Ketamine Sedation in Children

Overview

Ketamine is capable of producing a trance-like dissociative state characterised by profound analgesia and amnesia, with retention of protective airway reflexes, spontaneous respiration and cardiopulmonary stability.

As a result, it has an excellent track record in procedural sedation for children in emergency medicine internationally dating from 1998 [1]. It provides more reliable sedation than benzodiazepine/opioid combinations. More importantly, it appears safer [2].

A CEM guideline for its IM use has existed since 2003. In September 2009 the College published Ketamine Sedation of Children in Emergency Departments [3], for either IM or IV administration.

This session is based upon College guidelines.

Indications

Ketamine sedation is ideal for short, painful or frightening procedures. In no particular order, it may facilitate:

• Suturing lacerations under local anaesthesia
• Removal of foreign bodies
• Orthopaedic procedures including joint relocation, fracture manipulation or joint aspiration

Two important points to consider before opting for ketamine sedation:

1. Ensure that the child has received appropriate analgesia. This might include intranasal opiates, such as fentanyl or diamorphine, paracetamol, ibuprofen or all three as appropriate
2. Have alternative strategies been considered e.g. Entonox

Papers comparing Entonox 50:50 with 70:30 showed higher rates of desaturation in the nitrous rich blend with no additional analgesic or anxiolytic benefit. In practice, non 50:50 blends in the UK ED will require an anaesthetic machine, and are unlikely.

Other issues:

• Do you have some experience in distraction techniques?

Get the help of an experienced nurse or play specialist and encourage parental co-operation. Some well described examples include: music [4], hypnosis [5], confusing tactile stimuli [6] and blowing away pain [7]. A current tactic is to use a DVD, selecting suitable material for each age group (know your current TV programmes ). Information regarding the entire procedure can also be related to the smaller child in the form of a story [8].

• Is there a role for topical local anaesthetic agents for wound toilet, and steristrips or glue for wound closure? You might diminish the pain on infiltration of (warmed) local anaesthetics by injecting slowly and using a fine gauge needle
• Are you familiar with the pearls of foreign body removal that may obviate the need for sedation (the magic kiss for example)?
• Is the laceration too complex for brief (< 20 minute) repair?
• Might the orthopaedic procedure be better performed with image intensifier support in theatre?

Learning Bite

Ensure that your child has received appropriate analgesia before considering sedation. Carefully consider alternative strategies to sedation in general.

Contra-indications

1. Any child <24 months; younger than <12 months if you follow the College guideline to the letter: 12-24 months by expert staff only. The younger the child, the more likely airway complications, including laryngospasm
2. The childs fasting status: whilst no evidence that complications are reduced in fasted children, common sense and anaesthetic practice dictates that you consider the urgency of the procedure in non-fasted children. Can the procedure wait? Weigh the balance: lacerations, foreign bodies and most fractures typically can; joint dislocations and badly angulated fractures typically cannot the College guideline allows you to proceed in these cases
3. Coughs and colds: ketamine increases secretions in all children (hence the former debate regarding the use of prophylactic atropine). Children with an URTI have increased secretions before you start. Excess secretions may trigger laryngospasm
4. Significant learning difficulties: the dissociative state induced by ketamine may not be well experienced by these children

Heres the complete list of contraindications from the College guideline:

• Age less than 12 months
• Active respiratory infection, active asthma
• Unstable or abnormal airway. Tracheal surgery or stenosis.
• Active upper or lower respiratory tract infection
• Proposed procedure within the mouth or pharynx
• Patients with severe psychological problems such as cognitive or motor delay or severe behavioural problems
• Significant cardiac disease
• Recent significant head injury or reduced level of consciousness
• Intracranial hypertension with CSF obstruction
• Intra-ocular pathology
• Previous psychotic illness
• Uncontrolled epilepsy
• Hyperthyroidism or thyroid medication
• Porphyria
• Prior adverse reaction to ketamine

A relative contra-indication that might result in a child receiving in-patient general anaesthesia is commonly a lack of adequate ED resources: typically because of excess departmental workload.

Learning Bite

• The College guideline allows you to proceed with ketamine sedation for non-fasted children if the clinical need dictates urgent action.
• Specific contraindications to ketamine sedation include infants and children with URTIs or significant learning difficulties.
• Simple airway manoeuvres will counter most airway problems. The need for suxamethonium in response to airway difficulty is rare, 0.02%: 1 incident in 5000 sedations.

Consent

Seek informed consent from the parent/guardian and older child, including in your discussion potential risks vs benefits, adverse events and alternative options (as previously covered in this session). This is good medical practice. The combined RCoA and RCEM guideline on Adult Sedation specifically advocates written consent specifically for the process of sedation, in addition to consent for any procedure undertaken. Whilst this is best practice, verbal consent can be used where the clinical situation demands expediency. The RCEM paediatric guideline lists the known risks as mild agitation (20%), moderate/severe agitation (1.5%), rash (10%), vomiting (7%), transient clonic movements (5%), and airway problems (1%)

The College guideline offers you the choice of either IM or IV administration. Sedation using the IV route is preferable where possible. The use of topical anaesthetic agents such as EMLA and Ametop to provide analgesia for IV access is encouraged if time allows; depending on the agent used this may take up to 60 minutes

Key adverse clinical effects that you should consider discussing are:

• Vomiting 10%
• Laryngospasm 0.3%
• Need for general anaesthetic (including suxamethonium) 0.02%

Written consent for both the sedation and the procedure is advised.

Stop! Reconsider:

• Is ketamine sedation the right answer for the child’s complaint?
• Is the child adequately analgesed?
• Can the operator complete the procedure within 20 minutes?

Weight of child

Weigh the child when possible. If not, calculate the weight as per the standard formula: weight (kg) = (age + 4) x 2. Be prepared to ‘adjust’ when common sense suggests.

IM or IV administration

The College guideline offers you the choice of either IM or IV administration. The use of topical anaesthetic agents is encouraged if time allows, remembering they take 60 minutes or so for effect in countering the pain of IV cannulation.

My own department’s approach is for IV ketamine, reserving the IM route for when IV cannulation has failed, or is predictably difficult. We opt for cannulation in the child friendly cubical/room to which they’ve become accustomed – using distraction techniques previously described. We then move parent and child to the ‘special’ room – the paediatric resuscitation bay equipped with a ceiling mounted DVD. We encourage younger children to sit on mum or dad’s lap. That way, there is hopefully a distinction from the child’s perspective, of the room of ‘pain’ – or at least where things haven’t been particularly great – and the DVD room where there is no more pain. Get it?

The room

A dedicated, isolated room with full paediatric resuscitation facilities is the ideal. Ensure that you are familiar with the environment and have checked that the child specific equipment is available and functions beforehand. This includes rescue airway equipment. Establish the child specific dose of atropine and suxamethonium too and ensure these are trolleyside. ECG/NIBP/RR/sats monitoring and supplemental oxygen are all advised. You will need a team of three – the ‘sedator’, the ‘operator’ and a registered nurse.

Dosage

The IV dose is 1 mg/kg slowly – no less than a minute, so as to avoid apnoea. If the child isn’t engaged in the DVD, do encourage some happy chitchat between parent and child. A book or toy may substitute for a DVD.

Within 60 seconds you should sense that the child becomes vacant, demonstrating occasional nystagmus. You may wish to invite mum or dad to leave at this stage. Your operating colleague may now proceed. Infiltrative local is still advised where indicated, despite the apparent sedation.

Supplemental (slow) IV doses of 0.5 mg/kg may be required should you deem the level of sedation inadequate, or if the procedure is prolonged.

Your nursing colleague should record observations regularly – every five minutes until the procedure is complete in the my department.

Alternative strategy

An alternative strategy is 2.5 mg/kg IM injection in the lateral aspect of a thigh (prepared with topical local anaesthetic if time allows).  Expect 5-8 minutes for clinical effect. Use top-up doses of 1 mg/kg IM as required.

Red flag

Note that three different vials of ketamine are available: 10, 50 and 100 mg/ml solutions. You will need the 100 mg/ml vial in order to minimise the IM volume; the 10 mg/ml preparation is better suited for accurate IV dosing. We see no reason to stock a 50 mg/ml preparation.

Check the drug preparation carefully to avoid a drug error. My own department keeps the IM and IV vials separately with brightly coloured laminates attached to the inside of the locked cupboard.

Learning bite

Slow IV ketamine administration, no less than 60 seconds.
ECG, NIBP, RR, sats monitoring and supplemental oxygen are all advised.

College of Emergency Medicine post-procedure advice:

• The child should recover in a quiet, observed and monitored area under the continuous observation of a trained member of staff. Recovery should be complete between 60 and 120 minutes, depending on the dose and route used
• The child can be safely discharged once they are able to ambulate and vocalise/converse at pre-sedation levels. An advice sheet should be given to the parent or guardian advising rest, quiet and supervised activity for the remainder of that day. The child should not eat or drink for two hours after discharge because of the risk of nausea and vomiting

Downloadable appendices exist:

Appendix 3 example ketamine information sheets of parents: part 3 after you go home

Appendix 4 example discharge advice to parents

So is 1:1 nursing in an area replete with paediatric resuscitation facilities required until discharge? Or more simply put, when can the child leave resus?

A useful analysis of the timing of adverse events in ED sedation exists; 353 of the 1,367 children in the study received ketamine [10]. Three pertinent findings were:

• Only 8% of adverse events occurred after the procedure
• Median time to serious adverse event was 2 mins after the last sedative dose
• No primary adverse event after 25 mins

Local guidance:

My own department policy is to move the child to a dedicated paediatric observation area with oxygen saturation monitoring only, as soon as the child shows signs of recovery i.e. starts talking to mum or dad.

Learning Bite

A primary adverse event arising later than 30 minutes following the last ketamine dose is exceptional.

Governance issues include:

• Training
• Documentation and audit
• Risk management

Training

The guideline is clear: ketamine should be only used by clinicians experienced in its use and capable of managing any complications, particularly airway obstruction, apnoea and laryngospasm. The doctor managing the ketamine sedation and airway should be suitably trained and experienced in ketamine use, with a full range of advanced airway skills.

Discuss with senior colleagues how you might secure competency; consider specific manikin-based workshops on laryngospasm.

Documentation and audit

A dedicated electronic, password-protected database with mandatory entry for ketamine sedation is probably the key, coupled with timely analysis by a named departmental sedation lead.

Risk management

In the audit process consider:

• Was a specific sedation monitoring chart used?
• Were the indications for ketamine sedation appropriate?
• Were any contra-indications acknowledged?
• What complications arose and how were they managed?

Pre-emptive strategies might also include:

• Ready access to the College guideline
• A dedicated monitoring chart for ketamine sedation
• A system of support for addressing laryngospasm

Selection and storage of ketamine vials (as discussed previously)

Learning Bite

There should be a documentation and audit system in place within a framework of clinical governance.

• Ensure that your child has received appropriate analgesia before considering sedation (Grade D, Level 5)
• Carefully consider alternative strategies to sedation in general (Grade D, Level 5)
• The College guideline allows you to proceed with ketamine sedation for non-fasted children, if the clinical need dictates urgent action (Grade C, Level 4)
• Specific contraindications to ketamine sedation include infants and children with URTIs or significant learning difficulties (Grade C, Level 4)
• Slow IV ketamine administration, no less than 60 seconds (Grade C, Level 4)
• ECG, NIBP, RR, sats monitoring and supplemental oxygen are all advised (Grade C, Level 4)
• Simple airway manoeuvres will counter most airway problems (Grade C, Level 4)
• The need for suxamethonium in response to airway difficulty is rare (Grade C, Level 4)
• A primary adverse event arising later than 30 minutes following the last ketamine dose is exceptional (Grade C, Level 4)
• There should be a documentation and audit system in place within a framework of clinical governance (Grade D, Level 5)

1. Green SM, Rothrock SG, Lynch EL et al. Intramuscular ketamine for pediatric sedation in the emergency department: safety profile in 1,022 cases. Ann Emerg Med 1998;31:688-697.
2. Agrawal D, Manzi SF, Gupta R et al. Preprocedural fasting state and adverse events in children undergoing procedural sedation and analgesia in a paediatric emergency department. Ann Emerg Med Nov 2003;42:636-646.
3. Royal College of Emergency Medicine. Ketamine sedation of children in emergency departments. CEM, 2016. View guideline
4. Menegazzi JJ, Paris PM, Kersteen CH et al. A randomised controlled trial of the use of music during laceration repair. Ann Emerg Med 199:20:348-350.
5. Zelter L, LeBaron S. Hypnosis and non-hypnotic techniques for reduction of pain and anxiety during painful procedures in children and adolescents with cancer. J Paediatrics 1982;101:1032-1035.
6. Kuttner L. Management of young childrens acute pain and anxiety during invasive medical procedures. Paediatrician 1989;16:39-44.
7. French GM, Painter EC, Coury DL. Blowing away shot pain; a technique for pain management during immunisation. Paediatrics 1994;93:384-388.
8. Harrison A. Preparing children for venous blood sampling. Pain 1991;45:299-306.
9. Langston WT, Wathen JE, Roback MG et al. Effect of ondansetron on the incidence of vomiting associated with ketamine sedation in children: a double-blind, randomized, placebo-controlled trial. Ann Emerg Med 2008;52:30-34.
10. Newman DH, Azer MM, Pitetti RD et al. When is a patient safe for discharge after procedural sedation? The timing of adverse effect events in 1,367 paediatric procedural sedations. Ann Emerg Med 2003;42:627-635.
11. Clinical Practice Guideline for Emergency Department Ketamine Dissociative Sedation: 2011 Update Green, Steven M. et al. Annals of Emergency Medicine , Volume 57 , Issue 5 , 449 461
12. Safe Sedation of Adults in the Emergency Department: Report and Recommendations by The Royal College of Anaesthetists and The College of Emergency Medicine Working Party on Sedation, Anaesthesia and Airway Management in the Emergency Department November 2012