Surgical management of catheter tip thrombus: surgical therapy for right atrial thrombus and fungal endocarditis (Candida tropicalis) complicating paediatric sickle-cell disease.

The use of indwelling central catheters for long-term administration of hyperalimentation, chemotherapy or other intravenous therapies is increasing. This unusual presentation of a catheter-induced right atrial thrombus was complicated by fungal infection. We present a case of a paediatric sickle-cell patient who underwent surgical removal of a right atrial thrombus secondary to fungal (Candida tropicalis) endocarditis from an indwelling catheter. Successful thrombus removal utilizing cardiopulmonary bypass and subsequent discharge underscores the importance of surgical therapy in treating this important complication.

Safe use of heparin-coated bypass circuits incorporating a pump-oxygenator.

Durable, covalently bonded, heparin-coated cardiopulmonary bypass (CPB) circuits with oxygenators have been developed. Proposed advantages of heparin-coated CPB circuits include improved biocompatibility and thromboresistance. The purpose of this study was to evaluate our experience with heparin-coated CPB circuits in 20 patients. Heparin was given to maintain an activated clotting time equal to or greater than 200 seconds, while flow rates were kept equal to or greater than 2 L/min. Indications for use of this circuit included recent stroke, posttraumatic injuries, recent gastrointestinal bleeding, protamine allergies, combined cardiac and noncardiac procedures, and ventricular assist. Mean heparin dosage was 0.50 +/- 0.18 mg/kg and protamine dosage was 57.14 +/- 39.36 mg. Postoperative blood loss and transfusion requirements were minimal. Postoperative complement levels of C3a and C5a were normal, suggesting excellent biocompatibility. There were no deaths or perioperative complications. Heparin-coated CPB circuits using a pump oxygenator can be used safely with low-dose heparin administration in select patients requiring CPB.

Experimental amitriptyline poisoning: treatment of severe cardiovascular toxicity with cardiopulmonary bypass.

STUDY OBJECTIVE: To compare cardiopulmonary bypass (CPB) with more conventional therapy in the treatment of severe amitriptyline poisoning. DESIGN: Prospective, randomized, controlled, laboratory investigation. INTERVENTIONS: Profound cardiovascular toxicity was induced in 20 anesthetized Yorkshire swine (72 +/- 8.3 kg) by amitriptyline infusion at 0.5 mg/kg/min. Ventilation was adjusted to keep arterial pH at 7.50 +/- 0.05 and the PCO2 at 35 mm Hg. The swine were randomized in a 1:1 ratio to one of two groups, CPB or control. Both groups received amitriptyline infusion until they experienced near-lethal toxicity, defined as a systolic blood pressure below 30 mm Hg for one minute. The control group was then given supportive treatment, including IV fluids, sodium bicarbonate, vasopressors, and standard pharmacologic (advanced cardiac life support) interventions. Control animals failing to respond to supportive measures after five minutes were given open-chest cardiac massage for 30 minutes or until the return of spontaneous circulation. The CPB group received only mechanical support by CPB for 90 to 120 minutes. No sodium bicarbonate, antiarrhythmics, or cardiotonic agents were provided to the CPB group during this resuscitation. RESULTS: All 20 animals experienced cardiac conduction delays, dysrhythmias, and progressive hypotension within 30 minutes of receiving IV amitriptyline at 0.5 mg/kg/min. The ten swine receiving CPB as treatment for cardiovascular toxicity were able to completely correct the dysrhythmias, cardiac conduction abnormalities, and hypotension produced by the amitriptyline; however, only one of ten control animals could be resuscitated (P = .0001). Nine of ten swine treated with CPB were easily weaned off bypass without any pharmacologic intervention; however, one required norepinephrine to be weaned. All 11 resuscitated swine were able to be salvaged. CONCLUSION: CPB improved survival in our swine model of severe amitriptyline poisoning.

Use of heparin-coated cardiopulmonary bypass.

A 49-year-old man with unstable angina and a history of severe anaphylaxis to seafood and intravenous iodine needed myocardial revascularization. Because of concern of an intraoperative protamine reaction, preoperative treatment was instituted with steroids and with H1 and H2 blockers. Revascularization was accomplished using a heparin-coated cardiopulmonary bypass circuit. Complement activation and postoperative bleeding were minimal. Heparin-coated cardiopulmonary bypass is a safe, effective technique of bypass in select patients.