Preoperative high-sensitivity troponin I and B-type natriuretic peptide, alone and in combination, for risk stratification of mortality after liver transplantation / 대한마취과학회지

Background@#Given the severe shortage of donor liver grafts, coupled with growing proportion of cardiovascular death after liver transplantation (LT), precise cardiovascular risk assessment is pivotal for selecting recipients who gain the greatest survival benefit from LT surgery. We aimed to determine the prognostic value of pre-LT combined measurement of B-type natriuretic peptide (BNP) and high-sensitivity troponin I (hsTnI) in predicting early post-LT mortality. @*Methods@#We retrospectively evaluated 2,490 consecutive adult LT patients between 2010 and 2018. Cut-off values of BNP and hsTnI for predicting post-LT 90-day mortality were calculated. According to the derived cut-off values of two cardiac biomarkers, alone and in combination, adjusted hazard ratios (aHR) of post-LT 90-day mortality were determined using multivariate Cox regression analysis. @*Results@#Mortality rate after 90 days was 2.9% (72/2,490). Rounded cut-off values for post-LT 90-day mortality were 400 pg/ml for BNP (aHR 2.02 [1.15, 3.52], P = 0.014) and 60 ng/L for hsTnI (aHR 2.65 [1.48, 4.74], P = 0.001), respectively. Among 273 patients with BNP ≥ 400 pg/ml, 50.9% of patients were further stratified into having hsTnI ≥ 60 ng/L. Combined use of pre-LT cardiac biomarkers predicted post-LT 90-day mortality rate; both non-elevated: 1.0% (21/2,084), either one is elevated: 9.0% (24/267), and both elevated: 19.4% (27/139, log-rank P < 0.001; aHR vs non-elevated 4.23 [1.98, 9.03], P < 0.001). @*Conclusions@#Concomitant elevation of both cardiac biomarkers posed significantly higher risk of 90-day mortality after LT. Pre-LT assessment cardiac strain and myocardial injury, represented by BNP and hsTnI values, would contribute to prioritization of LT candidates and help administer target therapies that could modify early mortality.

Who are at high risk of mortality and morbidity among children with congenital heart disease undergoing noncardiac surgery?

With advances in the development of surgical and medical treatments for congenital heart disease (CHD), the population of children and adults with CHD is growing. This population requires multiple surgical and diagnostic imaging procedures. Therefore, general anesthesia is inevitable. In many studies, it has been reported that children with CHD have increased anesthesia risks when undergoing noncardiac surgeries compared to children without CHD. The highest risk group included patients with functional single ventricle, suprasystemic pulmonary hypertension, left ventricular outflow obstruction, and cardiomyopathy. In this review, we provide an overview of perioperative risks in children with CHD undergoing noncardiac surgeries and anesthetic considerations in patients classified as having the highest risk.

Preoperative high-sensitivity troponin I and B-type natriuretic peptide, alone and in combination, for risk stratification of mortality after liver transplantation / 대한마취과학회지

Background@#Given the severe shortage of donor liver grafts, coupled with growing proportion of cardiovascular death after liver transplantation (LT), precise cardiovascular risk assessment is pivotal for selecting recipients who gain the greatest survival benefit from LT surgery. We aimed to determine the prognostic value of pre-LT combined measurement of B-type natriuretic peptide (BNP) and high-sensitivity troponin I (hsTnI) in predicting early post-LT mortality. @*Methods@#We retrospectively evaluated 2,490 consecutive adult LT patients between 2010 and 2018. Cut-off values of BNP and hsTnI for predicting post-LT 90-day mortality were calculated. According to the derived cut-off values of two cardiac biomarkers, alone and in combination, adjusted hazard ratios (aHR) of post-LT 90-day mortality were determined using multivariate Cox regression analysis. @*Results@#Mortality rate after 90 days was 2.9% (72/2,490). Rounded cut-off values for post-LT 90-day mortality were 400 pg/ml for BNP (aHR 2.02 [1.15, 3.52], P = 0.014) and 60 ng/L for hsTnI (aHR 2.65 [1.48, 4.74], P = 0.001), respectively. Among 273 patients with BNP ≥ 400 pg/ml, 50.9% of patients were further stratified into having hsTnI ≥ 60 ng/L. Combined use of pre-LT cardiac biomarkers predicted post-LT 90-day mortality rate; both non-elevated: 1.0% (21/2,084), either one is elevated: 9.0% (24/267), and both elevated: 19.4% (27/139, log-rank P < 0.001; aHR vs non-elevated 4.23 [1.98, 9.03], P < 0.001). @*Conclusions@#Concomitant elevation of both cardiac biomarkers posed significantly higher risk of 90-day mortality after LT. Pre-LT assessment cardiac strain and myocardial injury, represented by BNP and hsTnI values, would contribute to prioritization of LT candidates and help administer target therapies that could modify early mortality.

Ultrasound-Guided Percutaneous Release of the Trigger Thumb

PURPOSE: Trigger thumb is a common condition with a prevalence rate up to 3% among the adults. The main pathophysiology is locking of the flexor tendon at the A1 pulley. Treatments include nonsteroidal anti-inflammatory drug, steroid injection, and surgical A1 pulley release. The purpose of this study was to evaluate the safety and effectiveness of ultrasound-guided percutaneous release of trigger thumb. METHODS: The author prospectively reviewed 37 patients who had undergone ultrasound-guided percutaneous release by the same surgeon from January 2012 to June 2014. The effect of ultrasound-guided A1 pulley release was evaluated by using visual analogue scale (VAS) score, disabilities of arm, shoulder, and hand (DASH) score, and grip and pinch strengths preoperatively and at 12weeks after the surgery. In addition, complications related with the procedure were evaluated. RESULTS: Triggering and locking were resolved in all patients after surgery. VAS and DASH improved from 5.0±1.8 and 45.8±16.9 preoperatively to 0.3±0.6 and 16.2±6.3 at 12 weeks, respectively (p=0.019 and p=0.021). Grip and pinch strengths statistically improved from33.5±8.6 kg and 36.7±8.1 kg, preoperatively 46.2±6.1 kg and 47.1±7.4 kg, respectively (p=0.026 and p=0.041). Complications such as incomplete resection, neurologic symptoms or wound infection were not found throughout the period of the study. CONCLUSION: Ultrasound-guided percutaneous A1 pulley release provides complete relief of symptoms with no major complication in trigger thumb.

Usefulness of intraoperative bronchoscopy during surgical repair of a congenital cardiac anomaly with possible airway obstruction: three cases report / 대한마취과학회지

Compression of the airway is relatively common in pediatric patients, although it is often an unrecognized complication of congenital cardiac and aortic arch anomalies. Aortopexy has been established as a surgical treatment for tracheobronchial obstruction associated with vascular anomaly, aortic arch anomaly, esophageal atresia, and tracheoesophageal fistula. The tissue-to-tissue arch repair technique could result in severe airway complication such as compression of the left main bronchus which was not a problem before the correction. We report three cases of corrective open heart surgery monitored by intraoperative bronchoscopy performed during prebypass, and performed immediately before weaning from bypass, to evaluate tracheobronchial obstruction caused by congenital, complex cardiac anomalies in the operating room.

Anesthetic management for separation of thoracopagus twins with complex congenital heart disease: a case report / 대한마취과학회지

Although thoracopagus twins joined at the upper chest are the most common type of conjoined twins, the separation surgery in these cases has a higher mortality rate. Here, we describe an anesthetic management approach for the separation of thoracopagus conjoined twins sharing parts of a congenitally defective heart and liver. We emphasize the importance of vigilant intraoperative hemodynamic monitoring for early detection of unexpected events. Specifically, real-time continuous monitoring of cerebral oximetry using near-infrared spectroscopy allowed us to promptly detect cardiac arrest and hemodynamic deterioration.

Hemolysis of irradiated leukoreduced red blood cells during rapid warming: An in vitro experimental study

BACKGROUND: Although water chambers are often used as surrogate blood-warming devices to facilitate rapid warming of red blood cells (RBCs), these cells may be damaged if overheated. Moreover, filtered and irradiated RBCs may be damaged during the warming process, resulting in excessive hemolysis and extracellular potassium release. METHODS: Using hand-held syringes, each unit of irradiated and leukocyte-filtered RBCs was rapidly passed through a water chamber set to different temperatures (baseline before blood warming, 50℃, 60℃, and 70℃). The resulting plasma potassium and free hemoglobin levels were then measured. RESULTS: Warming RBCs to 60℃ and 70℃ induced significant increases in free hemoglobin (median [interquartile ranges] = 60.5 mg/dl [34.9-101.4] and 570.2 mg/dl [115.6-2289.7], respectively). Potassium levels after warming to 70℃ (31.4 ± 7.6 mEq/L) were significantly higher compared with baseline (29.7 ± 7.1 mEq/L; P = 0.029). Potassium levels were significantly correlated with storage duration after warming to 50℃ and 60℃ (r = 0.450 and P = 0.001; r = 0.351 and P = 0.015, respectively). CONCLUSIONS: Rapid warming of irradiated leukoreduced RBCs to 50℃ may not further increase the extracellular release of hemoglobin or potassium. However, irradiated leukoreduced RBCs that have been in storage for long periods of time and contain higher levels of potassium should be infused with caution.

Anesthetic Consideration for Neurointerventional Procedures / 신경중재치료의학

Interventional neuroradiology (INR) has been a rapidly expanding and advancing clinical area during the past few decades. As the complexity and diversity of INR procedures increases, the demand for anesthesia also increases. Anesthesia for interventional neuroradiology is a challenge for the anesthesiologist due to the unfamiliar working environment which the anesthesiologist must consider, as well as the unique neuro-interventional components. This review provides an overview of the anesthetic options and specific consideration of the anesthesia requirements for each procedure. We also introduce the anesthetic management for interventional neuroradiology performed in our medical institution.

A comparison of supraglottic airway i-gel(TM) vs. classic laryngeal mask airway in small children / 대한마취과학회지

BACKGROUND: i-gel(TM) is a new single-use supraglottic airway device without an inflatable cuff. This study was designed to compare the usefulness of i-gel(TM) versus a classic laryngeal mask airway (cLMA) in small children. METHODS: Sixty-three children (age range : 4-72 months) were randomly assigned to an i-gel(TM) or cLMA group. We evaluated hemodynamic data, airway sealing ability, the success rate of insertion, and adverse events including an inadvertent sliding out during ventilation. RESULTS: Demographic data and hemodynamic data obtained immediately after the insertion of these devices did not differ between the two groups. The success rates for insertion on the first attempt were 77 and 84% for i-gel(TM) and cLMA, respectively (P = 0.54), and the overall success rates were 87 and 100% respectively (P = 0.14). There were no significant differences in terms of airway leak pressure. The inserted i-gel(TM) inadvertently slid out in 8 of 31 patients but only one sliding out case occurred in the cLMA group (P = 0.02). There were no differences between the groups in terms of other side effects (e.g., coughing, bleeding) associated with the use of i-gel(TM) and cLMA (P = 0.75 and 0.49, respectively). CONCLUSIONS: Oropharyngeal leak pressure and insertion success rate of i-gel(TM) are similar to those of cLMA. However, i-gel(TM) is prone to inadvertent sliding out of the mouth in small children. Therefore, it is recommended that the i-gel(TM) should be secured more tightly to avoid displacement of the device.

Central venous catheter-related superior vena cava syndrome following renal transplantation: A case report / 대한마취과학회지

A 55-year-old man with end-stage renal disease had severe left ventricular dysfunction and a history of deep vein thrombosis. He underwent renal transplantation, during which a central venous catheter was inserted into the right jugular vein. The central venous pressure (CVP) exceeded 20 mmHg throughout the operation but there was no other adverse event. After surgery, although the left ventricular dysfunction improved, the CVP remained high. On postoperative day 10, the patient presented with cyanosis of the arms and redness of the face and was diagnosed with superior vena cava (SVC) syndrome, for which he underwent emergency thrombectomy and SVC reconstruction. The clinical course of this patient suggests that his end-stage renal disease-associated hypercoagulable state may have promoted thrombus formation. Moreover, placing the central venous catheter tip too deep may have encouraged thrombus formation. Repositioning the tip may have prevented this complication.

Spectral analysis of respiratory-related hemodynamic variables in simulated hypovolemia: a study in healthy volunteers with spontaneous breathing using a paced breathing activity / 대한마취과학회지

BACKGROUND: A dynamic preload index such as stroke volume variation (SVV) is not as reliable in spontaneous breathing (SB) patients as in mechanically ventilated patients. This study examined the hypothesis that spectral analysis of hemodynamic variables during paced breathing (PB) activity may be a feasible index of volume changes and fluid responsiveness, despite insufficient respiratory changes in the preload index during SB activity. METHODS: Blood pressure and stroke volume (SV) were measured in 16 subjects undergoing PB (15 breaths/min), using a Finometer device and the Modelflow method. Respiratory systolic pressure variation (SPV) and SVV were measured and respiratory frequency (RF, 0.2-0.3 Hz) of power spectra of SPV (SPV(RF)) and SVV (SVV(RF)) were computed using fast Fourier transformation. Progressive hypovolemia was simulated with lower body negative pressure (LBNP). Volume challenges were produced by infusion of normal saline and subsequent release of LBNP to baseline. Fluid responsiveness, defined as a >20% increase in SV, was assessed by the area under the curve (AUC) of receiver operating characteristic curves. RESULTS: Graded hypovolemia caused a significant increase in SPV(RF) and a decrease in SVV(RF). During volume expansion, SPV(RF) decreased and SVV(RF) rose significantly. Fluid responsiveness was better predicted with SVV(RF) (AUC 0.75) than with SPV(RF), SPV, or SVV. SVV(RF) before volume challenge was significantly correlated with volume expansion-induced changes in SV (r = -0.64). CONCLUSIONS: These results suggest that RF spectral analysis of dynamic preload variables may enable the detection of volume change and fluid responsiveness in SB hypovolemic patients performing PB activity.

Pneumomediastinum due to inadvertent bladder perforation during transurethral resection of the prostate : A case report / 대한마취과학회지

Transurethral resection of the prostate (TURP) is a common procedure for managing benign prostatic hyperplasia (BPH), and this procedure is associated with low complication rates. Bladder perforation is an unusual complication of TURP, and it may create an air leak into the retroperitoneal space. Here we describe a case of pneumomediastinum, pneumoretroperitoneum and subcutaneous emphysema that were all due to a bladder perforation that occurred during performing TURP in a 74-year-old male patient with BPH.

Effects of magnesium infusion on hemodynamic and autonomic changes in healthy volunteers / 대한마취과학회지

BACKGROUND: Magnesium has been used for treatments and preventions of various situations, such as cardiovascular disease and pre-eclampsia. And it also used for decreasing demands of anesthetics and analgesics during anesthesia. Activity of autonomic nervous system has important roles for homeostasis of cardiovascular system, and its dysfunction affects mortality and morbidity. Because there are few reports about effects of magnesium infusion on autonomic nervous system, we investigated effects of magnesium infusion on hemodynamic and autonomic changes using variable autonomic function tests in healthy volunteers. METHODS: Hemodynamic parameters, heart rate variability, blood pressure variability, and baroreflex sensitivity were evaluated before and after magnesium infusion of 30 mg/kg during 20 min in twenty healthy volunteers. Cold face test, valsalva maneuver were also performed before and after magnesium infusion. RESULTS: Low-frequency components of blood pressure variability decreased after magnesium infusion (P = 0.026). There were no significant differences in blood pressure, heart rate, cardiac output, stroke volume, total peripheral resistance, heart rate variablility and baroreflex sensitivity between before and after magnesium infusion. Increases of diastolic blood pressure during cold face test decreased significantly after magnesium infusion (P = 0.022). In addition, no significant hemodynamic and autonomic changes were found during valsalva maneuver. CONCLUSIONS: Central sympathetic vasomotor tone decreased after magnesium infusion of 30 mg/kg during 20 min in healthy volunteers. However, it had no effects on parasympathetic system and baroreflex sensitivity.

Influence of Anesthesia Induction with Ketamine on Baroreflex Control of Heart Rate / 대한마취과학회지

BACKGROUND: It is reported that ketamine increases central sympathetic activity as well as catecholamine reuptake inhibition. However, little has been known about baroreflex control of heart rate in ketamine anesthetized humans. Thus, the aim of this study was to analyze the effect of ketamine on spontaneous baroreflex sensitivity (BRS) during ketamine induction of anesthesia. METHODS: Beat-by-beat arterial blood pressure and electrocardiogram at 5 min before and 10 min after ketamine administration (2 mg/kg) were recorded in twenty healthy living liver transplant donors. Spontaneous BRS was assessed by sequence method and transfer function analysis method. RESULTS: Spontaneous BRS assessed by sequence method, BRSsequence, decreased from 13.7 +/- 6.3 to 7.8 +/- 4.5 ms/mmHg (P < 0.001). Spontaneous BRS assessed by low frequency transfer function method decreased from 10.9 +/- 5.4 to 7.0 +/- 4.1 ms/mmHg and by high frequency transfer function method from 14.8 +/- 9.2 to 8.7 +/- 8.8 ms/mmHg, respectively (P < 0.05). CONCLUSIONS: The spontaneous BRS was decreased during ketamine induction of general anesthesia. These results suggest that anesthesia induction with ketamine impairs baroreflex control of heart rate, which may provoke hemodynamic instability.

Massive Carbon Dioxide Embolism during the Minimally Invasive Robot-assisted Cardiac Surgery: A case report / 대한마취과학회지

A 37-year-old female was scheduled for minimally invasive mitral valve replacement and Maze operation using the robotically controlled camera (AESOP 3000, Computermotion(R), USA). Thoracic incision and carbon dioxide insufflation was started. The end tidal carbon dioxide suddenly decreased with hypotension and an increase in central venous pressure to 70 mmHg. Then, cardiopulmonary bypass was started and large amount of gas was aspirated. Carbon dioxide embolism was suspected, carbon dioxide insufflation was discontinued. The aspiration of carbon dioxide embolus from cannulae for cardiopulmonary bypass confirmed our diagnosis. The gas flowed out from the peritoneal cavity following diaphragmatic incision, we suspected that the insufflating needle was placed into peritoneal cavity. The operation was completed uneventfully. No neurologic and cardiopulmonary sequelae were noted. We experienced a case of carbon dioxide embolism incidentally induced by carbon dioxide insufflation into closed intraperitoneal cavity.

Hemodynamic Profile of Carotid Sinus Nerve Blockade on Hypotension Occurred Immediately after Carotid Endarterectomy Declamping: A case report / 대한마취과학회지

Carotid sinus nerve blockade (CSNB) has been shown to be effective for management of post-carotid endarterectomy (CEA) hypotension. The underlying hemodynamic changes are unknown. We retrospectively analyzed a recorded arterial blood pressure (ABP) waveform using a Modelflow technique. After declamping, total peripheral resistance (TPR) decreased (-65% of predeclamping value), but cardiac output (CO) and stroke volume (SV) increased (+60 and +57% of predeclamping value, respectively). CSNB abruptly increased blood pressure (BP) and TPR (75 and 95% of nadir, respectively), while CO and SV gradually decreased to -21 and -16% of maximum value, respectively). In conclusion, we found that severe decline of TPR was a cause of severe hypotension after declamping and CSNB increased BP mainly through increase in TPR, with little change in CO and SV.

Effects of Fresh Gas Flow Rate on the Ratio of Expired to Inspired Anesthetic Concentration / 대한마취과학회지

BACKGROUND: One way to make rapid increase in alveolar anesthetic concentration includes using high fresh gas flow rates. Fresh gas flow rates should be increased to compensate the amount of uptake either. This study was performed to elucidate optimal fresh gas flow rates for rapid induction by comparison of changes of ratio of expired to inspired concentration. METHODS: The study population was composed of 107 patients undergoing thyroidectomy. Patients were randomly allocated to one of three groups who received desflurane or sevoflurane or isoflurane. Each group was randomly subdivided into three groups who received one of the fresh gas flow rate: 2, 5 or 10 L/min. Inspired anesthetic concentration (Fi) and expiratory anesthetic concentration (Fe), delivered concentration (FD) were recorded. RESULTS: With same fresh gas flow rates, there were significant differences between Fe/Fi of desflurane, sevoflurane, isoflurane. With same anesthetics, Fe/Fi of desflurane and sevoflurane were not influenced by fresh gas flow rates. But Fe/Fi of isoflurane at 2 L/min was significantly lower than 5 L/min and 10 L/min. Fi/FD of desflurane at 10 L/min did not differ from sevoflurane. At 2 L/min and 5 L/min, Fi/FD of desflurane was highest and then sevofluane, isoflurane in that order. CONCLUSIONS: Because rates of Fe/Fi of desflurane and sevoflurane were not influenced by fresh gas flow rates, 2 L/min of fresh gas flow rates could be selected. However, considering the wash-in time in circuit, optimal choice of fresh gas flow rate for desflurane and sevoflurane could be 5 L/min, that of isoflurane be 10 L/min.

Assessment of the Mechanism of Arterial Blood Pressure Change during Sevoflurane Induction: Beat-to-Beat Analysis of Hemodynamic Variables Using a Modelflow Method / 대한마취과학회지

BACKGROUND: A modelflow method provides beat-to-beat analysis of cardiovascular variables based on arterial pulse pressure analysis. In this study, we assessed the mechanism of arterial blood pressure (ABP) change during sevoflurane induction by the analysis of beat-to-beat hemodynamic changes using a modelflow method. METHODS: Beat-to-beat ABP was measured during a stable conscious state (baseline) and vital capacity induction with sevoflurane 6 vol% and oxygen 8 L/min in 18 healthy living liver transplant donors. Alterations of beat-to-beat systolic ABP, mean ABP, diastolic ABP, heart rate (HR), stroke volume (SV), cardiac output (CO), and total peripheral resistance (TPR) by sevoflurane induction were estimated noninvasively using a modelflow method simulating aortic input impedance from an ABP waveform. RESULTS: After sevoflurane induction, ABP, SV, CO, and TPR decreased significantly (all P < 0.05), but HR did not change significantly. After tracheal intubation, ABP, CO, and TPR did not change significantly compared with baseline, but HR increased and SV decreased significantly (both P < 0.05). CONCLUSIONS: Using a modelflow beat-to-beat analysis of cardiovascular variables, we found that ABP did not change significantly compared to baseline after tracheal intubation during sevoflurane induction, indicating the counteraction of increased HR and decreased SV, and that the reduction of SV by tracheal intubation suggests the suppression by increased HR and TPR compared with that after sevoflurane induction.

Assessment of Cardiovascular Autonomic Function in Patients with Liver Cirrhosis Using Heart Rate Variability, Blood Pressure Variability and Baroreflex Sensitivity / 대한마취과학회지

BACKGROUND: Liver cirrhosis is associated with several hemodynamic abnormalities, including an impairment of autonomic nervous system reflexes, but very few have compared the disease severity with cardiovascular autonomic dysfunction assessed by spectral analysis of blood pressure and electrocardiogram. The aim of this study was to investigate the relationship between Child-Turcotte-Pugh (CTP) score and autonomic indices in patients with liver cirrhosis using the heart rate variability (HRV), blood pressure variability (BPV) and baroreflex sensitivity (BRS). METHODS: Fifty patients scheduled for liver transplantation recipients under general anesthesia were enrolled in the study. Beat-to-beat blood pressure and RR interval were measured for five minutes before anesthesia induction. HRV and BPV were estimated by power spectral analysis of RR interval and systolic blood pressure. BRS was estimated by both the sequence method (Sequence BRS) and high frequency (HF) gain of transfer function analysis (HF BRS). RESULTS: Significant inverse correlations between CTP score and Sequence BRS (r = -0.61), HF BRS (r = -0.59), low frequency (LF) and HF power of HRV (r = -0.57, r = -0.46), LF power of BPV (r = -0.37) were found. However, no significant correlations were observed between CTP score and LF/HF ratio of HRV (r = -0.02) and HF power of BPV (r = 0.27). CONCLUSIONS: These results showed that autonomic dysfunction assessed by spectral analysis was associated with increasing severity of liver cirrhosis. Further study will be needed to clarify relationship between our findings and hemodynamic fluctuations during anesthesia for liver transplantation.

Change of Blood Pressure Variability before and during Sevoflurane Anesthesia / 대한마취과학회지

BACKGROUND: Relatively little is known about the effects of general anesthesia on blood pressure variability (BPV). This study was designed to evaluate the changes of high frequency (HF) and low frequency (LF) of BPV before and during general anesthesia with sevoflurane. METHODS: Beat-to-beat blood pressure was recorded at conscious baseline and during general anesthesia at 2% end-tidal sevoflurane in 17 healthy living-liver transplantation donors. BPV estimated by power spectra of systolic (SBP) and mean blood pressure (MBP) was calculated. RESULTS: Both LF power of SBP and MBP were diminished to 96.2% and 97.1% during sevoflurane anesthesia (5.5 +/- 2.8 to 0.2 +/- 0.2 mmHg2, 6.6 +/- 3.7 to 0.2 +/- 0.2 mmHg2, P < 0.001 for both). However, there were no significant changes of HF power of SBP and MBP during sevoflurane anesthesia. CONCLUSION: Sevoflurane anesthesia reduced noticeably LF power, which was associated with sympathetic vasomotor activity, but not HF power, which represents mostly the mechanical effect of respiration on blood pressure, of BPV.