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W P Joyce

Publications and source records attributed to W P Joyce.

32 records · Page 2Linked to original sources

Pulse oximetry: a new non-invasive assessment of peripheral arterial occlusive disease.

Peripheral skin perfusion reflects the level of vascularity and viability of a limb and may help in planning the site of amputation or bypass surgery in patients with vascular disease. This study used peripheral pulse oximetry in 20 healthy volunteers and in 20 patients with limb ischaemia. Pulse oximetry saturation levels (Psa,O2) were compared with ankle artery Doppler pressures and transcutaneous oxygen measurements (Ptc,O2). Recordings were taken at two standard sites distally and referenced to finger and forearm to calculate an index. A significant correlation was found between Ptc,O2 and Psa,O2 in patients with ischaemia (r = 0.68, P less than 0.01). A further group of 12 patients with acute limb ischaemia was similarly assessed before and after revascularization. After revascularization mean(s.d.) Ptc,O2 increased from 38(13) to 44(1) mmHg (P greater than 0.05) and mean(s.d.) Psa,O2 increased from 86(3) to 90(4) per cent (P less than 0.01). These data suggest that pulse oximetry is a more sensitive index of peripheral perfusion than Ptc,O2 or ankle artery Doppler pressure and that, because of its accuracy and simplicity, it merits further use.

Angioplasty, Balloon↗

Free radical inhibition and serial chemiluminescence in evolving experimental pancreatitis.

Oxygen free radical activity and inhibition were examined in experimental pancreatitis. Twenty-five rats were randomized to five groups: controls received intravenous saline, to simulate pancreatitis one group received intravenous caerulein (5 micrograms kg-1 h-1), and three groups received sodium taurocholate via the pancreatic duct (0.2 ml, 5 per cent), either alone, following allopurinol or immediately before superoxide dismutase. Chemiluminescence (a phenomenon based on the emission of light during chemical reactions and which is dependent on oxygen free radical activity) was used as an index of oxygen free radical activity and was measured in tissue samples at 5-min intervals following induction of pancreatitis. The control mean(s.e.m.) serum amylase level 1 h after induction of pancreatitis was 635(13) units. It was significantly elevated in caerulein-induced pancreatitis, 1833(118) units (P less than 0.05) and exceeded 3000 units in all taurocholate-infused animals. Mean(s.e.m.) chemiluminescence ranged from 44 (8) mV 100 mg-1 at time zero to 404(113) mV 100 mg-1 at 1 h in controls. In caerulein-induced pancreatitis mean(s.e.m.) chemiluminescence peaked at 20 min (1399(239) mV 100 mg-1, P less than 0.02) and in taurocholate-induced pancreatitis at 15 min (2316(95) mV 100 mg-1, P less than 0.004). Superoxide dismutase significantly reduced chemiluminescence and hyperamylasaemia in taurocholate groups. Increasing oxygen free radical activity paralleled evolving pancreatitis. Superoxide dismutase may have a therapeutic role in pancreatitis.

Allopurinol↗

Supraceliac clamping: an underused alternative in aortic surgery.

In the majority of patients undergoing abdominal aortic surgery, proximal clamping can be readily achieved below the renal vessels. In some situations however, this may be difficult, impossible or ill advised, and an alternative method of control must be sought. We describe the technique and report our personal experience with supraceliac clamping, a maneuver which merits more widespread use in emergency and difficult infrarenal aortic surgery.

Aorta, Abdominal↗

Small bowel complications of metastatic lung carcinoma.

A case of small bowel perforation and a case of small bowel obstruction as a result of metastatic lung carcinoma are presented. The surgical management of each is discussed. The patient who presented with small bowel perforation died in the immediate post-operative period, while the patient who presented with small bowel obstruction is alive and well six months later. Patients with primary lung carcinoma who present with an acute abdomen should be treated by standard surgical principles irrespective of their primary pathology.

Aged↗

The role of central haemodynamic monitoring in abdominal aortic surgery. A prospective randomised study.

To test the hypothesis that central haemodynamic monitoring is not necessary in all patients undergoing abdominal aortic surgery, a prospective randomised study in 40 consecutive patients undergoing elective abdominal aortic surgery was carried out. Patients with unstable angina, recent myocardial infarction (less than or equal to 6 months), and left ventricular ejection fraction (LVEF) less than 0.50 were excluded. Twenty-one patients had perioperative central haemodynamic monitoring while 19 patients had central venous pressure monitoring alone. Parameters studied included, perioperative haemodynamics and fluid balance, perioperative cardiac drug administration, operation time and clamp time, postoperative renal function, incidence of postoperative ventilation and line complications, duration of hospital and ICU stay, and 30 day postoperative outcome. Results obtained were compared with a high risk group of patients (LVEF less than 0.50) undergoing similar surgery. Statistical analysis failed to show any difference in outcome for any variable measured in either low risk group. All serious postoperative cardiac complications occurred in patients with LVEF less than 0.50 (P less than 0.0001). These data suggest that patients with LVEF greater than or equal to 0.50 are at low risk of developing postoperative cardiac complications and can be successfully managed perioperatively without the added potential risks and costs of central haemodynamic monitoring.

Aged↗

The influence of central haemodynamics on transcutaneous oxygen (TcpO2) measurements.

Transcutaneous oxygen measurements (TcpO2) have been shown to be an index of tissue perfusion and it has been suggested that the main haemodynamic variable influencing tissue perfusion is cardiac output, assuming that inspired oxygen remains constant. To investigate this hypothesis we studied 23 consecutive patients in order to identify if changes in cardiac output correlated with similar changes in TcpO2 measurements. No correlation was found to suggest that cardiac output was the main haemodynamic determinant of TcpO2 measurements.

Adult↗

Failure of bicycle exercise electrocardiograms to predict major post-operative cardiac complications in patients undergoing abdominal aortic surgery.

To determine if exercise electrocardiograms (EECGs) are justified in routine pre-operative screening for cardiac disease, we performed a prospective study on 77 consecutive patients scheduled for infrarenal aortic reconstructive surgery. All patients had EECGs performed 1-12 days prior to elective surgery. In addition to routine clinical assessment of cardiac disease, all patients were allocated a Goldman risk score. Four patients developed major post-operative cardiac complications of whom one patient died. EECG was not a significant predictor of outcome, as 48.6% of all EECGs were inadequate due to non-completion of the exercise protocol. Significant pre-operative predictors of outcome were a history of angina (p less than 0.01), myocardial infarction (p less than 0.001), congestive cardiac failure (p less than 0.0001), or a Goldman score of greater than 14 (p less than 0.05). By multivariate analysis of the pre-operative risk factors a history of congestive cardiac failure was found to be the most significant independent predictor of post-operative cardiac complications.

Adult↗

Advanced trauma and life support principles: an audit of their application in a rural trauma centre.

In December of 1995 a system of trauma care based on Advanced Trauma Life Support (ATLS) principles was instituted to assess the impact of such principles on trauma care in a rural general hospital setting. This audit reviews the results over a 2 yr period to December 1997. All patients admitted with major trauma (i.e. with life threatening or potentially life threatening injuries) to Cavan General Hospital (CGH) were eligible for inclusion. This numbered 70 patients admitted (for at least 3 days), or who were transferred after resuscitation and stabilization as well as inpatient deaths. Twenty-seven patients who died prior to admission are also reviewed. The endpoints assessed were death, disability and survival 3 months post-accident. Based on injury severity scores 7 per cent of cases suffered fatal non-survivable injury, 20-30 per cent had very serious injury with an overall mortality rate of 17 per cent. The predicted mortality rate was 30 per cent. One-third had their full treatment at CGH with a 76 per cent survival rate. The other two-thirds were transferred for specialist intervention with an overall survival of 80 per cent, a disability rate of 16 per cent and a mortality rate of 4 per cent. No patient died during transportation.

Adolescent↗

Feasibility of day case varicose vein surgery in a district general hospital.

BACKGROUND: Day case surgery may reduce inpatient bed requirements, and varicose surgery may be an ideal operation to test the functioning of a day surgery service. AIMS: To evaluate retrospectively the feasibility of day case varicose vein surgery in all-comers, and to identify the risk factors for admission. METHODS: Over a three-year period from July 1995 to July 1998, all patients requiring varicose vein surgery had their procedure performed as a day case. A standard technique of sapheno-femoral ligation with below-knee stripping of the long saphenous vein and multiple stab avulsions of varicosities was performed. All limbs were dressed with wool in crepe bandage and were reviewed post-operatively at six weeks. RESULTS: Five hundred and forty two patients underwent varicose vein surgery, of whom 26% had bilateral varicose veins, 88% had primary varicose veins and 22% had recurrent disease. The procedure was performed under general anaesthesia in 86% of cases and under spinal anaesthesia in the rest. There was no peri-operative mortality. Ten patients (1.9%) developed post-operative complications. Seventy two per cent of patients were discharged on the day of surgery, a further 25% required admission for one night due to minor anaesthetic complications and patient preference. Four per cent required admission for more than 24 hours. The need for overnight admission was associated with the age of the patients (p < 0.0001), bilateral varicose vein surgery (p < 0.005) and the use of spinal anaesthesia (p < 0.01). CONCLUSION: Although varicose vein surgery is safe, acceptable and cost-effective as a day case procedure, if attempted in all-comers, overnight admission will be required in a significant proportion. Pre-operative selection is advised.

Ambulatory Surgical Procedures↗