Long-term follow-up of limbs after use of intra-aortic balloon counterpulsation device.

There has been concern for the viability and function of the limb distal to the femoral artery access site after use of the intra-aortic balloon counterpulsation device (IABCD). We have studied the long-term (6 to 50 months) hemodynamic status in the lower limbs of 31 patients who received circulatory support with the IABCD. Since both limbs were classified according to the pressure changes induced by treadmill walking, comparisons with the unoperated leg could be affected. Nine of ten patients with insertion problems had satisfactory results at follow-up. One limb was lost as a result of the use of IABCD. Two patients had required femorofemoral bypass, three required use of the opposite leg because of gross femoral disease, one required thrombectomy, three lost distal pulses, and one developed groin phlebitis. All these patients (except the one requiring amputation) had satisfactory hemodynamics at follow-up. Of the 21 patients with no insertion problems, all had satisfactory hemodynamics at follow-up, and 16 of the 21 were normal. Three patients had better hemodynamic data in the balloon-access limb than in the contralateral limb at follow-up, suggesting that the surgery may have been salutary. We conclude that placement of the IABCD via the common femoral artery does not alter the long-term function of the ipsilateral limb if perioperative problems are avoided or handled appropriately.

Type of compression for reducing venous stasis. A study of lower extremities during inactive recumbency.

Determination of the optimal compression to reduce venous stasis was studied in terms of the amount of pressure and manner of application (graded or uniform pressure). Both lower extremities of seven inactive recumbent subjects were tested using transcutaneous Doppler ultrasonic measurement of femoral vein blood flow velocity. Optimal compression was defined as the externally applied pressure that produced the greatest increase in femoral vein flow velocity consistent with safety and the practicality of hospital use of elastic stockings. Optimal compression for elastic stockings to be used by hospitalized patients who spend substantial time in bed should be 18 to 8 mm Hg (ankle to midthigh). At this compression, average femoral vein blood flow velocity is increased to 138.4% of base line. Gradient compression at this level was found to produce a greater femoral vein flow velocity than the same amount of compression distributed uniformly over the lower extremity.

Risk assessment of pulmonary embolism by multivariate analysis.

A prospective study of 6,527 hospitalized patients was performed to evaluate the effectiveness of multivariate analysis of risk factors to correctly designate risk for pulmonary embolism. History of previous pulmonary embolism was the single most important factor. In patients without prior history, five factors emerged: inactivity, congestive heart failure, Doppler ultrasound evidence of deep-vein occlusion, female sex, and black race. Used together, these factors permitted a discrimination of risk such that 68.7% of pulmonary embolization was found to occur in 32.2% of the population designated as showing increased risk. Multivariate analysis of clinical factors improved assessment of risk, compared to the use of lower extremity findings alone, and proved to be useful in identifying individuals at increased risk for pulmonary embolism.

Femorofemoral bypass graft in intra-aortic balloon counterpulsation.

Femorofemoral arterial crossover grafts were used in three patients to avoid or correct limb ischemia during intra-aortic balloon counterpulsation. In retrospec, these grafts should have been used in two earlier patients in whom the balloon was removed prematurely. They are applied to the femoral artery just distal to the site of insertion of the balloon or the the balloon access graft. Removal of the graft at the time of the balloon removal is optional.

Carotid Endarterectomy without Angiography.

Each new technique for achieving and clarifying the diagnosis of arterial disease has stimulated an effort to establish its value as a tool for guiding surgical intervention. Noninvasive studies such as oculoplethysmography (OPG), phonoangiography, Doppler ultrasound spectral analysis, B-scan ultrasound, duplex ultrasound, computed tomographic (CT) scanning, magnetic resonance imaging (MRI), and transcranial Doppler have been seductive because these tools require no invasion of the. body or the artery of interest and are, therefore, eminently safe.

Metropolitan aeromedical service: state of the art.

This article summarizes the salient features of seven federally funded experimental helicopter aeromedical ambulance services. The lessons applicable to metropolitan aeromedical service are presented. Of over 30 currently operational helicopter ambulance services, eleven are discussed in detail because of a unique feature which characterizes each. Air rescue activity during the Los Angeles earthquake of February 1971, and hurricane Agnes in Pennsylvania in June 1972, are reported and assessed. The elements of a successful aeromedical service are: multi-mission approach; a small number of hospitals selected because of specialized facilities; adequate airborne equipment; aeromedical crewmen; communications with the ground; a reasonable cost; and operational hours coinciding with peak traffic.

The significance for morbidity and mortality of Doppler-absent pedal pulses.

The 1-month prognosis of 91 limbs with a pulseless foot in 49 patients was determined and related to elements of the physical examination, including Doppler ultrasonography. The risk factors that could predict loss of limb and death in this group of patients were determined. Gangrene and atrophy coupled with absent ultrasound signals predicted a 75% risk of loss of limb; this occurred despite attempted surgical intervention. Absence of Doppler signals in both ankle arteries was the strongest risk factor for predicting death. This is probably because ultrasound signals are absent only when arterial disease is far advanced. We conclude that Doppler ultrasound examination of the pulseless foot yields useful prognostic information relative to the fate of the limb and the patient who possesses such a limb.