Effect of Dexmedetomidine Preconditioning on Hepatic Ischemia-Reperfusion Injury in Acute Hyperglycemic Rats.

BACKGROUND: Acute hyperglycemia frequently occurs in stressful situations, including liver transplantation or hepatic surgery, which may affect the protective effects of dexmedetomidine preconditioning and increase postoperative mortality. Therefore, this study aimed to investigate the effects of dexmedetomidine on hepatic ischemia-reperfusion injury in acute hyperglycemia. METHODS: Thirty-six Sprague-Dawley rats were randomly assigned to 6 groups, including a combination between 2 glycemic (normo- and hyperglycemia) and 3 ischemia-reperfusion conditions (sham, ischemia-reperfusion only, and dexmedetomidine plus ischemia-reperfusion). Dexmedetomidine 70 µg/kg was preconditioned 30 minutes before ischemic injury. After 6 hours of reperfusion, serum aminotransferase levels were measured to confirm the hepatic tissue injury. Furthermore, inflammatory (nuclear factor-κb, tumor necrosis factor-α, and interleukin-6) and oxidative stress markers (malondialdehyde and superoxide dismutase) were detected. RESULTS: Ischemia-reperfusion injury significantly increased the serum levels of aminotransferase and inflammatory and oxidative stress markers. These ischemia-reperfusion-induced changes were further exacerbated in hyperglycemia and were significantly attenuated by dexmedetomidine preconditioning. However, the effects of dexmedetomidine in hyperglycemia were lesser than those in normoglycemia (P < .05 for aminotransferases, inflammatory markers, malondialdehyde, and superoxide dismutase). CONCLUSIONS: These findings suggest that the protective effects of dexmedetomidine preconditioning may be intact against hepatic ischemia-reperfusion injury in acute hyperglycemia. Although its effects appeared to be relatively reduced, this may be because of the increase in oxidative stress and inflammatory response caused by acute hyperglycemia. To determine whether the effects of dexmedetomidine itself would be impaired in hyperglycemia, further study is needed.

Catastrophic rhabdomyolysis following breast reconstruction operation using an abdominal flap: a case report.

Background: Rhabdomyolysis is a potentially fatal clinical syndrome resulting from the damage or breakdown of skeletal muscle, which can also lead to permanent disabilities. Based on our review of studies on rhabdomyolysis after prolonged surgeries, no other cases of rhabdomyolysis caused by muscle injury in the buttock area following breast reconstruction have been reported, making the current report the first to share information related to patient conditions and treatment progress in such cases. Case Description: Here, we present the case of a 57-year-old Asian patient with left breast cancer. We performed immediate breast reconstruction using a deep inferior epigastric perforator (DIEP) flap anastomosed to the internal mammary vessels after a skin-sparing mastectomy with sentinel lymph node biopsy. The surgery exceeded the estimated time because, after anastomosis, severe congestion was observed in the flap and because of the need to perform re-anastomosis and the reconstruction of the internal mammary vein twice. The surgical team eventually re-performed the breast reconstruction using a contralateral pedicled transverse rectus abdominis myocutaneous (TRAM) flap. The patient underwent breast reconstruction in a sitting position to ensure a symmetrical and natural breast shape resembling its original state. Additionally, a brown splint was placed underneath both legs to keep the hip and knees flexed to ensure donor-site closure when using an abdominal-based flap. The patient was closely monitored in the early postoperative period. On postoperative day (POD) 3, patient developed hypotension and was deemed to have experienced a hypovolemic shock. A complete laboratory workup was performed, and a rhabdomyolysis diagnosis was made based on the laboratory results. We believe that rhabdomyolysis resulted from prolonged pressure on the large gluteus maximus muscle located below the site of the pressure sore in the present patient. Conclusions: Postoperative rhabdomyolysis often results from prolonged surgery. Given the possibility of prolonged procedure time in patients undergoing breast reconstruction, the current case emphasizes the need to identify each patient's risk factors for rhabdomyolysis and prepare for possible rhabdomyolysis to prevent ischemic injuries and reduce the risk of complications such as hypovolemic shock.

Anesthetic management for inhibiting sympathetic activation in an adolescent patient diagnosed with catecholaminergic polymorphic ventricular tachycardia and undergoing left cardiac sympathetic denervation: A case report.

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a genetic disorder in which catecholamine release during exercise or emotional stress cause fatal tachyarrhythmias. In this paper, we discuss methods to minimize the sympathetic stimulation that can occur during the perioperative period in patients undergoing left cardiac sympathetic denervation to surgically treat CPVT.

Effect of Minimum Bronchial Cuff Volume of Left-Sided Double-Lumen Tube for One-Lung Ventilation on the Change in Bronchial Cuff Pressure during Lateral Positioning in Thoracic Surgery: A Prospective Observational Study.

The minimum bronchial cuff volume (BCVmin) of a double-lumen tube (DLT) without air leaks during lung isolation may vary among individuals, and lateral positioning could increase the bronchial cuff pressure (BCP). We investigated the effect of initially established BCVmin (BCVi) on the change in BCP by lateral positioning. Seventy patients who underwent elective lung surgery were recruited and divided into two groups according to the BCVi obtained during anesthetic induction in each patient. Outcome analysis was conducted using data from 39 patients with a BCVi greater than 0 (BCVi > 0 group) and 27 with a BCVi of 0 (BCVi = 0 group). The primary outcome was a change in the value measured in the supine and lateral positions of the initially established BCP (BCPi; BCP at the time of BCVi injection), which was significantly larger in the BCVi > 0 group than in the BCVi = 0 group (1.5 (0.5-6.0) cmH2O vs. 0.0 (0.0-1.0) cmH2O; p < 0.001). BCVi was related to the left main bronchus (LMB) diameter (Spearman's rho = 0.676, p < 0.001) and the gap between the LMB diameter and the outer diameter of the bronchial cuff (Spearman's rho = 0.553, p < 0.001). Therefore, selecting a DLT size with a bronchial cuff that fits each patient's LMB may be useful in minimizing the change in BCP when performing lateral positioning during thoracic surgery. If the bronchial cuff requires unavoidable initial inflation, it is necessary to be aware that BCP may increase during lateral positioning and to monitor the BCP regularly if possible.

Pressure changes in tapered and cylindrical shaped cuff after extension of head and neck: A randomized controlled trial.

BACKGROUND: The proper cuff pressure of endotracheal tube (ET) plays an important role in sealing the airway and preventing airway complications during mechanical ventilation. The ET cuff shape affects the cuff pressure after positional change. AIM: To investigate cuff pressure between tapered and cylindrical cuff after extension of head and neck during nasal endotracheal intubation. METHODS: In a randomized clinical trial, 52 patients were randomized to one of two groups: cylindrical cuff or Tapered cuff. Cuff pressure with 22 cmH2O was applied to patients in the neutral position. After extension of head and neck, the cuff pressure was evaluated again and readjusted to 22 cmH2O. In addition, the extent of cephalad migration of ET tip was assessed and postoperative airway complications such as sore throat, and hoarseness were measured. RESULTS: The cuff pressure was higher in the tapered cuff (28.7 ± 1.0 cmH2O) than in the cylindrical cuff (25.5 ± 0.8 cmH2O) after head and neck extension (P < 0.001). The extent of cephalad migration of tube tip was greater in TaperGuard ET (18.4 ± 2.2 mm) than in conventional ET (15.1 ± 1.2 mm) (P < 0.001). The incidence of postoperative airway complications was comparable between two groups. CONCLUSION: After head and neck extension, the cuff pressure and the extent of cephalad migration of ET was greater in tapered cuff than in cylindrical cuff during nasal intubation, respectively.

Fiberoptic-guided nerve integrity monitoring tube intubation assisted by video-laryngoscope with external laryngeal manipulation in a patient with anteriorly displaced larynx due to huge goiter with retropharyngeal involvement: A case report.

RATIONALE: Goiter, an abnormal enlargement of the thyroid gland, can induce airway distortion or tracheal compression. Airway management can be challenging for anesthesiologists, depending on the location and size of the mass as well as the patient's airway conditions, although it is reported that most cases can easily be managed by oral intubation. PATIENT CONCERNS: A 61-year-old female patient who had planned for a total thyroidectomy due to a huge goiter was intubated with nerve integrity monitoring (NIM) tubes, using video laryngoscopy (VL) and oral fiberoptic bronchoscopy (FOB) alone. The respective attempts initially failed. DIAGNOSIS: The patient's thyroid mass extended from the C3 cervical spine level to the T1 thoracic spine level with retropharyngeal involvement, causing an upper airway anatomical alteration that made intubation difficult. FOB manipulation was challenging due to the acute angulation of the laryngeal inlet and the tongue and the consequent interruption by the epiglottis. There was resistance to tube introduction, despite counterclockwise rotation of the NIM tube, due to acute angulation of the larynx and circumferential narrowing of the oropharyngeal and supraglottic space. INTERVENTIONS: In the first step of FOB-guided intubation, external laryngeal manipulation (ELM) was performed to improve the angle of the glottic opening and to elevate epiglottis tip. This allowed for FOB introduction into the trachea. VL was then performed transorally to elevate the tongue base and increase space, using the blade. ELM was applied simultaneously to move the glottis lower, thereby reducing the angle of the tube passage. OUTCOMES: The NIM tube was successfully introduced into the trachea with counterclockwise rotation in FOB-guided intubation. LESSONS: The combination of techniques using basic and popular devices and maneuvers, such as ELM and VL, may be useful for the successful management of difficult airways related to retropharyngeal goiter, without the need for surgical airway.

Sinus pause during nerve integrity monitoring tube insertion following anesthetic induction with a low-dose neuromuscular blocking agent: A CARE-compliant case report.

RATIONALE: Nerve integrity monitoring (NIM) tubes are commonly used in thyroid surgery to prevent recurrent laryngeal nerve injury. To achieve the optimal electromyographic signal for NIM as intraoperative neural monitoring (IONM), the neuromuscular blocking agent (NMBA) dose should be low. The use of a low-dose NMBA increases the anesthetic and analgesic agent dose required to attenuate the laryngeal reflex during intubation. In addition, since the NMBA onset time is delayed, depending on the situation, anesthesia may become excessively deep or shallow before intubation. PATIENTS CONCERN: A 51-year-old woman scheduled for thyroid lobectomy received 0.3 mg/kg of rocuronium. Three minutes later, when the NIM tube was inserted through the vocal cord, the patient's heart rate (HR) was undetectable for 2 seconds. DIAGNOSIS: We suspected that the use of a high-dose anesthetic agent and remifentanil or the laryngocardiac reflex induced the sinus pause. INTERVENTIONS: To maintain the anesthetic depth, we administered 6 vol% of desflurane. Because the patient's systolic blood pressure was 70 mmHg and HR was 30 beats/min, we discontinued the remifentanil infusion and administered 8 mg of ephedrine. OUTCOMES: The patient's vital signs recovered to normal levels. Subsequently, there were no episodes of bradycardia or arrhythmia. CONCLUSION: Sinus pause or severe bradycardia may occur due to the laryngocardiac reflex or the administration of a high-dose anesthetic and analgesic agent during tracheal intubation in patients who received a low-dose NMBA for IONM induction using an NIM tube. Anesthesiologists should be aware of these risks and take precautions to maintain adequate anesthesia, be prepared to administer vasoactive drugs to increase the blood pressure and HR if needed, and, if possible, intravenously administer lidocaine to attenuate the laryngeal reflex during intubation.

Use of the Human Broncho® Double-Lumen Tube in a Tracheal Bronchus Patient After Failed Lung Isolation with a Broncho-Cath™: A Case Report.

Airway management for one-lung ventilation may be challenging for anesthesiologists depending on the location of the tracheal bronchus orifice and possible anatomical distortions. Polyvinyl chloride double-lumen tube Broncho-Cath™ has been successfully used for one-lung ventilation in most cases of tracheal bronchus arising within 2 cm above the carina. However, there have been reports of occasional failure. A 78-year-old male patient diagnosed with secondary pneumothorax was scheduled for video-assisted thoracic surgery, and the tracheal bronchus originating 1.9 cm above the carina was shown in the preoperative chest computed tomography. Although a left-sided Broncho-Cath was initially placed, one-lung ventilation could not be achieved. Under bronchoscopy view through the tracheal lumen, the tracheal bronchus orifice was found to be partially obstructed. Furthermore, the bronchial cuff was herniated from the left main bronchus, leading to a failure of one-lung ventilation. The Broncho-Cath was replaced with a silicone double-lumen tube Human Broncho®, which has more flexible bronchial segment and an increased marginal gap between the bronchial cuff and the tracheal lumen opening. The Human Broncho was successfully placed in an optimal position within the left main bronchus without blocking the tracheal bronchus orifice, thereby achieving the successful one-lung ventilation. The structurally unique Human Broncho may be considered as an alternative option in thoracic surgery of tracheal bronchus patients if lung isolation cannot be achieved with the Broncho-Cath.

Behavioral changes after hospital discharge in preschool children experiencing emergence delirium after general anesthesia: A prospective observational study.

BACKGROUND: Emergence delirium is well known as early postoperative behavioral change after general anesthesia. However, it is unclear whether children with emergence delirium have negative behavioral changes after hospital discharge. AIM: This observational study investigated the association between emergence delirium and posthospital behavioral changes. METHODS: One-hundred preschoolers aged 2-7 years undergoing elective surgery were enrolled in 2 tertiary university hospitals. Preoperative anxiety level was assessed using modified Yale preoperative anxiety scale. Emergence delirium was defined via pediatric anesthesia emergence delirium score ≥12 at any time in the recovery room. We divided the delirium score into a delirium-specific score (the sum of the first 3 items: eye contact, purposeful movement, and awareness of surrounding) and a pain-related score (the sum of the last 2 items: restlessness and inconsolability). High delirium scores represent severe emergence delirium. Posthospital behavioral changes were assessed by a change in Child Behavior Checklist 1.5-5 scores before and 1 week after surgery. The primary outcome was the total behavior checklist scores 1 week after surgery. Multiple linear regression was performed to identify risk factors for posthospital behavioral changes. RESULTS: Children with emergence delirium (n = 58) had higher postoperative behavior checklist scores than children without emergence delirium (n = 42) [mean (SD), 22.8 (17.5) vs. 14.0 (12.1); mean difference (95% CI), 8.8 (1.5-16.2)]. Increases in preoperative anxiety level [regression coefficient (b) (95% CI) =0.241 (0.126-0.356)] and peak delirium-specific score [b = 0.789 (0.137-1.442)] were associated with an increase in behavior checklist score 1 week after surgery, while pain-related score, type of surgery, premedication, and age were not. CONCLUSION: Children with emergence delirium developed more severe behavior changes 1 week after surgery than those without emergence delirium. High preoperative anxiety level and emergence delirium scores were associated with posthospital behavioral changes.

Changes in the Bronchial Cuff Pressure of Left-Sided Double-Lumen Endotracheal Tube by Lateral Positioning: A Prospective Observational Study.

Proper bronchial cuff pressure (BCP) is important when using a double-lumen endotracheal tube (DLT), especially in thoracic surgery. As positional change during endotracheal tube placement could alter cuff pressure, we aim to evaluate the change in BCP of DLT from the supine to the lateral decubitus position during thoracic surgery. A total of 69 patients aged 18-70 years who underwent elective lung surgery were recruited. BCP was measured at a series of time points in the supine and lateral decubitus positions after confirming the DLT placement. The primary outcome was change in the initial established BCP (BCPi), which is the maximum pressure at which the BCP did not exceed 40 cmH2O without air leak in the supine position, after lateral decubitus positioning. As the primary outcome, the BCPi increased from 25.4 ± 9.0 cmH2O in the supine position to 29.1 ± 12.2 cmH2O in the lateral decubitus position (p < 0.001). Out of the 69 participants, 43 and 26 patients underwent surgery in the left-lateral decubitus position (LLD group) and the right-lateral decubitus position (RLD group) respectively. In the LLD group, the BCPi increased significantly (p < 0.001) after lateral positioning and the beginning of surgery and the difference value, ∆BCPi, from supine to lateral position was significantly higher in the LLD group than in the RLD group (p = 0.034). Positional change from supine to lateral decubitus could increase the BCPi of DLT and the increase was significantly greater in LLD that in RLD.

Frontal electroencephalogram activity during emergence from general anaesthesia in children with and without emergence delirium.

BACKGROUND: Emergence delirium (ED) in children after general anaesthesia causes significant distress in patients, their family members, and clinicians; however, electroencephalogram (EEG) markers predicting ED have not been fully investigated. METHODS: This prospective, single-centre observational study enrolled children aged 2-10 yr old under sevoflurane anaesthesia. ED was assessed according to Diagnostic and Statistical Manual of Mental Disorders (DSM) IV or 5 criteria. The relative power of low-frequency (delta and theta) and high-frequency (alpha and beta) EEG waves during the emergence period was compared between the children with and without ED. The linear relationships between the relative power and peak Paediatric Assessment of Emergence Delirium (PAED) score were investigated. RESULTS: Among the 60 patients, 22 developed ED (ED group), whereas the other 38 did not (non-ED group). The relative power of the delta wave was higher (mean [standard deviation], 0.579 [0.083] vs 0.453 [0.090], respectively, P<0.001) in the ED group, whereas that of the alpha and beta waves was lower in the ED group, than in the non-ED group (0.155 [0.063] vs 0.218 [0.088], P=0.005 and 0.114 [0.069] vs 0.186 [0.070], P<0.001, respectively). The areas under the receiver operating characteristic curves of the relative power of the delta wave, low-to-high frequency power ratio, and delta-to-alpha ratio were 0.837 (95% confidence interval, 0.737-0.938), 0.835 (0.735-0.934), and 0.768 (0.649-0.887), respectively. The relative power of the delta wave and the two ratios had a positive linear relationship with the peak PAED scores. CONCLUSIONS: Paediatric patients developing ED have increased low-frequency (delta) frontal EEG activity with reduced high-frequency (alpha and beta) activity during emergence from general anaesthesia. CLINICAL TRIAL REGISTRATION: NCT03797274.

Effect of lateral positioning on the bronchial cuff pressure of a left-sided double-lumen endotracheal tube during thoracic surgery: study protocol for a prospective observational study.

INTRODUCTION: Correct pressure is important when using a double-lumen endotracheal tube (DLT), especially in thoracic surgery. An inadequate bronchial cuff pressure (BCP) can cause air leak and interfere with visualisation of the surgical field, whereas an excessive pressure BCP can lead to cuff-related complications. Based on several reports that cuff pressure could alter after a positional change when using an endotracheal tube, we hypothesise that a change from the supine position to the lateral decubitus position, which is essential for thoracic surgery, would affect the BCP of the DLT. METHODS AND ANALYSIS: This prospective, single-centre, observational study will enrol 74 patients aged 18-70 years undergoing elective lung surgery from September 2018 to April 2019. The primary outcome will be the change in the 'initially established BCP' (maximum BCP not exceeding 40 cm H2O with no air leak in the supine position) after lateral decubitus positioning. BCP and air leak will be assessed in each patient position during inflation of the cuff with air in 0.5 mL increments from 0 to 3 mL. Secondary outcomes will include the incidence of BCP exceeding 40 cm H2O after the initial established value and that of a change in the smallest bronchial cuff volume without air leak after a change to the lateral position. The relationship between the change in BCP and airway pressure, compliance and body mass index after lateral positioning will be investigated. ETHICS AND DISSEMINATION: The study will be conducted in accordance with the Declaration of Helsinki and supervised by the Daegu Catholic University Medical Center institutional review board (study approval number CR-18-111). All patients will receive information about the study and will need to provide written informed consent before enrolment. The results will be presented at an international meeting and published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT03656406; Pre-results.

Comparison of the clinical performance of the flexible laryngeal mask airway in pediatric patients under general anesthesia with or without a muscle relaxant: study protocol for a randomized controlled trial.

BACKGROUND: The insertion of a laryngeal mask airway (LMA) is difficult in children due to the unique features of their airways. Muscle relaxants have been reported to facilitate LMA insertion in adults; however, there is a lack of evidence supporting this in children. This trial is designed to assess the feasibility of LMA insertion with and without the use of muscle relaxants in pediatric patients under general anesthesia. METHODS/DESIGN: This is a prospective, double-blind, single-center, parallel-arm, non-inferiority, randomized controlled trial to be conducted with participants aged 2-7 years who are undergoing elective ophthalmic surgery under general anesthesia. Participants are randomly assigned to one of two groups based on whether muscle relaxants are used (MR group, n = 64) or not used (Saline group, n = 64) prior to LMA insertion. The primary outcome is the oropharyngeal leak pressure (OLP) at a fixed gas flow of 3 L/min. The secondary outcomes are intubation time for successful insertion, ease of insertion and mask bagging, intubation attempt for successful insertion, successful insertion rate on the first attempt, fiberoptic view of the LMA position, postoperative complications, and changes in hemodynamic and ventilatory parameters. DISCUSSION: We will compare the OLPs to determine whether the muscle relaxant provides better conditions for the manipulation of the LMA. This is the first randomized controlled trial to investigate whether muscle relaxants are beneficial to the clinical performance of LMA insertion in pediatric patients under general anesthesia. This trial will be a resource for improving the process and safety of pediatric LMA insertion under general anesthesia. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03487003 . Registered on 18 April 2018.

Comparing the placement of a left-sided double-lumen tube via fiberoptic bronchoscopy guidance versus conventional intubation using a Macintosh laryngoscope, to reduce the incidence of malpositioning: study protocol for a randomized controlled pilot trial.

BACKGROUND: A fiberoptic bronchoscope (FOB) is commonly used to identify the proper placement of a double-lumen endotracheal tube (DLT) for good lung isolation during thoracic surgery. We hypothesized that the FOB-guided method for DLT placement composed of tracheal intubation under initial guidance by a FOB via the bronchial lumen and subsequent selective left-bronchial intubation could be used to reduce the incidence of DLT malposition and reduce the time required for completion of DLT placement and confirmation of proper DLT position during intubation using a left-sided DLT, in comparison to the conventional method under direct laryngoscopy using a Macintosh laryngoscope. METHODS/DESIGN: In this randomized controlled pilot trial, 50 patients, aged 18-70 years, scheduled for elective thoracic surgery will be recruited and randomly assigned to two groups according to the method of DLT placement: a FOB-guided method (F) group and a conventional method (C) group. Regardless of the group, the DLT placement processes will be followed by subsequent confirmation processes, using a FOB. If the DLT is misplaced, the position would be corrected. The primary outcome is the incidence of DLT malpositioning observed via a FOB during confirmation after DLT placement. The secondary outcomes consist of the time required to achieve the entire DLT intubation process, which is the sum of the duration of DLT placement and the duration of confirmation of the proper position, the incidence of failed tracheal intubation on the first and second attempt, and complications associated with the intubation process. DISCUSSION: This pilot study was designed as the first randomized controlled trial to confirm our hypothesis. This should provide information for a further full-scale trial, and the outcomes of the study should provide clinical evidence on the usefulness of the FOB-guided method for DLT placement, in comparison to the conventional method. TRIAL REGISTRATION: Clinical Research Information Service; CRIS, ID: KCT0002663 . Retrospectively registered on 24 January 2018.

Fiberoptic bronchoscopic treatment of blood aspiration and use of sugammadex in a patient with epistaxis: A case report.

RATIONALE: In patients with oropharyngeal and nasopharyngeal bleeding, blood aspiration can make airway management difficult and lead to severe pulmonary complications. PATIENT CONCERNS: A 44-year-old male patient with recurrent epistaxis underwent surgery for hemostasis. The patient aspirated blood through the endotracheal tube when he hiccupped during the surgery. DIAGNOSIS: The patient was diagnosed with blood aspiration after intraoperative fiberoptic bronchoscopy revealed a blood clot and viscous mucus in the airways, but no sign of active bleeding. INTERVENTIONS: Tracheobronchial suctioning and irrigation with normal saline was performed through the bronchoscope to remove the aspirated blood clot. Prior to emergence from anesthesia, sugammadex was administered to induce complete neuromuscular recovery and enable the patient to cough up any blood remaining in the airways. OUTCOMES: The patient was successfully extubated and fully recovered with no complications. LESSONS: Blood aspiration due to oropharyngeal or nasopharyngeal bleeding can be diagnosed and treated by tracheobronchial suctioning via fiberoptic bronchoscopy. In addition, sugammadex can enable patients to recover spontaneous breathing, facilitate extubation, and enable patients to cough up any blood remaining in the airways.

Effects of small tidal volume and positive end-expiratory pressure on oxygenation in pressure-controlled ventilation-volume guaranteed mode during one-lung ventilation.

Background: The purpose of this study was to investigate whether tidal volume (TV) of 8 mL/kg without positive end-expiratory pressure (PEEP) and TV of 6 mL/kg with or without PEEP in pressure-controlled ventilation-volume guaranteed (PCV-VG) mode can maintain arterial oxygenation and decrease inspiratory airway pressure effectively during one-lung ventilation (OLV). Methods: The study enrolled 27 patients undergoing thoracic surgery. All patients were ventilated with PCV-VG mode. During OLV, patients were initially ventilated with TV 8 mL/kg (group TV8) without PEEP. Ventilation was subsequently changed to TV 6 mL/kg with PEEP (5 cmH2O; group TV6+PEEP) or without (group TV6) in random sequence. Peak inspiratory pressure (Ppeak), mean airway pressure (Pmean), and arterial blood gas analysis were measured 30 min after changing ventilator settings. Ventilation was then changed once more to add or eliminate PEEP (5 cmH2O), while maintaining TV 6 mL/kg. Thirty min after changing ventilator settings, the same parameters were measured once more. Results: The Ppeak was significantly lower in group TV6 (19.3±3.3 cmH2O) than in group TV8 (21.8±3.1 cmH2O) and group TV6+PEEP (20.1±3.4 cmH2O). PaO2 was significantly higher in group TV8 (242.5±111.4 mmHg) than in group TV6 (202.1±101.3 mmHg) (p=0.044). There was no significant difference in PaO2 between group TV8 and group TV6+PEEP (226.8±121.1 mmHg). However, three patients in group TV6 were dropped from the study because PaO2 was lower than 80 mmHg after ventilation. Conclusion: It is postulated that TV 8 mL/kg without PEEP or TV 6 mL/kg with 5 cmH2O PEEP in PCV-VG mode during OLV can safely maintain adequate oxygenation.

The anhepatic phase extended by temporary portocaval shunt does not affect anesthetic sensitivity and postoperative cognitive function: A case-control study.

Temporary portocaval shunt (TPCS) prolongs the duration of the anhepatic phase, during which anesthetic sensitivity is highest among the 3 phases of living donor liver transplantation (LDLT). Cognitive dysfunction has been associated with increased anesthetic sensitivity and poor hepatic function. Therefore, we assessed anesthetic sensitivity to desflurane and perioperative cognitive function in patients undergoing LDLT, in whom the duration of the anhepatic phase was extended by TPCS to test the hypothesis that the prolonged anhepatic phase increases anesthetic sensitivity and causes postoperative cognitive decline.This case-control study was conducted in 67 consecutive patients undergoing LDLT from February 2014 to January 2016. Anesthesia was maintained at a 0.6 end-tidal age-adjusted minimum alveolar concentration of desflurane. The bispectral index (BIS) was maintained at less than 60 and averaged at 1-minute intervals. The mini-mental state examination (MMSE-KC) was performed 1 day before and 7 days after the LDLT. All parameters were compared between the patients undergoing TPCS (TPCS group) and the remaining patients (non-TPCS group).TPCS was performed in 16 patients (24%). TPCS prolonged the duration of the anhepatic phase (125.9 ±â€Š29.4 vs 54.9 ±â€Š20.5 minutes [mean ±â€Šstandard deviation], P < 0.0001). The averaged BIS values during the 3 phases were comparable between the 2 groups. No significant interval changes in the averaged BIS values were observed during the 3 consecutive phases. Similarly, there were no significant differences in MMSE-KC score assessed 1 day before and 7 days after LDLT between the 2 groups. The preoperative MMSE-KC scores were unchanged postoperatively in the 2 groups.The extension of the anhepatic phase did not affect anesthetic sensitivity and postoperative cognitive function.

Effect of recruitment maneuver on arterial oxygenation in patients undergoing robot-assisted laparoscopic prostatectomy with intraoperative 15 cmH2O positive end expiratory pressure.

BACKGROUND: This randomized, controlled study was designed to compare the effects of recruitment maneuvers (RMs) with a 15 cmH2O positive end-expiratory pressure (PEEP) on the systemic oxygenation and lung compliance of patients with healthy lungs following robot-assisted laparoscopic prostatectomy (RALP). METHODS: Sixty patients undergoing a RALP with an intraoperative 15 cmH2O PEEP were randomly allocated to an RM or a Control group. The patients in the RM group received a single RM through the application of a continuous positive airway pressure of 40 cmH2O for 40 s 15 min after being placed in the Trendelenburg position. The arterial oxygen tension (PaO2, primary endpoint) and the pulmonary dynamic and static compliances (secondary endpoints) were measured 10 min after the anesthetic induction (T1), 10 min after establishment of the pneumoperitoneum (T2), 10 min after establishment of the Trendelenburg position (T3), 10 min after the RM (T4), 60 min after the RM (T5), and 10 min after deflation of the pneumoperitoneum in the supine position (T6). RESULTS: The intergroup comparisons of the PaO2 showed significantly higher values in the RM group than in the Control group at T4 and T5 (193 ± 35 mmHg vs. 219 ± 33 mmHg, P = 0.015, 188 ± 41 mmHg vs. 214 ± 42 mmHg, P = 0.005, respectively). However, the PaO2 at T6 was similar in the two groups (211 ± 39 mmHg vs. 224 ± 41 mmHg, P = 0.442). Moreover, there were no statistical differences between the groups in the dynamic and static compliances of the lungs at any time point. CONCLUSIONS: The arterial oxygenation of the patients with a healthy lung function who had undergone a RALP with intraoperative 15 cmH2O PEEP was improved by a single RM. However, this benefit did not last long, and it did not lead to an amelioration of the lung mechanics.

Liver graft hyperperfusion in the early postoperative period promotes hepatic regeneration 2 weeks after living donor liver transplantation: A prospective observational cohort study.

Hepatic regeneration is essential to meet the metabolic demands of partial liver grafts following living donor liver transplantation (LDLT). Hepatic regeneration is promoted by portal hyperperfusion of partial grafts, which produces shear stress on the sinusoidal endothelium. Hepatic regeneration is difficult to assess within the first 2 weeks after LDLT as the size of liver graft could be overestimated in the presence of postsurgical graft edema. In this study, we evaluated the effects of graft hyperperfusion on the rate of hepatic regeneration 2 weeks after LDLT by measuring hepatic hemodynamic parameters. Thirty-six patients undergoing LDLT were enrolled in this study. Hepatic hemodynamic parameters including peak portal venous flow velocity (PVV) were measured using spectral Doppler ultrasonography on postoperative day 1. Subsequently, we calculated the ratio of each velocity to 100 g of the initial graft weight (GW) obtained immediately after graft retrieval on the day of LDLT. Ratios of GW to recipient weight (GRWR) and to standard liver volume (GW/SLV) were also obtained. The hepatic regeneration rate was defined as the ratio of the regenerated volume measured using computed tomographic volumetry at postoperative week 2 to the initial GW. Correlations of the hemodynamic parameters, GRWR, and GW/SLV with the hepatic regeneration rate were assessed using a linear regression analysis. The liver grafts regenerated to approximately 1.7 times their initial GW (1.7 ±â€Š0.3 [mean ±â€Šstandard deviation]). PVV/100 g of GW (r = 0.224, ß1 [slope coefficient] = 2.105, P = 0.004) and velocities of the hepatic artery and vein per 100 g of GW positively correlated with the hepatic regeneration rate, whereas GRWR (r = 0.407, ß1 = -81.149, P < 0.001) and GW/SLV (r = 0.541, ß1 = -2.184, P < 0.001) negatively correlated with the hepatic regeneration rate. Graft hyperperfusion demonstrated by increased hepatic vascular velocities and a small-sized graft in the early postoperative period contributes to hepatic regeneration 2 weeks after LDLT.