Hypobaric bupivacaine for continuous spinal anesthesia in elderly hip fracture: Effects on hemodynamic (A randomized controlled trial).

INTRODUCTION: Continuous spinal anesthesia for surgical repair of hip fracture in elderly patients has been shown to preserve hemodynamics better than general and single shoot spinal anesthesia. However, hypotension still occurs, even with continuous spinal anesthesia. AIM: This study aimed to demonstrate that hypobaric bupivacaine is more effective in preserving hemodynamics than isobaric bupivacaine when patients are operated in lateral position. METHODS: It was a prospective randomized controlled single-blind study conducted in an orthopaedic institute during two years (2017-2018). One hundred and ten patients aged more than 65 years, scheduled for hip fracture repair, were randomized to receive either hypobaric or isobaric bupivacaine. Repeated doses of 2.5 mg bupivacaine were injected until sensory blockade reached T12. Hypotension and severe hypotension were defined as a decrease of more than 20% and 30% from the baseline systolic arterial blood pressure and were treated with ephedrine. Statistical analysis used Chi2 and Student tests to compare either number and percentage or mean and median. P<0.05 was significant. RESULTS: Less patients experienced hypotension and severe hypotension in hypobaric group than in isobaric group (respectively 53% vs. 73%; p<0.05 and 22% vs. 53%; p< 0.01). Ephedrine consumption was significantly lower in hypobaric group (1.9 mg vs. 5.6 mg; p<0.01). CONCLUSION: Hypobaric bupivacaine may be used rather than isobaric bupivacaine for further preserving hemodynamics in continuous spinal anesthesia for hip fracture surgery in elderly.

Preoperative hypnosis for pain management after arthroscopic repair of anterior cruciate ligament.

BACKGROUND: The practice of hypnoanalgesia in orthopedics is rare and the literature is poor. AIM: The purpose of this pilot study was to verify the efficacy of hypnosis for the management of postoperative analgesia after arthroscopic repair of anterior cruciate ligament. METHODS: This was a prospective clinical trial over a period of 6 months (March - August 2015) including 25 patients scheduled for arthroscopic repair of anterior cruciate ligament under spinal anesthesia. All these patients had preoperative hypnosis in addition to the standard multimodal analgesia protocol (group H) and were compared to historical group (group S) who received only a standard multimodal analgesia protocol. RESULTS: Pain scores were significantly lower for the hypnosis group during the first 48 hours postoperatively (p = 0,006). The total dose of morphine at 48 hours was: 13,6 mg (95% CI [4,58; 22,62]) in the group H and 10,2 mg (95% CI [1,64 ; 18,76]) in group S with no statistically significant difference (p = 0,178) Conclusion: Results of this pilot study in orthopedic surgery suggested that hypnosis reduced postoperative pain scores as demonstrated in other surgeries.

Adductor canal block: Effect of volume of injectate on sciatic extension.

CONTEXT: Spread of local anesthetic within adductor canal to peroneal and tibial nerves is described in literature. This spread could be volume-dependent. AIMS: In this study, we compared the diffusion of two volumes of 0.375% ropivacaine to popliteal fossa. SETTINGS AND DESIGN: This was a prospective, randomized controlled, single-blind study conducted in Kassab Orthopaedic Institute of Tunis for 1 year (2018). MATERIALS AND METHODS: A total of 42 patients, American Society of Anesthesiologists I/II scheduled for knee arthroscopy under spinal anesthesia scheduled to receive adductor canal block, were randomized into two groups: group N received 20 mL of ropivacaine 0.375% and group H received 40 mL. We evaluated sensory motor blocks of both peroneal and tibial nerves at 30 and 60 min. STATISTICAL ANALYSIS USED: Chi-square or Fisher's exact test was used to compare the number and percentage. P <0.05 was significant. RESULTS: At 60 min, complete sensory block of the peroneal nerve was obtained for 16 patients in group H versus 15 patients in group N with no statistically significant difference (P = 0.60). The difference was also not significant (P = 0.27) for the tibial nerve: 14 patients for group H versus 16 for group N. Motor blockade was rare in the two nerve territories. CONCLUSION: Spread of 0.375% ropivacaine to popliteal fossa resulted in high rate of complete sensory blockade of both peroneal and tibial nerves. Diffusion of local anesthetic was not volume-dependent.

Perioperative morbidity in total knee arthroplasty.

INTRODUCTION: As the life expectancy and weight of patients are increasing, more old and obese patients are undergoing total knee arthroplasty (TKA). TKA may lead to several perioperative complications. These include anesthesia-related risks, exacerbation of comorbid medical issues and complications of surgical procedure. We have no studies reporting medical complications following TKA among our population. This study aimed to evaluate perioperative complications of TKA and to identify the related risk factors. METHODS: It was a monocentric retrospective including 410 observations in the local TKA registry. Data of patients operated for primary unilateral TKA during the period from January 2014 to December 2017 were reviewed. All patients had standardized protocols of anesthesia and post operative care for three days following surgery. Multivariate logistic regression was used to identify the predicting factors for complications. RESULTS: Incidence of perioperative complications was 37.1%. The most frequent were per operative hypotension (14.1%) and postoperative desaturation (21.7%, including pulmonary embolism in 2.4%). Multivariate logistic regression analysis identified: age ≥ 65 years (OR=1.9; p=0.006), respiratory diseases (OR=1.8; p=0.042) and general anesthesia (OR=2.8; p=0.009) as significant risk factors for any complications. Loss of autonomy (OR=4.8; p <0.001) and general anesthesia (OR=2.6; p=0.03) were significant risk factors for hypotension. Age ≥ 65 years (OR=2.6;p<0.001), female gender (OR=4.3;p=0.006) and respiratory diseases(OR=1.9;p=0.02) were associated with postoperative desaturation. CONCLUSION: This study highlighted hemodynamic and respiratory complications as the most common early complications in TKA. Age ≥ 65years, general anesthesia and respiratory diseases were significant risk factors.

Laser scanning confocal microscopy characterization of water repellent distribution in a sandstone pore network.

In the present work, we propose the use of the Laser Scanning Confocal Microscopy (LSCM) to determine the effect of water repellents on rock's pore-network configuration and interconnection. The rocks studied are sandstones of Miocene age, a building material that is commonly found in the architectural heritage of Tunisia. The porosity quantitative data of treated and untreated samples, obtained by mercury porosimetry tests, were compared. The results show a slight decrease in total porosity with the water repellent treatment, which reduced both microporosity and macroporosity. This reduction produced a modification in pore size distribution and a shift of the pore access size mode interval toward smaller pore diameters (from the 30-40 microm to the 20-30 microm intervals). The water repellent was observed in SEM images as a continuous film coating grain surfaces; moreover, it was easily visualized in LSCM, by staining the water repellent with Epodye fluorochrome, and the coating thickness was straightforwardly measured (1.5-2 microm). In fact, the combination of mercury intrusion porosimetry data and LSCM observations suggests that the porosity reduction and the shift of the pore diameter mode were mainly due to the general reduction of pore diameters, but also to the plugging of the smallest pores (less than 3-4 microm in diameter) by the water repellent film. Finally, the LSCM technique enabled the reconstruction of 3D views of the water repellent coating film in the pore network, indicating that its distribution was uniform and continuous over the 100 microm thick sample. The LSCM imaging facilitates the integration and interpretation of mercury porosimetry and SEM data.

Determination of the distribution of consolidants and interpretation of mercury porosimetry data in a sandstone porous network using LSCM.

Knowing the 3D distribution of a consolidant within the porous network of a rock is essential for understanding the porosity quantitative data obtained by mercury porosimetry and for observing the effect of consolidants on pore interconnection. In this work, we show for the first time that the distribution of consolidant in the porous network can be determined using laser scanner confocal microscopy (LSCM). Results indicate that consolidants are concentrated in pore throats of less than 40 microm in diameter, affecting both the porous interconnection and the circulation of fluids. LSCM allowed demonstration of the fact that the increase in microporosity detected by mercury porosimetry is due to the development of fissures within the consolidants. No consolidant that produces this kind of fissure can be used in the consolidation of building stones, since it would increase microporosity and, in consequence, vulnerability to weathering agents.