Perpetual Paediatric Problems
The meeting was opened by Dr Debbie Nolan, the President of the Section of Anaesthesia of the Manchester Medical Society who welcomed all the delegates to the meeting and introduced the first speaker, Dr Peter Mark Fortune who spoke on the transfer of the critically ill child.
1) Stabilisation and transfer of the critically ill child – pearls and pitfalls
Dr P-M Fortune, Clinical Director of Critical Care, Central Manchester and Manchester Children’s University Hospitals NHS Trust
Dr Fortune began his talk with the reasons for the increasing numbers of transfers of critically ill children to regional centres. Firstly, paediatric intensive care has been centralised to regional units and there was a growing reluctance by both paediatricians and anaesthetists to perform occasional paediatric intensive care practice. More treatment modalities were becoming available and there was a mounting public expectation that all critically ill children should be treated with the best services available. This has led to greater numbers of inter-hospital transfers which now average about 6,000 cases per year, of which 75% are transferred by specialist paediatric intensive care teams. The rest are transferred by District General Hospital teams to the regional centre, due to either the paediatric team being busy or to ensure minimal delay; for example in the case of an expanding intracranial lesion. Dr Fortune emphasised that the key to a successful transfer is communication between the District Hospital and the regional centre.
Dr Fortune then went onto look at the commonalities between paediatric and adult transfers, such as the airway, breathing, circulation and not forgetting dextrose in children. However, he emphasised that there were key differences with children; in particular their greatly reduced energy and fluid reserves and their poor thermal control due to their large body surface area to volume ratio. Hypothermia is associated with poor outcome. Because of the often smaller size of children, they are best secured with a vacuum mattress during transfer.
Dr Fortune then talked about what he felt was best practice. In particular he said the choice of oral or nasal endotracheal tube was immaterial, providing that a chest X-Ray had been taken prior to transfer confirming correct placement in the trachea. He emphasised the importance of end-tidal C02 monitoring during transfer. He talked about venous access and recommended the use of ultrasound guidance in placing these lines in a similar way to adult practice, and recommended the use of intra-osseous needles, particularly the EZ-IO system.
Dr Fortune then went over some scenarios. Firstly, he talked about trauma, particularly with regards to spinal cord injury. He emphasised the importance of leaving a collar on and maintaining full spinal care, even in the presence of no radiological abnormality. Psychologically children grow younger when they are sick, and Dr Fortune emphasised the importance of realistic expectations given to parents for critically injured children.
Dr Fortune went on to talk about the sick stable child and his view that when in doubt, sick children should always be intubated prior to transfer. However, once intubated, he said that it was inappropriate for a child to be transferred without an anaesthetist being present. The sick unstable child was then covered, usually as a result of severe sepsis and the importance of large volumes of fluid was stressed. Dr Fortune thought these children should always be intubated early and their treatment should be pro-active rather than reactive. Other unstable scenarios included congenital cardiac disease. These usually presented in the first month of life with the closure of the ductus arteriosus, which was often worsened by the administration of excessive amounts of oxygen which will further close the duct to make the child more unstable. He talked about the management of the unstable child with seizures, but emphasised that there was not always a reason to intubate these children, providing the full protocol of anti-convulsants had been given, including Paraldehyde. It was often the practice of the paediatric ICU to rapidly extubate these children after transfer. Assuming that adequate doses of anti-convulsants had been given, these children woke up rapidly and rarely fit again.
Finally, Dr Fortune looked at the problem of complex “special” children, and whether it was appropriate to transfer them to paediatric intensive care units. Dr Fortune stated the importance of discussing these cases with the referring paediatricians fully. Finally, he spoke of out of hospital arrest and the universally poor prognosis of children who have not been successfully resuscitated within 20 minutes. Dr Fortune said it was often easy to get a heart to beat again following a hypoxic insult with a large dose of adrenaline, however the hypoxic cerebral injury was rarely reversible unless the child had become rapidly hypothermic, and urged resuscitation teams to stop rather than try and save an irretrievable situation.
Dr Fortune said it was important to set up an appropriate transfer kit which should be checked regularly and the transferring doctor should know how it all worked. For drug details, he gave a website address of www.crashcall.net which had an informative spreadsheet for the calculation of paediatric emergency drugs.
In summary, Dr Fortune said that the secret to a safe transfer was proper preparation.
2) The Role of the European Resuscitation Council and the Guidelines
Dr J Smith, Consultant Anaesthetist, Great Ormond Street Hospital for Children NHS Trust
Dr Smith started his talk by explaining how the European Resuscitation Council updated their guidelines. An international liaison committee on resuscitation reviews published evidence every five years and in January 2005, there was a consensus meeting followed by the publication of new guidelines in November 2005. Dr Smith started by stating what we knew for sure.
Firstly, children usually suffer from secondary cardiac arrest and in 90% of cases, this was preceded by bradycardia and the survival in respiratory arrest was good with 70% of children normal a year later. Bystander CPR is associated with an improved survival, however, rescuers often do nothing because of the fear of causing harm. He said that previously, basic life support guidelines were different for adults and children. In order to simplify these, they were made the same for infants, children and adults, with a compression to breath ratio of 30:2. Dr Smith spoke about a paper by E. Dorph, L. Wik and P. A. Steen. (Resuscitation 2002;54:259) which looked at the difference in ventilation:compression ratios on coronary perfusion pressure and ventilation. He then looked a paper by Babbs CF & Kern KB (Resuscitation 2002;54:147-57) which concluded that compression to ventilation ratios in CPR should be smaller for children, and that optimal CPR in children requires relatively more ventilation than optimal CPR in adults. However, on the basis that something is better than nothing, a compromise was reached by allowing only minimal necessary modifications to the adult protocol for basic life support.
Dr Smith then looked at automated external defibrillators which were increasingly available in many public places and were excellent at detecting ventricular fibrillation. VF is very uncommon in children, and there is real fear about either too large a shock to a child in VF or giving a child any shock when they were not in VF. A paper by Babbs et al. (Am Heart J 1980;99:734-738) shows the LD50 of shock was 470 joules/Kg. However the lethal dose of a child in VF was 0 joules per kilo. Dr Smith reviewed several papers looking at the sensitivity and specificity for ventricular fibrillation which showed the reliability of these devices in this situation. Dr Smith then looked at the dose of adrenaline in cardiac arrests and stated there was only one paper which appeared to show any benefit of the higher dose of 100 micrograms/kilo of adrenaline, and a paper from Perondi et al (NEJM 2004;250:1722-30) showed a significantly reduced survival from asphyxial arrest in the high dose adrenaline group.
In the final section, Dr Smith looked at airway management. In particular he described a paper looking at the effect of out of hospital paediatric endotracheal intubation on survival and neurological outcome by Gausche M et al (JAMA. 2000 Feb 9;283(6):783-90). This paper was a prospective randomised controlled trial of a large number of consecutive patients and showed that there was no significant difference between children that were intubated and those that were ventilated with a bag and mask, with the only major complication from the bag and mask technique being greater gastric distension. He looked at the role of laryngeal mask airways and noted that a paper from 1996, Lopes Gill et al, showed there was a problem in up to one third of patients when these were inserted by trainee anaesthetists, unfamiliar with their use in children.
Dr Smith then looked at the increasing use of cuffed endotracheal tubes in children and noted that the complication rate from the tubes were the same as the uncuffed. He then passed through the use of the laryngeal tube airway device which was shown in a paper by Bortone L et al (2006. Paed Anaesth;16:251-7) to be even less successful than the laryngeal mask airway in its use in emergency.
Finally, like the speaker before he emphasised the important of end-tidal CO2 monitoring in tracheal tube placement and its usefulness during cardiac arrest. Dr Smith concluded by stating that the paediatric resuscitation guidelines for 2005 are evidence-based and they have been made simpler for both professional and lay rescuers.
3) Fluid therapy
Dr F Potter, Consultant Anaesthetist, Royal Liverpool Children’s Hospital NHS Trust
Dr Potter started by looking at one of the original papers by Holliday MA & Segar WE. (Pediatrics 19;823-31 1957). This paper linked fluid requirement to energy expenditure and to weight. Small babies had high energy needs and therefore high water requirements, and these reduced as children got older. From this paper came the standard teaching of 4 mls/kg/hr for the first 10kgs, 2 mls/kg/hr for the second 10 kgs, and 1 ml/hour for every kg above 20. Having dealt with the volume aspect, he then looked at the solute contents of the fluids. He again looked at the work of Holliday and Segar who had measured electrolyte excretion in infants. Through their research, they had come to the conclusion that one fifth normal saline made isotonic with dextrose was the ideal fluid for these patients. SGE Lindahl (Anaesthesiology 69:377-382 1988) looked again at fluid therapy in infants and children and came to the conclusion that hyponatraemia was common although rarely clinically important.
Dr Potter then went onto the child undergoing surgery and looked at the requirements to make up the starvation deficit, intra-operative maintenance, extra cellular and third space losses and blood loss. From research presented, Dr Potter pointed out that it was frequent for children to be starved for in excess in ten hours prior to surgery, and there was a significant incidence of hypoglycaemia. However, with the stress response to surgery, most children increase blood glucose over the course of surgery without glucose containing fluids having been given. Because of the better understood adverse effects of hyperglycaemia there has been a move away from glucose containing solutions. Hartmann’s solution was now the most commonly used intravenous fluid because of the potential problems for hyperchloraemic acidosis with 0.9% saline.
Dr Potter then looked at hyponatraemia, with a paper by EJ Hoorn, D Geary et al (Pediatrics (2004) 1279-84) which found that hyponatraemia was very common. Acute severe hyponatraemia can lead to brain swelling, death and other poor neurological outcomes. This may occur when hypotonic fluids are given in a volume that exceeds the capacity of the kidney to excrete it, especially in the presence of ADH.
Dr Potter then looked at the 2007 APA Consensus Guidelines on peri-operative fluid management. These clarify the starvation guidelines. They also continue to follow the maintenance fluid guidelines originated from Holliday and Segar of 4, 2 & 1. They recommended the avoidance of dextrose containing fluids for children over 6 months, and stress the importance of treating acute hyponatraemia rapidly.
In summary, Dr Potter asked the audience to consider whether children actually needed intravenous fluids and pointed out that, despite the fact that Holliday and Segar had over-estimated the volumes of water required for maintenance, it was still a reasonable starting point. A maintenance fluid isotonic solution should be used. Using fluid formulae does not absolve the practitioner from checking for hypoglycaemia and hyponatraemia.
4) North of England Cleft Foundation – aspects of paediatric cleft care in Southern India
Dr R G Teturswamy, Consultant in Palliative Care, East Lancashire Hospitals NHS Trust
Dr M R Tremlett, Consultant Anaesthetist, South Tees Hospitals NHS Trust
Dr George Teturswamy, spoke about the background of his involvement in paediatric cleft care in Southern India. From a small idea on a wintry afternoon in a Blackburn operating theatre, this had now become a regular event in both Mysore and Hyderabad.
Dr Michael Tremlett from Middlesborough then spoke about his personal involvement in the North of England Cleft Foundation.
Dr Tremlett looked at the implications of a cleft deformity in a child. Apart from the cosmetic deformity causing changes in life chances, there were significant speech and feeding impairment and a higher incidence of middle ear disease. He pointed out that anaesthesia for this surgery had its particular problems. Apart from the paediatric population with other associated congenital abnormalities, airway and intubation problems were common. He then contrasted techniques for this surgery in the UK and how they had to be adapted to practice in India. Dr Tremlett then looked at the funding and logistics of a camp. He described the facilities that were usually available and the equipment he regularly took. He described the anaesthetic technique and particularly stressed the excellent postoperative care because of the high number and calibre of nursing staff available.
Dr Tremlett then looked at the ethical issues, and in particular who gained from this service. Firstly he thought that patients gained by high quality safe surgery and anaesthesia, and secondly when UK trainees are taken on these camps, they got a great deal of supervised paediatric experience which would be much more difficult to come by in the UK. For Dr Tremlett, it had reminded him why he had done medicine – it allowed pure medical care without the managerial and political distraction. He pointed out that local providers could not provide the surgical capacity or the anaesthetic quality that was required for this service.
The vote of thanks was given by Dr John Chambers, President of the LSA, and the meeting concluded at 17.30.