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D Fletcher

Publications and source records attributed to D Fletcher.

At least 55 records · Page 3Linked to original sources
PubMed1998

[Prevention of postoperative pain].

The pre-emptive analgesia concept suggests that pre-administration of analgesics may enhance the efficacy of these drugs. This review has selected the data from the literature according to two types of methodological criteria: Sackett's criteria, and those specific of pre-emptive analgesia studies. Infiltration, spinal and peripheral nerve blocks using local anaesthetic drugs do not seem to produce pre-emptive analgesia. The few positive results have limited clinical significance. The results concerning opioids are contradictory and the clinical significance is limited. Preoperative oral administration of non steroidal anti-inflammatory drugs (NSAIDs) offers no benefit. Intravenous pre-administration has a limited advantage, but enhances perioperative bleeding. Ketamine, an NMDA receptor antagonist, may have some pre-emptive analgesic properties according to the few studies available. In conclusion, pre-administration of analgesic drugs represents the usual strategy for the anaesthesiologist (spinal or peripheral block, infiltration, opioids). In other cases (NSAIDs, ketamine), pre-administration represents a change in usual practice. This is not justified for NSAIDs; NMDA receptor antagonists may offer an interesting research area. Data concerning pre-emptive analgesia for chronic pain syndrome such as phantom limb pain are quite limited.

Analgesia↗
PubMed1997

Postoperative analgesia with i.v. propacetamol and ketoprofen combination after disc surgery.

PURPOSE: The concept of balanced analgesia suggests that a combination of analgesic drugs may enhance analgesia and reduce side effects after surgery. This study evaluated the effect of the combination of propacetamol (Prodafalgan) and ketoprofen (Profenid) after surgery of a herniated disc of the lumbar spine. METHODS: After randomization, 60 patients received: placebo (group 1); 2 g propacetamol (group 2); 50 mg ketoproten (group 3); or a combination of 2 g propacetamol and 50 mg ketoprofen (group 4). Drugs were administered every six hours for two days after surgery. The patients used morphine with patient controlled analgesia pumps (bolus 1 mg; lock out time 10 min) and were evaluated with a visual analogue scale (VAS) at rest and movement every six hours for two days. Side effects were noted. RESULTS: The patient characteristics and surgery were identical for each of the four groups. The VAS scores throughout the study were lower in group 4 than in groups 1, 2 and 3 both at rest (P < 0.05) and on movement (P < 0.01). The cumulative dose of morphine at 48 hr was lower in group 4 than in group 1 (23.4 +/- 5 mg vs. 58.9 +/- 9 mg; P < 0.01) or group 2 (23.4 +/- 5 mg vs 43.4 +/- 6.6 mg; P < 0.05) and similar to that in group 3 (34.2 +/- 4.5 mg). The incidence of side effects was similar in all groups. CONCLUSION: The combination of propacetamol and ketoprofen reduced pain scores both at rest and on movement. The drug combination did not reduce the morphine consumption and incidence of side effects.

Acetaminophen↗
PubMed1997

Venous air embolism during orthotopic liver transplantation in a child.

PURPOSE: A first case of massive venous air embolism is reported as a complication of orthotopic liver transplantation in a 17-month-old child during the dissection phase. CLINICAL FEATURES: During the hepatic dissection phase, perforation of suprahepatic veins was responsible for an air embolism with a decrease of P(ET)CO2 (27 to 6 mmHg), hypoxaemia (SpO2 decreased from 100 to 88%), and haemodynamic instability (systolic blood pressure decreased from 85 to 50 mmHg, central venous pressure increased from 6 to 10 mmHg). Central venous aspiration of air was unsuccessful but immediate resolution occurred and neurological outcome was normal. CONCLUSION: Venous air embolism during the dissection phase of liver transplantation in children is a risk that should be considered

Carbon Dioxide↗
PubMed1997

The influence of the timing of bupivacaine infiltration on the time course of inflammation induced by two carrageenin injections seven days apart.

The mechanical allodynia and edema related to a subcutaneous carrageenin injection are increased by a conditioning carrageenin injection 7 days before (Guilbaud et al., 1992). In the present study, the possibility of preventing this by bupivacaine infiltration was tested. In the first part of the experiment, the time course of a carrageenin induced inflammation of the right hind paw was assessed in animals receiving local anesthetic injection (0.2 ml of bupivacaine 0.5% solution with epinephrine) either 5 min before (BUPI PRE group) or 60 min after (BUPI POST group) the carrageenin injection (0.2 ml of 1% solution). Control groups received saline (0.2 ml) with the same timing. In the second part of the experiment, 7 days later, a carrageenin injection was performed either in the right or the left hind paw. Mechanical allodynia and edema were evaluated by the vocalization threshold to paw pressure (VTPP) and paw circumference (PC) in both hind paws at 1, 2, 4, 24 h and 7 days after both carrageenin injections. The first carrageenin injection induced mechanical allodynia and edema maximal at 240 min (42% reduction of VTPP; 23% increase in PC) and the influence of bupivacaine on the VTPP and PC was similar to previous results (Fletcher et al., 1996). The second ipsilateral carrageenin injection induced a more pronounced inflammation in the control groups and BUPI POST group than the first injection (P < 0.001). In contrast, the increase in allodynia and edema was less intense in the BUPI PRE group than in the other groups (P < 0.0001 and P < 0.02 respectively). Bupivacaine injections had no effect on allodynia and edema related to a second contra-lateral carrageenin injection. These results suggest that bupivacaine infiltration, when administered before the first conditioning injection of carrageenin, can prevent the reinforcement of mechanical allodynia and edema related to a second ipsilateral injection of carrageenin 7 days later.

Analysis of Variance↗
PubMed1997

Antinociceptive effect of bupivacaine encapsulated in poly(D,L)-lactide-co-glycolide microspheres in the acute inflammatory pain model of carrageenin-injected rats.

Encapsulating bupivacaine in poly(D,L)-lactide-coglycolide microspheres may prolong analgesia and diminish systemic toxicity. The antinociceptive effect of bupivacaine-loaded microspheres (1, 2.5, and 5 mg) and plain bupivacaine solutions (1, 2.5, and 5 mg) were compared using the vocalization threshold to paw pressure test (VTPP) in rats. Local anesthetic solutions were injected subcutaneously in the plantar hindpaw. First, the biological inactivity of the vehicle and drug-free microspheres (DFM) was evaluated in normal (n = 8) or carrageenin-injected rats (n = 24). Second, onset of antinociception was evaluated in normal rats (n = 16). We then evaluated the duration of antinociception induced by the different local anesthetic solutions in carrageenin-injected rats (n = 56). Neither the vehicle nor the DFM induced any modification of the VTPP. Onset of antinociception was 5 min for all local anesthetic solutions. Duration of antinociception was 60 min with plain bupivacaine (1 mg) and increased to 90, 120, and 180 min, respectively, for the different doses of bupivacaine-loaded microspheres (1, 2.5, and 5 mg). Larger doses of plain bupivacaine (2.5 and 5 mg) induced systemic toxicity. The encapsulation of bupivacaine in microspheres induced a dose-dependent increase in duration of antinociception as compared with plain bupivacaine.

Acute Disease↗
PubMed1997

Isobolographic analysis of interactions between intravenous morphine, propacetamol, and diclofenac in carrageenin-injected rats.

BACKGROUND: It has been suggested that the combination of analgesic drugs may have additive or synergistic effects. In clinical practice, this might allow better analgesia and reduction of side effects. METHODS: The effects of analgesic drugs were studied in a model of acute inflammatory pain in carrageenin-injected rats using the vocalization threshold to paw pressure. A combination of three different intravenous drugs were used: morphine, diclofenac, and propacetamol, a pro-drug of acetaminophen. The dose-response curves were first obtained for each drug alone. The analgesic potencies of the combinations of morphine and diclofenac (ratios, 1:5.66 and 1:10), morphine and propacetamol (ratio, 1:250), and diclofenac and propacetamol (ratio, 1:65.7) were thereafter evaluated and compared with the effects of the drugs alone. RESULTS: For the two different ratios tested, synergy between diclofenac and morphine was observed only with the higher doses. Propacetamol and morphine or diclofenac and propacetamol combinations were additive for all doses tested. CONCLUSIONS: This study found a synergy between intravenous morphine and diclofenac that is consistent with and helps explain the clinical value of this type of combination in the treatment of acute pain in humans.

Acetaminophen↗
PubMed1996

Effects of local anaesthetics on carrageenan-evoked inflammatory nociceptive processing in the rat.

We have assessed the effects of intraplantar local anaesthetics (bupivacaine and lignocaine) on carrageenan-induced oedema, mechanical allodynia and spinal c-fos protein expression. Mechanical allodynia was evaluated using the vocalization threshold to paw pressure (VTPP) every 30 min until 60, 180 or 240 min after administration of carrageenan. Peripheral oedema, mechanical allodynia and spinal c-fos protein expression were maximal 180 min after carrageenan. Lignocaine did not influence either oedema or VTPP, but reduced spinal c-fos expression at 60 min after carrageenan without later effects. Bupivacaine induced an increase in VTPP at 30 and 60 min, limitation of oedema at 60 min and a reduction in spinal c-fos expression at 60 and 180 min, but these effects were not present 240 min after carrageenan. Intraplantar infiltration with lignocaine and bupivacaine before carrageenan transiently limited signs of inflammatory pain but did not prevent them.

Anesthetics, Local↗
PubMed1996

Influence of timing of administration on the analgesic effect of bupivacaine infiltration in carrageenin-injected rats.

BACKGROUND: Recent evidence has suggested that the timing of administration of analgesic drugs could influence their efficacy by reducing the sensitization of the nervous system induced by the nociceptive inputs, but this concept of preemptive analgesia is still debated in both clinical and basic research. METHODS: The model of acute inflammatory pain induced by carrageenin was used to study the influence of timing of administration of bupivacaine (0.2 ml of a 0.5% solution with 0.005 mg/ml epinephrine) on the development of hyperalgesia, edema, and increase in temperature. The animals received bupivacaine 5 min before (BUPI PRE group, n = 20) or 60 min after (BUPI POST group, n = 20) carrageenin (1 ml/kg of 1% solution) was injected into the left hind paw. Two control groups (n = 15 in each) received saline 5 min before or 60 min after administration of carrageenin. Hyperalgesia of the injected paw was evaluated by the vocalization threshold to paw pressure, edema by measuring paw circumference with a thread, and plantar temperature with a thermocouple thermometer. All measurements were done before carrageenin injection then every 30 min thereafter for 240 min. Another series (n = 24), with the same four groups was also evaluated at 24 h. RESULTS: Local injection of bupivacaine 60 min after carrageenin partially reduced the edema and hyperalgesia. The injection of bupivacaine 5 min before carrageenin was more efficient than the delayed injection and reduced hyperalgesia, edema and the increase in temperature temporarily, but did not totally prevent their development. All groups were similar at 240 min and 24 h. CONCLUSIONS: These results show that a slight advantage of infiltration with bupivacaine before injury exists in this carrageenin model of acute inflammatory pain. However, this benefit is limited in time and bupivacaine did not have any preemptive analgesic effect.

Analgesia↗
PubMed1996

[Postoperative analgesia after surgery of the knee].

This review of postoperative analgesia after knee surgery provides a practical approach to the problem. The patient can be hospitalized or undergo day surgery, with different techniques being available for each situation. For day surgery, the intra-articular administration of local anaesthetic and/or opioids, the non-steroidal anti-inflammatory drugs can be used. During hospitalization patient controlled analgesia, epidural analgesia and peripheral nerve blocks as lumbar plexus, femoral or sciatic nerve block can be proposed. It must be emphasized that a combined approach using these different techniques may be useful in order to offer better analgesia and avoid some side effects. Each technique is described with advantages, side effects and practical usage its. The choice, in each professional environment, must be the best analgesic technique which can be performed safely.

Ambulatory Surgical Procedures↗
PubMed1995

Rate of oxygen consumption by parotid atrophic acinar cells from rats fed liquid diet.

Adult male rats were maintained on a nutritionally adequate liquid-diet or laboratory chow and water (control), for 9 days. They were then killed and the parotid glands removed. Enzymatically dispersed acinar-cell preparations were used to study rates of oxygen consumption (QO2) using a Clark oxygen electrode. For both CON and LD cell preparations the basal QO2 was 0.132 (+/- 0.03-0.05) nmol O2 per microgram DNA per min and in each case this was increased approx. 2.4-fold under stimulation by carbachol (10 microM) and approx. 3.1-fold by adrenaline (10 microM). Isoprenaline (10 microM) elicited no significant increase in QO2. Addition of ouabain (2.5 mM) or removal of Ca2+ from the extracellular medium prevented the action of carbachol to increase QO2 over a sustained period. There were no significant differences in the basal, agonist-stimulated, or ouabain-sensitive QO2 by dispersed acinar cells from liquid-diet rats compared to control. The results are consistent with the notion that liquid diet-induced atrophy represents a physiological adaptation rather than a pathological change. Nevertheless, they also indicate that in the acinar cells from liquid-diet rats the Na+/K+ ATPase is required to operate at normal levels of energy consumption despite the reduced acinar-cell volume and consequently lower levels of agonist-elicited transepithelial ion movements known to occur in these cells.

Animal Feed↗
PubMed1995

Influence of timing on the analgesic effect of intravenous ketorolac after orthopedic surgery.

This study evaluated the pre-emptive analgesic effect of intravenous (i.v.) ketorolac (KET) for total hip replacement (THR). Sixty patients who underwent surgery for THR under general anesthesia were randomly allocated to 3 groups. Two i.v. injections were administered: one before induction and one after surgery. The patients were studied prospectively in a double-blind manner. The control group (CONT; n = 20) received 2 ml of normal saline (NS) for both injections. The pre-operative KET group (PRE; n = 20) received 60 mg of KET and then 2 ml of NS. The postoperative KET group (POST; n = 20) received 2 ml of NS and then 60 mg of KET. General anesthesia was standardized with a intra-operative cumulated dose of fentanyl limited to 4 micrograms/kg. In the recovery room (RR), pain was controlled with an i.v. tritration of morphine; thereafter, on the surgical ward, patients used a patient-controlled analgesia (PCA) pump (Abbott). Pain was evaluated with a visual analogue scale (VAS) at rest and movement in the RR, then every hour for 6 h and every 6 h for 5 days. The side effects monitored were: sedation, respiratory depression, nausea, perioperative bleeding. The patients and surgery were similar for the 3 groups. Upon arrival in the RR, VAS scores taken at rest and at movement were lower for the PRE group than for the CONT and POST groups. Otherwise, VAS scores were similar in all 3 groups. The cumulative dose of morphine in the PRE group was lower than that for the CONT and POST groups from 0 to 6 h.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

Resistance to fever induction and impaired acute-phase response in interleukin-1 beta-deficient mice.

We used gene targeting in embryonic stem cells to introduce an IL-1 beta null allele in mice. The IL-1 beta-deficient mice develop normally and are apparently healthy and fertile. The IL-1 beta null mice responded normally in models of contact and delayed-type hypersensitivity or following bacterial endotoxin LPS-induced inflammation. The IL-1 beta-deficient mice showed equivalent resistance to Listeria monocytogenes compared with wild-type controls. In contrast, when challenged with turpentine, which causes localized inflammation and tissue injury, the IL-1 beta mutant mice exhibited an impaired acute-phase inflammatory response and were completely resistant to fever development and anorexia. These results highlight a central role for IL-1 beta as a pyrogen and a mediator of the acute-phase response in a subset of inflammatory disease models, and support the notion that blocking the action of a single key cytokine can alter the course of specific immune and inflammatory responses.

Acute-Phase Reaction↗