Anaesthesia
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Cardiovascular autonomic neuropathy is frequently observed in patients with diabetes mellitus. As anaesthesia has a marked effect on peri-operative autonomic function, the interplay between diabetic neuropathy and anaesthesia may result in unexpected haemodynamic instability during surgery. The objective of this literature review was to examine the association of cardiovascular autonomic neuropathy with peri-operative cardiovascular complications. ⋯ Depending on the type of anaesthesia, the presence of cardiovascular autonomic neuropathy in surgical patients can markedly affect peri-operative haemodynamics and postoperative recovery. Pre-operative testing of the extent of autonomic dysfunction in particular populations, like diabetics, may contribute to a reduction in haemodynamic instability and cardiovascular complications. Non-invasive diagnostic methods assessing autonomic function may be an important tool during pre-operative risk assessment.
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Observational Study
Carboxyhaemoglobin formation and ECG changes during hysteroscopic surgery, transurethral prostatectomy and tonsillectomy using bipolar diathermy.
Diathermy is known to produce a mixture of waste products including carbon monoxide. During transcervical hysteroscopic surgery, carbon monoxide might enter the circulation leading to the formation of carboxyhaemoglobin. In 20 patients scheduled for transcervical hysteroscopic resection of myoma or endometrium, carboxyhaemoglobin was measured before and at the end of the surgical procedure, and compared with levels measured in 20 patients during transurethral prostatectomy, and in 20 patients during tonsillectomy. ⋯ Significant ST-segment changes were observed in 50% of the patients during hysteroscopic surgery. Significant correlations were observed between the increase in carboxyhaemoglobin and the maximum ST-segment change (ρ = -0.707, p < 0.01), between the increase in carboxyhaemoglobin and intravasation (ρ = 0.625; p < 0.01), and between intravasation and the maximum ST-segment change (ρ = -0.761; p < 0.01). The increased carboxyhaemoglobin levels during hysteroscopic surgery appear to be related to the amount of intravasation and this could potentially be a contributing factor to the observed ST-segment changes.