Preliminary clinical use of a patient-controlled intranasal analgesia (PCINA) device

Intranasal fentanyl: from pharmacokinetics and bioavailability to current treatment applications

Fentanyl, a short-acting synthetic pure opiate, offers an excellent option for the treatment of cancer and chronic pain. While oral administration is not an option, its high potency and lipophilicity have made intranasal administration feasible. Intranasal fentanyl has a bioavailability of 89%, with a short onset of action ( approximately 7 min) and duration times ( approximately 1 h). It bypasses the oral/gastrointestinal route, delivers the analgesic dose in a volume of 150 microl that can be adequately absorbed and, with a pH of 6.4, avoids local irritation. Intranasal fentanyl has been investigated to assess its potential as a well-tolerated acute postoperative breakthrough pain relief medication. It has been shown to be superior to oral transmucosal fentanyl for the treatment of cancer breakthrough pain. Similar analgesic effects to fentanyl or morphine intravenously and orally, with a similar safety profile, have been reported for postoperative or acute pain treatment of children and adults in the prehospital and hospital settings.

Intranasal sufentanil for cancer-associated breakthrough pain

The objective of this study was to demonstrate the efficacy, safety and patient acceptability of the use of intranasal sufentanil for cancer-associated breakthrough pain. This was a prospective, open label, observational study of patients in three inpatient palliative care units in Australia. Patients on opioids with cancer-associated breakthrough pain and clinical evidence of opioid responsiveness to their breakthrough pain were given intranasal (IN) Sufentanil via a GO Medical patient controlled IN analgesia device. The main outcome measures were pain scores, need to revert to previous breakthrough opioid after 30 min, number of patients who chose to continue using IN sufentanil, and adverse effects. There were 64 episodes of use of IN sufentanil for breakthrough pain in 30 patients. There was a significant reduction in pain scores at 15 (P < 0.0001) and 30 min (P < 0.0001). In only 4/64 (6%) episodes of breakthrough pain did the participants choose to revert to their prestudy breakthrough medication. Twenty-three patients (77%) rated IN sufentanil as better than their prestudy breakthrough medication. The incidence of adverse effects was low and most were mild. Our study showed that IN sufentanil can provide relatively rapid onset, intense but relatively short lasting analgesia and in the palliative care setting it is an effective, practical, and safe option for breakthrough pain.

A randomized controlled trial comparing intranasal fentanyl to intravenous morphine for managing acute pain in children in the emergency department

STUDY OBJECTIVE

We compare the efficacy of intranasal fentanyl versus intravenous morphine in a pediatric population presenting to an emergency department (ED) with acute long-bone fractures.

METHODS

We conducted a prospective, randomized, double-blind, placebo-controlled, clinical trial in a tertiary pediatric ED between September 2001 and January 2005. A convenience sample of children aged 7 to 15 years with clinically deformed closed long-bone fractures was included to receive either active intravenous morphine (10 mg/mL) and intranasal placebo or active intranasal concentrated fentanyl (150 microg/mL) and intravenous placebo. Exclusion criteria were narcotic analgesia within 4 hours of arrival, significant head injury, allergy to opiates, nasal blockage, or inability to perform pain scoring. Pain scores were rated by using a 100-mm visual analog scale at 0, 5, 10, 20, and 30 minutes. Routine clinical observations and adverse events were recorded.

RESULTS

Sixty-seven children were enrolled (mean age 10.9 years [SD 2.4]). Fractures were radius or ulna 53 (79.1%), humerus 9 (13.4%), tibia or fibula 4 (6.0%), and femur 1 (1.5%). Thirty-four children received intravenous (i.v.) morphine and 33 received intranasal fentanyl. Statistically significant differences in visual analog scale scores were not observed between the 2 treatment arms either preanalgesia or at 5, 10, 20, or 30 minutes postanalgesia (P=.333). At 10 minutes, the difference in mean visual analog scale between the morphine and fentanyl groups was -5 mm (95% confidence interval -16 to 7 mm). Reductions in combined pain scores occurred at 5 minutes (20 mm; P=.000), 10 minutes (4 mm; P=.012), and 20 minutes (8 mm; P=.000) postanalgesia. The mean total INF dose was 1.7 microg/kg, and the mean total i.v. morphine dose was 0.11 mg/kg. There were no serious adverse events.

CONCLUSION

Intranasal fentanyl delivered as 150 microg/mL at a dose of 1.7 microg/kg was shown to be an effective analgesic in children aged 7 to 15 years presenting to an ED with an acute fracture when compared to intravenous morphine at 0.1 mg/kg.

Intranasal fentanyl is an equivalent analgesic to oral morphine in paediatric burns patients for dressing changes: a randomised double blind crossover study

INTRODUCTION

The ideal analgesic agent for burns wound dressings in paediatric patients would be one that is easy to administer, well tolerated, and produces rapid onset of analgesia with a short duration of action and minimal side-effects to allow rapid resumption of activities and oral intake. We compared our current treatment of oral morphine to intranasal fentanyl in an attempt to find an agent closer to the ideal.

METHODS

A randomised double blind two-treatment crossover study comparing intranasal administration of fentanyl (INF) to orally administered morphine (OM). Children with burn injury aged up to 15 years and weighing 10-75 kg were included. Primary end-point was pain scores. Secondary end-points were time to resumption of age-appropriate activities, time to resumption of fluid intake, sedation and cooperation. Routine observations and vital signs were also recorded.

RESULTS

Twenty-four patients were studied with a median age of 4.5 years (interquartile range 1.8-9.0 years) and a median weight of 18.4 kg (interquartile range 12.9-33.2kg). Mean pain difference scores (OM-INF) ranged from -0.500 (95% CI=-1.653 to 0.653) at baseline to -0.625 (05% CI=-1.863 to 0.613) for a retrospective rating of worst pain experienced during the dressing procedure. All measurements were within a pre-defined range of equivalent efficacy. The median time to resumption of fluid intake was 108 min (range 44-175 min) with OM and 140 min (range 60-210 min) with INF. These differences were not statistically significant. Fewer patients experienced mild side-effects with INF compared to OM (n=5 versus n=10). No patients experienced depressed respirations or oxygen saturations.

SUMMARY

Intranasal fentanyl was shown to be equivalent to oral morphine in the provision of analgesia for burn wound dressing changes in this cohort of paediatric patients. It was concluded that intranasal fentanyl is a suitable analgesic agent for use in paediatric burns dressing changes either by itself or in combination with oral morphine as a top up titratable agent.

A randomised crossover trial of patient controlled intranasal fentanyl and oral morphine for procedural wound care in adult patients with burns

This study sought to compare the analgesic efficacy and safety of patient controlled intra-nasal (PCIN) fentanyl with oral morphine for procedural wound care in burns patients. A randomised double-blind placebo controlled, two period, two-treatment crossover trial was conducted within the Burns Unit of a major teaching hospital in Perth, Western Australia. Patients requiring identical wound care procedures on two consecutive mornings (and not prescribed intravenous analgesia) were randomised to receive either PCIN fentanyl with oral placebo or oral morphine with intranasal placebo on 1 day, followed by the alternate active drug on the following day. Twenty-six patients (22 males), aged between 18 and 69 years (35.5 +/- 12.4 years), with total body surface burns (TBSA) range 1-25% (6.9 +/- 4.5), indicated their level of pain on a 10 point (0-10) numeric scale at various time periods before, during and after the procedure. A mean total dose of 1.48 +/- 0.57 microg/kg of PCIN fentanyl and 0.35 +/- 0.12 mg/kg of oral morphine was administered. No statistically significant difference was found between the pain scores recorded for patients during the procedure with PCIN fentanyl compared to that with oral morphine (mean difference = -0.75, 95% CI = -1.97 to 0.47, P = 0.22). Two patients experienced hypotension during the procedure--both had received active oral morphine. No patients experienced respiratory depression or a significant drop in oxygen saturation. There were four episodes (in three patients) where 'rescue analgesia' for severe pain was required--two episodes involving oral morphine and two involving PCIN fentanyl. It was concluded that PCIN fentanyl is similar in efficacy and safety to oral morphine for relief of procedural wound care pain in burns patients.

A new formulation of nasal fentanyl spray for postoperative analgesia: a pilot study

Twenty-four gynaecological patients receiving postoperative patient-controlled analgesia were enrolled in an open cross-over pilot study evaluating two new formulations of nasal fentanyl spray. The primary outcome was the bioavailability of nasal fentanyl in comparison with intravenous fentanyl. This manuscript describes the clinical outcomes of quality of postoperative analgesia and patient acceptability. There were 21 complete data sets for both sequences of the cross-over design. In randomised order, patients received approximately 50 microg of fentanyl in a single dose by intranasal and intravenous administration, but separated by at least 2 h. Analgesia was of rapid onset (within 5 min) and similar quality. There was no significant difference in side-effects. Four patients experienced mild nasal stinging and although 10 (42%) preferred intravenous administration, seven (29%) preferred intranasal and six (25%) had no preference. We conclude that these formulations of fentanyl, delivered as nasal spray, have potential clinical utility.

Nasal administration of opioids for pain management in adults

BACKGROUND

Nasal administration of opioids may be an alternative route to intravenous, subcutaneous, oral transmucosal, oral or rectal administration in some patients. Key features may be self-administration, combined with rapid onset of action. The aim of this paper is to evaluate the present base of knowledge on this topic.

METHODS

The review is based on human studies found in Medline or in the reference list of these papers. The physiology of the nasal mucosa and some pharmaceutical aspects of nasal administration are described. The design of each study is described, but not systematically evaluated.

RESULTS

Pharmacokinetic studies in volunteers are reported for fentanyl, alfentanil, sufentanil, butorphanol, oxycodone and buprenorphine. Mean times for achieving maximum serum concentrations vary from 5 to 50 min, while mean figures for bioavailability vary from 46 to 71%. Fentanyl, pethidine and butorphanol have been studied for postoperative pain. Mean onset times vary from 12 to 22 min and times to peak effect from 24 to 60 min. There is considerable interindividual variation in pharmacokinetics and clinical outcome. This may partly be due to lack of optimization of nasal formulations. Patient-controlled nasal analgesia is an effective alternative to intravenous PCA. Adverse effects are mainly those related to the opioids themselves, rather than to nasal administration. Some experience with nasal opioids in outpatients and for chronic pain has also been reported.

CONCLUSION

Nasal administration of opioids has promising features, but is still in its infancy. Adequately designed clinical studies are needed. Improvements of nasal sprayer devices and opioid formulations may improve clinical outcome.

Patient-controlled analgesia: an appropriate method of pain control in children

Patient-controlled analgesia (PCA) is an analgesic technique originally used in adults but now with an established role in paediatric practice. It is well tolerated in children as young as 5 years and has uses in postoperative pain as well as burns, oncology and palliative care. The use of background infusions is more frequent in children and improves efficacy; however, it may increase the occurrence of adverse effects such as nausea and respiratory depression. Monitoring involves measurement of respiratory rate, level of sedation and oxygen saturation. Efficacy is assessed by self-reporting, visual analogue scales, faces pain scales and usage patterns. This is optimally performed both at rest and on movement. The selection of opioid used in PCA is perhaps less critical than the appropriate selection of parameters such as bolus dose, lockout and background infusion rate. Moreover, opioid choice may be based on adverse effect profile rather than efficacy. The concept of PCA continues to be developed in children, with patient-controlled epidural analgesia, subcutaneous PCA and intranasal PCA being recent extensions of the method. There may also be a role for patient-controlled sedation. PCA, when used with adequate monitoring, is a well tolerated technique with high patient and staff acceptance. It can now be regarded as a standard for the delivery of postoperative analgesia in children aged >5 years.

Intravenous ketamine plus midazolam is superior to intranasal midazolam for emergency paediatric procedural sedation

OBJECTIVES

This study compared intranasal midazolam (INM) with a combination of intravenous ketamine and intravenous midazolam (IVKM) for sedation of children requiring minor procedures in the emergency department.

METHOD

A single blinded randomised clinical trial was conducted in the emergency department of a major urban paediatric hospital. Subjects requiring sedation for minor procedures were randomised to receive either INM (0.4 mg/kg) or intravenous ketamine (1 mg/kg) plus intravenous midazolam (0.1 mg/kg). Physiological variables and two independent measures of sedation (Sedation Score and Visual Analogue Sedation Scale) were recorded before sedation and at regular intervals during the procedure and recovery period. Times to adequate level of sedation and to discharge were compared.

RESULTS

Fifty three patients were enrolled over a 10 month period. Sedation was sufficient to complete the procedures in all children receiving IVKM and in 24 of the 26 receiving INM. Onset of sedation was an average of 5.3 minutes quicker with IVKM than with INM (95%CI 3.2, 7.4 minutes, p<0.001). Children given INM were discharged an average of 19 minutes earlier than those given IVKM (95%CI 4, 33 minutes, p=0.02). Mean Sedation Scores and Visual Analogue Sedation Scale scores for the 30 minutes after drug administration were significantly better in children given IVKM compared with INM (2.4 and 1.8 versus 3.5 and 3.8, respectively). Both doctors and parents were more satisfied with sedation by intravenous ketamine and midazolam.

CONCLUSIONS

Intravenous ketamine plus midazolam used in an appropriate setting by experienced personnel provides an excellent means of achieving sedation suitable for most non-painful minor procedures for children in the emergency department. This combination is superior to INM in terms of speed of onset and consistency of effect. INM delivered via aerosol spray has a more variable effect but may still be adequate for the completion of many of these procedures.

An assessment of the safety, efficacy, and acceptability of intranasal fentanyl citrate in the management of cancer-related breakthrough pain: a pilot study

The effects of intranasal fentanyl citrate (INFC) were assessed in 12 hospice inpatients with cancer-related breakthrough pain. Patients received 20 microg of fentanyl citrate and were asked to rate their pain using a visual analogue scale (VAS) before INFC, then after 3, 5, 10, 15, 30, 45, and 60 minutes. Eight patients (66%) had reductions in pain scores, four within 5 minutes and seven within 10 minutes of taking INFC. Ratings for INFC were very good (5 = 42%), good (3 = 25%), moderate (1 = 8%), and bad (3 = 25%). In comparison to oral morphine, INFC was better (6 = 50%), the same (3 = 25%), or worse (3 = 25%). Nine patients (75%) said they would continue to use INFC. Of the three patients who did not experience a positive result, two were taking relatively higher baseline opioid doses and one was found to have a fracture. No systemic adverse events were noted; two patients reported nasal itching or discomfort on first use that disappeared with repeated use. Intranasal fentanyl citrate appears safe and well tolerated by these patients. Randomized placebo-controlled and dose-ranging studies are required to confirm these findings.

In the arms of Morpheus the development of morphine for postoperative pain relief

PURPOSE

To analyse the historical development of morphine for postoperative analgesia and how this development was shaped by the evolution of anesthetic techniques.

METHODS

After a systematic review of the literature, information was gathered from primary sources.

PRINCIPAL FINDINGS

In ancient medicine, some plant derivatives were used to alleviate pain including: alcohol, cannabis, mandrake, and opium. Over the past two centuries, opium and its derivatives have become the most widely used analgesics for severe pain. Before the development of general anesthesia, surgery was only performed out of extreme necessity. It is probable that an analgesic such as opium would have been given following surgery although its use may not have been recorded. The first description of postoperative opium was by James Moore in 1784. Morphine was isolated from opium by Friedrich Serturner in 1805. However, it was not until the development of the hypodermic needle and syringe nearly 50 yr later that the use of morphine became widespread. Over the last century, various delivery systems for morphine have been developed including subarachanoid and epidural injection, and more recently patient-controlled intravenous, epidural and intranasal analgesia. In addition, many new opioids have been synthesized.

CONCLUSION

Since its isolation from opium almost 200 yr ago, morphine remains the most widely used analgesic and the standard against which all new opioids for postoperative pain relief are compared.