title: Does the use of thiopental provide added cerebral protection during deep hypothermic circulatory arrest?
abstract: A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: Does the use of thiopental provide added cerebral protection during deep hypothermic circulatory arrest (DHCA)? Altogether, more than 62 papers were found using the reported search, of which 7 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Four of the seven papers used thiopental alongside other neuroprotective methods and agents. The methods included the use of ice packs to the head and core systemic hypothermia. Agents used alongside thiopental included nicardipine and mannitol. Thiopental was found to have the ability to lower oxygen consumption, where oxygen consumption was measured using the phosphocreatinine and adenosine triphosphate ratio. The neuroprotective effect of thiopental was evaluated by assessing the electrical activity of the brain during circulatory arrest, by which it was shown to be advantageous. However, other trials suggested that adding thiopental during circulatory arrest did not provide any extra protection to the brain. The timing of thiopental administration is of importance in order to gain positive outcomes, as it's ability to lower the cerebral energy state may result in unfavourable results if added before hypothermic circulatory arrest, where this may lead to an ischaemic event. We conclude that the use of thiopental during deep hypothermic circulatory arrest is beneficial, but if administered too early, it may replete the cerebral energy state before arrest and prove to be detrimental.
authors: School of Medicine, University of Manchester, Manchester, UK.
authors: Sara
authors: S
authors: Al-Hashimi
authors: Mahvash
authors: M
authors: Zaman
authors: Paul
authors: P
authors: Waterworth
authors: Haris
authors: H
authors: Bilal
mesh_terms: D019985:Benchmarking; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D001927:Brain Diseases / Q000209:etiology / Q000378:metabolism / Q000517:prevention & control*; D050792:Circulatory Arrest, Deep Hypothermia Induced / Q000009:adverse effects*; D004734:Energy Metabolism / Q000187:drug effects; D019317:Evidence-Based Medicine; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018696:Neuroprotective Agents / Q000009:adverse effects / Q000627:therapeutic use*; D010101:Oxygen Consumption / Q000187:drug effects; D013874:Thiopental / Q000009:adverse effects / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D018696:Neuroprotective Agents; D013874:Thiopental
keywords: Barbiturate; Cerebral protection; Deep hypothermic circulatory arrest; Thiopental
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