Article Text

Download PDFPDF

Fasting before prilocaine Biers’ block
  1. Muhammad Ahmad, Consultant in Emergency Medicine,
  2. Gary Saynor, Consultant in Emergency Medicine
  1. Department of Emergency Medicine, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WL, UK; kevin


    A short cut review was carried out to establish whether a period of fasting increases the safety of Biers’ block (intravenous regional anaesthesia). A total of 50 papers were found using the reported search, of which four presented the best evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results, and study weaknesses of these best papers are tabulated. A clinical bottom line is stated.

    Statistics from

    Request Permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

    Report by Muhammad Ahmad, Consultant in Emergency MedicineChecked by Gary Saynor, Consultant in Emergency Medicine

    Clinical scenario

    A 75 year old man presents to the emergency department with a wrist injury. X ray reveals a Colles’ fracture with dorsal angulation requiring manipulation. The patient has had lunch one hour before presentation. Your colleague tells you that you should manipulate the fracture before your shift ends in an hour’s time, but a passing anaesthetist says that you should wait at least five hours (six hours after food) before you do anything. The departmental manager points out that this means the patient should be admitted since they will “breach” the target time of four hours if you wait. If the patient is admitted the next available trauma list is in 36 hours. You wonder whether the patient should be fasted for four to six hours or if it is safe to reduce this fracture under Bier’s block without any period of fasting.

    Three part question

    In [patients with uncomplicated Colles’ fracture] is [fasting before prilocaine Biers’ block] necessary for [the prevention of life threatening complications]?

    Search strategy

    Medline 1966–week 3 March 2005 and Embase 1980–week 13 2005 using the OVID interface, and Cochrane Library Issue 1 2005. Medline: [(biers adj OR exp nerve block/OR exp anesthesia, local/OR exp anesthesia, conduction/)] AND [(exp fasting/OR] Limit to Human and English. A total of 40 papers found. Embase: [biers adj OR exp nerve block/OR exp regional anesthesia/OR exp intravenous anesthesia/] AND [ exp dietary restriction/OR exp food deprivation/OR] Limit to Human and English. A total of 28 papers found. Cochrane Library: “biers block” [all fields] OR Colles’ Fracture (Mesh) AND Fasting (Mesh). A total of 32 articles found.

    Search outcome

    Overall 50 papers were found, of which 47 were not relevant to the study question. All the references in the relevant papers were searched and two more papers were found. Four papers are included in table 1.

    Table 1


    The evidence found does not address the question directly and is limited to postal surveys. All studies showed that major complications are extremely rare in both groups and, where the question was addressed, there is no evidence of increased rate of complications in patients who were not fasted.


    The limited evidence available suggests there is no need to fast patients prior to Biers’ block. Further research is required.

    Report by Muhammad Ahmad, Consultant in Emergency MedicineChecked by Gary Saynor, Consultant in Emergency Medicine