ABSTRACT
Emergence agitation, also known as emergence excitement, emergence delirium or post anaesthetic excitement is a well-recognized clinical phenomenon occurring in the immediate postoperative period following general anaesthesia.1 Though it is most often seen in children and elderly,2,3 with literature focused on this population, it can affect all age groups. Emergence is the transition from unconsciousness to full wakefulness4 and most often this transition from general anaesthesia is smooth and uneventful.5 Emergence agitation is usually seen during the first 15-30 minutes following awakening from general anaesthesia3,6 and has varied clinical presentation. It can be characterized by agitation, restlessness, hyperactivity, irritability, thrashing, crying, moaning, incoherence and uncooperative behaviour.3,4,6Though emergence agitation is well recognized clinically, it is not well understood. The reasons being, lack of clear definition, lack of reliable and valid assessment tools, difficulty in differentiating between agitation and pain and uncertainty about its clinical significance.2 The incidence reported in paediatric population is 12-13%3 and about 10-15% in geriatric age group.7,8 There are various risk factors recognized to be associated with EA. They are presence of an endotracheal tube or urinary catheter, pain, premedication with benzodiazepine, use of inhalational anaesthetics,3,5 breast, abdominal9 and otolaryngologic surgeries.10,11 Presence of hypoxia, hypothermia, hypoglycaemia, electrolyte disturbances and sepsis can in addition add on to the incidence of EA.3,5
ABSTRACT
Control of post-operative pain is imperative for patient comfort, early mobilization and faster recovery.(1) Specifically, good post-operative pain management has been shown to be effective in reducing peri-operative morbidity associated with acute coronary events and thrombotic events in high risk patients. (2) At the same time, it has been an endeavour to reduce peri-operative opioid consumption and its associated complications. In this respect, an effective multimodal strategy which affords best control of post-operative pain is very important.Increasingly, Regional Techniques are gaining popularity as a part of multimodal post-operative analgesic regimen. Regional Anaesthesia has been shown to reduce the incidence of post-operative nausea and vomiting while also providing benefits that go even beyond patient comfort.Epidural Analgesia is a time tested technique for post-operative analgesia. It has proven efficacy and use of epidural catheters for post-operative analgesia is a norm at many centres. However, the epidural technique comes with its own risk of complications. Also, there are many situations where it would be contraindicated to use the epidural technique. Thus, an equally effective alternative regional anaesthetic technique would be useful in such situations.The Transversus Abdominis Plane (TAP) Block and TAP catheter based continuous blocks are relatively new techniques whose efficacy has been well documented in the scientific literature (3), (4), (5), (6) They are regional anaesthesia techniques which provide analgesia to the skin and muscles of the anterior abdominal wall. (7) It was first described just about a decade ago and has undergone several modifications which in turn have expanded its scope of application for an increasing range of surgical procedures. (8) Their advantage over epidural technique lies in the fact that it does not cause hemodynamic instability. Another advantage is that they can be used in patients with mild platelet or coagulation abnormalities where neuraxial techniques would be contra-indicated. Despite a low risk of complications and a high success rate, it is an underutilized technique. (9)METHODSAfter obtaining ethical clearance certificate from the institution’s ethics committee, a prospective randomized comparative study was conducted among 72 patients, who were to undergo elective lower abdominal surgeries, admitted to Sri Devaraj Urs Medical College Hospital from September 2012 to Aug 2013.Sample SizeIn a previous study by Vandriessche et al A VAS score of 4.8 cm (SD: 1.8 cm) for TAP block group and VAS score of 3.2 cm (SD: 2.1 cm) for epidural group was observed. Assuming similar results, it was calculated that to obtain a power of 80% within a confidence interval of 95%, a minimum of 30 patients were required in each of the two groups. Thus, a total of 60 patients were required at the least. An additional 5% (6 in each group) were taken to account for drop-outs from the study.