Search PubMed⌕ Search

Biomedical subjects

P C Clifford

Publications and source records attributed to P C Clifford.

At least 19 recordsLinked to original sources
PubMed1990

Impact of duplex scanning on carotid endarterectomy.

Duplex ultrasound permits safe and accurate assessment of the extracranial vasculature. This paper reports the change in patterns of referral to a specialized vascular unit following its introduction; increased referrals were seen in all specialties except neurology. A widely available and reliable duplex service has revealed more extracranial vascular disease than was previously recognized, and has increased referrals for carotid endarterectomy, thereby increasing surgical workload.

Adult↗
PubMed1990

Varicose vein surgery using a pneumatic tourniquet: reduced blood loss and improved cosmesis.

A prospective controlled randomised study has been performed of 100 consecutive patients undergoing varicose vein surgery. One group underwent saphenofemoral flush ligation and multiple lower leg avulsions with the leg exsanguinated with a Rhys-Davies cuff, and ischaemia maintained with a pneumatic tourniquet. The other group underwent identical surgery but with a 30 degree head down tilt only. Blood loss was significantly less (13.5 +/- 12 ml vs 133 +/- 78 ml; P less than 0.01) and postoperative cosmesis was significantly improved in patients in the tourniquet group. Operating time was similar (27 +/- 11 min vs 30 +/- 13 min) in the two groups.

Esthetics↗
PubMed1989

Phaeochromocytoma and abdominal aneurysm: confirmation of diagnosis after aortic surgery using mIBG imaging.

Four cases of dissecting thoracic aneurysm associated with phaeochromocytoma have been reported in the World literature, of which only one survived surgery. We report what we believe to be the first case of intra-adrenal phaeochromocytoma presenting as a leaking abdominal aneurysm; which is of further interest as post-reconstruction 131-I meta-Iodobenzylguanidine (mIBG) imaging confirmed the existence of the tumour, despite equivocal urinary metanephrines.

3-Iodobenzylguanidine↗
PubMed1989

Limitations of percutaneous transluminal angioplasty in the treatment of femoro-distal graft stenoses.

Non-invasive follow-up of 94 femoro-distal reconstructions has identified 14 graft related stenoses (4 proximal anastomotic, 4 intragraft and 7 distal anastomotic). Stenoses treated by percutaneous transluminal angioplasty (PTA) recurred by 6 months. Stenoses treated by surgical revision remained satisfactory with a mean follow-up of 13 months. In this series, formal surgical revision appears to be superior to PTA for the treatment of graft stenoses.

Aged↗
PubMed1989

After surgery for breast cancer: which mode of surveillance?

Five hundred and ten women attending a specialized breast clinic for follow-up after surgery of early breast cancer (Stage I and II) have been studied. Recurrence was found most often (58%) in symptomatic women who returned to the clinic earlier than planned. Only 3% of asymptomatic patients had recurrent disease. It is concluded that counselling in symptoms of recurrent breast cancer would allow more efficient follow-up.

Breast Neoplasms↗
PubMed1988

Inflow site: its effect on femoropopliteal and distal graft patency.

In a series of 245 vein grafts, results of 163 from the common femoral artery were compared with 82 from the proximal superficial femoral artery. Groups were comparable for risk factors, except that significantly more of the superficial femoral artery group were anastomosed to a single calf vessel (P less than 0.02). Early technical failure was similar in both groups (14 per cent common femoral artery, 12 per cent superficial femoral artery, P = n.s.). Cumulative life table patency rates at 1 and 3 years were 77 per cent and 72 per cent in common femoral artery grafts, and 80 per cent and 70 per cent in superficial femoral artery grafts (P = n.s.). Analysis of 92 veins in situ (65 common femoral artery and 27 superficial femoral artery) showed 1-year patency rates of 75 per cent in common femoral artery grafts and 79 per cent in superficial femoral artery grafts (P = n.s.). These results suggest that the proximal superficial femoral artery is a safe inflow site for distal bypasses.

Adult↗
PubMed1987

Non-invasive assessment of lower limb ischaemia by blood velocity wave-form analysis.

Clinical examination combined with angiography is conventionally used to assess lower limb arterial disease. The shape of the blood velocity wave form in the common femoral artery varies with the extent of proximal arterial disease, suggesting that wave-form analysis may provide additional haemodynamic information of potential value in surgical decision-making. This paper studies the use of two methods of wave-form analysis, pulsatility index and Laplace transform analysis, to assess lower limb arterial disease. The blood velocity wave form was measured non-invasively at the common femoral artery using a locally developed mean frequency processor and a commercial 9.5 MHz bidirectional Doppler ultrasound unit. Wave forms from 70 limbs (35 patients) with suspected atherosclerotic arterial disease and from 20 normal limbs with no history or signs of disease were studied. Both methods of wave-form analysis provided a statistically significant separation between patients with severe and moderate disease as assessed angiographically (P less than 0.001). These results suggest that significant aorto-iliac disease can be virtually excluded by a normal common femoral wave form. Furthermore, wave-form analysis may have an important role in the follow-up of patients after bypass grafting or iliac angioplasty and in the detection of presymptomatic aorto-iliac disease.

Adult↗
PubMed1987

Salvage autotransfusion in aortic surgery: initial studies using a disposable reservoir.

Transmission of disease by allogeneic transfusion can be avoided using several techniques by which a patient receives his own blood. Sixty patients undergoing aortic surgery consented to salvage interoperative autotransfusion. A mean of 895 ml shed blood was reinfused under full heparinization, representing 12-74 per cent of total blood loss. Bank blood requirements fell from 4.9 units to 3.4. No important haematological or clinical complications were noted (including coagulation studies) but haemolysis was detected 4 h postoperatively by plasma haemoglobin levels of 0.05 +/- 0.03 g/dl. This preliminary study confirms the applicability of salvage autotransfusion during elective vascular surgery by demonstrating an appreciable saving in bank blood transfusion (70 per cent).

Aorta↗
PubMed1987

Duplex ultrasound monitoring of arterial grafts: prospective evaluation in conjunction with ankle pressure indices after femorodistal bypass.

Duplex scanning and ankle brachial pressure indices have been used to objectively assess 94 femoro-distal bypass grafts 4-8 weeks postoperatively. Twenty grafts were occluded. Of the 74 patent grafts, three distinct groups could be identified on the basis of the non-invasive examination. Group 1. Patent grafts with no evidence of haemodynamically significant disease. Group 2. Patent grafts with localised disease. Group 3. Patent: haemodynamically failed grafts. Ankle brachial pressure indices alone could not differentiate between occluded grafts and grafts that were patent: haemodynamically failed (group 3), or adequately separate between grafts in groups 1 and 2. Duplex scanning when combined with pressure indices identified patent grafts "at risk" due to the presence of haemodynamically significant disease. Life table analysis demonstrated appreciable differences in event free survival between group 1 grafts and "at risk" grafts (groups 2 and 3). Duplex scanning is ideal for regular postoperative surveillance and complements the use of ankle brachial pressure indices in the follow-up of femoro-distal grafts.

Actuarial Analysis↗
PubMed1987

Duplex ultrasound assessment of femorodistal grafts: correlation with angiography.

Fifty-eight grafts have been assessed using duplex scanning and ankle brachial pressure indices. This assessment is compared with the findings by angiography. Eighteen grafts were occluded and 40 patent. Duplex scanning defined graft status with a greater accuracy than pressure indices. Pressure indices alone would not differentiate "satisfactory" grafts from those with localised, haemodynamically significant disease. Only 55% of those grafts with localised stenoses demonstrated a fall of greater than 0.2 in ankle brachial pressure index after exercise. When the information obtained using pressure indices and duplex scanning was combined non-invasive assessment had a sensitivity of 86% and specificity of 94% for detection of localised, haemodynamically significant disease in patent grafts. Haemodynamically significant disease, as defined by angiography, can be detected and localised with duplex scanning complementing the use of pressure indices in graft assessment.

Aged↗
PubMed1987

The success of in situ vein grafting: early results in comparison with the reversed vein technique.

In a 6-year retrospective analysis of 341 consecutive femorodistal autogenous vein bypasses, results from 104 in situ veins (IS) were compared with 209 reversed veins (RV). The groups were comparable for age, sex, diabetes, indication for surgery and calf vessel run-off, but a significantly higher proportion of the in situ group had a lower distal anastomosis (16% IS, 6% RV, chi 2 = 7.1 P less than 0.01). Overall, operative mortality was 2% and early graft failure was similar in both groups (11% IS, 12% RV, P = NS). Cumulative graft patency rates were 74% IS, 79% RV at one year and 71% IS, 71% RV (P = NS) at three years. Cumulative limb survival rates were 81% IS, 85% RV at one year and 79% IS, 81% RV [P = NS) at 3 years. These results demonstrate that the in situ technique has been used in a wider variety of patients and yielded similar early and intermediate term results to reversed vein.

Adult↗
PubMed1987

Acute abdominal pain: computer aided diagnosis by non-medically qualified staff.

This report explores the role of computer aided diagnosis in acute abdominal pain when applied by non-medically qualified personnel. Clinical features of 153 patients (75 males, 78 females, aged range 6-92 years, median 35 years) suffering from less than one weeks' abdominal pain were recorded. Junior doctors' diagnostic accuracy with (65 cases) and without (70 cases) structured computer history sheets were compared with first year clinical medical students using the computer system (46 cases: 28 also seen by doctor, 18 cases student only). These students had no previous surgical training or experience. Doctors' diagnostic accuracy of 51% rose significantly to 69% with the use of structured history forms (chi 2 = 4.53, P = less than 0.05). Computer assisted clinical students' diagnostic accuracy matched the improved doctors' accuracy (69.5%). These results have implications not only for medical education but also for isolated paramedical personnel who should be supplied with structured diagnostic forms and, where appropriate, a microcomputer.

Abdomen, Acute↗
PubMed1986

Computer aided diagnosis of acute abdominal pain: a multicentre study.

A multicentre study of computer aided diagnosis for patients with acute abdominal pain was performed in eight centres with over 250 participating doctors and 16,737 patients. Performance in diagnosis and decision making was compared over two periods: a test period (when a small computer system was provided to aid diagnosis) and a baseline period (before the system was installed). The two periods were well matched for type of case and rate of accrual. The system proved reliable and was used in 75.1% of possible cases. User reaction was broadly favourable. During the test period improvements were noted in diagnosis, decision making, and patient outcome. Initial diagnostic accuracy rose from 45.6% to 65.3%. The negative laparotomy rate fell by almost half, as did the perforation rate among patients with appendicitis (from 23.7% to 11.5%). The bad management error rate fell from 0.9% to 0.2%, and the observed mortality fell by 22.0%. The savings made were estimated as amounting to 278 laparotomies and 8,516 bed nights during the trial period--equivalent throughout the National Health Service to annual savings in resources worth over 20m pounds and direct cost savings of over 5m pounds. Computer aided diagnosis is a useful system for improving diagnosis and encouraging better clinical practice.

Abdomen↗
PubMed1986

A system for rapid analysis of the femoral blood velocity waveform at the bedside.

The shape of the arterial blood velocity waveform varies with atherosclerotic disease and several methods of quantifying the shape in order to predict the severity of the disease have been described. These methods include pulsatility index, the Laplace transform method, and principal component analysis. This paper describes the development of a system which allows the operator to acquire, display, and store waveforms from each limb and then to quantify the waveforms at the bedside within a few minutes. The system includes a 10 MHz bi-directional Doppler unit, an instantaneous mean frequency processor, and an Apple II microcomputer fitted with an accelerator card. Both the Laplace transform parameters and the pulsatility index are computed and each result is printed in tabular form together with the averaged results of five waveforms from each limb. The printout is suitable for inclusion in the patient's folder. In initial clinical studies Laplace transform analysis exhibited a good correlation with aorto-iliac stenosis as assessed angiographically (R = 0.73 P less than 0.001 t test).

Angiography↗
PubMed1986

Below knee femoropopliteal bypass in severe ischaemia: results using EXS Dacron and human umbilical vein.

This paper reports our preliminary experience using EXS Dacron for infrageniculate femoropopliteal grafts in elderly patients, the majority (78%) suffering critical ischaemia. A comparison is made with human umbilical vein grafts (HUV). Ninety patients (mean age 69 years) with 92 grafts (42 EXS, 50 HUV) were followed up using ultrasound imaging to detect patency (median follow up 26 weeks (range 1-292)). Two and one year cumulative survivals were 57% and 80% for EXS Dacron and 39% and 48% for HUV respectively. Early failure of HUV grafts accounted for most but not all of the difference in survival (P = 0.0012, Wilcoxon Breslow). Graft kinking was not seen in EXS grafts and in only 2 HUV. Poor calf vessel run off was related to early graft occlusion (P = 0.01; Savage, Mantel Cox). This preliminary experience with EXS Dacron is encouraging and suggests the need for a formal randomised study.

Aged↗
PubMed1986

The acute abdomen: management with microcomputer aid.

This paper describes the management consequences of the use of a microcomputer as a special investigation in patients with an acute abdomen. Results in 812 patients seen by 42 junior doctors are compared six monthly and with baseline data from 295 cases from the preceding 2 years. Improvement in diagnostic ability from 48.5% to 71.8% (X2 = 25.8, P less than 0.001) resulted in a fall in negative appendicectomy from 37.5% to 9.71% (X2 = 16.2, P = less than 0.001). Bad management errors were also reduced from 22% to 10% (P = less than 0.01). The number of emergency investigation fell from 4 to 2 and inpatient stay of patients with non-surgical abdominal pain was reduced from 3 to 2 days. These results demonstrate that the use of microcomputers as investigative tools improves the surgical management of patients with acute abdominal pain.

Abdomen, Acute↗
PubMed1985

Staples or sutures for low colorectal anastomoses: a prospective randomized trial.

One hundred and eighteen patients undergoing low colorectal anastomoses were randomly allocated to reconstitution by either single layer interrupted extramucosal sutures or circular staple gun. In the 60 patients undergoing sutured anastomosis there were 2 (3 per cent) clinical leaks and 4 (7 per cent) radiological leaks, and no failures. Of the 58 patients who underwent stapled anastomosis there were 4 failures, 7 (12 per cent) clinical leaks, 14 (24 per cent) radiological leaks and 1 death. Stapled anastomoses were more than ten times as expensive as sutured anastomoses and there were no savings in time or numbers of associated colostomies. An interrupted extramucosal suture technique remains the ultimate standard for low colorectal anastomosis.

Adult↗