Keiji Kumon

Assessment of coronary blood flow by transesophageal two-dimensional pulsed Doppler echocardiography

Abstract Recent advances in Doppler echocardiographic techniques enable us to estimate coronary flow dynamics in patients. 1–5 These methods, however, require invasive procedures, and repeated examinations in the same patient are undesirable. Although noninvasive detection of coronary flow with conventional Doppler technique from a transthoracic approach has been performed, 6,7 technical problems—effects of cardiac motion and difficulty in differentiating coronary blood flow from other intracardiac flow—remain. Transesophageal pulsed Doppler echocardiography, 8 originally reported to estimate mitral regurgitation, 9 may also be available in detecting coronary flow when combined with 2-dimensional echocardiography. In the present study, we attempted to detect coronary flow by the transesophageal Doppler technique.

Anticoagulation with a synthetic thrombin inhibitor after cardiovascular surgery and for treatment of disseminated intravascular coagulation.

A synthetic thrombin inhibitor, MD-805, was used to anticoagulate 15 patients after cardiovascular surgery (CVS). A mean infusion rate of 0.71 ± 0.1 (SD) μg/kg.min maintained an activated coagulation time of about 150 sec in all patients, and significantly prolonged both activated partial thromboplastin time and prothrombin time. MD-805 was also administered to ten patients with disseminated intravascular coagulation (DIC), eight of whom had not responded to either heparin or gabexate mesilate (FOY), and eight of whom had circulating antithrombin III levels below 20 mg/dl. MD-805 therapy was successful in nine DIC patients. These results recommend MD-805 anticoagulant therapy after CVS and for treatment of DIC, especially when circulating levels of antithrombin III are low.

Continuous measurement of coronary sinus oxygen saturation after cardiac surgery.

To estimate the balance of myocardial oxygen supply and demand after cardiac surgery, we used fiberoptic reflection oximetry to measure continuously the coronary sinus oxygen saturation (Scso2) in six patients. Scso2 decreased with massive bleeding, atrial fibrillation, after DC countershock, and continuous iv infusion of hydralazine, phentolamine, and dibutyryl cyclic-AMP. Scso2 increased with iv infusion of nicardipine or nitroglycerin, suggesting an improved oxygen metabolism in the myocardium. Continuous Scso2 measurement provides such on-line information on myocardial oxygenation in postoperative patients.

Respiratory care of pediatric patients requiring prolonged intubation after cardiac surgery.

Pediatric patients requiring intubation more than 4 days after cardiac surgery can experience many respiratory and other problems. We found that 48 of 264 pediatric patients could not be extubated within 4 days after open-heart surgery because Pao2 was less than 75 torr and Paco2 was over 45 torr on an inspired oxygen fraction of 0.4. Most of the 48 patients were under 12 months old, had pulmonary hypertension and/or complex cardiac anomalies, and were not hemodynamically stable and/or fully conscious. The intensity of long-term intubation was attributed to cardiovascular or respiratory complications and multiple organ failure.At the time of extubation, water infusion was maintained below 80 ml/kgday and positive water balance below 15 ml/kgday. Calories and amino acid were maintained over 70 kcal/kgday and 1.5 g/kgday, respectively.

Evaluation of rapid drying hand disinfectant preparations in the intensive care unit.

MK412A (0.2% chlorhexidine in 70% ethanol) and MK412B (0.2% benzalkonium chloride in 70% ethanol), which are rapid drying and rubbing antiseptic preparations, have been evaluated for hand sterilization over a month by ICU nurses. They have been shown to have effective skin decontaminant efficacy under practical conditions in a busy ICU. There were no adverse reactions except for two cases of mild erythema in the MK412A treatment group. In a comparative in vitro study with Pseudomonas cepacia, 0.2% chlorhexidine solution alone and 0.2% benzalkonium chloride solution alone were less bactericidal than MK412A and MK412B.