Extracorporeal circulation

This electrolyte plays a vital role in the acid-base balance of the body. Bicarbonate may be given IV as sodium bicarbonate (NaHC03) in the treatment of metabolic acidosis, a state of imbalance that may be seen in diseases or situations such as severe shock, diabetic acidosis, severe diarrhea, extracorporeal circulation of blood, severe renal disease, and cardiac arrest. Oral sodium bicarbonate is used as a gastric and urinary alkalinizer. It may be used as a single drug or may be found as one of the ingredients in some antacid preparations. It is also useful in treating severe diarrhea accompanied by bicarbonate loss. 

Extracorporeal circulation Extracorporeal membrane oxygenation Fat embolism Heat stroke... 

Bartlett RH, Roloff DW, Cornell RG, et al. Extracorporeal circulation in neonatal respiratory failure a prospective randomised trial. Paediatrics 1985 76 479-87. 

Metabolic acidosis In severe renal disease uncontrolled diabetes circulatory insufficiency due to shock, anoxia, or severe dehydration extracorporeal circulation of blood cardiac arrest and severe primary lactic acidosis where a rapid increase in plasma total CO2 content is crucial. Treat metabolic acidosis in addition to measures designed to control the cause of the acidosis. Because an appreciable time interval may elapse before all ancillary effects occur, bicarbonate therapy is indicated to minimize risks inherent to acidosis itself. 

Cardiopulmonary bypass, with extracorporeal circulation during cardiac artery bypass graft or heart valve replacement surgery, causes transient hemostatic defects in blood cells and perioperative bleeding. The protease inhibitor aprotinin (Trasylol) inhibits kalhkrein (coagulation phase) and plasmin (hbrinolysis) and protects platelets from mechanical injury. The overall effect after infusion is a decrease in bleeding. 

Adrenaline is used in cardiac resuscitation to convert asystole prior to defibrillation. It is also used in acute hypotensive emergencies and low cardiac output states, especially in severe sepsis or following extracorporeal circulation in cardiac surgery. In anaphylactic shock the combination of powerful a (vasoconstriction) and 32 (bronchodilatation) effects may be life-saving (Appendix AAGBI protocol). Adrenaline is also used to relieve bronchoconstriction in bronchial asthma and status asthmaticus. Dose... 

Isoprenaline occasionally has a place in the management of cardiac conditions in which bradycardia is a feature, e.g. low cardiac output associated with slow heart rate after extracorporeal circulation in patients with excessive p-blocking therapy. It may also be used in the treatment of overdose with (3-adrenoceptor antagonists and for refractory bradyarrhythmias prior to cardiac pacing. Isoprenaline is used in the treatment of bronchial asthma on account of its 32 effects. 

First- and second-trimester abortion Cervical reopening Induction of labor Augmentation of labor Postpartum hemorrhage Ectopic pregnancy Lactation suppression In gastrointestinal disease Peptic ulceration Liver transplantation Chemotherapy-induced mucosal lesions In cardiovascular disease Congenital cardiac malformations Raynaud s syndrome Chronic obstructive pulmonary disease Adult respiratory distress syndrome Pulmonary hypertension Arterial occlusive disease Extracorporeal circulation In urology Erectile dysfunction... 

Prostacyclin infusion (using PGI2 or its synthetic analogue, iloprost) has been used during extracorporeal circulation to prevent blood clotting in the dialyser coil (39). The risk of severe hypotension can be avoided by carefully controlling the infusion rate. 

A 13-year-old boy underwent a 17-hour craniotomy in an attempt to resect an arteriovenous malformation with propofol-based anesthesia. He developed frank propofol infusion syndrome after 74 hours of postoperative propofol sedation in the neurosurgical ICU (used to manage intracranial hypertension). Echocardiography showed severe biventricular dysfunction despite extraordinary pharmacological support. Extracorporeal circulation with membrane oxygenation (ECMO) was instituted at the bedside via cannulation of the left femoral vessels. Hemofiltration... 

PGI2 epoprostenol (inhibits platelet aggregation, used for extracorporeal circulation and primary pulmonary hypertension). 

C2. Chiu, C. J., Blundell, P. E., Scott, H. J., and Gurd, F. N., The intestinal lesions and circulating lysosomal enz3anes in extracorporeal circulation. A clinical and experimental study. J. Thorac. Cardiovasc. Surg. 61, 141-148 (1971). 

Musch G, Verweij M, Bombino M, Banfi G, FumagaUi R, and Pesenti A. Small pore size microporous membrane oxygenator reduces plasma leakage during prolonged extracorporeal circulation A case report. Int. J. Artif. Organs 1996 19(3) 177-180. 

Neya, K. Lee, R. Vlahakes, G.J. Hemoglobin based oxygen carrying solution stability in extracorporeal circulation an in vitro evaluation and impUcations for chnical use. ASAIO J. 1998, 44, 166-170. 

In cardiovascular disease Congenital cardiac malformations Raynaud s syndrome Chronic obstructive pulmonary disease Adult respiratory distress syndrome Pulmonary hypertension Arterial occlusive disease Extracorporeal circulation... 

Annual Book of ASTM Standards (2001) Section 13, Medical Devices and Services. West Conshohocken, PA ASTM. Janvier GC, Baquey C, Roth N, et al. (1996) Extracorporeal circulation, hemocompatibility and biomaterials. Annals of Thoracic Surgery 62 1926-1934. 

Heparin is used as an anticoagulant for prophylaxis and treatment of various thromboembolic disease processes. It is used to maintain relatively anticoagulated states in patients on extracorporeal circulation or hemodialysis and to help maintain patency of indwelling vascular catheters. 

Synthetic membranes are being used increasingly in medicine to process blood for a variety of therapeutic purposes. Such procedures are characterized by extracorporeal circulation and mass transfer across a synthetic membrane in direct contact with blood. The most common of these procedures is hemodialysis, which is used for the treatment of acute or chronic renal failure and drug detoxification (J ). Estimates Indicate... 

In addition to causing their pulmonary sequestration, C5a can Induce release of oxygen radicals from neutrophils (45). Further, both C3a and C5a stimulate mast cells to release histamine. These substances can cause injury to the pulmonary endothelium. Increased vascular permeability and smooth muscle contraction. Such processes have been assoeiated with the severe anaphylactoid reactions reported to occur on rare occasions with the clinical use of membrane devices (46). A connection between complement activation and such reactions has been suggested but not proven. In addition, the sequelae of complement activation may produce the hypoxemia observed during hemodialysis (4 ) and the pulmonary hypertension described in an animal model of extracorporeal circulation (48). 

Heparin monitoring (poor), but widely used during surgery involving extracorporeal circulation... 

Monitoring standard heparin and low mol wt heparins. Routine heparin monitoring is commonly done using the aPTT, but the aPTT is insensitive to the new low mol wt heparins. Common OR procedure in surgeries employing extracorporeal circulation... 

Experimentally and clinically, hyperbaric oxygenation has been used in conjunction with hypothermia and extracorporeal circulation for numerous successful corrective and palliative cardiovascular procedures (B4, B25, B29, M14, R2, W4). Meijne (M12) emphasizes the need to separate the value of OHP during the actual period of cardiac arrest and the value of OHP after the arrest period during lowered cardiac output. Because of the moderate oxygen stores of the body at 3 ata and the requirement for the large oxygen tension gradients between the capillaries and the mitochondria, he recommends that OHP be used mainly in conditions where at least some circulation is present. ... 

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