The Effect of Intrathecal Morphine on Postoperative Opioid Consumption in Patients Undergoing Abdominal Surgery for Gynecologic Malignancy: A Randomized Sham-Controlled Trial.

BACKGROUND: Surgery for gynecologic malignancy via midline-laparotomy leads to severe postoperative pain. Adequate pain control while sparing opioid consumption does offer benefits in postoperative complications and recovery. Intrathecal morphine (ITM) provides simple and effective analgesia. In this randomized trial, we compared postoperative opioid consumption in patients who received either ITM or a sham procedure. METHODS: We enrolled 68 adult patients undergoing open gynecologic oncology surgery from June 2021 to November 2021. They were randomly allocated to the ITM group (ITM; 200 µg injection) or sham group (sham procedure) to achieve a final 1:1 ratio between groups. We compared opioid consumption and pain severity during 72 hours after surgery. The variables regarding postoperative recovery and patient-centered outcomes were collected. The primary outcome is cumulative intravenous (IV) opioid consumption 24 hours after surgery. RESULTS: The median (interquartile range) cumulative IV opioid consumption during 24 hours after surgery was 18 mg (12-29) in the ITM group and 36 mg (27-42) in the sham group (median difference, 13; 95% confidence interval, 7.2-20.7; P < .001). Patient satisfaction regarding pain control was statistically significantly higher in the ITM group than in the sham group at postoperative 24 and 48 hours ( P < .001 and P = .005, respectively). There were no significant differences in the variables associated with postoperative recovery and frequency of complications requiring treatment. CONCLUSIONS: ITM is a safe and effective analgesic method after curative intent laparotomy for gynecologic malignancy. ITM provides better pain relief, reduces opioid consumption, and improves patient satisfaction without additional evident adverse events.

The angle range of leg abduction with external hip rotation which can minimize femoral artery and vein overlap in pediatric patients.

BACKGROUND: Since the femoral artery frequently overlaps the femoral vein, femoral central venous catheterization carries the risk of arterial puncture in pediatric patients. AIMS: We evaluated the angle range of leg abduction with external hip rotation to minimize the overlap between the femoral artery and vein in pediatric patients undergoing general anesthesia. METHODS: Eighty-two pediatric patients who underwent elective surgery with general anesthesia were enrolled in this study. Using ultrasonography, patients were divided into groups N (patients with non-overlap) and O (patients with continuing overlap) based on the presence of non-overlap range between the femoral artery and vein. The range minimizing the overlap was defined as the range without overlap in group N and as the range presenting the overlap that was less-than-half of the radius of the femoral vein in group O. By increasing the angle of leg abduction with external hip rotation, the starting and ending angles minimizing the overlap were found using ultrasonographic images. RESULTS: The angle range of leg abduction with external hip rotation minimizing the overlap between the femoral artery and vein was defined as the range from the maximum 99% confidence interval of starting angles to the minimum 99% confidence interval of ending angles, which was between 45° and 65° in group N and between 48° and 58° in group O, respectively. CONCLUSION: Positioning patients in a range of 48° and 58° leg abduction with external hip rotation can minimize the overlap between the femoral artery and vein. However, the clinical usefulness of this positioning for femoral venous catheterization remains to be seen.

Predictive Value of Intraoperative Thromboelastometry for the Risk of Perioperative Excessive Blood Loss in Infants and Children Undergoing Congenital Cardiac Surgery: A Retrospective Analysis.

OBJECTIVE: Laboratory hemostatic variables and parameters of rotational thromboelastometry (ROTEM) were evaluated for their ability to predict perioperative excessive blood loss (PEBL) after congenital cardiac surgery. DESIGN: Retrospective and observational. SETTING: Single, large university hospital. PARTICIPANTS: The study comprised 119 children younger than 10 years old undergoing congenital cardiac surgery with cardiopulmonary bypass (CPB). MEASUREMENTS AND MAIN RESULTS: Intraoperative excessive blood loss was defined as estimated blood loss≥50% of estimated blood volume (EBV). Postoperative excessive blood loss was defined as measured postoperative chest tube and Jackson-Pratt drainage≥30% of EBV over 12 hours or≥50% of EBV over 24 hours in the intensive care unit. PEBL was defined as either intraoperative or postoperative excessive blood loss. External temogram (EXTEM) and fibrinogen temogram (FIBTEM) were analyzed before and after CPB with ROTEM and laboratory hemostatic variables. Multivariate logistic regression was performed. Incidence of PEBL was 19.3% (n = 23). Independent risk factors for PEBL were CPB time>120 minutes, post-CPB FIBTEM alpha-angle, clot firmness after 10 minutes<5 mm, post-CPB EXTEM alpha-angle, clot firmness after 10 minutes<30 mm, and post-CPB EXTEM maximal lysis>20%. Laboratory hemostatic variables were not significant in multivariate analysis. The risk prediction model was developed from the results of multivariate analysis. The area under the receiver operating characteristic curve was 0.94 (95% confidence interval: 0.90-0.99). CONCLUSIONS: Post-CPB ROTEM may be useful for predicting both intraoperative and postoperative excessive blood loss in congenital cardiac surgery. This study provided an accurate prediction model for PEBL and supported intraoperative transfusion guidance using post-CPB FIBTEM-A10 and EXTEM-A10.

Fibrinogen recovery and changes in fibrin-based clot firmness after cryoprecipitate administration in patients undergoing aortic surgery involving deep hypothermic circulatory arrest.

BACKGROUND: Cryoprecipitate may be used to treat bleeding in cardiac surgery. Its effects on plasma fibrinogen and fibrin clotting in this setting are poorly defined. STUDY DESIGN AND METHODS: Patients undergoing on-pump aortic surgery with deep hypothermic circulatory arrest (DHCA) were recruited prospectively. After protamine reversal, cryoprecipitate was administered to patients with bleeding, and fibrin deficit was indicated by thromboelastometry (ROTEM)-based FIBTEM test. Coagulation was assessed using ROTEM-based tests and standard laboratory tests before and after cryoprecipitate. RESULTS: Thirteen patients were included. Cryoprecipitate significantly elevated EXTEM A10 from (mean ± standard deviation) 29.4 ± 5.8 to 34.8 ± 5.9 mm (p = 0.01), FIBTEM A10 from 3.5 ± 0.9 to 5.8 ± 1.7 mm (p = 0.04), and plasma fibrinogen concentration from 154.2 ± 25.6 to 193.4 ± 30.5 mg/dL (p = 0.01). EXTEM clot elasticity at 10 minutes (CE10) increased from 42.5 ± 12.0 to 54.7 ± 14.9 mm after cryoprecipitate (30.0% increase). FIBTEM CE10 increased from 3.7 ± 0.9 to 6.2 ± 2.0 mm (53.0% increase). A fibrinogen dose of 13.2 ± 5.2 mg/kg was required to increase FIBTEM A10 by 1 mm. In vivo recovery of fibrinogen was 61.6 ± 31.2%. CONCLUSIONS: Cryoprecipitate increased plasma fibrinogen levels and fibrin-based clotting in bleeding patients undergoing aortic surgery with DHCA. In vivo recovery of fibrinogen was considerably below 100% and fibrinogen content varied between cryoprecipitate units. Trials are needed to assess whether cryoprecipitate impacts clinical outcomes and to evaluate its safety.

Preoperative C-reactive protein/albumin ratio and mortality of off-pump coronary artery bypass graft.

Background: We sought to investigate the prognostic value of preoperative C-reactive protein (CRP)-to-albumin ratio (CAR) for the prediction of mortality in patients undergoing off-pump coronary artery bypass grafting (OPCAB). Methods: From January 2010 to August 2016, adult patients undergoing OPCAB were analyzed retrospectively. In a total of 2,082 patients, preoperative inflammatory markers including CAR, CRP, neutrophil-to-lymphocyte ratio, and platelet-to-lymphocyte ratio were recorded. Receiver operating characteristic (ROC) curves were used to determine the optimal threshold and compare the predictive values of the markers. The patients were divided into two groups according to the cut-off value of CAR, and then the outcomes were compared. The primary end point was 1-year mortality. Results: During the 1-year follow-up period, 25 patients (1.2%) died after OPCAB. The area under the curve of CAR for 1-year mortality was 0.767, which was significantly higher than other inflammatory markers. According to the calculated cut-off value of 1.326, the patients were divided into two groups: 1,580 (75.9%) patients were placed in the low CAR group vs. 502 (24.1%) patients in the high CAR group. After adjustment with inverse probability weighting, high CAR was significantly associated with increased risk of 1-year mortality after OPCAB (Hazard ratio, 5.01; 95% Confidence interval, 2.01-12.50; p < 0.001). Conclusions: In this study, we demonstrated that preoperative CAR was associated with 1-year mortality following OPCAB. Compared to previous inflammatory markers, CAR may offer superior predictive power for mortality in patients undergoing OPCAB. For validation of our findings, further prospective studies are needed.

Initial experience with the enhanced recovery after surgery (ERAS) protocols in gynecologic surgery at an urban academic tertiary medical center.

Background: The enhanced recovery after surgery (ERAS) protocols have been consistently associated with improved patient experience and surgical outcomes. Despite the release of ERAS Society guidelines specific to gynecologic oncology, the adoption of ERAS in gynecology on global level has been disappointingly low and some centers have shown minimal improvement in clinical outcomes after adopting ERAS. The aim of this study is to describe the development and early experience of ERAS protocols in gynecologic surgery at an urban academic tertiary medical center. Methods: This was an observational prospective cohort study. The target patient population included those with low comorbidities who were scheduled to undergo various types of gynecologic surgeries for both benign and malignant diseases between October 2020 and February 2021. Two attending surgeons implemented the protocols for their patients (ERAS cohort) while three attending surgeons maintained the conventional perioperative care for their patients (non-ERAS cohort). Baseline characteristics, surgical outcomes and patients' answers to a 12-question survey were compared. A case-matched comparative analysis was also performed between the ERAS cohort and the historical non-ERAS cohort (those who received the same types of surgical procedures from the two ERAS attending surgeons prior to the implementation of the protocols). Results: A total of 244 patients were evaluated (122 in the ERAS cohort vs. 122 in the non-ERAS cohort). The number of vials of opioid analgesia used during the first two postoperative days was significantly lower whereas the use of nonsteroidal anti-inflammatory drugs (NSAIDs) and acetaminophen was more frequent in the ERAS cohort group. The patients in the ERAS group reported less postoperative pain, feelings of hunger and thirst, and greater amount of exercise postoperatively. These benefits of the ERAS cohort were more pronounced in the patients who underwent laparotomic surgeries than those who underwent laparoscopic surgeries. The case-matched comparative analysis also showed similar results. The length of hospital stay did not differ between those who underwent the ERAS protocols and those who did not. Conclusions: The results of the study demonstrated the safety, clinical feasibility and benefits of the ERAS protocols for patients undergoing gynecologic surgeries for both benign and malignant indications.

The effect of passive leg elevation and/or trendelenburg position on the cross-sectional area of the internal jugular vein in infants and young children undergoing surgery for congenital heart disease.

BACKGROUND: In this study we evaluated the effect of passive leg elevation (LE) and Trendelenburg (T) position on the cross-sectional area (CSA) of the internal jugular vein (IJV) in infants and young children undergoing surgery for congenital heart disease. A secondary aim was to compare the CSA of the IJV between subjects with right-to-left (RL) shunt and left-to-right (LR) shunt. METHODS: Ninety infants and small children from 10 days to 31 months old weighing from 1.5 to 9.7 kg were assigned to group RL (n = 48) or LR (n = 42). In both groups, the CSA, transverse, and vertical diameters of the IJV on both sides of the neck were measured using a 2-dimensional ultrasound transducer in the following positions: supine position, 15° of T position, supine position with 50° of LE, and 15° of Trendelenburg position with 50° of LE (TLE). A more than 25% increase in mean CSA of the IJV was considered clinically significant. RESULTS: In group LR, T, LE, and TLE significantly increased CSA of both right (at least 12.3%, 10.3%, and 18.3%, respectively, "at least" refers to the lower 95% confidence limits) and left (at least 15.8%, 15.0%, and 18.9%, respectively) IJVs, whereas only TLE increased the CSA of both IJVs significantly in group RL (at least 8.2% and 7.7% in the right and left, respectively). The increase in the CSA of the right IJV related to T and TLE was larger in group LR than in group RL (at least 12.3% vs 1.2% for T and at least 18.3% vs 8.2% for TLE, respectively). A clinically significant increase in CSA was achieved in both right and left IJVs with TLE in group LR (mean 28.6% and 26.3%, respectively). The CSA of the right IJV was larger than that of the left IJV in most (at least 69.2%) patients. CONCLUSIONS: Passive LE was as effective as T position to increase the CSA of the IJV, but there was no clinically significant increase in the CSA with any single maneuver. Only T position with passive LE achieved a clinically significant increase in the CSA of both IJVs in infants and young children with LR shunt, but not in the same age group with RL shunt.

Simplified clinical risk score to predict acute kidney injury after aortic surgery.

OBJECTIVE: The authors identified risk factors for acute kidney injury (AKI) defined by risk, injury, failure, loss, end-stage (RIFLE) criteria after aortic surgery with cardiopulmonary bypass and constructed a simplified risk score for the prediction of AKI. DESIGN: Retrospective and observational. SETTING: Single large university hospital. PARTICIPANTS: Patients (737) who underwent aortic surgery with cardiopulmonary bypass between 1997 and 2010. MAIN RESULTS: Multivariate logistic regression analysis was used to evaluate risk factors. A scoring model was developed in a randomly selected derivation cohort (n = 417), and was validated on the remaining patients. The scoring model was developed with a score based on regression ß-coefficient, and was compared with previous indices as measured by the area under the receiver operating characteristic curve (AUC). The incidence of AKI was 29.0%, and 5.8% required renal replacement therapy. Independent risk factors for AKI were age older than 60 years, preoperative glomerular filtration rate <60 mL/min/1.73 m(2), left ventricular ejection fraction <55%, operation time >7 hours, intraoperative urine output <0.5 mL/kg/h, and intraoperative furosemide use. The authors made a score by weighting them at 1 point each. The risk score was valid in predicting AKI, and the AUC was 0.74 [95% confidence interval (CI): 0.69 to 0.79], which was similar to that in the validation cohort: 0.74 (95% CI: 0.69 to 0.80; p = 0.97). The risk-scoring model showed a better performance compared with previously reported indices. CONCLUSIONS: The model would provide a simplified clinical score stratifying the risk of postoperative AKI in patients undergoing aortic surgery.

The effect of adding chewing gum to oral carbohydrates on preoperative anxiety scores in women undergoing gynecological surgery: A randomized controlled study.

BACKGROUND: Preoperative anxiety is an unpleasant experience that can adversely affect perioperative outcomes. Although clinical benefits of preoperative oral carbohydrate is well reported, the effect of adding chewing gum to carbohydrate loading has never been studied. We aimed to investigate the effect of adding gum-chewing to oral carbohydrates on preoperative anxiety and gastric volume in patients undergoing gynecologic surgery. METHODS: One hundred and four patients were enrolled and randomized either into a carbohydrate drink group (CHD group) or CHD with gum group. The CHD group was instructed to drink 400 mL of oral carbohydrate the evening before and 200-400 mL 3 hours before surgery. The CHD with gum group was encouraged to chew gum freely during preanesthetic fasting in addition to consuming oral carbohydrates in the same manner. The primary endpoint was preoperative anxiety assessed using the Amsterdam preoperative anxiety and information scale (APAIS). The degree of patient-reported quality of recovery after surgery and gastric volume prior to general anesthesia were also compared as secondary outcomes. RESULTS: Preoperative APAIS was lower in the CHD with gum group compared with the CHD group (16 [11.5, 20] vs. 20 [16.5, 23], p = 0.008). Patient-rated quality of recovery after surgery was also higher in the CHD with gum group and showed a significant negative correlation with preoperative APAIS score (correlation coefficient: -0.950, p = 0.001). Gastric volume were not different between the groups (0 [0-0.45] vs. 0 [0-0.22], p = 0.158). CONCLUSION: The addition of gum chewing to oral carbohydrate loading during preoperative fasting was more effective in relieving preoperative anxiety than oral carbohydrate alone in women patients undergoing elective gynecologic surgery. TRIAL REGISTRATION: Clinical Research Information Services, CRIS identifier: KCT0005714, https://cris.nih.go.kr/cris/index.jsp.

Effect of chewing gum on anxiety in women undergoing elective cesarean section: a randomized controlled study.

BACKGROUND: Preoperative anxiety is a common problem in pregnant women undergoing elective cesarean section. We aimed to determine the anxiolytic effects of chewing gum in pregnant women undergoing elective cesarean section under regional anesthesia. METHODS: This was a single-center, prospective, randomized controlled trial. Sixty-six women were randomly assigned to either the control group (n=33) or gum group (n=33) in a 1:1 ratio. In the gum group, the participants chewed xylitol gum for at least 10 min/h, regardless of fasting. Gum chewing was started at 5 pm a day before surgery and continued till the participant entered the operation room. In the control group, participants were requested to follow fasting guidelines without further instruction. The primary outcome was preoperative anxiety measured using the Amsterdam Preoperative Anxiety and Information Scale (APAIS) immediately before surgery. RESULTS: The APAIS score immediately before surgery showed no significant difference between the control and the gum group (19.2±5.8 vs. 19.1±4.1, P>0.99). There were no statistically significant differences in the eight items related to anxiety: unfitness, concentration difficulty, hunger, thirst, dry mouth, fatigue, headache, and nausea. However, the pain score during the procedure of combined spinal epidural anesthesia was significantly lower in the chewing gum group [4 (IQR, 3-5.5)] than in the control group [5 (IQR, 3-7), P=0.045]. CONCLUSIONS: Preoperative gum chewing did not reduce anxiety levels measured immediately before entering the operating room in the participants undergoing elective cesarean section. TRIAL REGISTRATION: Clinical Trial Registry of Korea: https://cris.nih.go.kr/cris/index.jsp and identifier: KCT0006602; date of registration: September 27, 2021; principal investigator's name: RyungA Kang.

Anxiolytic effects of chewing gum during preoperative fasting and patient-centered outcome in female patients undergoing elective gynecologic surgery: randomized controlled study.

Although previous studies reported that chewing gum during the preoperative fasting has the benefits of alleviating anxiety and dry mouth, preoperative chewing gum has yet to be accepted as a standard practice due to conventional anesthetic custom. Our study aimed to prospectively evaluate the effects of gum chewing on preoperative anxiety and patient's discomfort in female patients undergoing gynecologic surgery. Ninety-four patients were enrolled and randomized either into conventional fasting group (control group) or chewing gum with fasting group (gum group). The control group was instructed to fast from 3 p.m. on the day before surgery. The gum group performed preoperative fasting in the same manner, but was encouraged to chew gum freely during the fasting period. The primary endpoint was the degree of preoperative anxiety. For the evaluation of preoperative anxiety, Amsterdam preoperative anxiety and information scale (APAIS) was used. Preoperative gastric fluid volume and acidity were also measured as the secondary outcomes. Preoperative anxiety using APAIS was significantly lower in the gum group compared to the control group (control group vs. gum group: 20.9 vs. 17.8, p = 0.009). However, there was no significant difference in the gastric fluid analysis between the groups. In the female patients for elective gynecologic surgery, chewing gum during the preoperative fasting period helped to alleviate preoperative anxiety without additional increase of pulmonary aspiration risks.Trial registration: KCT0004422 (05/11/2019, https://cris.nih.go.kr ; registration number).

A comparison of the effects of preanesthetic administration of crystalloid versus colloid on intrathecal spread of isobaric spinal anesthetics and cerebrospinal fluid movement.

BACKGROUND: Movement of the cerebrospinal fluid (CSF) is one of the most important factors in determining the intrathecal spread of isobaric spinal anesthetics. Preanesthetic administration of either crystalloid or colloid immediately before spinal anesthesia (preload) may result in different CSF pulsatile movement because of their different physical properties. We examined whether preload of crystalloid versus colloid may have different effects on the intrathecal spread of isobaric spinal anesthetics as a result of their different CSF dynamics regarding its pulsatile movement. METHODS: In a clinical study of isobaric spinal anesthesia, patients were allocated into 1 of 2 groups according to preload with either crystalloid (n = 30) or colloid (n = 30) before spinal anesthesia with 0.5 isobaric tetracaine. The pulsatile movements of CSF at the L2-3 intervertebral space and midportion of the aqueduct of Sylvius were also examined by magnetic resonance images in healthy volunteers (n = 23) at 0, 30, and 60 minutes after administering either crystalloid or colloid. RESULTS: In the clinical study, the time to reach the peak sensory block level was delayed significantly in the crystalloid preload group (27.2 ± 17.8 minutes; P < 0.01) compared with the colloid preload group (13.9 ± 7.0 minutes). The median sensory block levels of the crystalloid preload group at 15 minutes (T10, P < 0.05) and 20 minutes (T9.5, P < 0.05) were significantly lower than those (T8, T7, respectively) of the colloid preload group. In the magnetic resonance imaging study, cranially directed CSF pulsatile movement decreased significantly at the L2-3 intervertebral intrathecal space at 30 minutes after crystalloid administration, but not after colloid administration. The CSF production rate significantly increased at 30 minutes (637 µL/min, P < 0.05) after crystalloid preload compared with the baseline measurement (448 µL/min), and then slightly decreased (609 µL/min) at 60 minutes. In the colloid preload group, the CSF production rate was not statistically significant compared with the baseline measurement (464, 512, and 542 µL/min at baseline, 30, and 60 minutes, respectively). CONCLUSIONS: Compared with a colloid preload, which may be comparable to the no-preload condition, crystalloid preload prolonged the time to reach the peak sensory block level in isobaric spinal anesthesia, which might have been caused by a significant decrease in CSF pulsatile movement. This attenuated CSF pulsatile movement in the crystalloid preload group might have resulted from significant increases of CSF production.

Downregulation of constitutive and cytokine-induced complement 3 expression by morphine in rat astrocytes.

BACKGROUND: The effect of opioids on inflammation and immune responses is an important subject of investigation because immunoregulatory cytokines are produced in the central nervous system and opioid receptors are widespread in these cells. OBJECTIVES: The aim of this study was to evaluate the immunomodulatory effect of morphine on the C3 expression (both constitutive and proinflammatory cytokine-induced C3 expression) in primary rat astrocytes. METHODS: Primary rat astrocytes were untreated or treated with morphine in different concentrations (10(-6) to 10(-2) M) before incubation without or with 5 U/mL tumor necrosis factor-α (TNF-α), and C3 protein and mRNA expressions were measured. Similarly, astrocytes were treated with 10(-3) M morphine and stimulated with other proinflammatory cytokines, including 10 ng/mL interleukin-8 (IL-8) and 5 U/mL IL-1ß. Astrocytes were exposed to 10(-5) M naloxone for 2 hours before adding morphine, and TNF-α and C3 protein was measured. Tumor growth factor-ß (TGF-ß) was measured from the supernatants of each proinflammatory cytokine. RESULTS: All results are expressed as mean percentages of C3 production by normalizing C3 without morphine or any cytokine treatment as 100%. Constitutive C3 protein production was decreased at morphine 10(-3) M (57.2%) and 10(-2) M (30.1%). Pretreatment with morphine suppressed induction of C3 expression at both the protein and mRNA levels in astrocytes stimulated with TNF-α, IL-8, and IL-1ß (P < 0.05) in a dose-dependent manner. The inhibition of C3 protein production by morphine (10(-3) M; 33%) was partially attenuated by naloxone (52.0%) (P < 0.05). The pretreatment of astrocytes with morphine (10(-3) M) before stimulation with TNF-α, IL-8, and IL-1ß increased by 33% (P < 0.05), decreased by 15.2% (P < 0.05), and did not change the production of TGF-ß protein, respectively. CONCLUSIONS: Morphine downregulated both constitutive and proinflammatory cytokine-induced C3 expression of astrocytes at the transcriptional level, but not in a cytokine-specific manner.

Efficacy of milrinone versus nitroglycerin in controlling pulmonary arterial hypertension induced by intravenous injections of absolute ethanol in anesthetized dogs.

PURPOSE: To compare the attenuating effects of milrinone versus nitroglycerin on pulmonary artery pressure (PAP) increase caused by repeat intravenous bolus injection of absolute ethanol in anesthetized dogs. MATERIALS AND METHODS: Twenty-four dogs were randomly distributed into three groups: a control group (group C), a nitroglycerin group (treated with a continuous infusion of nitroglycerin at 5.0 microg/kg/min; group N), and a milrinone group (treated with a continuous infusion of milrinone at 3.0 microg/kg/min after an initial bolus dose of 100 microg/kg; group M). Absolute ethanol (0.1 mL/kg) was injected at 10-minute intervals via a 5-F angiographic catheter advanced into the proximal portion of the inferior vena cava. Immediately before and after each intravenous injection of absolute ethanol, hemodynamic values were obtained through a pulmonary arterial catheter. RESULTS: Group M showed more stable hemodynamic values of systolic, mean, and diastolic PAP and pulmonary vascular resistance (PVR) compared with groups C and N. In addition, group M showed significantly higher values of cardiac output versus group C at 10 minutes after the 10th bolus of ethanol. After restoration of spontaneous breathing, group M also showed the least hemodynamic changes in systolic, mean, and diastolic PAPs and PVR among the groups. CONCLUSIONS: Although a continuous infusion of nitroglycerin or milrinone effectively prevented cardiovascular deterioration, milrinone was superior to nitroglycerin in managing the acute hemodynamic changes that resulted from repeated intravenous bolus injections of absolute ethanol (0.1 mL/kg) in healthy anesthetized dogs.

Effects of repeat bolus ethanol injections on cardiopulmonary hemodynamic changes during embolotherapy of arteriovenous malformations of the extremities.

PURPOSE: This study was designed to investigate the effects of repeat bolus absolute ethanol injections on cardiopulmonary hemodynamic changes during ethanol embolotherapy of inoperable congenital arteriovenous (AV) malformations in the extremities. MATERIALS AND METHODS: Thirty adult patients (14 male, 16 female; age range, 22-51 years) who underwent ethanol embolotherapy of extremity AV malformations were enrolled in the study. A pulmonary artery catheter was used to measure hemodynamic profiles at baseline (T(baseline)), immediately before (T(pre)) and after (T(post)) a bolus injection of absolute ethanol, at the time of the maximum mean pulmonary arterial pressure (PAP) value during a session (T(highest)), 10 minutes after the final injection (T(final)), and after restoration of spontaneous breathing (T(resp)). RESULTS: The systolic, mean, and diastolic PAP (P < .01, P < .01, and P < .01, respectively) and the systemic vascular resistance index (P < .05) and pulmonary vascular resistance index (PVRI; P < .05) of T(highest) and T(resp) were significantly higher than values for T(final). The volume of a single bolus injection of absolute ethanol from 0.023 to 0.175 mL/kg of body weight showed that the systolic PAP (P = .02), pulmonary capillary wedge pressure (P = .02), and PVRI (P < .01) significantly increased in accordance with the increased single volume of absolute ethanol. A significant increase of the right ventricular end-diastolic volume index and right ventricular end-systolic volume index were observed at a dose of more than 0.14 mL/kg of body weight for a single bolus injection of absolute ethanol. CONCLUSIONS: During ethanol embolotherapy of extremity AV malformations, significant hemodynamic changes can arise during a bolus injection of absolute ethanol. Cardiopulmonary hemodynamic profiles should be monitored closely after a bolus injection of more than 0.14 mL/kg of body weight of absolute ethanol.

Cardiovascular effects and predictability of cardiovascular collapse after repeated intravenous bolus injections of absolute ethanol in anesthetized pigs.

PURPOSE: To evaluate the effects of repeated intravenous bolus injections of absolute ethanol on cardiopulmonary hemodynamic changes and to investigate the predictability of ethanol-induced cardiovascular collapse in anesthetized pigs. MATERIALS AND METHODS: Twenty pigs aged 3-6 months and weighing 28-38 kg were enrolled in the study. Absolute ethanol (0.1 mL/kg of body weight) was repeatedly injected through the inferior vena cava central to the renal vein at 10-minute intervals up to a total volume of 1.0 mL/kg. The subjects were divided into a cardiovascular collapse group and a no-collapse group according to the development or absence of cardiac collapse. RESULTS: Among the 20 pigs, 12 died before the final injection. Hemodynamic parameters measured immediately before the injection of absolute ethanol did not differ between the cardiovascular collapse group and the no-collapse group except that among animals with cardiovascular collapse, the injection immediately before the one causing cardiovascular collapse resulted in significant increases in the following hemodynamic parameters: mean pulmonary arterial pressure (P < .01), pulmonary vascular resistance (P = .04), and right ventricular end-diastolic volume (P = .02). No such increases were observed in the no-collapse group. CONCLUSIONS: Hemodynamic profiles in pigs obtained immediately before intravenous injection of absolute ethanol did not predict the subsequent occurrence of cardiovascular collapse except after the injection immediately preceding the one resulting in cardiovascular collapse. In this animal model, significant increases in select hemodynamic parameters occurred after the injection immediately preceding the one resulting in cardiovascular collapse.

Intravascular injection in lumbar medial branch block: a prospective evaluation of 1433 injections.

BACKGROUND: The successful outcome and validity of lumbar medial branch block (MBB) are largely dependent on technique accuracy. Intravascular uptake of injectate causes a false-negative response to block and is associated with various possible complications. In the current study, we prospectively evaluated the incidence of, and the factors associated with, intravascular injection during block. In addition, we assessed the efficiencies of generally accepted safety measures, such as preinjection aspiration and intermittent fluoroscopy to avoid intravascular injections. METHODS: We prospectively examined 1433 lumbar MBBs in 456 patients performed by seven physicians. Aspiration test, spot radiography, and contrast injection under real-time fluoroscopic visualization were performed sequentially without repositioning the needle. Incidences of blood flashback and the presence of intravascular contrast spread on spot radiographic images and during real-time fluoroscopy were checked. The factors studied for intravascular injection included physician experience, patient age and sex, needle gauge, and block spinal level. RESULTS: No specific factors were found to affect the incidence of intravascular uptake during block. The overall incidence of intravascular uptake was 6.1% per nerve block (88/1433), and 30 of these were predicted by preinjection aspiration (sensitivity = 34.1%) and 52 by spot radiography (sensitivity = 59.1%). CONCLUSIONS: The aspiration test with or without spot radiography frequently missed the intravascular uptake of contrast during lumbar MBBs. We strongly advocate the use of real-time fluoroscopy during contrast injection to increase diagnostic and therapeutic value and to avoid possible complications.

The effects of prehydration on the properties of cerebrospinal fluid and the spread of isobaric spinal anesthetic drug.

BACKGROUND: In a two-part clinical study, we investigated the effect of the administration of fluids "prehydration" on the physical properties of cerebrospinal fluid (CSF) and intrathecal spread of local anesthetics. METHODS: First, in the clinical spinal anesthesia study, 68 patients were allocated randomly into the prehydration or nonprehydration groups. One group was prehydrated with 10 mL/kg of lactated Ringer's solution, and spinal anesthesia was performed with 12 mg of 0.5% isobaric tetracaine in all patients at the lumbar level. The arterial blood pressure, heart rate, and sensory block level were assessed. Second, in a magnetic resonance image study, 24 male volunteers were enrolled. CSF motion variables were measured after infusion of 10 mL/kg of lactated Ringer's solution to examine the net flow and volume displacement of the CSF at the L2-3 disk level. RESULTS: In the clinical study, there were no significant differences in arterial blood pressure, heart rate, and median peak sensory block level between the two groups, but the median time to reach peak sensory block level (26.4 +/- 15.7 vs 16.5 +/- 9.2 min, P < 0.05) was longer in group P. In posthydration magnetic resonance images, the CSF regurgitant fraction (caudal flow) was significantly increased after hydration, but the stroke volume, absolute stroke volume, mean flux, stroke distance, and mean velocity in the cranial direction were significantly decreased. CONCLUSIONS: Rapid crystalloid prehydration can affect CSF flow in the lumbar region, reducing cephalic spread of 0.5% isobaric tetracaine and delaying the time to reach the peak sensory level.

Blocking noise but not music lowers bispectral index scores during sedation in noisy operating rooms.

STUDY OBJECTIVE: To determine whether playing music or blocking noise can reduce bispectral index (BIS) values during propofol sedation. DESIGN: Prospective, randomized, single-blinded study. SETTING: Operating room. PATIENTS: 63 ASA physical status I and II patients, aged 55 to 75 years, undergoing total knee replacement. INTERVENTIONS: Patients were divided into three groups: noise, silence, and music. After induction of combined spinal-epidural anesthesia, sedation was begun with 1.2 mug/mL of propofol in a target-controlled infusion. In the silence group, patients' ears were packed tightly to block ambient noise, whereas patient-selected music was applied to patients in the music group. Patients in the noise group were exposed to ambient operating room noise. MEASUREMENTS: Bispectral index measurement was recorded 7 times during operation. Ambient room noise was recorded at the same time sequence. MAIN RESULTS: Sound level was highest when the saw (T3, 80.25 dB) and the impact device (T4, 80.98 dB) were in use. Bispectral index scores in the silence group during those times (T3, 68.5 vs 76.9, P = 0.025, and T4, 67.6 vs 78, P = 0.005) were lower than in the noise group. However, BIS scores were similar in the noise and music groups. Preoperative anxiety level, postoperative comfort level, and pain scores were similar in all groups. CONCLUSION: Blocking noise is more effective than playing music in reducing BIS scores during propofol sedation in a noisy environment.

The Mid-term Results of Thoracoscopic Closure of Atrial Septal Defects.

BACKGROUND AND OBJECTIVES: Recently, minimally invasive surgical (MIS) techniques including robot-assisted operations have been widely applied in cardiac surgery. The thoracoscopic technique is a favorable MIS option for patients with atrial septal defects (ASDs). Accordingly, we report the mid-term results of thoracoscopic ASD closure without robotic assistance. SUBJECTS AND METHODS: We included 66 patients who underwent thoracoscopic ASD closure between June 2006 and July 2014. Mean age was 27±9 years. The mean size of the ASD was 25.9±6.3 mm. Eleven patients (16.7%) had greater than mild tricuspid regurgitation (TR). The TR pressure gradient was 32.4±8.6 mmHg. RESULTS: Fifty-two (78.8%) patients underwent closure with a pericardial patch and 14 (21.2%) underwent direct suture closure. Concomitant procedures included tricuspid valve repair in 8 patients (12.1%), mitral valve repair in 4 patients (6.1%), and right isthmus block in 1 patient (1.5%). The mean length of the right thoracotomy incision was 4.5±0.9 cm. The mean cardiopulmonary bypass time was 159±43 minutes, and the mean aortic cross clamp time was 79±29 minutes. The mean hospital stay lasted 6.1±2.6 days. There were no early deaths. There were 2 reoperations. One was due to ASD patch detachment and the other was due to residual mitral regurgitation after concomitant mitral valve repair. However, there have been no reoperations since July 2010. There were 2 pneumothoraxes requiring chest tube re-insertion. There was one wound dehiscence in an endoscopic port. The mean follow-up duration was 33±31 months. There were no deaths, residual shunts, or reoperations during follow-up. CONCLUSION: Thoracoscopic ASD closure without robotic assistance is feasible, suggesting that this method is a reliable MIS option for patients with ASDs.