Current concepts in the pathogenesis of Alzheimer's disease

Alzheimer's disease (AD) affects a large proportion of the increasingly aging population of this country, with prevalence rates as high as 47% for those >85 years old and a total annual cost approaching $70 billion. There is no currently validated test for detection of dementia of the Alzheimer type (DAT). Because of this and the insidious onset of the disease, the diagnosis may be missed by primary care physicians. Cerebral extracellular beta-amyloid deposition as senile plaques and intraneuronal neurofibrillary tangles appear to represent critical processes in the development of AD; however, whether and the extent to which these may also occur in nondemented aging is uncertain. Tangles occur primarily in medial temporal lobe structures (hippocampus, entorhinal cortex, and amygdala), and tangle density correlates with dementia severity. Plaques are diffusely distributed throughout the cerebral cortex, and are the neuropathologic hallmark of the disease. Aging is the primary risk factor for AD. After controlling for differential life expectancy, female sex still appears to be an additional risk factor. There may be a genetic component, in some cases based on family and twin studies. Allelic variation in the apolipoprotein E (Apo E) gene located on chromosome 19 represents another important risk factor. However, the diversity of gene mutations apparently responsible for the various forms of AD suggest that the disease is genetically heterogeneous. AD may be conceptualized as an imbalance between neuronal injury and repair. Oxygen free radicals may be involved in the cross-linking process of beta-amyloid aggregation, and antioxidants may represent a potential intervention. There may be a role for heavy metals in the pathogenesis of AD, but this remains controversial. Work continues toward possibly a cure or prevention, but more likely palliation, of AD, and the results of trials of anti-inflammatory agents, estrogen, and antioxidant therapy are anticipated in the near future.

Preoptic area infusions of morphine disrupt--and naloxone restores--parental-like behavior in juvenile rats

As in the adult lactating female, opioids disrupt (and naloxone restores), parental behavior in juvenile rats (approximately 25 days of age). Because the preoptic area regulates the display of parental behavior in lactating females, we examined its parental behavior role in the juvenile rat. At 21 days of age, juvenile rats were implanted with bilateral cannulae aimed at the preoptic area using a modified Kopf stereotaxic and extrapolating from a developing-rat brain atlas [58], and divided into two groups: Initiation and maintenance. On day 25, the initiation group received bilateral infusions of either morphine (0.50 microgram), saline (0.25 microliter), or morphine plus naloxone (0.25 microgram). Thirty minutes later, they were exposed to three 1-6-day-old pups; the maintenance group was exposed to pups until they displayed 2 consecutive days of parental behavior, then infused. Morphine disrupted parental behavior in both the initiation and Maintenance groups, and naloxone restored the behavior to control/ saline levels. Parental behavior in the juvenile animal of both sexes, therefore, is under opioid regulation that parallels the adult female.

Hemodynamic effects of intravenous somatostatin administered in the postoperative period

OBJECTIVE

To evaluate the hemodynamic effects of intravenous somatostatin administration in patients during the early postoperative period.

DESIGN

Prospective, case-controlled trial.

SETTING

Postanesthesia care unit.

PATIENTS

Ten postoperative, noncirrhotic, American Society of Anesthesiologists physical status II patients, after resection of nonsecretory (i.e., non-neuroendocrine) tumors. No patient received any vasoactive medication perioperatively.

INTERVENTIONS

Three hours after the end of surgery, normal saline or somatostatin was intravenously administered in two phases: a) in phase 1, patients received a 20-mL bolus of normal saline within 1 min, followed by a continuous infusion of 20 mL of normal saline for the next 30 mins. Patients were left undisturbed for the subsequent 30 mins. b) in phase 2, patients received somatostatin (3.5 micrograms/kg, 20-mL bolus) over 1 min, followed by a continuous infusion of somatostatin (3.5 micrograms/kg/hr) for 72 hrs.

MEASUREMENTS AND MAIN RESULTS

Anesthesia was managed according to a prospectively designed protocol. Patients' hemodynamic profiles and pressure waveforms were recorded immediately before the bolus injections of normal saline and somatostatin, and at every minute thereafter for 30 mins. Bolus doses of somatostatin produced a transient, nonsignificant decrease in heart rate, along with short-lived increases in systolic arterial pressure, diastolic arterial pressure, systolic pulmonary arterial pressure, diastolic pulmonary arterial pressure, and central venous pressure.

CONCLUSION

Bolus intravenous somatostatin administered postoperatively after tumor resection in patients produced transient cardiovascular changes that were not sustained during a subsequent continuous infusion.

Cost considerations in patient-controlled analgesia

Patient-controlled analgesia (PCA) is the use of a portable infusion pump activated by the patient to inject an analgesic drug intravenously, subcutaneously or epidurally. PCA permits a patient to deliver a small bolus of opioid to achieve prompt relief without over sedation. Use of PCA for pain management is increasing in hospitals and home settings, largely because it can provide equivalent or better analgesia than conventional methods, and patients are more satisfied with its use. This article reports on studies published between January 1984 and December 1995 which considered cost aspects of PCA. Most studies compared the direct costs of administering PCA with the cost of other forms of drug delivery, usually intramuscular injections. A few studies have included indirect costs such as length of stay and adverse effects associated with the use of PCA. The research on cost considerations of PCA is dominated by case reports, descriptive studies and poorly designed quasi-experimental studies. The most complete and well conducted studies usually have included only drug, equipment and labour costs. Only 6 randomised controlled trials were reported, all of which were conducted on postoperative patients. The cost effectiveness of PCA for pain management is an unresolved question because of the variability in methods used to determine costs and expenses, the different settings and patient populations in which PCA is applied, the different means to organise its management and the fact that it is a rapidly evolving technology during an era of changing reimbursement practices. There is substantial variation in the cost of drugs used in PCA and in the devices themselves, which influences the comparison of costs across studies. Also, researchers do not include the full scope of costs associated with the use of PCA in comparison with conventional drug delivery methods and some do not measure the level of pain relief achieved. Of the few complete and well designed published studies found, PCA was reported to produce superior analgesia at a higher cost than conventional intramuscular therapy in 3 studies, but to be more costly and produce less pain relief than intramuscular therapy in 1 study. There is a pressing need for cost-effectiveness, cost-utility and cost-benefit analyses to determine the appropriate clinical and cost circumstances for the use of PCA.

Back pain among echocardiographers

OBJECTIVE

By having to adopt unnatural postures, echocardiographers place themselves at risk of back injury. The present study sought to document the incidence and severity of back pain among echocardiographers, and to identify personal, lifestyle and occupational characteristics that may predict risk of back pain.

DESIGN

A questionnaire concerning occupational, personal, and lifestyle characteristics, as well as the extent and severity of back pain was completed and returned by 183 echocardiographers.

RESULTS

The standard echocardiography examination position of "machine on the left, patient on the right, and transducer held in the right hand" (used by 66% of respondents) greatly increased the risk of back pain (odds ratio (OR) = 4.9; 95% confidence interval (95% CI) = 1.49-16.4). Echocardiographers with more than 11 years experience in the field were also at risk of back pain (OR) = 3.4; 95% CI = 0.97-11.6). The intensity of back pain was strongly associated with the amount of time spent on echocardiography examinations (P = 0.035), limitation of lifestyle (P < or = 0.001), and interference with work (P < or = 0.001). There was a significantly higher relative risk of back pain for the respondents whose job involved frequent or occasional lifting compared with nonlifters (P = 0.01; OR = 4.8, 95% CI = 1.25-18.7). At least some limitation of lifestyle from back pain was reported by 56% of the respondents.

CONCLUSIONS

There is a high incidence of back pain among echocardiographers, and specific tasks and activities increase the risk of back pain. Further research should focus on preventative measures and optimum work station designs that may serve as a guide to echocardiography departments.

Reliability of the Washington University Road Test. A performance-based assessment for drivers with dementia of the Alzheimer type

OBJECTIVE

To assess the reliability and stability of a standardized road test for healthy aging people and those with dementia of the Alzheimer type (DAT).

DESIGN

A prospective study involving patients with DAT and age-matched healthy controls in which subjects' driving performance was evaluated by several raters in an initial and a follow-up road test.

SETTING

Urban medical school and urban highways and streets.

SUBJECTS

A convenience sample of 58 controls, 36 subjects with very mild DAT, and 29 subjects with mild DAT.

RESULTS

Analysis of road test ability of controls (2 subjects [3%] failed the test), very mild DAT subjects (7 subjects [19%] failed), and mild DAT subjects (12 subjects [41%] failed) disclosed a significant association between driving performance and dementia status (chi 2[4] = 20.65 [N = 123]; P < .001; Kendall tau-b = 0.306). Interrater reliability for assessment of driving performance ranged from kappa = 0.85 to 0.96. One-month test-retest stability on the road test was 0.76 (quantitative scoring) and 0.53 (clinical judgment).

CONCLUSIONS

Dementia adversely affects driving performance even in its mild stages, although some persons with DAT seem to drive safely for some time after disease onset. A traffic-interactive, performance-based road test that examines cognitive behaviors provides an accurate and reliable functional assessment of driving ability.

Environmental cueing may effect performance on a road test for drivers with dementia of the Alzheimer type

This paper examines the impact of environmental cueing on a road test for persons with dementia of the Alzheimer type (DAT). In an earlier study, we demonstrated the reliability and stability of the Washington University Road Test in a sample of 58 healthy elderly controls and 65 subjects with DAT. We found that dementia adversely affects driving performance even in its mild stages. Here were elaborate on the results of a follow-up road test conducted 1 month after the baseline test (n = 63) explore possible reasons why the stability of the follow-up road test was lower than expected. We conclude that environmental cueing may affect performance on a road test in DAT.

Motor vehicle crashes and drivers with DAT

An increasing number of drivers with dementia is expected over the next few decades. From a public safety standpoint, there is concern that these drivers also will have an increased risk for motor vehicle crashes. This paper examines recent studies on motor vehicle crashes experienced by drivers with dementia and/or dementia of the Alzheimer type (DAT). These studies were analyzed for their common findings, strengths, and limitations. Many studies reveal an increased crash rate for drivers with DAT compared with nondemented older drivers. Studies suggest that 50% of DAT drivers stop driving within 3 years of the onset of disease, the risk for a motor vehicle crash increases with the duration of driving after disease onset, males are at increased risk for crashes, dementia severity does not correlate with risk for a crash, and additional medical conditions may further contribute to crash risk. Areas of focus for future studies in this field are discussed.

Pain relief after knee arthroscopy: intra-articular morphine, intra-articular bupivacaine, or subcutaneous morphine?

BACKGROUND AND OBJECTIVES

This investigation was undertaken to compare analgesic effects, side effects, and requirements for supplemental analgesic therapy after knee arthroscopy in patients given intra-articular (IA) or subcutaneous (SC) morphine, intra-articular bupivacaine, or placebo.

METHODS

In a randomized, double-blind controlled trial, 112 patients, 14-65 years old each received two solutions, one SC and the other IA. Group IAM (n = 30) received 10 mg IA morphine in 20 mL normal saline plus 1 mL of SC normal saline Group IAB (n = 27) received 20 mL IA bupivacaine 0.5% with IA epinephrine plus 1 mL SC normal saline Group SCM (n = 26) received 20 mL IA normal saline plus 10 mg SC morphine in 1 mL. Group P (n = 29) received 20 mL IA normal saline plus 1 mL SC normal saline. Pain was evaluated on arrival in the postanesthesia care unit (PACU), and 30, 45, 60, 90, and 120 minutes afterwards. If pain exceeded 4/10 on a visual analog pain scale in the PACU, 30 mg intravenous ketorolac was given, and if pain persisted, 0.4 mg hydromorphone was added every 7 minutes. After PACU discharge, patients whose pain exceeded 4/10 received oral ketorolac 10 mg every 6 hours; oral acetaminophen plus codeine was added every 4 hours if pain still exceeded 4/10. Analgesic requirements, along with visual analog pain score, sedation, and nausea were recorded every 6 hours for 72 hours.

RESULTS

All three active (nonplacebo) pain treatments provided good pain control in the PACU. Side effects were similar in all groups. The placebo group had higher pain scores at 120 minutes (R = .02), higher supplemental analgesic requirements at 60 minutes (P = .04) and 90 minutes (P = .02) and the highest amount of total opioid rescue dose (P = .04). Patients in groups IAB and P had higher visual analog pain scores at 6 hours (P = .04) and 30 hours (P = .049) than those in Groups IAM and SCM.

CONCLUSION

A single 10-mg dose of morphine given either IA or SC provides better and longer-lasting postoperative pain relief after knee arthroscopy than 20 mL IA bupivacaine 0.5% with epinephrine.

Characterization of Ha-ras, N-ras, Ki-Ras4A, and Ki-Ras4B as in vitro substrates for farnesyl protein transferase and geranylgeranyl protein transferase type I

Ras proteins are small GTP-binding proteins which are critical for cell signaling and proliferation. Four Ras isoforms exist: Ha-Ras, N-Ras, Ki-Ras4A, and Ki-Ras4B. The carboxyl termini of all four isoforms are post-translationally modified by farnesyl protein transferase (FPT). Prenylation is required for oncogenic Ras to transform cells. Recently, it was reported that Ki-Ras4B is also an in vitro substrate for the related enzyme geranylgeranyl protein transferase-1 (GGPT-1) (James, G. L., Goldstein, J. L., and Brown, M. S. (1995) J. Biol. Chem. 270, 6221-6226). In the current studies, we compared the four isoforms of Ras as substrates for FPT and GGPT-1. The affinity of FPT for Ki-Ras4B (Km = 30 nM) is 10-20-fold higher than that for the other Ras isoforms. Consistent with this, when the different Ras isoforms are tested at equimolar concentrations, it requires 10-20-fold higher levels of CAAX-competitive compounds to inhibit Ki-Ras4B farnesylation. Additionally, we found that, as reported for Ki-Ras4B, N-Ras and Ki-Ras4A are also in vitro substrates for GGPT-1. Of the Ras isoforms, N-Ras is the highest affinity substrate for GGPT-1 and is similar in affinity to a standard GGPT-1 substrate terminating in leucine. However, the catalytic efficiencies of these geranylgeranylation reactions are between 15- and 140-fold lower than the corresponding farnesylation reactions, largely reflecting differences in affinity. Carboxyl-terminal peptides account for many of the properties of the Ras proteins. One interesting exception is that, unlike the full-length N-Ras protein, a carboxyl-terminal N-Ras peptide is not a GGPT-1 substrate, raising the possibility that upstream sequences in this protein may play a role in its recognition by GGPT-1. Studies with various carboxyl-terminal peptides from Ki-Ras4B suggest that both the carboxyl-terminal methionine and the upstream polylysine region are important determinants for geranylgeranylation. Furthermore, it was found that full-length Ki-Ras4B, but not other Ras isoforms, can be geranylgeranylated in vitro by FPT. These findings suggest that the different distribution of Ras isoforms and the ability of cells to alternatively process these proteins may explain in part the resistance of some cell lines to FPT inhibitors.

Dementia and driving: an attempt at consensus

The number of older drivers in Sweden will be rapidly increasing during the next decades. A possible relationship exists between the increased relative crash risk of older drivers and the prevalence of age-related diseases such as dementia. However, a clear-cut policy for evaluating driving competence in demented persons is still lacking. In recognition of this fact, the Swedish National Road Administration invited a group of researchers to formulate a consensus on the issue of driving and dementia. This consensus document is aimed at providing primary care physicians with practical advice concerning the assessment of cognitive status in relation to driving. Suggestions are based on a review of existing research and discuss the use of general and driving-specific sources of information available to the physician. Consensus was reached on the statement that a diagnosis of moderate to severe dementia precludes driving and that certain individuals with mild dementia should be considered for a specialized assessment of their driving competence.

Differential effect of central versus parenteral administration of morphine sulfate on regional concentrations of reduced glutathione in rat brain

Prior studies in rodents have shown significant depletion of reduced glutathione (GSH) in peripheral organs following acute systemic or central administration of opioids. However, little information exists on whether opioid administration affects concentrations of brain GSH. Recently, clinical observations have indicated acute declines of GSH concentrations in the cerebrospinal fluid of cancer patients after acute intracerebroventricular (ICV) morphine which may contribute to the development of organic behavioral brain syndromes associated with central opioid analgesia. Collectively these data led us to investigate the affect of acute systemic and central morphine on regional concentrations of GSH in rat brain. Systemic morphine had no effect on GSH concentrations in selected brain areas. In contrast, ICV morphine resulted in selective GSH depletion in the caudate nucleus, consistent with concurrent excitatory locomotive behavior. This change may have reflected morphine-induced oxidative stress together with increased metabolic activity within the extrapyramidal system.

Antitumor 8-chlorobenzocycloheptapyridines: a new class of selective, nonpeptidic, nonsulfhydryl inhibitors of ras farnesylation

Ras farnesylation by farnesyl protein transferase (FPT) is an intracellular event that facilitates the membrane association of the ras protein and is involved in the signal transduction process. FPT inhibition could be a novel, noncytotoxic method of treating ras dependent tumor growth. We report here three structural classes of 8-chlorobenzocycloheptapyridines as novel, nonpeptidic, nonsulfhydryl FPT inhibitors having antitumor activity in mice when dosed orally. We discuss structural and conformational aspects of these compounds in relation to biological activities as well as a comparison to the conformation of a bound tetrapeptide FPT inhibitor.

Ras oncoprotein inhibitors: the discovery of potent, ras nucleotide exchange inhibitors and the structural determination of a drug-protein complex

The nucleotide exchange process is one of the key activation steps regulating the ras protein. This report describes the development of potent, non-nucleotide, small organic inhibitors of the ras nucleotide exchange process. These inhibitors bind to the ras protein in a previously unidentified binding pocket, without displacing bound nucleotide. This report also describes the development and use of mass spectrometry, NMR spectroscopy and molecular modeling techniques to elucidate the structure of a drug-protein complex, and aid in designing new ras inhibitor targets.

Can the computerized physical examination differentiate normal subjects from abnormal subjects with benign mechanical low back pain?

Inconsistencies among physicians in the evaluation of benign low back conditions make standardization desirable. A computerized physical examination device was used to evaluate low back pain patients and compare their results with a normative database obtained from a selection of healthy subjects. A high-resolution motion analysis system tracked the movement of skin markers placed on the midline and pelvis. Surface electromyography electrodes placed above L(5) collected data from multifidus. From the kinematics of skin markers during flexion extension with lifts up to 32 kg, and lateral bending with lifts up to 4.6 kg, the following parameters were estimated: lumbosacral angle and elongation, contribution of each lumbar segment to the lordosis reduction, relative pelvic/spine motion and trunk velocity. First, the average normal value for each estimated parameter was determined using 40 normal subjects. For each subject, the difference between his parameter and the normal was processed by an expert system generating a normality index varying from zero (perfect abnormal) to one (perfect normal). To develop the expert system's rules, a preliminary group of 20 very abnormal subjects were used, such that the normality index separated them from the normals. For validation, a set of 29 WCB sprain patients and another set of 42 discogram positive were selected. Each subject was tested and his computerized normality index calculated without any clinicians' input. The computerized normality index was compared with the clinicians' evaluation which was taken to be the gold standard. The Receiver Operating Characteristic technique was used to quantify the discrepancies. Results show that the expert system can detect clinically abnormal subjects with accuracy (sensitivity 83-91% and specificity >/=90%) while providing quantitative information on workers' functional capacities.

Comparative efficacy of epidural, subarachnoid, and intracerebroventricular opioids in patients with pain due to cancer

BACKGROUND AND OBJECTIVES

Although rarely used, intracerebroventricular opioid therapy (ICV) is an option for the control of intractable pain due to cancer when systemic treatments have failed. The aim of the present study is to use available data from published trials to compare ICV with the more common epidural (EP) and subarachnoid (SA) opioid treatments in an attempt to establish the utility and safety of ICV.

METHODS

Because there are no published controlled trials comparing these routes of administration, the combined data from multiple uncontrolled trials were used, with differences between the treatments analyzed statistically. Trials assessing ICV (13 trials, 268 patients). EPI (29 trials, 909 patients) and SA (21 trials, 410 patients) in cancer patients were identified; data on analgesic efficacy, common pharmacologic side effects, and complications were then extracted and the accumulated incidence data analyzed.

RESULTS

The findings (weighted means) indicated ICV to be at least as effective against pain as other neuraxial treatments, with 75% of ICV-treated patients obtaining excellent pain relief as compared with 72% of EPI- and 58% of SA-treated patients (not significant). The failure rate of both spinal treatments tended to be greater than that of ICV and was significantly higher in the case of EPI (P = .045). In general, persistent side effects appeared to be more of a problem with the spinal treatments, while transient symptoms occur more often with ICV. Persistent nausea, urinary retention, and pruritus all were more frequent with the two spinal treatments than with ICV, but transient nausea and respiratory depression occurred more often with ICV. Sedation and confusion appeared to occur more often with ICV than with spinal therapy, while constipation and headache were rarely encountered with ICV. There were no real differences in infectious complication rates among the three treatments (except for a lower rate of infection when an implanted pump was used), but technical problems such as catheter blockage, misplacement, or leakage tended to occur less often with ICV.

CONCLUSIONS

Intracerebroventricular therapy appears to be at least as effective against pain as other neuraxial treatments. The ICV technique is the only fixed system that is associated with fewer technical problems than the use of simple percutaneous epidural catheters (difference 9%, standard error of the difference 3.4). The present state of evidence indicates that ICV is a successful treatment for patients with intractable cancer pain and compares well with spinal opioid treatments in terms of efficacy, side effects, and complications.

Tolerance to subchronic, high-dose ingestion of erythritol in human volunteers

Erythritol is a sugar alcohol (polyol) which is absorbed from the small intestine in substantial amounts, not metabolized in the human body, and therefore excreted in the urine. Erythritol holds promise as a low-calorie sugar substitute. Human tolerance to repeated oral doses of erythritol was examined in a double-blind, two-way crossover study in 12 healthy, male volunteers. The participants consumed erythritol and, for comparison, sucrose for a duration of 7 days each. The daily dose of the test compounds ingested was 0.3 g/kg on Day 1, 0.6 g/kg on Day 2, and 1.0 g/kg on subsequent days. The daily dose was consumed under supervision in five portions, i.e., with the three main meals, a midmorning snack, and during the afternoon. The test compounds were incorporated into yoghurt, cookies, soft drinks, and chocolate. On each treatment day, body weight and blood pressure were measured and the participants were interviewed about side effects and their perception of stool and urine production. During the last 96 hr of each treatment period, urine was collected at 3-hr intervals during the day and for a 9-hr interval overnight for analysis of erythritol and different urinary parameters. On Days 3 to 7 of each treatment period, the participants were institutionalized. Body weights and blood pressure remained stable during the entire study. Signs of gastrointestinal intolerance were not seen and stool frequency and appearance were not different between the two treatments. The intake of liquids, which were provided ad libitum, was generally rather high (32.8 g/kg body wt/day on average) but not different between erythritol and sucrose consumption. Urine output also was high during both treatment periods. About 78% of ingested erythritol was excreted in the urine which led to a higher urinary osmolality but did not influence the 24-hr output of creatinine, citrate, urea, or electrolytes (Na+, K+, Cl-, Pi). The excretion of calcium was slightly higher during the erythritol test period but in absolute terms this increase was small. The urinary excretions of albumin, beta 2-microglobulin, and N-acetyl-glucosaminidase were slightly elevated during the erythritol test period but they were still well within the physiological range. None of the observed urinary changes became more pronounced with increasing duration of the erythritol treatment. In conclusion, the results of the present study demonstrate that the repeated ingestion of erythritol at daily doses of 1 g/kg body wt was well tolerated by humans.

Excessive mortality in market-age turkeys associated with cellulitis

Between July, 1993, and October, 1994, seven cases were examined that consisted of increased mortality in commercial turkeys due to cellulitis. The condition started at 13-16 wk of age in toms and persisted until the birds were marketed. The mortality rate was 1-2% per week. Lesions began on the ventrum of the tail and consisted of swelling and the formation of vesiclelike structures. Most of the affected birds also had an accumulation of gelatinous fluid in the subcutis of the tail and breast areas. The underlying musculature was often darkened or petechiated. Clostridium perfringens type A was isolated from two of the cases. Lesions similar to those found in the field were reproduced experimentally in turkeys injected with the subcutaneous fluid obtained from birds in field cases.

Equivalent outcomes during postoperative patient-controlled intravenous analgesia with lidocaine plus morphine versus morphine alone

To evaluate a possible opioid-sparing effect of intravenous lidocaine we conducted a randomized, double-blind clinical trial. Patients undergoing intraabdominal surgery under general anesthesia were treated with patient-controlled analgesia (PCA) in three groups: Group 1 (n = 100; morphine 1 mg/mL), Group 2 (n = 44; morphine 1 mg/mL plus lidocaine 10 mg/mL), and Group 3 (n = 51; morphine 1 mg/mL plus lidocaine 20 mg/mL). Pain was evaluated using a 0-10 visual analog scale in the postanesthesia care unit (PACU) during deep inhalation at 15 and 30 min, and at 1, 2, and 4 h after arrival in the PACU, and continued after PACU discharge every 4 h for 36 h. Patients whose pain was more than 4/10 in the PACU received 2.5 mliters of the respective solutions every 7 min until pain was less than 4/10; then PCA was started. The number of bolus and cumulative drug doses during the study were recorded. Along with pain intensity, we assessed vital signs and side effects. Time to acceptance of oral liquids was also determined. Adding lidocaine 10 or 20 mg/mL to PCA morphine 1 mg/mL for acute pain treatment after abdominal surgery yielded no differences in opioid use, pain levels, or side effects.