Postgrad Med J: first published as 10.1136/pgmj.43.503.592 on 1 September 1967. Downloaded from Postgrad. med. J. (September 1967) 43, 592-598. Resuscitation-fluid replacement W. G. PROUT R. VAUGHAN JONES M.B., F.R.C.S. M.B., M.R.C.P., M.C.Path. Surgical Registrar, Consultant Pathologist, St Peter's Hospital, Chertsey, and St Thomas' Hospital, London North West Surrey Group Laboratory St Peter's Hospital, Chertsey THIS short account will be confined to the dromes with no common single clinical manifesta- management of circulatory failure in the first few tion. hours after reception of the patient in a Casualty Bloch et al. (1966) define shock as a state of Department. Where shock is due to trauma the progressive circulatory failure in which the cardiac cause will usually be obvious, but many shocked output is insufficient to meet tissue requirements cases brought to Casualty Departments suffer for nutrition, oxygenation or waste disposal. This from other diseases in which circulatory failure definition serves to emphasize the basic patho- may be complex in origin. For this reason we have logical feature, that of defective tissue perfusion. also discussed non-traumatic causes. For the different forms of shock, further terms have been introduced. Shires (1967) has suggested Traumatic shock subdivision into haematogenic, neurogenic, vaso- It is generally agreed that reduction in the genic and cardiogenic forms, but these are termsby copyright. circulating blood volume is the main factor in the without therapeutic implication. McGowan & production of traumatic shock. When external or Walters (1966) point out that clinically two internal haemorrhage takes place, the fluid lost is, patterns of circulatory upset are most often seen of course, blood. When there is extensive burning -cold hypotension and warm hypotension, terms an increase in capillary permeability leads to a first suggested by Grant & Reeve (1951, p. 225). massive exudation of plasma-like fluid with reduc- tion in the plasma and extracellular fluid volumes. Cold hypotension Crushing injuries may cause not only frank This refers to classical traumatic shock charac- haemorrhage but also the accumulation of a terized by low blood pressure (systolic pressure plasma-like inflammatory exudate in the damaged less than 100 mmHg), high pulse rate (greater than tissues with reduction in the plasma volume and 100/min) low pulse volume and usually cold pale http://pmj.bmj.com/ hence the blood volume. extremities. Central venous pressure (CVP) is low. Reduced cardiac output and peripheral Electrolyte changes arteriolar constriction are associated with this type After trauma in the normal subject oliguria and of shock. reduced renal sodium output are the rule, whereas This condition may be the result of oligaemia, renal potassium output is increased. Plasma acute myocardial failure, pulmonary embolism, sodium levels are reduced but this does not infection especially that due to Gram-negative on September 30, 2021 by guest. Protected indicate sodium depletion and is not an indication organisms, or pancreatitis. for therapy with isotonic or hypertonic saline (Sevitt, 1966). Plasma potassium levels may rise, Warm hypotension sometimes rapidly if there has been considerable Here the blood pressure is low with high pulse damage to muscle. If oliguria persists hyper- rate and full pulse volume, while the extremities kalaemia may necessitate the administration of are commonly warm and dry. CVP is normal or a resins or some form of dialysis (Gallagher & little reduced. Polak, 1967). In this type of shock the cardiac output is probably undiminished but there is a decrease in Terminology arteriolar tone. Shock, a term hallowed by some 200 years Warm hypotension is found in response to usage, defies precise definition, for it represents infection, pancreatitis, following treatment of cold not a single syndrome but a collection of syn- hypotension, in response to drugs, e.g. anaesthetic Postgrad Med J: first published as 10.1136/pgmj.43.503.592 on 1 September 1967. Downloaded from Resuscitation-fluid replacement 593 agents and barbiturate or phenothiazine group (a) Intravenous infusion overdosage, and in alcoholism. In the last two In the severely injured patient, particularly if groups of patients circulatory reflexes are blocked old or suffering from concurrent disease, monitor- (Barraclough & Sharpey-Schafer, 1963) and shock ing of the central venous pressure is desirable and may develop when they are subjected to relatively an intravenous catheter should be introduced so minor traumata. that its tip lies in a great vein. It must be emphasized that these two states are If oligaemia and venoconstriction make per- not clear-cut subdivisions, and intermediates may cutaneous cannulation difficult, time should not be found: indeed, the patient may pass from one be wasted on a prolonged search for a suitable to the other during the course of an illness. vein; instead a cut-down should be performed. A 12-in. catheter may be introduced via the Pathophysiology of shock antecubital vein into the axillary or subclavian The changes which occur in uncomplicated veins. If care is taken that the tip of the catheter oligaemic shock are well known. Reduction of does not impinge on the valve at the lower border circulating blood volume stimulates baroreceptors of the subscapularis, an accurate measurement of causing an increase in the rate and force of the the central venous pressure is obtained. cardiac beat, constriction of veins, venules and of the regional peripheral arteriolar beds, all the Note: If an Intracath (Bard-Davol) or Needle and result of adrenergic stimulation (Mollison, 1967, Cathether (Portex) is used at the elbow, care must be taken The that the needle cutting edge is guarded, and the elbow firmly p. 153). blood flow to the splanchnic area, splinted so that the catheter cannot be severed by play skin, muscle and kidneys is considerably reduced against the sharp end of the needle. and blood is diverted to the cerebral and coronary vessels (Freeman, 1963). Some authors (Borow et al., 1965) have In healthy young adults without cardio- suggested using the external jugular or cephalic pulmonary disease these changes occur after a loss veins, but there may be difficulty in negotiating the of about 30% of the blood volume (approximately valves which guard the terminations of those by copyright. 3 pints): as the blood loss approaches 50% the veins. compensatory vasoconstriction is no longer If none of these veins is suitable, percutaneous adequate and death is imminent if transfusion is cannulation of the femoral vein is performed: the withheld (Grant & Reeve, 1951, p. 205). needle is introduced just below the skin crease, 1 cm medial to the femoral artery. It is passed in a Irreversible shock backward and upward direction to enter the In recent years much experimental and clinical femoral vein where it is supported by the superior attention has been directed to this state. Many pubic ramus. Through it the catheter may be patients who would formerly have come within the this category are now effectively treated and the passed into inferior vena cava. A greater incidence of thrombo-embolic phenomena make http://pmj.bmj.com/ diagnosis of irreversible shock should only be this route less desirable (Wilson et al., 1962). made retrospectively when the patient dies of Long saphenous cut-down at the ankle is tech- shock. nically easy but makes CVP measurement impos- Nevertheless, the term is sometimes used loosely sible. to denote a state of persistent circulatory failure despite adequate blood volume replacement. Perhaps a better term is 'refractory shock' (Smith (b) Immediate investigations A specimen of blood for grouping and & Moore, 1962) from which the patient might match- on September 30, 2021 by guest. Protected recover or pass into true irreversible shock with ing should be despatched to the laboratory as soon ensuing death. as possible. This does not, however, take pre- The mechanisms involved in irreversible shock cedence over infusing the patient, should direct are beyond the scope of this article-an excellent venepuncture prove difficult. account is given by Bloch et al. (1966). Haemoglobin and haematocrit estimations are valuable as they provide a baseline for retrospec- Practical management of shock tive assessment even although they do not Shock from traumatic causes. In traumatic accurately reflect the blood loss until haemo- shock, oligaemia is the result of external or dilution has occurred over the first 48 hr. internal blood loss, or of plasma loss from Similarly, initial determination of the plasma damaged capillaries in the traumatized region. The electrolytes and blood urea may be useful, and a several facets of resuscitation of the shocked specimen of separated plasma, retained overnight patient are most conveniently considered in the refrigerator, may be analysed at a con- separately. venient time. Postgrad Med J: first published as 10.1136/pgmj.43.503.592 on 1 September 1967. Downloaded from 594 W. G. Prout and R. Vaughan Jones (c) Fluids for infusion Abnormal bleeding has followed the use of large Whole blood. Where haemorrhage has occurred quantities of dextran (Hardisty & Ingram, 1965). blood is the correct replacement fluid, although There is evidence that the bleeding tendency is some other fluid may have to be given while it is most severe with fractions of large average mole- made ready. Unmatched blood should only be cular weight but no clear picture is available of the given in dire emergency and it clearly behoves'a quantity of dextran which can be tolerated with- new casualty officer to find out what arrangements out causing bleeding. Mollison (1967, p. 175) sug- exist in his hospital for the rapid matching of gests that in ordinary circumstances it is best to blood. limit to 1 litre the amount of dextran given but it When very large quantities of stored blood are is clear that in the treatment of burns this amount given rapidly, e.g.