Risk of recurrent biliary tract disease after cholecystectomy in patients with duodenal diverticula.

OBJECTIVE: To determine if the presence of duodenal diverticula predisposes to the development of common bile duct stones. DESIGN: Cohort study; median follow-up, 10.0 years (25th and 75th percentiles, 5.2 and 16.1 years, respectively). SETTING: Tertiary care center. PATIENTS: One hundred fifty-seven patients with radiologically diagnosed duodenal diverticula who had undergone cholecystectomy from 1950 through 1987 and were asymptomatic at the initiation of follow-up. MAIN OUTCOME MEASURES: All patients were followed up for evidence of recurrent biliary tract disease to the following end points: (1) evidence of choledocholithiasis demonstrated by radiologic surgical, or biochemical means and (2) clinical or biochemical evidence of biliary pancreatitis. RESULTS: Of the 157 patients in the study cohort, 13 patients were categorized as having had recurrent biliary tract disease. Using the Kaplan-Meier survivorship method, the cumulative probabilities of recurrent biliary tract disease in patients with radiologically diagnosed duodenal diverticula were 3.6% at 5 years (95% confidence interval, 0.5-6.9), 5.5% at 10 years (95% confidence interval, 1.5-9.4), and 10.2% at 15 years (95% confidence interval, 3.8-16.7). Age, common bile duct exploration and choledochotomy, and the presence of common bile duct dilatation were not found to be significantly associated with recurrence based on a univariate analysis of risk factors by means of the log-rank statistic. CONCLUSIONS: For patients with radiologically diagnosed, second-portion duodenal diverticula, the risk of developing recurrent bile duct stones after cholecystectomy is lower than has been suggested in previous studies. In the absence of concurrent choledocholithiasis, sphincterotomy or biliary bypass at the time of cholecystectomy seems unwarranted.

Intravenous digital subtraction angiography versus computed tomography in the assessment of abdominal aortic aneurysm.

Results of preoperative investigation of 127 patients who underwent elective aortic aneurysm repair during a 3-year period were examined and compared with findings at operation. The accuracy of preoperative computed tomography (CT) and intravenous digital subtraction angiography (DSA) in assessing proximal and distal aneurysm extent was compared. From a total of 118 CT scans, ten of 12 suprarenal aneurysms were correctly predicted, with 11 false positives (positive predictive value 48 per cent, sensitivity 83 per cent, specificity 90 per cent). After 103 DSA investigations, six of ten suprarenal aneurysms were correctly predicted with one false positive (positive predictive value 86 per cent, sensitivity 60 per cent, specificity 99 per cent). Using CT, 30 of 54 aneurysmal iliac arteries were correctly diagnosed with 20 false positives (positive predictive value 60 per cent, sensitivity 56 per cent, specificity 88 per cent). Thirty-six of 48 aneurysmal iliac arteries were diagnosed correctly using DSA, with 32 false positives (positive predictive value 53 per cent, sensitivity 75 per cent, specificity 79 per cent). Intravenous DSA also provided useful information about renal and peripheral occlusive disease. Both investigations have their own specific limitations; clinicians should be aware of these when ordering and interpreting them.

Common femoral artery volume flow in peripheral vascular disease.

Common femoral artery volume flow was measured at rest and during postocclusive reactive hyperaemia in 80 normal subjects and 67 patients with radiological evidence of occlusive peripheral vascular disease. At rest, means(s.d.) common femoral artery volume flow in normal subjects (344(135) ml/min) and all patients with peripheral vascular disease (401(168) ml/min) was not significantly different. During postocclusive reactive hyperaemia, mean(s.d.) peak flow was significantly higher in normal subjects (1951(438) ml/min) than in patients with peripheral vascular disease (996(457) ml/min) (P less than 0.01). Common femoral artery volume flow in patients with critical ischaemia and intermittent claudication did not differ at rest but mean(s.d.) peak flow in patients with critical ischaemia (697(276) ml/min) was significantly lower than in claudicants (1131(447) ml/min) (P less than 0.01). Mean(s.d.) resting common femoral artery volume flow in limbs with femoropopliteal disease (457(185) ml/min) was significantly greater than that in limbs with occlusion of the aortoiliac segment (308(130) ml/min) (P less than 0.01). However, this difference did not persist during postocclusive reactive hyperaemia. A hyperaemic index, calculated from the hyperaemic responses to below knee and whole limb ischaemia, was used to quantify segmental perfusion during postocclusive reactive hyperaemia. The mean(s.d.) value in normal subjects, 46(9) per cent, and in those with aortoiliac disease, 52(12) per cent, indicated approximately equal perfusion of the above and below knee limb segments. In those with femoropopliteal disease the mean(s.d.) hyperaemic index was 17(13) per cent, revealing relative hypoperfusion of the below knee segment.

Nifedipine in patients with peripheral vascular disease.

The calcium antagonist nifedipine has been studied in a group of patients with intermittent claudication. In a long-term double blind, placebo controlled trial in 27 patients there was no effect on exercise tolerance as measured by pedal ergometry and only a limited improvement in symptom score on double dose nifedipine. Common femoral artery volumetric blood flow (measured by duplex ultrasound) was unaffected. The acute effects on blood flow were also studied, with a mean increase of 23% in common femoral artery blood flow 30 min after sublingual nifedipine. The administration of nifedipine to patients with peripheral vascular disease will not adversely affect claudication symptoms, and may result in an acute improvement in lower limb blood flow. Nifedipine is a suitable antihypertensive in patients who suffer from intermittent claudication.

Digital and radial artery blood flow in patients with Raynaud's phenomenon in response to nifedipine.

The effect of nifedipine on haemodynamic changes in the hand after cooling in 10 patients with Raynaud's phenomenon is assessed. Nifedipine reduced the fall in digit blood flow induced by cooling and limited the increase in pulsatility index (a measure of peripheral resistance). There was good correlation between digital arterial inflow (measured by strain gauge plethysmography) and radial artery pulsatility index (measured by Doppler waveform analysis).

Nifedipine in patients with Raynaud's syndrome--effects on radial artery blood flow.

The acute effect of nifedipine on hand blood flow of 20 patients with Raynaud's phenomenon, treated in a double-blind, crossover study, is reported. Radial artery blood flow was found to correlate with the reciprocal of the pulsatility index. This simple Doppler technique gave an instantaneous record of the effect of cooling on hand blood flow. In patients with Raynaud's phenomenon, nifedipine prevents the reduction of hand blood flow that is induced by cooling in untreated patients.

The effects of nifedipine on blood flow in peripheral vascular disease of the lower limbs.

The effects of nifedipine on blood flow to the lower limb have been investigated in 19 patients with calf claudication, and in 8 patients with critical leg ischaemia, using Doppler techniques. In claudicants, common femoral artery blood flow increased by 55% after sublingual nifedipine, despite a fall in systolic blood pressure and no alteration in the ankle/brachial index. In patients with critical ischaemia given intravenous nifedipine, common femoral blood flow increased to reach a peak 90 minutes after the start of the infusion. The femoral artery pulsatility index, derived from the Doppler waveform, is a reliable guide to changes in blood volume flow.

Measurement of volume flow in the human common femoral artery using a duplex ultrasound system.

A duplex ultrasound system was used to measure volumetric flow in the human common femoral artery. The accuracy of the technique was validated using a flow rig. The average resting common femoral artery flow rate in a population of subjects clinically unaffected by peripheral vascular disease was 350 +/- 141 mls min-1. Although mean common femoral artery diameter was greater in males (10 +/- 0.9 mm) than in females (7.8 +/- 0.7 mm) (p less than 0.01), there was no significant difference in resting blood flow. Repeated measurements in individual subjects showed a high variability, largely due to physiological fluctuations (75 percent of total variability). There was a close correlation between volume flow and the reciprocal of pulsatility index (100/PI). In normal subjects 100/PI represents a simpler method of determining individual changes in blood flow. The temporal variations in volume flow during periods of reactive hyperaemia had a characteristic profile, which was dependent on the duration of circulatory arrest. The data derived from the resting hyperaemia flow profile provides normal ranges for future comparison with patients suffering from peripheral vascular disease.

Post-arterial reconstruction edema, are lymphatic channels to blame?

Edema which follows successful arterial reconstruction of a previously ischemic lower limb is a common observation. Most patients have no long term difficulty, but this side effect requires considerable attention to leg care and frequently delays resumption of normal activity. Earlier studies suggested various causes. This study looked into lymphatic causes. 125I RIHSA clearance was monitored in 4 patients who developed edema following femoropopliteal bypass, and 5 patients who did not develop edema following other vascular procedures. In the edematous limbs following successful femoropopliteal bypass grafting, the mean T 1/2 was 18.4 hours when compared to 52.7 hrs. in other procedures (p less than .025). This indicates increased lymphatic flow of the distal superficial lymphatics. It is concluded that post reconstruction edema is not due to lymphatic disruption but is instead of multifactorial origin.

Lymphatic flow in humans as indicated by the clearance of 125I-labeled albumin from the subcutaneous tissue of the leg.

Since the removal of albumin from the extracellular space and its return to the vascular compartment is the essential function of the lymphatic system, the rate at which it is removed from the interstitial tissue may be regarded as a means of estimating lymphatic efficiency. An objective measure of lymphatic function can be obtained by monitoring the rate of clearance following injection of 125I-labeled albumin (RIHSA) from the subcutaneous tissue of a limb. The clearance of 125I-RIHSA from lower limb was monitored in a group of patients with normal limbs, patients with unilateral edema due to deep vein thrombosis, and patients with bilateral edema due to hypoproteinemia. The mean T1/2 in normal legs was 32.7 hr, compared to 23.7 hr in edematous limbs due to deep vein thrombosis and 19.4 in edematous limbs due to hypoproteinemia. There is a clear-cut difference in clearance rate between edematous and nonedematous limbs. This suggests that lymphatic flow is increased in edema due to venous obstruction and hypoproteinemia.

Muscle relaxation during abdominal surgery.

A self-retaining surgical retractor has been modified by incorporating a strain gauge device linked to a digital display meter. This instrument is capable of continuously monitoring abdominal wall relaxation during surgery and should prove useful in a variety of routine and investigative procedures.

Blood flow measurement in patients with intermittent claudication.

Modified isotope clearance tests for the objective investigation of intermittent claudication of the lower limb were performed in 14 normal subjects with clinically patent arteries and 9 patients with calf claudication and arteriographically confirmed peripheral vascular occlusion. The tests involved a standard exercise performed in the supine position. During rest periods the limb under test was subjected to simultaneous venous occlusion plethysmography. In the patients with intermittent claudication, results were abnormal when compared with those of the normal group. The modified testing procedure described gave discriminatory results for each group. Their usefulness in monitoring disease progression, treatment benefit, and patient selection for surgery is discussed.

Bypass vein grafts in patients with distal popliteal artery occlusion.

The results obtained by placing reversed autogenous saphenous vein bypass grafts in either isolated popliteal artery segments or tibial vessels distal to the popliteal artery segments or tibial vessels distal to the popliteal artery are compared. Fifty-five patients with arteriosclerotic peripheral vascular disease who were threatened with limb loss were followed up from six months to nine years prior to this report. The success rate at one year was 94 per cent for the isolated popliteal segment grafts and 73 per cent for the tibial vessel grafts. The success rate after four years was 70 per cent for the isolated popliteal segment grafts and 63 per cent for the tibial vessel grafts. The clinical factors associated with the success of isolated popliteal segment bypass grafts and the factors apparently associated with failure of vein grafts in both of these groups with very poor distal arterial outflow are discussed. Our results suggest that either an isolated popliteal artery segment graft or a tibial vessel graft is a satisfactory means of treating these patients; however, a graft to an isolated popliteal segment is probably preferable to a graft to a tibial artery.