Hemodynamic Defects Research Articles

Critical Care Medicine Manual

The book is a compilation of talks covering most aspects of critical care medicine, which were presented at the annual symposia sponsored by the Postgraduate Division of the Southern California School of Medicine. The list of authors constitutes the blue book of critical care medicine: William Ganz, R. M. Hardaway, Henning Pontoppidan, Peter Safar, William C. Shoemaker, and H. T. C. Swan. For many of the contributors, this is a presentation of frontier work. Several topics have received excellent treatment, particularly Treatment of Shock and Trauma States, Brain Monitoring and Homeostasis, and Hemodynamic Defects Including Shock. Coverage is not uniform; most pertinent problems are treated in depth, but many questions are left unanswered. Nevertheless, the editors have managed the difficult task of subdividing the book and have provided well-organized titles and subtitles. The result is a book that is well balanced typographically, but it is obvious that many of the

Late results after repair of tetralogy of Fallot

Three hundred eleven patients up to 17 years of age underwent repair of tetralogy of Fallot from 1964 through 1970. Age of early death group versus early survivor group was 6.1 versus 7.5 years (p = 0.03), and the right ventricular–to–left ventricular (RVILV) pressure ratio was higher for the early death group—0.663 versus 0.569 (p < 0.01). Use of an outflow tract patch was associated with only a minimally higher early mortality rate (p = 0.07). Of early survivors, late results were ideal in 80 per cent, fair in 10 per cent, and poor in 3 per cent; the late mortality rate was 4 per cent. Five per cent had residual hemodynamic defects. The mean cardiothoracic (CT) ratio was 0.485 for the group with ideal results and 0.567 for those with poor results. The RV/LV pressure ratio after repair was considerably higher in the group with poor results (0.74 versus 0.56). These studies give support for (1) the need to achieve as complete a repair of pulmonary stenosis as possible, even if pulmonary insufficiency results and an outflow tract patch is required, and (2) continued avoidance of the insertion of a substitute pulmonary valve during repair of tetralogy in the typical patient until the long-term fate of such valves is known.

The Axillo-axillary Bypass Graft

The recent utilization of the axillo-axillary bypass graft for revascularization of proximal subclavian or innominate artery occlusions has proved to be a successful operation, technically simple with a low operative morbidity. We have reviewed the reported experience to date and have added our experience of nine additional cases. The procedure has produced excellent results in all patients, with no evidence of postoperative "steal" from the donor limb. Preoperative hemodynamic defects were corrected. Our experience has led us to the conclusion that this simpler and safer extrathoracic approach should be considered as the procedure of choice when arterial lesions allow for its selection and use.

Intensive Study and Treatment of Shock in Man

The most important treatment of noncardiac shock is fluid volume administration given, if necessary, to the point of an elevated central venous or pulmonary artery pressure. Adequate volume is more important than the type of fluid administered. Blood is given only up to a normal red blood cell mass. If these measures are not adequate, a vasodilator may produce dramatic improvement. No detrimental effect was ever seen. Vasopressors may produce detrimental effects in shock. An adequate arterial oxygen pressure (Po₂) is essential and often requires tracheotomy or tracheal intubation with oxygen and a respirator to obtain. It has been possible to correct all hemodynamic defects in shock. Patients who have died have done so as a result of pulmonary lesions. Disseminated intravascular coagulation is usual in severe shock. Its onset is heralded by a clotting defect frequently only noted by laboratory test. In some cases it causes important clinical hemorrhage and requires treatment. It may play an important part in the development of lethal shock including acute pulmonary failure.

The use of valve prostheses in childhood

Summary The use of valve prostheses for the treatment of congenital valve deformities in children has been discouraging because of the need to replace these prostheses later in life due to their small flow area as well as the unsettled question of the need for prolonged anticoagulant therapy. Two cases of aortic valve replacement in children with prostheses of our design, incorporating a full-orifice flow characteristic, are presented. They demonstrate the feasibility of providing children with a prosthetic valve adequate to sustain adult activity and of such a design that anticoagulant therapy is less likely to be indicated. The availability of these new prostheses allows these children with irreparable congenital valve deformities an opportunity to have total repair of their hemodynamic defects.