Leukocyte filtration and miniature perfusion during arrested heart CABG on a Jehovah's Witness patient.

Bloodless surgery and a reduction in the use of allogeneic blood products has long been the standard of care in medicine. Many individuals in our communities have demanded this form of surgical treatment for personal and religious reasons. On 6 December 2002, a 72-year-old male patient was admitted to our institution as a critical air flight transfer. The patient's height was 190.5 cm and weight was 59.3 kg (body surface area 1.83 m2). His preliminary diagnosis was chest pain with myocardial infarction as evidenced by elevated blood cardiac isoenzymes. His principle diagnosis was subendocardial infarction with paroxysmal ventricular tachycardia. Cardiac catheterization was performed and demonstrated severe triple vessel disease with an ejection fraction of 30%. He was evaluated and accepted as a candidate for coronary artery bypass grafting. Multidisciplinary consultation concluded that a safe and effective method of perioperative treatment would involve the use of arrested heart support with cold blood cardioplegia using a low prime miniature perfusion circuit as no blood products would be considered for use. Additionally, the combined modalities of perfusion interventions to minimize hemodilution consisted of intraoperative autologous blood collection totaling 500 mL and rapid autologous priming of the miniature perfusion circuit. The miniature perfusion system was a low prime Cardiovention (Santa Clara, CA) CORx device which includes a hollow-fiber oxygenator and integral centrifugal pump with a surface area of 1.2 m2. This system also incorporates an air sensing solenoid which triggers rapid air evacuation in a bolus range of 1 mL or greater. Kinetic venous drainage is another feature of this device as the centrifugal pump is integrated into the oxygenator. We believed that a miniature extracorporeal circuit would enhance the desired clinical outcome as opposed to the risk of: (1) off-pump coronary artery bypass (OPCAB) approach and the concern of emergent transition to an on-pump procedure and (2) use of larger surface area with conventional systems that impose a greater hemodilutional effect. Leukocyte filtration was employed as the patient had a significant past medical history of chronic obstructive pulmonary disease. We herein report our clinical experience with this method of treatment on a patient who refused the use of blood products in his surgical treatment. It is our belief that the multiple modalities utilized in combination during this procedure resulted in positive clinical outcomes as demonstrated by an intubation time of 8 hours 35 min with a discharge on the fifth postoperative day.

Prospective analysis of endoscopic vein harvesting.

BACKGROUND: Utilization of bridging vein harvesting (BVH) of saphenous vein grafts (SVG) for coronary artery bypass grafting (CABG) results in large wounds with great potential for pain and infection. Endoscopic vein harvesting (EVH) may significantly reduce the morbidity associated with SVG harvesting. METHODS: A prospective database of 200 matched patients receiving EVH and BVH was compared. The patients all underwent CABG done over a period of 4 months (April to August 2000). Patients were excluded if they had prior vein harvesting. RESULTS: The EVH and BVH group included 100 patients each with similar demographics. The patients in the EVH group had significantly fewer wound complications, mean days to ambulation, and total length of stay (P <0.05). There was no difference in harvest time or vein injuries. CONCLUSION: Endoscopic vein harvesting results in significantly fewer wound complications, decrease in days to ambulation, and the total length of stay. EVH is superior to BVH in patients undergoing CABG.

Inhibition of the creatine kinase reaction decreases the contractile reserve of isolated rat hearts.

To define the relation between phosphoryl transfer via creatine kinase (CK) and the ability of the intact beating heart to do work, we chemically inhibited CK activity and then measured cardiac performance under physiological and acute stress conditions. Isolated perfused rat hearts were exposed to iodoacetamide (IA) and subjected to one of three cardiac stresses: hypercalcemic (Ca2+ = 3 mM) buffer perfusion (n = 7), norepinephrine (2 mumol/min) infusion (n = 6), or hypoxic buffer perfusion (n = 5). IA decreased CK activity to near zero, measured in intact hearts by 31P magnetization transfer, and to 2% of control CK activity, measured in myocardial homogenates. The CK isoenzyme profile was unchanged, suggesting nonselective IA inhibition of all isoenzymes. Mitochondria isolated from IA-treated hearts had normal ADP:O ratios, state 3 respiratory rates, and unchanged acceptor and respiratory control ratios. Neither actomyosin adenosinetriphosphatase nor adenylate kinase activities were changed. After IA exposure, end-diastolic pressure, left ventricular developed pressure, and heart rate were unchanged for at least 30 min at physiological perfusion pressures, but large changes were observed during stress conditions. The increase in left ventricular developed pressure induced by hypercalcemic perfusion and by norepinephrine infusion decreased by 39 and 54%, respectively. During hypoxia, the rate of phosphocreatine depletion was decreased by 57%, left ventricular developed pressure declined, and end-diastolic pressure increased faster than in controls. These results show that inhibition of CK to < 2% of control activity by IA reduced contractile reserve by approximately 50%. We conclude that CK activity is essential for the expression of the full dynamic range of myocardial performance.

Injuries resulting from motorized personal watercraft.

To determine if there is a widespread problem with personal watercraft (jet ski) injuries throughout the United States, we reviewed the hospital records of patients who were treated at this institution for injuries incurred while they were operating a motorized personal watercraft or jet ski. All of the patients were under the age of 19 and suffered severe fractures or lacerations. To assess the extent of the problem with these injuries regionally, we collected data from 8 midwestern states for 1989. Sixty-four personal watercraft accidents involving 90 victims were reported in the survey. Fifty-three of 90 patients sustained fractures, lacerations, or head injuries. Seventy-nine of 90 were under age 25, and 24 patients were under 16 years of age. The need for supervision and the potential for serious injury while operating personal watercraft is supported by these findings.

Helicopter transport of trauma victims: does a physician make a difference?

We studied the impact of physician presence on helicopter transportation of trauma victims during two periods; when physicians were part of the flight team and when they were not. Our data failed to demonstrate that physician participation in flights had an impact on patient outcome. The groups were comparable in average distance traveled, initial Trauma Scores, number of organ systems injured, and the final Injury Severity Scores. Each group showed an improved survival over that predicted by comparison with the Multiple Trauma Outcome Study cohort. No difference was found in the number of procedures performed at the scene, en route, or on arrival at the hospital. Untreated injuries were slightly higher in the physician-present group. It appears that experienced nurses and paramedics, operating with well-established protocols, can provide aggressive care that yields equal outcome results compared with those of a flight team that includes a physician.

Velocity of the creatine kinase reaction decreases in postischemic myocardium: a 31P-NMR magnetization transfer study of the isolated ferret heart.

Recovery of postischemic function may be limited by energy synthesis by mitochondria, energy transfer via the creatine kinase reaction, or energy utilization at myofibrils. To identify the limiting step, we defined the relations among oxygen consumption, creatine kinase reaction velocity and cardiac performance in myocardium reperfused following mild, moderate, and severe ischemia. Isolated isovolumic ferret hearts were perfused with Krebs-Henseleit buffer at 37 degrees C. After 30 minutes of control, hearts were made ischemic for 20, 40, or 60 minutes and reperfused for 40 minutes. During preischemia, cardiac performance (estimated as the rate-pressure product), was 14.8 x 10(3) mm Hg/min, oxygen consumption was 16.7 mumol/min/g dry weight, and creatine kinase reaction velocity measured by 31P-nuclear magnetic resonance saturation transfer was 12.7 mM/sec. For hearts reperfused after 20, 40, or 60 minutes of ischemia, rate-pressure product was 11.5, 6.5, and 1.1 x 10(3) mm Hg/min; oxygen consumption was 13.5, 14.2, and 6.9 mumol/min/g dry weight; and creatine kinase reaction velocity was 9.6, 5.0, and 2.0 mM/sec, respectively. Thus, with increasing severity of insult, creatine kinase reaction velocity decreased monotonically with performance (r = 0.99). Changes in creatine kinase reaction velocity were predicted from the creatine kinase rate equation (r = 0.99; predicted vs. measured velocity) and can therefore be explained by changes in substrate concentration. Oxygen consumption did not correlate with performance or creatine kinase velocity, consistent with abnormalities in mitochondrial energy production. In all cases, creatine kinase reaction velocity was an order of magnitude faster than the maximal rate of ATP synthesis estimated by oxygen consumption. We conclude that, in postischemic myocardium, creatine kinase reaction velocity decreases in proportion to performance, but high-energy phosphate transfer does not limit availability of high-energy phosphate for contraction.