Relief Efficacy of Lidocaine Versus Morphine for Acute Renal Colic in the Emergency Department

Purpose

● To determine whether IV lidocaine is more efficacious than IV morphine in decreasing or resolving acute renal colic pain refractory to initial treatment with parenteral ketorolac

Primary Objective ● To compare the efficacy of IV lidocaine versus IV morphine in achieving at least 50% reduction of pain score at 30 minutes for renal colic requiring rescue medication after initial treatment with parenteral ketorolac

Secondary Objectives

• To compare reduction in pain scores at 15, 60, and 90 minutes between the two intervention groups;
• To determine if there is a statistically significant difference in emergency department length of stay (ED LOS) between the two intervention groups
• To determine if there is a statistically significant difference in need for further rescue medications between the two intervention groups
• To determine the incidence of adverse effects between the two intervention groups
• To evaluate whether there is a correlation between age and efficacy of treatment between the two intervention groups

Study Design This study is a prospective randomized controlled trial. Study participants will be randomized to receive either IV lidocaine or IV morphine if they fail initial standard treatment with parenteral ketorolac for suspected acute renal colic.

Study Date Range and Duration The estimated study period will be from 1/1/2026 to 12/31/2027.

The study will be carried out for two calendar years, and may be halted early when sufficient participant enrollment has occurred.

Number of Study Sites

• Loma Linda University Medical Center - Adult Emergency Department (Adult ED)
• Loma Linda University Medical Center - East Campus Advanced Urgent Care (AUC)

Primary Outcome Variables

● Response to treatment: pain assessment using a numeric rating scale (0 to 10) at 30 minutes

Secondary and Exploratory Outcome Variables

• Response to treatment: pain assessment using a numeric rating scale (0 to 10) at 15, 60, and 90 minutes
• Adverse events attributed to IV lidocaine or IV morphine
• ED LOS
• Need for additional rescue medications after either IV lidocaine or IV morphine

Study Population Study participants will be enrolled from patients who have suspected renal colic as determined by the treating clinician at the Loma Linda Adult ED or AUC.

Number of Participants This study seeks to enroll at least 248 patients over the study period, with at least 190 patients required to achieve a standard statistical power of 80%. Patients will be randomized into two groups - 124 patients per group.

Study Schedule All data and information, including consent and screening, will be gathered during the course of a patient's single visit at the Loma Linda Adult ED or AUC.

Inclusion criteria

In order to be eligible for inclusion in the study, an individual must meet all of the following criteria:

• Age ≥ 18 years at time of visit
• Able and willing to consent for participation in study
• Documentation of suspected renal colic as primary complaint as evidenced by reported flank pain, back pain, abdominal pain, or groin pain, or as determined by the treating clinician
• Requires additional treatment due to inadequate analgesia or clinical suspicion of unsafe discharge secondary to pain after initial treatment with parenteral ketorolac

Exclusion criteria

Any individual who meets any of the following criteria will be excluded from participation in this study:

• Age < 18 years
• Use of analgesia for renal colic within 6 hours prior to clinician evaluation
• Inability or unwillingness to consent for participation in study
• Experienced a severe adverse event that required clinician intervention after initial treatment with parenteral ketorolac
• Documented history of allergic or anaphylactic reaction to NSAIDs, lidocaine, or morphine
• Documented history of cardiac arrhythmias
• Documented history of chronic use of opioid medications for unrelated diagnoses
• Currently pregnant
• Documented history of end-stage renal or hepatic dysfunction
• Clinical contraindications to NSAIDs, lidocaine, or morphine per clinician discretion