A small pilot study on a convenience sample of children presenting to the emergency department with acute limb injury pain evaluated the use of intranasal ketamine(1).
Initial dose averaged 0.84 mg/kg and a third of the patients required a top up dose at 15 minutes, resulting in a total dose of about 1.0 mg/kg to provide adequate analgesia by 30 min for most patients. The authors suggest that this could guide investigators on an appropriate dose of IN ketamine for use in clinical trials.
Adverse events were all transient and mild.
Prior to administration, the ketamine was diluted with saline to a total volume of 0.5 mL and was administered as 0.25 mL per nare using a Mucosal Atomiser Device (MAD, Wolfe Tory Medical, Salt Lake City, UT, USA). According to the protocols in my Service, this device requires 0.1 ml to prime its dead space(2). It is unclear whether this factor may have affected the total dose delivered to the patient in this study.
1. Sub-dissociative dose intranasal ketamine for limb injury pain in children in the emergency department: A pilot study
Emerg Med Australas. 2013 Apr;25(2):161-7
OBJECTIVE: The present study aims to conduct a pilot study examining the effectiveness of intranasal (IN) ketamine as an analgesic for children in the ED.
METHODS: The present study used an observational study on a convenience sample of paediatric ED patients aged 3-13 years, with moderate to severe (≥6/10) pain from isolated limb injury. IN ketamine was administered at enrolment, with a supplementary dose after 15 min, if required. Primary outcome was change in median pain rating at 30 min. Secondary outcomes included change in median pain rating at 60 min, patient/parent satisfaction, need for additional analgesia and adverse events being reported.
RESULTS: For the 28 children included in the primary analysis, median age was 9 years (interquartile range [IQR] 6-10). Twenty-three (82.1%) were male. Eighteen (64%) received only one dose of IN ketamine (mean dose 0.84 mg/kg), whereas 10 (36%) required a second dose at 15 min (mean for second dose 0.54 mg/kg). The total mean dose for all patients was 1.0 mg/kg (95% CI: 0.92-1.14). The median pain rating decreased from 74.5 mm (IQR 60-85) to 30 mm (IQR 12-51.5) at 30 min (P < 0.001, Mann-Whitney). For the 24 children who contributed data at 60 min, the median pain rating was 25 mm (IQR 4-44). Twenty (83%) subjects were satisfied with their analgesia. Eight (33%) were given additional opioid analgesia and the 28 reported adverse events were all transient and mild.
CONCLUSIONS: In this population, an average dose of 1.0 mg/kg IN ketamine provided adequate analgesia by 30 min for most patients
2. Case report: prehospital use of intranasal ketamine for paediatric burn injury
Emerg Med J. 2011 Apr;28(4):328-9
In this study, the administration of an intravenous ketamine formulation to the nasal mucosa of a paediatric burn victim is described in the prehospital environment. Effective analgesia was achieved without the need for vascular or osseous access. Intranasal ketamine has been previously described for chronic pain and anaesthetic premedication. This case highlights its potential as an option for prehospital analgesia.
As well as the benefits of cardiovascular stability, maintenance of cerebral perfusion pressure, possibly lowering ICP and providing other neuroprotective benefits, ketamine may have other advantages. These are reviewed in a British Journal of Anaesthesia article from which I’ve selected those benefits of interest to practitioners of emergency medicine and critical care.
Additional Beneficial Effects of Ketamine
- the dysphoric, or ’emergence’ reactions associated with ketamine may be reduced by pre-administration or co-administration of sedatives, such as benzodiazepines, propofol, dexmedetomidine, or droperidol.
- ketamine potentiates opioid analgesia in multiple settings, reducing opioid total dose and in some groups of patients reducing postoperative desaturation
- ketamine has possible anti-inflammatory effects demonstrated in some types of surgical patients
- ketamine may prevent awareness, recall, or both during general anaesthesia
Ketamine: new uses for an old drug?
Br J Anaesth. 2011 Aug;107(2):123-6
I published a case report in the EMJ highlighting the use of intranasal ketamine in a pre-hospital paediatric burns case.
The lad had nasty scalds but did not need iv fluids and had no other indications for an iv line. The vigorous first aid had rendered him cold and veinless and an intraosseous would have been overkill. Ketamine was perfect for the job and Ambulance Service New South Wales paramedics carry a mucosal atomisation device (MAD) for the administration of i.n. fentanyl. I used the MAD to adminster 0.5 mg/kg ketamine, but there is a dead space in the device (0.1 ml) that probably resulted in actual delivery of 0.25mg/kg. This gave great analgesia and compliance enabling us to painlessly apply polyethylene film to the burns.
I received the following email from TIm Wolfe, the inventor of the MAD nasal (reproduced with permission):
Nice contribution to the literature. There is a lot of interest in IN ketamine in these lower doses to treat pain but not cause sedation. You eluded to the military interest and the hospice interest. I think your insights for EMS are also cutting edge – hopefully this will lead others to design a larger trial.
Tim Wolfe, MD
More information on the use of intranasal medication is available at www.intranasal.net. I have no conflicts of interest to declare.
Case report: prehospital use of intranasal ketamine for paediatric burn injury
Emerg Med J. 2011 Feb 3. [Epub ahead of print]
A poster presentation at the Australasian College of Emergency Medicine’s Annual Scientific Conference in Melbourne in November 2009 reports 100 cases of pre-hospital ketamine use for analgesia by paramedics in New Zealand – reproduced below with permission of the author:
Ketamine is a safe and effective analgesic for pre-hospital paramedic led pain relief
HM Hussey & BC Ellis
Introduction: There have been a number of reports on the use of ketamine by pre-hospital physicians, with many advocating its use as the ideal pre-hospital analgesic and sedative due to its airway and cardiovascular stability. There however is little published on its use by paramedics. This study aims to review its effectiveness and safety when administered pre-hospital by paramedics.
Method: Prospective observational study of 100 consecutive administrations by St Johns ambulance paramedics in 2008–09 using a specifically designed data sheet. Demographic data, adjuvant analgesics used, ketamine dose, pre and post dose pain scores on VNRS and physiological parameters were collected. In addition paramedics and patients completed a satisfaction rating score.
Results: The mean dose of ketamine used was 30.2 mg and the mean improvement in pain was 5.10. Ketamine was used both as a lone agent and with morphine; excellent analgesia was achieved in both groups. The most common reason for use was limb trauma followed by burns and extractions from scene. There were no episodes of hypotension or airway compromise. 15% of patients had an adverse reaction all mild and mostly comprising minor psychotropic effects. The median satisfaction rating for both paramedics and patients was ‘Good’.
Conclusion: These results back the use of Ketamine by St John’s Ambulance paramedics and the authors support its use by other pre-hospital services as a safe and effective analgesic.
Emergency Medicine Australasia 2010;22(S1):A30
London HEMS doctors describe their use of ketamine for pre-hospital analgesia and sedation in 1030 retrospectively reviewed cases, concluding its prehospital use is safe.
Pre-hospital use of ketamine for analgesia and procedural sedation
Emerg Med J. 2009 Jan;26(1):62-4