Comparison of propofol and thiopentone along with ketamine for paediatric MRI sedation

Abstract

INTRODUCTIONMagnetic resonance imaging (MRI) requires the patient to stay still for at least 15 minutes to one hour in a noisy and claustrophobic environment. It is difficult especially in infants and children without drug induced sleep. Hence anaesthesiologists are discovering safe and successful combination of drugs. 1Propofol is discussed to be a best of all intravenous (I.V.) drugs for paediatric sedation because of its faster induction and quick recovery.2 Magnetic resonance imaging scanning for children is a big challenge for anaesthesiologist for providing adequate sedation without compromising airway and haemodynamics. 3 The success of sedation during MRI is typically assessed by two factors 1) safety during sedation 2) successful completion of test that is good quality of radiological image without artefacts. It can be achieved from motion less body during scan. 4 Propofol yields faster induction and faster emergence from sedation but it may cause hypotension. 5Thiopentone I.V bolus has been used routinely 6 but the duration of recovery and sedation is unpredictable. 7 We aimed to study the effectiveness between Propofol and Thiopentone along with Ketamine and other premedications. ABSTRACTBackground: Children are very much scared to undergo magnetic resonance imaging (MRI) brain or any body part even along with their parents for about 15 to 25 minutes. We investigated the combination of Propofol Ketamine and Thiopentone Ketamine along with Glycopyrolate and Midazolam premedication to see safe and better sedation group for paediatric MRI. Methods: We investigated randomly 50 children of age three to five years prospectively. Children were premedicated with Glycopyrolate 0.01 mg/kg and Midazolam 0.05 mg/kg per body weight intravenously. Ketamine 1 mg/kg body weight was given just before shifting into the MRI machine. After body positioning either Propofol (PK group) or Thiopentone (TK group) 1 mg/kg body weight was given slowly. Children were monitored for electrocardiogram (ECG), arterial oxygen saturation (SpO 2 ) and respiratory rate continuously. Oxygen supplementation was through the oxygen (O 2 ) mask. Three parameters were studied 1) Repetition of drug 2) Respiratory distress during scan period and 3) Recovery time. Results: The pre-interventional characteristics including age, sex, weight, ASA grade, were comparable between two groups (p>0.050). Repetition in PK group was high compared to TK group (40% vs 8%; p=0.0081). Respiratory distress was comparable in both the groups (16% vs 24%; p=0.480) whereas recovery time was significantly shorter for PK group (4.62 ± 0.53 vs 9.86 vs 1.28; p<0.001). Conclusions: Thiopentone Ketamine combination results in lower repetition rate while Propofol Ketamine offers shorter recovery period. However, respiratory distress is almost similar.