Pro and Con: How Important Is the Exact Location of Adductor Canal and Femoral Triangle Blocks?

In this Pro-Con commentary article, we debate the importance of anterior thigh block locations for analgesia following total knee arthroplasty. The debate is based on the current literature, our understanding of the relevant anatomy, and a clinical perspective. We review the anatomy of the different fascial compartments, the course of different nerves with respect to the fascia, and the anatomy of the nerve supply to the knee joint. The Pro side of the debate supports the view that more distal block locations in the anterior thigh increase the risk of excluding the medial and intermediate cutaneous nerves of the thigh and the nerve to the vastus medialis, while increasing the risk of spread to the popliteal fossa, making distal femoral triangle block the preferred location. The Con side of the debate adopts the view that while the exact location of local anesthetic injection appears anatomically important, it has not been proven to be clinically relevant.

Astaxanthin Attenuates D-Galactosamine-Induced Pancreatic Injury by Activating Antioxidant Enzymes and Inhibiting VEGF-C Gene Expression.

<b>Background and Objective:</b> Astaxanthin (3,3'-dihydroxy-ß-ß-carotene-4,4'-dione) is a carotenoid, commonly found in marine environments has been reported to possess versatile biological properties including anti-inflammatory and antioxidant. In this study, the pancreatic protective effect of astaxanthin was investigated in D-Galactosamine-induced pancreas injury in rats. <b>Materials and Methods:</b> In this experimental study, MTT assay was used to determine cytotoxic effects of the Astaxanthin on pnc1 cells. A total of 30 adult albino rats divided into 5 groups, six rats in each. Group I was given an equal amount of distilled water, group II was received 400 mg kg¹ b.wt. D-galactosamine on 15th day, groups III-V were treated with astaxanthin (50 and 100 mg kg¹) and/or silymarin (50 mg kg¹) for 14 days + 400 mg kg¹ b.wt. D-galactosamine on the 15th day, respectively. <b>Results:</b> IC₅₀of Astaxanthin against the pnc1 cell line was 92.9 µg mL¹. The daily oral administration of astaxanthin (50 and 100 mg kg¹) as well as silymarin (50 mg kg¹) for 14 days to rats treated with D-galactosamine resulted in a significant improvement in plasma AST, ALT, ALP as well as pancreatic TNF-α, IL-1ß, IL-10, NO and VEGF-C gene expression. On the other hand, inducible oral administration of astaxanthin increased the activity of pancreatic GSH, SOD, GPx, GR, CAT and the level of TBARs in D-galactosamine-treated pancreatic of rats. Furthermore, Astaxanthin almost normalized these effects in pancreatic tissue histoarchitecture and MRI examination. <b>Conclusion:</b> The obtained results showed that Astaxanthin protected experimental animals against D-galactosamine-induced pancreatic injury through activation of antioxidant enzymes and IL-10 and inhibition of VEGF-C activation.

A One-Year Institutional View of Resident Physician Burnout.

OBJECTIVES: This prospective study explores the prevalence, associated characteristics, and trajectory of burnout over one academic year in a multidisciplinary sample of resident physicians using a relatively new burnout survey instrument. METHODS: All residents from a U.S. academic health center (n = 633) were invited to complete the Copenhagen Burnout Inventory (CBI) three times, with 4-month time lags between invitations. A total of 281 (44%) provided complete CBI survey responses at least once, and 43 (7%) did at all three times. Descriptive statistics, cross-sectional analyses, correlations, and multivariable linear regression analyses were computed, as well as repeated measures ANOVAs and paired t tests, as appropriate, for each CBI domain (personal, work, patient-related burnout). RESULTS: About half had CBI scores indicating moderate-to-high levels of personal burnout (49-52%) and work-related burnout (45-49%), whereas patient-related burnout was less common (14-24%). However, patient-related burnout increased significantly from the beginning to the end of the year. Regression analyses indicated patient-related burnout was significantly higher for postgraduate year 1-2 residents compared to PGY 4+ residents, but was not significantly different by gender. Personal and work burnout scores were significantly higher for females. Persistently high burnout was observed in only 6% of respondents. CONCLUSIONS: In this study of resident physicians using the CBI, burnout was prevalent and higher levels of burnout were observed for females on the personal and work burnout domains, while junior residents had higher patient-related burnout. Persistently, high burnout was rare. The CBI demonstrated high reliability, was practical to administer, and produced similar results with existing burnout research.

Morphine versus fentanyl patient-controlled analgesia for postoperative pain control in major hepatic resection surgeries including living liver donors: A retrospective study.

BACKGROUND: Liver resection surgery results in significant postoperative pain. However, it is still not clear which opioids used by patient-controlled analgesia (PCA) provides the best pain control and results in the least side effect in a patient with impaired liver function. Our hypothesis was that fentanyl is a better choice than morphine as it is a potent analgesic that its elimination half-life does not depend on the hepatic uptake and metabolism. THE STUDY PURPOSE: Is to compare morphine and fentanyl PCA in liver resection patients as regards the degree of pain control, the consumption of opioids, and the side effects. METHODS: A retrospective case-control study of hepatic resection patients who received postoperative morphine (Morph) or fentanyl (Fent) PCA. The study compared the pain scores, the morphine equivalent dose (MED), the number of demands requested as recorded by the PCA infusion pump, and the side effects every 12 h for 48 h. RESULTS: This study yielded 40 patients; with the majority were living donor hepatic resection patients. There was no significant difference in the pain scores. However, the MED and the demands were significantly less in the Morph group. The P < 0.000, 0.0001, 0.0005, and 0.003, demands P < 0.002, 0.006, 0.014, and 0.013 at 12, 24, 48, and 36 h, respectively. The overall side effects were not different between the 2 groups at all time intervals measured; however, Morph patients were significantly more sedated in the first 12 h. There was one case of respiratory depression in the Morph group compared to two cases in the in the Fent group that needed treatment with naloxone. CONCLUSIONS: Although both groups had adequate pain control. The Morphine group reached faster pain control with less MED and PCA requests in liver resection patients, although it was more sedating in the first 12 h. However, fentanyl patients were less sedated; both drugs need close monitoring in the immediate postoperative period due to reported respiratory depressive effect and the need to use naloxone. The dosage of the PCA settings needs to be studied further to reach to the best dose with a reduced side effect. Further studies are recommended to reduce PCA dosages by introducing a multimodal approach of pain management relying on other methods with no additional sedative effects as regional anterior abdominal blocks.

Intraoperative Hypotension During Second Stage of Deep Brain Stimulator Placement: Same Day versus Different Day Procedures.

BACKGROUND: We evaluated blood pressure management associated with implantable pulse generator (IPG) procedure on same day (SD) versus different day (DD) from deep brain stimulation (DBS) placement. METHODS: A retrospective chart review of 99 records for vasopressors given during IPG using a negative binomial regression model was performed. An association between SD versus DD, cumulative vasopressor dose, and minimum and maximum mean arterial pressure (MAP) were sought. RESULTS: No significant association between SD versus DD DBS and the number of times vasopressors were given during stage II, estimated ratio of means (CI) of 1.8 (0.9-3.5); P = 0.07. Day of stage II had no association with the cumulative dose of vasopressor given during stage II, with an estimated difference in means (CI) of 2.4 (-0.4 to 5.3). The SD group had a significantly lower mean of minimum stage II MAP compared with DD, with an estimated difference in means (CI) of -10.5 (-17.4 to -3.5; P < 0.001). There was no association with maximum stage II MAP, with an estimated difference in means (CI) of -2.8 (-17.6 to 12.0; P = 0.63). CONCLUSION: No difference in intraoperative vasopressor use was found between SD versus DD IPG placement, but the SD group had a significantly lower minimum MAP.

Comparison of 2 resident learning tools-interactive screen-based simulated case scenarios versus problem-based learning discussions: a prospective quasi-crossover cohort study.

STUDY OBJECTIVE: Simulation-based learning is emerging as an alternative educational tool in this era of a relative shortfall of teaching anesthesiologists. The objective of the study is to assess whether screen-based (interactive computer simulated) case scenarios are more effective than problem-based learning discussions (PBLDs) in improving test scores 4 and 8 weeks after these interventions in anesthesia residents during their first neuroanesthesia rotation. DESIGN: Prospective, nonblinded quasi-crossover study. SETTING: Cleveland Clinic. PATIENTS: Anesthesiology residents. INTERVENTIONS: Two case scenarios were delivered from the Anesoft software as screen-based sessions, and parallel scripts were developed for 2 PBLDs. Each resident underwent both types of training sessions, starting with the PBLD session, and the 2 cases were alternated each month (ie, in 1 month, the screen-based intervention used case 1 and the PBLD used case 2, and vice versa for the next month). MEASUREMENTS: Test scores before the rotation (baseline), immediately after the rotation (4 weeks after the start of the rotation), and 8 weeks after the start of rotation were collected on each topic from each resident. The effect of training method on improvement in test scores was assessed using a linear mixed-effects model. MAIN RESULTS: Compared to the departmental standard of PBLD, the simulation method did not improve either the 4- or 8-week mean test scores (P = .41 and P = .40 for training method effect on 4- and 8-week scores, respectively). Resident satisfaction with the simulation module on a 5-point Likert scale showed subjective evidence of a positive impact on resident education. CONCLUSIONS: Screen-based simulators were not more effective than PBLD for education during the neuroanesthesia rotation in anesthesia residency.

Postoperative vision loss after spine surgery: a single-institution case-control comparison.

BACKGROUND: Postoperative vision loss (POVL) after spine surgery is a rare but devastating outcome. We present the first case-control study from a single institution for POVL with the diagnoses of ischemic optic neuropathy or central vision loss after complex spine surgery. METHODS: POVL cases following spine surgeries between December 1995 and December 2010 at the Cleveland Clinic were identified retrospectively using administrative codes. Each instance of POVL was matched to 5 case-control patients based on age, gender, body mass index, systolic blood pressure, diastolic blood pressure, mean arterial pressure, and hematocrit. Duration of anesthesia, fluid volumes, and hemodynamic measurements were then compared between POVL cases and control cases using Wilcoxon rank sum test. RESULTS: Six patients developed POVL. These patients had significantly greater blood loss (P=0.002, Wilcoxon test) and a significantly greater volume of red blood cells transfused (P=0.006) than the control patients. No other intraoperative measures differed significantly after Bonferroni correction for multiple outcomes. CONCLUSION: We found that patients with POVL had significantly greater blood loss and significantly more red blood cell transfusions than their matched controls.

Factors predicting incremental administration of antihypertensive boluses during deep brain stimulator placement for Parkinson's disease.

Hypertension is common in deep brain stimulator (DBS) placement predisposing to intracranial hemorrhage. This retrospective review evaluates factors predicting incremental antihypertensive use intraoperatively. Medical records of Parkinson's disease (PD) patients undergoing DBS procedure between 2008-2011 were reviewed after Institutional Review Board approval. Anesthesia medication, preoperative levodopa dose, age, preoperative use of antihypertensive medications, diabetes mellitus, anxiety, motor part of the Unified Parkinson's Disease Rating Scale score and PD duration were collected. Univariate and multivariate analysis was done between each patient characteristic and the number of antihypertensive boluses. From the 136 patients included 60 were hypertensive, of whom 32 were on angiotensin converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB), told to hold on the morning of surgery. Antihypertensive medications were given to 130 patients intraoperatively. Age (relative risk [RR] 1.01; 95% confidence interval [CI] 1.00-1.02; p=0.005), high Joint National Committee (JNC) class (p<0.0001), diabetes mellitus (RR 1.4; 95%CI 1.2-17; p<0.0001) and duration of PD >10 years (RR 1.2; 95%CI 1.1-1.3; p=0.001) were independent predictors for antihypertensive use. No difference was noted in the mean dose of levodopa (p=0.1) and levodopa equivalent dose (p=0.4) between the low (I/II) and high severity (III/IV) JNC groups. Addition of dexmedetomidine to propofol did not influence antihypertensive boluses required (p=0.38). Intraoperative hypertension during DBS surgery is associated with higher age group, hypertensive, diabetic patients and longer duration of PD. Withholding ACEI or ARB is an independent predictor of hypertension requiring more aggressive therapy. Levodopa withdrawal and choice of anesthetic agent is not associated with higher intraoperative antihypertensive medications.

Ultrasound-guided supraclavicular brachial plexus block: single versus triple injection technique for upper limb arteriovenous access surgery.

BACKGROUND: Although ultrasound-guided supraclavicular block has a good success rate, it remains unclear whether multiple injections are superior to single injection (SI). We compared the sensory block success rate of SI versus triple injection (TI). METHODS: In this randomized double-blind study, 96 end-stage renal disease patients undergoing arteriovenous fistula creation or superficialization were randomly allocated to receive either SI or TI. The primary outcome was the combined score of sensory blockade of the 5 nerves (median, ulnar, radial, medial cutaneous nerve of the forearm, and musculocutaneous) measured at 5, 10, 15, and 20 minutes after injection. Secondary outcome variables were the time to onset of the blockade, performance time (time to do the block), separate success rate for each of the above nerves, success rate of surgical anesthesia, and the complication rate. RESULTS: The combined success of the sensory block was 20% to 31% higher in the TI group than in the SI group at 10, 15, and 20 minutes after injection (all P < 0.035). The block of the musculocutaneous nerve in the TI group was faster and more successful than in the SI group, at all time points (all P < 0.026). The average time needed to perform the block was significantly longer in the TI than the SI group (6.5 ± 2.1 vs 4.7 ± 2.1 minutes, P = 0.001). The overall success of surgical anesthesia measured at 30 minutes did not differ significantly between the 2 groups (96% in TI vs 87% in SI, P = 0.253). CONCLUSIONS: Although the performance time of the SI technique was shorter, TI had a faster onset and resulted in a more successful block of all nerves in the first 20 minutes.

Some epidurographic explanations for incomplete epidural analgesia coverage in the absence of a catheter.

STUDY OBJECTIVE: To determine the impact of the plica mediana dorsalis (PMD) on injected contrast media spread in the epidural space. DESIGN: Prospective interventional study. SETTING: Academic medical center. PATIENTS: 30 chronic pain patients ranging in age from 37 to 71 years, undergoing epidural steroid injection. INTERVENTIONS AND MEASUREMENTS: Epidurograms were evaluated for the 1) presence or absence of a PMD and 2) bilateral differential density and the extent of contrast spread on either side of the midline, horizontally and vertically. RESULTS: The PMD (defined as midline radiolucency in epidurograms) was observed in (80%) 24/30 patients based on the epidurograms that were evaluated. Denser contrast spread on one side was found in (79%) 19/24 patients who had the PMD and in (33%) 2/6 patients who did not have the PMD (P = 0.03). Horizontal and vertical asymmetrical spread of the contrast was observed in (67%) 16 of 24 patients with the PMD and in (50%) 3 of 6 of patients without the PMD in each direction independently. CONCLUSION: The difference in density of contrast spread on either side of the midline carries important clinical implications in understanding the pathogenesis of inadequate epidural analgesia and/or unilateral excessive motor weakness or numbness.

Asleep-awake-asleep craniotomy: a comparison with general anesthesia for resection of supratentorial tumors.

The anesthetic plan for patients undergoing awake craniotomy, when compared to craniotomy under general anesthesia, is different, in that it requires changes in states of consciousness during the procedure. This retrospective review compares patients undergoing an asleep-awake-asleep technique for craniotomy (group AW: n = 101) to patients undergoing craniotomy under general anesthesia (group AS: n = 77). Episodes of desaturation (AW = 31% versus AS = 1%, p < 0.0001), although temporary, and hypercarbia (AW = 43.75 mmHg versus AS = 32.75 mmHg, p < 0.001) were more common in the AW group. The mean arterial pressure during application of head clamp pins and emergence was significantly lower in AW patients compared to AS patients (pinning 91.47 mmHg versus 102.9 mmHg, p < 0.05 and emergence 84.85 mmHg versus 105 mmHg, p < 0.05). Patients in the AW group required less vasopressors intraoperatively (AW = 43% versus AS = 69%, p < 0.01). Intraoperative fluids were comparable between the two groups. The post anesthesia care unit (PACU) administered significantly fewer intravenous opioids in the AW group. The length of stay in the PACU and hospital was comparable in both groups. Thus, asleep-awake-asleep craniotomies with propofol-dexmedetomidine infusion had less hemodynamic response to pinning and emergence, and less overall narcotic use compared to general anesthesia. Despite a higher incidence of temporary episodes of desaturation and hypoventilation, no adverse clinical consequences were seen.

Evaluation of "no touch" extubation technique on airway-related complications during emergence from general anesthesia.

BACKGROUND AND OBJECTIVES: Awake "no touch" extubation requires performing extubations only when the patient spontaneously wakes up without any kind of stimulation during emergence from general anesthesia. The aim of this study was to evaluate absolutely awake extubation "no touch" technique in adult patients, scheduled for elective nasal and paranasal sinus surgeries under general anesthesia as regard to emergence airway complications. METHODS: A total of 60 adult patients were randomly allocated into one of two equal groups according to the method of extubation: Group I: Standard fully awake, Group II: Absolutely "no touch" awake extubation (absolutely no stimulation no touch was allowed until patients were able to open their eyes). The incidence of laryngospasm and its grade according to a four-point scale was reported. Occurrence of airway events (excessive secretions, breath-holding, coughing, hoarseness, biting, as well as the number and severity of any desaturation episodes), oozing from the wound, and postoperative sore throat were also recorded. The heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressure measured at the end of surgery served as baseline values, and subsequent measurements were taken within 30 minutes after the end of surgery. RESULTS: There was absolutely no case of laryngeal spasm or episode of desaturation among patients who were extubated with the "no touch" technique. On the other hand, there were 3 cases of laryngeal spasm in standard fully awake group. Severity of coughing, excessive secretions and breath holding, hoarseness, biting, and occurrence of non-purposeful movements of the limbs were significantly less in the absolutely "no touch" technique awake technique. The changes in HR, SBP, and DBP during emergence extubation were significantly less in "no touch" technique technique group. However, oozing from the wound was significantly higher with standard fully awake extubation. However, there were no significant differences between the two groups regarding the incidence of postoperative sore throat (39 and 36%, respectively). CONCLUSION: The results of the present study showed that awake "no touch" technique technique for tracheal extubation produces less airway-related complications, as well as minimal hemodynamic response during emergence from general anesthesia in nasal and paranasal surgeries. It could be a safe alternative for tracheal extubation in airway surgery.