Search PubMed⌕ Search

Biomedical subjects

B R Hopkinson

Publications and source records attributed to B R Hopkinson.

At least 109 records · Page 6Linked to original sources
PubMed1989

Do preoperative chlorhexidine baths reduce the risk of infection after vascular reconstruction?

Pathogenic organisms are frequently present on the skin of vascular patients and are a risk factor for postoperative infection. A randomised trial of preoperative antiseptic baths was performed in 64 high risk vascular patients to determine whether two chlorhexidine baths could reduce the incidence of postoperative sepsis. Although pathogenic organisms were isolated preoperatively in 35% of patients, the wound infection rate after chlorhexidine baths (26%) was greater, though not significantly, than after baths with non-medicated soap (11%). An alternative theory that infection arises via lymphatics in the limb was not confirmed when organisms could not be isolated from groin lymph nodes in a group of 35 patients. The case for preoperative antiseptic regimes in vascular surgery remains unproven.

Adult↗
PubMed1989

Intra-arterial thrombolysis using recombinant tissue plasminogen activator (r-TPA): the optimal agent, at the optimal dose?

Thirteen patients received 15 separate courses of intra-arterial (IA) r-TPA for acute and subacute peripheral arterial thromboses. Two patients received second courses: one following rethrombosis 2 weeks after the angioplasty of a residual stenosis, the other following rethrombosis 4 months after the initially successful thrombolysis. There were 10 men and 3 women with a mean age of 75.3 yrs (+/- 12.2). The median duration of ischaemia was 18 days (range 1-60), with five patients having severe ischaemia. All patients received IA r-TPA at a dose of 0.5 mg/h for a mean period of 26.2 hrs (+/- 12.6). Angiographic evidence of lysis was seen in all patients, however, this was insufficient to reperfuse the distal limb in two patients due to absence of run-off. Early rethrombosis occurred in both of these patients (less than 24 hrs, 11 days). There were no major complications, and minor groin haematomata occurred in four patients (three of whom underwent angioplasty). A further two patients rethrombosed despite angioplasty. One was successfully retreated and remains patent 5 months later, the other underwent surgical reconstruction. A partial systemic effect was confirmed by a reduction of plasminogen and fibrinogen to 66% of initial levels, and a reduction of alpha - 2-antiplasmin to 40% of initial levels. Haemoglobin was reduced by a mean 1.28 g/dl (+/- 0.82), however no transfusions were required, and no hypotensive periods occurred. Mean ankle/brachial systolic index (ABSI) was increased by 0.43 (+/- 0.24) overall.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1989

A comparison between visual and quantitative analysis in a prospective evaluation of labelled 111In leucocyte imaging in vascular infection.

In a continuing evaluation of 111In-oxine labelled leucocyte imaging in vascular surgery, we have studied 16 patients with a clinical diagnosis of possible vascular graft infection. We have evaluated both visual and semi-quantitative analysis of the images obtained and have interpreted these in the light of the subsequent clinical outcome. Full length or multifocal uptake was seen in six patients, all of whom eventually required graft excision with two limbs surviving, and one death. These patients had a significantly higher uptake ratio (median = 3.26) than those with either localized (median = 1.12; p = 0.0027) or negative images (median = 0.72; p = 0.0003). Of four patients showing localized uptake only, one required amputation for continuing sepsis. Six patients had negative images, and had normal DSA and CT scans. Uptake ratios could not distinguish between those with localized images and those with negative images. Computer generated vertical profiles aided separation of patients with presumed localized and negative images. Semi-quantitative analysis has proved to be a reliable method which should allow a more direct comparison of the efficacy of various investigative techniques and of the results of therapy, independent of intra-observer subjective bias.

Aged↗
PubMed1989

Transluminal iliac angioplasty with distal bypass surgery in patients with critical limb ischaemia.

Transluminal balloon angioplasty of the iliac artery was combined with a distal bypass graft procedure in 25 patients with critical ischaemia of the lower limb. Eleven patients had angioplasty in the operating theatre before a vascular graft and the remaining 14 patients had percutaneous transluminal angioplasty performed in the X-ray department before bypass surgery. The distal bypass grafts were 20 femoropopliteal and five femorofemoral grafts. Two patients died in the immediate postoperative period. Follow-up of patients ranged from 2 to 26 months with a graft patency of 63% at 12 months and 50% at 24 months but successful limb salvage rate of 75% at 12 and 24 months. Six patients required major amputations for failure of limb salvage. Transluminal iliac angioplasty is a valuable adjunct to distal bypass surgery by improving arterial inflow without the requirement for major aorto iliac surgery.

Actuarial Analysis↗
PubMed1989

Bipolar diathermy treatment of long saphenous vein varicosities.

A new technique of endoluminal diathermy of the long saphenous vein using a bipolar electrode is described. This is safer than conventional unipolar diathermy and histological examination of the diathermied veins shows similar appearances using unipolar and bipolar diathermy. Clinical assessment of both techniques yields similar results. Endoluminal bipolar diathermy is simple and relatively painless compared with conventional stripping of the long saphenous vein and can be recommended.

Electrocoagulation↗
PubMed1988

Local thrombolytic therapy of acute peripheral arterial ischaemia with tissue plasminogen activator: a dose-ranging study.

Low-dose streptokinase has been established as an alternative to surgery in selected patients with acute peripheral arterial ischaemia. Tissue plasminogen activator (t-PA) is responsible for normal plasma fibrinolytic activity and has recently become available for clinical use owing to recombinant DNA technology. It has the theoretical advantage of fibrin specificity, which may result in enhanced thrombolytic effects with greater safety. Twenty-three patients with recent lower limb arterial occlusions received t-PA over a tenfold range of concentrations and five patients received low-dose streptokinase. One month after treatment with t-PA or streptokinase 19 (68 per cent) patients had limb salvage, five (18 per cent) had required amputations and four (14 per cent) had died. Systemic fibrinolytic effects were variable but basically dose related. Haemorrhage occurred most frequently at the highest t-PA concentration and was major in four (17 per cent) cases, including a fatal stroke. Plasma fibrinogen concentration fell below 1.2 gl-1 in five (22 per cent) patients who received t-PA and was found to be a significant risk factor for haemorrhage, t-PA was an effective thrombolytic agent at all concentrations studied. The dose currently used in clinical studies at this institution is 0.5 mg h-1.

Acute Disease↗
PubMed1988

Risk factors in vascular surgical sepsis.

The risk factors for sepsis after vascular surgery were studied in 100 consecutive patients with lower limb arterial ischaemia. Patients were randomised either to a short or long course of antibiotic prophylaxis with amoxycillin/clavulanic acid combination (Augmentin). Pathogenic organisms were isolated from the skin preoperatively in 39 (36%) cases, significantly more frequently in patients with ischaemic rest pain and skin necrosis (66%) than rest pain alone (21%) (P = 0.0004) or claudication/aneurysm (11%) (P = 0.0001). All but three organisms isolated (5%) were sensitive to amoxycillin/clavulanic acid. A wound infection occurred after 21 (19%) reconstructions, significantly more frequently both in patients suffering rest pain with skin necrosis (P = 0.001) and rest pain without skin necrosis (P = 0.04) compared with claudication/aneurysm. Sixteen of the 21 patients with a wound infection had at least one organism isolated from their skin preoperatively (P = 0.0001). Twelve patients (57%) had a similar organism isolated from the skin preoperatively and from the postoperative wound infection. Reducing the course of antibiotic prophylaxis from 5 days to 3 doses did not significantly increase the infection rate. The only other significant risk factor for sepsis was increasing age of the patient. Although prophylaxis is undisputed in patients having synthetic grafts, antibiotics may not be as important in the prevention of wound sepsis as had been thought. The role of antiseptic agents requires further evaluation.

Adult↗
PubMed1988

A 10-year review of false aneurysms in Nottingham.

Over a 10-year period, twenty-nine patients who developed false aneurysms were reviewed retrospectively. The diagnosis was delayed for as long as 7 months in the eight patients who developed aneurysms following trauma. However, all these patients had an excellent outcome after surgery. The results were also good in patients with non-infected false aneurysms after vascular reconstruction, with 17 of the 19 patients having the affected limb saved by remedial surgery. The main principle of remedial surgery was to perform the simplest surgical procedure possible. The results in infected false aneurysms were poor and management should be considered along the lines laid down for graft infection. The incidence of false aneurysms may be reduced by the use of suitable non-absorbable sutures, prevention of tension at an anastomosis and prevention of infection. However, degeneration of the arterial wall is thought to be a major cause of false aneurysms and is, of course, beyond control. Recent technical advances such as digital subtraction angiography, labelled leucocyte scanning and computed tomography have all contributed to improvements in the management of false aneurysms.

Adolescent↗
PubMed1987

Early results of low dose intra-arterial streptokinase therapy in acute and subacute lower limb arterial ischaemia.

Thirty-two patients with acute and subacute limb-threatening peripheral arterial ischaemia were treated with low dose intra-arterial streptokinase infusions. The mean duration of infusion was 38 h. Six patients developed pericatheter thrombosis and two had distal embolization of fragments of thrombus but in all cases these responded to repositioning the catheter and continuing the infusion. Five patients developed groin haematomata and in three of these there was evidence of a systemic fibrinolytic effect from the streptokinase with plasma fibrinogen reduced below 1 g/l. The most serious complication was perforation of the popliteal and tibial arteries which occurred on two occasions and required cessation of the infusion. Twenty-two patients (69 per cent) achieved limb salvage, eight (25 per cent) suffered a major amputation and two (6 per cent) died. The outcome was not related to the site, nature or duration of the arterial occlusion but patients with loss of sensation or paralysis of the affected limb were significantly less likely to obtain limb salvage (P = 0.001). For occlusions greater than 30 cm in length a new technique was used where the thrombus was lysed from distal to proximal in short lengths by gradual catheter withdrawal. This was successful in five out of six cases. Low dose intra-arterial streptokinase has been confirmed as an effective, relatively safe method of treatment in recent arterial ischaemia and can be recommended in situations where the results of surgery may not be favourable. In particular, patients with arterial thromboses and no distal run-off, distal and late arterial emboli, thrombosed popliteal aneurysms and patients after a failed embolectomy, have all been shown to respond to thrombolytic therapy with intra-arterial streptokinase.

Adult↗
PubMed1987

Defective fibrinolysis: a risk factor in early femoropopliteal graft thrombosis.

Resting plasma fibrinolytic activity and fibrinolytic activity after stimulation by 10 min of venous occlusion (fibrinolytic potential) were estimated in 51 patients before femoropopliteal reconstructive surgery. Twelve patients suffered a graft thrombosis in the first month. Resting plasma fibrinolytic activity was similar in patients with thrombosed grafts and those with functioning grafts. However reduced fibrinolytic potential was found to be a risk factor for graft thrombosis in the month after surgery (P = 0.01). Other risk factors were increasing age (P = 0.007) and the indication for surgery (P = 0.03). Thirty-four patients whose grafts were functioning after 1 month were followed up for a mean of 9 months. A further eight grafts thrombosed. Neither fibrinolytic activity nor fibrinolytic potential were found to be risk factors for late graft thrombosis. Fibrinolytic potential has been shown to be an independent risk factor for early graft thrombosis. Perioperative fibrinolytic stimulation might be a method of improving femoropopliteal graft patency.

Aged↗
PubMed1987

Late results of silicone rubber perianal suture for rectal prolapse.

Twenty-one patients were reviewed five to 12 years after silicone rubber perianal suture for rectal prolapse. Sixteen patients (76 percent) were continent with control of prolapse and two patients (9 percent) suffered only from occasional prolapse or incontinence. Rebanding for silicone cutout or fracture was required in four patients and a second rebanding operation was needed in two. Silicone rubber perianal suture for rectal prolapse stands the test of time and might be recommended for more widespread use in younger patients.

Adult↗
PubMed1987

Popliteal artery perforation during low dose intra-arterial streptokinase infusion.

There has been a recent increase in the use of low dose intra-arterial streptokinase infusion for the management of patients with acute peripheral arterial occlusions. Though serious complications using this technique occur less frequently than when using systemic thrombolytic therapy, a case is reported where the catheter used to infuse streptokinase perforated the popliteal artery 36 hours after the infusion commenced. The use of softer arterial catheters and restriction of patient movement where possible may prevent the recurrence of this previously unreported hazard.

Catheterization↗
PubMed1987

Low dose intra-arterial streptokinase and acylated plasminogen-streptokinase activator complex: a retrospective review of two thrombolytic regimes in recent peripheral arterial ischaemia.

Thrombolytic therapy was used for 57 patients with acute and sub-acute lower limb arterial ischaemia. In the first 34 patients a new thrombolytic agent, acylated plasminogen-streptokinase complex (BRL 26921) was assessed. Following this, 23 patients received low dose intra-arterial streptokinase. The two thrombolytic regimes have been analysed retrospectively. There were differences observed between the two groups in the type of patients treated and in the severity of limb ischaemia. Of the patients receiving BRL 26921, five (15%) had complete, and three (9%) partial lysis of the occluding thrombus. Serious bleeding occurred in six (18%) and minor bleeding in ten (29%) patients. After 30 days, twelve patients (35%) had limb salvage and eleven (32%) had died. Fifteen patients (65%) receiving intra-arterial streptokinase had lysis of the occluding thrombus. Minor bleeding was observed in three patients (13%). After 30 days, 15 (65%) had limb salvage and three (13%) had died. Patients receiving BRL 26921 had a significantly greater reduction in plasma fibrinogen and plasminogen concentrations during treatment which may have accounted for the bleeding complications. At the dose used, BRL 26921 had no demonstrable fibrinogen sparing effect. Improved lysis rates with fewer bleeding complications might be achieved by reducing the dose of BRL 26921. Low dose intra-arterial streptokinase has been confirmed as a safe, effective method of thrombolysis in recent peripheral arterial ischaemia.

Aged↗
PubMed1986

The systemic fibrinolytic effect of BRL 26921 during the treatment of acute peripheral arterial occlusions.

BRL 26921 is a new acylated streptokinase-plasminogen complex which may have a more specific local thrombolytic effect than streptokinase or urokinase. 34 patients with acute peripheral arterial occlusions were given eight hourly bolus injections of 5 mg BRL 26921 for up to 72 h. Systemic fibrinolysis was observed in all patients yet in only 24% was the occluding thrombus lysed. 44% of the patients had haemorrhagic complications and 24% suffered further thrombotic events during or soon after treatment. There was no correlation between the degree of systemic fibrinolysis produced and dissolution of the thrombi. The degree of systemic fibrinolysis did not affect the complication rate. There is no evidence from this study that BRL 26921 has a specific local thrombolytic effect.

Aged↗
PubMed1986

Major amputation compared with graft occlusion as the end point for assessing results of bypass surgery in lower limb ischaemia.

Cumulative graft patency rates calculated using graft occlusion as the end point are the standard method of presenting results of bypass surgery for lower limb ischaemia. The problems of using graft occlusion as the end point are that this is not easily documented and it gives no indication of the condition of the patient's limb after the graft occludes. The date of amputation is a well defined end point and it means treatment has failed. It is used to calculate cumulative limb salvage rates. Using the two techniques to assess different risk factors (age, calf vessel run-off, diabetes, position of distal anastomosis and hypertension), it was found that the limb salvage rate was a better indicator of patient progress. Whereas graft patency rates for diabetics and non-diabetics were similar (chi 2 = 0.8, P greater than 0.1), diabetics had a higher amputation rate and the limb salvage rate was significantly worse (chi 2 = 5.0, P less than 0.05). Cumulative survival is rarely presented in vascular series but it could be used as an indicator of the general condition of patients being selected for bypass surgery. The cumulative survival of diabetics was 23 per cent (s.e.m. +/- 12 per cent) at four years, while for non-diabetics this was 55 per cent (s.e.m. +/- 15 per cent), (chi 2 = 10.6, P less than 0.001). Diabetic patients have such different limb salvage and survival rates compared with non-diabetic patients that their results should be presented separately. A better indication of patient progress following bypass surgery is obtained if limb salvage rates and survival rates are reported as well as graft patency rates.

Aged↗