Hipertermia maligna: a propósito de un caso / Malignant hyperthermia: a case report

Malignant hyperthermia (MH) is a rare neuromuscular hereditary disorder, triggered in susceptible individuals by exposure to inhalational agents or succinylcholine and manifested as a hypermetabolic state. We report the case of a 22 years old male patient anesthetized with Desflurane in whom MH was suspected because of unexplained increased levels of End-Tidal carbon dioxide. Dantrolene was administered with good response. Respiratory acidosis and hyperkalemia were also detected but could be easily controlled. The postoperative period was uneventful with the exception of a superficial venous thrombosis at the dantrolene’s injection site. The patient was discharged eight days after the episode without sequela. Successful management of a malignant hyperthemia episode must include: early suspicion, asking for help and early treatment with dantrolene.

La Hipertermia Maligna es un trastorno neuromuscular hereditario infrecuente, manifestado por un estado hipermetabólico desencadenado en individuos susceptibles por la exposición a anestésicos halogenados o Succinilcolina. Se reporta el caso de un hombre de 22 años anestesiado con Desflurano, en quien el diagnóstico de Hipertermia Maligna se sospechó por la presencia de elevación inexplicada del CO2 espirado, que respondió a la suspensión del Desflurano y administración de Dantroleno. Se observó además hiperkalemia y acidosis respiratoria, que fueron fácilmente compensadas. La evolución postoperatoria fue satisfactoria, a excepción de una trombosis venosa superficial en el sitio de inyección del Dantroleno. El paciente fue dado de alta al 8avo día postoperatorio, sin secuelas. Las claves del manejo exitoso de un episodio de hipertermia maligna están en: Sospecha precoz, solicitar ayuda e inició rápido del tratamiento con Dantroleno.

Early postoperative recovery after intracranial surgical procedures. Comparison of the effects of sevoflurane and desflurane

ABSTRACT PURPOSE: To compared the effects of sevoflurane and desflurane on early anesthesia recovery in patients undergoing to craniotomy for intracranial lesions. METHODS: After IRB approval, the study included 50 patients aged 18-70 years who had ASA physical statuses of I-II and were scheduled for intracranial surgery. Patients were randomly divided into two groups: sevoflurane and desflurane. Anaesthesia was routinely induced in all patients followed by desflurane 5%-6% or sevoflurane 1%-2%. Moreover remifentanil infusion (0.05-0.2 mcg/kg/min) was adjusted to maintain mean arterial pressure (MAP) within 20% baseline and heart rate <90 bpm. Postoperatively, patients were evaluated over time for responses to painful stimulus, eye opening, hand squeezing, extubation, orientation and time required to achieve a Modified Aldrete Score of 9-10. Parametric and non-parametric data were assessed using Student's t- and Mann-Whitney U tests, respectively. A p<0.05 was taken as statistically significant. RESULTS: The times to responses to painful stimuli (7.7±2.7 vs. 4.8±1.7 min.; p<0.001), emergence (9.5±2.81 vs. 6.3±2.2 min.; p<0.001), hand-squeezing (12.1±2.9 vs. 8.2±2.3 min.; p<0.001), extubation (10.1±2.87 vs. 7.1±1.6 min.; p<0.001), orientation (15.3±3.2 vs. 10.3±2.7 min.; p<0.001) and Aldrete score of 9-10 (23.3±6.1 vs. 15.8±3.8 min.; p<0.001) were significantly lower with desflurane-based anaesthesia vs. sevoflurane-based anaesthesia. CONCLUSION: Desflurane yields early recovery functions and facilitates early postoperative neurologic examinations of intracranial surgery patients.

Can thiamine pyrophosphate prevent desflurane induced hepatotoxicity in rats?

ABSTRACT PURPOSE : To investigate the effects of thiamine pyrophosphate (TPP) against desflurane induced hepatotoxicity. METHODS : Thirty experimental animals were divided into groups as healthy (HG), desflurane control (DCG) , TPP and desflurane group (TDG). 20 mg/kg TPP was injected to intraperitoneally TDG. After one hour of TPP administration, desflurane was applied for two hours. After 24 hours, liver tissues of the animals killed with decapitation were removed. The oxidant/antioxidant levels and ALT, AST and LDH activities were measured. The histopathological examinations were performed in the liver tissues for all rats. RESULTS : Notwithstanding the levels of oxidants and liver enzymes were significantly increased (p<0.0001), antioxidant levels were significantly decreased in DCG (p<0.0001). On contrary to the antioxidant parameters were increased (p<0.05) the oxidant parameters and liver enzymes were decreased in TDG (p<0.0001). Whereas multiple prominent, congestion, hemorrhage and dilatation were observed in sinusoids and lymphocyte-rich inflammation results in the centrilobular and portal areas of liver tissue in DCG, these findings were observed less frequently in TDG. CONCLUSİON : Thiamine pyrophosphate prevented liver oxidative damage induced with desflurane and may be useful in prophylaxis of desflurane induced hepatotoxicity.

Pulse pressure variation and stroke volume variation under different inhaled concentrations of isoflurane, sevoflurane and desflurane in pigs undergoing hemorrhage

OBJECTIVES: Inhalant anesthesia induces dose-dependent cardiovascular depression, but whether fluid responsiveness is differentially influenced by the inhalant agent and plasma volemia remains unknown. The aim of this study was to compare the effects of isoflurane, sevoflurane and desflurane on pulse pressure variation and stroke volume variation in pigs undergoing hemorrhage. METHODS: Twenty-five pigs were randomly anesthetized with isoflurane, sevoflurane or desflurane. Hemodynamic and echocardiographic data were registered sequentially at minimum alveolar concentrations of 1.00 (M1), 1.25 (M2), and 1.00 (M3). Then, following withdrawal of 30% of the estimated blood volume, these data were registered at a minimum alveolar concentrations of 1.00 (M4) and 1.25 (M5). RESULTS: The minimum alveolar concentration increase from 1.00 to 1.25 (M2) decreased the cardiac index and increased the central venous pressure, but only modest changes in mean arterial pressure, pulse pressure variation and stroke volume variation were observed in all groups from M1 to M2. A significant decrease in mean arterial pressure was only observed with desflurane. Following blood loss (M4), pulse pressure variation, stroke volume variation and central venous pressure increased (p <0.001) and mean arterial pressure decreased in all groups. Under hypovolemia, the cardiac index decreased with the increase of anesthesia depth in a similar manner in all groups. CONCLUSION: The effects of desflurane, sevoflurane and isoflurane on pulse pressure variation and stroke volume variation were not different during normovolemia or hypovolemia.

Effect of Propofol and Desflurane on Immune Cell Populations in Breast Cancer Patients: A Randomized Trial

Several factors can affect the perioperative immune function. We evaluated the effect of propofol and desflurane anesthesia on the surgery-induced immune perturbation in patients undergoing breast cancer surgery. The patients were randomly assigned to receive propofol (n = 20) or desflurane (n = 20) anesthesia. The total and differential white blood cell counts were determined with lymphocyte subpopulations before and 1 hr after anesthesia induction and at 24 hr postoperatively. Plasma concentrations of interleukin (IL)-2 and IL-4 were also measured. Both propofol and desflurane anesthesia preserved the IL-2/IL-4 and CD4+/CD8+ T cell ratio. Leukocytes were lower in the propofol group than in the desflurane group at 1 hr after induction (median [quartiles], 4.98 [3.87-6.31] vs. 5.84 [5.18-7.94] 10(3)/microL) and 24 hr postoperatively (6.92 [5.54-6.86] vs. 7.62 [6.22-9.21] 10(3)/microL). NK cells significantly decreased 1 hr after induction in the propofol group (0.41 [0.34-0.53] to 0.25 [0.21-0.33] 10(3)/microL), but not in the desflurane group (0.33 [0.29-0.48] to 0.38 [0.30-0.56] 10(3)/microL). Our findings indicate that both propofol and desflurane anesthesia for breast cancer surgery induce a favorable immune response in terms of preservation of IL-2/IL-4 and CD4+/CD8+ T cell ratio in the perioperative period. With respect to leukocytes and NK cells, desflurane anesthesia is associated with less adverse immune responses than propofol anesthesia during surgery for breast cancer. (Clinical trial registration at https://cris.nih.go.kr/cris number: KCT0000939)

Plasma levels of interleukin-10 and nitric oxide in response to two different desflurane anesthesia flow rates / Níveis plasmáticos de interleucina-10 e óxido nítrico em resposta a duas taxas de fluxo em anestesia com desflurano / Niveles plasmáticos de interleucina-10 y óxido nítrico en respuesta a 2 tasas de flujo en anestesia con desflurano

OBJECTIVE: This study investigated interleukin-10 and nitric oxide plasma levels following surgery to determine whether there is a correlation between these two variables and if different desflurane anesthesia flow rates influence nitric oxide and interleukin-10 concentrations in circulation. MATERIALS AND METHODS: Forty patients between 18 and 70 years and ASA I-II physical status who were scheduled to undergo thyroidectomy were enrolled in the study. INTERVENTIONS: Patients were allocated into two groups to receive two different desflurane anesthesia flow rates: high flow (Group HF) and low flow (Group LF). MEASUREMENTS: Blood samples were drawn at the beginning (t 0) and end (t 1) of the operation and after 24 h (t 2). Plasma interleukin-10 and nitric oxide levels were measured using an enzyme-linked-immunosorbent assay and a Griess reagents kit, respectively. Hemodynamic and respiratory parameters were assessed. RESULTS: There was no statistically significant difference between the two groups with regard to interleukin-10 levels at the times of measurement. Interleukin-10 levels were increased equally in both groups at times t 1 and t 2 compared with preoperative concentrations. For both groups, nitric oxide circulating concentrations were significantly reduced at times t 1 and t 2 compared with preoperative concentrations. However, the nitric oxide value was lower for Group HF compared to Group LF at t 2. No correlation was found between the IL-10 and nitric oxide levels. CONCLUSION: Clinical usage of two different flow anesthesia forms with desflurane may increase interleukin-10 levels both in Group HF and Group LF; nitric oxide levels circulating concentrations were significantly reduced at times t 1 and t 2 compared with preoperative concentrations; however, at 24 h postoperatively they were higher in Group LF compared to Group HF. No correlation was detected between interleukin-10 and nitric oxide levels. .

OBJETIVO: este estudo investigou os níveis plasmáticos de interleucina-10 e óxido nítrico após cirurgia para determinar se há correlação entre essas duas variáveis e se diferentes taxas de fluxo de anestesia com desflurano influenciam as concentrações de interleucina-10 e óxido nítrico na circulação. MATERIAIS E MÉTODOS: quarenta pacientes, entre 18 e 70 anos de idade, estado físico ASA I-II, programados para tireoidectomia foram incluídos no estudo. INTERVENÇÕES: os pacientes foram divididos em dois grupos para receber dois fluxos diferentes de anestesia com desflurano: fluxo alto (Grupo FA) e fluxo baixo (Grupo FB). MENSURAÇÕES: amostras de sangue foram colhidas no início (t 0 ) e final (t 1 ) da cirurgia e após 24 h (t 2 ). Os níveis plasmáticos de interleucina-10 e óxido nítrico foram medidos usando um ensaio imunossorvente ligado à enzima um estojo de reagentes de Griess, respectivamente. Os parâmetros hemodinâmicos e respiratórios foram avaliados. RESULTADOS: não houve diferença estatisticamente significante entre os dois grupos em relação aos níveis de interleucina-10 níveis nos tempos de medição. Os níveis de interleucina-10 aumentaram igualmente em ambos os grupos nos tempos t 1 e t 2 em comparação com as concentrações no pré-operatório. Em ambos os grupos, as concentrações circulantes de óxido nítrico estavam significativamente reduzidas nos tempos t 1 e t 2 em comparação com as concentrações no pré-operatório. No entanto, o valor de óxido nítrico foi menor no Grupo FA que no Grupo FB no t 2 . Não houve correlação entre os níveis de IL-10 e óxido nítrico. CONCLUSÃO: o ...

OBJETIVO: este estudio investigó los niveles plasmáticos de interleucina-10 y óxido nítrico después de la cirugía para determinar si hay alguna correlación entre esas 2 variables y si diferentes tasas de flujo de anestesia con desflurano influyen en las concentraciones de interleucina-10 y óxido nítrico en la circulación. MATERIALES Y MÉTODOS: cuarenta pacientes, entre 18 y 70 años de edad, estado físico ASA I-II, programados para tiroidectomía se incluyeron en el estudio. INTERVENCIONES: los pacientes se dividieron en 2 grupos para recibir 2 flujos diferentes de anestesia con desflurano: flujo alto (grupo FA) y flujo bajo (grupo FB). MEDICIONES: se extrajeron muestras de sangre al inicio (t 0 ) y al final (t 1 ) de la cirugía y después de 24 h (t 2 ). Los niveles plasmáticos de interleucina-10 y óxido nítrico fueron medidos usando un ensayo de inmunoabsorción conectando un kit de reactivos de Griess, respectivamente. Se evaluaron los parámetros hemodinámicos y respiratorios. RESULTADOS: no hubo diferencia estadísticamente significativa entre los 2 grupos con relación a los niveles de interleucina-10 en los tiempos de medición. Los niveles de interleucina-10 aumentaron igualmente en ambos grupos en los tiempos t 1 y t 2 en comparación con las concentraciones en el preoperatorio. En ambos grupos, las concentraciones circulantes de óxido nítrico estaban significativamente reducidas en los tiempos t 1 y t 2 en comparación con las concentraciones en el preoperatorio. Sin embargo, el valor de óxido nítrico fue menor en el grupo FA que en el grupo FB en el t 2 . No hubo correlación entre los niveles de interleucina-10 y óxido nítrico. CONCLUSIÓN: el uso clínico de 2 flujos diferentes en anestesia con desflurano puede aumentar los ...

Randomized, controlled trial comparing the effects of anesthesia with propofol, isoflurane, desflurane and sevoflurane on pain after laparoscopic cholecystectomy / Estudo randômico controlado que compara os efeitos da anestesia com propofol, isoflurano, desflurano e sevoflurano sobre a dor pós-colecistectomia videolaparoscópica / Estudio aleatorizado controlado comparando los efectos de la anestesia con propofol, isoflurano, desflurano y sevoflurano sobre el dolor poscolecistectomía videolaparoscópica

Background: Pain is the primary complaint and the main reason for prolonged recovery after laparoscopic cholecystectomy. The authors hypothesized that patients undergoing laparoscopic cholecystectomy will have less pain four hours after surgery when receiving maintenance of anesthesia with propofol when compared to isoflurane, desflurane, or sevoflurane. Methods: In this prospective, randomized trial, 80 patients scheduled for laparoscopic cholecystectomy were assigned to propofol, isoflurane, desflurane, or sevoflurane for the maintenance of anesthesia. Our primary outcome was pain measured on the numeric analog scale four hours after surgery. We also recorded intraoperative use of opioids as well as analgesic consumption during the first 24 h after surgery. Results: There was no statistically significant difference in pain scores four hours after surgery (p = 0.72). There were also no statistically significant differences in pain scores between treatment groups during the 24 h after surgery (p = 0.45). Intraoperative use of fentanyl and morphine did not vary significantly among the groups (p = 0.21 and 0.24, respectively). There were no differences in total morphine and hydrocodone/APAP use during the first 24 h (p = 0.61 and 0.53, respectively). Conclusion: Patients receiving maintenance of general anesthesia with propofol do not have less pain after laparoscopic cholecystectomy when compared to isoflurane, desflurane, or sevoflurane. .

Justificativa e objetivo: a dor é a principal queixa e também o motivo principal de recuperação prolongada pós-colecistectomia laparoscópica. A nossa hipótese foi que os pacientes submetidos à colecistectomia laparoscópica apresentariam menos dor quatro horas após a cirurgia se recebessem manutenção anestésica com propofol em comparação com isoflurano, desflurano ou sevoflurano. Métodos: neste estudo prospectivo e randômico, 80 pacientes agendados para colecistectomia laparoscópica foram designados para receber propofol, isoflurano, desflurano ou sevoflurano para manutenção da anestesia. Nosso desfecho primário foi dor mensurada em escala analógica numérica quatro horas após a cirurgia. Também registramos o uso intraoperatório de opiáceos, bem como o consumo de analgésicos durante as primeiras 24 horas pós-cirúrgicas. Resultados: não houve diferença estatisticamente significante nos escores de dor quatro horas após a cirurgia (p = 0,72). Também não houve diferença estatisticamente significativa nos escores de dor entre os grupos de tratamento durante as 24 horas pós-cirúrgicas (p = 0,45). O uso intraoperatório de fentanil e morfina não variou significativamente entre os grupos (p = 0,21 e 0,24, respectivamente). Não houve diferença no consumo total de morfina e hidrocodona/APAP durante as primeiras 24 horas (p = 0,61 e 0,53, respectivamente). Conclusão: os pacientes que receberam propofol para manutenção da anestesia geral não apresentaram menos dor pós-colecistectomia videolaparoscópica em comparação com os que receberam isoflurano, desflurano ou sevoflurano. .

Justificación y objetivo: el dolor es el principal motivo de queja y también la principal razón de una prolongada recuperación tras una colecistectomía laparoscópica. Nuestra hipótesis fue que los pacientes sometidos a colecistectomía laparoscópica tenían menos dolor 4 h después de la cirugía cuando recibían propofol para la anestesia en comparación con isoflurano, desflurano o sevoflurano. Métodos: en este estudio prospectivo y aleatorizado, 80 pacientes programados para colecistectomía laparoscópica fueron designados para recibir propofol, isoflurano, desflurano o sevoflurano para el mantenimiento de la anestesia. Nuestro primer resultado fue el dolor medido en escala analógica numérica 4 h después de la cirugía. También registramos el uso intraoperatorio de opiáceos y el consumo de analgésicos durante las primeras 24 h del postoperatorio. Resultados: no hubo diferencias estadísticamente significativas en las puntuaciones del dolor 4 h después de la cirugía (p = 0,72). Tampoco hubo diferencias estadísticamente significativas en las puntuaciones del dolor entre los grupos de tratamiento durante las 24 h del postoperatorio (p = 0,45). El uso intraoperatorio de fentanilo y morfina no varió significativamente entre los grupos (p = 0,21 y 0,24 respectivamente). No hubo una diferencia en el consumo total de morfina e hidrocodona/APAP durante las primeras 24 h (p = 0,61 y 0,53 respectivamente). Conclusiones: los pacientes que recibieron propofol para el mantenimiento de la anestesia general no tenían menos dolor poscolecistectomía videolaparoscópica en comparación con los que recibieron isoflurano, desflurano o sevoflurano. .

Duration effect of desflurane anesthesia and its awakening time and arterial concentration in gynecologic patients

OBJECTIVES: To determine the awakening arterial blood concentration of desflurane and its relationship with the end-tidal concentration during emergence from various durations of general anesthesia. METHOD: In total, 42 American Society of Anesthesiologists physical status class I-II female patients undergoing elective gynecologic surgery were enrolled. General anesthesia was maintained with fixed 6% inspiratory desflurane in 6 l min-1 oxygen until shutoff of the vaporizer at the end of surgery. One milliliter of arterial blood was obtained for desflurane concentration determination by gas chromatography at 20 and 10 minutes before and 0, 5, 10, 15, and 20 minutes after the discontinuation of desflurane and at the time of eye opening upon verbal command, defined as awakening. Concentrations of inspiratory and end-tidal desflurane were simultaneously detected by an infrared analyzer. RESULTS: The mean arterial blood concentration of desflurane was 1.20% at awakening, which correlated with the awakening end-tidal concentration of 0.96%. The mean time from the discontinuation of desflurane to eye opening was 5.2 minutes (SD = 1.6, range 3-10), which was not associated with the duration of anesthesia (60-256 minutes), total fentanyl dose, or body mass index (BMI). CONCLUSIONS: The mean awakening arterial blood concentration of desflurane was 1.20%. The time to awakening was independent of anesthetic duration within four hours. Using well-assisted ventilation, the end-tidal concentration of desflurane was proven to represent the arterial blood concentration during elimination and could be a clinically feasible predictor of emergence from general anesthesia. .

Myocardial protection during off pump coronary artery bypass surgery: A comparison of inhalational anesthesia with sevoflurane or desflurane and total intravenous anesthesia.

Aims and Objectives: The objective of the study was to evaluate the myocardial protective effect of volatile agents-sevoflurane and desflurane versus total intravenous anesthesia (TIVA) with propofol in offpump coronary artery bypass surgery (OPCAB) by measuring cardiac troponin-T (cTnT) as a marker of myocardial cell death. Materials and Methods: The study was conducted on 139 patients scheduled to undergo elective OPCAB surgery. The patients were randomly allocated to receive anesthesia with sevoflurane, desflurane or TIVA with propofol. The cTnT levels were measured preoperatively, at arrival in postoperative intensive care unit, at 8, 24, 48 and 96 hours thereafter. Results: The changes in cTnT levels at all time intervals were comparable in the three groups. Conclusion: The study did not reveal any difference in myocardial protection after OPCAB with either sevoflurane or desflurane or TIVA using propofol as assessed by measuring serial cTnT values.

Entropy-guided end-tidal desflurane concentration during living donor liver transplantation

The three phases of living donor liver transplantation [LDLT] represent different liver conditions. The aim is to study the required end-tidal desflurane concentration [ET-Des] guided with entropy monitoring for the depth of anesthesia. After the Ethics and Research Committee approval, 40 patients were included in this prospective study. Anesthesia was maintained with Desflurane-O2-air. State entropy [SE] and Response entropy [RE] were kept between 40 and 60. Age and Model for End-stage Liver Disease [MELD] score were 45 +/- 10 years and 15.43 +/- 3.92, respectively. ET-Des were significantly lower in the anhepatic phase [2.8 +/- 0.4%] than in the pre-anhepatic and neohepatic phases [3.3 +/- 0.3%, 3.47 +/- 0.3%, respectively, P<0.001]. The SE and RE for pre-anhepatic, anhepatic, and neohepatic phases were [45.6 +/- 3.7, 47.4 +/- 3.2], [44.7 +/- 2.1, 46.4 +/- 2.04], and [46.1 +/- 3.3, 47.9 +/- 3.3], respectively, with no significant changes between the phases, P > 0.05. Total operative time was 651 +/- 88 minutes, and for each phase it was 276 +/- 11, 195 +/- 55, and 191 +/- 24 minutes, respectively. Significant changes were found in hemoglobin g/dl and hematocrit% between the three phases [10.28 +/- 1.5, 30.48 +/- 4.3], [9.45 +/- 1.34, 28.36 +/- 4.1], and [8.88 +/- 1.1, 26.63 +/- 3.5], P<0.05. The heart rate and mean blood pressures were stable despite the cardiac index demonstrated a significant reduction during the anhepatic phase [2.99 +/- 0.22] when compared to the pre-anhepatic and neohepatic phases [3.60 +/- 0.29] and [4.72 +/- 0.32], respectively, [P<0.05]. There was a significant correlation between CI and ET-Des% [r=0.604, P<0.05]. Inhalational anesthetic requirements differed from one phase to another during LDLT, with requirements being the least during the anhepatic phase. Monitoring of the anesthesia depth was required, to avoid excess administration, which could compromise the hemodynamics before the critical time of reperfusion

Hyperventilation accelerates the rise of arterial blood concentrations of desflurane in gynecologic patients

OBJECTIVES: Under a constant inspired concentration, the uptake of a volatile anesthetic into the arterial blood should mainly be governed by alveolar ventilation, according to the assumption that the patient's cardiac output remains stable during anesthesia. We investigated whether ventilation volume affects the rate of desflurane uptake by examining arterial blood concentrations. METHOD: Thirty female patients were randomly allocated into the following three groups: hyperventilation, normal ventilation and hypoventilation. Hemodynamic variables were measured using a Finometer, inspiratory and end-tidal concentrations of desflurane were measured by infrared analysis, and the desflurane concentration in the arterial blood (Ades) was analyzed by gas chromatography. RESULTS: During the first 10 minutes after the administration of desflurane, the Ades was highest in the hyperventilation group, and this value was significantly different from those obtained for the normal and hypoventilation groups. In addition, hyperventilation significantly increased the slope of Ades-over-time during the first 5 minutes compared with patients experiencing normal ventilation and hypoventilation, but there were no differences in these slopes during the periods from 5-10, 10-20 and 20-40 minutes after the administration of desflurane. This finding indicates that there were no differences in desflurane uptake between the three groups after the first 5 minutes within desflurane administration. CONCLUSIONS: Hyperventilation accelerated the rate of the rise in Ades following desflurane administration, which was time-dependent with respect to different alveolar ventilations levels.

Ionic Mechanisms of Desflurane on Prolongation of Action Potential Duration in Rat Ventricular Myocytes

PURPOSE: Despite the fact that desflurane prolongs the QTC interval in humans, little is known about the mechanisms that underlie these actions. We investigated the effects of desflurane on action potential (AP) duration and underlying electrophysiological mechanisms in rat ventricular myocytes. MATERIALS AND METHODS: Rat ventricular myocytes were enzymatically isolated and studied at room temperature. AP was measured using a current clamp technique. The effects of 6% (0.78 mM) and 12% (1.23 mM) desflurane on transient outward K+ current (I(to)), sustained outward current (I(sus)), inward rectifier K+ current (I(KI)), and L-type Ca2+ current were determined using a whole cell voltage clamp. RESULTS: Desflurane prolonged AP duration, while the amplitude and resting membrane potential remained unchanged. Desflurane at 0.78 mM and 1.23 mM significantly reduced the peak I(to) by 20+/-8% and 32+/-7%, respectively, at +60 mV. Desflurane (1.23 mM) shifted the steady-state inactivation curve in a hyperpolarizing direction and accelerated inactivation of the current. While desflurane (1.23 mM) had no effects on I(sus) and I(KI), it reduced the L-type Ca2+ current by 40+/-6% (p<0.05). CONCLUSION: Clinically relevant concentrations of desflurane appear to prolong AP duration by suppressing Ito in rat ventricular myocytes.

Echocardiographic evaluation and comparison of the effects of isoflurane, sevoflurane and desflurane on left ventricular relaxation indices in patients with diastolic dysfunction.

This prospective randomized study aims to evaluate and compare the effects of isoflurane, sevoflurane and desflurane (study drugs) on left ventricular (LV) diastolic function in patients with impaired LV relaxation due to ischemic heart disease using transesophageal Doppler echocardiography. After approval of the local ethics committee and informed consent, 45 patients scheduled for coronary artery bypass grafting surgery were enrolled in the study. Patients were selected by a preoperative Transthoracic Echocardiographic diagnosis of impaired relaxation or Grade 1 Diastolic Dysfunction. They randomly received fentanyl and midazolam anesthesia with 1 MAC of isoflurane (n=16), sevoflurane (n=14) or desflurane (n=15). Hemodynamic parameters and TEE derived ventricular diastolic relaxation indices before and after the study drug administration were compared. LV filling pressures were kept constant throughout the study period to exclude the effect of the loading conditions on diastolic function. Four patients in the sevoflurane group and three in the desflurane group were excluded from the study, after baseline TEE examination revealed normal diastolic filling pattern. All the three study drugs significantly reduced the systemic vascular resistance index with a significant increase in cardiac index. Mean arterial pressure was reduced by all the drugs, although the decrease was not statistically significant. Hemodynamic changes were comparable between all the three groups. In terms of LV relaxation indices, all three agents led to a significant improvement in diastolic function. Transmitral and Tissue Doppler E/A and Em/Am ratios improved significantly Transmitral and Tissue Doppler E/A and Em/Am ratios improved significantly accompanied by a significant decrease in deceleration time and isovolumetric relaxation time. The effect of all three agents on diastolic relaxation parameters was comparable. In conclusion , Isoflurane, sevoflurane and desflurane, do not appear to have a detrimental effect in patients with early diastolic dysfunction. On the contrary, these inhalational agents actually improve the LV relaxation. A significant reduction in afterload produced by these vapors can be a possible reason for these findings. The positive effect of these inhalational agents on LV relaxation can have a profound effect on the perioperative anesthetic management of patients with diastolic dysfunction.

Sevoflurane causes less arrhythmias than desflurane after off-pump coronary artery bypass grafting: A pilot study.

Background: Volatile anesthetics provide myocardial protection during cardiac surgery. Sevoflurane and desflurane are both efficient agents that allow immediate extubation after off-pump coronary artery bypass grafting (OPCABG). This study compared the incidence of arrhythmias after OPCABG with the two agents. Materials and Methods: Forty patients undergoing OPCABG with immediate extubation and perioperative high thoracic analgesia were included in this controlled, double-blind study; anesthesia was either provided using 1 MAC of sevoflurane (SEVO-group) or desflurane (DES-group). Monitoring of perioperative arrhythmias was provided by continuous monitoring of the EKG up to 72 hours after surgery, and routine EKG monitoring once every day, until time of discharge. Patient data, perioperative arrhythmias, and myocardial protection (troponin I, CK, CK-MB-ratio, and transesophageal echocardiography examinations) were compared using t-test, Fisher's exact test or two-way analysis of variance for repeated measurements; P < 0.05. Results: Patient data and surgery-related data were similar between the two groups; all the patients were successfully extubated immediately after surgery, with similar emergence times. Supraventricular tachycardia occurred only in the DES-group (5 of 20 patients), atrial fibrillation was significantly more frequent in the DES group versus SEVO-group, at five out of 20 versus one out of 20 patients, respectively. Myocardial protection was equally achieved in both groups. Discussion: Ultra-fast track anesthesia using sevoflurane seems more advantageous than desflurane for anesthesia, for OPCABG, as it is associated with significantly less atrial fibrillation or supraventricular arrhythmias after surgery.

A comparison of the effects of desflurane, sevoflurane and propofol on QT, QTc, and P dispersion on ECG.

The aim of this prospective, randomized, and double-blinded study was to compare the effects of desflurane, sevoflurane, propofol on both atrial and ventricular wall function by measurement of QT dispersion (QTd), corrected QT dispersion (QTcd), and P dispersion (Pd) on electrocardiogram (ECG). Forty-six patients from the American Society of Anesthesiologists class I−II undergoing noncardiac surgery, were enrolled in this study. Patients were randomly allocated to receive desflurane, sevoflurane or propofol anesthesia. ECG recordings were taken before and after 5 minutes of drug administration. Induction with desflurane significantly increased the QTd compared to baseline (38 ± 2 ms vs. 62 ± 6 ms, P < 0.05). Sevoflurane and propofol anesthesia was not associated with any changes in QTd. QTcd was increased with desflurane induction and decreased with sevoflurane and propofol induction, but this decrease was only significant in the propofol group (67 ± 5 ms vs. 45 ± 3 ms, P < 0.05). Pd was significantly increased after induction with desflurane (34 ± 3 vs. 63 ± 6 ms, P < 0.05). There was a significant increase in QTd and Pd in desflurane group, but this increment did not cause any dangerous arrhythmias. QTcd significantly decreased in propofol group. We believe that further investigations are required for using desflurane as safe as sevoflurane and propofol in noncardiac surgery patients who have high cardiac arrhythmia and ischemia risk.

Halogenated anaesthetics and cardiac protection in cardiac and non-cardiac anaesthesia.

Volatile anaesthetic agents have direct protective properties against ischemic myocardial damage. The implementation of these properties during clinical anaesthesia can provide an additional tool in the treatment or prevention, or both, of ischemic cardiac dysfunction in the perioperative period. A recent meta-analysis showed that desflurane and sevoflurane reduce postoperative mortality and incidence of myocardial infarction following cardiac surgery, with significant advantages in terms of postoperative cardiac troponin release, need for inotrope support, time on mechanical ventilation, intensive care unit and overall hospital stay. Multicentre, randomised clinical trials had previously demonstrated that the use of desflurane can reduce the postoperative release of cardiac troponin I, the need for inotropic support, and the number of patients requiring prolonged hospitalisation following coronary artery bypass graft surgery either with and without cardiopulmonary bypass. The American College of Cardiology/American Heart Association Guidelines recommend volatile anaesthetic agents during non-cardiac surgery for the maintenance of general anaesthesia in patients at risk for myocardial infarction. Nonetheless, evidence in non-coronary surgical settings is contradictory and will be reviewed in this paper together with the mechanisms of cardiac protection by volatile agents.