A 1-year Clinical and Radiographic Assessment of Regenerative Endodontic Therapy for Necrotic Primary Molars: A Randomized controlled Trial.

Background: Preservation of necrotic primary teeth is important. Pulpectomy is the gold standard treatment in this situation. Reinfection is the main cause of failure in pulpectomy. The application of regenerative endodontic therapy in mature teeth has the rationale of restoring dental-pulp-like tissue and preventing reinfection. Aims and objectives: The current study was designed to clinically and radiographically assess regenerative endodontics therapy in necrotic primary molars in comparison to zinc oxide eugenol (ZOE) pulpectomy. Materials and methods: A double-blinded randomized controlled trial with three parallel arms and a 1:1:1 allocation ratio was conducted. A total of 54 necrotic primary molars in 39 healthy children aged 4-7 years old were randomly allocated as follows group I-control group, in which ZOE pulpectomy was performed. Group II and III-experimental groups, in which regenerative endodontic therapy (RET) was performed. Modified triple antibiotic paste (mTAP) and Metapex™ were used as intracanal medicaments in groups II and III, respectively. Clinical and radiographic assessments were recorded at baseline, 6 and 12 months. Chi-squared and Fisher's exact tests were used to compare the qualitative data, while Friedman's test was used to study the changes by time within each group. Results: Nonstatistically significant differences were reported between the three groups at the 6 and 12 months follow-ups regarding the clinical or radiographic assessment (p-value = 0.327 and effect size = 0.22), (p-value = 0.055 and effect size = 0.118), respectively. Conclusion: Regenerative endodontic therapy (RET) yielded comparable results to pulpectomy. However, the use of 5 mg/mL mTAP in RET represented the highest level of clinical as well as radiographic insignificant failure. Clinical significance: Regenerative endodontic therapy (RET) provides an acceptable biological alternative to pulpectomy. Trial registration: The protocol was registered at ClinicalTrial.gov with the registration number (NCT04190914). 12/5/2019. How to cite this article: Abdelmoneim DD, Abdelaziz AM, Allam GG, et al. A 1-year Clinical and Radiographic Assessment of Regenerative Endodontic Therapy for Necrotic Primary Molars: A Randomized controlled Trial. Int J Clin Pediatr Dent 2023;16(2):295-301.

Anti-Bacterial effect, fluoride release, and compressive strength of a glass ionomer containing silver and titanium nanoparticles.

Background: Many attempts have been made to enhance the anti-cariogenic properties of the conventional glass ionomer through incorporation of variable materials. However, most importantly, the incorporation of such materials should not jeopardise the physical or mechanical properties of the final restoration. Aims: To investigate the effect of adding silver nanoparticles (Ag-NPs) and titanium dioxide nanoparticles (TiO2-NPs) to conventional glass ionomer cement (GIC) on its anti-bacterial effect against Streptococcus mutans (S. mutans), fluoride ion release, and compressive strength (CS). Settings and Design: This study was an in vitro investigation where 30-disc specimens were prepared in each of the three studied groups. Materials and Methods: The specimens were categorized into the control group (Group C), in which conventional GIC was used, and Group Ag and Group Ti, in which 5 wt% of Ag-NP and TiO2-NP were added, respectively, to GIC powder. In each group, the anti-bacterial effect against S. mutans, fluoride ion release at 24 hours and 14 and 28 days, and CS were assessed. Data were analysed using one-way analysis of variance, followed by Tukey honest significant difference post-hoc test. Results: Both Ag and Ti groups showed a significantly higher anti-bacterial effect than the control group. Ag-NP increased fluoride ion release, whereas TiO2-NP decreased fluoride release; however, cumulative ion release of both experimental groups did not differ significantly compared to the control group. Adding Ag-NP and TiO2-NP increased CS, yet only the Ti group showed the highest CS mean value that was statistically significant compared to other groups. Conclusions: Adding 5 wt% TiO2-NP or Ag-NP to conventional GIC significantly increased its anti-bacterial effect and its CS without affecting fluoride release.

Thymoquinone Crosstalks with DR5 to Sensitize TRAIL Resistance and Stimulate ROS-Mediated Cancer Apoptosis.

OBJECTIVE: Cancer treatment using a targeted inducer of apoptosis like tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) faced the obstacle of resistance, thus providing a plus drug like Thymoquinone (TQ) could be of great interest to tackle breast cancer cells. The aim of the present work is to examine the genetic modulation impacts of the TRAIL receptors and apoptotic markers upon the combinatorial remedy of TRAIL plus TQ on human breast cancer cell lines. METHODS: To achieve this rationale, the protein content-based cytotoxicity using SRB assay, as well as the genetic expressions of the TRAIL receptors (DR4 and DR5) and apoptotic markers (Bcl-2, Cas-8, and FADD) using real time qRT-PCR technique were preceded against breast cancer MCF-7 and MDA-MB-231 cancerous cell lines. RESULTS: The current study showed that the combination therapy of TQ+TRAIL significantly inhibited the protein content-based proliferation of MDA-MB-231 cells more than MCF-7 cells. The synergistic effect of them significantly up-regulated the genetic expressions of DR4, DR5, Cas-8, and FADD genes and inhibited the genetic expression of the Bcl-2 gene in the proposed cell lines treated for 24 h. The induction of the apoptotic genes using the combined therapy was stimulated by the elevation of the reactive oxygen species (ROS); nitric oxide (NO) and malondialdehyde (MDA) levels. CONCLUSIONS: The synergistic influence between TQ which induced the DR5 and TRAIL, facilitating the connection between TRAIL and its receptors on the cancerous cell membrane. Hence, the proposed combination therapy induced the ROS-mediated apoptotic stimulus.

Combination Therapy of TRAIL and Thymoquinone Induce Breast Cancer Cell Cytotoxicity-Mediated Apoptosis and Cell Cycle Arrest.

OBJECTIVE: Cancer is one of the leading causes of mortality in both developed and developing nations. The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is characterized by its ability to selectively trigger apoptosis in cancer cells. TRAIL-based interventions have led to the development of recombinant human (rhTRAIL) as a promising therapy for different types of human cancer. Thymoquinone (TQ) has been shown to exert anticancer effect. The aim of the current study is to investigate the anticancer effect of the combinatorial therapy of TRAIL+TQ against human breast cancer cells. METHODS: To achieve this hypothesis, cytotoxicity using MTT assay, as well as apoptosis and cell cycle using flow cytometric technique were preceded against breast cancer MCF-7 and MDA-MB-231 cancerous cell lines. RESULTS: The current study showed that TRAIL induced cell cycle arrest and apoptosis. Moreover, it inhibited proliferation of MDA-MB-231 cells more than MCF-7 cells. Adding TQ to TRAIL increased the chemo-sensitivity of MDA-MB-231, while overcame the MCF-7 resistance to TRAIL. CONCLUSION: In conclusion, there is a synergistic effect between TRAIL and TQ playing a therapeutic role in killing resistant breast cancer cells.

Proficiency of Carboxymethylcellulose as a Cryoprotectant. Clinical and Histological Evaluation of Cryopreserved Heterogenous Mesenchymal Stem Cell-Exosomal Hydrogel on Critical Size Skin Wounds in Dogs.

Background: Fresh stem cell exosomes are usually obtained and reused in the same individual. It cannot be kept viable for a long period of time regardless of the lengthy preparation time. Freezing is typically used to preserve the viability of perishable materials and increase their lifetime. Regrettably, normal freezing of biomaterials leads to cell damage. Therefore, a cryoprotectant can save the cells from the conventional cryodamage. Sodium carboxymethylcellulose (NA-CMC) is a powdery substance that is used to manufacture bio-safe hydrofilm gels because of its high viscosity, cytocompatibility, and nonallergenic nature. Materials and Methods: Sterile CMC hydrogel was prepared, part of which was loaded with exosomal solution derived from MSCs. The gel was kept at -20°C for preservation. Two bilateral full-thickness circular skin wounds of 2-cm diameter were created on the back of experimental dogs. The wounds were at least 2.5 cm apart. Treatment started 24 hours after wound creation. Group I received CMC gel solely, whereas group II received frozen CMC exosomal gel. The gel was applied 4 times, a single application per day with 1- day interval. Results: Clinically, the frozen exosomal gel significantly promoted wound healing with no scaring. Histologically, enhanced dermal fibroblasts and organized collagen deposition were seen in the treated group. Conclusion: CMC proved to be an efficient cryoprotectant and a suitable vehicle for exosomes. Deep freezing was proven to conserve the viability, extended the preservation, and facilitated the usage of exosomal gel. This technique of preserved cell-free therapy is inexpensive, time-saving, and proficient and seems suitable for treating cutaneous wounds.

Caries Experience Varies in Egyptian Children With Different Combinations of Cleft Lip and Palate and Is Related to Carbohydrate Intake Between Meals.

OBJECTIVES: Our aim was to assess the prevalence of dental caries in Egyptian children with cleft lip or cleft lip and palate (CLP), according to dietary habits, and to assess the level of dental care given to these patients. DESIGN: Children aged 4 to 12 years (N = 120) with CLP were recruited: 54 with primary dentition and 66 with mixed dentition. Personal data were gathered and parents completed a 5-day diet diary for the children. The prevalence of dental caries was determined with the dmft and DMFT indices, and debris and calculus were assessed with the simplified oral hygiene index. RESULTS: Of this, 16.7% of children were caries-free. Caries experience was directly correlated with the intake of carbohydrate-containing items between meals, but not with intake at meal times. Oral-hygiene (debris) status did not differ significantly between the CLP groups. Calculus was found in 6.6% of the children. Only 8.3% of the study population had received oral-hygiene instructions from a health care professional. CONCLUSION: A direct correlation was found between caries experience and the intake of sugar-containing items in-between meals, indicating the importance of dietary advice into the comprehensive dental management of patients with CLP. Our sample had not received effective dental services.

Human Parvovirus B19 Infection in Rheumatoid Arthritis Patients: Screening and Clinical Significance.

Rheumatoid arthritis (RA) is a common chronic inflammatory disease, affecting about 1% of the general population. Conflicting data are available regarding the etiologic association of human parvovirus B19 (B19) infection with RA. This study aimed to determine the prevalence of B19 infection in patients with RA compared to healthy controls and to assess its possible association with disease activity or severity. The study included 40 RA patients and 40 age and sex matched apparently healthy controls. Detection of B19 DNA by nested PCR and the detection of anti-B19 IgM and IgG by ELISA) were performed for patients and controls. It was found that B19 infection is more prevalent in patients with RA than healthy controls as the frequency of detection of B19 DNA and anti-B19 IgG was significantly higher in RA patients than healthy controls (P=0.003 and P=0.04, respectively) but not IgM. It was concluded that B19 infection may have a role in the etiopathogenesis of RA but not involved in disease activity or severity.

Histological Evaluation of Experimentally Induced Critical Size Defect Skin Wounds Using Exosomal Solution of Mesenchymal Stem Cells Derived Microvesicles.

BACKGROUND AND OBJECTIVES: The present study investigated whether MSCs derived microvesicles (MVs) or (Exosomes) can exert therapeutic effects on an experimental model of cutaneous injury and explored the underlying involving mechanisms. METHODS AND RESULTS: Three bilateral full thickness circular wounds were created on the back of two groups of dogs using 2-cm dermal punch. The wounds were at least 2.5 cm apart. Saline was subcutaneously injected in 4 places around each wound area in group-I (control), whereas an equal volume of exosomal solution of MSCs derived MVs was similarly injected in group-II. The findings demonstrated that MSCs derived MVs had significantly promoted cutaneous wound healing, collagen synthesis, and vascularization at wound sites. The application of the exosomal solution had not only promoted the generation of newly formed vessels, but also have accelerated their development and maturation leading to a faster healing process. CONCLUSIONS: MSC-Exosomes appeared to be a superior candidate for treating cutaneous wounds than their originator cells, and may represent a promising opportunity to develop a novel cell-free therapy approach that might overcome the obstacles and risks associated with the use of native or engineered stem cells transplantation therapy.

Histological Evaluation of Experimentally Induced Critical Size Defect Skin Wounds Using Exosomal Solution of Mesenchymal Stem Cells Derived Microvesicles

BACKGROUND AND OBJECTIVES: The present study investigated whether MSCs derived microvesicles (MVs) or (Exosomes) can exert therapeutic effects on an experimental model of cutaneous injury and explored the underlying involving mechanisms. METHODS AND RESULTS: Three bilateral full thickness circular wounds were created on the back of two groups of dogs using 2-cm dermal punch. The wounds were at least 2.5 cm apart. Saline was subcutaneously injected in 4 places around each wound area in group-I (control), whereas an equal volume of exosomal solution of MSCs derived MVs was similarly injected in group-II. The findings demonstrated that MSCs derived MVs had significantly promoted cutaneous wound healing, collagen synthesis, and vascularization at wound sites. The application of the exosomal solution had not only promoted the generation of newly formed vessels, but also have accelerated their development and maturation leading to a faster healing process. CONCLUSIONS: MSC-Exosomes appeared to be a superior candidate for treating cutaneous wounds than their originator cells, and may represent a promising opportunity to develop a novel cell-free therapy approach that might overcome the obstacles and risks associated with the use of native or engineered stem cells transplantation therapy.

Fluid optimization with hydroxyethyl starch 130/0.4 compared with modified fluid gelatin guided by esophageal Doppler during major abdominal surgeries.

Perioperative fluid therapy has a direct bearing on patient outcome and accordingly should be tailored individually. Thus the efficacy of HES 130/0.4 was compared to modified fluid gelatin for volume expansion during major abdominal surgery guided by transesophageal Doppler (TED). Fifty adult patients ASA physical status I-II undergoing major abdominal surgery were anesthetized with standard technique. In addition to basal fluid requirement, patients were randomly allocated into two equal groups (25 patients each) to receive 200 cc of either 6% HES 130/0.4 (HES group) or 3% modified fluid gel (GEL group) as intraoperative colloid replacement guided by TED. Heart rate, mean arterial blood pressure, central venous pressure, and Doppler derived measurements were recorded at the following timings: T1; after induction, T2; after skin incision, T3; two hours after that and T4; at the end of surgery. Fluid administration and transfusion requirements were recorded. Laboratory tests for hemostasis, hepatic and renal functions were continued till the fifth postoperative day. Both groups were comparable regarding Doppler derived data and fluid balance. Platelet count showed a significant drop (p < 0.05) in group GEL in all postoperative days compared with baseline and with the group HES. Prothrombin time and INR showed a significant increase while prothrombin concentration showed a significant drop, throughout 5 postoperative days in group HES while in the 3 postoperative days in group GEL (p < 0.05) but comparable between groups. Both groups showed postoperative drop in creatinine level and postoperative rise of liver function tests. HES 130/0.4 and modified gelatin have comparable fluid optimization effect guided by TED in major abdominal surgeries. HES 130/0.4 has a more favorable effect on platelet counts than modified gelatin.

In vivo effects of different anesthetic agents on apoptosis.

BACKGROUND: This study was designed to measure in vivo effects of propofol, isoflurane and sevoflurane on apoptosis by measuring caspase-3 and tumor necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL) blood level as apoptotic markers. METHODS: After obtaining ethical committee approval and informed written consents, sixty adult patients ASA I scheduled for open cholecystectomy participated in this study. They were randomally allocated into one of three equal groups to receive propofol infusion, low-flow isoflurane or sevoflurane for maintenance of anesthesia. Venous blood samples were collected preoperatively, immediately postoperative and after 24 hours to measure hemoglobin, hematocrit, creatinine, liver enzymes, serum TRAIL and caspase-3 levels. RESULTS: There was no significant difference in hematological markers and serum creatinine. Liver enzymes showed significant postoperative rise (P < 0.05). In Propofol group, TRAIL and caspase-3 levels were significantly elevated immediately postoperative then decreased significantly after 24-hours (P < 0.05). In Isoflurane group, immediate postoperative level of TRAIL was significantly higher than 24 hours reading and significantly lower than its level in Propofol group at the same timing meanwhile caspase-3 levels were comparable at different timings. In Sevoflurane group, TRAIL and caspase-3 levels increased significantly in both postoperative samples than preoperative level and than those of Isoflurane and Propofol groups after 24 hours concerning TRAIL (P & 0.05). CONCLUSIONS: This study concluded that isoflurane is superior and sevoflurane is the least effective among the three anesthetics in protection against apoptosis. This study neither proved nor excluded propofol-induced apoptosis. Further studies are required during lengthy procedure and in compromised patients.

Role of T helper 17 cells in the pathogenesis of systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a multi-organ autoimmune disorder that occurs in genetically prone individuals. Autoimmunity could not be simply explained by Th1/Th2 cell paradigm. T helper 17(Th17) cells producing the cytokine interleukin-17 (IL-17) may explain the promotion and progression of autoimmune phenomena. This study aimed to investigate the role of Th17cells, IL-17 and interleukin-23 (IL-23) in the pathogenesis of SLE and their correlation with disease activity. The frequencies of circulating Th17 cells in 15 patients with active SLE, 15 patients with inactive disease and 15 healthy control subjects were measured using Flowcytometry after stimulation with phorbol myristate acetate (PMA) and ionomycin for 4 hours. Serum levels of IL-17 and IL-23 were measured using the enzyme linked immunosorbent assay (ELISA). Significantly higher mean frequencies of circulating Th17 cells were found in active SLE patients (1.54 +/- 0.38%, P < 0.001) and inactive SLE patients (1.23 +/- 0.25%, P = 0.009) compared to the control group (0.88 +/- 0.41%). The frequencies of circulating Th17 cells positively correlated with the SLEDAI score (r = 0.812, P < 0.001). The serum levels of IL-17 and IL-23 were significantly higher in active SLE (P < 0.001) and inactive SLE patients (P < 0.001) than the control group while, serum levels of both cytokines correlated positively with SLEDAI score (r = 0.661, P < 0.01 and r = 0.701, P < 0.01 respectively). There was significant positive correlation between the frequency of circulating Th17 cells and plasma levels of IL-17 and IL-23 (r = 0.789, P < 0.001) and (r = 0.792, P < 0.001) respectively. Results of this study provides evidence of a role of Th17 cells in the pathogenesis of SLE, and offer scientific rationale for the utility of Th17 cells, IL-17 and IL-23 as biological markers for SLE disease activity. This would raise the possibility of anti-IL-17 and anti-IL-23 as innovative therapeutic options in controlling disease activity of SLE.

In vivo effects of different anesthetic agents on apoptosis / 대한마취과학회지

BACKGROUND: This study was designed to measure in vivo effects of propofol, isoflurane and sevoflurane on apoptosis by measuring caspase-3 and tumor necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL) blood level as apoptotic markers. METHODS: After obtaining ethical committee approval and informed written consents, sixty adult patients ASA I scheduled for open cholecystectomy participated in this study. They were randomally allocated into one of three equal groups to receive propofol infusion, low-flow isoflurane or sevoflurane for maintenance of anesthesia. Venous blood samples were collected preoperatively, immediately postoperative and after 24 hours to measure hemoglobin, hematocrit, creatinine, liver enzymes, serum TRAIL and caspase-3 levels. RESULTS: There was no significant difference in hematological markers and serum creatinine. Liver enzymes showed significant postoperative rise (P < 0.05). In Propofol group, TRAIL and caspase-3 levels were significantly elevated immediately postoperative then decreased significantly after 24-hours (P < 0.05). In Isoflurane group, immediate postoperative level of TRAIL was significantly higher than 24 hours reading and significantly lower than its level in Propofol group at the same timing meanwhile caspase-3 levels were comparable at different timings. In Sevoflurane group, TRAIL and caspase-3 levels increased significantly in both postoperative samples than preoperative level and than those of Isoflurane and Propofol groups after 24 hours concerning TRAIL (P & 0.05). CONCLUSIONS: This study concluded that isoflurane is superior and sevoflurane is the least effective among the three anesthetics in protection against apoptosis. This study neither proved nor excluded propofol-induced apoptosis. Further studies are required during lengthy procedure and in compromised patients.

[Reporting of muscle relaxant effects in anaesthesia files concerning visceral surgery - a observational and multicenter study]. / Traçabilité de la gestion de l'utilisation des curares dans le dossier d'anesthésie en chirurgie viscérale : une étude observationnelle et multicentrique.

OBJECTIVES: To report any item documenting the peroperative muscle relaxant effects management in anaesthesia files issued from visceral surgery processes. TYPE OF STUDY: Prospective, observational and multicenter. PATIENTS AND METHODS: A single operator analysed 1453 files proposed by nine anaesthetists' teams. The items selected concerned three periods: induction/tracheal intubation, paralysis maintenance, tracheal extubation. Reporting of 40 categories of items was studied. RESULTS: Items related to laryngoscopy and intubation conditions were observed in 43% (0-95) [general average (intercentres min-max)] and in 11% (0-97) of the files, respectively. At least one level of paralysis was reported in 23% (0-96) of the files. For the paralysis maintenance, documentation of an effect appeared in 53% (4-96) of the documents. Neuromuscular assessments preceding the tracheal extubation were retrieved in 43% (12-89) of the notes. Adductor pollicis was concerned for 30% (1-89) of these observations. Detection of level of spontaneous paralysis offset, satisfying to the local standard, appeared in 14% (3-19) of the documents. Pharmacological reversal was noted for 25% (4-67) of the patients; the assessment of the effects so produced was reported in 8% (0-58). CONCLUSION: In the studied collection, the traceability of the peranaesthetic curarization management appears variable on both qualitative and quantitative levels. The emergence of a dedicated guideline - defining the criteria for producing a good documentation of the muscle relaxant use - becomes necessary to secure these practices for all physicians using muscle relaxants.

[Anaesthetic preoperative assessment of chronic medications and herbal medicine use: a multicenter survey]. / Traitement médicamenteux et phytothérapie des patients adressés en consultation d'anesthésie: enquête multicentrique.

OBJECTIVE: This study was undertaken to quantify the use of chronic medication and herbal remedies in the presurgical population. STUDY DESIGN: Prospective multicenter survey. PATIENTS AND METHODS: Adult patients presenting for anaesthesia were directly asked if they were currently using chronic medication or herbal remedies. RESULTS: Among 1057 patients (age 54+/-17 yrs, woman 54%, ASA 2 [1-4], 74%) were taking one or more chronic medication. The most commonly used treatments were, in descending order angiotensin-converting enzyme inhibitors and angiotensin-II receptor blockers (15%), beta blockers (11%) and platelet inhibitors (10%). Also, 9% were taking one or more of the following herbal remedies known to interact with the perioperative period: valeriane, ginseng, ginkgo, St John's wort, echinacea and ephedra. Women and patients aged 40-70 yr were most likely to be taking a herbal product (p<0.001 and p<0.01 respectively). CONCLUSION: Chronic medication and herbal remedies are common in patients presenting for anaesthesia. Because of the potential interactions between anaesthetic drugs or techniques and such medication it is important for anaesthetists to be aware of their use.

Postoperative residual neuromuscular block: a survey of management.

BACKGROUND: To avoid postoperative residual neuromuscular block there is a need for a change in clinician's attitude towards monitoring and reversal. This study aims to evaluate changes of perioperative neuromuscular block management during the last decade in our institution and to quantify the incidence of postoperative residual neuromuscular block. METHODS: Patients receiving intermediate-acting neuromuscular blocking agents for scheduled surgical procedures during 3-month periods in 1995 (n=435), 2000 (n=130), 2002 (n=101), and in 2004 (n=218) were prospectively and successively enrolled in our study. The management of neuromuscular block in the operating room and the adequacy of the recovery were at the discretion of the anaesthesiologist. An attempt was made between each study period to promote a change in the management of neuromuscular block. In the post-anaesthesia care unit, train-of-four (TOF) stimulations were used to assess the presence of a residual neuromuscular block. RESULTS: Between 1995 and 2004 quantitative measurement and reversal of neuromuscular block in the operating room increased from 2 to 60% and from 6 to 42%, respectively (P<0.001). During the same time, the incidence of residual neuromuscular block defined as a TOF ratio less than 0.9 decreased from 62 to 3% (P<0.001). Use of objective neuromuscular monitoring and/or anticholinesterase drugs was less likely in patients with an inadequate recovery (P<0.001). CONCLUSIONS: During the last decade the incidence of residual neuromuscular block strongly decreased in our institution. It confirms the positive impact of neuromuscular monitoring and reversal of neuromuscular block in routine anaesthetic practice.

Residual curarization in the recovery room after vecuronium.

We have investigated residual block after anaesthesia which included the use of the neuromuscular blocking agent vecuronium but no anticholinesterase, in 568 consecutive patients on admission to the recovery room. The ulnar nerve was stimulated submaximally using TOF stimulation (30 mA). Postoperative residual curarization was defined as a TOF ratio < 0.7. Of the 568 patients, 239 (42%) had a TOF < 0.7 in the recovery room. These patients had received a larger cumulative dose of vecuronium than patients who had full recovery (mean 7.7 (SD 3.6) mg vs 6.2 (2.7) mg; P < 0.05) and a shorter time had elapsed since the last vecuronium dose (117 (70) min vs 131 (80) min; P < 0.05). Of 435 patients whose trachea was extubated, 145 (33%) exhibited inadequate recovery from neuromuscular block. Six of these had one or no response to TOF stimulation and were reintubated. In the remaining 139 patients, neuromuscular block was successfully antagonized. Only 20 patients (3.5%) remembered TOF stimulation when questioned 2 h later in the recovery room, and discomfort associated with it was assessed using a visual analogue scale before discharge. We conclude that it is necessary to antagonize residual block produced by vecuronium.

Optimal dose of lignocaine for preventing pain on injection of propofol.

The purpose of this study was to define the optimum dose of lignocaine required to reduce pain on injection of propofol. We conducted a prospective, randomized, double-blind trial on 310 patients undergoing anaesthesia. Patients were allocated to four groups according to the lignocaine dosage: group A (control), no lignocaine; group B, lignocaine 0.1 mg kg-1; group C, lignocaine 0.2 mg kg-1; group D, lignocaine 0.4 mg kg-1. Our results showed that a dose of lignocaine 0.1 mg kg-1 significantly reduced the incidence of pain and that there was no improvement when the dose was increased.

[A nicardipine-isoflurane combination in the microsurgery of the middle ear]. / Association nicardipine-isoflurane dans la microchirurgie de l'oreille moyenne.

Middle ear microsurgery requires a bloodless operative field, achieved through deliberate hypotension techniques. The present work was designed to analyze the quality of the deliberate hypotension induced by the combination of isoflurane with nicardipine, an injectable calcium channel blocker. Eleven patients, ASA I, 10 minutes after induction of anaesthesia, received nicardipine as a bolus of 25 mg renewed every five minutes (maximum 4) and as a perfusion (5 mg/hour). The bloodless operative field was excellent in all cases with a 29.7% drop in arterial blood pressure after 15 minutes (heart rate: +22.3% after 25 min); values then remained stable until nicardipine was stopped; then hemodynamic data returned to the preanaesthetic values in 66 +/- 56 minutes. No side effect was registered. As a conclusion, deliberate hypotension induced by isoflurane--nicardipine combination provides good conditions for middle ear microsurgery.