A two-year experience of an acute pain service in Singapore

The first anaesthesia-based acute pain service in Singapore is described. The benefits, risks and resource implications of such a service during its first two years are reviewed. One thousand two hundred and sixty-eight (1,268) post-operative patients were treated with either patient-controlled analgesia (310 patients) or epidural opioid analgesia (958 patients). Retrospective analysis of the data revealed good patient satisfaction with a low incidence of potentially life threatening side-effects: more than 79% of patients reported satisfaction with pain control while only 0.2% of patients receiving epidural opioid analgesia experienced clinically significant respiratory depression. There were no reports of respiratory depression in the patient-controlled analgesia group. The authors conclude that the provision of an acute pain service in the local context was safe and resulted in excellent post-operative patient satisfaction.     

Discovery of a new cyclooxygenase-2 lead compound through 3-D database searching and combinatorial chemistry

Prolonged nerve conduction blockade has been proposed to result from the summed effects of charged and neutral local anaesthetics. Thirty-seven patients were randomly allocated to receive intravenous patient-controlled analgesia alone or combined with intercostal blockade (T7-T11) with a mixture of 0.45% bupivacaine and 0.6% phenol for post-cholecystectomy analgesia. Adequacy of pain relief was measured by patient scores on a 10-cm visual analogue scale and by dose-demand ratio, amounts of loading dose and total consumption of morphine and also the duration of patient-controlled analgesia in each group. No differences were found between groups in post-operative scores, dose-demand ratios and loading doses of morphine. However, in the combined treatment group, a significantly lower total consumption of morphine (P < 0.05), associated with a shorter duration of patient-controlled analgesia (P < 0.02) and a decreased mean number of unsuccessful demands (P < 0.001) were recorded. Intercostal blockade with bupivacaine-phenol supplements intravenous patient-controlled analgesia for post-cholecystectomy pain relief.     

Natural variation within the principal arginine-specific protease gene, prpR1, of Porphyromonas gingivalis

Patients who were treated for fractures of the limbs were assigned to 1 of 2 groups for the management of postoperative pain. In Group 1 (postoperative patient-controlled analgesia group), 46 patients were given postoperative continuous epidural anaesthesia in combination with narcotic analgesics and this was regulated by the patient using a device. The 46 patients in Group 2 (control group) received suppositories or intramuscular injections of narcotic analgesics on their request. Patients in Group 1 needed suppositories and intramuscular injection of narcotic analgesics less often than those in Group 2, and had more satisfactory pain relief according to the visual analogue scale for pain assessment made on the first, second and third postoperative day. The time spent by nurses for pain management in Group 1 was less than that in Group 2. It appears that this patient-controlled method, combined with postoperative continuous epidural anaesthesia, is a safe, effective and efficient method for the management of postoperative pain.     

Drug-induced gingival hyperplasia and its management--a literature review

The purpose of our study was to find out whether patient-controlled epidural administration (PCEA) of a mixture containing a low-dose local anaesthetic, opioid and alpha 2-agonist provides as good or better postoperative analgesia as continuous epidural administration of the same analgetic solution. METHODS: 30 patients (ASA I-III), scheduled for major abdominal surgery, were randomly divided into 2 groups. 90 minutes after induction of general anaesthesia all patients received a continuous epidural infusion of 5 ml/h of the analgetic solution (50 micrograms sufentanil + 150 micrograms clonidine in 50 ml 0.125% bupivacaine) until the end of surgery. Immediately postoperatively the patients of group A received a continuous infusion of the study solution (5-8 ml/h), the patients of group B received a baseline continuous epidural infusion (3 ml/h), additionally they could self-administer 5 ml boli via a PCEA device. Measurements included the total dose of infused drug solution, pain at rest and on exercise by a visual analogue scale, cardiorespiratory data and side effects within the first 24 hours postoperatively. A standardised interview on analgesia and side effects was held 2 days after surgery. RESULTS: The PCEA group demanded less epidural analgesics (gr. B: 112 +/- 33 ml vs. gr. A: 135 +/- 20 ml) p < 0.01). Both continuous epidural infusion and patient-controlled administration provided very good analgesia at rest (gr. A: VAS 0.4 +/- 0.4 and gr. B: VAS 0.4 +/- 0.5) (n.s.). On exercise continuous epidural infusion of analgesics resulted in significantly lower pain scores (gr. A: 1.9 +/- 1.1) than patient-controlled application (gr. B: 3.4 +/- 1.1) (p < 0.01). We did not notice severe side effects such as respiratory depression or drop of heart rate or blood pressure. CONCLUSION: In patients at rest both continuous and patient-controlled epidural administration of analgesics provides excellent analgesia after major abdominal surgery. Contrariwise, patients on exercise who could use a PCA-device experienced more pain compared to those with a continuous epidural infusion technique. On the other hand the patients of the PCA-group consumed less epidural analgesics. We did not notice any severe side effects such as respiratory depression or cardiovascular instability during the study.     

Efficacy and costs of patient-controlled analgesia versus regularly administered intramuscular opioid therapy

BACKGROUND: Many studies have shown the efficacy of patient-controlled analgesia (PCA). However, it is not clear whether PCA has clinical or economic benefits in addition to efficient analgesia. The current study was designed to evaluate these issues by comparing PCA with regularly administered intramuscular injections of opioids after hysterectomy. METHODS: This prospective study included 126 patients who underwent abdominal hysterectomy and were randomly assigned to receive PCA or regularly timed intramuscular injections of morphine during a period of 48 h. Doses were adjusted to provide satisfactory analgesia in both treatment groups. Pain at rest and with movement, functional recovery, drug side effects, and patient satisfaction were measured using rating scales and questionnaires. The costs of PCA and intramuscular therapy were calculated based on personnel time and drug and material requirements. RESULTS: Comparable analgesia was observed with the two treatment methods, with no significant differences in the incidence of side effects or patient satisfaction. The medication dosage had to be adjusted significantly more frequently in the intramuscular group than in the PCA patients. The PCA did not favor a faster recuperation time compared with intramuscular therapy in terms of times to ambulation, resumption of liquid and solid diet, passage of bowel gas, or hospital discharge. The results of the economic evaluation, which used a cost-minimization model and sensitivity analyses, showed that PCA was more costly than regular intramuscular injections despite the fact that no costs for the pump were included in the analyses. Cost differences in nursing time favoring PCA were offset by drug and material costs associated with this type of treatment. CONCLUSIONS: Compared with regularly scheduled intramuscular dosing, PCA is more costly and does not have clinical advantages for pain management after hysterectomy. Because of the comparable outcomes, the general use of PCA in similar patients should be questioned.     

Patient-controlled intranasal analgesia: a method for noninvasive postoperative pain management

Recently, a new device for patient-controlled intranasal analgesia (PCINA) was described, and a pilot study demonstrated promising results with respect to efficacy and patient satisfaction. The present study compares PCINA with intravenous (IV) patient-controlled analgesia (PCA). Fifty orthopedic patients were prospectively studied over an 8-h period on the first day after surgery. The patients were randomly allocated to PCINA group (n = 25) or to an IV PCA group (n = 25). Pain intensity was evaluated at 30-min intervals using a 101-point numerical rating scale. With respect to initial pain intensity, there was no significant intergroup difference. At the 30- to 480-min measurement points pain intensity in the PCINA group (P < 0.0001) and the IV PCA group (P < 0.0001) was significantly less as compared to the initial value. There was no significant intergroup difference in pain intensity. No patient had problems using the PCINA device. The present study demonstrates, that PCINA provides relief of postoperative pain as effectively as IV PCA.     

Post-operative analgesia for craniotomy patients: current attitudes among neuroanaesthetists

As part of an evaluation of post-operative analgesia for craniotomy patients, a postal questionnaire was sent to 183 consultant members of the Neuroanaesthesia Society of Great Britain and Ireland, inquiring about their current practices for post-operative neurosurgical analgesia. Replies were received from 110 neuroanaesthetists in 37 different neurosurgical centres. Intramuscular codeine phosphate or dihydrocodeine was the mainstay of post-operative analgesia for 97% of neuroanaesthetists despite the fact that over half of them thought that analgesia was inadequate. Only four neuroanaesthetists would ever consider using opioids post-operatively because of fears about respiratory depression and sedation, yet all except one used opioids per-operatively. Post-operative analgesia for craniotomy patients is perceived as inadequate by most neuroanaesthetists, yet traditional prejudice against opioid use prevents this being remedied. We suggest that patient-controlled analgesia with morphine could be a safe alternative to codeine phosphate.     

Determination of an effective dose of intrathecal morphine for pain relief after cesarean delivery

Very small doses of intrathecal (i.t.) morphine (25-200 microg) have been used in an effort to provide effective postoperative pain relief while minimizing side effects after cesarean delivery. We performed a double-blinded study in 40 patients presenting for elective cesarean delivery in which i.t. morphine was administered along with oral hydrocodone/acetaminophen and other medications commonly administered after cesarean delivery. We administered i.t. morphine by up-down sequential allocation of doses. For the purposes of this study, adequate postoperative analgesia was defined as comfort not requiring i.v. morphine for 12 h after spinal anesthesia with bupivacaine, fentanyl, and morphine. In addition, a time and cost comparison was performed for study patients receiving intrathecal morphine compared with a historical group of patients receiving patient-controlled analgesia with i.v. morphine. We were unable to determine with meaningful precision a dose of i.t. morphine to provide analgesia in this context. However, very small doses of i.t. morphine combined with oral hydrocodone/acetaminophen and other medications commonly prescribed after cesarean delivery provided postoperative pain relief with no more time commitment than patient-controlled analgesia (148 +/- 61 vs 150 +/- 57 min) and with significantly less acquisition cost ($15.13 +/- $4.40 vs $34.64 +/- $15.55). Implications: When used along with oral analgesics, very small doses of spinal morphine provide adequate pain relief after cesarean delivery. Spinal anesthetics, oral analgesics, and other medications commonly prescribed to treat side effects after cesarean delivery contribute significantly to this analgesia. When small doses of spinal morphine are used in this setting, they provide adequate analgesia and patient satisfaction that is time- and cost-effective.     

A prospective randomized comparison of epidural infusion of fentanyl and intravenous administration of morphine by patient-controlled analgesia after radical retropubic prostatectomy

In a prospective, randomized study, continuous infusion of epidural fentanyl citrate (group E) was compared with patient-controlled intravenously administered morphine sulfate (group P) for analgesia in 66 men after radical retropubic prostatectomy. Although both methods provided satisfactory analgesia, the mean comfort level scores were lower (that is, greater comfort) in group E than in group P at all observation times. The difference in mean resting comfort level scores between groups E and P was statistically significant (P < or = 0.05) at 9 of the 11 observation times. In addition, significant differences in comfort level scores were noted at 8 of the 11 observation times during deep breathing, 5 of 11 during coughing, and 3 of 9 during ambulation. Maximal and minimal comfort level scores recorded by each patient during the course of the study were significantly lower (that is, less pain) in group E than in group P for all four categories of activity. The percentage of patients who reported no pain was significantly higher in group E than in group P at 9 of 11 observation times during resting and 5 of 11 observation times during deep breathing. No significant differences were noted in side effect profiles or duration of hospital stay. In summary, when two effective methods of analgesia used after radical retropubic prostatectomy were compared prospectively, patients who received epidural infusion of fentanyl were more comfortable than those with patient-controlled intravenous administration of morphine, as evidenced by lower mean, maximal, and minimal comfort level scores and a greater proportion of patients with complete relief of pain.     

Relative aversiveness of signaled vs. unsignaled avoidable and escapable shock situations in humans.

Conducted 2 experiments dealing with signaled and unsignaled shock, using a total of 18 male college students. In Exp I 6 Ss avoided shock, and in Exp II 12 Ss escaped shock by pressing one button under an unsignaled shock condition. By pressing on a separate button, Ss could change to signaled avoidance (Exp I) or signaled escape (Exp II). All Ss changed from the unsignaled to signaled condition whether shock was avoidable or escapable. 6 Ss were also given a chance to change from signaled to unsignaled escapable shock. Changeover responding remained at or near operant levels for these Ss. Comparing results of this study with studies using the rat revealed much similarity but some differences. Differences depended upon whether an escapable or avoidable procedure was used. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The sedative and analgesic sparing effect of music

BACKGROUND: To determine whether music influences intraoperative sedative and analgesic requirements, two randomized controlled trials were performed. METHODS: In phase 1, 35 adults undergoing urologic procedures with spinal anesthesia and patient-controlled intravenous propofol sedation were randomly assigned to hear favorable intraoperative music via headset or to have no music. In phase 2, 43 adults undergoing lithotripsy treatment of renal or ureteral calculi and receiving patient-controlled intravenous opioid analgesia were randomly assigned to either a music or no-music group. The effect of music on sedatives and analgesics requirements, recovery room duration, and adverse outcomes was assessed. RESULTS: In phase 1, patients in the music group required significantly less propofol for sedation than patients in the control group (0 [0-150] mg vs. 90 [0-240] mg, median[range]; P < 0.001). These findings persisted after adjusting for duration of surgery (0.3+/-0.1 mg/min vs. 1.6+/-0.4 mg/min; P < 0.001). Similarly, in phase 2, patients who listened to music had a significant reduction in alfentanil requirements (1,600 [0-4,250] microg vs. 3,900 [0-7,200] microg; P = 0.005). This persisted after adjusting for duration of surgery (52+/-9 microg/min vs. 119 +/-16 microg/min, mean +/- SD, P < 0.001). Duration of stay in the postanesthesia care unit and the rate of adverse events was similar in both groups (P = NS). CONCLUSIONS: Use of intraoperative music in awake patients decreases patient-controlled sedative and analgesic requirements. It should be noted, however, that patients in the no-music group did not use a headset during operation. Thus, the decrease in sedative and analgesic requirements could be caused by elimination of ambient operating room noise and not by the effects of music.     

The effect of the addition of adrenaline to pethidine for patient-controlled epidural analgesia after caesarean section

We have investigated the addition of adrenaline to pethidine for patient-controlled epidural analgesia after elective Caesarean section. In a randomised, double-blind study, patients received patient-controlled epidural analgesia for 24 h using pethidine 5 mg.ml-1 with adrenaline 5 micrograms.ml-1 (adrenaline group, n = 40) or pethidine 5 mg.ml-1 without adrenaline (plain group, n = 38). Visual analogue scale pain scores at rest and on coughing measured 2 h, 6 h and 24 h after surgery were similar between the two groups. There was a trend towards lower mean total consumption of pethidine in the adrenaline group (231.5 mg; SD 140.5 mg) compared with the plain group (289.5 mg; SD 139.5 mg; p = 0.071). Patients in the adrenaline group had higher visual analogue scale scores for nausea at 2 h and 24 h and higher scores for pruritus at 2 h compared with the plain group. Addition of adrenaline to pethidine for patient-controlled epidural analgesia does not appear to have significant clinical advantages.     

Thoracic versus lumbar epidural anesthesia's effect on pain control and ileus resolution after restorative proctocolectomy

BACKGROUND: Epidural anesthesia as a perioperative adjunct has been shown to provide superior pain control and has been implicated in more rapid ileus resolution after major abdominal surgery, possibly through a sympatholytic mechanism. Studies suggest that the vertebral level of epidural administration influences these parameters. METHODS: One hundred seventy-nine patients (120 male, 59 female; average age, 36 years) underwent restorative proctocolectomy for ulcerative colitis or familial polyposis between 1989 and 1995. Patients were grouped according to type of anesthesia. Group THO (n = 53) received thoracic (T6 to T10) epidurals. Group LUM (n = 51) received lumbar (L2 to L4) epidurals, and group PCA (n = 75) received patient-controlled intravenous narcotic analgesia. Patients were compared for complications, perioperative risk factors, postoperative pain, and ileus resolution. RESULTS: Epidural narcotics, alone or combined with local anesthetics, were administered for an average of 2 (LUM) to 4 (THO) days without significant complications. Infrequent problems related to the epidural catheters included self-limited headaches or back pain (four) and site infections (two). Epidural failure, as measured by conversion to PCA for inadequate pain control, was not significantly greater for LUM (25%) than THO (23%). Average pain scores, rated daily on a visual analog scale, were significantly higher (indicating more pain) for PCA patients (4.2) during postoperative days 1 through 5 than for LUM (3.5) (p < 0.05) and for THO (2.4) (p < 0.05). Ileus resolution, as determined by stool output and return of bowel sounds, was significantly faster in THO than in LUM or PCA (p < 0.05). Resolution of ileus was not significantly different between PCA and LUM (p > 0.05). CONCLUSIONS: Thoracic epidural analgesia has distinct advantages over both lumbar epidural or traditional patient-controlled analgesia in shortening parameters measuring postoperative ileus and in reducing surgical pain. The procedure is safe and associated with low morbidity. Thoracic epidural anesthesia is also economically justifiable and may prove to impact significantly on future postoperative management by reducing length of hospitalization. Our data and those of others are most striking in these regards for patients with thoracic catheters, indicating the importance of vertebral level in epidural drug administration.     

A medical audit and patient survey of hysterectomies performed for menstrual disorders

The aim of the study was to carry out an audit of 283 hysterectomies performed for menstrual disorders over a one year period, and to determine the satisfaction of the women concerned towards their treatment. The medical records of these patients were examined, and they were each sent a questionnaire, 69% of which were completed and returned. The most common presenting symptoms were menorrhagia and dysmenorrhoea. In 53% of cases no clinical abnormality was postulated and in 31% of cases no pathological abnormality was found. The preoperative clinical and pathological diagnoses were in agreement for 59% of patients. Over 90% of women were satisfied with the management of their case by their GP and the gynaecology outpatient clinic. The use of patient-controlled analgesia systems was associated with better post-operative pain relief than intramuscular injections. Thirteen percent of patients required blood transfusion; 21% suffered some form of postoperative complication, most of which were minor. Ninety-four percent of the women were pleased that they had undergone hysterectomy, and 76% wished that they had had the operation sooner. It was concluded that hysterectomy is perceived positively by patients and should not necessarily be considered as a last resort treatment for menstrual disorders.     

Changing the practice of pain management

Since postoperative pain is associated with morbidity and increased hospital resources, reducing pain should improve patient care. Enhanced education and individualized feedback were introduced at the study hospital to promote anesthesiologists' use of patient-controlled analgesia, nonsteroidal antiinflammatory drugs, epidural morphine, and nerve blocks. After 6-mo baseline, anesthesiologists at the study hospital attended educational seminars and received literature about pain management. Personalized feedback forms were then distributed to each anesthesiologist showing the management and rates of pain for their patients. Practice was as usual at a control hospital. Pain in the postanesthesia care unit (PACU) and for 6-h post-PACU discharge was assessed using PACU records and interviews for 3413 patients at the study hospital and 1753 at the control hospital. From the baseline to the feedback period, the absolute increase in the proportion of patients receiving at least one promoted strategy was greater at the study hospital than at the control hospital (44.9% vs 22.8% P < 0.0001). Mean pain scores with activity decreased at both hospitals; study hospital 7.6 (7.3-7.8, 99% confidence interval) to 6.2 (5.9-6.5); control hospital 7.3 (6.9-7.6) to 6.1 (5.7-6.4). Education and feedback increased the use of pain management strategies at the study hospital. The modest change in patient outcome was unlikely related to directed interventions.     

Respiratory depression associated with patient-controlled analgesia: a review of eight cases

Patient-controlled iv delivery of opioids for postoperative pain management is a popular alternative to the traditional im route of administration. However, occasional patients receiving opioids in this manner develop severe respiratory depression. The purpose of this paper is to determine the incidence of, and factors contributing to, the development of this complication. To do this, the Office of Medical Quality Improvement retrospectively searched for reports of respiratory depression in a database compiled from the charts of approximately 1600 patients who had received PCA at the University of Alberta Hospitals in 1992. Eight cases of serious respiratory depression were detected. Factors associated with the occurrence of respiratory depression included the concurrent use of a background infusion, advanced age, concomitant administration of sedative/hypnotic medications, and pre-existing sleep apnoea syndrome. No cases were attributed to operator error or equipment malfunction. In conclusion, the risk of respiratory depression with patient-controlled opioid administration is similar to that observed when opioids are delivered by the traditional im or spinal routes. The safe and effective use of patient-controlled analgesia depends upon knowledgeable medical and nursing staff, clearly defined nursing policy and procedures, and frequent patient follow-up.     

Psychosocial concerns of Nigerian women with breast and cervical cancer

Many studies have demonstrated that the management of pain after surgery was unsatisfactory. New pain management techniques have been developed in recent years (patient-controlled analgesia, epidural analgesia). To extend the number of patients who may benefit from these recent techniques and/or to obtain the best efficacy from existing methods of pain relief, re-organisation should take place on surgical wards. For example, protocols describing pain management strategies should be written. Surveys and audits should be carried out regularly to check their efficacy. Moreover, patients should be fully informed of the range of treatments available and their adverse effects. Finally, all staff involved in providing acute pain relief should undergo training.     

Results of the Bruce treadmill test in children after arterial switch operation for simple transposition of the great arteries

In a double-blind, placebo-controlled clinical trial (power of 80% to detect a 30% reduction in morphine consumption, P < 0.05) we have determined that intraoperative intravenous administration of tenoxicam 40 mg during laparoscopic cholecystectomy, when compared with placebo, was associated with a significant reduction in consumption of morphine at 6 hours and 12 hours (P < 0.05) but not at 24 hours, when assessed by patient-controlled analgesia. Furthermore there was a significantly greater requirement for "rescue" analgesia with intramuscular morphine in the placebo group during the period of the study. There was no difference between the groups in pain scores, either at rest or on movement, nor in the incidence of nausea and vomiting. No patient in either group suffered a respiratory rate less than 8/min or oversedation at any time, and there were no other adverse effects.     

Correlation between motility of testicular spermatozoa, testicular histology and the outcome of intracytoplasmic sperm injection

Many studies have demonstrated the postoperative analgesic efficacy of fentanyl delivered i.v. by patient-controlled analgesia (PCA) devices at demand doses ranging from 10 to 50 microg, but none has sought to define the optimal fentanyl PCA dose. In this randomized, double-blind, multicenter study, we compared the safety and efficacy of three administered demand-dose sizes of fentanyl (20, 40, and 60 microg) in 150 patients after major surgery. Efficacy was dose-dependent; positive response rates (i.e., a global assessment score of "very good" or "excellent" and the absence of severe opioid adverse effects) were 42%, 52%, and 68% for the 20, 40, and 60 microg demand-dose groups, respectively, and were significantly higher in the 60 microg demand-dose group. The number of doses administered and missed attempts were significantly smaller in the 40 and 60 microg demand-dose groups compared with the 20 microg demand-dose group. This suggests that the 20 microg demand dose provided inadequate pain relief. Adverse respiratory events were more frequent and mean respiratory rates were significantly slower with the 60 microg demand dose, compared with the 20 or 40 microg demand doses. These results indicate that, of these three doses, the 40 microg demand dose was optimal for fentanyl PCA management of moderate to severe pain after major surgery. IMPLICATIONS: The postoperative analgesic efficacy of fentanyl delivered i.v. by patient-controlled analgesia devices has been demonstrated for demand doses ranging from 10 to 50 microg, but the optimal fentanyl dose remains unknown. In this randomized, double-blind study, we compared three demand dose sizes of fentanyl (20, 40, and 60 microg) and found that the 40 microg demand dose was the most appropriate for fentanyl patient-controlled analgesia management of postoperative pain.     

High-Resolution Infrared Fourier-Transform Spectroscopy and Rotational Constants of the nu4 Band of BrNO2

In this study, we assessed the influence of three analgesic techniques on postoperative knee rehabilitation after total knee arthroplasty (TKA). Forty-five patients scheduled for elective TKA under general anesthesia were randomly divided into three groups. Postoperative analgesia was provided with i.v. patient-controlled analgesia (PCA) with morphine in Group A, continuous 3-in-1 block in Group B, and epidural analgesia in Group C. Immediately after surgery, the three groups started identical physical therapy regimens. Pain scores, supplemental analgesia, side effects, degree of maximal knee flexion, day of first walk, and duration of hospital stay were recorded. Patients in Groups B and C reported significantly lower pain scores than those in Group A. Supplemental analgesia was comparable in the three groups. Compared with Groups A and C, a significantly lower incidence of side effects was noted in Group B. Significantly better knee flexion (until 6 wk after surgery), faster ambulation, and shorter hospital stay were noted in Groups B and C. However, these benefits did not affect outcome at 3 mo. We conclude that, after TKA, continuous 3-in-1 block and epidural analgesia provide better pain relief and faster knee rehabilitation than i.v. PCA with morphine. Because it induces fewer side effects, continuous 3-in-1 block should be considered the technique of choice. Implications: In this study, we determined that, after total knee arthroplasty, loco-regional analgesic techniques (epidural analgesia or continuous 3-in-1 block) provide better pain relief and faster postoperative knee rehabilitation than i.v. patient-controlled analgesia with morphine. Because it causes fewer side effects than epidural analgesia, continuous 3-in-1 block is the technique of choice.