Yutaka Ogawa

Results of omental flap transposition for deep sternal wound infection after cardiovascular surgery.

OBJECTIVE Our experience with omental flap transposition in the treatment of deep sternal wound infections is reviewed here with an emphasis on efficacy, risk factors for in-hospital mortality rates, and long-term results. SUMMARY BACKGROUND DATA Even with improvements in muscle and omental flap transposition, the timing of closure and the surgical strategy are controversial. METHODS Forty-four consecutive patients with deep sternal wound infections were treated using the omental flap transposition from 1985 through 1994. The strategies included debridement with delayed omental flap transposition or single-stage management, which consisted of debridement of the sternal wound and omental flap transposition. Methicillin-resistant Staphylococcus aureus was cultured from more than 50% of the wounds. A logistic regression analysis was used to identify the predictors of in-hospital death after omental flap transposition. RESULTS There were seven (16%) in-hospital deaths. Univariate analysis demonstrated that hemodialysis and ventilatory support at the time of omental flap transposition were significantly associated with in-hospital mortality rates (p = 0.0023 and p = 0.0075, respectively). Thirty-seven patients whose wounds healed well were discharged from the hospital. Two patients with cultures positive for methicillin-resistant Staphylococcus aureus had recurrent sternal infections. Patients without positive methicillin-resistant Staphylococcus aureus cultures had good long-term results after reconstructive surgery. CONCLUSIONS Transposition of an omental flap is a reliable option in the treatment of deep sternal wound infections, unless the patients require ventilatory support or hemodialysis at the time of transposition.

Left atrial function after Cox's maze operation concomitant with mitral valve operation

BACKGROUND This study examined whether the atrial fibrillation that commonly occurs in patients with a mitral valve operation could be eliminated by a concomitant maze operation. METHODS Left atrial function after Coxs maze operation performed concomitantly with a mitral valve operation was evaluated in 10 patients ranging in age from 38 to 67 years (mean age, 54 years). Seven patients who had had coronary artery bypass grafting served as the control group. Using transthoracic echocardiography, the ratio between the peak speed of the early filling wave and that of the atrial contraction wave (A/E ratio) and the atrial filling fraction (AFF) were determined from transmitral flow measurements. These two indices have been considered to represent the contribution of left atrial active contraction to ventricular filling. RESULTS The A/E ratio and the AFF were significantly lower in the maze group (0.35 +/- 0.17 versus 0.97 +/- 0.28 [p < 0.01] and 17.6% +/- 8.8% versus 36.8% +/- 6.4% [p < 0.01], respectively). The A/E ratio and the AFF correlated inversely with age (r = -0.72, p < 0.05 and r = 0.76, p < 0.05, respectively) in the maze group. In an angiographic study, the mean left atrial maximal volume index in the maze group was approximately three times larger than that in the control group (117.5 +/- 24.3 mL/m2 versus 35.3 +/- 6.6 mL/m2 [p < 0.01]). The left atrial active emptying volume index was significantly smaller in patients in the maze group (7.2 +/- 2.5 mL/m2 versus 13.1 +/- 4.6 mL/m2 [p < 0.01]). CONCLUSIONS After the maze procedure performed concomitantly with a mitral valve operation in patients with a dilated left atrium, left atrial contraction is detectable but incomplete in the elderly.

Clinical application of total body retrograde perfusion to operation for aortic dissection

The use of profound hypothermia and total circulatory arrest in the surgical treatment of aortic dissection has previously been reported. However, the safe period of prolonged circulatory arrest with hypothermia remains controversial. We have developed a technique of hypothermic total body retrograde perfusion to achieve systemic organ protection: cerebral protection by continuous retrograde perfusion through the superior vena cava, myocardial protection by coronary sinus infusion, and abdominal visceral organ perfusion by continuous retrograde perfusion through the inferior vena cava. Our technique yields a relatively bloodless operating field and avoids hypoperfusion of vital organs through a false lumen.

Selective jugular cannulation for safer retrograde cerebral perfusion

Hypothermic retrograde cerebral perfusion is a new technique for protecting the brain. Satisfactory cerebral protection should be possible even for periods of retrograde perfusion greater than 60 minutes. However, there are some concerns that functioning venous valves at the jugular-subclavian junction may impede retrograde flow to the brain and consequently cerebral protection may not be adequate. To overcome this obstacle, we have developed an easy and safe technique of selective jugular cannulation through the right atrium using a central venous catheter and a guidewire. We have employed this technique successfully in 15 patients who underwent operation on the aortic arch.

New modification of a mammary artery retractor

A new accessory instrument to the self-retaining internal mammary artery retractor was developed. This instrument presses the chest wall inward, relieves the concavity of the inner surface of the chest wall, and provides good exposure of the internal mammary artery.

Dissolution of pancreatic stones by oral trimethadione in a dog experimental model.

Experiments were conducted to develop a dissolution therapy for human pancreatic calculi in a dog experimental model of pancreatic calculi surgically prepared. On plain x-ray films of the abdomen, pancreatic calculi appeared in 19 of 39 dogs within 12 mo after operation. The antiepileptic agent trimethadione was given orally to 13 dogs at a dose of 1.0-1.5 g daily. Pancreatic calculi disappeared in 13 of 15 observations. The scanning electron microscopy, the elemental analysis, and the powder x-ray diffractometry of pancreatic calculi in this model revealed that the calculi closely resembled human pancreatic calculi, consisting mainly of a calcite of calcium carbonate. There was no histologic finding suggesting drug toxicity in the liver, the kidney, and the blood. Pancreatic calculi in 6 control dogs without the treatment neither disappeared nor diminished spontaneously. The oral treatment with trimethadione may have potential for dissolving human pancreatic calculi.

Resection of aortic aneurysms without aortic clamp technique with the aid of hypothermic total body retrograde perfusion

Aneurysms involving either the aortic arch or the proximal descending thoracic aorta in five patients were resected with the aid of profound hypothermic total body retrograde perfusion. Traditional surgical management of the aortic arch and the descending thoracic aorta necessitates clamping of the aorta. However, this technique may be associated with rupture or atheroembolism. Rupture occurring at the clamping site may be difficult to repair. Atheroembolism to the brain compromises the neurologic system, and multiple organ embolism is associated with disseminated intravascular coagulopathy. Atheroembolism in cardiovascular surgery has become increasingly prevalent. It is necessary to prevent clamp injuries and to preserve the function of the vital organs, such as the brain, heart, and liver, during aortic reconstruction. We applied a total body retrograde perfusion technique to operations for aortic aneurysms. Total body retrograde perfusion consists of cerebral protection by continuous perfusion through the superior vena cava, intermittent retrograde coronary perfusion through the coronary sinus, and continuous abdominal visceral perfusion through the inferior vena cava. It can yield a relatively bloodless operating field without the need for aortic clamping. We believe this new adjunct offers excellent results in the surgical treatment of aneurysms of the aortic arch or adjacent structures.

Early experience of retrograde cerebral perfusion

Since 1990, retrograde cerebral perfusion has been applied in aortic arch surgery in the Nagoya University group to protect the brain. This study reviews the groups early clinical results, and especially of neurological outcome in patients undergoing aortic arch surgery via mid sternotomy by using retrograde cerebral perfusion only via the superior vena cava. Seventy-three cases (47 men, 26 women; mean age 62.3 (range 26-82 years)) participated in the study. True aneurysm was diagnosed in 17 cases and aortic dissection in 56. Emergency operations were performed in 49 cases (67%). The proximal aortic arch was replaced in 38 cases, the total aortic arch in 21, the distal arch in six, and the aortic root in two. Mean (s.d.) retrograde cerebral perfusion duration was 55(23) (range 12-115) min and superior vena cava flow rate 350(143) ml/min. Excluding four cases of early surgical death, a total of 10 patients (14.5%) showed neurological dysfunction. Symptoms were coma in eight cases and motor paralysis in two. Three of these 10 cases were recovered without symptoms and six died. The early mortality rate was 19.2%. Significant differences in retrograde cerebral perfusion duration (49(20) versus 83(18) minutes, P < 0.001), superior vena cava pressure (23.2(7.2) versus 28.2(7.4) mmHg, P = 0.046), and preoperative cardiac arrest P < 0.05) were evident between groups with and without neurological dysfunction. There were no neurological dysfunctions in patients undergoing retrograde cerebral perfusion for < 60 minutes at under 30 mmHg of superior vena cava pressure. In conclusion, retrograde cerebral perfusion may be used to extend the duration of safe cerebral circulatory arrest.

Development of a new data entry system suitable for the Japan Adult Cardiovascular Surgery Database

PurposePatient data related to cardiovascular surgery are usually managed separately by surgeons and clinical engineers in their respective data files. Recently, with our participation in the Japan Adult Cardiovascular Surgery Database (JACVSD), we newly prepared JACVSD-ready cardiovascular surgery data files by combining two data entry systems.MethodsWe constructed a cardiovascular surgery database system using FileMaker Pro and FileMaker Server. When preparing the data files, we attempted to eliminate excessive labor during data input and to enable easy distinction of items for which input has not been completed. In addition, we added some items required for clinical work so the files could be used not only for registration with the JACVSD but also for clinical work.ResultsAll the items for the cases in 2005 and 2006 were input by the end of each year. Registration in the JACVSD in 2005 and 2006 was completed by the set deadline, except in one case in which the patient remained hospitalized at the time of the deadline.ConclusionsOur newly developed JACVSD-ready data files have increased the interest of surgeons in data entry and in collecting data. With the new system, we can manage patient data more easily and more effectively at low cost.

Chemical studies of pancreatic nonopaque concretions and protein plug

SummaryChemical studies were performed on all or part of four X-ray translucent (nonopaque) concretions and one protein plug to investigate a possible relationship between these substances, and to find the similarities and differences between these materials and pancreatic stone protein. Through elemental analysis, infrared absorption spectrometry, quantitative analysis of protein, and amino acid analysis, non-opaque concretions and protein plug were found to consist mainly of protein. One nonopaque concretion contained a very small amount of crystalline which differed greatly from calcite type calcium carbonate as observed in pancreatic calcified stones. The pattern of amino acid composition was very similar between the concretions and the protein plug: rich in acidic amino acids, but poor in basic and aromatic residues. The aspartic acid content was the highest among detected amino acids. Comparison of amino acid composition between the nonopaque concretions which we analyzed and the pancreatic stone protein reported from Sarles’ laboratory suggested that the concretions seem to contain some stone protein.