1. Intravenous fluid management for the acutely ill child Michael L. Moritz and Juan C. Ayus. Current Opinion in Pediatrics. 2011; 23:186–193
This review article outlines the principles of prescribing intravenous fluids to acutely ill children.
Hyponatraemia is the most common electrolyte abnormality affecting 25 % of hospitalized children. Hyponatraemia is largely an iatrogenic complication associated with the routine use of hypotonic intravenous fluids. It can result in hyponatraemic encephalopathy and death. There are a number of non-osmotic and non-hemodynamic stimuli for ADH release. These include pneumonia, bronchiolitis, asthma, IPPV, CNS infections and head trauma. Children are at particular risk of iatrogenic hyponatraemia in the post operative period. This is because there are a number of other non osmotic stimuli for ADH release. These include the post-operative state, stress, pain, nausea and vomiting and hypoxia. Hospital acquired hyponatraemia has an incidence of 30 % in postoperative children and almost half of reported cases of hyponatraemic encephalopathy occurs in post operative children. The use of hypotonic solutions is the main factor contributing to hyponatraemia.
Take Home Message
This review concludes that hypotonic fluids should not be routinely administered to hospitalized children as the majority have underlying stimuli for ADH production and are therefore at risk of hyponatraemia. This review concludes that 0.9% NaCl is the most physiologic solution and effectively prevents hyponatraemia. No single fluid rate or regime is appropriate for all patients and indeed a subgroup of patients may even require sodium restriction. Children on intravenous fluid therapy should have their clinical fluid status reviewed regularly. Serum electrolytes should be checked daily and fluid prescriptions should be reviewed daily.
2. A comparison of GlideScope videolaryngoscopy and direct laryngoscopy for nasotracheal intubation in children Hyun-Jung Kim et al. Pediatric Anesthesia 21 (2011) 417–421.
This study compares use of the GlideScope videolaryngoscope and direct laryngoscopy for nasal intubation in children. 80 children under ten having elective dental or facial surgery requiring a nasal tube were enrolled. Children with potential difficult airways were not included with the study limited to patients of Cormack and Lehane grade 1 or 2. The trial found that there were no significant differences in glottic view, frequency of use of Magill forceps or degree of difficulty of intubation between the groups. However, there was a shorter time to intubation in the direct laryngoscopy group. The authors suggest that this may be due to lack of experience with the GlideScope videolarygoscope for this indication. They found that for the initial 20 patients the time to intubation was greater for the GV group but for the latter 20 patients, there was no difference between groups indicating a learning curve effect. There were two failures in the GV group. Difficulties were due to limited space in the mouth for manipulation of Magill forceps and a poor view caused by blood in the airway. Difficulties were also encountered using suction to clear blood, again because of limited space. In their discussion, the authors compare their findings in adult population to the current findings in children. They found that whilst in adults where the GV was used for nasotracheal intubation, the Magills forceps were not necessary. In children, the Magill forceps were required for most children in the DL and GV groups. They attribute this finding to the differing anatomy in children.
Take Home Message
Whilst videolaryngoscopes have become a part of difficult airway management in adult anaesthesia, this has not occurred in paediatric anaesthesia. This is in part because many of these new devices have not been available in paediatric sizes. Studies involving their use in children are limited and most have not dealt with the paediatric difficult airway. It is clear that the different airway anatomy in children has an impact on the usefulness of these devices when compared to adults. In addition, the paediatric airway is more susceptible to damage during their use and in particular during the learning curve phase. It seems to me unlikely that any single device will prove useful for all paediatric patients from neonates to teenagers.
3. Towards evidence-based pharmacotherapy in children. EM Kemper et al. Pediatric Anesthesia 21 (2011) 183–189.
This review article outlines the barriers to evidence-based pharmacotherapy in paediatric practice. It outlines the risks associated with off label use of drugs in paediatrics. The authors provide a framework for legislative change, improvements in clinical research and improvements in adverse drug reaction monitoring. These changes, they suggest, are necessary in order to improve the quality of evidence and improve safety.
The paediatric population is heterogenous in terms of size, body compartment composition, and organ function. The pharmacokinetics and pharmacodynamics of drugs administered by all routes is potentially different, depending on the age of the child. Because of these differences, children are considered a vulnerable group when it comes to patient safety. In spite of this about 70 % of drugs used in paediatric practice are either unlicensed or off-label. The percentage may reach 80 - 90 % in neonates. According to this review, studies have suggested a 2 - 5 fold increase in the risk of adverse drug reactions when drugs are administered to children on this basis.
Clinical trials in children are not being conducted . The authors list current barriers to paediatric research. These include financing, political, legal and ethical concerns. Clinical trials in paediatrics are further complicated by the need to investigate different age groups, different formulation requirements, small patient numbers and convincing parents of the importance of paediatric research. The European Union has put in place incentives (such as patent extensions) to encourage this. Legislation exists in the United States and Europe which aims to improve patient care by encouraging paediatric research. Full reporting of adverse drug reactions is necessary to improve the situation by providing accurate information on adverse drug reaction. The authors recommend that all future paediatric clinical trials have a safety monitoring committee.
4. Propofol for procedural sedation/anaesthesia in neonates (Review) Shah PS, Shah VS. Cochrane Database of Systematic Reviews 2011, Issue 3. Art. No.: CD007248.
This systematic Cochrane review aims to determine the safety and efficacy of propofol for sedation and anaesthesia in neonates undergoing procedures. Only one unblinded randomized controlled trial was eligible for inclusion in the review. This study looked at propofol vs morphine-atropine-suxamethonium for intubation and included 63 patients. The trial showed a reduction in preparation time, procedure time and post-procedural recovery. There was no increase in side effects associated with propofol. However, the review concludes that the numbers are too small and not all adverse effects were sought. There are two ongoing studies. One compares propofol to sevoflurane and the other compares propofol/remifentanil to midazolam/remifentanil.
Take Home Message
There is very little evidence examining the use of propofol in neonates. According to this review, no practice recommendations can be made based on the available evidence. The review emphasizes cautious use of propofol in neonates due to reduced clearance as a result of age-dependent maturation of hepatic glucoronidation. Repeated boluses or continuous infusion of propofol is discouraged in the first week after birth.
5. Does an objective system-based approach improve assessment of perioperative risk in children? A preliminary evaluation of the ‘NARCO’ S. Malviya. British Journal of Anaesthesia 106 (3): 352–8 (2011).
There is little data examining the use of the ASA-PS in children. The authors have devised a system based tool, the NARCO (Neurological, Airway, Respiratory, Cardiovascular and Other), specifically for children. This paper compares the reliability and validity of the ASA physical status score (ASA-PS), the NARCO and a grading of surgical severity (SS).
Six paediatric anaesthetists rated both the NARCO-SS and ASA-PS for content validity. A cohort of 340 consecutive paediatric patients who underwent general anaesthesia were selected. Identifiers and ASA classifications were removed. Complete pre-anaesthetic assessment, preoperative surgical history and physical examination details were given to 3 paediatric anaesthetists not involved in their care. Each anaesthetist independently assigned NARCO-SS score and ASA-PS scores. Test re-test reliability was assessed re-assigning a selection of patients 3 months later. The study found that both NARCO and ASA-PS were valid tools to use in assessing perioperative risk in children. They also found that there was an improvement in correlation when these scores were combined with the surgical severity score. Inter rater reliability was found to be acceptable for the ASA-PS.
Take Home Message
The authors point out that the ASA was originally designed to assess preoperative health status. It was not originally designed to assess perioperative risk as it does not take into account the nature of surgery and its likely impact. It has been modified and its use has been expanded to assess perioperative risk, to guide billing, for research and in planning/allocation of resources. It is interesting to find that the ASA-PS was valid and reliable even though it is not specific to children and is not system based. High ASA-PS scores and NARCO-SS scores were found to be predictive of escalation of care, hospital admission, length of stay and prevalence of adverse events and mortality.
6. Equipment and monitoring – what is in the future to improve safety? S Campbell, G Wilson T Engelhardt. Pediatric Anesthesia 2011,
This review looks at advances in existing equipment and monitoring, new equipment and monitoring and future advances in equipment and monitoring. It discusses the paediatric applications of new technology and evidence surrounding existing controversies. This review focuses on improved safety and outcomes in pediatric anaesthesia.
Equipment Covered
1. Cuffed Tracheal Tubes
2. New Laryngoscopes
3. Ventilation and Ventilation Modes
4. Ultrasound for regional and vascular access
5. Vascular access - vein viewer, statlock (suture free fixation), safety cannulae
6. Advances in pulse oximetry
7. Continuous non invasive haemoglobin
8. Near infrared spectroscopy (NIRS)
9. Neuromonitoring (Brainstem auditory evoked potentials, BIS and other EEG devices)
10. Cardiac Out put measurements
Findings of Note Include:
Cuffed tracheal Tubes
- Prospective randomized controlled trial by the Europen Paediatric Endotracheal Intubation study Group showed that the use of Microcuff ETT is effective and safe in neonates and young children but that its routine use cannot be justified.
- Indications for use include a need to minimise ETT changes, when it is essential to minimise leak and when greater protection from soiling of the airway is required.
- The modern paediatric Microcuff is a purpose designed high volume low pressure cuff which provides an effective seal at less than 20 cm H2O. The study only looked at microcuff ETT with pressures kept below 20 cm H2O
Airway - New Laryngoscopes
- Videolaryngoscopes and optical laryngoscopes are available in paediatric and neonatal sizes. However, their usefulness in the peadiatric setting is unclear with large trials comparing the devices lacking.
- There is a learning curve required for each new device.
- There is the potential for significant damage to the small and sensitive paediatric airway.
Ultrasound Guided Venous Access.
- US guided CVC access is associated with less number of attempts, reduces number of sites attempted and reduces the number of inadvertent arterial punctures.
- Non use of ultrasound for central venous and arterial catheter placement is becoming more difficult to justify.
Ultrasound for Regional Anaesthesia
- Paediatric regional anaesthesia is usually performed in anaesthetised patients and therefore techniques that improve margin of safety are important.
- Ultrasound imaging for epidurals is effective in children who have superficial epidural spaces and less ossification.
- Ultrasound takes time to learn and requires additional assistance to perform, it has been shown to shorten onset time, performance time and the number of punctures for peripheral nerve blocks.
- Ultrasound has been shown to reduce the volume of local anaesthetic needed to achieve effective block.
- No data on neurological complications following regional anaesthesia are available in pediatric anesthesia.
Continuous noninvasive hemoglobin
- measures Haemoglobin, methaemoglobim, carboxyhaemoglobin and oxygen content.
- No data to indicate whether this improves outcomes in paediatrics.
Near Infrared Spectroscopy (NIRS)
- Measures cerebral oxygenation. Real time window
- Assists in detection of low flow states.
- Improved outcome in cardiac surgery
Disclaimer
Reasonable attempts are made to include articles representative of recent publications, but no attempt is made to include every important article. The commentaries and take-home messages are only some of many possible opinions/interpretations from the anaesthesia literature.
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