Tsung-Hsiao Shih

Use of Spectral Entropy Monitoring in Reducing the Quantity of Sevoflurane as Sole Inhalational Anesthetic and in Decreasing the Need for Antihypertensive Drugs in Total Knee Replacement Surgery

BACKGROUND The use of spectral entropy for monitoring the depth of anesthesia or level of hypnosis in surgery or painful procedures can reduce the consumption of drugs and shorten the recovery time of total intravenous anesthesia such as by propofol. The aim of this study was to investigate: (1) the consumption of sevoflurane as the sole anesthetic; and (2) hemodynamic stability in orthopedic surgery with tourniquet inflation under the guidance of spectral entropy, in contrast with the conventional method. METHODS Sixty-five patients, ASA I or II, scheduled to undergo total knee replacement were enrolled and randomized into an entropy-guided group or a conventionally-monitored group. In the conventional group, the depth of anesthesia was judged by the clinical experience of the anesthesia provider based on the hemodynamic response. In the entropy group, state entropy (SE) and response entropy (RE) were kept within the range of 35-45 and an adequate gradient of 5-10 intraoperatively. The overall consumption of sevoflurane (mL) was monitored by the GE Datex-Ohemda S/5 Anesthetic Delivery Unit System. The physiologic changes during five major events in sequence in total knee replacement surgery, i.e., intubation, tourniquet inflation, skin incision, deflation and extubation, were observed closely over the first 5 minutes after each individual event. Within the first 5 minutes of each event, antihypertensive drugs were prohibited. The rest of the time, changes were recorded at 5-minute intervals and the use of rescue medication was allowed in case of need. We compared the heart rate, mean arterial pressure, SE, RE, sevoflurane concentration and rescue drugs in both groups. RESULTS The sevoflurane consumption was significantly lower in the entropy group than in the conventional group (27.79 +/- 7.4 mL vs. 31.42 +/- 6.9 mL; p < 0.05). During the first 5 minutes of each major event, there were no significant differences in hemodynamics between the two groups. In the ensuing time, entropy-guided anesthesia was associated with significantly less frequent need of antihypertensive drugs (0.94 vs. 1.48 times; p = 0.043), especially in the 45-60 minutes after tourniquet inflation (p = 0.012). CONCLUSION Using spectral entropy monitoring for guiding the depth of sevoflurane anesthesia in total knee replacement surgery can reduce its consumption and the frequency of use of antihypertensive drugs.

Evaluation of Risk Factors for Postoperative Prolonged Intubation in Premature Infants After Cryotherapy for Retinopathy of Prematurity

OBJECTIVE Premature infants are more prone to cardiorespiratory complications after surgery than term infants. Risk factors for postoperative apnea include post-conception age, gestational age, postnatal age, birth weight, history of respiratory distress syndrome, bronchopulmonary dysplasia, anemia, necrotizing enterocolitis, use of opioids or nondepolarizing muscle relaxants, aminophylline use, history of apnea, body weight at operation, and pre-existing disease. The aim of this study was to identify the most important factors associated with postoperative extubation and respiratory outcomes among premature infants undergoing cryotherapy for retinopathy of prematurity (ROP). METHODS We retrospectively analyzed the clinical records of 62 premature infants, with mean +/- standard deviation gestational age of 26.4 +/- 2.3 weeks, birth weight of 914.8 +/- 208.5 g, postconception age of 37.0 +/- 2.8 weeks, and body weight at the time of operation of 1970.0 +/- 446.8 g, who underwent cryotherapy for ROP. RESULTS Only 17 infants were successfully extubated within 2 hours after operation. The most predictive factor for successful or unsuccessful extubation was body weight at the time of operation. CONCLUSION Body weight at the time of operation was the most important factor associated with postoperative ventilatory support among premature infants under-going cryotherapy for ROP.

Low-Dose Dantrolene Is Effective in Treating Hyperthermia and Hypercapnia, and Seems Not to Affect Recovery of the Allograft After Liver Transplantation: Case Report

Dantrolene is the drug of choice in treatment of malignant hyperthermia. However, dantrolene is hepatotoxic; thus prolonged use is not recommended in patients with active hepatic disease such as acute hepatitis or active cirrhosis because it may result in fatal hepatic failure. Use of dantrolene in a patient with end-stage liver disease undergoing liver transplantation (LTx) in whom suspected malignant hyperthermia developed has been reported rarely. Its effect on the liver allograft, which has sustained cold, warm, and reperfusion injuries, is currently unknown. We report a case in which low-dose dantrolene administered intravenously during LTx was effective in treating hyperthermia, hypercapnia, and hyperkalemia. Furthermore, its reported hepatotoxic effect seemed to not affect recovery of the allograft after LTx.

Retrospective Cohort Study to Compare Anesthesia in Living Donor Liver Transplantation Recipients Who Received Single and Dual Liver Grafts

OBJECTIVE Dual graft living donor liver transplantation (LDLT) is an alternative way to overcome small-for-size syndrome in LDLT. Surgical technique and outcome of using dual grafts have been reported, but there are no reports regarding anesthetic management. The aim of the current study is to compare the anesthetic management of single graft and dual graft liver transplantation. METHODS AND PATIENTS Anesthesia records of 24 single graft liver transplantation recipients (GI) and 6 dual graft recipients (GII) were reviewed, analyzed, and compared retrospectively. Patient characteristics and intraoperative data between groups were compared with Mann-Whitney t test and Fishers exact test where appropriate. P value less than .05 was regarded as significant. RESULTS Patient characteristics and most of the intraoperative data were similar between groups. Significant difference was noted in the total anesthesia time and the anhepatic time. Both times were significantly longer in GII compared to GI. CONCLUSION Dual graft living donor liver transplantation is surely a technically more challenging and demanding procedure. Therefore the total anesthesia time is longer, especially the anhepatic phase, because there are more graft vessels to be reconstructed before reperfusion. Overall the anesthetic management in terms of blood transfusion, fluid administration, sodium bicarbonate, calcium supplement, and the number of patients requiring fractional diluted noradrenaline support for maintenance of acceptable hemodynamic were not much different between the 2 groups.

Impact of Early Release of the IVC Clamp from Different IVC Clamping Maneuvers on Changes in Hemodynamic Parameters in Living Donor Liver Transplantation

BACKGROUND The aim of this study was to evaluate the impact of different methods of inferior vena cava (IVC) clamping and release of the cross clamp on hemodynamic parameters of recipients during living donor liver transplantation. MATERIAL AND METHODS Ninety-six adult living donor liver transplantation patients were divided into 3 groups according to cross-clamp of the IVC for all the hepatic vein and portal vein reconstruction (G1), cross-clamp of the IVC only for hepatic vein reconstruction (G2), and side-clamp of the IVC for hepatic vein reconstruction (G3). In G2 and G2, the reconstructed hepatic vein was clamped instead of the IVC for portal vein reconstruction. The hemodynamic parameters among groups were compared by 1-way ANOVA and the complications in each group were compared using the Kruskal-Wallis test. RESULTS Changes in percentage of MAP and CO in G3 were significantly less than that of G1 and G2 for hepatic vein reconstruction. Hemodynamic parameters of G2 and G3 normalized to pre-clamped values during portal vein reconstruction, while the hemodynamics of G1 remained unstable. CONCLUSIONS Hemodynamic changes were less pronounced in LT with side-clamp of the inferior cava vein versus total cross-clamp. Early release of the IVC clamp minimized the hemodynamic changes. There were no differences in terms of outcome (morbidity and mortality).

The Effectiveness of Prophylactic Attachment of Adhesive Defibrillation Pads in Adult Living Donor Liver Transplantation

BACKGROUND The aim of current study is to present the effectiveness of prophylactic attachment of adhesive defibrillation electrode pads in adult living donor liver transplantation. MATERIAL AND METHODS We divided 487 adult living donor liver transplantation patients into 2 Eras according to the history of without (Era 1) and with (Era 2) pre-attachment of adhesive defibrillation pads. The incidences of intraoperative cardiac events requiring cardioversion or defibrillation, its management, and outcome between Era 1 and 2 were compared. RESULTS Two cases out of 124 patients (1.6%) in Era 1 had cardiac arrest. The closed chest cardiac massage in 1 cardiac arrest in Era 1 required trans-diaphragmatic open-chest cardiac massage followed by internal cardiac defibrillation due to difficulty in performing external defibrillation. Both patients of Era 1 had in-hospital mortality. Four patients of Era 2 (n=363) received electrical treatment (1.01%); 2 had paroxysmal tachycardia requiring cardio-version and the other 2 had ventricular fibrillation requiring closed-chest cardiac massage and external defibrillation. All 4 patients in Era 2 regained sinus rhythm after electrical treatment, tolerated the subsequent operation well, and had 100% survival to date. CONCLUSIONS Our results show that prophylactic attachment of adhesive defibrillation pads allows the immediate performance of cardioversion, conventional closed-chest CPR, and defibrillation if indicated without any delay and without interference with the sterility of the operation field. Our preliminary result is clear and encouraging.

Anesthesia management and fluid therapy in right and left lobe living donor hepatectomy

OBJECTIVE Right lobe living donor hepatectomy poses a greater risk for the donor in relation to blood loss. The aims of this study were to compare anesthetic and intraoperative fluid management in right and left lateral segment living donor hepatectomy. PATIENTS AND METHODS The anesthesia records of living donor hepatectomy patients were retrospectively reviewed. Donor age and weight, anesthesia time, central venous pressure, blood loss, blood product transfusion, intravenous fluids used, doses of furosemide, and urine output were compared and analyzed between groups using the Mann Whitney U test. RESULTS Forty-six patients underwent living donor left lateral segment hepatectomy (Group I); while 31 patients underwent right lobe hepatectomy (Group II). The mean blood loss in Group II was significantly higher compared to Group I (118 ± 81 mL vs 68 ± 64 mL), but clinically such amount of blood loss was not high enough to affect the hemodynamics. The fluid management was therefore not meaningfully different between the two groups. No blood transfusions or colloid infusions were required for either group. Urine output, hemoglobin changes, blood urea nitrogen, and serum creatinine pre- and postoperatively were not significantly different between groups. CONCLUSIONS As long as blood loss is minimal, we found no difference in the anesthetic management and fluid replacements between right and left lateral segment living donor hepatectomy.

Eye Protection in Liver Transplantation Patients under General Anesthesia

BACKGROUND Opsite (Smith & Nephew, Hull, UK) is widely used in wound care but its use in eye protection against corneal abrasion during major surgery is rarely reported. The purpose of the current study is to compare the effectiveness of using Opsite in eye protection with either wet gauze alone or with wet gauze following application of eye ointment in patients undergoing living donor liver transplantation (LDLT). METHODS This is a prospective, double-blinded, randomized controlled trial. Forty-one patients undergoing liver transplantation were enrolled. One eye of each patient was protected with sterile gauze soaked with normal saline solution and covered with Opsite. Duratears (ALCON, Fort Worth, Tex, United States) ointment was applied to the other eye before covering it with sterile wet gauze and Opsite (ointment group). The corneal examination was carried out after fluorescein staining before and at the end of surgery by the same doctor. A Student t-test and a χ2 test were used for the statistical analyses. RESULTS Forty-one patients with 82 eyes were observed in this study. No corneal epithelial defects were found in either the normal saline group or the ointment group. CONCLUSION Opsite combined with wet gauze with or without additional eye ointment provided 100% protection against corneal abrasion in patients undergoing LDLT.

Clinical Beneficial Effects of Using Crystalloid only in Recipients of Living Donor Liver Transplantation

Objective: Liver transplantation (LT) is a major surgery associated with intraoperative massive fluid shift, which is usually replaced by crystalloid, 5% albumin (colloid) and blood products. We studied 15 patients from 477 consecutive recipients of adult living donor liver transplantation. Each patient received crystalloid only during LT. Whether LT provides any clinical benefit is not clear and must be determined. Methods and Patients: The anesthesia records of 477 adult LDLT were reviewed retrospectively. The patients were divided into three groups according to the fluids received. Group I (GI) had received blood products, 5% albumin and crystalloid, group II (GII) received 5% albumin and crystalloid, and group III (GIII) received crystalloid only. The characteristic intraoperative variable and postoperative acute rejection and survival rate were compared amongst groups by using One Way ANOVA post hoc with Bonferroni and by Ficher’s Exact test and Chi-square χ2 test. Results and Conclusions: GIII had less intraoperative ascites and blood loss; they also had more stable hemodynamics. Furthermore, they could be extubated significantly earlier than GI, and the one- and three-year survival rates were excellent, with 100% in GIII, while that of GI and GII were 94.1%, 90.5% and 98.6%, 94.5%, respectively.

Effect and Outcome of Intraoperative Fluid Restriction in Living Liver Donor Hepatectomy

Background The purpose of this study was to evaluate the effect and outcome of intraoperative fluid restriction in living liver donor hepatectomy, regarding changes in intraoperative CVP levels, blood loss, and postoperative renal function. Material/Methods The charts of 167 patients were reviewed and analyzed retrospectively. Intraoperative central venous pressure levels, blood loss, fluids infused, and urine output per hour, before and after the liver allograft procurement, were calculated. Perioperative renal functions were also analyzed. Results Fluid infused before and after liver allograft procurement was 3.21±1.5 and 9.0±3.9 mL/Kg/h and urine output was 1.5±0.7 and 1.8±1.4 mL/Kg/h, respectively. Intraoperative estimated blood loss was 91.3±78.9 mL. No patients required blood transfusion. Their preoperative and postoperative hemoglobin were 12.3±2.7 and 11.7±1.7 g/dL. CVP levels decreased gradually from 10.4±3.0 to a low of 8.1±1.9 mmHg at the time of transection of the liver parenchyma. Renal functions were not significantly affected based on the determination of BUN and creatinine levels. Conclusions The methods used to lower CVP are moderate and slow, with 2 main goals achieved: minimal blood loss (91.3±78.9 ml) and no blood transfusion. Furthermore, it did not have any negative effect on renal function.