Analgaesic Effect of Erector Spinae Plane Block in Coronary Surgery: A Randomised Controlled Trial.

OBJECTIVE: To investigate the effect of preemptive erector spinae plane (ESP) block application on postoperative pain scores and opioid demand in off-pump coronary artery bypass graft (CABG) surgery. STUDY DESIGN: Randomised-controlled trial. Place and Duration of the Study: Department of Anaesthesiology and Reanimation, Abant Izzet Baysal University (AIBU) Medical School, Bolu, Turkiye, from November 2020 to April 2021. METHODOLOGY: Fifty patients between the ages of 50 and 75 years, received CABG surgery. These participants who were at risk of the American Society of Anesthesiologists (ASA) III were randomly divided into two groups: ESP (Group E) and Control (Group C). Intervention in Group E was performed bilaterally at the T5 level before the operation. In the study, the primary outcome was postoperative opioid demand while the secondary outcomes consisted of intraoperative opioid demand, visual analogue scale scores, and the duration of hospital stay. RESULTS: Tramadol demand was significantly decreased in Group E at 0-1, 1-12, 12-24, and 0-48 hours (p <0.05). Intraoperative fentanyl demand for Group E was also statistically significantly decreased (p= 0.001). In Group E, the visual analogue scale scores at 30 minutes, 1st, 2nd, 4th, 8th, 12th hour, and 16th hour after postoperative extubation were observed to be significantly lower than those of Group C (p <0.05). CONCLUSION: Preemptive ESP block application in CABG surgery patients reduced postoperative tramadol demand, intraoperative fentanyl demand, and postoperative pain scores. KEY WORDS: Coronary artery bypass surgery, Erector spinae plane block, Acute postoperative pain.

Effects of Lidocaine Oropharyngeal Spray Applied Before Endotracheal Intubation on QT Dispersion in Patients Undergoing Coronary Artery Bypass Grafting: A Prospective Randomized Controlled Study.

OBJECTIVE: To investigate the effects of lidocaine oropharyngeal spray applied before endotracheal intubation on hemodynamic responses and electrocardiographic parameters in patients undergoing coronary artery bypass grafting. METHODS: A total of 60 patients who underwent coronary artery bypass grafting surgery were included in this prospective randomized controlled study. Patients were randomly divided into two groups, the topical lidocaine group (administration of 10% lidocaine oropharyngeal spray, five minutes before laryngoscopy and endotracheal intubation) and the control group. Both groups were compared with each other in terms of main hemodynamic parameters including mean arterial pressure and heart rate, as well as P and QT wave dispersion durations, before and after endotracheal intubation. RESULTS: The groups were similar in terms of age, gender, and other demographics and basic clinical characteristics. There was a statistically significant difference between the groups in terms of QT dispersion durations after laryngoscopy and endotracheal intubation. The increase in QT dispersion duration was not statistically significant in the topical lidocaine group, whereas the increase in QT dispersion duration was statistically significant in the control group. When the groups were compared in terms of P wave dispersion durations, there were significant decreases in both groups, but there was no significant difference between the groups. CONCLUSION: Our study revealed that the topical lidocaine administration before endotracheal intubation prevented increase of QT dispersion duration in patients undergoing coronary artery bypass grafting. TRIAL REGISTRATION: NCT03304431.

Effects of lidocaine oropharyngeal spray applied before endotracheal intubation on qt dispersion in patients undergoing coronary artery bypass grafting: a prospective randomized controlled study

Abstract Objective: To investigate the effects of lidocaine oropharyngeal spray applied before endotracheal intubation on hemodynamic responses and electrocardiographic parameters in patients undergoing coronary artery bypass grafting. Methods: A total of 60 patients who underwent coronary artery bypass grafting surgery were included in this prospective randomized controlled study. Patients were randomly divided into two groups, the topical lidocaine group (administration of 10% lidocaine oropharyngeal spray, five minutes before laryngoscopy and endotracheal intubation) and the control group. Both groups were compared with each other in terms of main hemodynamic parameters including mean arterial pressure and heart rate, as well as P and QT wave dispersion durations, before and after endotracheal intubation. Results: The groups were similar in terms of age, gender, and other demographics and basic clinical characteristics. There was a statistically significant difference between the groups in terms of QT dispersion durations after laryngoscopy and endotracheal intubation. The increase in QT dispersion duration was not statistically significant in the topical lidocaine group, whereas the increase in QT dispersion duration was statistically significant in the control group. When the groups were compared in terms of P wave dispersion durations, there were significant decreases in both groups, but there was no significant difference between the groups. Conclusion: Our study revealed that the topical lidocaine administration before endotracheal intubation prevented increase of QT dispersion duration in patients undergoing coronary artery bypass grafting. Trial Registration: NCT03304431

An Easy and Reliable Way to Prevent Electrocardiographic Deteriorations of Patients Undergoing Off-Pump Coronary Artery Bypass Surgery: Preoperative Anxiolytic Treatment.

OBJECTIVE: To investigate the effects of preoperative anxiety relieving on electrophysiological changes in patients undergoing off-pump coronary artery bypass surgery. METHODS: A total of 61 patients at ASA III risk group in the age range of 18-65 years were enrolled in the present study. Patients were randomly divided into two groups. Group S (Sedation group) was administered 0.04 mg/kg lorazepam per os (PO) twice before the operation. Group C (control group) was not administered with any anxiolytic premedication. State Trait Anxiety Inventory (STAI-I) and Beck Anxiety Inventory (BAI) were used to evaluate the level of anxiety. Electrocardiography (ECG), pulse oximeter and standard monitoring were performed for each patient. QT and P dispersions in each derivation of all ECGs were calculated. RESULTS: Preoperative STAI-I scores were significantly lower in sedation group compared to the controls. Mean values of QT dispersion measured before induction, at the 1st minute of induction, 30th second of intubation and 4th minute of intubation in sedation group were significantly reduced compared to controls (P=0.024; P=0.027; P=0.001; P=0.033, respectively). The mean values of P dispersion measured before induction, at the 3rd minute of induction, 30th second of intubation and 4th minute of intubation in sedation group were significantly reduced compared to controls (P=0.001; P=0.020; P=0.023; P=0.005, respectively). CONCLUSION: Elevated anxiety levels in patients undergoing coronary bypass surgery have a negative effect through prolonged QT and P-wave dispersion times. Anxiolytic treatment before surgery may be useful to prevent ventricular and atrial arrhythmias and associated complications through decreasing the QT and P-wave dispersion duration.

An easy and reliable way to prevent electrocardiographic deteriorations of patients undergoing off-pump coronary artery bypass surgery: preoperative anxiolytic treatment

Abstract Objective: To investigate the effects of preoperative anxiety relieving on electrophysiological changes in patients undergoing off-pump coronary artery bypass surgery. Methods: A total of 61 patients at ASA III risk group in the age range of 18-65 years were enrolled in the present study. Patients were randomly divided into two groups. Group S (Sedation group) was administered 0.04 mg/kg lorazepam per os (PO) twice before the operation. Group C (control group) was not administered with any anxiolytic premedication. State Trait Anxiety Inventory (STAI-I) and Beck Anxiety Inventory (BAI) were used to evaluate the level of anxiety. Electrocardiography (ECG), pulse oximeter and standard monitoring were performed for each patient. QT and P dispersions in each derivation of all ECGs were calculated. Results: Preoperative STAI-I scores were significantly lower in sedation group compared to the controls. Mean values of QT dispersion measured before induction, at the 1st minute of induction, 30th second of intubation and 4th minute of intubation in sedation group were significantly reduced compared to controls (P=0.024; P=0.027; P=0.001; P=0.033, respectively). The mean values of P dispersion measured before induction, at the 3rd minute of induction, 30th second of intubation and 4th minute of intubation in sedation group were significantly reduced compared to controls (P=0.001; P=0.020; P=0.023; P=0.005, respectively). Conclusion: Elevated anxiety levels in patients undergoing coronary bypass surgery have a negative effect through prolonged QT and P-wave dispersion times. Anxiolytic treatment before surgery may be useful to prevent ventricular and atrial arrhythmias and associated complications through decreasing the QT and P-wave dispersion duration.

Effects of Bispectral Index-controlled Use of Magnesium on Propofol Consumption and Sedation Level in Patients Undergoing Colonoscopy.

OBJECTIVE: The aim of this study is to investigate the effects of bispectral index-controlled use of magnesium on propofol consumption, periprocedural hemodynamic response and patient comfort. MATERIAL: A total of 60 patients were enrolled in the study. In Group 1 (magnesium), a single dose 50 mg/kg magnesium sulfate diluted with 100 mL 0.9% NaCl was administered 10 minutes before the beginning of the procedure. Initially bolus dose of 0.5 mg/kg propofol was applied. The maintenance dose of propofol was 60 mcg/kg/min. During the procedure, the propofol infusion was increased by titration until the bispectral index (BIS) value of 70 was achieved. In Group 2 (saline), 100 ml 0.9% NaCl was administered 10 minutes before the beginning of the procedure. The bolus and maintenance doses of propofol, and target BIS values were the same as those in Group 1. RESULTS: When BIS values were compared between the groups, the initial BIS values in the magnesium group (Group 1) were significantly higher than those of the saline group (Group 2) (p<0.05). The time to reach BIS 70 was significantly shorter in the magnesium group (p<0.05). Propofol consumption was greater in Group 2 than in Group 1 (p<0.05). The time to reach BIS 70 was significantly shorter in Group 1 (p<0.05). No significant difference was found between the groups in terms of patient- and endoscopist-satisfaction (p<0.05). CONCLUSION: The use of magnesium in addition to propofol may be an efficient and reliable option to reduce the drug consumption during colonoscopic interventions.

Effects of minimally invasive decompression surgery on quality of life in older patients with spinal stenosis.

OBJECTIVES: Lumbar spinal stenosis (LSS) in the elderly may result in a progressive narrowing of the spinal canal leading to compression of nerve roots in some individuals. The aim of this study was to evaluate the quality of life changes after minimally invasive decompression surgery without instrumentation in geriatric patients with lumbar spinal stenosis. PATIENTS AND METHODS: This prospective clinical study included 37 patients with American Society of Anesthesiologists (ASA) II-III scores between the ages of 65 and 86 years, who were planned to undergo surgical intervention due to LSS. All patients had neurogenic claudication and pain in the hips, thighs, and legs. Measurements of the osseous spinal canal were evaluated by magnetic resonance imaging. Before the surgical intervention, patient demographics and clinical characteristics were recorded. The Short-Form-36 test, the Oswestry Disability Index, and the Visual Analog Scale were applied to all patients preoperatively and two years postoperatively. RESULTS: In the study population, 11 patients had single level of spinal stenosis, 20 patients had two levels of spinal stenosis, and six patients had three levels of spinal stenosis. There were significant differences between the preoperative and postoperative ODI and VAS scores. There was a statistically significant difference in all subscales of the SF-36 test with the exception of general health scores. Three patients who had dural damage during the operation were treated with bio glue. Also, no patients were recorded to have any neurological deficits and root injuries postoperatively. CONCLUSION: Minimally invasive decompression surgery, without instrumentation, for lumbar spinal stenosis in geriatric patients significantly improves the patients' quality of life.

Colostomy with Transversus Abdominis Plane Block.

Transversus abdominis plane (TAP) block is one of the abdominal field block. The TAP block is used for both anaesthetic management and post-operative pain therapy in lower abdominal surgery. TAP block is a procedure in which local anaesthetic agents are applied to the anatomic neurofacial space between the internal oblique and the transversus abdominis muscle. TAP block is a good method for post-operative pain control as well as allows for short operations involving the abdominal area. In this article, a case of colostomy under TAP block is presented.

[Comparison of the effects of magnesium sulphate and dexmedetomidine on surgical vision quality in endoscopic sinus surgery: randomized clinical study]. / Comparação dos efeitos de sulfato de magnésio e da dexmedetomidina sobre a qualidade da visibilidade em cirurgia endoscópica sinusal: estudo clínico randomizado.

BACKGROUND AND OBJECTIVES: Even a small amount of bleeding during endoscopic sinus surgery can corrupt the endoscopic field and complicate the procedure. Various techniques, including induced hypotension, can minimize bleeding during endoscopic sinus surgery. The aim of this study was to compare the surgical vision quality, haemodynamic parameters, postoperative pain, and other effects of magnesium, a hypotensive agent, with that of dexmedetomidine, which was initially developed for short-term sedation in the intensive care unit but also is an alpha 2 agonist sedative. METHOD: 60 patients between the ages of 18 and 45 years were divided into either the magnesium group (Group M) or the dexmedetomidine group (Group D). In Group M, magnesium sulphate was given at a pre-induction loading dose of 50mgkg(-1) over 10min and maintained at 15mgkg(-1)h(-1); in Group D, dexmedetomidine was given at 1mcgkg(-1) 10min before induction and maintained at 0.6mcgkg(-1)h(-1). Intraoperatively, the haemodynamic and respiratory parameters and 6-point intraoperative surgical field evaluation scale were recorded. During the postoperative period, an 11-point numerical pain scale, the Ramsay sedation scale, the nausea/vomiting scale, the adverse effects profile, and itching parameters were noted. RESULTS: Group D showed a significant decrease in intraoperative surgical field evaluation scale scale score and heart rate. The average operation time was 50min, and Group M had a higher number of prolonged surgeries. No significant difference was found in the other parameters. CONCLUSIONS: Due to its reduction of bleeding and heart rate in endoscopic sinus surgery and its positive impacts on the duration of surgery, we consider dexmedetomidine to be a good alternative to magnesium.

Comparison of the effects of magnesium sulphate and dexmedetomidine on surgical vision quality in endoscopic sinus surgery: randomized clinical study / Comparação dos efeitos de sulfato de magnésio e da dexmedetomidina sobre a qualidade da visibilidade em cirurgia endoscópica sinusal: estudo clínico randomizado / Comparación de los efectos de sulfato de magnesio y dexmedetomidina sobre la calidad de la visibilidad en cirugía endoscópica sinusal: estudio clínico aleatorizado

Background and objectives: Even a small amount of bleeding during endoscopic sinus surgery can corrupt the endoscopic field and complicate the procedure. Various techniques, including induced hypotension, can minimize bleeding during endoscopic sinus surgery. The aim of this study was to compare the surgical vision quality, haemodynamic parameters, postoperative pain, and other effects of magnesium, a hypotensive agent, with that of dexmedetomidine, which was initially developed for short-term sedation in the intensive care unit but also is an alpha 2 agonist sedative. Method: 60 patients between the ages of 18 and 45 years were divided into either the magnesium group (Group M) or the dexmedetomidine group (Group D). In Group M, magnesium sulphate was given at a pre-induction loading dose of 50 mg kg−1 over 10 min and maintained at 15 mg kg−1 h−1; in Group D, dexmedetomidine was given at 1 mcg kg−1 10 min before induction and maintained at 0.6 mcg kg−1 h−1. Intraoperatively, the haemodynamic and respiratory parameters and 6-point intraoperative surgical field evaluation scale were recorded. During the postoperative period, an 11-point numerical pain scale, the Ramsay sedation scale, the nausea/vomiting scale, the adverse effects profile, and itching parameters were noted. Results: Group D showed a significant decrease in intraoperative surgical field evaluation scale scale score and heart rate. The average operation time was 50 min, and Group M had a higher number of prolonged surgeries. No significant difference was found in the other parameters. Conclusions: Due to its reduction of bleeding and heart rate in endoscopic sinus surgery and its positive impacts on the duration of surgery, we consider dexmedetomidine to be a good alternative to magnesium. .

Justificativa e objetivo: Uma quantidade, mesmo pequena, de sangramento durante a cirurgia endoscópica pode alterar o campo endoscópico e dificultar o procedimento. Várias técnicas, incluindo hipotensão induzida, podem minimizar o sangramento durante a cirurgia endoscópica. O objetivo deste estudo foi comparar a qualidade da visibilidade cirúrgica, os parâmetros hemodinâmicos, a dor no período pós-operatório e outros efeitos do sulfato de magnésio, um agente hipotensor, com os da dexmedetomidina, inicialmente desenvolvida para sedação em curto prazo em unidade de terapia intensiva, mas que também é um sedativo agonista alfa-2. Métodos: Foram alocados 60 pacientes entre 18 e 45 anos em dois grupos: Grupo M (magnésio) e Grupo D (dexmedetomidina). No Grupo M, sulfato de magnésio foi administrado pré-indução a uma dose de carga de 50 mg kg−1 por 10 minutos e mantida com 15 mg kg−1 h−1; no Grupo D, dexmedetomidina foi administrada a uma dose de 1 mcg kg−1 10 minutos antes da indução e mantida com 0,6 mcg kg−1 h−1. No período intraoperatório, foram registrados os parâmetros hemodinâmicos e respiratórios e a avaliação do campo cirúrgico com uma escala de seis pontos. Durante o período pós-operatório foram registrados os valores da escala numérica de 11 pontos para avaliar a dor, a escala de sedação de Ramsay, a escala de avaliação de náusea/vômito, o perfil dos efeitos adversos e pruridos. Resultados: O Grupo D apresentou redução significativa da frequência cardíaca e do escore na escala de avaliação do campo cirúrgico intraoperatório. A média do tempo cirúrgico foi de 50 minutos e o Grupo M apresentou um número maior de cirurgias prolongadas. ...

Introducción y objetivo: Una cantidad, aunque sea pequeña, de sangrado durante la cirugía endoscópica puede alterar el campo endoscópico y dificultar el procedimiento. Varias técnicas que incluyen hipotensión inducida pueden minimizar el sangrado durante la cirugía endoscópica. El objetivo de este estudio fue comparar la calidad de la visibilidad quirúrgica, los parámetros hemodinámicos, el dolor en el período postoperatorio y otros efectos del sulfato de magnesio, que es un agente hipotensor, con los de la dexmedetomidina, inicialmente desarrollada para la sedación a corto plazo en la unidad de cuidados intensivos, pero que también es un sedante agonista alfa-2. Método: 60 pacientes con edades entre 18 y 45 años se dividieron en 2 grupos: grupo M (magnesio) y grupo D (dexmedetomidina). En el grupo M, el sulfato de magnesio fue administrado antes de la inducción en dosis de carga de 50 mg kg−1 por 10 min y se mantuvo con 15 mg kg−1 h−1; en el grupo D, la dexmedetomidina fue administrada con una dosis de 1 µg kg−1 durante 10 min antes de la inducción y se mantuvo con 0,6 µg kg−1 h−1. En el período intraoperatorio se registraron los parámetros hemodinámicos y respiratorios y la evaluación del campo quirúrgico con una escala de 6 puntos. Durante el postoperatorio también se registraron la escala numérica de 11 puntos para evaluar el dolor, la escala de sedación de Ramsay, la escala de evaluación de náuseas/vómito, el perfil de los efectos adversos y los pruritos. Resultados: El grupo D tuvo una reducción significativa de la frecuencia cardíaca y de la puntuación en la escala de evaluación del campo quirúrgico intraoperatorio. La media del tiempo quirúrgico fue de 50 min, y el grupo M tuvo un número mayor de ...

Effect of pregabalin and dexamethasone on postoperative analgesia after septoplasty.

Objectives. The aim of this study was to explore effect of a combination of pregabalin and dexamethasone on pain control after septoplasty operations. Methods. In this study, 90 patients who were scheduled for septoplasty under general anesthesia were randomly assigned into groups that received either placebo (Group C), pregabalin (Group P), or pregabalin and dexamethasone (Group PD). Preoperatively, patients received either pregabalin 300 mg one hour before surgery, dexamethasone 8 mg intravenously during induction, or placebo according to their allocation. Postoperative pain treatment included tramadol and diclofenac sodium 30 minutes before the end of the operation. Numeric rating scale (NRS) for pain assessment, side effects, and consumption of tramadol, pethidine, and ondansetron were recorded. Results. The median NRS score at the postoperative 0 and the 2nd h was significantly higher in Group C than in Group P and Group PD (P ≤ 0.004 for both). The 24 h tramadol and pethidine, consumptions were significantly reduced in Groups P and PD compared to Group C (P < 0.001 and P < 0.001). The incidence of blurred vision was significantly higher in Group PD compared to Group C within both 0-2 h and 0-24 h periods (P = 0.002 and P < 0.001, resp.). Conclusions. We conclude that administration of 300 mg pregabalin preoperatively may be an adequate choice for pain control after septoplasty. Addition of dexamethasone does not significantly reduce pain in these patients.

Evaluation of olfactory memory after coronary artery bypass grafting.

INTRODUCTION: This study determined whether coronary artery bypass grafting (CABG) surgery has any effect on olfactory function, employing the Brief Smell Identification Test (B-SIT). MATERIAL AND METHODS: All the participants were informed preoperatively about the B-SIT test and the mode of its application. The test was performed by each patient preoperatively (d0) as well as 1 (d1) and 3 (d3) days following the surgery. C-reactive protein (CRP) levels were recorded at the same time as the smell test. RESULTS: This prospective study included 45 patients. The mean age was 67 ± 7.55, and the group was 29% male. The mean durations of cross clamping and cardiopulmonary bypass were 54 ± 32 min and 62.5 ± 37.0 min, respectively. Eleven different odors were tested. Significant differences were observed for several odors: leather between d0 and d3, pine between d0 and d3, onion between d0 and d1, onion between d0 and d3, and soap between d0 and d1. The postoperative CRP levels were significantly higher than the preoperative levels. The correlation analysis determined that the postoperative CRP levels were negatively correlated with the B-SIT score (r = -0.48, p = 0.001). CONCLUSIONS: Our findings suggest that patients after CABG are prone to develop olfactory dysfunction in the early postoperative period and that olfactory dysfunction is associated with postoperative CRP levels.

Effect of pregabalin and dexamethasone addition to multimodal analgesia on postoperative analgesia following rhinoplasty surgery.

BACKGROUND: We investigated the effect of a combination of pregabalin and dexamethasone, when used as part of a multimodal analgesic regimen, on pain control after rhinoplasty operations. METHODS: Sixty patients were enrolled in this study. They were randomly assigned into three groups: Group C (placebo + placebo), Group P (pregabalin + placebo), and Group PD (pregabalin + dexamethasone). Patients received either pregabalin 300 mg orally 1 h before surgery, dexamethasone 8 mg intravenously during induction, or placebo according to their allocation. Postoperative pain was treated with intravenous patient-controlled analgesia (tramadol, 20-mg bolus dose, 45-min lockout time). The numeric rating scale (NRS), side effects, and consumption of tramadol, pethidine, and ondansetron were assessed. RESULTS: The median NRS scores at 0, 1, and 6 h after surgery were significantly higher in Group C than in Group PD (p < 0.001 for all). The 24-h consumption of tramadol and pethidine was significantly reduced in Groups P and PD compared to Group C (p < 0.01 and p < 0.01). The total tramadol consumption was decreased by 54.5 % in Group P and 81.9 % in Group PD compared to Group C (p < 0.001 for both). The incidence of nausea was higher in Group C than in Groups P and PD between the postoperative 0-2 and 0-24-h periods (p < 0.05 for both). The frequency of blurred vision was significantly higher in Groups P and PD than in Group C within the 0-24-h period (p < 0.05 for both). CONCLUSION: We found that the addition of a single dose of pregabalin and dexamethasone to multimodal analgesia in rhinoplasty surgeries provided efficient analgesia and thus decreased opioid consumption. LEVEL OF EVIDENCE I: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Comparison of the coaxial circle circuit with the conventional circle circuit.

OBJECTIVE: The coaxial circle system helps prevent heat loss during surgery, and it also acts as a humidifier. This study aimed to compare the coaxial breathing system and the conventional system in their ability to warm and moisturize inhaled gases, and we also analyzed lung function protection and saccharin clearance time in patients who underwent tympanomastoidectomy (TMT) with the aid of these two systems. MATERIALS AND METHODS: Forty adult patients of ASA physical status I-II were scheduled for elective TMT. A standard volume-dependent ventilator setting was used to establish normocapnia. The coaxial circle system was used in the treated group (n=20), whereas the conventional circuit system was used in the control group (n=20). Saccharin clearance, VC (vital capacity), FRC (functional residual capacity), FEV1 (forced expiratory volume in 1 second), airway pressure, relative humidity and temperature of inspired gas, body temperature and adverse and hemodynamic effects were measured at different perioperative periods. RESULTS: The relative humidity (mg H2O Lt -1) of inspired gas in the treated group was higher than in the control group at 5, 15, 30, 45, 60 and 90 minutes after anesthesia induction. The temperature of inspired gas (Centigrade) in the treated group was higher than in the control group (p<0.05) after 5, 10, 15, 30, 45, and 90 minutes of anesthesia. Postoperative saccharin clearance time was lower than before the operation in the treated group (p<0.05). Postoperative FRC was lower than preoperative FRC in the study and control groups (p<0.05). CONCLUSION: The coaxial circle system decreased postoperative saccharin clearance time and increased postoperative FRC, relative humidity and the temperature of inspired fresh gas, without any adverse perioperative effects in patients who underwent TMT.