Reliability of an intravenous intermittent access port (saline lock) for obtaining blood samples for coagulation studies.

BACKGROUND: Patients admitted to rule out myocardial infarction often receive a heparin infusion that requires measurement of partial thromboplastin time every 6 to 8 hours until coagulation values stabilize. If the patient's acuity at admission does not necessitate placement of arterial or central catheters, insertion of an intermittent intravenous access port (saline lock) would decrease the need for frequent venipuncture. Many studies on obtaining blood samples via arterial and central catheters have been reported, but no reports have described the method of using a saline lock or the amount of blood discarded during that procedure. OBJECTIVE: To evaluate the efficacy of inserting a saline lock specifically for obtaining blood samples and to determine the amount of blood that must be discarded in order to obtain prothrombin and partial thromboplastin times that match the values from blood samples obtained via venipuncture. METHODS: Coagulation values determined with 2 consecutive blood samples obtained via the saline lock after the first 0.5 mL of blood withdrawn was discarded were compared with measurements determined with a blood sample obtained via venipuncture. RESULTS: Prothrombin and partial thromboplastin times were not significantly different among the 3 blood samples. CONCLUSION: The untoward effects of frequent venipunctures to obtain blood samples for measurement of prothrombin and partial thromboplastin times can be lessened by using an 18-gauge saline lock to obtain blood samples and discarding the first 0.5 mL of blood withdrawn before the samples for coagulation studies are collected.

Simplified method for candidate selection for radial artery harvesting.

With the renewed interest in the use of autogenous radial arteries in coronary artery bypass grafting, concerns regarding vascular compromise and selection of patients have arisen. In this report, we describe a modification of Allen's test.

Hyperinsulinemia and cardiovascular risk.

Tissue insulin resistance and compensatory hyperinsulinemia cause early atherosclerosis and an increased cardiovascular risk for the non-insulin dependent diabetic individual. Evidence now indicates that a large and likely unrecognized number of individuals are insulin resistant and hyperinsulinemic and therefore share this risk. Ongoing investigation of this phenomenon may produce changes in the methods for earlier identification of these individuals and in the treatment of obesity, diabetes, and cardiovascular disease and may expand the areas in which nursing intervention can alter outcome.

Surgery for angina pectoris--historical aspects.

The history of surgery for ischemic heart disease is presented beginning with procedures to ablate nerves to the heart in the early part of this century. The evolution of surgical techniques to primary coronary artery bypass grafting is illustrated. Included are subtotal thyroidectomy, pedicle grafting of muscle, omentum, lung, stomach, and jejunum to the pericardium and heart, cardiopericardiopexy, ligation of the great cardiac vein, grafting from aorta to coronary sinus, implantation of arteries into the myocardium, coronary artery bypass grafting, and percutaneous transluminal coronary angioplasty.

Cardiac valve replacement in children: comparison of tissue with mechanical prostheses.

Replacement of cardiac valves in children has been associated with high rates of mortality and morbidity in the past. We have compared 24 children from 2 to 18 years of age who have received mechanical valves with 24 children who have received porcine valves. The groups were similar except that (1) there were more mitral operations in the mechanical valve group and more aortic operations in the porcine valve group; (2) more porcine than mechanical valves were implanted in recent years; and (3) the porcine valve group comprised more young patients under 8 years and required more complex operations. Early and late mortality rates were higher in the mechanical than in the porcine valve group. Major late complications were seen in 50 percent of the mechanical valve group and 13 percent of the porcine group. Implantation of an adult-sized aortic valve was made possible in all patients by the use of aortic augmentation annuloplasty. Higher operative mortality rates in the mechanical valve group may have been related more to technique of myocardial preservation during operation than to type of valve. Although differing rates of late morbidity and mortality may also have been related to myocardial preservation and other technical factors, the type of valve used seemed to be an important determinant of the better results in the porcine group. Despite unknown durability of the porcine valve, our data suggest that the safest prosthetic valve to use in children at this time is the glutaraldehyde-fixed porcine prosthesis.

Atrial myxoma. Clinical manifestations and surgical treatment.

Four patients with atrial myxoma underwent successful surgical excision with the aid of cardiopulmonary bypass at the Medical University of South Carolina. This report describes their clinical manifestations and treatment with special emphasis on advances in surgical technique. This report also emphasizes the malignant potential of this tumor and reviews the recent literature.

Management of spontaneous pneumothorax.

Recurrence is the most common complication of spontaneous pneumothorax. Open thoracotomy with resection of obliteration of blebs and parietal pleurectomy provides the best protection against recurrence. Twenty-seven consecutive patients underwent open thoracotomy for recurrent pneumothorax with no mortality and minimum morbidity and have remained free from recurrence. We believe that thoracotomy should be more widely used in the treatment of what is called spontaneous pneumothorax, since this treatment may remove the real cause of the disease.