Hyungsun Lim

Cartoon distraction alleviates anxiety in children during induction of anesthesia.

BACKGROUND:We performed this study to determine the beneficial effects of viewing an animated cartoon and playing with a favorite toy on preoperative anxiety in children aged 3 to 7 years in the operating room before anesthesia induction. METHODS:One hundred thirty children aged 3 to 7 years with ASA physical status I or II were enrolled. Subjects were randomly assigned to 1 of 3 groups: group 1 (control), group 2 (toy), and group 3 (animated cartoon). The children in group 2 were asked to bring their favorite toy and were allowed to play with it until anesthesia induction. The children in group 3 watched their selected animated cartoon until anesthesia induction. Children’s preoperative anxiety was determined by the modified Yale Preoperative Anxiety Scale (mYPAS) and parent-recorded anxiety Visual Analog Scale (VAS) the night before surgery, in the preanesthetic holding room, and just before anesthesia induction. RESULTS:In the preanesthetic holding room, the group 2 mYPAS and parent-recorded anxiety VAS scores were significantly lower than those of groups 1 and 3 (mYPAS: P = 0.007; parent-recorded anxiety VAS: P = 0.02). In the operating room, the children in group 3 had the lowest mYPAS and parent-recorded anxiety VAS scores among the 3 groups (mYPAS: P < 0.001; parent-recorded anxiety VAS: P < 0.001). In group 3, the mYPAS and parent-recorded anxiety VAS scores of only 3 and 5 children were increased in the operating room compared with their scores in the preanesthetic holding room, whereas the anxiety scores of 32 and 34 children in group 1 and 25 and 32 children in group 2 had increased (P < 0.001). The number of children whose scores indicated no anxiety (mYPAS score <30) in the operating room was 3 (7%), 9 (23%), and 18 (43%) in groups 1, 2, and 3, respectively (P < 0.001). CONCLUSIONS:Allowing the viewing of animated cartoons by pediatric surgical patients is a very effective method to alleviate preoperative anxiety. Our study suggests that this intervention is an inexpensive, easy to administer, and comprehensive method for anxiety reduction in the pediatric surgical population.

Anatomical Variations of the Origin of the Segment 4 Hepatic Artery and Their Clinical Implications

The threat of ischemic complications following massive resection, especially in living donor hepatectomy or split liver transplantation, has been haunting surgeons for many years. Postmortem dissections of 62 livers were performed to investigate anatomical variations of the principal artery for segment 4 (A4). The origin of A4 was examined separately in the liver with (n = 46) or without (n = 16) an aberrant left hepatic artery (abLHA). A4s were found to be extrahepatic or intrahepatic branches of the right hepatic artery (RHA), left hepatic artery, or proper hepatic artery and were categorized into 4 different types according to their origins. The RHA type, originating from the RHA or right anterior hepatic artery (RAHA), was the most common pattern in our series. The A4 roots had a strong tendency of stemming from the RHA (n = 12) even in the livers with abLHA (n = 16). Among the RHA‐type A4s, the A4 arising from RAHA (n = 2) is supposed to be the most dangerous variant because it can cause an ischemic change in the remaining part of the liver after right hepatectomy. In conclusion, in the era of living donor liver transplantation, paying particular attention to the point of origin of A4 is a prerequisite, especially when the lateral section is relatively small. Arterial injuries to A4 during split liver transplantation may also increase the risk of hepatic artery thrombosis and ischemic cholangiopathy. Liver Transpl 14:1180–1184, 2008.

Tracheal rupture after endotracheal intubation: A report of three cases

Tracheal rupture is a rare but serious complication that occurs after endotracheal intubation. It usually presents as a linear lesion in the membranous wall of the trachea, and is more prevalent in women and patients older than 50 years. The clinical manifestations of tracheal injury include subcutaneous emphysema and respiratory distress. We report the cases of three female patients of old age presenting tracheal rupture after endotracheal intubation. Two cases received surgical repair without complication and one recovered uneventfully after conservative management. We presume that the tracheal injuries were caused by over-inflation of cuff and sudden movement of the tube by positional change. Therefore, we recommend cuff pressure monitoring during general anesthesia and minimized movement of the head and neck at positional change.

Optimal nasopharyngeal temperature probe placement.

BACKGROUND:Although the nasopharynx is a commonly used temperature-monitoring site during general anesthesia, it is unknown whether the position of nasopharyngeal temperature probes placed blindly by anesthesia practitioners is optimal. The purposes of this study were (1) to determine where the nasopharyngeal mucosa is in closest proximity to the internal carotid artery (ICA) and (2) to evaluate the tip position of nasopharyngeal temperature probes that were placed by anesthesiology residents and nurse anesthetists. METHODS:In the first phase of the study, we reviewed enhanced axial computed tomography images of 100 patients to determine where the nasopharyngeal mucosa was in closest proximity to the left or the right ICA. The distance from this point to the nares was then measured in the sagittal image. In the second phase of the study, nasendoscopy was used to evaluate the positioning of nasopharyngeal temperature probes placed by anesthesiology residents (244 patients) or nurse anesthetists (116 patients). Malpositioned probes were repositioned to an optimal location, and the temperature differences were recorded. RESULTS:In the computed tomography images, the mucosa in closest proximity to the ICA was in the upper, mid-, and lower nasopharynx in 60%, 38%, and 2% of patients, respectively. The average distances between the ICA and the nasopharyngeal mucosa in the upper portion were significantly shorter than those in the lower portion (female: 9.4 vs 16.8 mm, P < 0.001; male: 12.4 vs 18.8 mm, P < 0.001). The average distances (95% prediction interval) from the nares to the upper portion of the nasopharynx through the inferior meatus were 9.1 (8.1–10.2) cm in females and 9.7 (8.6–10.8) cm in males. Temperature probes were correctly positioned in the upper or mid-nasopharynx by residents and nurses in 43% (95% confidence interval [CI], 37%–49%) and 41% (95% CI, 36%–50%), respectively. When the probe was inadvertently placed in the nasal cavity, the median (95% CI) temperature difference from the upper nasopharynx was 0.2°C (0.15°C–0.25°C). CONCLUSIONS:The closest portion of the nasopharyngeal mucosa to the ICA is within the upper or mid-nasopharynx. The depth from the nares to the upper one-third of the nasopharynx is approximately 10 cm. Less than half of nasopharyngeal temperature probes placed blindly by practitioners were optimally positioned.

Effects of intraoperative single bolus fentanyl administration and remifentanil infusion on postoperative nausea and vomiting.

Background Although the use of postoperative opioids is a well-known risk factor for postoperative nausea and vomiting (PONV), few studies have been performed on the effects of intraoperative opioids on PONV. We examined the effects of a single bolus administration of fentanyl during anesthesia induction and the intraoperative infusion of remifentanil on PONV. Methods Two hundred and fifty women, aged 20 to 65 years and scheduled for thyroidectomy, were allocated to a control group (Group C), a single bolus administration of fentanyl 2 µg/kg during anesthesia induction (Group F), or 2 ng/ ml of effect-site concentration-controlled intraoperative infusion of remifentanil (Group R) groups. Anesthesia was maintained with sevoflurane and 50% N2O. The incidence and severity of PONV and use of rescue antiemetics were recorded at 2, 6, and 24 h postoperatively. Results Group F showed higher incidences of nausea (60/82, 73% vs. 38/77, 49%; P = 0.008), vomiting (40/82, 49% vs. 23/77 30%; P = 0.041) and the use of rescue antiemetics (47/82, 57% vs. 29/77, 38%; P = 0.044) compared with Group C at postoperative 24 h. However, there were no significant differences in the incidence of PONV between Groups C and R. The overall incidences of PONV for postoperative 24 h were 49%, 73%, and 59% in Groups C, F, and R, respectively (P = 0.008). Conclusions A single bolus administration of fentanyl 2 µg/kg during anesthesia induction increases the incidence of PONV, but intraoperative remifentanil infusion with 2 ng/ml effect-site concentration did not affect the incidence of PONV.

The changes of endotracheal tube cuff pressure by the position changes from supine to prone and the flexion and extension of head

Background The proper cuff pressure is important to prevent complications related to the endotracheal tube (ETT). We evaluated the change in ETT cuff pressure by changing the position from supine to prone without head movement. Methods Fifty-five patients were enrolled and scheduled for lumbar spine surgery. Neutral angle, which was the angle on the mandibular angle between the neck midline and mandibular inferior border, was measured. The initial neutral pressure of the ETT cuff was measured, and the cuff pressure was subsequently adjusted to 26 cmH2O. Flexed or extended angles and cuff pressure were measured in both supine and prone positions, when the patients head was flexed or extended. Initial neutral pressure in prone was compared with adjusted neutral pressure (26 cmH2O) in supine. Flexed and extended pressure were compared with adjusted neutral pressure in supine or prone, respectively. Results There were no differences between supine and prone position for neutral, flexed, and extended angles. The initial neutral pressure increased after changing position from supine to prone (26.0 vs. 31.5 ± 5.9 cmH2O, P < 0.001). Flexed and extended pressure in supine were increased to 38.7 ± 6.7 (P < 0.001) and 26.7 ± 4.7 cmH2O (not statistically significant) than the adjusted neutral pressure. Flexed and extended pressure in prone were increased to 40.5 ± 8.8 (P < 0.001) and 29.9 ± 8.7 cmH2O (P = 0.002) than the adjusted neutral pressure. Conclusions The position change from supine to prone without head movement can cause a change in ETT cuff pressure.

Effect of ketorolac on the prevention of emergence agitation in children after sevoflurane anesthesia.

Background The purpose of this study was to evaluate the effects of ketorolac on the incidence and severity of emergence agitation in children recovering from sevoflurane anesthesia. Methods Eighty-five children aged 3 to 7 years were randomly assigned to the control group or the ketorolac group (1 mg/kg ketorolac). The children were evaluated by the Pediatric Anesthesia Emergence Delirium Scale and a four-point agitation scale. Results The median agitation scores did not differ significantly between the two groups. The overall incidence of emergence agitation was similar in the two groups (41% in the control group vs. 32% in the ketorolac group, P = 0.526). The number of children who received rescue drugs for treatment of emergence agitation was not significantly different between the two groups. Conclusions The administration of 1 mg/kg of ketorolac is not effective in decreasing the incidence and severity of emergence agitation in children aged 3 to 7 years after sevoflurane anesthesia.

Reliability of assessment of nasal flow rate for nostril selection during nasotracheal intubation

STUDY OBJECTIVE To evaluate the reliability of assessments of nasal flow rate for improved nostril selection for nasotracheal intubation. DESIGN Prospective, randomized, double-blinded study. SETTING Operating room of a university-affiliated hospital. PATIENTS 118 ASA physical status 1 and 2 patients, aged 18-65 years, scheduled for elective maxillofacial and oral surgery requiring nasotracheal intubation. INTERVENTIONS Patients were randomized to the left or right nostril groups. Forced vital capacity (FVC) and forced expiratory volume in one second (FEV(1)) through the mouth and each nostril were measured before anesthesia induction. MEASUREMENTS The relationship between the rate of airflow through the selected nostril and frequency of epistaxis and navigability of the nasotracheal tube were evaluated. MAIN RESULTS There were no significant differences in the frequency of epistaxis and degree of navigability of the tracheal tube between the left and right nostril groups. In both nostril groups, patients who suffered epistaxis showed significantly less FEV(1) and FEV(1)/FVC values than did patients without epistaxis (P < 0.05). In addition, in both groups patients who passed the tube easily showed significantly higher FEV(1) and FEV(1)/FVC values than did patients who passed the tube with resistance or failed tube passage (P < 0.05). CONCLUSION Measurement of nasal flow rate is a useful clinical method for choosing a nostril for nasotracheal intubation.

The effects of incremental continuous positive airway pressure on arterial oxygenation and pulmonary shunt during one-lung ventilation

Background Although one lung ventilation (OLV) is frequently used for facilitating thoracic surgical procedures, arterial hypoxemia can occur while using one lung anesthesia. Continuous positive airway pressure (CPAP) in 5 or 10 cmH2O to the non-ventilating lung is commonly recommended to prevent hypoxemia. We evaluated the effects of incremental CPAP to the non-ventilating lung on arterial oxygenation and pulmonary shunt without obstruction of the surgical field during OLV. Methods Twenty patients that were scheduled for one lung anesthesia were included in this study. Systemic and pulmonary hemodynamic data and blood gas analysis was recorded every fifteen minutes according to the patients positions and CPAP levels. CPAP was applied from 0 cmH2O by 3 cmH2O increments until a surgeon notifies that the surgical field was obstructed by the expanded lung. Following that, pulmonary shunt fraction (QS/QT) was calculated. Results There were no significant differences of QS/QT between supine and lateral positions with two lung ventilation (TLV). OLV significantly decreased arterial oxygen partial pressure (PaO2) and increased QS/QT compared to TLV. PaO2 and QS/QT significantly improved at 6 and 9 cmH2O of CPAP compared to 0 cmH2O. However, there were no significant differences of PaO2 and QS/QT between 6 and 9 cmH2O CPAP. In 18 patients (90%), surgical fields were obstructed at 9 cmH2O CPAP. Conclusions This study suggests that 6 cmH2O CPAP effectively improved arterial oxygenation without interference of the surgical field during OLV when CPAP was applied from 0 cmH2O in 3 cmH2O increments.

Measurements of the Length and Diameter of Main Bronchi on Three-Dimensional Images in Asian Adult Patients in Comparison With the Height of Patients

OBJECTIVE To measure the length and diameter of the main bronchus using the three-dimensional reconstruction images from the spiral chest computerized tomography scans in Asian adult patients, and to evaluate the relationship between the height of patients and the length and diameter of main bronchi. DESIGN Prospective observational study. SETTING Academic, tertiary care hospital. PARTICIPANTS Two hundred Asian adults undergoing a chest spiral computerized tomography scan. INTERVENTION No intervention. MEASUREMENTS AND MAIN RESULTS The authors measured the anteroposterior and transverse diameters of the mid-portion of the right main bronchus and 2 cm below the carina of the left main bronchus. In addition, the length of both main bronchi was also measured. The length of the left main bronchus was about 3-4 times greater than its right counterpart. The main bronchus of women was oval-shape, with a large anteroposterior diameter, but the main bronchus of men was round-shape. There was no significant correlation between the measurements of main bronchi and the height of patients. CONCLUSIONS The results showed that there is no direct relationship between the length and diameter of main bronchi and the height of patients. The height is not the criterion for choosing DLT size. Therefore, the authors proposed that 3-D images be used to determine the size of the main bronchi. The diameter of main bronchus using the 3-D images can be used to determine the optimal size of the DLT in a clinical setting, although further studies are needed.