Does intranasal fentanyl provide efficient analgesia for renal colic in adults?

Introduction Intranasal fentanyl provides rapid and powerful analgesia which is particularly interesting in patients without intravenous access. We propose to use it for analgesia in adults presenting renal colics. Methods A prospective study was conducted from the 2nd January to February 2013 in our emergency department. Patients aged up to 18 years old who presented with renal colic were included in this audit. Patients were excluded if they had loss of consciousness, cognitive impairment, acute or chronic nasal problems. A formal written consent was obtained from patients. The research team was alerted by medical and nursing staff. A member of the research team would check with medical or nursing staff whether administration of Intra nasal (IN) fentanyl was required. It was administered at a pre-calculated dose of 1.5 mg/kg and 50 mg/ml concentration was used. Data was prospectively collected by one of the researchers at various intervals during the patient's presentation and recorded on a pre-formatted data sheet. Pain scores were collected at 5, 15, 30, 45 and 60 minutes following IN fentanyl using a visual analogue scale pain. Observations routinely collected for patients receiving IV opiates and any adverse events were also recorded. Results 23 eligible patientswere enrolled; median age was 51,3years. 47,8% were women and the mean weight was 73 kg. Median dose of IN fentanyl was 106 μg. Two patients have required morphinic analgesia despite having received adapted dose of IN fentanyl. The initial pain scores before IN fentanyl were high with a median of 82,2 mm (59-100). Five minutes after IN fentanyl administration the median pain score dropped to 48mm(36-63) and achieved the lowest score of 8mm(0-22) at 30 min. Pain scores were significantly lower at 5 min (P < 0.001) and at all subsequent time points (P < 0.001). No side effects were recorded. Conclusion Intranasal fentanyl seems to be efficient for analgesia in adult patients with renal colic.


Introduction
Renal colic is an intensely painful condition requiring rapid analgesic treatment. Opioids are commonly used intravenously to provide rapid pain relief. The objective of this study was to determine the analgesic efficacy and safety of intranasal single dose of fentanyl for patients presenting to the emergency department with renal colic.

Methods
A prospective study of patients presenting with renal colic was conducted in the emergency department of the military hospital of instruction Mohammed V Rabat where an annual census of 30000 attendances are recorded. Enrollments were made from 2nd January 2013 to February 2013. Adults aged more than 18 years with acute flank pain due to renal colic were included in the study.
Exclusion criteria were known allergy, contraindication to morphine, or any opioid analgesic; hemodynamic instability; fever (temperature ≥38°C (100.4°F'>100.4°F)); evidence of peritoneal inflammation; documented or suspected pregnancy; known or suspected aortic dissection or aneurysm; use of any analgesic treatment within 6 hours before presentation to the Emergency Department; or previous study enrollment. Patients with known renal, pulmonary, cardiac, or hepatic failure, as well as those with renal transplantation, were also excluded. Patients were enrolled 24 hours a day and 7 days a week during the study period. Study eligibility was confirmed by a senior emergency medicine resident. Mean respiratory rate at baseline was 18 (16-24), at 15 min it was 15 (12-18) and remained stable.

Discussion
Intranasal opioid administration has been studied widely in postoperative patients [1,2] and burn patients [3,4]. It has been also compared to intravenous morphine in pediatrics patients. In fact, an IV narcotic would be likely to be superior to an intranasal narcotic at 5 minutes because of the slight delay in absorption of intranasal fentanyl in comparison to IV administration of morphine.
Intranasal fentanyl has been shown to have therapeutic serum levels in 2 minutes, reflecting the good venous outflow of nasal mucosa and bypassing the liver, avoiding hepatic first passage metabolism [5]. In the clinical setting, intranasal fentanyl can be administered promptly into the nasal cavity without the delays Page number not for citation purposes 3 inherent in placing an IV. This mean of fentanyl administration could be part of the triage assessment by nursing staff in an effort to reduce "time to analgesia". There were no significant adverse drug effects in our study. These findings were similar to that of other studies, one of them, a randomized, double blinded, placebocontrolled study showed that Intranasal fentanyl provided analgesia equivalent to that of IV morphine for children aged 7 to 15 years with acute fractures in the ED setting [1,[6][7][8]. INF has been shown to be equivalent or superior to morphine that is administered orally, intravenously, and intramuscularly and equivalent to intravenously administered fentanyl in providing pain control in children for many painful procedures [9].We found the same results in our study. INF has a strong safety profile, it is easily available in the hospital setting, and does not require additional pharmacy compounding in its commercially available form. This strong evidence, in addition to the significant ease of administration and no requirement for intravenous line placement, make it a potentially superior option and/or adjunct treatment for acute and procedural pain control in children. We started using it within the framework of ongoing study in the patient's triage. When compared with current practices, it has the potential to improve patient and family satisfaction and could have further implications related to improved cost-effectiveness and quality of care [10]. The IN route offers more flexibility to the nursing staff; they can administer repeated doses to titrate against pain. In addition, it has the potential to be used in a patient controlled self-administered manner [5].

Conclusion
The intranasal fentanyl can be a good option for analgesia in case of renal colic because it provides a quick pain relief and its use is safe.
Confirmation of its benefits requires studies on larger cohorts.