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R K Grooters

Publications and source records attributed to R K Grooters.

13 recordsLinked to original sources
PubMed1995

Flow study of surgical coronary artery fistula as an alternative to sequential bypass.

Surgical coronary artery fistula, in which the last anastomosis is created to a low-pressure cardiac chamber, was recently introduced as an alternative method to improve graft flow and patency in a sequential graft when coronary arteries are small or diffusely diseased. To assess graft flow, effect on haemodynamics, flow distribution and to determine proper size of the distal anastomosis, a saphenous vein was sequentially anastomosed from the ascending aorta to the left anterior descending artery and then to the left atrium in eight mongrel dogs. Graft flow was measured before and after opening the fistula to the left atrium between the ascending aorta and left anterior descending artery (flow A) and between the left anterior descending artery and left atrium (flow B). Left atrium pressure and systolic left ventricular pressure (mmHg) were recorded. The diameter of the distal anastomosis was regulated with a bulldog clamp. When distal anastomosis was at 2.5-3 mm mean(s.d.) flow A increased from 64.5(19.5) to 134.7(28.5) ml/min (P < 0.01) without significant left atrial pressure or left ventricular pressure change. With a distal anastomosis of 4 mm or more, flow A increased from 69.8(19.9) to 396.1(62.2) ml/min (P < 0.001). Left atrial pressure increased from 5.6(1.0) to 6.1(0.9) mmHg (P < 0.05) without a change in left ventricular pressure. In both sizes of distal anastomosis, flow to the left anterior descending artery did not change either before or after the shunt (flow B) was opened. Neither volume loading, rapid atrial pacing, neosynephrine or epinephrine infusions caused deleterious haemodynamic effects with the shunt open.(ABSTRACT TRUNCATED AT 250 WORDS)

Anastomosis, Surgical↗
PubMed1991

Clinical alternative bypass conduits and methods for surgical coronary revascularization.

Poor quality or inadequate length of venous and mammary conduits, or both, a severely calcified or atherosclerotic aorta, or diffuse coronary atherosclerosis are situations cardiovascular surgeons will be facing with increasing frequency. These conditions are more common to the increasing number of patients requiring reoperation for advancing disease and to the growing number of older patients requiring operation. Decisions will be made preoperatively or intraoperatively about the technique to be used. Extensive use of the internal mammary arterial graft, such as bilateral internal mammary artery bypass, sequential use of the mammary artery and use of a free internal mammary artery graft, are excellent choices. These methods can overcome some of the difficult situations of the severely calcified atherosclerotic aorta or the absence of adequate venous conduits. Coronary arterial bypass using the inverted internal mammary conduit has too low a flow to be considered. Composite conduits will help gain the length needed to solve both the inadequate length problem and the severely diseased aorta. Little clinical experience is reported to date. These methods should only be used when nothing else is available. The innominate to coronary arterial bypass and the left subclavian to coronary arterial bypass can help solve the problem of the severely atherosclerotic aorta. The coronary to coronary arterial bypass has been used to solve both the severely diseased aorta and the short conduit situation. These methods, while ingenious, are supported only by occasional isolated clinical experiences. A large number of researchers have done extensive work on the selective retrograde coronary venous bypass grafting, but the last published article of any clinical importance dates back to 1979 and this suggests that other alternatives may be better. This technique should be used as a last resort. The surgical arteriovenous fistula has been clinically applied during the coronary artery bypass procedure. The nonconduit revascularization technique of coronary artery endarterectomy is needed in the armamentarium of the surgeon. This technique is not ideal but presently has better results than intraoperative transluminal coronary angioplasty and far better results than laser angioplasty. These methods may be useful to solve the diffuse coronary arterial problem, but sequential grafting techniques should be considered first.

Angioplasty, Balloon, Coronary↗
PubMed1991

Discriminate use of electrocautery on the median sternotomy incision. A 0.16% wound infection rate.

Between June 1978 and June 1989, superficial or deep mediastinitis (or both) developed in only five (0.16%) of 3118 consecutive patients. All patients studied underwent cardiac procedures through a median sternotomy and survived more than 7 postoperative days. The surgical team disciplined itself to divide presternal soft tissues with a scalpel and used electrocautery for pinpoint hemostasis only. This 0.16% infection rate was statistically significantly lower than those in 28 previously published studies (Pearson's chi 2 test, p less than 0.05). Twenty-four predisposing factors were evaluated by Fisher's exact test. Among these only an operating time longer than 3 hours is related to sternotomy infections (p = 0.0208), and this effect was not a strong one. Statistical evidence strongly suggests that discriminate use of electrocautery is a major reason for the lowest median sternotomy infection rate reported to date.

Adult↗
PubMed1990

Postoperative mediastinitis: a comparison of two electrocautery techniques on presternal soft tissues.

Postoperative mediastinitis remains a serious surgical problem, complicating 0.4% to 5% of all cases. In an experiment designed to address this problem, 36 mongrel dogs underwent a median sternotomy incision. In group I (n = 18) all layers to the sternum were opened by a scalpel, and electrocautery was used only for pinpoint hemostasis. In group II (n = 18) the skin was opened by a scalpel and the remaining layers to the sternum were opened by electrocautery. Total kilojoules of electrical energy delivered to the tissues was 9.4 +/- 5.7 for group I and 44.1 +/- 7.0 for group II (p less than 0.001). Each group was randomly divided into three subgroups (n = 6): Ia and IIa were noninoculated controls; Ib and IIb were inoculated just before skin closure; Ic and IIc were inoculated and given one preoperative dose of cefonicid. The inoculum contained Staphylococcus intermedius in a 0.5 ml suspension of 10(8) organisms. Each animal was observed and the wounds were scored daily until death or until all survivors were put to death on the eighth postoperative day. Pleural fluid was cultured at autopsy. Ten dogs died of mediastinitis (four in IIa and six in IIb), but none from group I (p less than 0.01). Positive cultures from pleural fluid in matching subgroups (n = 6) occurred as follows: one in Ia and five in IIa (p less than 0.05); one in Ib and six in IIb (p less than 0.01); zero in Ic and two in IIc. We conclude that pinpoint hemostasis on the soft tissues of the sternotomy incision significantly reduces the severity and frequency of penetrating mediastinitis.

Animals↗
PubMed1989

Carotid and aortic arch endarterectomy using hypothermic arrest with coronary bypass.

A 67-year-old man with symptomatic bilateral carotid artery obstructions and a large, friable atheromatous plaque of the transverse aortic arch required coronary artery bypass grafting for severe triple-vessel disease. An endarterectomy of the transverse arch and a left carotid endarterectomy were performed using deep hypothermic circulatory arrest concomitant with quadruple coronary artery bypass grafting. Recovery was uneventful. Hypothermic circulatory arrest provides adequate protection for this combined procedure and may eliminate cerebral embolization.

Aged↗
PubMed1989

Surgical closure of the patent ductus arteriosus in the neonatal intensive care unit.

Efficacy of surgical closure versus indomethacin for treatment of patent ductus arteriosus in symptomatic neonates is an ongoing controversy. In recent years, surgical closure has been performed in the neonatal intensive care unit rather than the operating room in some centers, creating further controversy. In a retrospective study of the charts of 115 sequential patent ductus arteriosus surgical closures performed in the neonatal intensive care unit in premature infants, we found no surgical morbidity or mortality. Ninety-nine of these infants of less than 33 weeks gestational age were evaluated for various factors that might influence outcome. All were operated on within 72 hours of diagnosis, with an extra-pleural approach and metal clips used for closure of the ductus. All infants were extubated at an average of 33 weeks in each age group studied unless they had underlying severe bronchopulmonary dysplasia. We conclude that surgical closure of the symptomatic patent ductus arteriosus in neonates is safe and 100% effective, with none of the reported complications of indomethacin therapy, and should be the treatment of choice in neonates aged less than 33 weeks (gestational age) at birth with symptomatic patent ductus arteriosus. Closure performed in the neonatal intensive care unit eliminates transport risks and is ultimately safer and easier than transport to an operating room.

Ductus Arteriosus, Patent↗
PubMed1988

Coronary-coronary bypass using internal mammary artery.

A free right internal mammary artery was used to bypass the right coronary artery in a patient with no available saphenous vein. The proximal end of the right internal mammary artery was anastomosed to the proximal right coronary artery, and the distal end of the free graft was anastomosed to the posterior descending coronary artery. Coronary-coronary bypass using a free internal mammary artery is an attractive approach to bypassing very distal vessels when other conventional grafting techniques are not possible.

Coronary Artery Bypass↗
PubMed1987

Coronary-coronary artery bypass: an alternative.

Occasionally, a patient with calcification of the ascending aorta will be unsuitable for conventional saphenous vein aortocoronary bypass. Similarly, when a patient is seen with saphenous vein (or internal mammary artery) of inadequate diameter or quality, another method of revascularization must be selected. Two cases of coronary-coronary artery bypass are illustrative of one solution to these difficult and increasingly common problems.

Aged↗