Analgesic effectiveness of ketorolac compared to meperidine in the rat formalin test

The rat formalin test is an analgesic behavioral observation assessment method that demonstrates two phases of nociceptive behavior. The test consists of injecting the right hind paw with a 5% formalin solution and then observing the animal for specific nociceptive behavior. The phases represent two different types of pain. Phase 1 is pain produced by direct nerve stimulation and phase 2 is an inflammation-induced pain. The nociceptive behavior measured in this experiment was licking and biting the injected paw. A comparison of nociceptive behavior was made when ketorolac and meperidine were injected (i.p.) 10 min prior to formalin injection. As expected, a biphasic pattern of licking and biting the injected paw ensued. It was found that ketorolac had no significant reduction in licking and biting, while meperidine dramatically reduced the nociceptive response in phase 1. In phase 2, both ketorolac and meperidine caused a reduction in licking and biting; however, meperidine reduced the nociceptive response to a greater extent. This experiment demonstrates that ketorolac, when compared to meperidine, is less effective in treating pain from inflammatory origin and is not effective in treating pain from direct nerve stimulation.

The effects on platelet aggregation and prostanoid biosynthesis of two parenteral analgesics: ketorolac tromethamine and dipyrone

The pharmacokinetics and effects on platelet function of dipyrone (1.0 g; 2.5 g; i.v.) and ketorolac tromethamine (30 mg; i.m.) were studied in a three-way crossover study in twelve healthy subjects. The biosynthesis of thromboxane A2 in clotting whole blood ex vivo as well as collagen-induced platelet aggregation were determined before and up to 48 h after administration. Both prostanoid biosynthesis and platelet aggregation were inhibited by ketorolac tromethamine for a significantly longer period of time than by both doses of dipyrone. The changes in platelet functions correlated well with the serum concentrations of ketorolac or 4-methylaminoantipyrine and 4-aminoantipyrine. Using the sigmoidal Emax model the mean serum concentration (SD) of ketorolac, 4-methylaminoantipyrine and 4-aminoantipyrine inhibiting platelet TXB2 generation by 50% (EC50) in vitro was found to be 0.088 +/- 0.031, 1.2 +/- 0.3 and 10.2 +/- 3.4 micrograms ml-1, respectively. In conclusion the recovery of platelet function after dipyrone administration is faster as compared to ketorolac tromethamine. This is in line with clinical observations and may be an advantage when these drugs are given as postoperative analgesics at the doses tested.

Nurse evaluation of a pain medication protocol in a selective postoperative population

Postoperative pain in 33 patients who underwent radical prostatectomy was managed by an intramuscular nonsteroidal antiinflammatory drug protocol rather than by administration of narcotics. Patients rated their perception of pain with a visual analog scale on the first postoperative day both before and after receiving ketorolac tromethamine. The medication was effective in relieving pain after this major operation. Costs were approximately one half that of the traditional narcotic protocol used before this study.

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.

The effects of chronic ketorolac tromethamine (toradol) on wound healing

Intramuscular ketorolac is a commonly used nonsteroidal anti-inflammatory (NSAI) agent for analgesia in surgical patients. Increasing numbers of surgical patients are chronically taking some form of an NSAI drug. We examined the effects of "chronic" intramuscular ketorolac on the healing of a closed linear surgical wound in the rat. Wistar rats were pretreated with 4 mg per kilogram per day ketorolac intramuscularly prior to receiving dorsal incisional wounds. The ketorolac treatment was continued and after 2 weeks the wounds were excised and separated with a tensiometer to measure mechanical properties. Breaking strength was directly measured, tensile strength was calculated, and collagen concentrations at the wound site were determined. A significant decrease in the mean breaking strength was seen in the ketorolac-treated animals when compared to controls. The ketorolac-treated animals had a mean tensile strength less than the controls, although this difference did not reach statistical significance. The mean collagen concentration of the ketorolac-treated wounds was significantly less than the untreated wounds. Use of ketorolac for just 1 week prior to surgery in rats produced a significant decrease in the breaking strength of their wounds. With the increasing use of ketorolac in surgical patients as well as the increasing use of oral NSAI drugs, more study of this effect is warranted.

Corneal sensitivity and burning sensation. Comparing topical ketorolac and diclofenac

OBJECTIVES

To compare the effect of topical 0.5% ketorolac tromethamine and 0.1% diclofenac sodium on human corneal sensitivity and to assess the intensity of burning sensation at specific intervals after drop instillation.

DESIGN AND SETTING

Double-masked parallel clinical study.

PATIENTS

Eleven women and 4 men (8 white, 4 Hispanic, 3 Asian), 22 to 60 years of age (mean [ +/- SD], 34 +/- 10 years).

INTERVENTIONS

Repeated instillation of either ketorolac and placebo or diclofenac and placebo at 5-minute intervals.

MAIN OUTCOME MEASURES

Assessment of corneal sensitivity before instillation, immediately after instillation, and after termination of drop application; and subjective evaluation of burning sensation by asking participants to rate burning on a scale ranging from 0 (none) to 3 (severe) after each drop application.

RESULTS

Both diclofenac (P < .01) and ketorolac (P < .01) decreased corneal sensitivity significantly, while the placebo had no measurable effect. After administration of additional drops over time, the effect of diclofenac and ketorolac increased. After termination of the drug instillation, corneal sensitivity returned to baseline significantly slower (P < .01) in participants receiving diclofenac than in those receiving ketorolac. Ketorolac (P = .01) and diclofenac (P < .05) were significantly more effective in whites than in nonwhites. Mean burning sensation was mild, and there was no statistically significant difference between the 2 drugs on this measure (P = .12).

CONCLUSIONS

The decrease in corneal sensitivity in normal human corneas is more pronounced and longer lasting with diclofenac than with ketorolac. Both drugs are well tolerated topically and may be useful for pain reduction after refractive corneal surgery.

Intrathecal ketorolac tromethamine produces analgesia after chronic constriction injury of sciatic nerve in rat

PURPOSE

The study compared analgesic efficacy of intrathecally administered ketorolac tromethamine (K) and morphine hydrochloride (M) (in equimolar doses) in the chronic neuropathic pain model, induced by chronic constriction injury (CCI) of the sciatic nerve in rat.

METHODS

Male Sprague-Dawley rats (n = 30) were anaesthetized with halothane and an intrathecal catheter was inserted to the mid-lumbar level of the spinal cord. On the 5th post-operative day, rats were anaesthetized with halothane and four ligatures were loosely applied around the right sciatic nerve. Seven days later, those animals were randomly divided into three groups and were injected with either saline, M (20 nmoles) or K (20 nmoles). Two pain responses (foot-withdrawal delay and hind paw elevation time) were measured on both sides using the radiant heat method. Further, thermal ("cold") allodynia was assessed by measuring of the total time of hind paw elevation in animals placed on the cold metal plate.

RESULTS

Twenty nmoles of M and K injected intrathecally produced decrease of differential pain score calculated for both measured responses (hind paw withdrawal and hind paw elevation), compared with saline injected animals (P < 0.05). The reduction in pain response produced by K was less (P < 0.05). than the reduction in pain response observed in the animals receiving intrathecal M. Measurement of cold allodynia revealed that the animals in M and K injected groups demonstrated decreases in the total hind paw elevation time, when compared with saline-injected animals (P < 0.05).

CONCLUSION

M and K produced hypoalgesia after intrathecal administration in rats with CCI, with M being more potent than K at an equimolar dose range. The analgesic effect of K was equal to equimolar doses of M for alleviation of cold allodynia.

Efficacy of ketorolac tromethamine and extrapleural intercostal nerve block on post-thoracotomy pain. A prospective, randomized study

BACKGROUND

Post-thoracotomy pain causes severe impairment of the respiratory function. Epidural analgesia is effective in the treatment of post-thoracotomy pain but may give rise to significant side-effects. Other low-risk and cost-effective analgesic treatments are therefore required.

METHODS

Thirty male patients who had undergone pulmonary lobectomy entered a prospective, randomized trial to evaluate the efficacy of ketorolac tromethamine (Group 2) and extrapleural intercostal nerve block (Group 3) with intermittent low-dose bupivacaine. Objective and subjective assessment was carried out at 8, 16, 24 and 48 hours postoperatively.

RESULTS

There were no significant differences between Groups 1 (control group) and 2. Vital capacity was significantly lower in Group 3 (p<0.05) than in Group 1 after 16 hours. Forced Vital Capacity was significantly higher in Group 2 than in Group 3 after 16 and 24 hours (p<0.05). Peak expiratory flow was also significantly better in Group 2 than in Group 3 after 16 hours (p<0.05). On-demand opioid consumption was significantly lower in Group 2 (p<0.001) and Group 3 (p<0.05). No side-effects were observed.

CONCLUSIONS

Ketorolac tromethamine was effective in the treatment of post-thoracotomy pain. Extrapleural intercostal nerve block allowed a significant reduction in the consumption of opioids. These analgesic techniques could be useful as low-risk, cost-effective and reproducible treatments when more effective techniques, such as epidural analgesia, are contraindicated.

Contact lens induced conjunctivitis: a model of human ocular inflammation

PURPOSE

To demonstrate the usefulness of contact lens induced conjunctivitis as a model of human ocular inflammation and to evaluate the effect of antiallergic eyedrops on this model.

METHODS

We recruited 40 subjects with contact lens induced conjunctivitis. Half were treated with ketorolac tromethamine (KT), and half with iodoxamide tromethamine (LT). Signs, symptoms, contact lens wearing time, and wearing time until discomfort developed were evaluated at baseline, day 7, and day 14.

RESULTS

The group receiving LT showed improvement of symptoms 7 days after beginning the study (P = 0.016), and both the LT and KT groups showed improvement from baseline on day 14 (P = 0.001 and P = 0.004, respectively). Signs improved for both the KT group (P = 0.011) and the LT group (P = 0.043) on day 7 and day 14 (P = 0.033 and P = 0.007, respectively). Mean contact lens wearing time improved on day 14 for the group treated with KT (P = 0.001).

CONCLUSIONS

Contact lens induced conjunctivitis appears to be a useful model of human ocular inflammation. Both antiallergics KT and LT improve contact lens tolerance in subjects with contact lens induced conjunctivitis. Two weeks of treatment may be required to demonstrate therapeutic benefits of antiallergic drops.

The effect of ketorolac on microvascular thrombosis in an experimental rabbit model

This study was undertaken to evaluate the effect of ketorolac (Toradol), a potent cyclooxygenase inhibitor used for postoperative pain, on microvascular thrombosis in an established thrombosis model. Bilateral 3-mm arterial inversion grafts (n = 66) were constructed in the femoral arteries of New Zealand White rabbits. ALZET (ALZA Corporation, Palo Alto, Calif.) osmotic pumps were implanted in the external jugular veins for drug delivery. The blinded protocol called for the experimental animals to receive intravenous doses of ketorolac of 1.72 mg/kg per day (group 1) or 3.44 mg/kg per day (group 2), while control animals received equivalent volumes of saline. Patency was assessed at 7 days. Whereas 52 percent (13 of 25) of control vessels remained patent, 70 percent (14 of 20) and 86 percent (18 of 21) of group 1 and group 2 vessels, respectively, were patent at 1 week. This decrease in microvascular thrombosis with delivery of ketorolac was statistically significant (p = 0.0094). Ketorolac, at experimental doses approximating 9 and 18 mg IV q6h in a 70-kg man, demonstrated a statistically significant reduction in microvascular thrombosis. This study supports its use in clinical microvascular surgery.

Asthma caused by topical application of ketorolac

BACKGROUND

Ketorolac tromethamine 0.5 percent ophthalmic solution is a widely used nonsteroidal anti-inflammatory drug (NSAID) in ophthalmology. Ketorolac eye drops have not been implicated previously as a cause of NSAID-induced asthma.

STUDY DESIGN

A patient with severe asthma after topical application of ketorolac is described. The current ophthalmic indications for topical application of ketorolac and reported hypersensitivity reactions with systemic use of ketorolac are reviewed.

RESULTS

A 44-year-old woman with chronic asthma, rhinosinusitis, and nasal polyps inadvertently was given ketorolac to be applied topically. After applying the first dose of ketorolac, an exacerbation of her asthma developed, necessitating hospital admission.

CONCLUSIONS

Topical application of ketorolac is safe in the vast majority of ophthalmology patients. However, NSAID eye drops should not be prescribed for patients with aspirin or NSAID allergy or the combination of asthma and nasal polyps unless the patient is known to tolerate aspirin without trouble.

Interaction of low molecular weight heparin with ketorolac

Postoperative patients may receive ketorolac, a nonsteroidal antiinflammatory drug that inhibits platelet function, for analgesia and may receive low-molecular-weight heparin (LMWH) for thrombosis prevention. We investigated whether the combination of these two agents increases blood loss in a rabbit model of hemostasis. In a randomized, blinded study, animals received either intramuscular ketorolac (0.5 mg/kg or 1.0 mg/kg) and subcutaneous saline solution, subcutaneous LMWH (100 U/kg) and intramuscular saline solution, ketorolac (0.5 mg/kg or 1.0 mg/kg) and subcutaneous LMWH (100 U/kg), or intramuscular and subcutaneous saline solution given 30 minutes before ear incision and measurement of blood loss. Collagen-induced platelet aggregation was examined and anti-Xa levels were determined by using a chromogenic substrate method. As compared with results in saline-treated controls, blood loss was significantly increased in animals receiving ketorolac in a dose of 1.0 mg/kg but not in those treated with 0.5 mg/kg. The addition of LMWH did not further increase blood loss above that observed with either dose of ketorolac alone. Platelet aggregation was inhibited by both doses of ketorolac. The anti-Xa levels in the LMWH-treated animals were comparable to those measured in patients receiving these agents for prophylaxis (0.09 to 0.13 U/ml). We conclude that in the rabbit model, LMWH does not augment ketorolac-associated bleeding when both agents are used in doses comparable to those given to human patients.

Intravenous ketorolac tromethamine worsens platelet function during knee arthroscopy under spinal anesthesia

Ketorolac prolongs bleeding time and inhibits platelet aggregation and platelet thromboxane production in healthy, awake volunteers. However, platelet function was recently shown not to worsen after ketorolac was given during general anesthesia. The purpose of this study was to investigate platelet function changes during a standardized spinal anesthetic and surgery, as well as after a single intraoperative dose of intravenous (IV) ketorolac. The study comprised 30 ASA physical status I patients undergoing spinal anesthesia for knee arthroscopy. Subjects were randomized to receive either ketorolac 60 mg IV 15 min after skin incision or placebo IV. Platelet function testing consisted of an Ivy bleeding time, platelet aggregometry with adenosine diphosphate (ADP) and collagen, thromboelastography (TEG), and serum thromboxane B2 (TxB2) assays. Platelet function testing was performed: 1) 15 min prior to the performance of spinal anesthesia; 2) 10 min after surgical skin incision; and 3) 45 min after administration of study drug. The placebo group demonstrated no changes in any platelet function variable during spinal anesthesia and surgery relative to preoperative values. The ketorolac group, however, demonstrated a significant increase in bleeding time from postincision to poststudy drug data points (213 +/- 60s to 275 +/- 85s, mean +/- SD; P < 0.01). Further, platelet aggregometry to collagen was diminished in the ketorolac group from preoperative to poststudy drug data points (90.8% +/- 7.6% to 60.5% +/- 32.5%; P < 0.01). Platelet aggregometry with ADP, however, was unchanged in the ketorolac group. Platelet TxB2 production decreased dramatically in the ketorolac group from preoperative to poststudy drug data points (157.2 +/- 129.4 to 0.3 +/- 0.3 ng/mL; P < 0.01). Platelet function does not appear to be accentuated during spinal anesthesia as it is during general anesthesia. Unlike during general anesthesia, platelet function during spinal anesthesia is impaired, with respect to bleeding time and platelet aggregometry to collagen, by a single intraoperative dose of IV ketorolac.

A critical look at ocular allergy drugs

Topical ocular allergy drugs are indicated for the treatment of allergic conjunctivitis after more conservative measures have been employed. Antihistamines, vasoconstrictors, nonsteroidal anti-inflammatory drugs, mast cell stabilizers and corticosteroids are available. Levocabastine and ketorolac tromethamine are new drugs for the treatment of allergic conjunctivitis. Lodoxamide is currently indicated only for the treatment of vernal keratoconjunctivitis, although treatment efficacy has been demonstrated in patients with giant papillary conjunctivitis and atopic keratoconjunctivitis. As a general rule, topical ocular allergy drugs are well tolerated by most patients except for transient stinging and burning on instillation. Ocular steroids should be reserved for severe cases and should be prescribed by an ophthalmologist, who can monitor the patient for possible ocular side effects.

Intraoperative ketorolac has an opioid-sparing effect in women after diagnostic laparoscopy but not after laparoscopic tubal ligation

Ketorolac tromethamine (Toradol) is a parenteral, nonsteroidal antiinflammatory drug that is being extensively used to provide postoperative analgesia. This study evaluated whether intraoperative ketorolac would act synergistically with fentanyl to decrease postoperative analgesic requirements in outpatients undergoing gynecologic procedures. The patients studied were adult ASA physical status I or II females scheduled for diagnostic laparoscopy (DL) (n = 80) or laparoscopic tubal ligation (TL) (n = 46). Each patient received fentanyl 2 micrograms/kg intravenously (i.v.) before induction, followed by a standardized propofol anesthetic and 2 mL of saline or ketorolac 60 mg i.v. in a randomized double-blind fashion 30 min before the anticipated end of the operative procedure. Patients were assessed for postoperative pain via a 10-cm visual analog scale (VAS) (0 = no pain; 10 = severe pain) before analgesic treatment in the postanesthesia care unit (PACU). Severe postoperative pain (VAS or 5 or more) was treated with incremental doses of fentanyl, 25-50 micrograms i.v. by a blinded PACU nurse. Ibuprofen or acetaminophen with codeine was administered for pain control once the patient tolerated oral medications. This study showed that intraoperative ketorolac (60 mg i.v.) with fentanyl (2 micrograms/kg i.v.) administered at the induction of anesthesia resulted in significant opioid sparing and a diminution in pain in the DL sample but not in the TL sample. The analgesic regimen was also associated with a lower incidence of nausea and vomiting and resulted in earlier discharge, which was not seen after TL. These results demonstrate that pain after TL is far greater than that after DL, which suggests that these procedures should be considered separately when designing analgesic regimens.

Does patient-controlled analgesia achieve better control of pain and fewer adverse effects than intramuscular analgesia? A prospective randomized trial

OBJECTIVE

To compare three analgesic regimens in patients undergoing colon resection: patient-controlled morphine sulfate analgesia (PCA), intramuscular (IM) morphine, and IM ketorolac tromethamine.

DESIGN

Prospective randomized case series.

SETTING

Rural, private teaching hospital.

PATIENTS

All patients (307) scheduled to undergo a major colon resection between January 1, 1992, and December 31, 1993, were eligible to participate. Of these, 10 (3%) were missed in the screening process, 132 (43%) declined participation, 73 (24%) were excluded, and 92 (30%) were enrolled and randomly assigned to a treatment group.

INTERVENTIONS

Ninety-two patients were enrolled in the study. Two patients never received the medication to which they were assigned, owing to administrative error; their data was not analyzed. Of the remaining patients, 31 were randomized to the PCA morphine group, 31 were randomized to the IM morphine group, and 28 were randomized to the IM ketorolac group. The randomly assigned drug was first administered in the post-anesthesia care unit. On arrival on the postoperative ward, the patient was asked to rate his or her pain using both a numerical rating scale and a visual analog scale at 30 minutes; 1, 2, 3, 4, and 6 hours after arrival on the ward; and every 4 hours throughout the first 5 postoperative days. The Mini-Mental State Examination (MMSE) was administered the day before surgery and then daily for the first 5 postoperative days. The first day the patient passed flatus after surgery was also recorded.

MAIN OUTCOME MEASURES

The end points analyzed were adverse effects, duration of postoperative ileus, degree of pain control, length of hospitalization, and development of postoperative confusion as measured on serial MMSEs.

RESULTS

Only two patients, both in the PCA group, reported adverse effects; neither required a change in analgesia group. Significantly more patients assigned to IM ketorolac broke protocol and required alternative analgesia than did patients in the morphine groups (32% ketorolac vs 16% IM morphine and 0% PCA). The ketorolac group had a significantly shorter duration of ileus than either morphine group (P<.0l). The ketorolac group also had significantly lower pain scores (P<.04) and less postoperative confusion than the morphine groups (P<.03), although these results are limited by missing values. The ketorolac group had a significantly shorter length of stay than either morphine group (P<.01), while there was no significant difference between the morphine groups (P=.75).

CONCLUSIONS

While it appears that ketorolac provides a better postoperative course than either IM or PCA morphine in terms of pain control, postoperative confusion, length of stay, and duration of ileus, 18% of our patients assigned to ketorolac required additional analgesia, and there was a strong patient preference for PCA. Most patients should probably be managed with PCA narcotics, but the addition of ketorolac might reduce narcotic dose and resultant adverse effects. Those patients particularly prone to adverse effects should receive primarily ketorolac.

Effect of benzalkonium chloride/EDTA on the ocular bioavailability of ketorolac tromethamine following ocular instillation to normal and de-epithelialized corneas of rabbits

This study was designed to examine the effect of benzalkonium chloride/ethylenediaminetetraacetic acid (BAK/EDTA) on the ocular bioavailability (Focular) of ketorolac tromethamine after ocular instillation to normal and de-epithelialized corneas of rabbits both in vitro and in vivo. The in vitro Focular of the formulations was measured in flow-through perfusion chambers. For in vivo studies, a 35 microL dose of 0.5% ketorolac tromethamine with or without BAK/EDTA was instilled into rabbit eyes with intact or de-epithelialized corneas. At 0.5, 1, 2, 4, 6, and 8 h postdose, rabbits were euthanized, and the corneas and aqueous humor were collected from both eyes. The ketorolac concentrations from both in vivo and in vitro samples were quantified by reversed-phase high-performance liquid chromatography. The in vitro study results indicated that BAK/EDTA statistically significantly increased the Focular of ketorolac through de-epithelialized corneas but not through intact corneas. The in vivo study results showed that BAK/EDTA had no effect on the Focular of ketorolac in rabbits with intact corneas, based on the values of the area under the aqueous humor concentration versus time curves (AUC0-6h) of ketorolac. As expected, de-epithelialization of the corneas produced a faster and greater ocular absorption of ketorolac as evidenced by the smaller Tmax and larger AUC values compared to those for the intact corneas in vivo. However, BAK/EDTA decreased the ocular absorption of ketorolac in rabbits with de-epithelialized corneas. The half-lives (t 1/2) of ketorolac in corneal tissue and aqueous humor were longer in rabbits with intact corneas than those in rabbits with de-epithelialized corneas. In conclusion, the in vivo Focular of ketorolac was not altered by BAK/EDTA in rabbits with intact corneas, but it was decreased by BAK/EDTA in rabbits with de-epithelialized corneas. Therefore, the formulation with ketorolac alone may be better as a post-operative ocular analgesic.

Intraocular penetration of periocular ketorolac and efficacy in experimental uveitis

PURPOSE

To determine in rabbits whether periocular injection of ketorolac tromethamine effectively delivers the drug to the eye and, if so, whether this is efficacious in the treatment of experimental uveitis.

METHODS

Ketorolac was administered by anterior subconjunctival injection, posterior periocular injection, intramuscular injection, or topical eye drops. The aqueous and vitreous were assayed for ketorolac. Anterior subconjunctival and topical ketorolac were compared to control as well as topical and anterior subconjunctival steroid treatments in uveitis induced by the intravitreal injection of tumor necrosis factor.

RESULTS

Anterior subconjunctival injection led to high, though short-lived, levels of drug in the aqueous and vitreous. Posterior periocular injection led to much lower levels. Topical dosing led to relatively low aqueous and undetectable vitreous levels. No ocular levels were detected after intramuscular dosing. All tested antiinflammatory treatments were similarly effective in controlling uveitis.

CONCLUSIONS

Anterior subconjunctival injection of ketorolac produced high intraocular concentrations of drug and was beneficial in controlling the inflammation in this animal model of uveitis.

Comparative effects of three doses of intravenous ketorolac or morphine on emesis and analgesia for restorative dental surgery in children

PURPOSE

The optimal dose of intravenous ketorolac tromethamine (ketorolac), a non-steroidal anti-inflammatory drug has not been determined in children. There are only limited published data on the use of intravenous ketorolac for paediatric analgesia. This study compares the analgesic and emetic effect of three different doses of ketorolac with morphine in paediatric dental surgical out-patients.

METHODS

Following institutional approval and parental consent, 120 ASA I or II children, age 2-10 yr were randomized to four groups and received ketorolac 0.75, 1.0, and 1.5 mg.kg-1 or morphine 0.1 mg.kg-1 iv at induction of a standardized anaesthetic. At 15 and 30 min after arrival in the recovery room a blinded observer assessed pain using the Objective Pain Score (OPS). Twenty-four hours after surgery a telephone interview was carried out with a parent at home.

RESULTS

There were no differences in demographic data, anaesthesia time, recovery and day-care unit time, OPS and postoperative analgesic requirements in the four groups. Postoperative vomiting in the first 24 hr occurred more frequently in the morphine group than in the other groups (P < 0.0166). No patient had excessive surgical bleeding.

CONCLUSIONS

Ketorolac, in all doses studied (0.75, 1.0 and 1.5 mg.kg-1) was as effective an analgesic as morphine 0.1 mg.kg-1 given intravenously at induction to children having restorative dental surgery. Its use was associated with a significant reduction in the incidence of postoperative vomiting.

Parenteral ketorolac and risk of gastrointestinal and operative site bleeding. A postmarketing surveillance study

OBJECTIVE

To evaluate the risk of gastrointestinal and operative site bleeding associated with the use of parenteral ketorolac tromethamine.

DESIGN

Postmarketing surveillance inception cohort study.

SETTING

A total of 35 hospitals throughout the Philadelphia, Pa, region, 1991 to 1993.

PATIENTS

Patients administered 10,272 courses of parenteral ketorolac therapy were compared with patients administered 10,247 courses of a parenteral opiate who were matched to the ketorolac patients by hospital, admitting service, and date of initiation of study drug.

MAIN OUTCOME MEASURES

Medical records were reviewed for demographics, medical history, doses and duration of study drug, various aspects of the hospital course including surgery and concomitant medications, and adverse events.

RESULTS

The multivariate adjusted odds ratio (OR) comparing ketorolac with opiates for gastrointestinal bleeding was 1.30 (95% confidence interval [CI], 1.11 to 1.52); for operative site bleeding, the OR was 1.02 (95% CI, 0.95 to 1.10). The OR was elevated further in subjects 75 years of age or older for both gastrointestinal bleeding (OR = 1.66; 95% CI, 1.23 to 2.25) and operative site bleeding (OR = 1.12; 95% CI, 0.94 to 1.35). A dose-response relationship was evident between average daily ketorolac dose and both gastrointestinal bleeding and operative site bleeding (trend test P < .001 for both). When analgesic therapy lasted 5 or fewer days, ketorolac was associated with only a small increased risk of gastrointestinal bleeding (OR = 1.17; 95% CI, 0.99 to 1.30); when therapy was prolonged beyond 5 days, the OR was 2.20 (95% CI, 1.36 to 3.57). The association of ketorolac with operative site bleeding was not affected by duration of therapy.

CONCLUSIONS

The overall associations between ketorolac use and both gastrointestinal bleeding and operative site bleeding are small. However, the risk associated with the drug is larger and clinically important when ketorolac is used in higher doses, in older subjects, and for more than 5 days. Improving physicians' prescribing practices by limiting the dose and duration of ketorolac use, especially in the elderly, should enhance its overall risk-benefit balance.

Effect of pretreatment with ketorolac tromethamine on post-operative pain following periodontal surgery

A double-blind, randomized, single-dose clinical trial to evaluate the analgesic efficacy of preoperative ketorolac tromethamine administration on periodontal postoperative pain was designed. One group received 20 mg ketorolac immediately before periodontal flap surgery, and the other group received placebo. Naproxen sodium was allowed postoperatively as rescue medication. The visual analog scale was used to estimate pain. Postoperative pain was assessed hourly for the first 10 h on the day of surgery, and 4 x daily on the 1st and 2nd postsurgical days. Timing and dose of rescue analgesic remedication were also recorded. Results indicated that preoperative treatment with ketorolac significantly reduced initial pain intensity and delayed the onset of postoperative pain as compared to placebo. Incidence and amount of naproxen consumption was similarly small in both ketorolac- and placebo-treated groups. No adverse reactions related to preoperative medication were observed.