects treated with non-cardioselective beta blockers induced slightly lower blood pressure than measured in similar patients on cardioselective beta blockers with neurolept anaesthesia only. Patients on non-selective beta blockers with intrinsic stimulatory activity (ISA) had higher blood pressure and heart rate after neurolept anaesthesia induction than patients on cardioselective blockers. During surgery, heart rate remained at a higher level in the patients treated with ISA blockers, whereas blood pressure increased to the same level as in patients with cardioselective blockers. Cardiovascular stability was, however, best maintained in the epidural group, where myocardial energy expenditure during maximal surgical stress was comparable to that in a group of healthy subjects with the same format of anaesthesia and significantly lower than in healthy subjects with neurolept anaesthesia alone. No circulatory side effects of the combination of thoracic epidural analgesia and beta blockade were seen. In patients with ischaemic heart disease, with or without non-selective beta blockade, similar haemodynamic changes were recorded following neurolept anaesthesia. During maximal surgical stress, unmasking of alpha adrenergic activity with marked rise in blood pressure was seen in the beta-blocked patients. Despite the more accelerated haemodynamic changes in the blocked patients, a lower increase in myocardial oxygen consumption was recorded compared with the non-blocked patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-Antagonists↗

Hemodynamic effects of flexible fiberoptic bronchoscopy performed under topical anesthesia.

Central hemodynamics and blood gases were measured continuously during flexible fiberoptic bronchoscopy performed under topical anesthesia in ten patients with restrictive lung disease. The procedure induced marked hemodynamic changes, which were maximal and similar in magnitude, during passage through the larynx and during suctioning. Mean arterial pressure increased by 30 percent, heart rate by 43 percent, cardiac index by 28 percent and mean pulmonary arteriolar occlusion pressure by 86 percent compared with pre-bronchoscopic control values. A slight fall in arterial oxygen tension was measured during bronchial suctioning and in the post-bronchoscopic period. Rate pressure product reached its highest value during bronchial suctioning at which time three of the ten patients developed ST-T-segment changes, implying that myocardial oxygen demand might have exceeded supply. It is suggested that the major mechanism behind the hemodynamic changes is a reflex sympathetic discharge caused by mechanical irritation of larynx and bronchi.

Aged↗

The continuous thermodilution method for measuring high blood flows.

The continuous thermodilution method for the measurement of blood flow from 300 to 1500 ml/min was evaluated in vitro and in vivo. In vitro experiments indicated that thermotransport within the catheter, causing a temperature measurement error, can occur. Flow model measurements were used for consequent modification of the original thermodilution formula for calculation of flow. In the in vivo investigations the thermodilution and electromagnetic methods were compared for measurement of pig portal blood flow. Using the modified formula for the flow calculations, good agreement was found between the two methods (r = 0.958). For the continuous thermodilution method in vivo the standard deviation of a single measurement was 19 ml/min and the coefficient of variation 1.6%.

Animals↗

Clinical results with prenalterol in patients with heart failure.

The hemodynamic effect of 75 to 225 microgram/kg prenalterol (PNL) intravenously were studied at rest and during exercise in eight patients with chronic congestive heart failure (CHF) after myocardial infraction (three patients), valvular surgery (three patients), and congestive cardiomyopathy (two patients). All head New York Health Association functional class III and IV CHF and were receiving digitalis and diuretics. With PNL at rest, left ventricular filling pressure (LVFP) fell from 17 to 12 mm Hg, cardiac index (CI) rose from 2.1 to 2.9 L/min/m2, heart rate (HR) increased mildly, systemic vascular resistance (SVR) declined moderately, and peripheral arterial pressure was unchanged. During PNL exercise compared with control, LVFP rise was less and CI, HR, and SVR responses were similar; dyspnea and angina were reduced in most patients. The eight patients were than given PNL orally, 30 to 200 mg/day, versus placebo for 6 days with comparative evaluation by echocardiogram, systolic time intervals (STI), exercise test, and continuous ECG. With PNL orally five of eight patients improved symptomatically, ejection fraction increased from 0.44 to 0.53, and STI preejection period shortened by 10 msec, without change in resting HR or systemic arterial blood pressure. The incidence of ventricular premature beats was not increased. PNL orally vs placebo exercise capacity increased 10%. Thus PNL may be of value for long-term CHF treatment in addition to conventional therapy.

Administration, Oral↗

Effects of thiopentone on cardiac performance, coronary hemodynamics and myocardial oxygen consumption in chronic ischemic heart disease.

Thiopentone was administered as induction agent for general anesthesia to eight patients with stable ischemic heart disease; 6 mg/kg of the drug induced decrease in arterial blood pressure (-27%), systematic vascular resistance (-20%), stroke volume index (-14%), mean pulmonary arteriolar occlusion pressure (-15%) and left ventricular stroke work index (-38%), while heart rate increased by 10% and cardiac output remained unchanged. Total body oxygen consumption decreased by 30%. Myocardial oxygen consumption decreased by 39% with unchanged or decreased myocardial oxygen extraction and myocardial lactate uptake decreased by 40%. Arterial and coronary sinus hypoxanthine levels were unchanged and no ST-T-segment changes or dysrhythmias were recorded. In the present experimental setting, the results indicate that thiopentone substantially decreased myocardial oxygen requirements. In spite of the marked reduction in coronary perfusion, myocardial oxygen demand was matched by supply, myocardial dysoxia was not induced and cardiodepression was clinically negligible. Rate pressure product was a poor indicator of changes in myocardial oxygen consumption after thiopentone administration.

Aged↗

Epidural morphine for postoperative pain relief.

Thirty-three patients were randomly assigned to two groups to study the analgesic potency, duration of action and side effects of epidural and intramuscular morphine after hip surgery. Two milligrams of preservative-free morphine chloride in 10 ml of normal saline in the epidural space was compared to 10 mg of intramuscularly administered morphine. There was a more rapid onset of action after intramuscular morphine. However, the quality of pain relief was substantially higher and the duration of action markedly longer after epidural morphine. The total dose required in the epidural group was 3.6 mg and in the intramuscular group 41 mg during the 15-h observation period. The side effects of epidural morphine were few and mild, the most embarrassing being urinary retention (20%). Nausea and/or vomiting was less common after epidural morphine (20% versus 55%). Pruritus or respiratory depression which have been reported previously were not encountered. However, it is recommended that preservative-free solution are used to avoid itching and that the patients are monitored, as respiratory depression may occur long after administration of epidural opiate.

Aged↗

Non-cardiogenic pulmonary oedema. A serious complication of transurethral prostatectomy. A case report.

A patient undergoing prostatectomy under epidural analgesia developed clinical signs of a severe TURP syndrome. During resuscitation, it was revealed that serum sodium was only moderately decreased. Plasma oncotic pressure was, however, markedly decreased and the pressure gradient between plasma oncotic pressure and pulmonary capillary wedge pressure (approximately hydrostatic pressure) was 1 mmHg (0.13 kPa) only, allowing almost free filtration of fluid through the pulmonary capillary wall, resulting in a non-cardiogenic pulmonary edema. The patient was successfully resuscitated with albumin and inotropic stimulation with prenalterol.

Aged↗