Tomoko Yorozu

Nasal intubation with Bullard laryngoscope : a useful approach for difficult airways

Since the original technique using the Bullard laryngoscope requires considerable practice to be reliable, we have developed an easier method with a directional-tip endotracheal tube through the nostril. We first examined the feasibility of our method in patients with or without difficult airways. All 26 patients with difficult airways were successfully tracheally intubated with our method, and times for visualization and intubation were not different from those in 10 patients with normal airways. We further examined the direction of the tips of endotracheal tubes through the nostril in 128 patients with normal airways using four combinations of two kinds of both laryngoscopes (Bullard and Macintosh) and endotracheal tubes (directional-tip tube: EndotrolTM Mallinckrodt Laboratories, Athlone, Ireland; or straight distal-end tube: Blue LineTM, Portex Ltd., Hythe Kent, United Kingdom). We found that a combination of the Bullard laryngoscope and the EndotrolTM tube had a higher probability of accessing the center of the glottis than the others. In conclusion, nasal insertion of a directional-tip tube assisted by the Bullard laryngoscope is an assured and prompt procedure for intubating the tracheas of patients with difficult airways.

Comparative effect of 6% hydroxyethyl starch (containing 1% dextrose) and lactated Ringer's solution for cesarean section under spinal anesthesia

AbstractPurpose. This study aimed to compare low-molecular weight hydroxyethyl starch containing 1% dextrose (HES) infusion and lactated Ringers solution (LR) in the prevention of hypotension associated with spinal anesthesia for cesarean section. Methods. Sixty-seven patients scheduled for cesarean section under spinal anesthesia were randomly allocated to receive either LR (n= 35) or HES (n= 32) infusion before cesarean delivery. Infusion of the fluid was started immediately after arrival at the operating room, through two fully open i.v. routes of 18 or 16 gauge. The two groups were compared in terms of the incidence of hypotension; ephedrine dose; cord and maternal blood gas, hemoglobin, and glucose; and Apgar scores. Results. Intravenous fluid volume until delivery in the LR group was significantly greater than that in the HES group (1298 ± 503 and 973 ± 339 ml, respectively) in spite of the similar periods of intravenous infusion (18.1 ± 3.9 and 18.2 ± 4.1 min). The incidence of hypotension, and the ephedrine dose, blood gas analyses, and Apgar scores were not significantly different between the groups. The ephedrine dose correlated with the anesthesia level by spinal anesthesia (P < 0.05). Conclusion. This study did not show an advantage of HES compared with LR in the prevention of hypotension or in the reduction of ephedrine dose during cesarean section under spinal anesthesia. The anesthesia level, rather than the choice of intravenous fluid solution, might be related to the ephedrine dose.

Recurrent ST-segment elevation on ECG and ventricular tachycardia during neurosurgical anesthesia

This article reports an unusual case of repeated intraoperative myocardial ischemia and ventricular arrhythmia during neurosurgical anesthesia. The presentation was clinically diagnosed as coronary spasm after successful resuscitation. Intraoperative prostaglandin E1 and β-adrenergic blockade, as well as vagal stimulation due to surgical manipulation, may have contributed to the episode.

Factors influencing intraoperative bradycardia in adult patients

PurposeIn order to elucidate the prominent factors involved in intraoperative bradycardia in adult patients, we retrospectively investigated the association between the potential risk factors and intraoperative bradycardia, using multiple logistic regression.MethodsThe perioperative records for 499 adult patients who had undergone any of six elective surgeries were retrospectively examined. The potential factors included patient characteristics, the use of perioperative drugs for anesthesia, and the types of operational procedures. Heart rates were extracted at five points perioperatively. The frequencies and total doses of atropine injections to treat bradycardia were examined. Simple and multiple logistic regressions were used to analyze the relative risk factors for a intraoperative bradycardia.ResultsThe multiple logistic regression analysis revealed that the absence of atropine premedication was the most prominent risk factor for bradycardia (odds ratio; 1.86–5.51) from arrival in the operating room until the end of the operation. Other prominent factors, whose effects were only temporary, were as follows. Males had a higher risk of bradycardia than females upon arrival in the operating room. Surgical procedures with an epidural or subarachnoid blockade tended to have a higher risk for bradycardia after the operation. Propofol induction had a greater risk for bradycardia than thiopental after the end of the operation. Endotracheal intubation had a lower risk for bradycardia than no endotracheal intubation after induction. Vecuronium tended to induce bradycardia after operation.ConclusionThe most prominent factor affecting heart rate was atropine premedication. It was noteworthy that a single preoperative administration of atropine affected heart rate throughout the operation.

Intrathecal Administration of Morphine Decreases Persistent Pain after Cesarean Section: A Prospective Observational Study

Purpose Chronic pain after cesarean section (CS) is a serious concern, as it can result in functional disability. We evaluated the prevalence of chronic pain after CS prospectively at a single institution in Japan. We also analyzed perioperative risk factors associated with chronic pain using logistic regression analyses with a backward-stepwise procedure. Materials and Methods Patients who underwent elective or emergency CS between May 2012 and May 2014 were recruited. Maternal demographics as well as details of surgery and anesthesia were recorded. An anesthesiologist visited the patients on postoperative day (POD) 1 and 2, and assessed their pain with the Prince Henry Pain Scale. To evaluate the prevalence of chronic pain, we contacted patients by sending a questionnaire 3 months post-CS. Results Among 225 patients who questionnaires, 69 (30.7%) of patients complained of persistent pain, although no patient required pain medication. Multivariate analyses identified lighter weight (p = 0.011) and non-intrathecal administration of morphine (p = 0.023) as determinant factors associated with persistent pain at 3 months. The adjusted odds ratio of intrathecal administration of morphine to reduce persistent pain was 0.424, suggesting that intrathecal administration of morphine could decrease chronic pain by 50%. In addition, 51.6% of patients had abnormal wound sensation, suggesting the development of neuropathic pain. Also, 6% of patients with abnormal wound sensation required medication, yet no patients with persistent pain required medication. Conclusion Although no effect on acute pain was observed, intrathecal administration of morphine significantly decreased chronic pain after CS.

Epidural anesthesia during upper abdominal surgery provides better postoperative analgesia

Since repeated noxious stimuli may sensitize neuropathic pain receptors of the spinal cord, we tested the hypothesis that the appropriate blockade of surgical stimuli with epidural anesthesia during upper abdominal surgery would be beneficial for postoperative analgesia. Thirty-six adult patients undergoing either elective gastrectomy or open cholecystectomy were randomly allocated to receive either inhalational general anesthesia alone (group G) or epidural anesthesia along with light general anesthesia (group E) throughout the surgery. Postoperative pain management consisted of patient-controlled analgesia (PCA) with bupivacaine accompanied by the continuous infusion of buprenorphine. To assess postoperative pain, a visual analogue scale (VAS) was employed at 2, 24, and 48 h postoperatively. While there was no significant difference in the bupivacaine dose, more patients undergoing gastrectomy in group G required supplemental analgesics than those in group E, and the VAS scores in group E demonstrated significantly better postoperative analgesia compared to group G after both types of surgery. Thus, an appropriate epidural blockade during upper abdominal surgery likely provides better postoperative pain relief.

Quadratus lumborum block for femoral-femoral bypass graft placement: A case report.

Introduction:Atherosclerosis has a complex etiology that leads to arterial obstruction and often results in inadequate perfusion of the distal limbs. Patients with atherosclerosis can have severe complications of this condition, with widespread systemic manifestations, and the operations undertaken are often challenging for anesthesiologists. Case report:A 79-year-old woman with chronic heart failure and respiratory dysfunction presented with bilateral gangrene of the distal lower extremities with obstruction of the left common iliac artery due to atherosclerosis. Femoral–femoral bypass graft and bilateral foot amputations were planned. Spinal anesthesia failed due to severe scoliosis and deformed vertebrae. General anesthesia was induced after performing multiple nerve blocks including quadratus lumborum, sciatic nerve, femoral nerve, lateral femoral cutaneous nerve, and obturator nerve blocks. However, general anesthesia was abandoned because of deterioration in systemic perfusion. The surgery was completed; the patient remained comfortable and awake without the need for further analgesics. Conclusion:Quadratus lumborum block may be a useful anesthetic technique to perform femoral–femoral bypass.

Difficult Airway Due to an Undiagnosed Subglottic Tumor: A Case Report.

AbstractThe “cannot ventilate, cannot intubate” scenario during anesthesia induction can be lethal. We present a patient with an undiagnosed subglottic tumor who developed the “cannot ventilate, cannot intubate” situation after induction of general anesthesia, due to the presence of an undiagnosed subglottic tumor.A 93-year-old woman was brought to the operating room for repair of a femoral neck fracture. Both ventilation and intubation could not be accomplished, and the patient was awakened without complications after trials of maintaining the airway. In order to reverse muscle relaxation, sugammadex was useful to allow resumption of spontaneous breathing.A difficult airway can be caused by an undiagnosed subglottic tumor. Subglottic tumors can be misdiagnosed as asthma, because the clinical presentation can be very similar. If cricothyrotomy had been performed based on airway management algorithms, the airway may not have been controlled with a possibly fatal outcome. Ultrasound examination of the trachea may be useful to diagnose obstructive lesions in the airway.

Noninvasive Positive Pressure Ventilation against Reperfusion Pulmonary Edema following Percutaneous Transluminal Pulmonary Angioplasty

A 69-year-old man with chronic thromboembolic pulmonary hypertension (CTEPH) was on amblatory oxygen inhalation therapy (3 L/min) and scheduled for percutaneous transluminal pulmonary angioplasty (PTPA). The patients New York Heart Association functional status was class III with recent worsening of dyspnea and apparent leg edema. Transthoracic echocardiography revealed right ventricular enlargement with mean pulmonary artery pressure of 42 mmHg. After PTPA, he was complicated with postoperative reperfusion pulmonary edema, and noninvasive positive pressure ventilation (NPPV) was applied immediately. Hypoxemia was successfully treated with 15 days of NPPV. Although mean pulmonary artery pressure was unchanged, his brain natriuretic peptide level decreased from preoperative 390.3 to postoperative 44.3 pg/dL. In addition, total pulmonary resistance decreased from preoperative 18 to postoperative 9.6 wood unit·m2. The patient was discharged on day 25 with SpO2 of 95% on 5 L/min of oxygen inhalation. Because pulmonary edema is a postsurgical life-threatening complication following PTPA, application of NPPV should be considered.

Accuracy of pulse oximeters in detecting hypoxemia in patients with chronic thromboembolic pulmonary hypertension.

Purpose Pulse oximetry is routinely used to continuously and non-invasively monitor arterial oxygen saturation (SaO2). When oxygen saturation by pulse oximeter (SpO2) overestimates SaO2, hypoxemia may be overlooked. We compared the SpO2 - SaO2 differences among three pulse oximeters in patients with chronic thromboembolic pulmonary hypertension (CTEPH) who spent their daily lives in a poor oxygen state. Material and Method This prospective observational study recruited 32 patients with CTEPH undergoing elective cardiac catheterization. As we collected arterial blood samples in the catheter laboratory, SpO2 values were simultaneously recorded. Three pulse oximeters were used on each patient, and SpO2 values were compared with oximetry readings using a blood gas analyzer. To determine the optimal SpO2 value by which to detect hypoxemia (SaO2≦90%), we generated receiver operating characteristic (ROC) curves for each pulse oximeter. Result The root mean square of each pulse oximeter was 1.79 (OLV-3100), 1.64 (N-BS), and 2.50 (Masimo Radical). The mean bias (SpO2 - SaO2) for the 90%–95% saturation range was significantly higher for Masimo Radical (0.19 +/- 1.78% [OLV-3100], 0.18 +/- 1.63% [N-BS], and 1.61 +/- 1.91% [Masimo Radical]; p<0.0001). The optimal SpO2 value to detect hypoxemia (SaO2≦90%) was 89% for OLV-3100, 90% for N-BS, and 92% for Masimo Radical. Conclusion We found that the biases and precision with which to detect hypoxemia differed among the three pulse oximeters. To avoid hypoxemia, the optimal SpO2 should be determined for each pulse oximeter.