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A J McCleary

Publications and source records attributed to A J McCleary.

12 recordsLinked to original sources
PubMed2003

Pelviureteric junction disruption as a complication of chemical lumbar sympathectomy.

Chemical lumbar sympathectomy is a commonly performed procedure in vascular surgery and pain management. This case report discusses the management of a patient who suffered pelviureteric junction disruption following phenol injection for ischaemic leg pain despite radiological evidence of correct placement. The authors suspect this is an underreported complication, which could be relevant in obtaining informed consent.

Humans↗
PubMed2001

Vascular surgeon's experience with intraoperative angioplasty.

BACKGROUND: Intraoperative balloon angioplasty as an adjunct to vascular reconstruction is controversial and radiologists suggest that it may be less effective than preoperative or postoperative percutaneous transluminal angioplasty. The aim of the present study was to explore the role of intraoperative balloon angioplasty as performed by a vascular surgeon. METHODS: The notes and angiograms of 63 patients on whom 67 intraoperative angioplasty/stenting procedures were performed were retrieved using a computerized prospective audit system. RESULTS: Although 41 procedures were planned preoperatively, 26 (39%) followed intraoperative angiography. Twenty-seven were performed to improve inflow for distal reconstructions and 27 were performed to improve outflow for proximal reconstructions. Thirteen (anastomotic stenoses) followed synthetic graft thrombectomy. Twenty-seven iliac, 15 superficial femoral artery (SFA), 11 popliteal, one anterior tibial and 13 anastomotic lesions were dilated and there were four technical failures. At follow up (median: 24 months; 3-monthly duplex scan, ankle brachial pressure indices) primary patency rates by lifetable analysis were: iliac, 75%; SFA, 91%; popliteal, 82%; anastomotic, 8%. CONCLUSIONS: There are situations in which intraoperative angioplasty would be advantageous and can be performed successfully by a surgeon. Because a significant proportion of procedures was unplanned and a vascular radiologist was not readily available the authors conclude that vascular surgical trainees should be trained in angioplasty techniques. However, balloon angioplasty is ineffective in treating anastomotic stenoses and surgical intervention is required for these lesions.

Adult↗
PubMed2001

Closing the loop: the role of audit in reducing groin complications associated with coronary angiography.

BACKGROUND: Local vascular complications of coronary angiography present a significant but often ignored clinical problem. This audit was performed because of a perception that the number of false aneurysms requiring surgical repair was increasing. STANDARD: An acceptable incidence of false aneurysm was derived from series in which ultrasound examinations were only performed if a false aneurysm was suspected (0.06-0.7%). The success rate of ultrasound (US) directed compression ranged from 50% to 93%. ASSESSMENT OF LOCAL PRACTICE: Data were retrieved from cardiology, radiology and vascular surgery databases in addition to case note review. The incidence of false aneurysm was significantly higher than that of historical control groups from the authors' institution (1.5% vs 0.5%, P < 0.05) and in published series used as the standard. The success rate of US directed compression was also poor compared to historical controls (25% vs 55%,P < 0.05) and previously published series. IMPLEMENTATION OF CHANGE: Recommended changes included the use of fluoroscopy to identify the femoral head to avoid low puncture, strict adherence to the existing protocol for sheath removal and the use of adequate analgesia and sedation prior to attempted US compression. REASSESSMENT OF LOCAL PRACTICE: The incidence of false aneurysm fell to that of the standard set by previous studies. US directed compression was successful in 100%. CONCLUSIONS: The audit was successful in that the incidence of false aneurysm fell and the success rate of US directed compression increased, but the specific reasons for the improvements remain unclear.

Aneurysm, False↗
PubMed2001

Carotid endarterectomy; local or general anaesthesia?

OBJECTIVES: to review the evidence for theoretical and clinical benefits of local or general anaesthesia for carotid endarterectomy. METHODS: literature review. RESULTS: animal studies suggest cerebral protection by a variety of general anaesthetic agents but clinical evidence is lacking. There is some clinical evidence that normal cerebral protective reflexes are preserved with local anaesthesia. Shunt insertion is the most widely used method of providing cerebral protection with awake testing the most reliable monitoring technique for the identification of ischaemia. There are therefore theoretical arguments for a reduced risk of perioperative stroke when local anaesthesia is used and this is supported by a meta-analysis of non-randomised studies. Intraoperative blood pressure is always higher with local anaesthesia but the incidence of postoperative haemodynamic instability seems to be independent of anaesthetic technique. There is little evidence that myocardial ischaemia is more common with either anaesthetic technique but meta-analysis of non-randomised again suggests fewer cardiac complications with local anaesthesia. Cranial nerve injury and haematoma formation may be less common with local anaesthesia but the evidence is weak. There is no evidence that surgery is more difficult with local anaesthesia or that it is poorly tolerated by the patients. CONCLUSIONS: there are theoretical arguments and clinical evidence that the outcome from carotid endarterectomy may be better when local anaesthesia is used with no significant disadvantages. An appropriately designed randomised trial is required to confirm this.

Anesthesia, General↗
PubMed1999

Does hypothermia prevent cerebral ischaemia during cardiopulmonary bypass?

It is believed that moderate hypothermia (25-32 degrees C) during cardiopulmonary bypass provides cerebral protection by reducing the cerebral metabolic rate (CMRO2). Nevertheless episodes of ischaemia do occur and thus it has been suggested that cerebral oxygenation should be monitored by jugular venous oximetry. However, this technique is cumbersome and invasive. Near infrared spectroscopy (NIRS) provides a non-invasive assessment of cerebral oxygenation and this was used together with continuousjugular venous oximetry in 21 patients undergoing hypothermic cardiopulmonary bypass. During the hypothermic period, jugular venous oximetry indicated reduced oxygen extraction consistent with a reduction in CMRO2 (increase from 61 +/- 2.5% to 74 +/- 2.5%). In contrast, near infrared spectroscopy demonstrated increased oxygen extraction (HbO2 - 11.5 +/- 1 microM, HHb + 3.2 +/- 0.3 microM) and a fall in the cerebral concentration of oxidized cytochrome oxidase ( - 1.7 +/- 0.3 microM) indicating ischaemia. These results suggest that cerebral ischaemia occurs during hypothermic cardiopulmonary bypass with a spurious rise in jugular venous oxygen saturation, which represents arterio-venous shunting. Thus if hypothermia does facilitate cerebral protection it does not appear to be a direct result of a reduction in CMRO2 and oxygen requirement.

Adult↗
PubMed1998

Cerebral haemodynamics and embolization during carotid angioplasty in high-risk patients.

BACKGROUND: Patients with symptomatic internal carotid artery (ICA) stenosis greater than 70 per cent in association with a contralateral ICA occlusion may have an increased risk of stroke following carotid endarterectomy. Such patients might benefit from the theoretically shorter ischaemic time offered by carotid angioplasty and stenting. METHODS: Nine patients who underwent carotid angioplasty and stenting were monitored using near-infrared spectroscopy, continuous jugular venous oximetry and transcranial Doppler ultrasonography to detect both haemodynamic ischaemia and embolic events. RESULTS: Significant ischaemia occurred in four of the nine patients once the stenosis had been crossed by the guidewire (spectroscopy and oximetry). Inflation of the angioplasty balloon resulted in a brief period of ischaemia and showers of emboli in all patients (ultrasonography) and this persisted for more than 3 min after balloon deflation in three patients. One patient had a major disabling stroke due to ICA thrombosis. CONCLUSION: Angioplasty and stenting in these high-risk patients may not confer any advantage over conventional surgery in terms of both haemodynamic ischaemia and embolization.

Aged↗
PubMed1996

The differing effects of regional and general anaesthesia on cerebral metabolism during carotid endarterectomy.

OBJECTIVES: To examine the effects of either regional (RA) or general (GA) anaesthesia upon parameters of cerebral metabolism (near infrared spectroscopy, continuous jugular venous oximetry) during carotid endarterectomy. DESIGN: Prospective, non-randomised, observational study. MATERIALS: Sixty-five consecutive patients (33 RA; 32 GA) undergoing carotid endarterectomy. METHODS: (i) Near infrared spectroscopy: measurement of concentrations of cerebral oxyhaemoglobin (HbO2), deoxyhaemoglobin (HHb) and oxidised cytochrome oxidase (caa3). (ii) Continuous jugular venous oximetry: O2 saturation of jugular venous blood (SJvO2). (iii) Stump pressure in internal carotid artery. RESULTS: A reduction in SJvO2 (RA: 13% (95% CI-3 to 29%) GA: 9% (95% CI-2 to 20%), p < 0.08) and a fall in caa3 levels (RA vs. GA: 25/31 vs. 19/31, p = 0.2) was more likely in patients given a RA following application of the carotid clamps. When HbO2 and caa3 did fall however spontaneous recovery occurred more often (RA vs. GA; caa3: 18/25 vs. 5/19, p < 0.005; HbO2: 30/31 vs. 4/28, p < 0.001). CONCLUSIONS: Although GA may offer a degree of cerebral protection by reducing cerebral metabolic rate (lower falls in SJvO2 and caa3) RA preserved cerebral autoregulation as judged by the spontaneous recovery in caa3 and HbO2 levels.

Aged↗