Adequate Fluid Administration Research Articles

Traitement de l'hypovolémie chez le traumatisé craniocérébral

The appropriate administration of intravenous fluids in neurosurgical patients remains an area of disagreement between neurosurgeons and anaesthetists. Fluid restriction has long been advocated by the former and is widely believed to reduce or prevent the formation of cerebral oedema. However, such restriction can lead to hypovolaemia which in turn can result in haemodynamic instability. Thus, brain homeostasis should be aimed for through adequate fluid administration and normal or slightly elevated mean arterial pressure. The properties of the endothelium differ between the brain and the remainder of the body. In most non CNS tissues the size of the junctions between endothelial cells averages 65 Å. Proteins do not cross these gaps while sodium does. In the brain, the junction size is only 7 Å, which is too small to allow crossing by sodium. Investigations with changes in osmotic and oncotic pressure have demonstrated that : 1) reducing osmolality results in oedema formation in all tissues including normal brain ; 2) a decrease in oncotic pressure is only associated with peripheral oedema but not in the brain ; 3) in case of brain injury, a decrease in osmolality elicits oedema in the part of brain which remained normal ; 4) similarly, a decrease in oncotic pressure does not cause an increase in brain oedema in the injured part of the brain. Thus, a major reduction in oncotic pressure is unimportant for the brain, whereas changes in total osmolality are the dominant driving force at this level. To conclude, in a hypovolaemic patient with severe head injury, the cristalloid of choice is NaCl 0.9 % and the colloid of choice is hydroxyethylstarch, both with an osmolality > 300 mosm · kg −1. Ringer-lactate is hypoosmotic (255 mosm · kg −1) and may cause or increase cerebral oedema. Mean arterial pressure should be maintained above 80 mmHg.

Septicaemic-endotoxic shock: problems of early diagnosis and treatment (author's transl)

At least in its early stage, the syndrome of septicaemic-endotoxic shock gives rise to a heterogeneous clinical picture which often lacks definite clinical, haemodynamic and biochemical features. But even if this form of shock is merely suspected, adequate fluid supply and administration of appropriate antibiotics should be started, in addition to general supportive measures. The administration of vasoactive drugs and corticosteroids has provided favourable results. The low early mortality (10 among 50 patients) is probably due to the medical causes which precipitate shock in this group, and the early onset of treatment.

Anaesthetic management of pheochromocytoma: A case report

The anaesthetic management of a patient with pheochromocytoma is discussed. The following points should be considered when treating such patients: 1. Preoperative preparation with adrenergic blocking agents, following the criteria of Harrisonet al.4 2. Use of an anaesthetic agent (methoxyflurane or fluroxene) which is not associated with release of endogenous catecholamines and does not sensitize the myocardium to high levels of circulating catecholamines. 3. Adequate fluid and blood administration, including preoperative transfusion if necessary. 4. Careful monitoring during surgery, including direct arterial pressure, central venous pressure, electrocardiogram, urinary output, and blood gas determinations. 5. Ready availability of all pharmacological agents appropriate for the control of hypertension, hypotension, and cardiac arrhythmias.