Obese parturients have lower epidural local anaesthetic requirements for analgesia in labour

Background. There are no studies comparing local anaestheticrequirements for obese and normal parturients. Obesity has beenassociated with a higher incidence of Caesarean section andhigher levels of epidural block have also been found in obeseobstetric patients, suggesting they may require less local anaesthetic.The aim of our study was to estimate the minimum local analgesicconcentration (MLAC) of bupivacaine for obese and non-obeseparturients. Methods. Otherwise healthy parturients (n=32) requesting epiduralanalgesia were enrolled in this up–down sequential allocationstudy. Women were in active labour (3–6 cm cervical dilatation)with visual analogue pain scores (VAPS) >40/100 mm. Subjectswith BMI >30 kg m^–2 were allocated to the obese groupand BMI     

Unicompartmental knee replacement provides early clinical and functional improvement stabilizing over time

Purpose  

Unicompartmental knee replacement preserves uninvolved osteocartilaginous and soft tissue structures, thereby allowing a more physiological and early clinical and functional recovery. The aim of this study was to report the results of ZUK unicompartmental fixed metal-back prosthesis and how these results change over time.     

Hypersomnolence in fibromyalgia syndrome

OBJECTIVE: To evaluate hypersomnolence in patients affected by fibromyalgia syndrome. METHODS: Thirty consecutive patients affected by fibromyalgia syndrome (FMS) (28 F) completed a sleep questionnaire and underwent the following evaluations: lung function tests; polysomnography; the Epworth sleepiness scale (ESS), which measures sleep complaints and daytime hypersomnolence; and the visual analogical scale (VAS) to detect subjective pain, fatigue, anxiety and depression. RESULTS: The FMS patients were divided into two groups based on their ESS score. Patients complaining of daytime hypersomnolence had a higher number of tender points (15 +/- 2 vs. 12 +/- 1, p < 0.01), a higher subjective pain score (72 +/- 15 vs. 52 +/- 13, p < 0.05), and more fatigue (p < 0.05). The diffusing capacity of the lung (Tlco) was more impaired and the occurrence of periodic breathing was higher. FMS patients complaining of daytime somnolence had significantly less efficient sleep than the FMS patients with no daytime somnolence (p < 0.05), i.e. a lower proportion of stage 3 sleep (5 +/- 2% vs. 12 +/- 3%; p < 0.001), stage 4 sleep (1 +/- 0.5% vs. 4 +/- 1%; p < 0.001), and twice as many arousals per hour of sleep (p < 0.01). The respiratory pattern of FMS patients with hypersomnolence showed a higher occurrence of periodic breathing (p < 0.05). The short length of apneas and hypopnoeas did not affect the apnea/hypopnea index (5.1 +/- 3 vs. 7 +/- 4; ns), but FMS patients with daytime hypersomnolence had a greater number of desaturations per hour of sleep (11 +/- 6 vs. 6 +/- 5; p < 0.05). Pulmonary volumes did not differ between the two groups. The EES score was significantly correlated in FMS patients, and even more markedly in the FMS patients with hypersomnolence, TLco, A/I, and disease duration. The ESS score was correlated significantly with the number of tender points only in FMS patients with daytime hypersomnolence. CONCLUSION: The occurrence of daytime hypersomnolence in FMS patients is linked to a greater severity of fibromyalgia symptoms and to more severe polysomnographic alterations.     

Meniscal allografts: cryopreservation vs deep-frozen technique An experimental study in goats

Meniscal transplantation was performed in two groups of 15 adult goats each, using cryopreserved (group I) and deep-frozen (group II) allografts. Animals were killed at 2 weeks, 1, 3, 6 and 12 months, and a gross, histological and biochemical (water and glycosaminoglycan) evaluation of the menisci was performed. The allografts of both groups showed a normal gross appearance and had in most cases healed at the horn attachments and at the peripheral capsular tissue with a dense scar tissue and no signs of rejection. Histological analysis showed that at 2 weeks in group I the cell number was decreased compared with the controls, and the cells were mainly distributed in the superficial layers. In group II at 2 weeks, only a few cells were present at the peripheral attachment of the menisci. At 1 month in both groups, the cell repopulation can be seen extending from the peripheral area to the superficial layers. Cell proliferation and vascularization are particularly evident in both groups in the 3-month samples. At 6 months and 1 year the grafts can be seen to be completely remodelled and morphologically similar to normal menisci in both groups. Biochemical analysis showed in both groups an increase in water content and a progressive decrease in the concentration of glycosaminoglycans. At 1 year in both groups, there were moderate degenerative changes in the articular cartilage of the tibial plateau, which were more evident in the area of exposed cartilage than in that covered by the meniscus. These results suggest that there are no significant differences between the cryopreserved and deep-frozen grafts, and that even if cryopreservation makes it possible to maintain a partial cell viability in the tissue, this does not seem to improve the morphological and biochemical characteristics of the graft. Received: 11 March 1996 Accepted: 5 February 1997     

Comparative effectiveness of upfront esophagectomy versus induction chemoradiation in clinical stage T2N0 esophageal cancer: A decision analysis

Objectives

We compared the effectiveness of upfront esophagectomy versus induction chemoradiation followed by esophagectomy for overall survival in patients with clinical T2N0 (cT2N0) esophageal cancer. We also assessed the influence of the diagnostic uncertainty of endoscopic ultrasound on the expected benefit of chemoradiation.

Acute patellar dislocation. What to do?

Acute patellar dislocation is a common knee injury that occurs most often in adolescents, frequently associated with sporting and physical activities. Patellar re-dislocation after the first episode appears to depend primarily on the medial patellofemoral ligament injury which represents the primary ligamentous restraint, providing about 50–60 % of the restraining force against lateral patellar displacement. Clinically, up to 94–100 % of patients suffer from medial patellofemoral ligament rupture after first-time patellar dislocation. Controversy regarding how patients with first patellar dislocation should be managed still exists. Though most authors have reported good results with the conservative treatment after a first-time dislocation, several circumstances may warrant surgical intervention. A surgical approach would be necessary in the presence of severe cartilage damage or a relevant disruption of the medial stabilizers with subluxation of the patella. In these cases, the repair/reconstruction of medial stabilizers should follow the treatment of the chondral injury. Medial patellofemoral ligament reconstruction may be a more reliable method of stabilizing the patella than its repair, which has limitations related to the medial patellofemoral ligament injury location. Nowadays, there is no evidence available where osseous abnormalities should be addressed in addition to restoring the medial patellofemoral ligament.     

Antibiotic-loaded bone cement reduces risk of infections in primary total knee arthroplasty? A systematic review

Purpose

Antibiotic-loaded bone cement has been widely used for the treatment of infected knee replacement, but its routine use in primary TKA remains controversial. The aim of this systematic review was to analyze the literature about the antimicrobial efficacy and safety of antibiotic-loaded bone cement for its prophylactic use in primary TKA.

Methods

A detailed and systematic search of the Pubmed, Medline, Cochrane Reviews and Google Scholar databases had been performed using the keyword “total knee arthroplasty” “total knee replacement” “total knee prosthesis” and “antibiotic-loaded bone cement” with no limit regarding the year of publication. We used modified Coleman scoring methodology (mCMS) to identify scientifically sound articles in a reproducible format. The review was limited to the English-language articles.

Results

Six articles met inclusion criteria. In total, 6318 arthroplasties were included in our study. 3217 of these arthroplasties received antibiotic-loaded bone cement and 3101 arthroplasties served as the control. There was no statistical difference between the two groups in terms of the incidence of deep or superficial surgical site infection. The average mCMS score was 67.6, indicating good methodological quality in the included studies.

Conclusions

Present review did not reveal any significant difference in terms of rate of deep or superficial surgical site infection in patients receiving antibiotic-loaded bone cement compared with the control (plain bone cement) during primary TKA. The clinical relevance of this study was that the use of antibiotic-loaded bone cement did not significantly reduce the risk of infection in primary TKA.

Level of evidence

III.

     

New local anesthetics. Are they worth the cost?

Epidural analgesia that uses dilute concentrations of bupivacaine with fentanyl or sufentanil provides excellent analgesia, good sensory-motor discrimination, and minimal toxicity and is inexpensive. The new local anesthetic agents, ropivacaine and levobupivacaine, offer potential improvements in the risk of toxicity when administered in large doses but probably no important clinical difference when used in dilute concentrations for labor analgesia. After accounting for the potency difference, ropivacaine offers little or no motor-sparing advantage over bupivacaine. Currently, epidural anesthesia with concentrated bupivacaine is rarely used for cesarean section, so there is little indication for the newer anesthetic agents in this setting either. The authors believe that large difference in cost cannot be justified on the basis of currently available data.     

Knee flexion after total knee arthroplasty reduces blood loss

Purpose

Extensive blood loss after total knee arthroplasty (TKA) may be a potential problem since it leads to anaemia, increased need for transfusion and prolonged hospitalization. Aim of this study was to investigate the effects of postoperative knee flexion after TKA on blood loss and the need for transfusion.

Methods

One hundred consecutive patients undergoing primary TKA from 2012 to 2013 were randomizely divided into two groups. In one group, the knee was extended for the first 6 h after surgery, whereas in the other was flexed at 90° for the same time. Two doses of endovenous tranexamic acid were administered in all subjects. Patients were homogeneous for all the possible confounding factors.

Results

Calculated blood loss was 846 ± 197 (ml) in the flexion group and 1,242 ± 228 (ml) in the extension group (p < 0.05). Drop of haemoglobin levels at 24 h in the study group and the control group was 1.9 ± 0.8 (g/dl) and 3.0 ± 0.5 (g/dl), respectively (p < 0.01). Drop of haematocrit at 24 h was 4.5 ± 0.2 (%) in the flexion group and 6.7 ± 0.3 (%) in the extension group (p < 0.05). Blood transfusion was necessary in 5 patients in the control group and was not necessary in any patient of the study group. Average knee flexion at day 7 was 105° ± 4° in the flexion group and 98° ± 7° in the extension group.

Conclusion

Knee flexion at 90° after TKA, associated with the intraoperative use of tranexamic, acid is an effective method to reduce blood loss and the need for blood transfusion. The routine use of the present protocol is effective in reducing social costs and length of hospitalization of TKA procedures.

Level of evidence

Prospective comparative study, Level I.     

Prosthetic knee infection by resistant bacteria: the worst-case scenario

Purpose

The aim of the present paper was to determine (1) the incidence of failure (defined as the persistence or the recurrence of the infection), (2) the incidence of prosthesis (or even limb) loss (defined as the final need for an arthrodesis, resection arthroplasty or amputation) and (3) what factors could influence the failure in patients treated with a two-stage reimplantation for periprosthetic knee infections caused by resistant bacteria.

Methods

The authors retrospectively reviewed 29 total knee arthroplasties infected by resistant bacteria in 29 patients who underwent a two-stage revision. Between the stages, intravenous-targeted antibiotics were administered for a median period of 8 (range 6–12) weeks. Median follow-up was 10 (range 7–14) years.

Results

The authors found that failure occurred in 5 of 29 patients (17.2 %). When methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative staphylococci (MR-CoNS) were involved, failure rate was 10 % (2 of 20). When vancomycin-resistant enterococcus (VRE), multidrug-resistant (MDR) Acinetobacter baumannii and MDR Pseudomonas aeruginosa were involved, the failure rate was 33.3 % (3 of 9). Of those five patients, two underwent amputations, one chronic suppressive antibiotic therapy, one arthrodesis and one resection arthroplasty; among them, three lost the limb (10.3 % of the overall group). Timing of reimplantation and patient comorbidities did not significantly influence the failure.

Conclusions

Two-stage protocol resulted in a viable option for patients with infections by some resistant organisms (MRSA and MR-CoNS). However, when highly resistant organisms were involved (VRE, MDR Acinetobacter Baumannii and MDR Pseudomonas aeruginosa), the failure rate was much higher. In all cases of failure of the two-stage reimplantation, prosthesis (or even limb) loss occurred. Consequently, patients should be counselled that when highly resistant bacteria are involved, two-stage reimplantation could not be successful, with high final risk of prosthesis (or even limb) loss.

Level of evidence

Retrospective case series, Level IV.