Gastrointestinal complications after cardiac surgery

OBJECTIVE: Gastrointestinal (GI) complications after cardiac surgery with cardiopulmonary bypass (CPB) are uncommon complications with significant morbidity and mortality rates. METHODS: From 1988 to 1995, 36 GI complications were identified in 3158 patients who underwent cardiac surgery (1.14% incidence). The mortality rate was 13.9%. Complications included hemorrhage in the GI tract in 22, perforated ulcer in 3, acute cholecystitis in 3, pancreatitis in 2, mesenteric ischemia in 3, diverticulitis in 1 and liver failure in 2 patients. RESULTS: Clinical risk factors included advanced age, combined coronary artery bypass grafting (CABG)-valve operation, postoperative low cardiac output (LCO), prolonged ventilation time, re-exploration of the chest, sternal infection and a positive history of peptic ulcer. Patients with a prolonged pump time had an increased risk of GI complications (P < 0.001). CONCLUSIONS: Gastrointestinal complications, although of low incidence, carry a significantly high mortality, and the clinician must be alert to institute early appropriate treatment.     

Quality of life after cardiac surgery

Tremendous strides have been made in the surgical treatment of cardiac disease. Research has documented many physical and psychologic benefits for the patient, but many questions remain unanswered. The change in quality of life may be the single most important outcome of cardiac surgery. This issue has received considerable attention in professional literature in recent years, particularly in the midst of rapidly expanding technology and soaring health care costs. This article reviews the literature related to the quality of life of cardiac surgical patients. Specific topics, such as physiologic and psychologic outcomes, return to work, family responses, and issues related to transplant patients, are discussed. The article includes a discussion of nursing implications.     

Syncope in bradycardic cardiac arrhythmias

Bradyarrhythmias, depending on the patient population, are the cause of syncope in 3 to 10%. Marked bradycardia or asystole can be due to impaired function of the sinus node (sinus node syndrome) or high-grade AV-conduction block as well as carotid sinus syndrome and pathologic vasodepressor reactions. In particular, in the presence of high-grade AV-block, the diagnosis of bradyarrhythmia-induced syncope can frequently be established on the basis of a standard ECG. One of the most common causes of syncope is functional impairment of the sinus node, in particular, an inadequate permanent sinus bradycardia, sinus node arrest or SA-block and paroxysmal atrial tachycardia alternating with atrial bradycardia. The method of choice for detecting suspected paroxysmal arrthythmias is ambulatory ECG monitoring but interpretation may be encumbered by the absence of concomitant symptoms during the registration. Frequently, the use of non-invasive methods alone, such as detailed history, ambulatory ECG and ECG exercise testing, will not render confirmatory findings to document the cause of syncope, that is, > 3 s pause in sinus rhythm or high-grade AV-block. In this situation, the question arises which patients should undergo electrophysiologic examination. Several studies have shown that in patients with a pathologic resting ECG (first degree AV-block, bundle branch block, inadequate sinus bradycardia) and cardiac disease, electrophysiologic studies will document a cause of syncope in more than 30%.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cellular electrophysiologic mechanisms of cardiac arrhythmias

Cardiac arrhythmias are caused by alterations in the electrophysiologic properties of the cardiac cells, which affect the characteristics of the transmembrane potentials. The electrophysiologic properties that cause arrhythmias are automaticity, triggered activity, and reentrant excitation. Each of these mechanisms is described in terms of the characteristics of the transmembrane potentials and how these influence the appearance of the arrhythmia on the electrocardiogram.     

Drug therapy of cardiac arrhythmias 199

Current antiarrhythmic drug therapy is employed in strict compliance with the proper indication, which is itself limited by the side effects of the available drugs, and modified by the increasing success of such non-drug options as electrical ablation and implantable cardioverters/defibrillators. Drug treatment is restricted to 3 major indications, regular paroxysmal supraventricular tachycardias, atrial flutter and fibrillation, and ventricular tachycardias. Class IA and IC agents are used only to treat supraventricular and ventricular arrhythmias with no structural heart disease. Class III drugs, e.g. sotalol and in particular amiodarone are used preferentially to treat the pre-damaged heart, in particular left-ventricular functional impairment and in coronary heart disease in consideration of their side effects. In the case of the most common treatment-requiring arrhythmia-atrial fibrillation-anticoagulation alone may be indicated. For the prevention of sudden death, beta-blockers continue to be the drugs of first choice.     

Self-report of cognitive function after cardiac surgery.

Surveyed 143 patients 2–3 yrs after cardiac bypass graft and valve replacement procedures concerning their complaints of cognitive (CG) impairment. Ss completed a survey of everyday CG problems and answered specific questions about their lifestyle, general health, cardiac risk factors, surgery, and recovery. 110 Ss completed the CG Behavior Rating Scale. Ss did not endorse CG problems following cardiac surgery. Results suggest that Ss experience psychological distress after surgery and that this distress is partially expressed in the form of complaints about mild memory loss and cognitive inefficiency. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hyperamylasemia after cardiac surgery in infants and children

OBJECTIVE: This study was conducted to clarify the incidence of hyperamylasemia after cardiac surgery in infants and children. DESIGN AND PATIENTS: 186 infants and children operated on at Children's Hospital. Helsinki, during an 11-month period were enrolled in the study. Serum samples were taken before and on 3 consecutive days after cardiac surgery at the intensive care unit and before discharge from the hospital. MEASUREMENTS: We measured serum total amylase and serum pancreatic amylase with two different assays (1) reduction of salivary amylase from total amylase activity and (2) measurement of mass concentration with monoclonal antibodies. RESULTS: Preoperative values for both total amylase and pancreatic isoenzymes were strongly age-related. At least one of the three tests showed postoperative hyperamylasemia (> +/- 2 SD above starting values of the age group and maximal value > 3 times the individual starting value) in 64/186 (34%) patients. 22/186 (12%) patients had abnormal results in all assays. A more than tenfold rise in pancreatic amylase, suggesting pancreatitis, was found in 14 patients (8%). Mortality was 21% in this subgroup, but 5% in the rest of the patients. Hyperamylasemia was more common after 1 year of age, and after open-heart surgery, especially homograft implantation or cardiac transplantation. CONCLUSIONS: Hyperamylasemia is a common finding after cardiac surgery in pediatric patients. Amylase isoenzyme measurements are needed for clinical decision making. Age-group-related reference values are mandatory for the right interpretation of amylase values.     

Late posterior cardiac tamponade after open heart surgery

OBJECTIVE: Late cardiac tamponade after open heart surgery is a relatively uncommon, but potentially serious complication. We retrospectively analyzed 14 patients who had posterior cardiac tamponade 13 to 210 days after open heart surgery. PATIENTS: Between May 1988 and July 1995, 3150 adult patients underwent open heart surgery at the Gülhane Military Medical Academy. In 35 of 3150 patients (1.11%) late pericardial effusions developed, and in 14 (0.44% of 3150 consecutive open heart surgery performed on adult patients in our center) of these patients had posterior tamponade. There were moderate symptoms including fatigue, malaise, and dyspnea on exertion in all patients. The diagnosis was made by echocardiography in 13 patients, and by tomographic scanning in 1 patient. Analysis of these 14 patients revealed that all of them had hemodynamic criteria consistent with tamponade physiology on right heart catheterization with Swan-Ganz catheters. RESULTS: Echocardiography guid pericardiocentesis through the left anterior axillary line was effective in decompressing of posterior cardiac tamponade in 10 of 14 patients. Three patients required operative surgical drainage after unsuccessful pericardiocentesis through subxiphoid area. Two patients who underwent surgical drainage died, and in one patient surgical pericardiotomy had complete evacuation of posterior pericardial fluid with major complication. CONCLUSIONS: 2-D echocardiography guid pericardiocentesis through left anterior axillary line was found to be a useful, safe, and simple technique. It can be used as an alternative treatment to surgical pericardiotomy for posterior cardiac tamponade after open heart surgery.     

Mechanical assistance in cardiogenic shock after cardiac surgery

With [14C]oleate-labeled phosphatidylcholine as a substrate for phospholipase D the hydrolytic activity was measured by phosphatidic acid formation and the transphosphatidylation activity was measured by the phosphatidylethanol formed in the presence of ethanol. The pH optimum was 6.5 with dimethylglutarate as the buffer. EGTA inhibited the transphosphatidylation activity to a greater extent than the hydrolytic activity. In contrast CaCl2, BaCl2, MgCl2 and SrCl2 stimulated the hydrolytic activity without effecting the transphosphatidylation activity. BeCl2 another member of the group IIa transition metals was a very potent inhibitor of both the hydrolytic and transphophatidylation activity. GTP gamma S, an activator of G protein-mediated events, was an inhibitor of both activities.     

Recognition and management of childhood cardiac arrhythmias

Axonal connections between the amygdala and the hypothalamic paraventricular nucleus were examined by combined anterograde-retrograde tract tracing. Iontophoretic injections of the retrograde tracer Fluorogold were placed in the paraventricular nucleus, and the anterograde tracer PHA-L in the ipsilateral central or medial amygdaloid nuclei. Single and double-label immunohistochemistry were used to detect tracers. Single label anterograde and retrograde tracing suggest limited evidence for direct connections between the central or medial amygdala and the paraventricular nucleus. In general, scattered PHA-L-positive terminals were seen in autonomic subdivisions of the paraventricular nucleus (lateral parvocellular, dorsal parvocellular and ventral medial parvocellular subnuclei) following central or medial amygdaloid nucleus injection. Double-label studies indicate that central and medial amygdaloid nucleus efferents contact paraventricular nucleus-projecting cells in several forebrain nuclei. In the case of central nucleus injections, PHA-L positive fibers occasionally contacted Fluorogold-labeled neurons in the anteromedial, ventromedial and preoptic subnuclei of the bed nucleus of the stria terminalis. Overall, such contacts were quite rare, and did not occur in the bed nucleus of the stria terminalis regions showing greatest innervation by the central amygdaloid nucleus. In contrast, medial amygdala injections resulted in a significantly greater overlap of PHA-L labeling and Fluorogold-labeled neurons, with axosomatic appositions observed in medial divisions of the bed nucleus of the stria terminalis, anterior hypothalamic area and preoptic area. The results provide anatomical evidence that a substantial proportion of amygdaloid connections with hypophysiotrophic paraventricular nucleus neurons are likely multisynaptic, relaying in different subregions of the bed nucleus of the stria terminalis and hypothalamus.     

Point-of-care (POC) measurement of coagulation after cardiac surgery

Infection of feline immunodeficiency virus (FIV) has been shown to induce apoptosis that might be associated with the lymphocyte depletion in the infected cats. To investigate the inhibitory effect of antioxidants on FIV-induced apoptosis, we examined the effect of N-acetylcysteine (NAC) and ascorbic acid (AA) on apoptosis and virus replication in feline lymphoblastoid (Fel-039) and fibroblastoid (CRFK) cell lines infected with FIV. The treatment with NAC or AA induced a significant inhibition of viral replication and apoptosis in Fel-039 cells and tumor necrosis factor alpha (TNF-alpha)-treated CRFK cells infected with FIV. Both cell lines in the presence of noncytotoxic concentrations of NAC or AA showed in increase of intracellular glutathione (GSH) level, which might protect the cells against oxidative stresses exerted by FIV infection and TNF-alpha treatment. On the basis of these in vitro results, we suggest that antioxidant therapies aimed at restoring depleted GSH level might be effective for inhibition of viral replication and cell death associated with the development of immunodeficiency.     

Effectiveness of digitalis with or without acebutolol in preventing atrial arrhythmias after coronary artery surgery

In this study, a beta-adrenergic blocker in combination with digoxin provided marginal protection against atrial fibrillation/flutter after coronary artery surgery. The economic comparison of patients who did and did not develop atrial fibrillation/flutter indicates that prevention of these arrhythmias can have a significant impact on length of hospital stay and cost of this common surgical procedure.