Esmarch Bandage Research Articles

Tourniquet-induced nerve ischemia: an experimental investigation.

This experimental investigation has demonstrated that an inflated pneumatic tourniquet causes slowing in conduction velocity of the sicatic nerve. The amount of slowing and recovery time vary according to inflation pressure and to the duration of applied pressure. The conduction velocity always returned to normal provided the tourniquet was inflated for 2 hours or less, and pressures were below 500 mm Hg. The nerve directly under the tourniquet was most susceptible to injury. Inflation pressure should be as low as possible and be determined according to systolic blood pressure. An Esmarch bandage should not be used as a pneumatic tourniquet because of its very small surface area. The cause of the nerve injury demonstrated is likely related to arterial ischemia.

Prolonged conduction block with axonal degeneration. An electrophysiological study.

Serial electrophysiological studies were performed in a case of 'tourniquet paralysis' of the upper limb after the application of an Esmarch bandage above the elbow. Three months after onset of paralysis, nerve conduction was reduced to a quarter of normal between elbow and and axilla along the few fibres still conducting through the lesion, but was normal distal to the block. Seven months after nerve damage, EMG showed evidence of reinnervation after Wallerian degeneration, and half the nerve fibres had recovered from the conduction block. Thirteen months after nerve injury clinical examination and nerve conduction were normal, but EMG still showed evidence of partial denervation.

Clinical testing of the radiosensitiser Ro-07-0582 II. Radiosensitisation of normal and hypoxic skin

The effectiveness of the radiosensitiser Ro-07-0582 has been tested in man by observing the skin reaction after irradiation using a radio-strontium source with and without administration of the drug. The skin reaction technique has been extended so that skin was irradiated when at low oxygen tension (hypoxic) as well as when fully oxygenated (oxic). Limbs have been made hypoxic by occlusion of the circulation using a sphygmomanometer cuff. To this has been added the prior use of an Esmarch's bandage to reduce the volume of blood in the skin and the enclosing of the limb in a bag of nitrogen. The Oxygen Enhancement Ratios obtained without the sensitiser in nine studies using this system ranged from 1-64 to 2-46. Using Ro-07-0582 skin reactions after oxic exposures were not enhanced but those after hypoxic exposures were markedly increased. The Relative Sensitising Efficiency expresses, as a percentage, the restoration of the sensitivity of cells protected by hypoxia. In six cases where Ro-07-0582 was given in doses ranging from 81 to 165 mg/kg, efficiencies ranged from 27 to 71%. These results can be compared with three studies using metronidazole where efficiencies ranged from 11 to 15%. Using comparable dosage Ro-07-0582 seems approximately three times more effective than metronidazole. In this first study in man, Ro-07-0582 appears to be a highly effective radiosensitiser of hypoxic cells.

Reactive hyperaemia in the human calf after long-lasting ischaemia. A study with strain-gauge plethysmography.

To study reactive hyperaemia in the lower human limb after extended circulatory arrest, blood flow in the calf of 20 patients was measured by strain gauge plethysmography after operations performed in a'bloodless field'. Mean time of ischaemia was 65 min. In 10 patients (group A) the limbs were exsanguinated by a rubber Esmarch bandage before the tourniquet was applied. In another 10 patients (group B) ischaemia was induced after only leg elevation. Epidural anaesthesia caused a significant increase in basal calf flow but did not change maximal flow significantly. This indicates that ischaemia induces a maximal flow of a certain magnitude, which is not related to the level of basal flow. Reactive hyperaemia after 1 h of occlusion compared with 3 min of ischaemia increased mainly by extending recovery time and repayment, which may be attributed to accumulated metabolites maintaining vasodilation. The increase in maximal flow was moderate, which supports the view that the time-response curve for maximal flow shows an exponential-like pattern. The delay of maximal flow observed in most limbs after 1 h of ischaemia may be due to a no-reflow phenomenon. Recovery time (21.4 min) and repayment (184 ml/100 ml) in group A were significantly greater than in group B, whereas maximal flow in groups A and B was 29.4 and 27.8 ml/min/100 ml, respectively, an insignificant difference. Thus, the amount of blood present in the limb during ischaemia may influence reactive hyperaemia, although the maximal postischaemic vasodilation of arterioles is not affected. After 3 min of ischaemia a standard pattern of reactive hyperaemia was recorded, whereas after extended circulatory arrest mainly a biphasic and plateau type of hyperaemic curve was observed.

Tourniquet paralysis.

The principles of the use of the limb tourniquet have been unchanged for over 100 years, but the details of the techniques involved have gradually altered. This paper describes the modern practice of the use of the limb tourniquet in Australia, estimates the incidence of complications and indicates the pressure which may be produced by the Esmarch bandage.

Regional Intravenous Anesthesia

ABSTRACT To the Editor:— The editorial in The Journal of July 26 (193:300, 1965) entitled Regional Intravenous Anesthesia in an example of its use describes the reduction of Colles fracture. A tourniquet is required; an Esmarch's bandage is optional.No comment is made with regard to the potential dangers of interruption of arterial flow to the extremity. Colles fracture almost invariably occurs in the afternoon of life, when vessels are stiff and tissues, particularly nerves, do not endure anoxia kindly. Irreversible injury can and occasionally does occur.The following simple rules have served me well for many years in keeping complications from the use of Esmarch's bandages and tourniquets to a minimum:Circulation is never interrupted nor a limb exsanguinated if (a) the patient is over 45 years of age; (b) there is any history or objective evidence of any sort of peripheral vascular disease, arterial or venous; or

"Oxygen effect factor" of human skin.

The molecular oxygen concentration in biological material at the time of x-irradiation is an important determinant of the magnitude of observed response of mammalian cells. This has been firmly established by many experiments in several laboratories (Gray, 1961). The data show that two to three times as much x-radiation is required to produce a given effect in anoxic as in oxygenated (> 10 mm. HgO2 tension) biological material. That is, the “oxygen effect” factor for cell lethal damage is between 2 and 3. Changes in radiation sensitivity with variations in oxygen tension occur almost entirely in the range of anoxia to marked hypoxia (0–10 mm. Hg). These findings in biological research are of clinical interest since there are areas of necrosis in nearly all carcinomas of significant size. Such necrotic areas were shown by Thomlinson and Gray (1955) in the bronchogenic carcinomas of their study to be at distances from capillaries which would be predicted to be anoxic on the basis of oxygen diffusion coefficient, oxygen utilization by viable cells, capillary diameter, length, and blood flow. If there are anoxic cells in a carcinoma which are viable and replicating, then those cells would be radiation-resistant in comparison with the surrounding normal cells, due to the difference in oxygen tension. Under these conditions an increased clinical effectiveness of radiation therapy would be expected if the oxygen concentration in all of the normal and malignant cells were made the same. We have initiated a study to evaluate the response to x-irradiation of normal and malignant tissue of distal limbs under conditions of local tissue anoxia produced by placing a tourniquet above the lesion. Preliminary determinations of the effect of the tourniquet application on the radiation sensitivity of the skin in the limb were made. Case I: The volar surface of the forearm of a patient (V. S.) about to be treated for an extensive recurrent squamous-cell carcinoma of the dorsum of the hand, was selected as the test site. Three areas of normal skin were irradiated at 60 kv, 2 cm. TSD; circular fields 1.5 cm. in diameter were used and the doses were 2,000, 2,500, and 3,000 rads. The limb was then drained of blood by application of an Esmarch bandage to the full length of the arm. Following this an orthopedic tourniquet was fixed to the mid portion of the upper arm (300 mm. Hg pressure). Under these conditions a parallel set of three skin fields were given 4,000, 5000, and 6,000 rads respectively. The dose in the two series thus differed by a factor of two. Repeat observations revealed that the reaction in the areas treated with normal oxygen tension was a little more severe than in the areas treated while the tourniquet was in place. These results show the “oxygen effect factor” for 60 kv as being ≥2.0.

Production of amputations without exsanguination

A., pointing out a number of disadvantages inherent in the use of the Esmarch tourniquet in operations on the extremities, emphasizes that with interventions without exsanguination according to Esmarch and strict adherence to the anatomical principle, blood loss is also minimal and certainly less significant than it happens as a result of hyperemia after removal harness.

APPARATUS FOR SUPPORT OF LEG IN WHITMAN OPERATION

It has long been the practice at the Hospital for Ruptured and Crippled to do the Whitman operation—astragalectomy and backward displacement of the foot—as well as many others, with the limb made bloodless by the use of an Esmarch bandage. Following the operation the limb was suspended above the bed to obviate as much as possible the danger of swelling following the return of blood to the limb. In theory the suspension was continuous from the moment of application of the plaster. An intern or orderly returned to the ward with the patient on the stretcher holding the limb elevated, and continued so to hold it until it had been secured in suspension by tapes strung from the head to the foot of the bed. In practice it was found that frequent breaks occurred in this technic, and that in almost every case in which swelling occurred to a noticeable