Identifying the ideal tracheostomy site based on patient characteristics during percutaneous dilatational tracheostomy without bronchoscopy / 대한마취과학회지

BACKGROUND@#We previously reported that percutaneous dilatational tracheostomy (PDT) can be safely performed 2 cm below the cricothyroid membrane without the aid of a bronchoscope. Although our simplified method is convenient and does not require sophisticated equipment, the precise location for tracheostomy cannot be confirmed. Because it is recommended that tracheostomy be performed at the second tracheal ring, we assessed whether patient characteristics could predict the distance between the cricothyroid membrane and the second tracheal ring.@*METHODS@#Data from 490 patients who underwent three-dimensional neck computed tomography from January 2012 to December 2015 were analyzed, and the linear distance from the upper part of the cricoid cartilage (CC) to the lower part of the second tracheal ring (2TR) was measured in the sagittal plane.@*RESULTS@#The mean CC-to-2TR distance was 25.26 mm (95% CI 25.02–25.48 mm). Linear regression analysis showed that the predicted CC-to-2TR distance could be calculated as −5.73 + 0.2 × height (cm) + 1.22 × sex (male: 1, female: 0) + 0.01 × age (yr) −0.03 × weight (kg) (adj. R² = 0.55).@*CONCLUSIONS@#These results suggest that height and sex should be considered when performing PDT without bronchoscope guidance.

Identifying the ideal tracheostomy site based on patient characteristics during percutaneous dilatational tracheostomy without bronchoscopy / 대한마취과학회지

BACKGROUND: We previously reported that percutaneous dilatational tracheostomy (PDT) can be safely performed 2 cm below the cricothyroid membrane without the aid of a bronchoscope. Although our simplified method is convenient and does not require sophisticated equipment, the precise location for tracheostomy cannot be confirmed. Because it is recommended that tracheostomy be performed at the second tracheal ring, we assessed whether patient characteristics could predict the distance between the cricothyroid membrane and the second tracheal ring. METHODS: Data from 490 patients who underwent three-dimensional neck computed tomography from January 2012 to December 2015 were analyzed, and the linear distance from the upper part of the cricoid cartilage (CC) to the lower part of the second tracheal ring (2TR) was measured in the sagittal plane. RESULTS: The mean CC-to-2TR distance was 25.26 mm (95% CI 25.02–25.48 mm). Linear regression analysis showed that the predicted CC-to-2TR distance could be calculated as −5.73 + 0.2 × height (cm) + 1.22 × sex (male: 1, female: 0) + 0.01 × age (yr) −0.03 × weight (kg) (adj. R² = 0.55). CONCLUSIONS: These results suggest that height and sex should be considered when performing PDT without bronchoscope guidance.

Postoperative pain control by ultrasound guided brachial plexus block reduces emergence delirium in pediatric patients

BACKGROUND: Pediatric patients awakening from general anesthesia may experience emergence delirium (ED), often due to inadequate pain control. Nerve block completely inhibits innervation of the surgical site and is superior to systemic analgesics. This study assessed whether pain control through nerve block relieves ED after general anesthesia. METHODS: Fifty patients aged 2–7 years with humerus condyle fractures were randomly assigned to receive ultrasound guided supraclavicular brachial plexus block (BPB group) or intravenous fentanyl (Opioid group). The primary outcome was score on the pediatric anesthesia emergence delirium (PAED) scale on arrival at the postanesthesia care unit (PACU). Secondary outcomes were severity of agitation and pain in the PACU, the incidence of ED, and postoperative administration of rescue analgesics over 24 h. RESULTS: PAED scale was significantly lower in the BPB group at arrival in the PACU (7.2 ± 4.9 vs. 11.6 ± 3.2; mean difference [95% confidence interval (CI)] = 4.4 [2.0–6.8], P < 0.001) and at all other time points. The rate of ED was significantly lower in the BPB group (36% vs. 72%; relative risk [95% CI] = 0.438 [0.219–0.876], P = 0.023). The BPB group also had significantly lower pain scores and requiring rescue analgesics than Opioid group in the PACU. CONCLUSIONS: Ultrasound guided BPB, which is a good option for postoperative acute phase pain control, also contributes to reducing the severity and incidence of ED.

Effect of an epinephrine mixture for interscalene block on hemodynamic changes after the beach chair position under general anesthesia: a retrospective study / 대한마취과학회지

BACKGROUND: The beach chair position (BCP) can cause significant hypotension. Epinephrine is used to prolong the duration of local anesthetics; it is also absorbed into blood and can exert systemic effects. This study determined the effects of epinephrine mixed with ropivacaine for an interscalene block (ISB) on hemodynamic changes related to BCP. METHODS: Patient data collected from March 2013 to August 2014 were used retrospectively. We divided the patients into three groups: 1) ISB only, 2) I+G (general anesthesia after ISB without epinephrine), and 3) I+E+G (general anesthesia after ISB with epinephrine). Mean blood pressure (MBP) and heart rate (HR) were measured for 30 minutes at 5-minute intervals. RESULTS: The study analyzed data from 431 patients. MBP tended to decrease gradually in the groups I+G and I+E+G. There were significant differences in MBP between the groups I+G and I, and between the groups I+G and I+E+G. Group I+E+G showed a significant increase in HR compared with the other two groups. CONCLUSIONS: ISB with an epinephrine mixture did not prevent hypotension caused by the BCP after general anesthesia. HR increased only in response to the epinephrine mixture. A well-planned prospective study is required to compare hemodynamic changes in that context.

Effect of dexmedetomidine on endotracheal intubating conditions during endotracheal intubation without neuromuscular blocker following propofol/remifentanil

BACKGROUND: In the present study, we investigated the effect of dexmedetomidine on the intubating conditions and hemodynamic changes during endotracheal intubation following anesthetic induction performed using propofol and remifentanil without a neuromuscular blocking agent. METHODS: We selected 70 adult patients aged 20 to 65 years scheduled to undergo general anesthesia. Induction was performed using 2 mg/kg of propofol and 1.5 µg/kg of remifentanil. The patients were divided into two groups, a dexmedetomidine group (Group D) and a control group (Group C). Group D received an infusion of dexmedetomidine 1 µg/kg for 10 minutes before induction, and Group C received the same volume of normal saline infused in the same manner. Intubating conditions were evaluated and blood pressure and heart rate were recorded at various time points to assess hemodynamic stability. RESULTS: Intubating conditions were evaluated as excellent for 34 patients and good for 1 patient in Group D, and excellent for 4 patients, good for 20 patients, poor for 4 patients, and bad for 7 patients in Group C (P < 0.001). The heart rate was significantly lower in Group D than in Group C at all measurement times. The mean arterial blood pressure was significantly lower in Group C than in Group D at 10 minutes after dexmedetomidine administration (P = 0.049), after the induction of anesthesia (P < 0.001), immediately after endotracheal intubation (P = 0.008), and 3 minutes after endotracheal intubation (P < 0.001). CONCLUSIONS: Dexmedetomidine 1 µg/kg improved the intubating conditions and stabilized hemodynamic changes following anesthetic induction performed using propofol 2 mg/kg and remifentanil 1.5 µg/kg without a neuromuscular blocking agent.

Facilitation of AMPA receptor-mediated steady-state current by extrasynaptic NMDA receptors in supraoptic magnocellular neurosecretory cells

In addition to classical synaptic transmission, information is transmitted between cells via the activation of extrasynaptic receptors that generate persistent tonic current in the brain. While growing evidence supports the presence of tonic NMDA current (INMDA) generated by extrasynaptic NMDA receptors (eNMDARs), the functional significance of tonic I(NMDA) in various brain regions remains poorly understood. Here, we demonstrate that activation of eNMDARs that generate I(NMDA) facilitates the α-amino-3-hydroxy-5-methylisoxazole-4-proprionate receptor (AMPAR)-mediated steady-state current in supraoptic nucleus (SON) magnocellular neurosecretory cells (MNCs). In low-Mg2+ artificial cerebrospinal fluid (aCSF), glutamate induced an inward shift in I(holding) (I(GLU)) at a holding potential (V(holding)) of -70 mV which was partly blocked by an AMPAR antagonist, NBQX. NBQX-sensitive I(GLU) was observed even in normal aCSF at V(holding) of -40 mV or -20 mV. I(GLU) was completely abolished by pretreatment with an NMDAR blocker, AP5, under all tested conditions. AMPA induced a reproducible inward shift in I(holding) (I(AMPA)) in SON MNCs. Pretreatment with AP5 attenuated I(AMPA) amplitudes to ~60% of the control levels in low-Mg2+ aCSF, but not in normal aCSF at V(holding) of -70 mV. I(AMPA) attenuation by AP5 was also prominent in normal aCSF at depolarized holding potentials. Memantine, an eNMDAR blocker, mimicked the AP5-induced I(AMPA) attenuation in SON MNCs. Finally, chronic dehydration did not affect I(AMPA) attenuation by AP5 in the neurons. These results suggest that tonic I(NMDA), mediated by eNMDAR, facilitates AMPAR function, changing the postsynaptic response to its agonists in normal and osmotically challenged SON MNCs.

Efficacy of the oral neurokinin-1 receptor antagonist aprepitant administered with ondansetron for the prevention of postoperative nausea and vomiting / 대한마취과학회지

BACKGROUND: 5-HT3 receptor antagonist, dexamethasone and droperidol were used for the prevention of postoperative nausea and vomiting (PONV). Recently, neurokinin-1 (NK1) antagonist has been used for PONV. We evaluated the effect of oral aprepitant premedication in addition to ondansetron. METHODS: A total 90 patients scheduled for elective rhinolaryngological surgery were allocated to three groups (Control, Ap80, Ap125), each of 30 at random. Ondansetron 4 mg was injected intravenously to all patients just before the end of surgery. On the morning of surgery, 80 mg and 125 mg aprepitant were additionally administered into the Ap80 group and Ap125 group, respectively. The rhodes index of nausea, vomiting and retching (RINVR) was checked at 6 hr and 24 hr after surgery. RESULTS: Twelve patients who used steroids unexpectedly were excluded. Finally 78 patients (control : Ap80 : Ap125 = 24 : 28 : 26) were enrolled. Overall PONV occurrence rate of Ap125 group (1/26, 3.9%) was lower (P = 0.015) than the control group (7/24, 29.2%) at 6 hr after surgery. The nausea distress score of Ap125 group (0.04 +/- 0.20) was lower (P = 0.032) than the control group (0.67 +/- 1.24) at 6 hr after surgery. No evident side effect of aprepitant was observed. CONCLUSIONS: Oral aprepitant 125 mg can be used as combination therapy for the prevention of PONV.

The difference in the dose of vasoactive drugs and rocuronium according to the general anesthesia method during open gastrectomy

BACKGROUND: Recently, balanced anesthesia (BA: halogenated volatile anesthetics + remifentanil) has been useful for abdominal surgery. The authors therefore performed a retrospective study about the difference in the dose of vasoactive drugs and rocuronium according to the general anesthesia type. METHODS: BA was compared with inhalational anesthesia (IA: halogenated volatile anesthetics + N2O) and total intravenous anesthesia (TIVA: propofol + remifentanil). The records of a total of 415 patients (IA : TIVA : BA = 126 : 157 : 132) who received open gastrectomy between 2004 to 2010 were analyzed. The types of vasoactive drugs and dosage as well as infusion time were calculated. The total amounts of vasoactive drugs were scored by two different methods. Infusion drugs were scored as 30 points, whereas bolus drugs were scored as 5 points. Drug score is the total sum of each score, where each drug score point split either into Plus or Minus. Plus means raising the blood pressure whereas Minus means the opposite. For rocuronium dosage, a total of 286 patients (IA : TIVA : BA = 89 : 78 : 119) who met the criteria were enrolled, and this formula was used (total rocuronium/weight/time, microg/kg/hr). RESULTS: The BA group showed a lower (P = 0.01) Minus score (1.8 +/- 4.0) compared to the IA group (3.6 +/- 5.2). Less amount of rocuronium (P = 0.001) was administered in the BA (327 +/- 72 microg/kg/hr), compared to the IA (368 +/- 93 microg/kg/hr) and TIVA (356 +/- 81 microg/kg/hr). CONCLUSIONS: BA seems to require less hypotensive agent and rocuronium compared with IA and TIVA for open gastrectomy. But, well-designed prospective studies are required.

Spinal anesthesia for emergency cesarean section in a preeclampsia patient diagnosed with type 1 neurofibromatosis / 대한마취과학회지

No abstract available.

Obstruction of the endotracheal tube due to cyanoacrylate leakage in a pediatric recurrent tracheoesophageal fistula patient: A case report

A 6-year old female, who was operated on for tracheoesophageal fistula at the time of birth, was diagnosed with recurrent TEF, and it was decided to undergo endoscopic management, using cyanoacrylate under general anesthesia. After cuffing, the endotracheal tube was located at the level of the fistula, and endoscopic management was undertaken through the esophagus, using cyanoacrylate. The peak inspiratory pressure was shown to have increased from 18 to 28 cmH2O. We observed partial obstruction of the endotracheal tube end, and partial attachment of the cyanoacrylate to the tracheal wall. The patient's symptoms gradually improved, and no other particular finding was observed during the following two months. We suppose that the cyanoacrylate has been ventilated, and gradually excreted. In manipulation that may cause changes in the tube position, it is recommended to check ventilation via the fistula, and to recheck the tube position.

The relationship of preoperative N-terminal pro-BNP and the amount of hemodynamic drugs used during noncardiac surgery

BACKGROUND: BNP and NT-proBNP are very useful predictor of perioperative cardiac events. The authors therefore performed a retrospective study about the relationship between NT-proBNP and intraoperative hemodynamic stability. METHODS: The authors reviewed the chart of 126 patients which were consulted to cardiologists for preoperative cardiac evaluation from 2005 through 2007. All patients were divided into two groups; N-group (NT-proBNP or = 300 pg/ml, n = 60). The kinds of hemodynamic drugs and dosage and infusion time were calculated. Total amounts of hemodynamic drugs are scored by two methods. Infusion drugs were scored 30 points, bolus drugs (esmolol 30 mg, labetalol 10 mg, phenylephrine 50microg, ephedrine 10 mg, atropine 0.25 mg, nicardipine 0.5 mg) and preclusive nitroglycerin infusion were scored 5 points. Drug score is total sum of all scores. We compared the drug score of two groups. In addition, bivariate and partial correlation analysis were performed for the correlation of drug score. RESULTS: H-group showed a high (P = 0.029) drug score (17.68 +/- 21.78) more than N-group (10.13 +/- 15.79). H-group showed a low (P = 0.000) ejection fraction (51.69 +/- 12.90%) more than N-group (61.80 +/- 7.84%). But, only age (R: 0.234, P: 0.023) and ejection fraction (R: -0.222, P: 0.032) were correlated with drug score by partial correlation analysis. CONCLUSIONS: Patients with preoperative high NT-proBNP had decreased systolic function and demanded more hemodynamic drugs during noncardiac surgery. But, NT-proBNP was not correlated with drug score in itself.

A comparative study on the usefulness of the Glidescope or Macintosh laryngoscope when intubating normal airways / 대한마취과학회지

BACKGROUND: The Glidescope Videolaryngoscope (GVL) is a newly developed video laryngoscope. It offers a significantly improved laryngeal view and facilitates endotracheal intubation in difficult airways, but it is controversial in that it offers an improved laryngeal view in normal airways as well. And the price of GVL is expensive. We hypothesized that intubation carried out by fully experienced anesthesiologists using the GVL with appropriate pre-anesthetic preparations offers an improved laryngeal view and shortened intubation time in normal airways. Therefore, the aim of this study was to compare the GVL with the Macintosh laryngoscope in normal airways and to determine whether GVL can substitute the Macintosh laryngoscope. METHODS: This study included 60 patients with an ASA physical status of class 1 or 2 requiring tracheal intubation for elective surgery. All patients were randomly allocated into two groups, GVL (group G) or Macintosh (group M). ADS (airway difficulty score) was recorded before induction of anesthesia. The anesthesiologist scored vocal cord visualization using the percentage of glottic opening (POGO) visible and the subjective ease of intubation on a visual analogue scale (VAS). The time required to intubate was recorded by an assistant. RESULTS: There was a significant increase in POGO when using the GVL (P < 0.05). However, there was no difference in the time required for a successful tracheal intubation using the GVL compared with the Macintosh laryngoscope. The VAS score on the ease of intubation was significantly lower for the GVL than for the Macintosh laryngoscope (P < 0.05). CONCLUSIONS: GVL could be a first-line tool in normal airways.

Comparison of the Effects of Propofol and Ketamine on Respiratory Mechanics during Anesthetic Induction in Children / 대한마취과학회지

BACKGROUND: Propofol and ketamine are believed to reduce airway resistance. The aim of the present study was to compare the effect of propofol and ketamine on respiratory mechanics after endotracheal intubation in children. METHODS: Forty pediatric patients were assigned randomly to two groups: propofol (n = 20) and ketamine (n = 20). Patients were anesthetized with propofol (2 mg/kg) or ketamine (2 mg/kg). All patients were paralyzed with rocuronium (0.8 mg/kg) and intubated and ventilated mechanically (ETCO2: 30-40 mmHg, tidal volume: 10 ml/kg, respiratory rate: 15-25 time/min). Peak inspiratory pressure (PIP), respiratory resistance (Rr), dynamic compliance (Cdyn) and expiratory tidal volume (Vte) measurements were recorded at five time points; 0.5 min after intubation without sevoflurane (baseline), following 2.5 min, 5 min, 7.5 min and 10 min of ventilation with 2% sevoflurane- 50% nitrous oxide. RESULTS: Rr at 0.5 min after intubation was 27.4 +/- 12.7 cmH2O/L/s in the propofol group, and 30.0 +/- 13.5 cmH2O/L/s in the ketamine group. Cdyn at 0.5 min after intubation was 28.0 +/- 9.9 ml/cmH2O in the propofol group, and 25.1 +/- 10.6 ml/cmH2O in the ketamine group. There was no significant difference in the response of PIP, Rr, Cdyn and Vte between two groups and within groups. CONCLUSIONS: We suggest that the effects of propofol and ketamine on respiratory mechanics were similar during anesthetic induction in children.

The Effects of Remifentanil Pretreatment on Rocuronium Injection Pain and Cardiovascular Response during Anesthetic Induction / 대한마취과학회지

BACKGROUND: Remifentanil is an opioid agonist with rapid onset and ultra-short duration of action. Rocuronium bromide can elicit a high incidence of pain when intravenous injection. In this study, the quantitative effect of remifentanil pretreatment on the injection pain of rocuronium and cardiovascular response during anesthetic induction were evaluated. METHODS: Eighty adult female patients undergoing gynecological procedures with general anesthesia were analyzed for this study. Patients were randomly allocated to one of four groups. Patients received 2 ml of normal saline (n = 20), 2 ml (40 mg) of 2% lidocaine (n = 20), 2 ml of remifentanil 0.5 microgram/kg (n = 20) or 2 ml of remifentanil 1 microgram/kg (n = 20) 60 seconds prior to administration of rocuronium 0.7 mg/kg. Pain was assessed after rocuronium injection. Systolic and diastolic arterial blood pressure and heart rates were measured before and during anesthetic induction. RESULTS: Both remifentanil and lidocaine have the good effect in minimizing the rocuronium injection pain. But, only 1 microgram/kg of remifentanil blunts the hypertension after endotracheal intubation. CONCLUSIONS: A bolus dose (1 microgram/kg) of remifentanil may be used for minimizing the rocuronium injection pain and blunting the hypertension after endotracheal intubation.