The Can t Intubate Can t Oxygenate Scenario in Paediatric Anaesthesia: An Animal Model

Transcription

1 The Can t Intubate Can t Oxygenate Scenario in Paediatric Anaesthesia: An Animal Model Stacey J, Heard AMB, Chapman G, Wallace CJ, Hegarty M, Vijayasekaran S, von Ungern-Sternberg BS Gilbert Brown Prize Session, ANZCA ASM 2012

2 Introduction The Can t Intubate Can t Oxygenate (CICO) scenario is rare in paediatric anaesthesia There is little evidence to guide its management, particularly as regards the infant or neonate Existing guidelines are conflicting and extrapolated from the adult data Cote CJ, Hartnick CJ. Pediatr Anesth 2009 Caplan et al. Anesthesiology 2003 APAGBI ( Weiss M, Engelhardt T. Pediatr Anesth 2010

3 APAGBI Guidelines

4 Objective To compare two intravenous cannulae of different gauge for ease of use, success rate, and complication rate in needle tracheotomy of a post mortem animal model of the infant airway

5 Methodology Two experienced proceduralists repeatedly attempted cannula tracheotomy in five post mortem rabbits, alternately using 18G and 14G Insyte TM cannulae (BD, Franklin Lakes, NJ, USA) Attempts began at the first tracheal cartilage, with subsequent attempts progressively more caudad 12 attempts were made in each rabbit

6 Methodology 2 The proceduralist rated each attempt for Ease of insertion (for both loss of resistance and cannula advancement over needle) Confidence of successful placement Ability to aspirate with or without manipulation of the cannula Success was defined as bronchoscopic evidence of intra-tracheal cannula placement to which the proceduralists were blinded The bronchoscopic footage was later reviewed for evidence of tracheal trauma

7 Results: Rabbit Characteristics Median 3.9kg ( kg). Median tracheal diameter 3.5mm (3-4mm)

8 Results: Success and Ease of Use Cannula tracheotomy had a 60% success rate No significant difference in success rate between gauges 18G 66.6%, 14G 53.3% There was no difference in proceduralistrated ease of use between cannulae

9 Successful Cannula Placement

10 Successful Cannula Placement

11 Results: Predictors of Success Successful aspiration 97% Positive predictive value Easy cannula advancement 70% Easy loss of resistance 69% Confidence of success 55%

12 Results: Aspiration Successful aspiration highly predictive (ppv 97%) of success highly sensitive (sensitivity 89%), and highly specific (specificity 96%) for tracheal cannulation

13 Results: Complications The posterior wall was perforated in 42% of tracheal punctures Likelihood with an 18G twice that with a 14G Gradual withdrawal under continuous aspiration enabled tracheal cannulation in 88% of such cases The cannula was initially kinked in 8% of tracheal punctures No difference between gauges On each occasion, kink righted itself on gradual withdrawal

14 Posterior wall perforation

15 Posterior Wall Perforation

16 Limitations Attempts were not timed nor under situational stress, and ability to insufflate the lungs was not tested Success rates were not evaluated for other, less expert, practitioners Significance of posterior wall perforation not addressed

17 Comparable studies In a rabbit study, emergency cricothyroidotomy using the Quicktrack Baby TM (VBM Medizintechnik, Germany) was successful in ten of ten attempts within a median of 31 seconds (23-43s) Metterlein T et al. Pediatr Anesth 2011

18 Comparable Studies 2 In a post mortem porcine model Modified surgical tracheostomy had a higher success rate than cannula cricothyroidotomy (8/10 vs. 8/30, p=0.05) Cannula cricothyroidotomy had a tendency to be faster (median 68 seconds vs. 89 seconds, p=0.08) Johansen et al. Pediatr Anesth 2010

19 Conclusions Cannula tracheotomy in a model comparable to the infant airway is difficult and not without complication. Successful aspiration is the key predictor of tracheal placement Further studies are required to compare Alternative cannulae and insertion techniques Including commercially-available devices Surgical techniques Techniques for oxygenation and ventilation once tracheal access secured

20 Acknowledgements Veterinary and laboratory staff at the University of Western Australia, without whom this study would not have been possible.