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Background  Rib fractures are the most common thoracic injury  Rib fractures are associated with an increase in hospital morbidity and mortality  Pulmonary function can be compromised  Pain control is critical in decreasing the pulmonary complications

Lidocaine 5% patch Mechanism  Penetrates the skin  Binds sodium channels  Block influx sodium  Reduce abnormal ectopic discharges produced by damaged nerves

Lidocaine Patch Use  FDA Approval:  Post herpetic neuralgia  Other Studies:  Back pain  Headache  Postoperative pain after lap ventral hernia repair  Trauma patients with rib fractures

Hypothesis  The lidocaine patch would reduce the amount of narcotic pain medication used by hospitalized traumatically injured patients with rib fractures.

Study Design  Randomized, double blinded placebo controlled  Level I evidence  Setting  Spectrum Health – Butterworth Hospital  Jan 2007 – Aug 2008

Intervention  Randomized trauma patients with rib fractures to receive either Lidocaine or placebo patch  Data collected for 72 hours Age Sex Injury Severity Score History of asthma/COPD Mechanism of injury Number of rib fractures Chest tube placement History of tobacco use and current use

Patch Specifics  10 x 14 cm  5% lidocaine applied to non-woven polyester felt backing  700 mg lidocaine, 3 + 2% absorbed  Mean blood concentration 0.13 µg/mL (1/10 of the therapeutic concentration for arrhythmias)

Outcome Variable Assessment  10 point pain scale administered by nursing  Pain assessments were conducted per hospital protocol (each shift and prior to administering pain medication)  IV and PO narcotic pain medications were analyzed independently  Incidence of pulmonary complications  Length of stay

Patients  Inclusion Criteria  Trauma patients with rib fracture on CT/Xray  Age > 18 years of age  Exclusion Criteria  Inability to communicate a pain score  Inability to use an incentive spirometer  History lidocaine allergy  Open wounds at the site of patch application

Primary Outcome  Decrease narcotic use when use lidocaine patch after trauma injury with rib fracture

1278 Trauma admissions 495 Rib Fractures 58 Enrolled 33 Lidocaine25 Placebo

p = 0.88 Pain Assessment and Narcotic Utilization

Outcome comparison of Lidocaine and Placebo groups Lidocaine groupPlacebo group Total IV narcotics used (in mg morphine)* 23 (7, 102)26 (8, 59)P = 0.88 Total po narcotics used (in tabs Vicodin)* 4 (2, 10)7 (2.5, 14)P = 0.22 Pain score # P = 0.39 * Median (interquartile range) # Mean + SEM

Outcome comparison of Lidocaine and Placebo groups Lidocaine groupPlacebo group Pulmonary complications # 72.7% (24/33)72% (18/25)P = 0.95 Length of Stay # P = 0.28 # Mean + SEM* Median (interquartile range)

Pre-Injury Characteristics of Lidocaine and Placebo groups CharacteristicLidocaine group n = 33 Placebo group n = 25 Age* P = 0.31 Gender (% male)72.7% (24/33)76% (19/25)P = 0.78 History lung disease9.1% (3/33)20% (5/25)P = 0.27 History of smoking39.4% (13/33)24% (6/25)P = 0.22 Current smoker24.2% (8/33)20% (5/25)P = 0.70 * Mean + SEM

Mechanism of Injury

Injury Characteristics CharacteristicLidocaine group n = 33 Placebo group n = 25 Injury Severity Score* P = 0.74 AIS (chest) # 3 (3-4) P = 0.17 Number of ribs fractured* P = 0.50 Chest tube placed36.4% (12/33)24% (6/25)P = 0.31 * Mean + SEM # Median (interquartile range)

Lidocaine Patch in Trauma Patients  Zink et al. Oregon Health & Science University. Presented at EAST. January 2009  Retrospective  29 patients each group  Lidocaine 5% patch patients had decreased pain scores, but no difference in narcotic use  Conclusion: Further prospective studies needed

Conclusions  Lidocaine patches do not decrease narcotic pain medication use in hospitalized trauma patients with rib fractures  No difference in  pain scores  pulmonary complications  length of stay  Should not be routinely used in multi-system trauma patients with rib fractures