Peripheral Nerve Block Anaesthesia for Ankle Fracture Surgery - an Exploratory Study: Is Rebound Pain a Problem?

The purpose of this exploratory study is to characterize the postoperative pain profile of patients undergoing operation with internal fixation of an ankle fracture under nerve block anaesthesia. Special attention is payed towards the possible existence and clinical relevance of a rebound pain phenomenon upon cessation of the nerve block.

Results are used to guide the set up of a randomized controlled trial on the subject.

Study Overview

• Status: Completed
• Conditions: Postoperative Pain

Detailed Description

Peripheral nerve blocks (PNB) are widely used as anaesthesia and postoperative pain control for surgery. Several studies have suggested multiple benefits of PNB's but primarily shown in elective surgery. Acute conditions like ankle fractures have a different pain profile and risks and benefits of PNB's have not been sufficiently researched in these cases.

A recent study (Goldstein et al. 2012) suggested that a rebound pain effect occur upon cessation of PNB effect defined as a pain increase to a significantly higher level than observed in patients with no PNB at the same point after surgery.

With this prospective, exploratory study we aim to examine the postoperative pain profile after PNB anaesthesia for ankle fracture surgery with focus on plausibility of a rebound pain effect (as defined above) upon PNB cessation.

Secondarily to explore a variety of factors related to postoperative pain profile and feasibility of PNB anaesthesia for ankle surgery including efficacy, risk factors, time factors as well as postoperative recovery and overall patient satisfaction. Results will provide focus for a following randomized controlled trial.

• Study Type: Observational
• Enrollment (Actual): 21

Contacts and Locations

Study Locations

• Denmark
  • Herlev, Denmark, DK-2730
    • Herlev Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Patients scheduled for internal fixation of an ankle fracture under PNB-anaesthesia at Herlev Hospital identified from the operation booking system via consecutive screening.

Eligible ankle fractures will be those of anatomically uni-, bi- or trimalleolar composition including syndesmotic injury with distal but not proximal fibular fracture. The "third malleolus" is the distal posterior edge of the tibia. Fractures needing external fixation or causing ankle dislocation in need of imminent surgery is not eligible.

Description

Inclusion Criteria:

• Patients >= 18 years old scheduled for internal fixation of an ankle fracture as defined above.
• Ability to read and understand Danish and give informed oral and written consent

Exclusion Criteria:

• Multitrauma patients / other simultaneous fractures
• Cognitive or psychiatric dysfunction causing expected inability to comply with study protocol
• "CAVE" nonsteroidal antiinflammatory drugs (NSAID) or Morphine or Local Anaesthetics as evaluated by anesthesiologist for any reason
• Primary investigator unavailable for PNB administration at scheduled time of operation
• Infection at PNB injection site
• Time from fracture to operation > 5 days
• Existing neuropathy with functional impairment of the fractured extremity
• Bodyweight < 50 kg
• Daily use of opioids > 2 weeks preoperatively
• Pregnancy
• Nephropathy requiring dialysis

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Clinically relevant pain increase based on analysis of Numeric Rating Scale pain score (NRS) area under the curve (AUC) for the time period 12-24 hours compared to 0-12 hours postoperatively.	Pain scores are assessed and marked by the patient on a 0-10 numeric rating pain scale (NRS).	0, 2, 4, 6, 9, 12, 15, 18, 21 and 24 hours postoperatively

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Opioid use 12-24 hours compared to 0-12 hours postoperatively	Rescue morphine doses are administered intravenously via a patient controlled analgesia (PCA) pump when needed. Times of use are electronically registered.	0-24 hours continuous measurement
Calculated Composite Score for the time intervals 0-24h, 0-12h and 12-24h postoperatively	We will calculate the "Silverman" composite score of opioid use and pain score combined. This in order to illustrate any increase in pain and to use for sample size calculations for a future randomised study on the subject.	0-24 hours postoperatively
Time to first opioid dose postoperatively		0-24 hours postoperatively
Time to patient estimated cessation of block effect		0-24 hours postoperatively
NRS day 1-7 as both "average" and "worst" of the day	NRS are filled out by the patient in a diary.	Days 1-7 postoperatively
Daily opioid consumption day 1-7	Registered in a diary.	Days 1-7 postoperatively

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Clinically relevant pain increase based on analysis of Numeric Rating Scale pain score (NRS) area under the curve (AUC) after cessation of nerve block compared to before cessation of nerve block.	The average postoperative time to cessation of nerve block defining the time periods for this comparison will be defined after visual evaluation of the given pain profiles.	0, 2, 4, 6, 9, 12, 15, 18, 21 and 24 hours postoperatively
Score of the Quality of Recovery-15 (QoR-15) questionnaire preoperatively and on postoperative day 1.	Validation of the Danish translation of QoR-15 in this population of patients undergoing acute orthopaedic surgery under PNB-anaesthesia. A Danish version of the QoR-15 questionnaire is currently being validated in a mixed surgical patient population receiving surgery under general anaesthesia. We will attempt to validate the questionnaire on patients receiving nerve block (PNB) anaesthesia.	Preoperatively and postoperative day 1
QoR-15 questionnaire score on day 1, 2 and 7 postoperatively		Postoperative day 1, 2 and 7.
Length of postoperative stay in hospital		Up to 3 weeks
Time to first meal/appetite postoperatively		0-24 hours postoperatively
Incidence of postoperative nerve symptoms (PONS) on day 7	Telephone interview	Postoperative day 7
Postoperative nausea and vomiting (PONV) 24 hours postoperatively		0-24 hours postoperatively
Antiemetic medication 24h postoperatively		0-24 hours postoperatively
Time used for PNB administration		Preoperatively
Time to PNB effect on sensory and motor function		Preoperatively
Length of stay in the Operation Room (OR) - total and pre- and post-operatively		Operation day
Duration of surgery		Operation day
Partial block rate and Failed block rate	Partial = need for supplemental block preoperatively (if PNB seems insufficient after 30 min). Failed = need for General Anaesthesia.	Operation day
Need for PACU admission postoperatively	Most patients are expected to be send directly to the Orthopaedic ward following surgery. If not, the reason is noted.	Operation day

Collaborators and Investigators

• Sponsor: Herlev Hospital
• Investigators: Principal Investigator: Rune Sort, MD, Department of Anaesthesiology, Herlev Hospital; Study Director: Ann M Møller, Prof., DMSc, Department of Anaesthesiology, Herlev Hospital

Publications and helpful links

General Publications

• Sort R, Brorson S, Gogenur I, Nielsen JK, Moller AM. Rebound pain following peripheral nerve block anaesthesia in acute ankle fracture surgery: An exploratory pilot study. Acta Anaesthesiol Scand. 2019 Mar;63(3):396-402. doi: 10.1111/aas.13290. Epub 2018 Nov 8.

Study record dates

Study Major Dates

• Study Start: March 1, 2014
• Primary Completion (Actual): December 1, 2014
• Study Completion (Actual): March 1, 2015

Study Registration Dates

• First Submitted: March 24, 2014
• First Submitted That Met QC Criteria: March 27, 2014
• First Posted (Estimate): March 31, 2014

Study Record Updates

• Last Update Posted (Estimate): April 20, 2015
• Last Update Submitted That Met QC Criteria: April 17, 2015
• Last Verified: April 1, 2015

More Information

Terms related to this study

• Keywords: Postoperative pain; Ankle fracture; Nerve block; Rebound pain; Pain profile
• Additional Relevant MeSH Terms: Pathologic Processes; Postoperative Complications; Pain; Neurologic Manifestations; Fractures, Bone; Wounds and Injuries; Pain, Postoperative; Ankle Fractures
• Other Study ID Numbers: PAnFractRebound-01