[Arterial thrombolysis in peripheral arterial occlusions--where are the limits of the realm and what are the responsibilities of a vascular surgeon?]

Arterial thrombolysis is a well established treatment for acute myocardial ischaemia, with respectable results. It is gaining ground in peripheral vascular surgery as well, particularly in the treatment of acute ischaemia due to occlusion of a sclerotic artery or an arterial graft. However, in case of myocardial ischaemia diagnosis (coronary angiogram), treatment (thrombolysis, PTCA or revascularisation) and recognition for the need for acute surgical treatment are in the same hands in cardiology, in case of peripheral arterial occlusions diagnostics (and therapy in some extent) are provided by radiologists, while patients are usually referred to vascular surgeons. They can provide limited diagnostics (intraoperative angiogram) and can treat patients by non-surgical means (i.e. intraoperative thrombolysis). Although co-operation between radiology and vascular surgical services is crucial and can save limbs and lives, in everyday practice we frequently have to decide whether the ischaemic limb can be treated by thrombolysis only (carried out by radiologists) or the extent and stage of ischaemia are such that they require the faster surgical reconstruction, often completed with intraoperative angiogram and thrombolysis. Whose decision should it be? Should vascular surgeons force thrombolysis, should they do it themselves? What are the cost implications of the successful and unsuccessful thrombolysis?

Training in infrainguinal bypass surgery for severe leg ischaemia

BACKGROUND

Recent changes in surgical training in the UK mean that operative experience must be gained more efficiently. However, it is important to demonstrate that improved training opportunities are not associated with inferior patient outcomes. The aim was to examine changes in training in infrainguinal bypass surgery and to compare the outcomes of operations performed by consultants and trainees.

METHODS

A prospectively gathered, computerized database of 1077 consecutive infrainguinal bypasses performed on 1003 patients for chronic severe leg ischaemia between 1 January 1983 and 31 December 1998 was analysed.

RESULTS

Consultants performed 733 (68 per cent) infrainguinal bypasses to the following distal sites: 347 (47 per cent) above-knee popliteal artery, 257 (35 per cent) below-knee popliteal artery, 121 (17 per cent) to a crural artery and eight (1 per cent) other. Trainees performed 344 operations: 170 (49 per cent) were to the above-knee popliteal artery, 122 (35 per cent) to the below-knee popliteal artery, 48 (14 per cent) crural and four (1 per cent) other. The operative mortality rate was 27 (4 per cent) of 733 for consultants and 11 (3 per cent) of 344 for trainees (P > 0.05, chi2 test). There were no significant differences in patency or limb salvage at 36 months after operation between consultants and trainees, regardless of the site of distal anastomosis and the type of conduit used.

CONCLUSION

With appropriate case selection and supervision, training in infrainguinal bypass grafting does not compromise early or long-term patient outcomes.

[Treatment of critical lower limb ischemia--where are we standing at the turn of the Millennium?]

The treatment of chronic critical limb ischaemia (CLI) is a very important and constantly developing field of vascular surgery. The high incidence of CLI (50-100/100,000 inhabitants [10]) means that vascular surgeons at a district general hospital/county hospital, providing care for 250-300,000 people, see about 120-150 cases in a year, 70-75% of them needing elective or acute intervention. We have witnessed many important changes over the last 1-2 decades in the management of this substantial field of vascular surgery. The in situ technique, angioscopically assisted valvulotomy, venous cuffs and A-V fistulae at the distal anastomosis of an infrainguinal bypass, the intraluminal and subintimal angioplasty-technique in hand, graft-surveillance programmes and the more aggressive treatment of graft-infection all provide a potentially better chance for limb salvage. Do we follow the trends and seize them?

[Adult respiratory distress syndrome after open heart surgery]

Cardiopulmonary bypass used in open heart surgery is responsible for nearly 15% of adult respiratory distress syndrome. The condition has a high mortality rate and still today we do not have a specific therapy for it. The aim of this study was to reveal the factors that are responsible for the adult respiratory distress syndrome developing after open heart operations. A retrospective statistical analysis of the database of 837 consecutive open heart operations was performed. Those patients in whom the adult respiratory distress syndrome has not developed have served as control group. chi 2 probe, Student t test and the Mann-Whitney test were used for the analysis. The authors applied logistic regression analysis for the multivariate investigation. Adult respiratory distress syndrome has developed in 10 patients (1.2%) in the postoperative period. One patient in whom the adult respiratory distress syndrome was accompanied by multiorgan failure has been lost. Between the two subgroups the authors found significant difference in the amount of blood and fresh frozen plasma transfusion, in the duration of ischaemic period and cardiopulmonary bypass, in anaesthesia time, and also in the occurrence of postoperative low cardiac output syndrome and acute myocardial infarction. Fresh frozen plasma can be a risk factor in the development of postoperative adult respiratory distress syndrome. In order to avoid the occurrence of this syndrome a great emphasis must be put on the pulmonary prevention.

Gauze swabs left intrapericardially following cardiac surgery

The occurrence of surgical gauze swabs left in the body following operations is not as rare as one would suspect, however the actual incidence is difficult to estimate. This accident seems to be occurring most frequently in general and gastro-intestinal surgery followed by operations in gynaecology and obstetrics and orthopaedics. There have been only a few papers in the literature dealing with the topic of foreign bodies left in place after cardiac surgical procedures. In this paper two cases of gauze swabs left intrapericardially following cardiac surgery are presented. The issue goes far beyond professional significance alone, but raises important and critical questions of medical ethics let alone legal implications.

Early proarrhythmia during intravenous amiodarone treatment

We present a case of early (within the first 24 hours) development of malignant torsades de pointes (TdP) associated with intravenous amiodarone therapy. After correction of predisposing factors (heart failure, hypokalemia, digoxin) amiodarone again resulted in torsades. This observation suggests that in patients who have experienced amiodarone-induced proarrhythmia, amiodarone administration under different, more stable clinical conditions may still be hazardous.

Instructional set and physiological response to CO2 inhalation

OBJECTIVE

Previous studies have suggested that manipulations in patient instructions before inhalation of carbon dioxide (CO2) may blunt its anxiogenic effects. The authors examined the effects of a range of instructional types on panic rates and physiological responses to CO2 inhalation.

METHOD

Thirty-seven patients with panic disorder and 16 normal subjects were exposed to CO2 inhalation under one of three instructional conditions: 1) reassurance (reiterated safety assurances), 2) control dial (patients were instructed on using an operative dial to reduce the concentration of CO2 in the breathing canopy), and 3) basic instructions (standard information). Perceived breathlessness was measured with the Borg Scale of Respiratory Exertion.

RESULTS

Manipulation of instructional sets did not affect panic rates among patients. The reassurance condition, however, produced a significant reduction in perceived breathlessness.

CONCLUSIONS

CO2-induced panic is a robust biological effect that occurs independent of cognitive set changes, such as illusion of control or reassurance of safety. Conclusions drawn from this study are bolstered by the fact that it is methodologically rigorous: it had a large number of subjects, used random assignment to one of three instructions, included a full array of both subjective and biological measures, and included independent ratings.

[Low cardiac output following open heart surgery and catecholamine therapy]

The authors have studied the possible risk factors and complications of low cardiac output (LCO) following open heart operations. A retrospective analysis of 537 consecutive open heart operations has been performed with regards to the patients past medical and perioperative data. For statistical analysis the authors have applied the Chi-square test, T-probe, Mann-Whitney-test and logistical regression analysis by means of the SPSS software. Occurrence of various types of operations was as follows: coronary bypass (CABG): n = 266, 49.5%, combined CABG: n = 62, 11.5%, aortic valve replacement (AVR): n = 73, 13.6%, mitral valve replacement (MVR): n = 59, 11%, multiple valve replacement: n = 39, 7.3%, adult congenital surgery: n = 25, 4.7%. Aortic dissection repair: n = 6, 1.1%, miscellaneous: n = 7, 1.3%. LCO has developed in 7.3% (n = 39) of the patients. The authors have concluded that in the studied group of patients the independent risk factors of postoperative LCO are as follows: atrial fibrillation in the patient history, mitral valve disease, perioperative myocardial infarction, length of anaesthesia, NYHA stage, number of transfused units of blood, and the perioperative LDH value. Beyond these variables the cause of LCO in some cases was surely an intra or perioperative myocardial necrosis. At least a certain part of this perioperative myocardial damage must have been or might have been caused by the catecholamines given under compulsion for the treatment of LCO.

Effect of the different factors on the iontophoretic delivery of calcium ions from bentonite

The calcium content of mud patches used for therapy is very small. Several mineral clays originating from Hungary served as a base material for experiments in order to find a suitable drug for transdermal introduction of calcium ions into the body. The Ca++ transport through the pig skin has been investigated in vitro in diffusion cells applying iontophoresis. Studies of electrical and physicochemical factors acting on the permeation kinetics of in vitro experiments were performed. The utilization of direct current has intensified the Ca++ transport through the pig skin (129.78+/-26. 15 microgram Ca/cm2). On using pulsate currents the amount of the Ca++ penetrating through the skin was 5-10 times higher (283.18+/-16.89 microgram Ca/cm2, 388.71+/-19.90 microgram Ca/cm2) than that of the passive transport (36.22+/-14.20 microgram Ca/cm2). The amount of Ca++ cumulated in the receptor compartment was directly proportional to the amount of bentonite (a natural mineral clay with a large cation exchange capacity) in the donor compartment and to the concentration of Ca++ in the lattice of the applied mineral clay. Therefore, the experiments were carried out on a bentonite previously enriched in Ca++ in its lattice (50 mg Ca/g bentonite). The results of the in vitro studies could open a new field of application in the therapy of osteoporosis or in the use of mineral substances.

Ultrasonographic findings of renal dysplasia in cocker spaniels: eight cases

A retrospective study of eight young Cocker Spaniels aged 9-24 months was performed to describe the ultrasonographic findings of histologically confirmed renal dysplasia. Ultrasonography revealed kidneys of significantly (p < 0.001) reduced volume in all dogs. During qualitative evaluation, two different types of sonographic alterations could be seen. In one type of the ultrasound alterations, corticomedullary demarcation was distinct and the renal cortex was remarkably thin, which was best seen in the dorsal (frontal) imaging plane. In the other type of the ultrasound appearance, overall increased echogenicity with poor corticomedullary demarcation was noticed, and the kidneys could hardly be separated from their surroundings. These features were best recognised in the sagittal (coronal) imaging plane. In one dog with secondary hypercalcaemia, a hyperechoic corticomedullary area was also seen. Post-mortem histological diagnosis revealed renal dysplasia and secondary fibrosis. Based on ultrasound findings alone, renal dysplasia (renal familial disease) can be suspected when small kidneys with thin echogenic cortex are present in young dogs. An ultrasound image, similar to that of fibrotic kidneys (increased overall echogenicity and reduced corticomedullary definition) cannot be differentiated from chronic inflammatory disease and from end-stage kidneys. Therefore, ultrasound-guided biopsy or post-mortem histology is necessary for the definitive diagnosis of renal dysplasia. This is the first study reporting on the ultrasound appearance of renal dysplasia in Cocker Spaniel dogs.

Infrared imaging of human brain sections. A new biomedical application of the thermocamera

Human brains, removed at routine autopsy, were subjected to neuropathological investigation. The usual gross morphological investigation of the brains was extended to include the detection of their infrared emissions. Fundamental structures, such as the grey and the white matter, were separated on the infrared images. Furthermore, pathological processes, such as ischaemic damage, haemorrhage, and sclerotic plaques, hardly seen on the normal photographs, gave a strong signal on the infrared pictures. These pilot experiments demonstrated that infrared detection is a reproducible method in this type of biomedical application, and potentially a very useful tool in macroscopic pathology.

A new combined electrothermal-hollow cathode atom and emission source

A new radiation source based on the FANES-method has been developed in order to achieve an intensity enhancement of the radiation produced. Investigations carried out with this new source are controlled by a computer system connected with a multichannel spectrometer having a wavelength modulated background corrector. First results show that the combination of the two sources increases the emission intensity of spectral lines.

[Simultaneous heart valve implantation and coronary bypass following kidney transplantation]

The authors report simultaneous aortic valve replacement and coronary artery bypass grafting surgery successfully performed in a patient with functioning transplanted kidney. The patient's cardiac status was classified as NYHA class III. The indication of the cardiac operation was a heavily calcified, stenotic and insufficient aortic valve and severe coronary artery disease. Renal function and blood biochemistry tests did not show significant changes in the postoperative period. The patient was discharged on the 15. postoperative day after an uneventful postoperative period. He remained asymptotic for two and a half years after operation. His cardiac status judged by postoperative treadmill stress was NYHA class I. The outcome of this case in accordance with results found in the literature further confirms that, if the clinical indications are appropriate, a kidney transplant patient can survive and benefit from cardiac surgery. To our knowledge our patient has been the only one who has survived aortic valve replacement and double coronary artery bypass grafting after kidney transplantation, and this is the first case that has ever been reported in Hungary.

Uncoupling of the noradrenergic-hypothalamic-pituitary-adrenal axis in panic disorder patients

In this paper the authors examine the interrelationship of both the noradrenergic (NA) system and the hypothalamic-pituitary-adrenal (HPA) axis and its implications for panic disorder (PD). Seventeen PD patients and 16 healthy volunteers were challenged orally 12 weeks apart with the alpha 2-agonist clonidine (13 healthy volunteers and 12 patients repeated the challenge). Between challenges, PD patients were treated with fluoxetine, with 10 of 12 improving at least moderately. Both during the acute phase of the illness and during the phase of pharmacological improvement, patients demonstrated a greater percentage of reductions of plasma 3-methoxy-4-hydroxyphenylglycol (MHPG) and plasma cortisol during clonidine challenge. We used correlational matrices to examine the relationship between the NA system, as reflected by plasma MHPG, and the HPA axis, as reflected by plasma cortisol measures. Healthy volunteers exhibited multiple significant "couplings" between either baseline or maximal decrease (delta max) of plasma MHPG, with either baseline or delta max plasma cortisol measures both within the first and second challenges and between the first and second challenges. In contrast, PD patients demonstrated "uncoupling" of the NA system and the HPA axis, with no significant correlations observed between either baseline and/or maximal decrease (delta max) measures of MHPG with the same cortisol measures for either the first or second challenge. The same uncoupling was observed for NA/HPA correlations between the first and second challenges. These data suggest that the hyperresponsivity to clonidine in PD patients persists during fluoxetine treatment.(ABSTRACT TRUNCATED AT 250 WORDS)