Usability of Esophageal Doppler for Monitoring of Concealed Retroperitoneal Hemorrhage during Laparoscopy Assisted Subtotal Gastrectomy / 대한구급학회지

Hemodynamic monitoring is an essential element in the management of perioperative patients. In addition, anesthesiologists routinely used blood pressure (invasive or non invasive), heart rate, urinary output and central venous pressure as monitoring modalities. Esophageal doppler monitoring, as a minimally invasive hemodynamic assessment tool, has a good correlation with pulmonary artery catheterization in measuring cardiac output. We experienced a case of concealed retroperitoneal hemorrhage in a patient who underwent a laparoscopic subtotal gastrectomy. When surgeons tried to close trocar sites, the patient's blood pressure dropped rapidly. At laparoscopy, we could not find gross bleeding. However, we could detect hypovolemia by esophageal doppler monitoring (CardioQ, Deltex(TM), UK). The procedure was converted to open laparotomy. Thereafter, we could find retroperitoneal hemorrhage, and vascular repair was done successfully. The patient recovered without any other complications.

Validity of Corrected Flow Time (FTc) as a Predictor of Fluid Responsiveness in Patients with Sepsis-induced Hypotension

PURPOSE: To determine the validity of corrected flow time (FTc) as a predictor of fluid responsiveness for patients with sepsis-induced hypotension in the emergency department. METHODS: A total of 26 adult patients, who presented in the emergency department with sepsis-induced hypotension with spontaneous breathing, were enrolled in this prospective, interventional study. These patients were monitored by Esophageal Doppler (ED); FTc, central venous pressure (CVP), stroke volume index (SVI), and inferior vena cava diameter (IVCD) were measured before and after fluid challenge. Responsiveness to fluid challenge was defined as an SVI increase> or =10%. Receiver operating characteristic (ROC) curves were constructed and compared to evaluate the overall performance of preload indices (CVP, FTc, IVCD) in terms of predicting fluid responsiveness. RESULTS: Of the hemodynamic parameters initially measured, there were statistically significant differences in FTc and CVP between the responsive and unresponsive groups. Before and after fluid challenge, noticeable changes were observed in mean arterial pressure (MAP), CVP and IVCD between the two groups. Only the responsive group demonstrated statistical difference in FTc. The areas under the curves for FTc (0.870; 95% CIs, 0.708-0.979; p=.009) were significantly greater than those for CVP and IVCD. CONCLUSION: The corrected flow time (FTc) method may be a good predictor of fluid responsiveness relative to sepsis-induced hypotension for patients in the emergency department.

Validity of Corrected Flow Time (FTc) as a Predictor of Fluid Responsiveness in Patients with Sepsis-induced Hypotension

PURPOSE: To determine the validity of corrected flow time (FTc) as a predictor of fluid responsiveness for patients with sepsis-induced hypotension in the emergency department. METHODS: A total of 26 adult patients, who presented in the emergency department with sepsis-induced hypotension with spontaneous breathing, were enrolled in this prospective, interventional study. These patients were monitored by Esophageal Doppler (ED); FTc, central venous pressure (CVP), stroke volume index (SVI), and inferior vena cava diameter (IVCD) were measured before and after fluid challenge. Responsiveness to fluid challenge was defined as an SVI increase> or =10%. Receiver operating characteristic (ROC) curves were constructed and compared to evaluate the overall performance of preload indices (CVP, FTc, IVCD) in terms of predicting fluid responsiveness. RESULTS: Of the hemodynamic parameters initially measured, there were statistically significant differences in FTc and CVP between the responsive and unresponsive groups. Before and after fluid challenge, noticeable changes were observed in mean arterial pressure (MAP), CVP and IVCD between the two groups. Only the responsive group demonstrated statistical difference in FTc. The areas under the curves for FTc (0.870; 95% CIs, 0.708-0.979; p=.009) were significantly greater than those for CVP and IVCD. CONCLUSION: The corrected flow time (FTc) method may be a good predictor of fluid responsiveness relative to sepsis-induced hypotension for patients in the emergency department.

The hemodynamic effects of a reversed Trendelenburg in elderly patients with increased cardiac risk during laparoscopic cholecystectomy / 대한마취과학회지

BACKGROUND: We studied the hemodynamic changes induced by pneumoperitoneum and a reversed Trendelenburg in elderly patients with increased cardiac risk (ASA class III; n = 30; age 70.8 +/- 4.9 years, mean +/- SD) and compared the results with elderly patients at normal risk (ASA class II; n = 30; age 69.2 +/- 4.1 years) during laparoscopic cholecystectomy. METHODS: The transesophageal Doppler monitor was performed after induction of general anesthesia (pre-incision), after onset of pneumoperitoneum (insufflation), after head-up (20degrees) and a left lateral tilt (15degrees) (reversed Trendelenburg) and after deflation and horizontal position (desufflation). Mean arterial pressure (MAP), heart rate, cardiac index (CI) and systemic vascular resistance (SVR) were measured, respectively. RESULTS: Induction of pneumoperitoneum and head-up tilt in patients with cardiac risk resulted significantly in a decrease in CI and an increase in SVR compared with patients with normal risk (P < 0.05), and that remained until deflation, but no interval changes in MAP and heart rate. The CI, MAP and heart rate decreased and SVR increased significantly in patients with cardiac risk compared with patients with normal risk before incision (P < 0.05). No complications occurred. The results indicate that pneumoperitoneum and a reversed Trendelenburg are associated with significant but relatively benign hemodynamic changes. CONCLUSIONS: Anesthesia for laparoscopic cholecystectomy in elderly patients with increased cardiac risk should be performed with an adequate hemodynamic monitoring.

Comparison with hemodynamic changes of laparoscopic surgery by body position

BACKGROUND: The authors evaluated the hemodynamic effects of body position measured by esophageal Doppler monitor (EDM) during laparoscopic cholecystectomy or gynecologic laparoscopic surgery. METHODS: Fifty patients scheduled to undergo laparoscopic cholecystectomy (Group C) or gynecologic laparoscopic surgery (Group G), were divided into two groups. Pneumoperitoneum was instituted by CO2 gas and the intraperitoneal pressure was kept under 12 mmHg. Hemodynamic parameters at critical points were measured by the use of EDM: before skin incision (T1), 5, 10 and 15 min after changing position (T2, T3 and T4), and 5 min after CO2 exsufflation (T5). RESULTS: MAP (mean arterial pressure) was significantly higher in Group G when compared with Group C 10 min after changing position (T3) (P< 0.05). CO (cardiac output) was significantly decreased in Group G when compared with Group C 10 min after changing position (T3) (P< 0.05). And there were not significant differences in HR (heart rate) between two groups. PV (peak velocity) was significantly decreased in Group G when compared with Group C 10 min after changing position (T3) (P< 0.05). And there were not significant differences in FTc (corrected flow time) between two groups. But FTc in Group C was restored after CO2 exsufflation, FTc in Group G was not restored after CO2 exsufflation. CONCLUSIONS: Changing position in the gynecologic laparoscopic surgery group can elevate MAP and decrease CO. Therefore, careful caution is required in patients with cardiovascular disease who are undergoing gynecologic laparoscopic surgery.

Hemodynamic Effects of Nicardipine Measured by Esophageal Doppler Monitor during Gynecologic Laparoscopic Surgery

BACKGROUND: The authors performed this study to investigate the hemodynamic effect of nicardipine using an esophageal Doppler monitor (EDM) during gynecologic laparoscopic surgery. METHODS: Forty patients scheduled to undergo gynecologic laparoscopic surgery, were divided into two groups; the control group (Group C) and the nicardipine group (Group N). Pneumoperitoneum was initiated using CO2 gas and the intraperitoneal pressure was kept under 12 mmHg. Hemodynamic parameters at critical points were measured using EDM, i.e., before skin incision (T1), 5, 10 and 15 min after the initiation of pneumoperitoneum (T2, T3 and T4), and 5 min after deflation (T5). RESULTS: Mean arterial pressure (MAP) was significantly lower in Group N patients than in Group C patients at 5 and 10 min after the initiation of pneumoperitoneum (T2 and T3) (P < 0.05). No significant heart rate (HR) differences were observed between the two study groups. Cardiac output (CO), peak velocity (PV) and corrected flow time (FTC) were significantly higher in Group N at 10 min after the initiation of pneumoperitoneum (T3) (all P < 0.05). CONCLUSIONS: The nicardipine continuous infusion at 0.5?2.0microg/ kg/min is effective at attenuating hemodynamic changes after pneumoperitoneum during gynecologic laparoscopic surgery.

Hemodynamic Changes using Partial CO2 Rebreathing Method and Esophageal Doppler Monitor during Bilateral Total Knee Replacement Arthroplasty / 대한마취과학회지

BACKGROUND: We studied hemodynamic changes using a noninvasive partial CO2 rebreathing cardiac output method (NICO) and esophageal Doppler monitor (EDM), and metabolic changes in elderly patients undergoing bilateral total knee replacement arthroplasty (BTKA). METHODS: Twenty patients undergoing BTKA were studied. Hemodynamic and metabolic parameters were measured before tourniquet inflation (TI), 0, 3, 6, 9, 15, 30, 45 min after TI, and 0, 3, 6, 9, 15, 30 min after tourniquet deflation (TD) and skin suture. Stroke volume (SV), cardiac output (CO) and systemic vascular resistance (SVR) were measured using NICO and EDM. RESULTS: Mean blood pressure (MBP), central venous pressure (CVP), and SVR had significant increases in TI, and decreases in TD compared with value measured before TI (baseline value). Especially, MBP had higher decrease in the second tourniquet compared with first tourniquet, SV and CO were decreased in TI, and increased in TD compared with baseline value, HR had significant increases in the TD of second tourniquet. pH and lactate were shown significantly lower values at the second tourniquet compared with the first tourniquet (P < 0.05). The bias and precision derived from CO between EDM and NICO was 0.27 +/- 0.41 L/min, and CO by NICO was smaller than that by EDM. The correlation coefficient between NICO and EDM was calculated to be 0.43. CONCLUSIONS: MBP, SV, CO, pH and lactate were shown to be higher in the second tourniquet in BTKA. NICO showed lower CO compared with EDM after TD in patients undergoing BTKA, but statistically insignificant at most measurement.

Utility of Esophageal Doppler and the Hemodynamic Effect of Nicardipine during a Laparoscopic Cholecystectomy / 대한마취과학회지

BACKGROUND: We performed this study to investigate the hemodynamic effect of nicardipine using an esophageal Doppler monitor (EDM) during a laparoscopic cholecystectomy. METHODS: Forty patients scheduled to undergo a laparoscopic cholecystectomy, were divided into two groups; the control group (Group C) and the nicardipine group (Group N). Pneumoperitoneum was initiated by CO2 gas and the intraperitoneal pressure was kept under 12 mmHg. Hemodynamic parameters at critical points were measured by the use of EDM: before skin incision (T1), 5, 10 and 15 min after the initiation of pneumoperitoneum (T2, T3 and T4), and 5 min after deflation (T5). RESULTS: The mean arterial pressure (MAP) was significantly lower in the Group N patients when compared to the Group C patients 5, 10 and 15 min after the initiation of pneumoperitoneum (T2, T3 and T4), and 5 min after deflation (T5)(P < 0.05). There was no significant differences in heart rate (HR) between patients in the two groups. The cardiac output (CO) was significantly increased in the Group N patients when compared to the Group C patients 5 min after the initiation of pneumoperitoneum (T2)(P < 0.05). The peak velocity (PV) was significantly increased in the Group N patients when compared to the Group C patients 5 and 10 min after the initiation of pneumoperitoneum (T2 and T3)(P < 0.05). The corrected flow time (FTC) was significantly increased in the Group N patients when compared to the Group C patients 5 min after the initiation of pneumoperitoneum (T2)(P < 0.05). CONCLUSIONS: We conclude that nicardipine continuous infusion with 0.5-2.0microgram/kg/min is effective in attenuating the hemodynamic change after pneumoperitoneum during a laparoscopic cholecystectomy.

Fluid Management in Kidney Transplantation: Central Venous Pressure Guided vs Esophageal Doppler Monitoring / 대한마취과학회지

BACKGROUND: Maximizing renal blood flow during reperfusion of the transplanted kidney could be the key factor to prevent acute tubular necrosis (ATN). To achieve such a goal, augmentation of circulating blood volume is necessary. We evaluated stroke volume monitored or CVP guided volume expansion method and, which method would be better for the outcome. METHODS: Forty three patients (Group I) of 79 patients received maximum hydration guided by CVP maintaining 12-15 mmHg, other 36 patients (Group II) received fluid to achieve maximum SV using esophageal doppler monitor. All patients received albumin (maximal dose < 1 g/kg), mannitol (20%, 200 ml), and furosemide (40 mg) before renal artery reperfusion. Postoperative tests for evaluation of renal function, incidence of ATN and morbidity and hospital stay in patient were investigated. RESULTS: Amount of fluid infused were 3,891 +/- 1,145 ml in Group I and 2,981 +/- 936.4 ml in Group II. Incidence of ATN (Group I; 9.3% and Group II; 8.3%), tests for renal function were not statistically significant in both Group, but two patients in Group I was administered in intensive care unit (ICU). CONCLUSIONS: Lesser fluid was administered in the Group used with SV augmentation than conventional CVP guided group and there was no difference in the incidence of ATN between two group. In kidney transplantation, esophageal doppler monitoring may be better in fluid management than CVP monitoring.

The Effect of Pneumoperitoneum on Thoracoabdominal Aortic Blood Flow in Laparoscopic Cholecystectomy / 대한마취과학회지

BACKGROUND:We performed this study to determine the influence of the administration of pneumoperitoneum on the blood flow of the thoracoabdominal aorta during laparoscopic cholecystectomy (LC). METHODS: Ten patients for LC were enrolled in this study. Anesthesia was performed with propofol, fentanyl and rocuronium. Pneumoperitoneum was made by CO2 gas intraperitoneal instillation at an intraperitoneal pressure of 10-12 mmHg. Peak velocity of blood flow in the systolic phase (PV), mean acceleration of blood flow from the start of systole (MA) and systolic flow time corrected for heart rate (FTc), measured by esophageal doppler monitoring (EDM), and heart rate (HR) and mean brachial BP (MBP) were measured 1, 5 and 10 min after the institution of pneumoperitoneum, (T1, T5 and T10) and compared with those before the institution of pnuemoperotoneum (T0). LC was started after recording all measurements and a position change to the reverse-Trendelenberg position. RESULTS: PV, MA, FTc and HR showed no significant change throughout this study, but MBP at T5 and T10 (110.1 +/- 18.5 mmHg and 107.8 +/- 10.4 mmHg) were significantly higher than at T0 (84.9 +/- 12.9 mmHg) (P = 0.002 and 0.005 respectively). CONCLUSIONS: The administration of pneumoperitoneum neither changed nor interferenced with abdominal aortic blood flow.

Comparison of Hemodynamic Data obtained from a Pulmonary Artery Catheter vs. Esophageal Doppler during Liver Transplantation / 대한마취과학회지

BACKGROUND: The measurement of cardiac output is an essential part of anesthetic practice in patients undergoing liver transplantation. A thermodilution technique, using a pulmonary artery catheter is currently accepted as the gold standard in clinical practise. However, its use is associated with several limitations. METHODS: An esophageal doppler monitor was compared with the thermodilution technique in 22 patients undergoing split graft transplantation from a living donor. Six measurement were taken during liver transplantation, 1) control, 2) dissection phase, 3) anhepatic phase, 4) reperfusion phase, 5) after hepatic artery anastomosis, and 6) end of surgery. RESULTS: Significant difference were observed between the two measurement at all times studied with a strong correlation, except at the end of surgery (r > 0.4). CONCLUSIONS: The use of esophageal doppler monitor results in cardiac output measurements which are considerably different from those obtained using thermodilution, but a strong correlation exists between two methods. Thus the use of esohageal monitoring can be recommended in patients undergoing liver transplantation for trend monitoring.

Hemodynamic Changes Measured by Esophageal Doppler Monitor during Laparoscopic Cholecystectomy and Gynecologic Pelviscopy / 대한마취과학회지

BACKGROUND: Laparoscopic cholecystectomy and gynecologic pelviscopy need to induce pneumoperitoneum to allow visualization of the operative field, but the former requires a head-up position whereas the latter needs a Lithotomy-Trendelenburg position. The authors observed hemodynamic changes using an esophageal doppler monitor in both cases. METHODS: Eight females planned for laparoscopic cholecystectomy were assigned to Group 1 and 10 females for gynecologic pelviscopy were assigned to Group 2. Thiopental (5 mg/kg) and vecuronium (0.1 mg/kg) were used to induce general anesthesia. 50% O2-N2O and 1.5 vol.% isoflurane were used to maintain anesthesia. Mechanical ventilation was used with a tidal volume of 10 ml/kg and a respiratory rate of 12 breaths per minute. Mean arterial pressure, heart rate, end-tidal CO2 and peak airway pressure were measured and cardiac output, corrected flow time, and peak velocity were monitored using an esophageal doppler monitor in each group after inducing anesthesia, CO2 inflation, position change, and CO2 deflation. RESULTS: Mean arterial pressure increased in each group while changing position. No significant changes in the heart rate were observed in each group. End-tidal CO2 increased in each group after changing position, and remained elevated even with position reversal and deflation. Peak airway pressure was elevated in each group after CO2 inflation and increased more so with changing posture in group 2 (post inflation: 18.5 +/- 1.4 cmH2O, after position change: 21.4 +/- 2.0 cmH2O). Cardiac output and cardiac index were reduced after the induction of pneumoperitoneum in each group, and reduced more on changing posture in group 2 (CO: 5.9 +/- 2.0 L/min vs. 4.4 +/- 1.5 L/min, CI: 3.7 +/- 1.4 L/min/m2 vs. 2.7 +/- 1.1 L/min/m2). Stroke volume also reduced after changing posture in each group. Corrected flow time was not changed, but peak velocity decreased after CO2 inflation in each group (group 1: 97.4 +/- 30.0 cm/s vs. 78.9 +/- 27.3 cm/s, group 2: 111.9 +/- 14.1 cm/s vs. 88.3 +/- 12.6 cm/s). CONCLUSIONS: The Lithotomy-Trendelenburg position can augment the hemodynamic changes resulting from pneumoperitoneum. Therefore, additional caution is required in patients with cardiovascular disease who are undergoing gynecologic pelviscopy.

Hemodynamic Changes Using Esophageal Doppler during a Thoracoscopic Thoracic Sympathicotomy in Primary Hyperhidrosis / 대한마취과학회지

BACKGROUND: Among the treatments for hyperhidrosis, thoracoscopic sympathicotomy is comparatively easy and simple to operate, so complications rarely occur. Since the thoracic sympathetic nerve controls the cardiovascular system, there should be hemodynamic changes after the operation. However, little study has been done up on describing the overall hemodynamic changes occurring during operation. Therefore, we examined hemodynamic changes by Esophageal Doppler. METHODS: This research was conducted on thirteen patients with hyperhidrosis, from 15 to 50 years who were group 1 or 2, according to the American Society of Anesthesiologists (ASA) classification, and were without heart disease, respiratory disease or esophageal disease. Induction was done using TCI Diprivan 4.5microgram/ml, vecuronium 0.1 mg/kg at maintained with 50% nitrous oxide. Hemodynamic parameters such as heart rate, mean arterial pressure and cardiac output and tissue oximeter were examined after anesthesia was induced, and CO2 given, that is, immediately before thoracic sympathicotomy and after thoracic sympathicotomy. RESULTS: The mean heart rate was 89 +/- 12 beats/min just before thoracic sympathicotomy, after surgery this decreased statistically. Mean tissue oxygen saturation in the arm was 77 +/- 10% just after surgery, and this was a significant increase compared with that before surgery (P<0.05). Cardiac output by esophageal doppler decreased statistically after induction. CONCLUSIONS: During thoracoscopic thoracic sympathicotomy in primary hyperhidrosis, the heart rate decreased, cardiac output using esophageal doppler showed a significant decrease at each time, and there was not any differences between each time.

Cardiac Output Estimations by Esophageal Doppler Cannot Replace Estimations by the Thermodilution Method in Off-pump Coronary Artery Bypass Surgery Patients / 대한마취과학회지

BACKGROUND: Esophageal doppler is discribed as a non-invasive alternative to cardiac output (CO) estimation by thermodilution, the current bedside "gold standard". This study was designed to evaluate the accuracy of CO estimations performed by esophageal doppler (EDCO), compared to those obtained using a continuous CO pulmonary flotation catheter (TDCO). METHODS: In 16 patients undergoing off-pump coronary artery bypass surgery, CO was measured simultaneously by the esophageal doppler and the thermodilution method, after induction (A), after sternotomy (B), after coronary revascularization (C), and after sternal closure (D). Agreement between the TDCO and EDCO estimations was assessed by analyzing their mean differences and the distribution of these differences. Relative CO changes (percentages of the previous value) was analyzed by the same method. RESULTS: Both absolute CO values and relative CO changes by esophageal doppler showed a considerable scatter compared to those obtained using the thermodilution method. The bias (EDCO-TDCO) between the two mehtods was -0.8 +/- 2.7 L/min for A, -0.9 +/- 2.5 L/min for B, -0.9 +/- 3.6 L/min for C, and -0.6 +/- 2.7 (mean +/- 2 SD) L/min for D. On analyzing changes in CO, no significant method bias was found but 2 SD of the bias were +/- 74% for A to B, +/- 100% for B to C, and +/- 83% for C to D. CONCLUSIONS: These results suggest that CO estimations by esophageal doppler cannot replace estimations by the thermodilution method in patients undergoing off-pump coronary artery bypass graft surgery.

A Comparison of the Transoesophageal Doppler and Thermodilution Techniques for Cardiac Output Measurement in Off-Pump Coronary Artery Bypass Surgery Patients / 대한마취과학회지

BACKGROUND: The aim of this study was to compare the accuracy of measured cardiac output using the newly developed esophageal doppler device with that of the thermodilution method using a pulmonary artery catheter. METHODS: In 15 patients undergoing off-pump coronary artery bypass surgery, cardiac outputs were measured at four episodes of surgery; (1) after induction of anesthesia, (2) during dissection of the internal mammary artery, (3) during anastomosis of the left anterior descending artery, and (4) after closure of the pericardium. RESULTS: The bias between the two methods was 0.52 +/- 1.09 L/min. Analysis of the changes in cardiac output from sample episode 1 to 2, from sample episode 2 to 3 and from sample episode 3 to 4, expressed as percent change values, shows no significant differences between the two methods (P > 0.05). CONCLUSIONS: The esophageal doppler accurately reflects changes in cardiac output with time when compared with that of the thermodilution.

Is An Esophageal Doppler Monitor Useful in Hemodynamic Monitoring during a Laparoscopic Cholecystectomy? / 대한마취과학회지

BACKGROUND: To measure hemodynamic changes during a laparoscopic cholecystectomy (LC), we used a new, noninvasive esophageal doppler monitor (EDM). METHODS: Under general anesthesia, 17 patients undergoing a LC were prepared by inserting an EDM probe into the esophagus. Cardiac index (CI), corrected flow time (FTc), systemic vascular resistance (SVR), mean arterial pressure (MAP), and heart rate (HR) were measured 6 times-before pneumoperitoneum, 5 minutes after pneumoperitoneum, 5, 15, and 30 minutes after the reverse trendelenberg position and after exsufflation of CO2 gas. Complication and insertion time of the EDM were also recorded. Data was analyzed using a repeated measure ANOVA. RESULTS: CO2 gas insufflation resulted in an abrupt increase of SVR (51%), MAP (17%) and a decrease of CI (29%), FTc (13%). These changes were gradually restored, except the MAP. HR was not changed significantly. These findings correlated well with other studies using a thermodilution technique or transesophageal echocardiography. There was no complication with the EDM and insertion time was 182 32.3 sec. CONCLUSIONS: Since MAP and HR do not offer accurate hemodynamic information during pneumoperitoneum, other adequate cardiovascular monitors are required. An EDM can be used during LC because it provides CI and FTc by a simple and noninvasive method.