Preoperative Assessment and Medication

In all cases, anesthetic care starts with a pre-operative visit and assessment by the anesthesiologist, who will be interested in the patient's general health, comorbidities, current medications and known allergies. For emergency cases, the time of last oral intake of food and fluids is important. The neurological status will be evaluated with particular regard to specific deficits, evidence of raised ICP, brainstem dysfunction and, in the case of cervical spine surgery, stability of the cervical spine.

Investigations will depend on the patient's age, medical condition and the proposed surgery, and institutions will have their own guidelines for investigations as well as for the amount of blood to be cross-matched before specific procedures. The perioperative management of coexisting diseases such as diabetes mellitus and ischemic heart disease is part of the anesthesiologist's responsibility, in consultation with other specialists.

Pre-operative medication is sometimes prescribed in order to provide anxiolysis and sedation, and a drying and vagolytic agent may also be given. Other drugs, such as beta-blockers, may be prescribed for specific indications. Sedative pre-medication is commonly a benzodiazepine or opioid, but sedatives should be used with caution in patients with evidence of raised ICP. Vagolytic drugs, such as atropine, glycopyrrolate and hyoscine, are given to dry oral secretions and to block undesirable vagal reflexes such as bradycardia. A drying agent is particularly important in patients who are to undergo fiberoptic intubation. Glycopyrrolate is preferable to atropine in neurosurgical patients, as it does not cause the same degree of tachycardia. Hyoscine causes sedation and can be associated with delayed recovery, making it unsuitable for craniotomy patients. It can be used before spinal surgery but is best avoided in older patients in whom it can cause post-operative confusion. In general, it is best for patients to take their usual medications, apart, perhaps, from diuretics, on the morning of surgery.

Guidelines for fasting before surgery aim to prevent pulmonary aspiration of gastric contents whilst avoiding dehydration from prolonged fasting. Fasting times of 2 hours for clear fluids, 4 hours for milk and 6 hours for solids have been shown to be safe in patients with normal gastric emptying. Those with raised ICP causing vomiting are at risk of dehydration and may require pre-operative intravenous fluids.

Diabetes 2

Diabetes 2

Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...

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