Acquired laryngomalacia as a cause of post-extubation stridor and extubation failure following craniotomy: a case report.

BACKGROUND: Laryngomalacia is a dynamic airway condition characterized by flaccid laryngeal tissue and inward collapse of supraglottic structures during inspiration. Although it may cause airway obstruction and requires careful management, there have been few reports regarding laryngomalacia after surgery. We report a case of adult-onset laryngomalacia occurred after craniotomy requiring reintubation. CASE PRESENTATION: A 21-year-old man was admitted to the ICU after craniotomy for a cerebellopontine angle tumor. He developed severe stridor immediately after extubation on the postoperative day 2 and required reintubation. On the postoperative day 5, similar episode occurred following re-extubation and fiberoptic laryngoscopy revealed a collapsed epiglottis and left arytenoid into the glottis. A diagnosis of laryngomalacia was made, and he underwent tracheostomy. Laryngomalacia had completely improved; however, bilateral vocal cord paralysis was detected 2 weeks later. CONCLUSIONS: Acquired laryngomalacia should be considered as a possible mechanism of the airway symptoms in a patient with neurological dysfunction.

The relationship between years of anesthesia experience and first-time intubation success rate with direct laryngoscope and video laryngoscope in infants: a retrospective observational study.

PURPOSE: Studies in adults have reported that video laryngoscope is more useful than direct laryngoscope when training less experienced anesthesiologists. However, whether this is true for infants remains unclear. Therefore, this study aimed to evaluate whether the use of video laryngoscope would result in smaller differences in success rate according to anesthesiologists' expertise than those in direct laryngoscope. METHODS: Medical records and video recordings from the operating room of patients aged < 1 year who underwent non-cardiac surgery between March 2019 and September 2021 were reviewed. Tracheal intubations between April 8, 2020, and June 20, 2021, were excluded due to the shortage of video laryngoscope blades during the COVID-19 pandemic. Rates of first-time tracheal intubation success were compared by years of anesthesia experience and initial intubation device. RESULTS: In total, 125 of 175 tracheal intubations were analyzed (direct laryngoscope group, n = 72; video laryngoscope group, n = 53). The first-time tracheal intubation success rate increased with years of experience as an anesthesiologist in the direct laryngoscope group (odds ratio OR 1.70, 95% confidence interval CI 1.15, 2.49; P = 0.0070), but not the video laryngoscope group (OR 0.99, 95% CI 0.74, 1.35; P = 0.99). CONCLUSION: The differences in success rate according to the anesthesiologists' years of experience were non-significant when using video laryngoscope in infants, compared to those in direct laryngoscope.

Intraoperative myocardial infarction and refractory cardiogenic shock during major hepatectomy: a case report.

BACKGROUND: Myocardial infarction (MI) complicated by cardiogenic shock during non-cardiac surgery is a rare but fatal complication. The management of intraoperative MI is challenging. CASE PRESENTATION: A 77-year-old hypertensive man with good functional capacity was scheduled for hepatectomy. After the start of liver resection, the electrocardiogram monitor showed ST depression, and the patient developed refractory cardiogenic shock. Transesophageal echocardiography revealed severe hypokinesis of the anteroseptal wall. The surgery was suspended, and an intra-aortic balloon pump was placed following immediate abdominal closure. Coronary angiography revealed severe stenosis of the left main coronary trunk, and percutaneous coronary intervention (PCI) was performed. Myocardial wall motion improved, and blood pressure stabilized. Two days after PCI, hepatectomy, which had been suspended, was successfully completed. CONCLUSIONS: Once intraoperative MI has occurred, early diagnosis and multidisciplinary approaches are important to manage the difficult clinical situation.

Altered microvascular reactivity assessed by near-infrared spectroscopy after hepato-pancreato-biliary surgery.

Little is known about microcirculatory dysfunction following abdominal surgeries. This study aimed to evaluate changes in microvascular reactivity (MVR) before and after major abdominal surgery, assessed by near-infrared spectroscopy in conjunction with a vascular occlusion test. This prospective observational study included 50 adult patients who underwent hepato-pancreato-biliary surgery lasting ≥ 8 h. MVR was assessed by tissue oxygen saturation (StO2) changes in the plantar region of the foot during 3 min of vascular occlusion and subsequent release under general anesthesia before and after surgery. The primary outcome was alteration in the recovery slope of StO2 (RecStO2) and recovery time (tM) between the preoperative and postoperative values. Postoperative short-term outcome was represented by the Post-operative Morbidity Survey (POMS) score on the morning of postoperative day 2. After surgery, RecStO2 was reduced (0.74% [0.58-1.06]/s vs. 0.89% [0.62-1.41]/s, P = 0.001), and tM was longer (57.0 [42.9-71.0] s vs. 41.3 [35.5-56.5] s, P < 0.001), compared to the preoperative values. Macrohemodynamic variables such as cardiac index, arterial pressure, and stroke volume during postoperative measurement did not differ with or without relative MVR decline. In addition, the POMS score was not associated with postoperative alterations in microcirculatory responsiveness. MVR in the plantar region of the foot was reduced after major hepato-pancreato-biliary surgery regardless of macrocirculatory adequacy. Impaired MVR was not associated with short-term outcomes as long as macrocirculatory indices were well maintained. The impact of relative microcirculatory changes, especially combined with inadequate macrocirculation, on postoperative complications remains to be elucidated.Clinical Trial Registrations UMIN-CTR trial ID: 000033461.

Clinical features and significance of leukopenia occurring immediately after endovascular surgery.

PURPOSE: Inflammation after stent graft surgery is known as postimplantation syndrome (PIS) and it causes leukocytosis. However, we have experienced leukopenia in the very early postoperative phase of endovascular surgery at our institution. We investigated leukopenia, an under-recognized phenomenon that occurred after transcatheter aortic valve implantation (TAVI), endovascular aortic repair (EVAR), and thoracic endovascular aortic repair (TEVAR). METHODS: Records of patients who underwent TAVI, EVAR, and TEVAR between March 2018 and February 2019 were retrospectively reviewed. Primary outcomes were the decline rate of white blood cell count (DR-WBC) in the immediate postoperative period and its differences among surgical procedures. The secondary endpoint was the relationship between DR-WBC and infectious complications. Furthermore, the incidence of PIS and its differences among the procedures and associations with DR-WBC were evaluated. RESULTS: A total of 108 patients (TAVI 41, EVAR 37, TEVAR 30) were included. DR-WBC immediately after surgery was higher in the TAVI group when compared with other groups (TAVI, 43.1 ± 22.6%; EVAR, 27.6 ± 17.3%; TEVAR, 25.4 ± 27.4%; P < 0.01). DR-WBC was not significantly different regardless of postoperative infection (P = 0.45) or PIS (P = 0.62). The incidence rate of PIS was higher in the EVAR group compared with the TAVI group, and was not associated with DR-WBC. CONCLUSIONS: Leukopenia was a common phenomenon immediately after endovascular surgery, especially TAVI. It resolved a day after surgery and was not associated with PIS or infectious complications. Therefore, it seems to be a transient abnormal hematological finding and a self-limiting condition.

Diagnostic timing dependent characteristics of acute kidney injury following hepatectomy: a retrospective historical cohort analysis.

BACKGROUND: The timing of diagnosis of post-hepatectomy acute kidney injury (AKI) has rarely been investigated. The aim of this retrospective study was to reveal the differences between AKI subtypes following hepatectomy, as classified by timing of diagnosis. METHOD: Post-hepatectomy AKI was classified as very transient AKI (vtAKI; criteria satisfied by the serum creatinine value immediately after surgery) or non-transient AKI (ntAKI; all other AKI types except for vtAKI). Multivariate logistic regression analyses for both AKI types were performed separately to identify differences in known perioperative AKI risk factors. The impacts of each AKI subtype on postoperative complications, hospital stay and renal outcome at discharge were also evaluated. RESULTS: AKI was diagnosed in 135 of 750 patients (18.0%); 82 and 53 patients were classified as vtAKI and ntAKI, respectively. In multivariate analysis, even among the perioperative factors associated with whole AKI, there were distinct relationships depending on vtAKI or ntAKI. Furthermore, only ntAKI was associated with postoperative complications, longer hospital stays and impaired renal function at discharge. CONCLUSIONS: Based on the results of this study, future post-hepatectomy AKI studies should only include ntAKI and exclude vtAKI, as vtAKI has minimal clinical impact despite accounting for a significant proportion of AKI patients. CLINICAL TRIAL REGISTRATIONS: None.

Two-stage goal-directed therapy protocol for non-donor open hepatectomy: an interventional before-after study.

PURPOSE: Hemodynamic management during low central venous pressure (L-CVP)-assisted hepatectomy involves fluid restriction during resection and fluid resuscitation after resection. Recently, high stroke volume variation (SVV) has been reported as an alternative to L-CVP for reducing blood loss during a hepatectomy. The current study evaluated the impact of a newly implemented SVV-based goal-directed therapy (GDT) protocol on blood loss during hepatectomy. METHODS: We conducted a before-after comparative study, which included L-CVP-assisted hepatectomy cases (control group) and GDT-assisted hepatectomy cases (intervention group). The GDT protocol included SVV, cardiac index, and mean arterial pressure as hemodynamic parameters. The target SVV ranges were ≥ 13% and ≤ 12% before and after the resection, respectively. The primary endpoint was the proportion of patients whose blood loss was < 400 mL (median of our hepatectomy cases) in the GDT group, and it was compared to a predefined threshold of 50%. We also investigated factors associated with blood loss using multiple regression analysis. RESULTS: We included 66 patients in the control group and 50 in the GDT group. In the GDT group, the median blood loss was 220 mL and 36 patients (72%) lost < 400 mL blood. This was significantly greater than 50% (P < 0.001). Post-resection GDT-guided fluid optimization reduced positive intraoperative fluid balance compared to that achieved by the conventional fluid therapy used in the control. Multiple regression analysis showed that GDT application, epidural anesthesia, operative time, and hydroxyethyl-starch infusion volume were associated with blood loss. CONCLUSION: Compared to conventional management, SVV-guided GDT may reduce blood loss during hepatectomies.

Evaluation of external reference levels for central venous pressure measurements of severely obese patients in the supine position.

PURPOSE: A proper reference level is important for measuring intracardiac pressures, especially for parameters with small normal values such as central venous pressure (CVP). Although several external zero reference levels (eZRLs) have been proposed for non-obese patients, none has been reported for severely obese patients. The aim of this study was to investigate an appropriate eZRL for CVP measurements of severely obese patients. METHODS: Chest computed tomography images of 65 patients with body mass index (BMI) ≥ 35 kg/m2 were retrospectively reviewed. The anteroposterior thoracic diameter and height of the mid-right atrium (RA) were measured. Four reported eZRLs for CVP measurements (midthoracic level, two-thirds and four-fifths of the thoracic diameter above table level, and 5 cm below the anterior thorax) were examined for error when predicting the midpoint of the RA. RESULTS: The median BMI was 36.9 kg/m2 [interquartile range (IQR), 36.0-39.2]. There was a significant difference in the calculated errors for the midpoint of the RA among the four eZRLs (Kruskal-Wallis test, P < 0.001). Two-thirds of the thoracic diameter above table level was the most accurate reference level for CVP measurement (Steel-Dwass post hoc analysis, P < 0.001). The Bland-Altman plot showed acceptable agreement for clinical use (mean difference, - 7 mm; 95% limit of agreement, - 23 to 9 mm). CONCLUSION: The most accurate eZRL for CVP measurements of severely obese patients in the supine position was two-thirds of the thoracic diameter above table level. This result is consistent with that of a previous report of non-obese patients.

Left subclavian artery malperfusion due to thoracic outlet syndrome during total vertebrectomy for invasive lung cancer: a case report.

Thoracic outlet syndrome (TOS) can interrupt blood flow to upper limbs by vascular compression. We report a case of a 52-year-old man who presented left subclavian artery malperfusion due to TOS during total vertebrectomy (Th2-4) in the prone position for invasive lung cancer. At the time of resection of the vertebral bodies, his left radial systolic blood pressure had begun to drop intermittently and we noticed an interarm pressure difference. Accordingly, we began to monitor the right radial artery pressure and found that only the left radial artery pressure decreased as a result of compressive force from the surgical site. The operation was continued with intermittent malperfusion of the left arm, and when it was prolonged, we asked the surgeons to release the compression. No symptoms of ischemia or nerve injuries in the left arm were observed after the surgery. Retrospective review of his preoperative enhanced computed tomography images suggested a slightly compressed left subclavian artery in the costoclavicular space. Combination of the prone position and a specific upper limb position may be a risk factor for intraoperative TOS. An interarm blood pressure difference is a clue to detect accidental arterial TOS during general anesthesia.

[Interference between M-Entropy and Thermistor Probe Fixed on the Forehead during General Anesthesia].

We report a case in which M-Entropy was affected by the thermistor probe of tissue-core thermometer (Coretemp® TERUMO, Tokyo, Japan) fixed on the forehead. A 26-year-old man underwent osteosynthesis for forearm fracture under general anesthesia com- bined with brachial plexus block. General anesthesia was induced and maintained with fentanyl and target- controlled infusion of propofol. We use Coretemp* to measure core temperature and put the thermistor probe on forehead next to the M-Entropy sensor. Thirty minutes after start of the surgery, state and response entropy rose suddenly to extremely high lev- els. In spite of slow waves and sleep spindles on raw electroencephalogram (EEG) waveform, his vital signs showed no changes after the rise of entropy values. We suspected Coretemp® probe interfering with M- Entropy, and removed the probe from his forehead. M-Entropy returned to the default values immediately and this phenomenon was reproducible by attaching and detaching the probe. We therefore concluded that some electrical noise from the Coretemp® probe affected M-Entropy. The patient awoke from anesthesia smoothly, and had no memory of intraoperative awareness. This case suggests that we should always consider artifacts in EEG monitors and if their values do not correspond with clinical status, we should check raw EEG waveforms to judge the depth of anesthesia.

[Anesthetic and perioperative management of a patient with uncontrolled thyrotoxicosis undergoing coronary artery bypass grafting surgery].

Uncontrolled hyperthyroidism is a risk factor of perioperative thyrotoxic crisis. We report a case of a 61-year-old woman with thyrotoxicosis diagnosed with unstable angina pectoris. She needed to have an early scheduled coronay artery bypass grafting surgery, because percutaneous intervention for the left main coronary artery in support of intra-aortic balloon pumping (IABP) resulted in failure. Tachycardia and hyperthermia were observed at admission to the ICU, and hemodynamic parameters suggested high-output heart failure. Preoperative management using antithyroid drug, inorganic iodine, corticosteroid and propranolol stabilized her hemodynamic condition, and then CABG was performed on ICU day 3. Intraoperative and postoperative use of landiolol, a short acting beta blocker, was useful for maintaining hemodynamic stability. Surgery was uneventfully completed and she was extubated on postoperative day 1 following IABP withdrawal. Appropriate preoperative management and perioperative use of the short acting beta blocker were useful for management of the patient with uncontrolled hyperthyroid state.