Gordon L. Hyde

Subclavian-axillary vascular trauma

Traumatic vascular injuries to the subclavian and axillary vessels are often associated with permanent neurologic impairment either by direct injury to the brachial plexus or by compression from an expanding hematoma. Prompt decompression of the plexus by evacuation of the hematoma may avoid permanent neurologic damage and decrease the morbidity of these injuries. We reviewed our experience with these injuries with particular reference to the effect of early decompression of the brachial plexus. From 1963 to 1984 we treated 40 patients. The causes of the injuries were penetrating trauma in 85% and blunt trauma in 15%. The results of arterial repair were excellent with only two failed repairs; neither resulted in severe ischemia. Two patients were suspected of having thrombosed venous repairs. Among the 12 patients with direct injury to the brachial plexus (partial or complete transection), only six had subsequent improvement of their neurologic dysfunction. In contrast, six of seven patients in whom there was only compression of the plexus by hematoma but no direct injury, had neurologic improvement following evacuation of the hematoma. This finding suggests that prompt decompression of the brachial plexus following these injuries may reduce the amount of neurologic impairment and reduce the morbidity of these injuries.

Recognition of arterial injury in elbow dislocation

The clinical presentation of patients with elbow dislocations was reviewed to identify those factors indicating an increased risk for arterial injury. Sixty-two patients were treated for 63 elbow dislocations between January 1981 and July 1991. Eight patients (13%) sustained a concomitant arterial injury involving the brachial (7) and radial (1) arteries. Three clinical findings, absence of a radial pulse, open dislocation, and presence of systemic injuries, were correlated with arterial injury. A palpable radial pulse was absent in six (75%) patients with an arterial injury but in only two (4%) with normal vessels (p less than 0.0001, chi square). Five (33%) open dislocations had an associated arterial injury, whereas three (6%) arterial injuries occurred in closed dislocations (p less than 0.006, chi square). Systemic injury occurred in five dislocations (63%) with arterial injuries and 14 dislocations (25%) without arterial injury (p less than 0.04, chi square). Multivariate analysis showed that absence of a radial pulse was the only factor that significantly predicted arterial injury (p less than 0.0001). Although most elbow dislocations are not associated with arterial injury, absence of a radial pulse or presence of an open dislocation or both should alert the clinician to the increased possibility of an associated vascular injury.

Jugular-axillary vein bypass for salvage of arteriovenous access

Stenosis or occlusion of the subclavian vein can cause incapacitating upper extremity swelling and venous hypertension in the patient with an arteriovenous (AV) access. A case of subclavian vein occlusion is reported that was treated with internal jugular-axillary vein bypass. This procedure resulted in salvage of the access and rapid resolution of the associated upper extremity swelling. It was concluded that jugular-axillary vein bypass should be considered in patients who have massive upper extremity edema resulting from a functioning AV access and ipsilateral subclavian vein occlusion. Patients undergoing creation of an AV access who have had previous temporary subclavian catheters or previous early failure of an AV access should have phlebography before surgery.

Hip disarticulation: Factors affecting outcome

Hip disarticulation, especially in patients with peripheral vascular disease, has been associated with high morbidity and mortality rates. This report describes patient characteristics that influence the clinical outcome of hip disarticulation. The medical records of all patients undergoing hip disarticulation from 1966 to 1989 were reviewed for surgical indication, perioperative wound complications, and postoperative deaths. Fifty-three patients underwent hip disarticulation for limb ischemia (10), infection (12), infection and ischemia (14), or tumor (17). The overall incidence of wound complications was 60%, and no significant differences were found among the groups. Prior above-knee amputation and urgent/emergent operations were significantly associated with increased wound complications (p less than 0.05). The overall mortality rate was 21%, ranging from 0% (tumor) to 50% (ischemia) and differed significantly among the groups (p less than 0.02). Mortality was significantly associated with urgent/emergent operations (p less than 0.01). Age, diabetes mellitus, and previous inflow procedures did not influence mortality rates. The presence of limb ischemia influenced mortality rates to a greater extent than did infection, and a history of cardiac disease was statistically predictive of death. Wound complications frequently accompanied hip disarticulation, regardless of operative indication, and were significantly increased by urgent/emergent operations and prior above-knee amputation. Hip disarticulation can be performed with low mortality rates in selected patients. Both limb ischemia and infection substantially increase operative mortality rates.

Capillary blood flow: videodensitometry in the atherosclerotic patient.

Recently the noninvasive technique of videomicroscopy has demonstrated qualitative morphologic changes in the nutritional skin capillaries in atherosclerotic (ATS) patients. The purpose of this study is to quantitatively examine the ATS microcirculation and effects induced by reconstructive surgery. Capillary blood flow velocity (CBV) of single vessels within the nail fold of the large toe was measured by dual-sensor videodensitometry in 14 ATS patients (age 45 to 80 years) and 11 age-matched controls. In addition to CBV, capillary diameter (CD) and the number of flow-active capillaries (FC) were also measured at constant temperature. Of the 14 patients, eight had measurements repeated 1 week after reconstructive surgery. The measurements were obtained at rest and then periodically after a 45-second period of pedal inflow occlusion. Respective group averages at rest for CBV, CD, and FC for the 14 ATS patients were as follows: 0.16 mm/sec, 10.5 micron, and 6.8 capillaries per field. Corresponding values for the control subjects were 0.10 mm/sec, 8.7 micron, and 5.3 capillaries per field. Combining CBV, CD, and FC into a measurement of volume capillary flow yielded a value of 281 pl/sec/mm2 for the patients and only 85 pl/sec/mm2 for the controls (p less than 0.02). Peak postocclusion CBV significantly increased, whereas FC significantly decreased relative to rest in the control group; however, the only patient group that responded to occlusion-induced ischemia was the postoperative group. In these patients there was a decrease in CBV and an increase in FC relative to rest. These responses are exactly opposite to those in the age-matched controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Carotid endarterectomy results from a state vascular society

PURPOSE This study analyzes the results of carotid endarterectomy (CEA) performed statewide by members of the Kentucky Vascular Surgery Society (KVSS). METHODS Between September 1, 1991 and September 1, 1993, 22 vascular surgeons in the KVSS submitted 1490 CEAs to the vascular registry. Follow-up data were obtained on 986 (66%) CEAs performed on 889 patients (average age, 68 years). RESULTS Carotid endarterectomy was performed on 505 men and 384 women. Indications for operation were asymptomatic carotid stenosis (43%), transient ischemic attack (TIA; 27%), amaurosis fugax (13%), stroke (11%) and nonhemispheric symptoms (6%). A total of 384 cases had primary closure, and 602 had patch reconstruction following CEA. The combined stroke-mortality rate was 2.3% (10 strokes and 13 deaths). The combined stroke-mortality rate of CEA was 2.1% for patients treated by academic surgeons and 2.3% for those treated by community surgeons. Deaths were due to stroke (4), sepsis (5), cardiac complications (2), intracerebral hemorrhage (1) and cancer (1). Five patients had postoperative TIAs. After CEA, duplex scan surveillance was performed in 629 (64%) patients, with 23 (3.6%) residual/recurrent stenosis (10, 50%-75%; 13, 75%-99%) detected; 5 undergoing reoperation. CONCLUSIONS These data support the efficacy and safety of CEA performed by a large number of vascular surgeons in both community and academic practice.

Nontraumatic lower-extremity acute arterial ischemia

BACKGROUND The outcome of arterial bypass reconstruction in the setting of acute arterial ischemia has not been well defined. METHODS This retrospective review consists of 71 consecutive patients (54 with native arterial thrombosis, 17 with graft thrombosis) who underwent an urgent/emergent arterial bypass reconstruction for acute arterial ischemia with threatened limb viability. RESULTS The 30-day mortality and major amputation rates were 9.9% and 7.1%, respectively. Death, limb loss, or both, were associated with a paralytic limb (P = 0.001) and congestive heart failure (P = 0.03). Overall, 45 of 71 (63%) patients were discharged with limb salvage and ambulatory function. Cumulative graft patency was 77% and 65% at 1 and 2 years, respectively, and closely approximated the 1- and 2-year limb-salvage rates of 76% and 63%, respectively. CONCLUSIONS Arterial bypass reconstructions appear warranted in acute arterial ischemia, in that a majority of patients retain a functional viable limb. Late graft thrombotic complications limit long-term benefit.

Massive upper extremity edema following vascular access surgery

We recently treated three patients with chronic renal failure who required subclavian vein cannulation with Uldall catheters following thrombosis of their arteriovenous fistulae. New arteriovenous fistulae were created in each patient following removal of the Uldall catheters. The patients were seen subsequently with massive, painful edema in the ipsilateral upper extremities from one to 10 weeks following creation of the arteriovenous fistulae. Radiographic studies documented stenosis or occlusion of the ipsilateral proximal subclavian vein. The arteriovenous fistula was ultimately ligated in each patient, which promptly resolved the pain and edema. Because subclavian vein thrombosis following temporary hemodialysis through an indwelling catheter is frequently asymptomatic until an arteriovenous fistula is constructed, venography should be considered in patients requiring upper extremity vascular access procedures. Demonstration of subclavian vein stenosis or occlusion would either preclude use of the upper extremity for an arteriovenous fistula or would require a concomitant procedure to relieve the venous obstruction.

Failure of antiplatelet therapy with ibuprofen (Motrin) to prevent neointimal fibrous hyperplasia.

To evaluate the effect of ibuprofen (Motrin) on the development of neointimal fibrous hyperplasia (NFH), 4 cm segments of expanded polytetrafluoroethylene (ePTFE) grafts with an internal diameter of 4 mm were implanted in the femoral arteries of 28 dogs. Three dogs served as controls and these grafts were removed at 7 to 14 days. The remaining 25 dogs were medicated with either intravenous (IV) or oral (PO) ibuprofen. The medicated dogs were grouped according to whether the ibuprofen was administered prior to or after graft implantation. The orally medicated dogs were also grouped according to whether the grafts were removed from 30 to 60 days after graft implantation. The grafts were analyzed for the amount of anastomotic initimal hyperplasia, pannus extension, thrombus deposition, and patency. Analysis of the data demonstrated no statistically significant differences among any of the treatment groups or the control group for the variables analyzed. We conclude that ibuprofen neither prevents nor retards the development of NFH. There was a trend toward less thrombus deposition in the animals that received oral ibuprofen preoperatively. There was also a trend toward higher patency in the animals that received ibuprofen prior to graft implantation, which most likely resulted from decreased thrombus and fibrin deposition.

Morphology Predicts Rapid Growth of Small Abdominal Aortic Aneurysms

This study evaluated CT scans of small abdominal aortic aneurysms (AAAs) (< 5 cm) to assess anatomic features associated with rapid expansion. Serial CT scans obtained at least 10 months apart (mean 15 months) from patients with small AAAs were reviewed. Each cross-sectional image of the AAAs was analyzed using a computer-assisted design program. The circumference of the AAA in each CT image was divided into eight equal arcs, from which the apparent radius of curvature (Rc) for each segment was calculated. Flattening of the wall curvature results in an increased segmental Rc. The CT scans of nine patients with expanding AAAs (expansion ≥0.5 cm/yr) were compared to those of 10 patients with stable AAAs (expansion <0.2 cm/yr). To adjust for differences in AAA size, the Rc for each segment was normalized by dividing each individual Rc by the average of the eight Res (RcAvg) calculated for that cross-sectional CT image. Analysis of variance showed that the left posterolateral segments in expanding AAAs had larger Rc/RcAvg ratios than those segments in stable AAAs (1.14 ± 0.19 vs. 0.80 ± 0.09, p < 0.02). Laplaces law indicates that the left posterolateral segment in AAAs that grow more rapidly is subjected to greater wall tension. Flattening in the curvature of the left posterolateral wall segment was significantly associated with an increased rate of expansion in small AAAs. This finding, readily derived from standard CT scan images, may predict which small AAAs are more prone to rapid expansion.