[Acute pain management in proximal femoral fractures: femoral nerve block (catheter technique) vs. systemic pain therapy using a clinic internal organisation model]

BACKGROUND

The aim of this study was to compare safety and efficacy of catheter-mediated femoral nerve block analgesia with systemic pain therapy in patients with proximal femoral fractures in the pre-operative and post-operative setting using a protocol for coordinating pain management.

METHODS

In a prospective randomised trial of patients attending the emergency department, 100 individuals were selected with a clinically diagnosed proximal femoral fracture. Patients were divided into two equal groups A and B. Group A (n=50) received a catheter-mediated femoral nerve block with 1% prilocaine (40 ml) and post-operatively 0.2% ropivacaine (30 ml) 6 hourly. Group B (n=50) initially received intravenous metamizol (1 g) and a fixed combination of oral tilidine (100 mg) + naloxone (8 mg). Patients aged 90 years or more received a reduced dose (tilidine 75 mg + naloxone 6 mg). In the post-operative period regular oral ibuprofen (400 mg, 8 hourly) in addition to oral tilidine (50 mg) + naloxone (4 mg) was given as required for break through pain. Pain intensity was measured using a verbal rating scale (VRS) from 1 to 5: pain free (=1), mild pain (=2), moderate pain (=3), severe pain (=4), excruciating pain (=5). Pain scores were recorded at rest (R), during passive anteflection (30 degrees) of the hip (PA) on arrival and at 15 and 30 min after initial administration of analgesia. Thereafter, recordings were made 4 times a day up to the third post-operative day.

RESULTS

Pain scores were comparable for both groups on admission (VRS in R 2.50 vs. 2.46; VRS during PA 4.30 vs. 4.34). Significant pain relief was achieved in both groups following initial administration of analgesia, but the total pain scores in group A were significantly lower than in group B (VRS in R 1.22 vs. 1.58, p<0.01 and VRS during PA 2.66 vs. 3.26; p<0.001). No difference was noted between the two groups during the first 3 post-operative days. No severe complications occurred as a result of analgesia, however, the catheter was dislodged in 20% of patients in group A resulting in the need for systemically administered analgesia.

CONCLUSION

All patients presenting with proximal femoral fractures should receive adequate analgesia within the emergency department even prior to radiographic imaging. Femoral nerve block should be considered as the method of choice. The insertion of a femoral nerve block catheter has the dual advantage of early analgesia permitting repeated clinical examination in addition to continued post-operative pain management. The cumbersome logistics inherent in this technique within the clinical setting limits its practical application. An initial single-shot regional nerve block followed by a systemic post-operative analgesia protocol was considered an appropriate alternative. The execution of safe, consistent and appropriate regional nerve block anaesthesia is reliant on formal guidelines and protocols as agreed by the multidisciplinary teams involved with patient-directed pain management and good clinical practice.

[Postoperative pain therapy with tilidin and tilidin retard as an oral patient-controlled analgesia after uncomplicated myocardial revascularization]

OBJECTIVE

The purpose of this study was to evaluate whether or not the combination of tilidin and tilidin retard as oral patient-controlled analgesia provide a suitable pain management in patients after uncomplicated myocardial revascularization.

METHODS

We conducted a randomised phase IV study to evaluate the effectiveness of postoperative analgesia with tilidin and tilidin retard. Patients with a baseline tilidin retard and tilidin liquid demand medication (group B, 42 patients) were compared with a base line paracetamol and tramadol-HCl liquid demand medication (group A, 44 patients). All patients received the first dose of study medication at the second postoperative day after evaluation of the individual pain score using NRS (numeric rating scale).

RESULTS

Pain relief in group B was significantly better only at the second postoperative day (NRS 1,8 compared to 3,3 in group A), associated with tolerable side effects and comfortable handling.

CONCLUSION

The combination of sustained release with immediate release drugs as a patient controlled analgesia provides suitable and comfortable analgesia after myocardial bypass surgery.

Adverse effects of opioid analgesic treatment are correlated with a significant elevation in plasma epinephrine in healthy humans

OBJECTIVE

The purpose of this study was to elucidate the relationship of plasma catecholamine concentrations with experienced pain intensity and analgesic effects in the setting of an experimental pain study with human volunteers.

METHODS

Plasma norepinephrine and epinephrine concentrations of 12 healthy human volunteers were analysed before and during painful electrical tooth-pulp stimulation under medication using the highly potent opioid analgesic tilidine in a fixed tilidine/naloxone combination and with the non-steroidal anti-inflammatory agent bromfenac. Catecholamine levels were compared with pharmacodynamic effects and reported adverse effects.

RESULTS

Catecholamine levels revealed a statistically significant increase in plasma epinephrine concentrations (but not norepinephrine concentrations) 60-90 min after administration of tilidine/naloxone. This was correlated with the onset of adverse effects involving vertigo episodes in all reported cases. In contrast, there was no obvious correspondence of epinephrine or norepinephrine plasma concentrations to the experience of pain and analgesia. For comparison, under medication with the non-opioid analgesic bromfenac, only one mild adverse effects were noted, and no changes in plasma epinephrine or norepinephrine could be determined during the experimental sessions.

CONCLUSIONS

It is proposed that elevated plasma epinephrine concentrations are a newly determined response to opioid-induced vertigo; this has possible clinical implications.

Comparison of tilidine/naloxone, tramadol and bromfenac in experimental pain: a double-blind randomized crossover study in healthy human volunteers

AIM

The analgesic efficacy and safety of single oral doses of two centrally acting compounds, the combination of 50 mg tilidine and 4 mg naloxone (Valoron N) and 50 mg tramadol (Tramal), were compared to 25, 50 and 75 mg of the non-steroidal antiinflammatory bromfenac in experimental pain.

SUBJECTS AND METHODS

It was a placebo-controlled double-blind 6-way crossover study design with 12 human volunteers. Acute pain was generated by electrical tooth pulp stimulation. Treatment effects were determined by recording somatosensory-evoked potentials and by subjective pain rating.

RESULTS

The tilidine/naloxone combination clearly was the most potent medication in this study, followed by bromfenac 75 mg, which produced an early pain relief. Tramadol produced poor analgesia, as did bromfenac 25 and 50 mg. There was no dose-response relationship for bromfenac. Control of plasma levels revealed pronounced interindividual differences in peak plasma concentrations for bromfenac, but not for tramadol. Tilidine/naloxone exerted adverse effects in 9, tramadol in 3 volunteers. Under medication with 25 and 50 mg bromfenac, respectively, only one subject reported adverse effects. No adverse effects were experienced with 75 mg bromfenac or placebo.

CONCLUSION

The results support previous conclusions about the analgesic efficacy of tilidine/naloxone and tramadol in experimental pain. Moreover, the findings suggest that 75 mg bromfenac might be suitable for fast but short relief of pain of non-inflammatory genesis.

Tilidine does not affect human sphincter of Oddi motility--a randomized, controlled study

AIM

To investigate the effects of intravenous pentazocine and tilidine on sphincter of Oddi motility.

METHODS

Twenty patients with suspected sphincter of Oddi dysfunction were enrolled in a prospective, double-blind study. Sphincter of Oddi motility was assessed by means of endoscopic manometry after injection of 0.9% saline, as well as after randomized dosing with either 30 mg pentazocine i.v. (n = 10) or 50 mg tilidine i.v. (n = 10).

RESULTS

Pentazocine significantly increased the sphincter of Oddi baseline pressure from 32 +/- 21 mmHg (saline) to 41 +/- 19 mmHg (P = 0.002), whereas tilidine did not alter the sphincter baseline pressure (34 +/- 15 mmHg saline vs. 36 +/- 16 mmHg tilidine, P = 0.16). Furthermore, pentazocine increased the phasic sphincter contraction amplitude (108 +/- 16 mmHg saline vs. 121 +/- 18 mmHg pentazocine, P = 0.004), but tilidine was without any effect (125 +/- 24 mmHg saline vs. 125 +/- 21 mmHg tilidine, P = 0.93). The phasic sphincter of Oddi contraction frequency and duration were not influenced either by pentazocine or by tilidine.

CONCLUSION

In contrast to 30 mg of pentazocine, 50 mg of tilidine does not affect sphincter of Oddi motility. Therefore, tilidine can be used during endoscopic manometry and for analgesia in pancreatobiliary disease.

[Changes in the pattern of opioid analgesic consumption in Spain]

BACKGROUND

Data from different sources have proved an infrautilization of opioid analgesics in Spain. A descriptive study has been conducted in order to know the utilization of these drugs and changes in the pattern of use in the last few years.

MATERIAL AND METHOD

To know the consume of narcotic analgesic drugs, N02A group of the Anatomic Therapeutic Classification, a search was developed in the ECOM database from the Spanish Ministry of Health. This database contains information of drug preparations prescribed throughout the National Health Care System.

RESULTS

The consumption of opioid analgesics in Spain has been multiplied by 5.2 during this period. It has increased from 94.7 defined daily dose per 1,000,000 inhabitants in 1985 to 489.4 in 1994. The most consumed drug in 1994 was dihydrocodeine, followed by tramadol. The number of defined daily dose per inhabitant and day of parenteral administration have decreased during the last years.

CONCLUSIONS

Availability of new analgesic opioid drugs with better pharmacokinetic profiles has contributed to an increase of their consume in Spain.

[Comparison of the action of 2 effective analgesics. Experimental study: tramadol versus tilidine/naloxone]

In the present study involving healthy test subjects, tilidin/naloxone (Valoron N; VAL) proved to have an analgesic effect roughly twice as pronounced as that of tramadol (TRA). Moreover, the analgesic effect of VAL showed a significantly more rapid onset than did that of TRA. This finding reflects the difference in rate of action of the active substances. In accordance with these findings, VAL is thus the most powerful analgesic presently available on the German market on simple prescription.

[Initial experience with preorally administered dipotassium clorazepate and tilidine-naloxone in extracorporeal shockwave lithotripsy]

After 70 treatments with extracorporeal shock wave lithotripsy (ESWL), using a combination of dipotassiumclorazepate p.o. 12 h before treatment and tilidin-naloxon 45 min before ESWL, 56 patients reported to be painfree or only minor, well-tolerable pain. Informed consent was obtained in all patients for this pilot study, leaving the possibility of further pain medication. 7 patients asked for an additional analgesic (fentanyl) and another 7 patients required a sedative (midazolam). No further anesthesiologic procedures were necessary. Nausea was observed in one patient as a possible side-effect of tilidin. To confirm these preliminary results, a prospective randomized study is currently conducted.

Modern techniques to measure pain in healthy man

This paper describes a series of experimental prerequisites in assessments to measure the efficacy of analgesic drugs in healthy man. Of course, there is no doubt that an analgesic has to prove its validity exactly where it ought to help; i.e. in the patient suffering from pain. But to objectify the mode of action, or to measure dose-response functions, to evaluate the optimal therapeutic dosage, or to compare the relative efficacy of the drug tested with known substances--all these investigations can best be performed in a sample of healthy, informed, intelligent and cooperative volunteers, as homogenous as possible. Various kinds of stimuli used in the experimental pain laboratory will be compared with respect to their usefulness in algesimetry; for example the CO2 laser stimulus and the intracutaneous electrical shock. New examples in the analysis of cerebral potentials evoked by painful stimuli will be presented, such as the principal component analysis, the maximum entropy method, and procedures of cerebral potential mappings. It will be shown that frequency transformation of stimulus-induced changes in the electroencephalogram can result in a powerful tool to verify effects even of the so-called weak analgesics, such as acetyl salicylic acid (Aspirin).

[Comparison of diflunisal and tilidine in tumor pain]

In an open study in patients with tumour-induced pain the analgetic effects of the prostaglandin-inhibiting compound diflunisal and the centrally-acting analgetic tilidine N were compared. A dosage of 1 g diflunisal was found to be equivalent to 50 drops of tilidine N and to be subjectively well-tolerated. In the pain-relieving therapy of tumour patients diflunisal appears to offer a genuine alternative to centrally-acting analgetics.

Control of cancer pain with analgesics acting in the central nervous system

Systemic administration of opioids is one of the traditional, but by no means optimized therapeutic procedures in cancer pain. Besides the underlying pathophysiology, appropriate treatment has to take into account the psychodynamics and behavior of the patient as well as his life expectancy. In view of this, therapy with centrally acting analgesics can be considered after administration of analgesics with peripheral action first and then of psychoactive agents. Nefopam is a centrally (but not spinally) acting analgesic with a novel activity profile. Its advantages and disadvantages in the treatment of carcinoma pain are outlined. The opiate agonist-antagonist principle has the advantage of a lower dependence and tolerance potential. In addition, the preparations pentazocine, tilidine plus naloxone, and buprenorphine deviate from the morphine derivatives in various constituent effects. Their actions and side effects are outlined. The optimization of control of cancer pain is not possible without taking into account the time dimension. In 50 pain patients with advanced cancer, the following main errors were observed in previous treatment of pain syndromes: (1) too early parenteral administration in the course of the disease; (2) underdosage; (3) application intervals that were too long; and (4) use of analgesics as needed by the patient or on request and not according to a time schedule.

Double blind study with nefopam, tilidine and placebo, for postoperative pain suppression

A double-blind study involving 101 patients was done to assess the efficacy of parenteral nefopam (0.66 mg/kg) for postoperative pain suppression, in comparison to tilidine (1.67 mg/kg) or placebo. The difference in painfree duration for both active drugs compared to placebo is significant, but no significant difference was present between them; although tilidine was a little longer acting. At no moment a significant difference was present in the pain score of the patients receiving one of both active drugs. Only minor changes of blood pressure, heart rate and respiratory frequency were seen and marked side effects were not present in any of the patients.

[Tilidine as an analgesic in combination anesthesia]

In 2446 "insufflation anesthesias" the usefulness of Tilidine as an analgesic has been established. The preferred combinations were with Methohexital, Dehydrobenzperidol, Nitrous oxide, Succinyl and Diallyl-Nortoxiferine.

A clinical comparison of tilidine hydrochloride and pentazocine, given orally for the treatment of postoperative pain

A controlled, double-blind study involving 250 women was carried out ot assess the efficacy of oral tilidine 25, 50 and 100 mg in treating postepisiotomy pain, and to offer a comparison with oral pentazocine 50 mg. All the analgesics produced significant pain relief. At peak effect tilidine 50 mg produced very similar results to pentazocine 50 mg with tilidine 25 mg producing less, and tilidine 100 mg more pain relief. These results were not, however, statistically significant. In these postdelivery ambulant patients pentazocine 50 mg and tilidine 100 mg produced at 25% incidence of side-effects, mainly dizziness and drowsiness, but tilidine 25 mg produced significant analgesia with virtually no side-effects.

[Double-blind study on the analgesic efficacy of tilidine (valoron) and pethidine (dolantin) in gastro-intestinal endoscopies and liver biopsies (author's transl)]

In a double-blind trial involving 99 patients, equi-analgesic doses of tilidine and pethidine (100 mg of each i.m.) were compared as to their effectiveness in laparoscopies, gastroscopies, esophagoscopies and liver needle biopsies. The two substances produced equally analgesic effects both during and after the various procedures, with the exception of the liver biopsies, in which tilidine was shown to be significantly more effective than pethidine. Whereas no sedation was noted in connection with tilidine medication, pethidine produced a marked, undesirable sleepiness in 12% of the cases observed. Due to the high analgesic efficacy and tolerance of tilidine found in both this and numerous other clinical trials and to its particular advantages over pethidine and other opiates (no respiratory depression, no effect on intestinal motility) tilidine can be recommended for premedication in gastrointestinal endoscopies and liver needle biopsies. Tilidine (Valoron) is not subject to the restrictions imposed by the West German narcotics laws.

A comparison of tilidine hydrochloride and morphine in the treatment of postoperative pain

Intramuscular injections of 10 mg morphine or 100 mg tilidine hydrochloride were administered in a double-blind fashion and in random order to 40 patients after minor surgical operations. The therapeutic effect of each analgesic was assessed by comparing the severity of pain immediately postoperatively with that 1, 2, 3 and 4 hours after injection of the relevant analgesic. Tilidine and morphine relieved pain to a similar degree. Within the limits of the protocol followed, morphine appeared superior to tilidine in some tests. No major side-effects occurred.

The interaction of tilidine and pethidine in postoperative pain

The mode of interaction between the new, non-narcotic analgesic tilidine and pethidine was studied in the treatment of postoperative pain. The potency ratio 3:1 (pethidine:tilidine) found previously was used in the comparison. Thus 0.25 mg/kg of pethidine with 0.75 mg/kg of tilidine and 0.5 mg/kg of pethidine with 1.5 mg/kg of tilidine were compared with 0.5 mg/kg and with 1.0 mg/kg of pethidine. These drug combinations proved to be equipotent with the pethidine dosages used. Consequently the mode of interaction seemed to be additive synergism. The onset of action was slightly faster with pethidine, but the duration of action was longer with pethidine-tilidine combinations. Respiratory depression and sedation were less evident after pethidine-tilidine combinations than after equianalgesic doses of pethidine. Circulatory effects were similar in all groups. No statistical difference in other side effects could be demonstrated between the groups.