Predictive Ability of Perfusion Index for Determining the Success of Adductor Canal Nerve Block for Postoperative Analgesia in Patients Undergoing Unilateral Total Knee Arthroplasty.

BACKGROUND: The perfusion index (PI) is an objective method used to determine a successful nerve block. This study aimed to investigate the prognostic ability of the PI for a successful adductor canal nerve block (ACB) and suggest the optimal PI cut-off value for predicting a block. METHODS: This study was a prospective observational study and enrolled a total of 39 patients. The patients were dichotomized into successful and inappropriate ACB groups according to the results of the sensation tests. The PI value, Pleth variability index (PVi) value, and heart rate were recorded one minute before the block, at the time of the block, and one to 30 min after the block at one-minute intervals. Delta (dPI), which was defined as the difference in PI value from the baseline (the value one minute before the block), was the primary outcome. The area under the receiver operating characteristic curve (AUROC) was calculated to determine the dPI prognostic accuracy and optimal cut-off value. RESULTS: Successful ACB was achieved in 33 patients, while ACB was inappropriate in six patients. The dPI showed significant differences between the two groups under the time interval measured (p = 0.001). The dPI at 5 and 20 min showed good prognostic ability for a successful block, with optimal cut-off values of 0.33 (AUROC: 0.725, 95% CI 0.499-0.951) and 0.64 (AUROC: 0.813, 95% CI 0.599-1.000), respectively. CONCLUSIONS: The dPI is an effective predictor of successful ACB. The suggested dPI cut-off values at 5 and 20 min were below 0.33 and 0.64, respectively.

Effects of Dexmedetomidine on Diaphragm Activity Measured by Ultrasonography in Spontaneously Breathing Patients.

Background: Diaphragm movement is well correlated with inspired volume of the lung. Dexmedetomidine (DEX) has less effect on respiratory functions than other sedatives. The objective of this study was to investigate diaphragmatic movement using ultrasound (US) during DEX infusion for sedation in spontaneously breathing patients undergoing unilateral upper limb surgery. Methods: A total of 33 consecutive patients were enrolled in this study. Patients were sedated using DEX with ipsilateral axillary brachial nerve plexus block. Diaphragmatic activity was evaluated using diaphragmatic thickening at end-inspiration (TEI), diaphragmatic thickening at end-expiration (TEE), and diaphragmatic thickening fraction (DTF) measured by diaphragmatic US at three time-points; T0, baseline; T1, after DEX sedation; and T2, after DEX recovery. Supplementary oxygen was applied with a simple mask at 5 L/min. Peripheral oxygen saturation (SpO2), end tidal CO2 (EtCO2), and respiratory rate (RR) were recorded. Results: TEI and TEE showed no significant changes during the study period (P = 0.394 and P = 0.205, respectively). DTF was maintained at both T0 and T1 (P = 1.000). At recovery after DEX infusion discontinued, DTF was increased by 3.85%, although such increase was not statistically significant (T0 vs. T2, P = 0.525). SpO2 remained above 99% and EtCO2 remained below 36 mmHg. Desaturation episodes were not observed during the study period. Conclusions: Results of this study showed that DEX sedation did not affect the diaphragmatic movement in situation of decreased RR induced by DEX. This finding implies that DEX-induced sedation does not result in clinically significant respiratory depression.

Risk factors affecting the difficulty of fiberoptic nasotracheal intubation.

BACKGROUND: The success rate of intubation under direct laryngoscopy is greatly influenced by laryngoscopic grade using the Cormack-Lehane classification. However, it is not known whether grade under direct laryngoscopy can also affects the success rate of nasotracheal intubation using a fiberoptic bronchoscpe, so this study investigated the same. In addition, we investigated other factors that influence the success rate of fiberoptic nasotracheal intubation (FNI). METHODS: FNI was performed by 18 anesthesiology residents under general anesthesia in patients over 15 years of age who underwent elective oral and maxillofacial operations. In all patients, the Mallampati grade was measured. Laryngeal view grade under direct laryngoscopy, and the degree of secretion and bleeding in the oral cavity was measured and divided into 3 grades. The time required for successful FNI was measured. If the intubation time was > 5 minutes, it was evaluated as a failure and the airway was managed by another method. The failure rate was evaluated using appropriate statistical method. Receiver operating characteristic (ROC) curves and area under the curve (AUC) were also measured. RESULTS: A total of 650 patients were included in the study, and the failure rate of FNI was 4.5%. The patient's sex, age, height, weight, Mallampati, and laryngoscopic view grade did not affect the success rate of FNI (P > 0.05). BMI, the number of FNI performed by residents (P = 0.03), secretion (P < 0.001), and bleeding (P < 0.001) grades influenced the success rate. The AUCs of bleeding and secretion were 0.864 and 0.798, respectively, but the AUC of BMI, the number of FNI performed by residents, Mallampati, and laryngoscopic view grade were 0.527, 0.616, 0.614, and 0.544, respectively. CONCLUSION: Unlike in intubation under direct laryngoscopy, in the case of FNI, oral secretion and nasal bleeding had a significant effect on FNI difficulty than Mallampati grade or Laryngeal view grade.

A novel technique of submandibular intubation with a camera cable drape: a case report.

Submental or submandibular intubation has been reported to cause fewer complications than tracheostomy. However, the risk of infection is always inherent because oral wounds are exposed to microbial flora and bacteria in the oral cavity. A novel technique of submandibular intubation was devised to reduce infection and injury to the soft tissues. We would like to report a novel safe technique that can be performed in patients requiring submental or submandibular intubation. This is the first report of submandibular intubation using a sterile disposable camera cable drape. This novel technique of submandibular intubation is safer, more sterile, easier, and less invasive than conventional submandibular intubation.

Comparison between total intravenous anesthesia and balanced anesthesia on postoperative opioid consumption in patients who underwent laparoscopic-assisted distal gastrectomy.

Remifentanil is the most frequently prescribed opioid for total intravenous anesthesia (TIVA) or balanced anesthesia (BA), due to its favorable pharmacological properties. However, several studies have reported opioid-induced hyperalgesia and/or acute tolerance after intraoperatively using remifentanil. In addition, it is imperative to control postoperative pain with lower doses of opioid anesthetic agents. Therefore, we compared the amount of opioid consumption between TIVA with propofol-remifentanil and BA with desflurane-remifentanil, to control postoperative pain in patients who underwent laparoscopic-assisted distal gastrectomy (LADG) with gastroduodenostomy.We retrospectively evaluated demographic variables (age, gender, height, weight, and smoking habits), the duration of general anesthesia (GA), and intraoperatively administered remifentanil consumption through the electronic medical records of patients who underwent LADG with gastroduodenostomy due to early stomach cancer. The primary outcome was postoperative opioid consumption during postoperative day (POD) 2. The secondary outcomes were the incidence of any rescue opioid analgesics administered, numeric rating scale, and various adverse effects during POD 2. We categorized the data in 2 patient groups to compare TIVA with propofol-remifentanil (TIVA group) to BA with desflurane-remifentanil (BA group) on the postoperative opioid analgesic consumption.We divided 114 patients into the TIVA (46 patients) and BA (68 patients) groups. Opioid consumption as a primary outcome was significantly higher in the BA group than in the TIVA group during POD 2 except in the post-anesthesia care unit. The cumulative opioid consumption was significantly higher in the BA than in the TIVA group. The incidence of rescue analgesic at POD 2 was higher in the BA than in the TIVA group. In the TIVA group, remifentanil consumption was higher, and the duration of GA was shorter than that in the BA group. No statistically significant differences were observed when comparing other variables.Our results indicated that the maintenance of GA with TIVA (propofol-remifentanil) reduces opioid consumption for postoperative pain control compared to BA (desflurane-remifentanil) in patients undergoing LADG with gastroduodenostomy.

Effects on postoperative nausea and vomiting of nefopam versus fentanyl following bimaxillary orthognathic surgery: a prospective double-blind randomized controlled trial.

BACKGROUND: Postoperative nausea and vomiting (PONV) frequently occurs following bimaxillary orthognathic surgeries. Compared to opioids, Nefopam is associated with lower incidences of PONV, and does not induce gastrointestinal tract injury, coagulopathy, nephrotoxicity, or fracture healing dysfunction, which are common side effects of Nonsteroidal anti-inflammatory drugs. We compared nefopam- and fentanyl-induced incidence of PONV in patients with access to patient-controlled analgesia (PCA) following bimaxillary orthognathic surgeries. METHODS: Patients undergoing bimaxillary orthognathic surgeries were randomly divided into nefopam and fentanyl groups. Nefopam 120 mg or fentanyl 700 µg was mixed with normal saline to a final volume of 120 mL. Patients were given access to nefopam or fentanyl via PCA. Postoperative pain intensity and PONV were measured at 30 minutes and 1 hour after surgery in the recovery room and at 8, 24, 48, and 72 hours after surgery in the ward. The frequency of bolus delivery was compared at each time point. RESULTS: Eighty-nine patients were enrolled in this study, with 48 in the nefopam (N) group and 41 in the fentanyl (F) group. PONV occurred in 13 patients (27.7%) in the N group and 7 patients (17.1%) in the F group at 8 hours post-surgery (P = 0.568), and there were no significant differences between the two groups at any of the time points. VAS scores were 4.4 ± 2.0 and 3.7 ± 1.9 in the N and F groups, respectively, at 8 hours after surgery (P = 0.122), and cumulative bolus delivery was 10.7 ± 13.7 and 8.6 ± 8.5, respectively (P = 0.408). There were no significant differences in pain or bolus delivery at any of the remaining time points. CONCLUSION: Patients who underwent bimaxillary orthognathic surgery and were given nefopam via PCA did not experience a lower rate of PONV compared to those that received fentanyl via PCA. Furthermore, nefopam and fentanyl did not provide significantly different postoperative pain control.

Airway management in pediatric tongue flap division for oronasal fistula closure: A case report.

Oronasal fistulae (ONF) could remain after surgery in some patients with cleft palate. ONF ultimately requires intraoral surgery, which may lead to perioperative airway obstruction. Tongue flap surgery is a technique used to repair ONF. During the second surgery for performing tongue flap division, the flap transplanted from the tongue dorsum to the palate of the patient acts as an obstacle to airway management, which poses a great challenge for anesthesiologists. In particular, anesthesiologists may face difficulty in airway evaluation and patient cooperation during general anesthesia for tongue flap division surgery in pediatric patients. The authors report a case of airway management using a flexible fiberoptic bronchoscope during general anesthesia for tongue flap division surgery in a 6-year-old child.

Analysis of the effect of oral midazolam and triazolam premedication before general anesthesia in patients with disabilities with difficulty in cooperation.

BACKGROUND: When performing dental treatment under general anesthesia in adult patients who have difficulty cooperating due to intellectual disabilities, anesthesia induction may be difficult as well. In particular, patients who refuse to come into the dental office or sit in the dental chair may have to be forced to do so. However, for adult patients with a large physique, physical restraint may be difficult, while oral sedatives as premedication may be helpful. Here, a retrospective analysis was performed to investigate the effect of oral sedatives. METHODS: A hospital-based medical information database was searched for patients who were prescribed oral midazolam or triazolam between January 2009 and December 2017. Pre-anesthesia evaluation, anesthesia, and anesthesia recovery records of all patients were analyzed, and information on disability type, reason for prescribing oral sedatives, prescribed medication and dose, cooperation level during anesthesia induction, anesthesia duration, length of recovery room stay, and complications was retrieved. RESULTS: A total of 97 patients were identified, of whom 50 and 47 received midazolam and triazolam, respectively. The major types of disability were intellectual disabilities, autism, Down syndrome, blindness, cerebral palsy, and epilepsy. Analyses of changes in cooperation levels after drug administration showed that anesthesia induction without physical restraint was possible in 56.0% of patients in the midazolam group and in 46.8% of patients in the triazolam group (P = 0.312). CONCLUSIONS: With administration of oral midazolam or triazolam, general anesthesia induction without any physical restraint was possible in approximately 50% of patients, with no difference between the drugs.

Orotracheal intubation in a patient with difficult airway by using fiberoptic nasotracheal intubation: A case report.

In cases of a difficult intubation where numerous intubation methods, including laryngoscopy, have failed, yet oral intubation is still necessary, the method of tube exchange after fiberoptic nasal intubation may be attempted. Fiberoptic nasal intubation allows intubation to be performed relatively easily when the laryngeal view grade is poor. We report a case in which our attempt at oral intubation for total maxillectomy with laryngoscopy and fiberoptic oral intubation had failed due to an unexpected difficult airway; subsequently, we successfully completed the surgery by performing fiberoptic nasal intubation to secure the airway, followed by using a tube exchanger to exchange to an oral endotracheal tube.

Efficacy of Adjuvant 10% Hypertonic Saline in Transforaminal Epidural Steroid Injection: A Retrospective Analysis.

BACKGROUND: Chronic lower back pain with or without radiculopathy represents an important medical, social, and economic problem. Many treatment modalities and techniques, including surgery and epidural administration of steroids, have been used to manage this pain. Hypertonic saline, which has been used as an adjunct to percutaneous epidural adhesiolysis, can also be injected via a transforaminal approach in expectation of longer-lasting effects. OBJECTIVES: This study aimed to determine the effect of adding hypertonic saline to conventional transforaminal epidural steroid injections (TFEI) to provide pain relief for chronic radiculopathy patients. STUDY DESIGN: A retrospective study. SETTING: Pain clinic of a university hospital. METHODS: Between January 2010 and December 2013, the medical records of 246 patients (94 in the hypertonic group, 153 in the control group) who received transforaminal epidural block were reviewed and analyzed. The hypertonic group received 10% sodium chloride solution added to lidocaine, triamcinolone, and hyaluronidase. Outcomes on pain reduction were measured using a numerical rating scale (NRS) and the responder rate at baseline, one, 3, and 6 months after procedure. RESULTS: The estimated difference in NRS scores from baseline throughout a 6-month follow-up period in the hypertonic group were significantly higher (P = 0.0003). The proportion of substantial responders (41.9% vs. 34.6% at one month, 40.9% vs. 26.8% at 3 months, and 33.3% vs. 14.4% at 6 months, respectively, P = 0.0058) and substantial/moderate responders (71.0% vs. 58.8% at one month, 65.6% vs. 40.4% at 3 months, and 48.4% vs. 20.3% at 6 months, respectively, P < 0.0001) were significantly higher in the hypertonic group. The Oswestry disability index (ODI) was not different between the groups (P = 0.2697). LIMITATIONS: Retrospective design without a control group. CONCLUSIONS: Hypertonic saline provides more superior and longer lasting pain relieving effects when added to TFEIs.Key words: Back pain, epidural injections, epidural steroids, hypertonic saline, lumbar, radiculopathy, transforaminal.

Optimal Angle of Contralateral Oblique View in Cervical Interlaminar Epidural Injection Depending on the Needle Tip Position.

BACKGROUND: Chronic neck and upper extremity pain associated with cervical origin is common, and cervical interlaminar epidural steroid injections (CILESIs) are frequently used to manage the symptoms of cervical spinal disorders. However, CILESIs are associated with risks such as dural puncture and cord injury. OBJECTIVES: We aimed to determine the optimal needle tip visualization, in order to minimize CILESIs-induced complications. STUDY DESIGN: Retrospective observational study. SETTING: The single center study in Seoul, Republic of Korea. METHODS: Participants were 312 adults with neck or upper extremity pain caused by cervical lesion such as cervical herniated nucleus pulposus (HNPs). They underwent magnetic resonance imaging (MRI). Patients with severe cervical spinal stenosis, prior posterior cervical spine surgery, or other anatomical abnormalities of the vertebral laminae were excluded from the study. By using axial T2-weighted spin-echo MRI, we defined the area between the spinous processes as the anterior posterior zone 1 (APZ1), and the area lateral to the spinous processes as the anterior posterior zone 2 (APZ2). Line 1 was drawn along the ventral margin of lamina that confined APZ1, and line 2 was similarly drawn in order to define APZ2. The angles between the midsagittal line and lines 1 and 2 were defined as angle 1 and angle 2, respectively. Angles were measured at the C5-6, C6-7, and C7-T1 levels, on both right and left sides at each level. RESULTS: Angle 1 values (in degrees) at right C5-6, left C5-6, right C6-7, left C6-7, right C7-T1, and left C7-T1 were 62.54 ± 10.52, 64.34 ± 9.86, 62.03 ± 10.27, 62.87 ± 10.64, 61.64 ± 11.0, and 62.58 ± 10.83, respectively. Angle 2 values at right C5-6, left C5-6, right C6-7, left C6-7, right C7-T1, and left C7-T1 were 50.44 ± 6.84, 50.77 ± 7.00, 49.15 ± 6.07, 49.89 ± 6.45, 50.84 ± 6.68, and 50.24 ± 6.60, respectively. There were significant differences between angles 1 and 2 at each level. LIMITATIONS: This study is a retrospective review and did not employ controls, blinding, or randomization. Additionally, the optimal CLO angles for CILESIs and cervicothoracic interlaminar epidural steroid injections (CTILESIs) have not been assessed in clinical studies. Another limitation is that we divided lamina into only APZ1 and APZ2. CONCLUSIONS: During CILESIs, a contralateral oblique (CLO) view at 60 degrees is superior to other angles for visualizing the epidural space when the needle tip is placed in the interlaminar space and within the spinous processes margin. When the needle tip is placed in the interlaminar space and lateral to the spinous processes, a CLO view at 50 degrees is most appropriate.Institutional Review Board (IRB) approval number: S2016-0390-0001Key words: Chronic neck pain, chronic upper extremity pain, cervical epidural injections, cervical interlaminar steroid injections, steroid, needle tip position, needle tip visualization, fluoroscopy, complication, contralateral oblique view.

Predictors of the Treatment Response of Spontaneous Intracranial Hypotension to an Epidural Blood Patch.

Spontaneous intracranial hypotension (SIH) is characterized by postural headache because of low cerebrospinal fluid (CSF) pressure. Brain magnetic resonance imaging (MRI) and radioisotope (RI) cisternography can be used to identify the site of a CSF leakage. Although autologous epidural blood patch (EBP) is a very effective treatment modality, some patients require a repeat autologous EBP. We investigated whether autologous EBP responses correlate with surrogate markers of quantitative findings.All cases of autologous EBP for SIH from January 2006 to December 2014 were enrolled. The demographic variables, number of EBPs, pain scores, RI cisternography (early visualization of bladder activity), and MRI findings (subdural fluid collections, pachymeningeal enhancement, engorgement of venous structures, pituitary hyperemia, and sagging of the brain) were reviewed.Patients with early bladder activity on RI cisternography had a tendency to need a higher number of autologous EBPs. Only sagging of the brain and no other variables showed a statistically significant negative correlation with the number of autologous EBPs.The response to autologous EBP may be related to the radiologic findings of early bladder activity on RI cisternography and sagging of the brain on MRI.

Predictive value of rotational thromboelastometry during cardiopulmonary bypass for thrombocytopenia and hypofibrinogenemia after weaning of cardiopulmonary bypass.

BACKGROUND: The early detection of coagulopathy helps guide decisions regarding optimal transfusion management during cardiac surgery. This study aimed to determine whether rotational thromboelastometry (ROTEM) analysis during cardiopulmonary bypass (CPB) could predict thrombocytopenia and hypofibrinogenemia after CPB. METHODS: We analyzed 138 cardiac surgical patients for whom ROTEM tests and conventional laboratory tests were performed simultaneously both during and after CPB. An extrinsically activated ROTEM test (EXTEM), a fibrin-specific ROTEM test (FIBTEM) and PLTEM calculated by subtracting FIBTEM from EXTEM were evaluated. Correlations between clot amplitude at 10 min (A10), maximal clot firmness, platelet count, and fibrinogen concentrations at each time point were calculated. A receiver operating characteristic analysis with area under the curve (AUC) was used to assess the thresholds of EXTEM, PLTEM and FIBTEM parameters during CPB and for predicting thrombocytopenia and hypofibrinogenemia after weaning of CPB. RESULTS: The A10 on EXTEM, PLTEM, and FIBTEM during CPB showed a good correlation with platelet counts (r = 0.622 on EXTEM and r = 0.637 on PLTEM; P < 0.0001 for each value) and fibrinogen levels (r = 0.780; P < 0.0001) after CPB. A10 on a FIBTEM threshold of 8 mm during the CPB predicted a fibrinogen concentration < 150 mg/dl (AUC = 0.853) after CPB. Additionally, the threshold level of A10 on EXTEM during CPB for predicting platelet counts < 100,000 /µl after CPB was 42 mm (AUC = 0.768). CONCLUSIONS: EXTEM, PLTEM, and FIBTEM parameters during CPB may be useful for predicting thrombocytopenia and hypofibrinogenemia after weaning of CPB.

The decellularized vascular allograft as an experimental platform for developing a biocompatible small-diameter graft conduit in a rat surgical model.

PURPOSE: The present study was aimed to assess the feasibility of using decellularized aortic allograft in a rat small animal surgical model for conducting small diameter vascular tissue engineering research. MATERIALS AND METHODS: Decellularized aortic allografts were infra-renally implanted in 12 Sprague-Dawley (SD) adult rats. The conduits were harvested at 2 (n = 6) and 8 weeks (n = 6), and assessed by hematoxylin and eosin (H&E), van Gieson, Masson Trichrome staining, and immunohistochemistry for von Willebrand factor, CD 31(+), and actin. RESULTS: Consistent, predictable, and reproducible results were produced by means of a standardized surgical procedure. All animals survived without major complications. Inflammatory immune reaction was minimal, and there was no evidence of aneurysmal degeneration or rupture of the decellularized vascular implants. However, the aortic wall appeared thinner and the elastic fibers in the medial layer showed decreased undulation compared to the normal aorta. There was also minimal cellular repopulation of the vascular media. The remodeling appeared progressive from 2 to 8 weeks with increased intimal thickening and accumulation of both collagen and cells staining for actin. Although the endothelial like cells appeared largely confluent at 8 weeks, they were not as concentrated in appearance as in the normal aorta. CONCLUSION: The results showed the present rat animal model using decellularized vascular allograft implants to be a potentially durable and effective experimental platform for conducting further research on small diameter vascular tissue engineering.