Evaluation of paediatric regional anaesthetic procedures in the head and neck region

Abstract

Advancements in the medical field with regard to the development of new techniques, reassessment and analyses of the old and unsatisfactory techniques and the expansion and improvement of acceptable techniques have led to an increase in the use of regional anaesthetic nerve blocks in paediatric patients. However, several regional anaesthetic procedures are currently not being performed by anaesthetists due to the high number of complications and difficulties experienced. Some medical practitioners are under the impression that they lack the knowledge and confidence to perform these regional nerve blocks, especially on neonatal and infant patients. In order to assist these doctors in refining their anatomical knowledge and increasing their confidence in performing these nerve blocks, the procedures which are experienced as problematic need to be identified and evaluated. The aim of this study was therefore: (1) to establish the most efficient method of blocking the maxillary nerve within the pterygopalatine fossa; (2) to investigate which head and neck regional nerve blocks are performed most frequently on paediatric patients and identify problem procedures that are performed by practicing anaesthesiologist in South Africa; (3) to develop a clinical anatomy information base for the selected procedures. Three methods / techniques for maxillary nerve blocks were simulated and compared on 24 dry paediatric skulls and 30 dissected paediatric cadavers. The depth and angles at which the needle travels to block the maxillary nerve in the pterygopalatine fossa, after existing the skull through the foramen rotundum, was measured and compared. The method using the supra-zygomatic approach (method B), from the frontozygomatic angle towards the pterygopalatine fossa, exhibited no statistical significance (p > 0.05) when comparing the measurements in the skulls and cadavers. Method A, a supra-zygomatic approach from the midpoint on the lateral border of the orbit, as well as method C, an infra-zygomatic approach with an entry at the site of a vertical line extending along the lateral orbit wall, showed statistical significance when comparing measurements in the skulls and cadavers. It can therefore be concluded that method B produces the most consistent data and should be tested in a clinical setting. Seventeen commonly performed paediatric regional nerve blocks were identified. A detailed questionnaire was completed by 111 respondents, either electronically or from others attending either the Pain Interventions and Regional Anaesthesia Conference or the South African Society of Anaesthesiologists Conference. Difficulties in performing the regional anaesthetic nerve blocks, and complications encountered, were the main areas of focus, when selecting the four problem procedures. The problem procedures selected are the following: supra-orbital and supra-trochlear nerve blocks, infra-orbital nerve block (Extra-oral approach), superior laryngeal and recurrent laryngeal nerve blocks. A detailed anatomical information base was developed through an extensive literature review. This will aid in educating and facilitating doctors in performing paediatric regional nerve blocks, thereby enabling them to successfully practice medicine.