Anesthesia and analgesia
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Anesthesia and analgesia · Sep 1987
Comparative StudyEffects of progressive blood loss on coagulation as measured by thrombelastography.
The effects of progressive blood loss on coagulation were studied in 87 adults (age 23-66 yr) undergoing a variety of operations under general anesthesia. None had preoperative alterations in coagulation or liver function and none were receiving anticoagulant or antiplatelet medication. Whole blood coagulation status was quantitated using thrombelastography (TEG). ⋯ Thrombelastography allowed rapid intraoperative diagnosis and specific treatment of loss of platelet activity in the latter two patients. We conclude that during moderate to massive blood loss, use of supplemental fresh frozen plasma and/or platelets should be reserved for patients with documented defects in coagulation. Thrombelastography is useful for the detection and management of coagulation defects associated with intraoperative blood loss.
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Anesthesia and analgesia · Sep 1987
Comparative StudyCerebral autoregulation and flow/metabolism coupling during cardiopulmonary bypass: the influence of PaCO2.
Measurement of 133Xe clearance and effluent cerebral venous blood sampling were used in 38 patients to determine the effects of cardiopulmonary bypass, and of maintaining temperature corrected or noncorrected PaCO2 at 40 mm Hg on regulation of cerebral blood flow (CBF) and flow/metabolism coupling. After induction of anesthesia with diazepam and fentanyl, mean CBF was 25 ml X 100 g-1 X min-1 and cerebral oxygen consumption, 1.67 ml X 100 g-1 X min-1. Cerebral oxygen consumption during nonpulsatile cardiopulmonary bypass at 26 degrees C was reduced to 0.42 ml X 100 g-1 X min-1 in both groups. ⋯ However, variation in CBF correlated significantly with cerebral perfusion pressure over the pressure range of 15-95 mm Hg. This study demonstrates a profound reduction in cerebral oxygen consumption during hypothermic nonpulsatile cardiopulmonary bypass. When a non-temperature-corrected PaCO2 of approximately 40 mm Hg was maintained, CBF was lower, and analysis of pooled data suggested that CBF regulation was better preserved, i.e., CBF was independent of pressure changes and dependent upon cerebral oxygen consumption.