Extracorporeal membrane oxygenation support for single lung transplantation in a patient with primary pulmonary hypertension

Left single lung transplantation was performed under perioperative extracorporeal membrane oxygenation (ECMO) support for a patient of primary pulmonary hypertension. Continuous ECMO in this patient for one day after the transplantation decreased the pulmonary blood flow and probably served to minimize the potential complication of reperfusion edema of the graft. During this period, the ECMO was gradually weaned so that the grafted lung could adapt itself to the gradually increased blood flow through it. The patient was extubated without difficulty 2 days alter the removal of ECMO and made a smooth recovery.

Stress-reducing effect of physician's tape-recorded support on cardiac surgical patients in the intensive care unit

Staying in an intensive care unit (ICU) is very stressful for patients after heart surgery. Although it is a general belief that support from doctors is important to reduce patients' tension, no quantitative data are available. We investigated the stress-reducing effects of a tape-recorded message from the physician which provided information regarding the surgery and emotional support for heart surgery patients postoperatively in the ICU. Sixty patients who underwent cardiac surgery were randomly allocated to two equal groups. The patients in the experimental group listened to a tape-recorded message from their attending surgeon soon after they recovered from anesthesia, while the control group rested during the study period. The effectiveness of the tape-recorded support program was evaluated by the influence on heart rate, blood pressure, and finger skin temperature, as well as the degree of subjective pain, tension, anxiety, depression, and anger. The pain and tension levels of the patients were measured using a visual analogue scale, while the severity of anxiety, depression, and anger was evaluated using the Brief Symptom Rating Scale. Patients' evaluation of the usefulness of the program was also assessed. After listening to the physician's recorded message, the mean increase in the skin finger temperature in the experimental group was higher than in the control group (0.44 degree C vs 0.25 degree C, p = 0.0513). The experimental group had significant decreases in their mean scores of pain (-1.11 vs 0.36, p = 0.0043), tension (-2.26 vs -0.25, p = 0.0001), anxiety (-1.3 vs -0.57, p = 0.0473), and depression (-2.24 vs -0.37, p = 0.0253). The patients showed a high need for this support program (mean need score 8.4). These findings show that a physician's tape-recorded message providing information and emotional support can reduce stress in heart surgery patients in the ICU postoperatively.

Postpartum myocardial infarction rescued with an intraaortic balloon pump and extracorporeal membrane oxygenator

A 37-year-old woman had postpartum myocardial infarction complicated with cardiogenic shock. The infarction was attributed to diffuse coronary artery spasm caused by methylergonovine, which had been used to treat the postpartum haemorrhage due to placenta increta. The haemodynamics could not be maintained with catecholamine infusion and intraaortic balloon counterpulsation. At last, an extracorporeal membrane oxygenator was used to save her life, and the patient was successfully weaned from the machine 100 h later; she made an uneventful recovery thereafter.

Extracorporeal membrane oxygenation in the perioperative period of heart transplantation

Mechanical circulatory support is occasionally needed in the perioperative period of heart transplantation. Between February and May 1995, three recipients of cardiac transplant at the National Taiwan University Hospital required the use of extracorporeal membrane oxygenation (ECMO) for temporary mechanical circulatory support in the perioperative period of heart transplantation. All three patients received ECMO through the percutaneous femoral veno-arterial route. The ECMO device has a heparin-bound Carmeda Bioactive surface and centrifugal pump. Patient 1 needed ECMO for treatment of a postoperative pulmonary hypertensive crisis. Patient 2 needed ECMO for early cardiac allograft failure, possibly due to ischemia. Patient 3 needed ECMO as a bridge to his first heart transplant after acute myocardial infarction complicated with cardiogenic shock, and again as a bridge to retransplantation because of acute failure of the first cardiac transplant and finally for a temporary circulatory support during rescue treatment for acute vascular rejection of the second cardiac transplant. All three patients were successfully treated with ECMO without major complications. In conclusion, ECMO provides excellent mechanical circulatory support for some situations in the perioperative period of heart transplantation.

Emergency use of extracorporeal membrane oxygenation in a patient with post-cardiotomy myocardial stunning

Myocardial stunning refers to reversible postischemic myocardial dysfunction persisting after reperfusion. We report a patient who presented with biventricular failure, but exhibited neither definite electrocardiographic change nor elevation of serum cardiac enzyme levels in the post-cardiotomy period. The presentation was indicative of myocardial stunning. The patient's hemodynamics could not be maintained even with infusion of high doses of catecholamines. Extracorporeal membrane oxygenation successfully restored myocardial function. In conclusion, when the hemodynamic status of a patient with myocardial stunning cannot be maintained with inotropic agents, extracorporeal membrane oxygenation should be considered.

Extracorporeal membrane oxygenation support for postcardiotomy cardiogenic shock

Extracorporeal membrane oxygenation (ECMO) has had promising results in life-threatening respiratory failure and postcardiotomy cardiogenic failure. From October 1994 to October 1995, 18 patients received 19 ECMOs at National Taiwan University Hospital for severe cardiogenic shock after cardiac surgery. They included patients receiving cardiac massage or repeated bolus injections of norepinephrine to maintain blood pressure (n = 10), patients who could not be weaned off cardiopulmonary bypass after several attempts despite intraaortic balloon pumping and maximal doses of catecholamine (n = 7), and patients with progressive intractable cardiogenic shock after cardiac surgery. Venoarterial ECMO was set up via femoral artery (17 or 19 Fr cannula) and vein (19 or 21 Fr) in all patients except 2 infants. No left heart drainage was performed in any of the patients. The heparin-coated circuit (with Carmeda Bio-active Surface) was used in the last 13 patients to reduce bleeding. Ten (52.6%) of the 19 cases could be smoothly weaned off ECMO, and 6 (33.3%) of the 18 patients were discharged from the hospital in good condition. Four (80%) of the 5 patients after valvular surgery and all 3 heart transplant patients could be weaned off ECMO successfully with the survival rate being 60% and 67%, respectively. Complications included leg ischemia (n = 3), bleeding (n = 4), renal failure (n = 3), and tube rupture (n = 1). The inability to wean off ECMO was caused by multiple organ failure (n = 5), sepsis (n = 2), tube rupture (n = 1), and dysfunction of the ECMO system (n = 1). The major cause of multiple organ failure was hesitation to set up ECMO. Our preliminary results confirmed the effect of ECMO in postoperative cardiogenic shock.

Continuous monitoring of venous oxygen saturation in critically-ill infants

A 4-French gauge Opticath catheter, inserted into a neonate's right atrium through the right internal jugular vein, can be used to continuously monitor venous blood oxygen saturation in the right atrium. This method instantly detects subtle changes in cardiopulmonary function in small infants and neonates and enables the appropriate treatment to be given in cases of critical infantile and neonatal cardiopulmonary deterioration. This report discusses four neonatal and infantile patients who underwent continuous monitoring of venous blood oxygen saturation in the right atrium. Continuous monitoring allowed appropriate treatment to be given earlier compared to conventional monitoring methods of blood pressure and heart rate.

Dietary n-3 polyunsaturated fatty acids and smoking-related chronic obstructive pulmonary disease. Atherosclerosis Risk in Communities Study Investigators

BACKGROUND

Fish contain n-3 polyunsaturated fatty acids, principally eicosapentaenoic acid and docosahexaenoic acid, which are known to interfere with the body's inflammatory response and may be of benefit in chronic inflammatory conditions.

METHODS

We studied the relation between the dietary intake of n-3 fatty acids and chronic obstructive pulmonary disease (COPD) in 8960 current or former smokers participating in a population-based study of atherosclerosis. Intake of fatty acids was estimated with a dietary questionnaire. The presence of COPD was assessed by a questionnaire on respiratory symptoms and by spirometry. Three case definitions of COPD were used: symptoms of chronic bronchitis (667 subjects), physician-diagnosed emphysema reported by the subject (185 subjects), and spirometrically detected COPD (197 subjects).

RESULTS

After control for pack-years of smoking, age, sex, race, height, weight, energy intake, and educational level, the combined intake of eicosapentaenoic acid and docosahexaenoic acid was inversely related to the risk of COPD in a quantity-dependent fashion. The adjusted odds ratio for the highest quartile of intake as compared with the lowest quartile was 0.66 for chronic bronchitis (95 percent confidence interval, 0.52 to 0.85; P < 0.001 for linear trend across the range of intake values), 0.31 for physician-diagnosed emphysema (95 percent confidence interval, 0.18 to 0.52; P for linear trend, 0.003), and 0.50 for spirometrically detected COPD (95 percent confidence interval, 0.32 to 0.79; P for linear trend, 0.007).

CONCLUSIONS

A high dietary intake of n-3 fatty acids may protect cigarette smokers against COPD.

A new dosing regimen for esmolol to treat supraventricular tachyarrhythmia in Chinese patients

OBJECTIVES

The purpose of this study was to find a safe dosing regimen for esmolol infusion to rapidly control supraventricular tachyarrhythmia after cardiac surgery in Chinese patients.

BACKGROUND

Tachycardia increases cardiac work but reduces myocardial perfusion. Thus, in the critical period immediately after cardiac surgery, tachycardia itself warrants urgent intervention. Esmolol, an ultrashort-acting beta-adrenergic blocking agent, has been reported in western published reports to have good results and few side effects in the treatment of supraventricular tachyarrhythmia. However, its clinical application in Chinese patients has not yet been reported.

METHODS

When supraventricular tachyarrhythmia with a rapid ventricular response (> 110/min) was found early after cardiac surgery, esmolol infusion with a different dosing regimen was used to control the tachyarrhythmia.

RESULTS

With the dosing regimen recommended in western published reports (repeated loading infusion with stepwise increment), acute hypotension with systolic pressure < 80 mm Hg occurred in all six patients after 1 min of loading infusion of esmolol (500 micrograms/kg body weight per min). To avoid the aforementioned complications, a new dosing regimen was constructed. The initial infusion rate of esmolol was set at 150 or 100 micrograms/kg per min, depending on the patient's age and blood pressure. When the desired heart rate was achieved, the initial infusion rate was reduced to the maintenance infusion rate to maintain the therapeutic effect [Maintenance infusion rate = Initial infusion rate x (1 - e-0.077t), where t is the time period in minutes required by the initial infusion of esmolol to achieve the therapeutic effect]. With this new dosing regimen, tachycardia in most patients (9 of 11) could be controlled within 10 min, and no one experienced the side effect of hypotension. The maintenance infusion rate of esmolol needed to control supraventricular tachyarrhythmia in our patients was only 73 +/- 42 micrograms/kg per min (mean +/- SD), much less than that noted in western reports.

CONCLUSIONS

The dosing regimen for esmolol infusion recommended in western studies is not suitable for Chinese patients. In this report we propose a new dosing regimen for esmolol infusion that is both safe and rapid in the treatment of supraventricular tachyarrhythmia in Chinese patients.

A computer-enhanced comparative study of brain region polypeptides and proteins by two-dimensional gel electrophoresis

A reproducible and quantitative strategy for identifying tissue-specific proteins of the central nervous system is described. The methods include a simple extraction procedure, two-dimensional polyacrylamide gel electrophoresis (2-DGE), silver staining, and computerized analysis. Acetic acid protein extractions of brain regions from three groups of male Sprague-Dawley rats were compared by computer analysis using 2-DGE with GELCODE silver staining. Protein spot mapping and characterizations of molecular weight and pI were compiled for the pineal gland, retina, hypothalamus and cerebral cortex. Regionally specific protein spots were identified using the Visage System (BioImage) for data acquisition and a new set of algorithms (University of Arizona) for assigning isoelectric point (pI) and molecular weight determinations, spot matching and selection of unique spots. Seventeen newly identified acidic proteins are unique to the pineal gland. Some others are also common to the retina but not in other regions examined. Further study of these and other regionally specific proteins are of particular interest under conditions which alter biological or disease mechanisms.