Continuous intraarticular and periarticular levobupivacaine for management of pain relief after total knee arthroplasty: A prospective randomized, double-blind pilot study

BACKGROUND

Total knee arthroplasty (TKA) can result in major postoperative pain which can impact the recovery and rehabilitation of patients and for this reason the use of a pain-control infusion pumps (PCIP) enhances analgesia for TKA.

PURPOSE

To investigate whether a PCIP of levobupivacaine would reduce pain in patients following TKA.

METHODS

This was a prospective, randomized, controlled study conducted in 55 patients. Criteria for participation were unilateral TKA for osteoarthritis and no allergies to levobupivacaine. The primary outcomes measured were postoperative pain intensity on Visual Analogue Scale (VAS) score measured at 24 h and 48 h. Other measures included amount of narcotics, presence of adverse events, and length of hospital stay.

RESULTS

PCIP-treated patients (n = 28) showed significant reductions in VAS score at any time versus control (p < 0.01). Amount of narcotics, presence of adverse events, and length of hospital stay were significantly less with the PCIP versus control (each p < 0.01).

CONCLUSION

The use of a mix of levobupivacaina, ketoral-trometamina, and adrenalin provides a safe and effective means in post-operative pain relief in patients undergoing TKA.

LEVEL OF EVIDENCE

Level II therapeutic study.

Simultaneous calorimetric and polarization microscopy investigations of light induced changes over phase transitions in a liquid crystal-napthopyran mixture

We have studied the specific heat and the thermal conductivity in a 4-(n-octyl)-4'-cyanobiphenyl liquid crystal (LC)-photochromic molecules mixture, before, during, and after the photo-activation of the dispersed photochromic molecules, over both the smectic A-nematic and the nematic-isotropic phase transitions. The evaluation of the specific heat has enabled the determination of the changes of the phase transition characteristics induced by the photochromic molecules photoisomerization, while that of the thermal conductivity could be used to monitor the modifications induced in the average LC molecular orientation. The polarization microscopy imaging of the sample texture constituted a valuable support for the interpretation of the obtained thermal conductivity results.

Dual beam differential photopyroelectric setup for broadband thermal effusivity investigation of glass transitions in polymers

The behaviour of the thermal effusivity squared over the glass transition in polystyrene is measured over a considerable frequency range using a novel dual beam front detection photopyroelectric configuration, which ensures a very effective processing of the obtained signal. This has enabled the detection of the very small changes taking place in such a parameter, despite the non-favourable sensitivity conditions due to the large mismatch between the thermal effusivities of the pyroelectric transducer and of the sample. The effect of the thermal contact resistance between the sample and the pyroelectric detector is also considered and discussed.

Study of the smecticA-hexaticB phase transition in homeotropic single domain samples of 65OBC liquid crystal by photopyroelectric calorimetry

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Study of the refractive index of microscopic glass beads by light-refraction analysis

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Polarization-resolved nondegenerate two-wave mixing in shaped microparticle suspensions

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Birefringence and scattering in highly oriented artificial Kerr media

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Polarization-resolved optical phase conjugation in an artificial anisotropic Kerr medium

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Third-order nonlinearity enhancement in an artificial Kerr medium through bulk intrinsic birefringence

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