Effects of ketorolac versus bupivacaine coadministration during patient-controlled hydromorphone epidural analgesia after thoracotomy procedures

We studied the comparative effects of ketorolac versus bupivacaine supplementation of hydromorphone (HM) patient-controlled epidural analgesia (PCEA) on the HM requirement, postoperative pain, and pulmonary function in 62 consenting patients after thoracotomy procedures. Patients were randomly assigned to receive one of three different combinations of analgesic medications after the operation according to a double-blind, placebo-controlled study. The treatment groups consisted of: Group 1 (n = 23): PCEA HM 3-mL (0.15 mg) bolus doses + saline 1 mL intravenously (IV) q6h, Group 2 (n = 20): PCEA HM (0.15 mg) in 0.125% bupivacaine 3-mL bolus doses + saline 1 mL IV q6h, and Group 3 (n = 19): PCEA HM 3-mL (0.15 mg) bolus doses + ketorolac 1 mL (30 mg) IV q6h. Epidural HM and supplemental analgesic requirements, pain visual analog scale (VAS) scores, the incidence of nonincisional pain, and side effects were recorded at 24 and 48 h after surgery. Bedside pulmonary function tests were performed using a Puritan Bennett 100TM (Puritan-Bennett Corp., Wilmington, MA) spirometer before and 24 and 48 h after surgery. IV ketorolac supplementation of HM PCEA significantly reduced the incidence of nonincisional pain and the HM requirement over 48 h compared with the HM PCEA alone group (7% vs 26%; 3 +/- 1.6 mg vs 5.3 +/- 2.8 mg). Both ketorolac and bupivacaine supplementation of HM PCEA reduced the severity of pain on coughing and on movement compared with HM PCEA alone on postoperative day (POD) 1. Significant reductions in forced vital capacity, forced expiratory volume in 1 s, forced expiratory flow 25%-75% of the vital capacity, and peak expiratory flow rate (PEFR) were noted on PODs 1 and 2 in all three treatment groups. The decrease in PEFR on PODs 1 and 2 was significantly less with ketorolac compared with bupivacaine supplementation. We conclude that ketorolac supplementation of HM PCEA reduces the incidence of nonincisional pain and HM requirement compared with HM PCEA alone and may have a beneficial effect on pulmonary function compared with bupivacaine supplementation of HM PCEA in postthoracotomy patients.

Parenteral ketorolac: the risk for acute renal failure

BACKGROUND

Acute renal failure has been associated with parenteral ketorolac tromethamine, but the risk that is associated with this therapy has not been quantified.

OBJECTIVE

To compare the risk for acute renal failure associated with ketorolac with that associated with opioids.

DESIGN

Retrospective cohort study.

SETTING

35 hospitals in or near Philadelphia.

PATIENTS

Patients receiving 10,219 courses of parenteral ketorolac and patients receiving 10,145 courses of parenteral opioids.

MEASUREMENTS

Acute renal failure was defined by 1) an increase in the serum creatinine concentration of 50% or more and 2) either an absolute increase of 44.2 mumol/L or more for concentrations that were less than 132.6 mumol/L at baseline or an absolute increase of 88.4 mumol/L or more for concentrations that were 132.6 mumol/L or more at baseline. In addition, a secondary definition required a diagnosis by a physician.

RESULTS

The overall incidence of acute renal failure was 1.1% after therapy with either ketorolac or opioids. Multivariate-adjusted rate ratios comparing ketorolac with opioids for acute renal failure were 1.09 (95% CI, 0.83 to 1.42) overall, 1.00 (CI, 0.76 to 1.33) for less than 5 days of therapy, and 2.08 (CI, 1.08 to 4.00; P = 0.03) for more than 5 days of therapy. Similar results were obtained when the secondary definition of acute renal failure was used.

CONCLUSIONS

Overall, acute renal failure was uncommon in this hospitalized population. Compared with opioids, ketorolac administered for 5 days or less did not increase the rate of renal failure. However, among patients who were treated with analgesics for more than 5 days, ketorolac may be associated with an elevated rate of acute renal failure.

[Postoperative pain control]

Pain was and in part still is a constant feature of surgical practice: before, during and after surgery. To start with painful symptoms represent a fundamental diagnostic element, given that in over 60% of cases pain is the primary indication for surgery. During the operation, pain used to constitute the main impediment to the surgeon's activities, until the introduction of ether and the birth of modern anesthesia. Lastly, the postoperative period is also painful so much so that whereas until fifty years ago patients were above all afraid of the operation, patients nowadays are concerned about the pain during the days after the operation. Moreover, over 50% of patients undergoing surgery are unsatisfied with the treatment of postoperative pain, in spite of the fact that drugs are available which enable us to control it. The authors studied the quality of postoperative analgesia in 357 patients, who received treatment with ketorolac tromethamine 30 mg i.v. on leaving the operating theatre, and subsequently i.m. every 8 hours starting from 3 hours after surgery. The use of ketorolac tromethanine demonstrated effective analgesia and was well accepted by patients, without revealing any particular collateral effects.

Acetaminophen or ketorolac for post myringotomy pain in children? A prospective, double-blinded comparison

Myringotomy with tube placement (BMT) is the most frequent surgical procedure performed in children. The purpose of this prospective, double-blinded study was to determine if 15 mg.kg-1 of acetaminophen (paracetamol) provides analgesia similar to that provided by ketorolac, 1 mg.kg-1, at a lower cost. One-hundred-and-thirty-two children, ages six months to nine years, scheduled for elective BMT were randomized to receive oral acetaminophen or ketorolac 30 min preoperatively. An Objective Pain Scale score was assessed upon arrival to the PACU and at five, ten and 20 min. Time of awakening, time of PACU and day surgery discharge and incidence of vomiting were recorded. Groups were comparable in demographics, side effects and time to discharge. Median pain scores were lower in the ketorolac group at five and ten min but no differences were seen at discharge nor in postdischarge analgesic requirements. Is ten min of better analgesia worth the cost of ketorolac? We conclude that the slight analgesic benefit from ketorolac does not justify its cost in this setting.

Colonoscopy by a family physician: a 9-year experience of 1048 procedures

BACKGROUND

In the last 15 years, family physicians and general internists have adopted flexible fiberoptic endoscopy as a procedure to screen patients at risk of premature death from colorectal cancer. There has been controversy regarding the ability of non-fellowship-trained primary care physicians to extend this experience to full colonoscopy.

METHODS

The results of 1048 consecutive colonoscopy examinations performed by a family physician over a 9-year period were tabulated. Outcomes measured included the reach-the-cecum rate (RCR), use of medication, complication rate, and diagnostic yield. In a convenience sample of 110 cases, the effectiveness of the non-narcotic analgesic ketorolac was assessed by the RCR. Outcomes of cases in which ketorolac was used were compared with cases in which traditional sedation and analgesia were used.

RESULT

A high diagnostic yield without significant complications was noted. The RCR for nonmedicated patients was 36%. Among all medicated cases, the RCR was 93%. In patients who were given the non-narcotic analgesic ketorolac, the RCR was 96%, compared with 95% in patients not given ketorolac.

CONCLUSIONS

A family physician in rural practice was able to attain and sustain a state-of-the-art, reach-the-cecum rate over a 9-year period. This service resulted in a high diagnostic yield, high degree of safety, and satisfactory results for the community. Ketorolac is an effective alternative for patients who may be hypersensitive to narcotic analgesia/sedation.

Effect of diclofenac, ketorolac, and fluorometholone on arachidonic acid metabolites following excimer laser corneal surgery

OBJECTIVE

To compare the ability of several topical anti-inflammatory agents to modulate the production of prostaglandin E2 after excimer laser ablation in rabbit cornea.

METHODS

Adult New Zealand white rabbits were subjected to phototherapeutic keratectomy with a commercially available excimer laser. Prostaglandin E2 and leukotriene B4 were detected by enzyme-linked immunoassay, and leukocyte infiltration was determined histologically.

RESULTS

Prostaglandin E2 and leukocyte infiltration increased in the cornea after excimer ablation. Treatment with topical fluorometholone and diclofenac sodium significantly reduced prostaglandin E2 levels. Corneas treated with diclofenac had significantly higher levels of leukocyte infiltration than those treated with ketorolac tromethamine. No changes in leukotriene B4 levels were detected in this model.

CONCLUSIONS

As a group, topical anti-inflammatory medications tend to lower prostaglandin E2 levels in rabbit corneas subjected to excimer ablation, but differ in their ability to reduce polymorphonuclear leukocyte infiltration. Further work is needed in this model to understand how these drugs alter leukocyte infiltration of the remaining stromal bed.

A comparison of intramuscular ketorolac with indomethacin suppositories in the treatment of pain after oral surgery

The analgesic effects of 30 mg intramuscular ketorolac were compared with those of rectal indomethacin in 100 mg and 200 mg doses in 66 patients in a single-blinded trial. Pain scores and the incidence of nausea and vomiting were assessed at 30, 60 and 120 minutes postoperatively, at discharge (4 hours) and on the evening of surgery. Area under the curve of pain scores versus time for pain at 30, 60 and 120 minutes postoperatively was significantly lower in the ketorolac group compared to indomethacin 100 mg and 200 mg groups. There were no significant differences in the pain scores at discharge or at home on the evening of surgery. At 60 minutes postoperatively there was significantly more nausea and vomiting in the indomethacin 200 mg group; at all other time-points there was no significant difference between the groups with regard to nausea and vomiting. The power of the study to determine the significance of side-effects between the groups was low.

Diclofenac and Ketorolac in the Treatment of Pain after Photorefractive Keratectomy

BACKGROUND

Photorefractive keratectomy (PRK) can produce significant ocular pain. Topical diclofenac, a non-steroidal anti-inflammatory drug (NSAID), is effective in the reduction of this pain. This study compares a second NSAID, ketorolac, to diclofenac.

METHODS

This prospective matched-control study involved 102 eyes of 102 patients. Prior to PRK, patients were randomly assigned to receive ketorolac or diclofenac drops. At the first postoperative visit, a standardized questionnaire was used to assess the patient's average and peak levels of discomfort. In addition, the quantities of acetaminophen and codeine consumed were recorded.

RESULTS

The overall level of discomfort was 1.53 +/- 0.64 for diclofenac and 1.88 +/- 0.55 for ketorolac (scale: 0 to 4) (P = 0.004). The diclofenac group reported a peak discomfort level of 2.0 +/- 0.75 and the ketorolac group reported 2.3 +/- 0.62 (P > 0.05). The diclofenac group consumed 2000 +/- 1150 mg of acetaminophen and 92 +/- 54 mg of codeine whereas the ketorolac group consumed 2150 +/- 940 of acetaminophen and 98 +/- 50 mg of codeine (P > 0.05).

CONCLUSIONS

The differences in levels of peak discomfort, acetaminophen ingestion, and codeine ingestion, were not statistically significant. As compared to ketorolac, diclofenac resulted in a statistically significant lower mean overall discomfort.

Recovery after propofol with and without intraoperative fentanyl in patients undergoing ambulatory gynecologic laparoscopy

This prospective, randomized double-blind study was conducted to examine the effect of intraoperative opioid (fentanyl) supplementation on postoperative analgesia, emesis, and recovery in ambulatory patients receiving propofol-nitrous oxide anesthesia. Eighty patients undergoing ambulatory gynecologic laparoscopy participated. Confounding variables that could influence the incidence of postoperative emesis were controlled. Patients received either fentanyl 100 micrograms (Group I) or ketorolac 60 mg (Group II) intravenously (IV) at the time of anesthetic induction. No further analgesic supplements were given intraoperatively. Anesthesia was induced with propofol and maintained with propofol-nitrous oxide. Atracurium was used for muscle relaxation and reversed with neostigmine and glycopyrrolate. Postoperative pain during early recovery was treated with IV fentanyl 25-50 micrograms (Group I) or IV ketorolac 15-30 mg (Group II). Subsequent breakthrough pain in both groups was treated with IV fentanyl 25 micrograms increments as needed (rescue analgesia). Eighty-four percent of patients in Group I required analgesics during early recovery versus 56% of patients in Group II (P < 0.05). Maintenance dose of propofol was significantly lower in Group I (129 +/- 35 micrograms.kg-1.min-1 than in Group II (170 +/- 63 micrograms.kg-1.min-1. Immediate recovery (emergence) in the two groups was comparable, despite different propofol requirements. Although the incidence of emetic sequelae in the postanesthesia care unit was not significantly different between the two treatment groups, a significantly larger number of patients in Group I (fentanyl group) had emetic sequelae that required therapeutic intervention (Group I 29% versus Group II 10%). Patients in Group I also took a significantly longer time to ambulate and meet criteria for home discharge. These results indicate that, in patients undergoing ambulatory gynecologic laparoscopy, the practice of administering a small dose of fentanyl at the time of anesthetic induction reduces maintenance propofol requirement, but fails to provide effective postoperative analgesia. Fentanyl administration at anesthetic induction increased the need for rescue antiemetics. The relative severity of emetic sequelae could have contributed to delay in ambulation and discharge.

Comparison of electromotive drug administration with ketorolac or with placebo in patients with pain from rheumatic disease: a double-masked study

This study was undertaken to assess the efficacy of ketorolac compared with placebo when delivered by electromotive drug administration (EMDA) in patients with pain from rheumatic disease. In EMDA, or iontophoresis, a low-intensity electric current is applied over the skin to deliver medication into body tissues. Although EMDA has been used to treat patients with various diseases, controlled studies are lacking in patients with rheumatic disease. This double-masked study included 60 patients (43 women and 17 men) aged 31 to 80 years with the following conditions: 12, epicondylitis; 30, scapulohumeral periarthritis; 10, gonalgia; and 8, metatarsalgia. They were divided randomly by a physician into 2 groups of 30 patients each for 5 sessions of active treatment (30 mg of ketorolac) or placebo (5 mL of normal saline). Treatment took place every other day for 20 minutes. Immediately before and after the five treatment sessions and 7 days after treatment ended, both patient and physician measured the degree of pain using a categoric scale (no pain, slight pain, intermediate pain, strong pain, and very strong pain) and evaluated pain intensity using the Scott and Huskisson Visual Analogue Scale (VAS). Seven days after treatment ended, both physician and patient judged the result of treatment using a second categoric scale (no improvement or intermediate, good, or very good result). Both ketorolac and placebo provided immediate, significant pain relief when delivered by EMDA, but only those patients receiving ketorolac experienced a further reduction in pain 7 days after treatment; those receiving placebo experienced a slight increase in pain. VAS values differed significantly between the two groups. Poor results (no improvement) were significantly higher in the placebo-treated group, while good results were significantly higher in the ketorolac-treated group. No patient reported any adverse effects during treatment. This study demonstrates that ketorolac relieves pain when delivered by EMDA and offers longer-lasting pain relief than does placebo.

Effect of intramuscular intraoperative pain medication on narcotic usage after laparoscopic cholecystectomy

The purpose of this randomized, double-blind, clinical trial was to determine whether intraoperative, intramuscular (IM) injections of meperidine or ketorolac would improve postoperative pain relief in patients undergoing elective laparoscopic cholecystectomy. A total of 125 patients were entered into five study groups: 1) (N = 23) control placebo; 2) (N = 31) meperidine 100 mg IM intraoperative preprocedure; 3) (N = 20) meperidine 100 mg IM intraoperative postprocedure; 4) (N = 25) ketorolac tromethamine 60 mg IM intraoperative preprocedure; 5) (N = 26) ketorolac tromethamine 60 mg IM postprocedure. All groups were analyzed by comparing the amount of pain medication received in the recovery room, the time until first oral pain medication was requested, the overall amount of pain medication used in the first 24 hours, the percent requiring IM medication, and the pain score ratings from each group. There was decreased pain medication usage in the recovery room in all groups compared to control (P < 0.05). Group 4 had a longer painfree interval than meperidine groups or control. Both Groups 4 and 5 had decreased postoperative narcotic usage. Finally, the analogue pain scores showed that both ketorolac groups had significantly less postoperative pain compared to control, whereas the meperidine groups showed no improvement in postoperative pain relief. Intraoperative ketorolac given preprocedure or postprocedure significantly improved postoperative pain management and facilitated the transition to oral pain medication.

Comparison of wound infiltration with ketorolac versus intravenous regional anesthesia with ketorolac for postoperative analgesia following ambulatory hand surgery

BACKGROUND AND OBJECTIVES

The purpose of this study was to assess the analgesic effectiveness of ketorolac administered with lidocaine via intravenous regional asesthesia (IVRA) or via wound infiltration following ambulatory hand surgery.

METHODS

The patient population in this double-blind study consisted of 60 patients scheduled for elective ambulatory hand surgery, who were divided into three groups of 20 each. All patients received IVRA with 40 mL 0.5% lidocaine and 5 mL 1% lidocaine infiltrated into the surgical site. Group 1, the control group, received no additional medications; group 2 had 60 mg ketorolac added to the lidocaine used for IVRA; and group 3 had 60 mg ketorolac added to the lidocaine used for wound infiltration. Postoperative pain was assessed by a 10-cm visual analog scale. VAS) 1 hour and 2 hours after tourniquet deflation. In the postanesthesia care unit analgesia was provided with fentanyl until the VAS score reached 3 or lower. Patients were instructed to take one Tylenol No. 3 (acetaminophen with codeine) tablet every 4 hours as needed at home. They were contacted the next day, and the time to first additional narcotics and the total number of tablets taken were recoded.

RESULTS

No differences in demographic variables or in operative, tourniquet, or discharge times were noted among the groups. The VAS scores were significantly lower in the two groups who received ketorolac than in the control group (P < .05); the mean time from tourniquet release to first medication was 109 +/- 73 minutes for group 1, 467 +/- 431 for group 2, and 393 +/- 312 for group 3 (P < .05); and the number of tablets taken was 4.1 +/- 1.3 for group 1, 1.8 +/- 1.2 for group 2, and 2.0 +/- 1.3 for group 3 (P < .05).

CONCLUSION

Ketorolac provides similar postoperative analgesia after ambulatory hand surgery when administered with lidocaine either by IVRA or by wound infiltration.

Cyclic vomiting: association with multiple homeostatic abnormalities and response to ketorolac

Cyclic vomiting is a rare syndrome that over the years has variously been ascribed to psychogenic causes, sensory seizures, abdominal migraine, and more recently, to mechanical or electrical disturbances in gastric physiology. We describe the case of a 65-year-old white diabetic female with a 10-yr history of recurrent episodes of nausea and vomiting, occurring every 10-12 days and lasting approximately 1-3 days at a time. These episodes were accompanied by edema, mild temperature elevations, and remarkable elevations in blood pressure. In between these episodes, the patient remained asymptomatic. Initial screening tests were also negative except for moderate gastroparesis. However, antral motility was found to be normal, as was an electrogastrogram. Detailed neurological and psychiatric evaluations were negative. Trials of erythromycin, metoclopramide, naloxone, ondansetron, and amitryptiline were unsuccessful. Serial endocrinological testing revealed that an episode of vomiting was always preceded by an abnormal elevation in at least one of the following: serum adrenocorticotropic hormone, serum cortisol, or urinary cortisol. In the midst of an episode, all three values were exceedingly high (e.g., > 10-fold increases in 24-hr urinary cortisol levels). Fluctuations of a milder degree, though still abnormally high, were also noted in between cycles at times when the patient was completely asymptomatic. High-dose dexamethasone suppressed these hormonal surges completely but not the clinical symptoms, which continued undisturbed. The patient was finally given a trial of intramuscular ketorolac during one of her episodes, which produced prompt and sustained relief. During the next few weeks, she was given this drug each time her symptoms commenced, and each time it appeared that her cycle had been aborted. She has since been able to terminate her episodes promptly and completely by self-administration of ketorolac. We speculate that her syndrome is caused by a poorly characterized disorder of endogenous prostaglandin release, resulting not only in derangements in the hypothalamic pituitary system but also in nausea and vomiting.

On the protection by ketorolac of reperfusion-induced heart damage

This study shows that the nonsteroidal antiinflammatory drug, ketorolac, protects against myocardial damage induced by reperfusion. This effect was analyzed after 5 min of coronary occlusion in rat hearts. The results indicate that ketorolac, at a dose of 1 mg/kg, effectively protects the heart against reperfusion arrhythmias. Furthermore, it protects from the release of lactate dehydrogenase and creatine kinase to the plasma. We propose that the protective effect of the drug might be due to its chelating action on calcium ions, thus preventing the overload of such cation in myocardial cells.

Preoperative ketorolac administration has no preemptive analgesic effect for minor orthopaedic surgery

The utility of preoperative ketorolac administration to reduce the intensity and duration of postoperative pain was compared with placebo in a randomized double-blind design of 60 ASA 1-2 patients scheduled for minor orthopaedic surgery. No opioids nor local anaesthetic blocks were used during surgery. The patients received either 30 mg ketorolac IV before surgery followed by a placebo injection after surgery or the reverse. Postoperative pain intensity was assessed repeatedly for 6 h using a visual analogue scale. No differences in pain intensity were observed between the two groups except for the initial 15-min postoperative assessments in the ketorolac group. The time to first rescue morphine administration and the total morphine consumption during the 6-h observation period were similar. It is concluded that the preoperative administration of ketorolac did not provide a significant preemptive analgesic benefit with regard to postoperative pain relief and opioid dose-sparing effect.

Ketorolac continuous infusion: a case report and review of the literature

We report a case of intractable pain due to metastatic carcinoma that was effectively managed with a continuous intravenous (IV) infusion of ketorolac. Unlike previous reports of short-term continuous IV ketorolac for postoperative analgesia, this case is unique because of the etiology of the pain and the duration of treatment. The published literature on continuous administration of ketorolac by the intravenous, intramuscular, and subcutaneous routes is also reviewed.

Intraoperative ketorolac and posttonsillectomy bleeding

OBJECTIVE

To determine the occurrence of posttonsillectomy bleeding in patients who received intraoperative ketorolac tromethamine.

DESIGN

Retrospective analysis.

SETTING

Academic tertiary care center.

PATIENTS

Three hundred eleven patients who underwent tonsillectomy in an 18-month period.

MAIN OUTCOME MEASURE

Occurrence of bleeding complications in patients who received ketorolac during tonsillectomy.

RESULTS

Fifty-eight of 311 patients who underwent tonsillectomy received intraoperative ketorolac with an overall postoperative bleeding rate of 17%. This high rate of bleeding complications compares with 4.4% in the remaining 253 patients who received traditional opioid analgesics.

CONCLUSIONS

Until further controlled studies have been conducted, the use of ketorolac in patients undergoing tonsillectomy should be avoided because of the increased incidence of postoperative bleeding complications.

Ketorolac vs chlorpromazine in the treatment of acute migraine without aura. A prospective, randomized, double-blind trial

BACKGROUND

Many treatments for acute migraine exist. Chlorpromazine is effective but has serious side effects. Ketorolac has only rare side effects.

OBJECTIVE

To compare intramuscular ketorolac troinethamine with intravenous chlorpromazine hydrochloride in treating acute migraine.

METHODS

We performed a prospective, randomized, double-blind trial comparing the clinical effectiveness of 60 mg of intramuscular ketorolac tromethamine with 25 mg of intravenous chlorpromazine hydrochloride in patients with acute migraine headache seen in the emergency department. Pain intensity, quantitated using the Wong-Baker Faces Rating Scale, was measured every 30 minutes for 2 hours in the emergency department. Patients returned pain scores at 6, 12, 24, and 48 hours by mail.

RESULTS

Fifteen patients were entered into each treatment arm. No differences were seen between the mean pain scores or the mean change in pain scores. The ketorolac group mean (+/- SEM) pain score decreased from 4.07 +/- 0.18 to 0.73 +/- 0.3 in 2 hours. The chlorpromazine group pain score decreased from 4.47 +/- 0.17 to 0.87 +/- 0.4. Two of the 3 nonresponders responded to the alternate group's treatment. No side effects were seen.

CONCLUSIONS

Using 60 mg of intramuscular ketorolac tromethamine is as effective as 25 mg of intravenous chlorpromazine hydrochloride in the treatment of acute migraine headache. Patients who do not respond to one of these medications may respond to the other.

Ketorolac-induced acute renal failure in a previously healthy adolescent

Ketorolac has become an important component of analgesic regimens for children as well as adults because of its lack of adverse effects on respiratory, cardiovascular, and neurologic function. Although initially used parenterally in hospitalized patients, the development of an oral ketorolac dose form extended its use to the outpatient setting, where its potency has been considered an advantage over traditional therapies.1-3

Several cases of hyperkalemia and oliguric acute renal failure associated with ketorolac use have been reported in the medical literature.4-12 Elderly hospitalized patients receiving large doses of ketorolac intramuscularly (IM) after major surgery seem to be at greatest risk.

In vivo/in vitro correlations for four differently dissolving ketorolac tablets

This study assesses whether in vitro immediate release ketorolac tablet dissolution profiles (utilizing the recently proposed USP dissolution test for ketorolac tablets) can be correlated with in vivo plasma pharmacokinetic parameters. Four batches of ketorolac tablets were utilized: a ketorolac tablet batch that demonstrated a rapid dissolution rate during USP in vitro dissolution testing, two tablet batches that were manufactured such that they dissolved at moderate rates, and a tablet batch that was manufactured such that it dissolved at a distinctly slow rate. The single-dose mean pharmacokinetic characteristics and relative bioavailability of the four different 10 mg ketorolac tromethamine tablets were evaluated in 12 healthy volunteers in a randomized study of Latin square design. The amount dissolved of the various tablets at 10, 20, and 30 min was in the order of fast-dissolving tablets > medium-1-dissolving tablets = medium-2-dissolving tablets > slow-dissolving tablets. In general, the profiles of the average plasma concentrations for ketorolac were similar for the fast- and the two medium-dissolving tablet batches (even though a statistically significant difference was found between the tmax of the fast-dissolving tablet and one of the medium-dissolving tablet batches). The mean plasma concentrations for the slow-dissolving tablet, however, reached peak levels much later, with the peak also being significantly smaller. There were no statistically significant differences in the total AUC or in the mean plasma half-lives among the four formulations. Good correlations were obtained for mean tmax versus the percentage dissolved at 20, 30, and 45 min. Correlations were generally weaker for percentage dissolved versus Cmax or percentage bioavailability. This indicates that in vitro dissolution testing for immediate release ketorolac tablets can be a useful indicator of in vivo time to maximum plasma concentration when comparing similarly formulated tablets. Further, the proposed USP dissolution test and specification would have appropriately failed the slow-dissolving tablet batch, which demonstrated a significantly slower rate of absorption as per tmax and Cmax.

Comparison of intravenous ketorolac, meperidine, and both (balanced analgesia) for renal colic

STUDY OBJECTIVE

To compare the analgesic efficacy and safety of IV ketorolac, the only nonsteroidal antiinflammatory drug indicated for parenteral use in acute pain in the United States, with IV meperidine and with a combination of the two agents in renal colic.

METHODS

We carried out a double-blind, randomized, multicenter clinical trial in the emergency departments of four urban tertiary care teaching hospitals. Our study subjects were 154 patients with suspected renal colic. Each subject received an initial IV dose of ketorolac 60 mg, meperidine 50 mg, or both supplemented as needed beyond 30 minutes with additional doses of meperidine.

RESULTS

The main outcome measures were changes in pain-intensity and pain-relief scores, amount of supplemental meperidine required, end-of-study drug tolerability, and adverse events. Analyses of 106 subjects with confirmed renal colic indicated that ketorolac and the combination were significantly better than meperidine alone by all efficacy measures, including pain relief and time elapsed before the need for supplemental meperidine. By 30 minutes, 75% of the ketorolac group and 74% of the combination group had a 50% reduction in pain scores, compared with 23% of the meperidine group (P < .001). The ketorolac and combination groups did not differ significantly in any of the efficacy measures.

CONCLUSION

IV ketorolac, alone or in combination with meperidine, was superior to IV meperidine alone in moderate and severe renal colic. Because many subjects in all three treatment groups received supplemental meperidine and because response to ketorolac alone cannot be predicted, clinicians may choose to initiate treatment with a ketorolac-meperidine combination.