Alternate Papers (To be presented in case of a cancellation)

Forum Session

A1 Ultrafiltration to Decrease the Accumulation of Lung Water During Cardiopulmonary Bypass

DONALD J. MAGILLIGAN, JR.

and CHOKEN OYAMA*

Detroit, Michigan

Ultrafiltration is the removal of water and plasma concentration of electrolytes from blood by passage across a semi-permeable membrane. An Amicon Diafilter was placed between the arterial and venous lines of standard cardio-pulmonary bypass (CPB) in an attempt to determine the effect of ultrafiltra-tion on the accumulation of lung water during dilution perfusion CPB. Mongrel dogs were placed on CPB with non-blood prime and LRS added to maintain a flow of 100 ml/min/kg. Measurements made pre-bypass and 30 minutes post-bypass were: wedge pressure (Ppcw), colloid oncotic pressure (COP), COP-Ppcw, cardiac index (CI), and extravacular lung water (EVLW) determined by the thermal-dye indicator dilution technique wilh gravimetric correlation. Dogs were divided into two groups: Group 1 - two hours normothermic bypass, beating heart, left heart vented, and Group II - 90 minutes, cold, potassium, cardioplegic arrest and 30 minute recovery.

Results:

Group I:	Control	Ultrafiltration	Difference
Number	4	4	__
Fluid added	2350	2750	N.S.
Fluid out	180	2288	p = <.01
ΔCI	↓.20 L/min/m2	↓1.65 L/min/m2	N.S.
ΔEVLW	↑2.83 ml/kg	↑1.03 ml/kg	P = <.01
Group 11
Number	2	4	-
Fluid added	2775	3425	P = <.01
Fluid out	110	2710	p = <.01
ΔCI	↓0.09L/min/m2	↓0.65 L/min/m2	N.S.
ΔEVLW	↑3.40 ml/kg	↑0.95 ml/kg	P = <.05

There were no significant changes in Ppcw, COP, or COP-Ppcw in either group. The change in CI was similar in control and Ultrafiltration animals. Ultrafiltration during CPB allowed significantly less water to accumulate in the lungs compared lo control in both groups. When CPB is necessary in a patient with elevated EVLW, ultrafiltration may prevent further increases in EVLW and thereby decrease posl-operative pulmonary dysfunction.

*By invitation

Scientific Session

A1 Complications of Percutaneous Intraaortic Balloon Insertion

RAYMOND S. MARTIN, III*, ASHBY C. MONCURE,

MORTIMER J. BUCKLEY, W. GERALD AUSTEN,

GARY W. AKINS* and ROBERT C. LEINBACH*

Boston, Massachusetts

Early studies reported that percutaneous intraaortic balloons can be placed quickly and easily with minimal complications. To assess our experience with this technique, the records of the first 100 consecutive percutaneous inlra-aortic balloon insertion attempts at our hospital were reviewed. In 17 insertion attempts, the ballooon could not be passed retrograde inio the thoracic aorta, usually due to tortuosity or obstructive disease of the iliac arterties. Of the 83 patients in whom the balloon could be passed, 63 had no subsequent complications. Five balloons were successfully inserted, but the patient died immediately after insertion. Four patients developed in ischemic lower c.v Iremity on the side of insertion, requiring only balloon removal for limb salvage. Eleven patients developed an ischemic limb or false ancurysm requiring surgery for correction; of these, amputation was required in two extremities, and one patient died as a result of iliac artery perforation by the balloon.

Specific vascular injuries included six instances of femoral artery laceration with inlimal plaque elevation and thrombosis. Other injuries were false aneurysm with or without thrombosis, thrombosis without significant arterial injury, and iliac perforation. Techniques of repair included Ihrombectomy with lateral repair, vein or prosthetic patch angioplasly, and simple suture repair of false aneurysms.

Excluding patients who died immediately after balloon insertion, and thus had no follow-up, complications requiring surgery occurred in 11 of 95 attempted insertions (11.6%) in this series. This complication rate prompted us to examine indications and risk factors which might predict complications. In addition we have reviewed potentially preventativc techniques, such as prei-nsertion aortography and the use of a wire guide or long sheath for insertion.

Though percutaneous intraaortic balloon insertion has proved to be a valuable technique, a significant number of complications have been seen. Careful selection of patients and insertion by experienced hands should minimize complications.

*By invitation

A2 Repair of Post-Infarction Ventricular Septal Defect in the Elderly: Early and Long Term Results

RONALD W. WEINTRAUB, ROBERT L. THURER*

and JULIAN M. AORESTY*

Boston, Massachusetts

We performed 12 operations upon 11 consecutive elderly patients (pts) having postinfarction ventricular septal defect (VSD). All patients were older than 65 years (range: 66-82 years) and six were over 70. Nine underwent repair, with counterpulsation support, within one week of onset of the VSD. Of 8 anteriorly located VSDs, there were four survivors. Of three inferior defects, all survived, for an overall acute survival of 64%.

Our experience with respect to acute management suggests that 1) unless medical management results in continued improvement rather than stability alone, hemodynamic deterioration is inevitable, and survival for delayed repair is unlikely; 2) secondary operation for recurrent VSD and/or aneurysm formation can succeed despite high risk; and 3) technical details of infartectomy and graft preparation and placement are critically important in repair of inferior VSD.

The seven long term survivors were followed from 5 months to 7.5 years (mean: 2.8 years) by personal interview with patient or referring physician. There was one sudden death at 7.5 years in a previously well man. Of the remaining six paitnets, 5 are NYHA Class 1, and 1 is Class II. One lady, now 84, lives independently two years after repair.

We conclude that 1) most patients with VSD require early operation, 2) advanced age is no bar to successful VSD repair, and 3) long term results and quality of life may be excellent following VSD repair in the aged.

*By invitation