J.I. Spark

Percutaneous transluminal angioplasty for intermittent claudication: Evidence on which to base the medicine

OBJECTIVESnThis study aims to assess the impact of PTA on the quality of life (QoL) of claudicants and to analyse which patients and which arterial lesions derive the most benefit.nnnDESIGNnA prospective observational study.nnnMATERIALSnOne hundred and seventeen claudicants undergoing PTA were studied; 35 patients had bilateral disease, whilst 82 had unilateral disease and underwent PTA to a solitary iliac lesion, solitary superficial femoral or a iliac lesion above a diseased superficial femoral artery in 24, 39 and 19 cases, respectively.nnnMETHODSnPatients completed the Short Form 36 (SF36) and EuroQol (EQ) QoL assessment instruments prior to and at 1, 3, 6, and 12 months following intervention. The SF36 produces a QoL profile, whilst the EQ produces two QoL indices.nnnRESULTSnClaudication has a deleterious effect on QoL, especially in patients with multi-segment disease. PTA results in an immediate and lasting improvement in the QoL of claudicants. Unilateral claudicants undergoing PTA to a solitary iliac lesion demonstrate the most marked QoL benefits and 12 months post PTA report a QoL approaching that of an age-matched population. Patients with bilateral claudication undergoing unilateral PTA and unilateral claudicants undergoing PTA to a solitary SFA lesion demonstrate some QoL benefits, but at 12 months post PTA do not approach the QoL scores of an age-matched population. Unilateral claudicants undergoing iliac PTA above a diseased SFA demonstrate minimal QoL changes.nnnCONCLUSIONSnThese results should influence decision making in the management of claudication and it may be possible to prioritise PTA waiting lists to ensure patients with greatest potential benefit are treated with most urgency.

Randomized clinical trial of intraoperative autotransfusion in surgery for abdominal aortic aneurysm.

Perioperative homologous blood transfusion (HBT) is associated with adverse reactions and risks transmission of infection. It has also been implicated as an immunosuppressive agent. Intraoperative autotransfusion (IAT) is a potential method of autologous transfusion.

ALLOGENEIC VERSUS AUTOLOGOUS BLOOD DURING ABDOMINAL AORTIC ANEURYSM SURGERY

OBJECTIVESnTo determine if cell-salvaged autologous blood can serve as an alternative to homologous blood, and to examine the incidence of infected complications and length of postoperative stay.nnnDESIGNnA prospective randomised study comprising autologous and homologous blood transfusions in patients undergoing elective infrarenal abdominal aortic surgery.nnnMETHODSnFifty patients undergoing AAA surgery were prospectively randomised to homologous blood (n = 27), or autologous blood transfusion (n = 23), using a cell salvage autotransfusion device.nnnRESULTSnThe haemoglobin at the time of hospital discharge was similar for both groups (11.0 vs. 10.8 g/dl) with no difference in perioperative mortality. The length of stay was reduced in those patients who received autologous blood (9 days vs. 12 days, p < 0.05 Mann-Whitney U test). There were four infected cases in the autologous group and 12 in the homologous group (p = n.s., Fishers exact probability test). However, patients who received 3-4 units of homologous blood had an increased risk of infection compared to those who received a similar amount of autologous blood (50% vs. 0%).nnnCONCLUSIONSnCell salvage autologous blood can safely replace, or at least decrease, exposure to homologous blood transfusion, with a reduction in the mean hospital stay.

Exercise-induced Neutrophil Activation in Claudicants: a Physiological or Pathological Response to Exhaustive Exercise?

OBJECTIVESnTo assess the effect of exhaustive exercise on neutrophil activation and degranulation in claudicants and controls. We investigated the hypothesis that neutrophil activation and degranulation are normal responses to exhaustive exercise in healthy patients.nnnDESIGNnThis was a controlled experimental two-group study.nnnMATERIALSnExercise was performed using a fixed workload treadmill test. Neutrophil activation was assessed by flow cytometry of whole blood labelled with anti-CD11b mouse IgG, and neutrophil degranulation in terms of plasma elastase measured by enzyme-linked immunosorbent assay.nnnMETHODSnTwenty-eight claudicants with stage 1 chronic leg ischaemia, and 22 healthy controls were recruited. Blood and urine samples were collected before and after treadmill exercise. Claudicants exercised to their maximum walking distance, and controls at a higher fatigue workload for a maximum of 20 min.nnnRESULTSnExercise produced a brief but significant neutrophilia in both groups. Neutrophil CD11b expression increased significantly after exercise only in the claudicants, and was associated with a significant rise in plasma neutrophil elastase. These indices remained unchanged in the control group at all time points despite exercise at a fatigue level.nnnCONCLUSIONnThe inflammatory response associated with exercise in claudicants is not simply a physiological response to exhaustive exercise.

The regulation of neutrophil activation and adhesion during femorodistal bypass surgery

OBJECTIVEnTo determine the effect that revascularising chronic critically ischaemic legs has no neutrophil activation and adhesion.nnnDESIGNnProspective clinical study.nnnSETTINGnUniversity Hospital.nnnMATERIALSnTwenty-five patients, 16 men and nine women undergoing femorodistal surgery.nnnCHIEF OUTCOME MEASURESnVenous blood assays for neutrophils expression of CD11b, neutrophil adhesion, and the plasma concentration of the shed endothelial adhesion receptor, soluble intracellular adhesion molecule 1 (sICAM-1). Urinary microalbuminaemia was measured and expressed as an albumin/creatinine ratio (ACR), as a marker of vascular permeability and plasma neutrophil elastase as evidence of neutrophil activation. Venous blood was taken preoperatively, during surgery and for the first 7 days postoperatively.nnnMAIN RESULTSnNeutrophil CD11b expression fell following reperfusion of the limb (21.4 mcf to 9.7 mcf, p < 0.02 Mann Whitney U-test) as did neutrophil adhesion (preop. 75% adhesion, postop. 28% p < 0.01). However, the plasma elastase levels rose from 95 micrograms/l to 345 micrograms/l at 4 h and the ACR increased from 5.3 mg/ml to 304.2 mg/ml. The concentration of sICAM-1 fell following reperfusion (p < 0.04).nnnCONCLUSIONnThe change in CD11b, sICAM-1 and adhesion may represent a normal immunological response to ischaemia/reperfusion.

How effective is acute normovolaemic haemodilution in femoro-distal bypass surgery?

BACKGROUNDnRecent guidelines have emphasised the use of autologous blood in the surgical setting. The aim of this study was to analyse the efficacy and efficiency of acute normovolaemic haemodilution (ANH) as a blood conservation intervention in patients undergoing elective femoro-distal surgery for critical limb ischaemia.nnnMETHODSnForty patients were studied prospectively. The volume of the blood collected was derived as follows: Blood volume removed = patients blood volume (initial haematocrit - final haematocrit/average haematocrit) where final haematocrit is 30% and patients blood volume is 70 and 65 ml/kg for a man and a woman, respectively.nnnRESULTSnTwenty-five patients were suitable for ANH and 15 patients were excluded because of poor ventricular function, anaemia or renal disease. Nine of the 25 patients (44%) had <500ml of surgical blood loss and would have avoided homologous blood transfusion (HBT). Four of the patients lost >2000ml of blood and could not avoid HBT through ANH. Twelve patients had moderate blood loss (950-1400 ml), with eight of these patients requiring transfusion. Four patients avoided exposure to homologous blood.nnnCONCLUSIONnANH is in evolution and as a single blood conservation intervention, contributes only modestly to blood conservation.