Accuracy of Transcutaneous Carbon Dioxide Measurement During Transcatheter Aortic Valve Replacement Under Monitored Anesthesia Care: A Prospective Observational Study.

Background Transcutaneous carbon dioxide tension (PtcCO2) measurement is a promising alternative to arterial carbon dioxide tension (PaCO2) measurement. PaCO2 measurement is invasive and intermittent, whereas PtcCO2 measurement is non-invasive and continuous. However, previous studies evaluating PtcCO2measurements did not include patients undergoing transcatheter aortic valve replacement (TAVR), who experience anticipated hemodynamic changes, particularly before and after valve placement. Therefore, we investigated whether PtcCO2 measurement could provide an alternative to PaCO2 measurement during transfemoral TAVR under monitored anesthesia care (MAC) with local anesthesia. Methodology We conducted a prospective observational study. We included all consecutive patients with severe aortic stenosis who were scheduled to undergo a transfemoral TAVR under MAC at our institution from November 1, 2020, to April 30, 2021. During the procedures, PaCO2 and PtcCO2 were concurrently monitored six times as a reference standard and index test, respectively. PtcCO2 was monitored continuously using a non-invasive earlobe sensor. The agreement between PtcCO2 and PaCO2 measurements was assessed using the Bland-Altman method, and the 95% limits of agreement were calculated. Based on previous studies, we determined that 95% limits of agreement of ±6.0 mmHg would be clinically acceptable to define PtcCO2 as an alternative to PaCO2. Results We obtained 88 measurement pairs from 15 patients. The lower and upper 95% limits of agreement between the PtcCO2 and PaCO2 measurements were -4.22 mmHg and 6.56 mmHg, respectively. Conclusions During TAVR under MAC with local anesthesia, PtcCO2 measurement could not provide a viable alternative to PaCO2 measurement to reduce high PaCO2 events. This study focused on comparing intraoperative periods before and after valve implantation. Therefore, further investigation is warranted to assess the impact of various factors, including the prosthetic valve type and the hemodynamic effects of balloon aortic valvuloplasty, on PtcCO2 measurement in TAVR.

Retrolaminar Block Versus Paravertebral Block for Pain Relief After Less-Invasive Lung Surgery: A Randomized, Non-Inferiority Controlled Trial.

Introduction A retrolaminar block (RLB) is a modified paravertebral technique with a local anesthetic injected at the retrolaminar site. The aim of this non-inferiority, parallel-group, prospective, and randomized study was to compare the analgesic efficacy of the paravertebral block (PVB) and RLB after lung surgery. Methods Eligible subjects were patients aged more than 20 years, with American Society of Anesthesiologists physical status Ⅰ or II, who were scheduled to undergo video-assisted thoracoscopic surgery (VATS) or limited thoracotomy because of lung disease. Patients were randomly allocated to receive either a PVB or RLB using a computer-generated sequence and sealed opaque envelopes. The PVB and RLB were induced by injecting 20 mL of 0.50% ropivacaine and 40 mL 0.25% ropivacaine, respectively. As the primary outcome variable, we considered the area under the curve (AUC) of the postoperative pain intensity using the trapezoidal method. Pain intensity was assessed using an 11-point numerical rating scale (NRS). We converted the NRS (0-10) into the visual analog scale (VAS) (0-100 mm) proportionally. We compared the AUC of the converted NRS (AUC-cNRS) on coughing between one and two hours after the operation. The non-inferiority margin was set at 25 mm × h in the AUC-cNRS. Patients and nurses were blinded to group assignments. Secondary outcomes included time to perform the block, NRS for pain intensity at rest and on coughing at one, two, four, 24, and 48 hours after the operation, the incidence of postoperative nausea and vomiting, time to first morphine use after the operation, and cumulative morphine consumption at 24 and 48 hours after the operation. Results In each group, 25 patients were randomized and analyzed. No significant difference in the AUC-cNRS was noted between the groups (P = 0.117). The mean difference in the AUC-cNRS (group RLB minus group PVB) was 13.42 mm × h, 95% confidence interval, -3.48 to 30.32 mm × h. However, when patients with unexpectedly extended skin incision were excluded from the analysis, the AUC-cNRS of group RLB was significantly higher as compared to group PVB (P = 0.0388). The time to perform the block was longer in PVB as compared to the RLB group (P < 0.0001). No significant differences were noted in the remaining secondary outcomes. Conclusion The non-inferiority of RLB as compared to PVB was not confirmed. Though RLB has the advantage of a shorter time to perform, RLB is not recommended for patients undergoing VATS or limited thoracotomy because of lack of efficacy as compared to PVB.

[A Case of Aortic Cannula Malposition Detected by Prolonged Desaturation of Regional Cerebral Oxygen Index (rcSO2)].

A sixteen-year-old female patient with congenital aortic stenosis underwent Ross procedure. We monitored bilateral regional cerebral saturation of oxygen (rcSO2) on the forehead at the right and left of the midline. After aortic and bicavel cannulation, cardiopulmonary bypass was instituted. On the mor- row of aortic cross clamping, the rcSO2 fell from approximately 55% to below 30%. We searched the cause of this phenomenon, and detected that the tip of aortic cannula was inserted to the left subclavian artery. After repositioning, the bilateral rcSO2 increased to above 65%. We felt keenly that the monitoring of rcSO2 is useful to recognize corrective adjustment of the cannula ori- entation, and the avoidance of cerebral hypoperfusion during the cardiopulmonary bypass period.

[Catecholamine Cardiomyopathy Presenting Inverted-takotsubo Pattern Asynergy].

Pheochromocytoma is complicated with catecholamine cardiomyopathy, and preoperative care becomes considerably more difficult We report anesthetic management for an 48-year-old man brought to our hospital by ambulance and immediately hospitalized due to pheochromocytoma crisis complicated with catechol- amine cardiomyopathy presenting inverted-takotsubo pattern asynergy. Before surgery, α and ß blocking drugs were used to control hypertension and tachycardia, and continuous hemodiafiltration was initiated and the patient was intubated for severe pulmonary edema. Seven days later, he underwent laparoscopic adrenalectomy. Total intravenous anesthesia was achieved with propofol, remifentanil, fentanyl, and rocuronium. During the operation, continuous infusion of landiolol, phentolamine, and nitroglycerin, and addi- tional bolus injections of landiolol were given to control hypertension. After severing the right adrenal vein, noradrenaline (0.15 µg · kg⁻¹ · min⁻¹), and dopamine (4µg · kg⁻¹ · min⁻¹) were started and the patient was placed in the intensive care unit Inverted-takotsubo pattern asynergy is not very common, and treatment consists of supportive care, as in the usual takotsubo. Preoperative CHDF (continuous hemodiafiltration) may be useful when it is difficult to control hypertension or tachycardia with medications.

[General Anesthesia for Septal Myectomy in a Patient with Noonan Syndrome, Severe Hypertrophic Obstructive Cardiomyopathy and Right Ventricular Outflow Tract Obstruction].

We report a case of an 18-year-old man with Noonan syndrome, severe hypertrophic obstructive cardiomy- opathy and right ventricular outflow tract obstruction who underwent septal myectomy under general anes- thesia. In our case, the ventricular outflow tract pres- sure gradients were 108 mmHg at left and 79 mmHg at right. General anesthesia was induced deliberately by fentanyl, midazolam and sevoflurane. Anesthesia was maintained with sevoflurane. For treatment of hypotension, we performed volume loading and admin- istration of phenylephrine. We did not use drugs that increase heart rate or contractility. Preload and after- load were well maintained, and the operation and gen- eral anesthesia were completed without serious prob- lem.

[Anesthetic Management of Single-staged Definitive Repair of Pulmonary Atresia with Ventricular Septum Defect and Major Aorto-pulmonary Collateral Arteries (PA/VSD, MAPCA)in an Adult].

A 25-year-old woman with unrepaired pulmonary atresia, ventricular septal defect and major aorto-pul- monary collateral artery was scheduled for single- staged definitive repair. She was complicated with mod- erate pulmonary hypertension, and had 2 MAPCAs arising from the descending artery. Cardiac catheter- ization demonstrated that right ventricular pressures were approximately equal to the left ventricular pres- sure. Pre-bypass, we maintained her PVR not too high in order to maintain her pulmonary blood flow. Post- bypass, we used hemodynamic support with dopamine, olprinone and nitroglycerin, maintaining her PVR opti- mally low. We inserted a catheter introducer in her jugular vein to deal with massive hemorrhage. After the repair, her right ventricular pressures were 7/10 of systemic pressure, and her postoperative course was uneventful.