Clinical trial NCT03946657: Anesthetics and Cerebral Oxygenation in LSG
Official title: A Comparison of Cerebral Oximetry After Propofol-Based Total Intravenous Anesthesia and Sevoflurane Inhalation Anesthesia in Morbidly Obese Patients Undergoing LSG: a Prospective, Single-Blinded, Randomized, Parallel-Group Study.
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE4
Conditions: Morbid Obesity
Bariatric Surgery Candidate
Anesthesia
Keywords: Bariatric
Surgery
Sevoflurane
Propofol
Oximetry
Lead sponsor: Ondokuz Mayıs University
Sponsor class: OTHER
First posted: 2019-05-10
Enrollment: 60
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: For the investigation, the patients were randomly assigned to two groups; the Inhalation group including those who received sevoflurane-remifentanil for the maintenance of anesthesia (n = 30) and the TIVA (total intravenous anesthesia) group including those who had propofol-remifentanil infusion for the maintenance of anesthesia (n = 30). The anesthesiologist caring for the patient was aware of the group assignments. The patients were blinded to the group assignments.
Primary purpose: SUPPORTIVE_CARE

Brief summary: Obesity is a global health issue that affects different organ systems and may cause severe health issues. Patients with a BMI \> 40 kg/m2 or those with a BMI \> 35 kg/m2 with accompanying comorbidities are candidates for weight loss surgeries, which are generally referred to as bariatric surgeries. Laparoscopic sleeve gastrectomy (LSG) is a restrictive bariatric surgery procedure gaining increased popularity in the surgical treatment of morbid obesity. However, LSG requires a reverse-Trendelenburg position and prolonged pneumoperitoneum. Carbon dioxide pneumoperitoneum increases intracranial pressure (ICP) by increasing intra-abdominal pressure and by causing dilation of cerebral vessels through carbon dioxide reabsorption. Also, the reverse-Trendelenburg position decreases cardiac output and mean arterial pressure (MAP) by reducing cardiac venous return. A Near-infrared spectroscopy (NIRS) is a non-invasive technique and provides continuous monitoring of regional cerebral tissue oxygen saturation (rSO2).

Sevoflurane and propofol are widely used for the maintenance of general anesthesia during bariatric surgery. Sevoflurane is an efficacious halogenated inhalational anesthetic for bariatric surgery because of its rapid and consistent recovery and because it does not cause hemodynamic instability because of its low blood solubility. Moreover, it increases global CBF through a direct intrinsic cerebral vasodilatory action and, in addition, it might improve cerebral oxygenation by decreasing the cerebral metabolic rate of oxygen (CMRO2) (luxury perfusion). Propofol can also be a suitable option for the maintenance of anesthesia in bariatric surgery. Propofol is a short-acting intravenous anesthetic agent with a very good recovery profile, and its elimination half-life and duration of action do not change in obese individuals. However, it has been reported that propofol may significantly decrease CBF by both suppressing CMRO2 and through a direct vasoconstrictive action. The impact of propofol on global CBF is more salient than that on CMRO2, resulting in a decrease in rSO2. The aim of the present study was to test the hypothesis that rSO2 is better preserved with sevoflurane than propofol in morbidly obese patients who have undergone LSG.

Detailed description: All patients were administered 300 mg of oral ranitidine the night before the surgery and 10 mg intravenous (IV) metoclopramide in combination with 150 mg ranitidine one hour before arrival to the operating room. Upon the arrival to the operating room, an electrocardiogram, noninvasive blood pressure, SpO2, rSO2 (INVOSTM 5100C oximeter; Covidien, Massachusetts, USA) and neuromuscular monitorization (TOF-WatchTM SX, Organon, Dublin, Ireland) were performed on the patients. Afterwards, preoxygenation was performed with 4 L/min oxygen (80%) for three minutes by using facemasks, and anesthesia was induced with an IV propofol injection (1.5-2.5 mg/kg of ideal body weight) and an IV bolus administration of remifentanil \[1 mcg/kg of lean body weight (LBW)\] for 30-60 s, and then switched to infusion at 0.25 mcg/kg of LBW/min. After the eyelid reflex disappeared, a neuromuscular blockade was performed using rocuronium (1.2 mg/kg of LBW), ensuring that the train-of-four count and the post-tetanic count (PTC) were both zero, and performed tracheal intubation. Mechanical ventilation was performed with a Draeger FabiusTM Plus anesthesia workstation (Draeger Medical, Lübeck, Germany), and volume-controlled mechanical ventilation was applied. Breathing gases (oxygen, carbon dioxide, sevoflurane) were measured using Draeger ScioTM gas measurement module (Draeger Medical, Lübeck, Germany). The tidal volume was set as 7-8 mL/kg of LBW, inspiratory: expiratory ratio as 1:2, positive end-expiratory pressure as 5-8 cmH2O, and the respiratory rate was determined to obtain an end-tidal carbon dioxide partial pressure (PETCO2) of 32-37 mmHg. These ventilator settings were not changed throughout the operation. Furthermore, after the induction of anesthesia, a radial arterial line was placed in all patients for the continuous measurement of mean arterial pressure and intermittent arterial blood gas analysis.

Oxygen/air (fraction of inspired oxygen (FiO2) of 0.40), inspiratory fresh gas flow of 2 L/min), sevoflurane (1 minimum alveolar concentration \[MAC\]) and remifentanil IV infusion (0.1-0.25 mcg/kg of LBW/min) were used in the Inhalation group for the maintenance of anesthesia. Propofol infusion (4-8 mg/kg of total body weight/h), oxygen/air (FiO2 of 0.40; inspiratory fresh gas flow of 2 L/min) and remifentanil IV infusion (0.1-0.25 μg/kg of LBW/min) were used in the TIVA group. Neuromuscular blockade was performed during the operation by rocuronium infusion (0.3-0.7 mg/kg of LBW/h), ensuring that PTC was zero. IV normal saline or lactated Ringer's solution at 5-7 mL/kg of LBW was also used for perioperative fluid maintenance. Nasopharyngeal temperature was monitored throughout the surgery, and the patient temperature (36-37°C) was ensured by using a forced-air warming system for the maintenance of intraoperative normothermia during the procedure.

After anesthesia induction, a neutral head position of the patients was preserved to prevent alteration of cerebral venous drainage. Carbon dioxide insufflation was performed with an electronic laparoflator using a closed Veress needle technique, and intra-abdominal pressure was automatically kept at the desired level (14-16 mmHg) during the surgery. After the insufflation of carbon dioxide, the patients were positioned in a 30° reverse-Trendelenburg and at a 10° right lateral position.

At the end of the surgery, the blockade was reversed by administering 4 mg/kg of adjusted body weight sugammadex with a PTC of 1-2. All patients were extubated in the beach chair position when fully awake. The patients were referred to the recovery unit and monitored for 50 minutes for complications. In cases where no complications were apparent, the recovery was evaluated using the modified Aldrete scoring system. Once the score was ≥9, the patients were taken to unit. For postoperative nausea and vomiting, 4-5 mg dexamethasone was used (except for diabetic patients on insulin) 90 min before anesthesia induction and 4-8 mg IV ondansetron 20-30 min before the end of the operation. For postoperative pain management, 1 g IV acetaminophen was administered 20 min after induction and 30 mg IV ketorolac 20 min before onset. Then, 1 g IV acetaminophen was administered every 6 h + 50 mg IV dexketoprofen every 8 h for the first 48 hours. In addition, morphine was administered using a patient-controlled analgesia delivery system (demand dose, 20 µg/kg of ideal body weight; lockout time, 6-10 min; 4 h limit, 80% of the total calculated dosage) for 48 h postoperatively.

Eligibility criteria: Inclusion Criteria:

* The American Society of Anaesthesiologists (ASA) physical status class II-III
* BMI of ≥ 35 kg/m2
* Patients were planning on undergoing an elective laparoscopic sleeve gastrectomy (LSG)

Exclusion Criteria:

* Patients with preexisting cerebrovascular diseases, overt neurological signs, alcohol or psychoactive drug addiction
* Uncontrolled diabetes or hypertension
* Advanced organ failure
* Preoperative peripheral oxygen saturation (SpO2) less than 96%
* Hemoglobin \<9 g/dL .

Primary outcomes:
measure: Cerebral oxygen saturation
timeFrame: The rSO2 values of the patients were recorded from baseline untill 20 minutes after the extubation, up to 120 min.
measure: Arterial Blood Gas (ABG) analysis-pH
timeFrame: The pH values of the patients were recorded after anesthesia induction until the patient was referred to the recovery unit, up to 120 min.
measure: Arterial Blood Gas (ABG) analysis-Partial pressure of carbon dioxide
timeFrame: The partial pressure of carbon dioxide values of the patients were recorded after anesthesia induction until the patient was referred to the recovery unit, up to 120 min.
measure: Arterial Blood Gas (ABG) analysis-Hemoglobin
timeFrame: The hemoglobin values of the patients were recorded after anesthesia induction until the patient was referred to the recovery unit, up to 120 min.
Secondary outcomes:
measure: The heart rate (HR) measurement
timeFrame: The heart rate was recorded from baseline until the patient was referred to the recovery unit, up to 120 min.
measure: The oxygen saturation measurement
timeFrame: The oxygen saturation was recorded from baseline until the patient was referred to the recovery unit, up to 120 min.
measure: The mean arterial pressure measurement
timeFrame: The mean arterial pressure was recorded from baseline until the patient was referred to the recovery unit, up to 120 min.
measure: The end-tidal carbon dioxide partial pressure measurement
timeFrame: The end-tidal carbon dioxide partial pressure was recorded from baseline until the patient was referred to the recovery unit, up to 120 min.
measure: The anesthesia time (min)
timeFrame: The anesthesia time was recorded through study completion.
measure: The reverse-Trendelenburg time (min)
timeFrame: The reverse-Trendelenburg time was recorded through study completion.
measure: The pneumoperitoneum time (min)
timeFrame: The pneumoperitoneum time was recorded through study completion.
measure: The recovery time (min)
timeFrame: The recovery time was recorded at the end of the surgery untill the extubation.
Other outcomes:
Locations:
city: Samsun
country: Turkey
facility: Ondokuz Mayis Universitesi
state: Atakum
Study officials:
affiliation: Ondokuz Mayis University, School of Medicine, Department of Anesthesiology
name: CENGIZ KAYA, Assoc. Prof.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Soleimanpour H, Safari S, Sanaie S, Nazari M, Alavian SM. Anesthetic Considerations in Patients Undergoing Bariatric Surgery: A Review Article. Anesth Pain Med. 2017 Jul 11;7(4):e57568. doi: 10.5812/aapm.57568. eCollection 2017 Aug.
citation: Schofield DL, Morton PG, Brokos C, Gruel R, Johannes S, McBride N, et al. Perioperative Assessment and Risk Stratification of the Obese Patient. Bariat Nurs Surg Pat 2011;6:201 - 206.
citation: Himpens J, Dobbeleir J, Peeters G. Long-term results of laparoscopic sleeve gastrectomy for obesity. Ann Surg. 2010 Aug;252(2):319-24. doi: 10.1097/SLA.0b013e3181e90b31.
citation: Yorulmaz IS, Demiraran Y, Salihoglu Z, Umutoglu T, Ozaydin I, Dogan S. Effect of PEEP, Zero PEEP and Intraabdominal Pressure Levels on Cerebral Oxygenation in the Morbidly Obese Undergoing Sleeve Gastrectomy. Bariatr Surg Pract P 2017;12:123 - 129.
citation: Willeumier KC, Taylor DV, Amen DG. Elevated BMI is associated with decreased blood flow in the prefrontal cortex using SPECT imaging in healthy adults. Obesity (Silver Spring). 2011 May;19(5):1095-7. doi: 10.1038/oby.2011.16. Epub 2011 Feb 10.
citation: Sollazzi L, Perilli V, Modesti C, Annetta MG, Ranieri R, Tacchino RM, Proietti R. Volatile anesthesia in bariatric surgery. Obes Surg. 2001 Oct;11(5):623-6. doi: 10.1381/09608920160557138.
citation: Kaisti KK, Langsjo JW, Aalto S, Oikonen V, Sipila H, Teras M, Hinkka S, Metsahonkala L, Scheinin H. Effects of sevoflurane, propofol, and adjunct nitrous oxide on regional cerebral blood flow, oxygen consumption, and blood volume in humans. Anesthesiology. 2003 Sep;99(3):603-13. doi: 10.1097/00000542-200309000-00015.
citation: Servin F, Farinotti R, Haberer JP, Desmonts JM. Propofol infusion for maintenance of anesthesia in morbidly obese patients receiving nitrous oxide. A clinical and pharmacokinetic study. Anesthesiology. 1993 Apr;78(4):657-65. doi: 10.1097/00000542-199304000-00008.
citation: Engelhard K, Werner C. Inhalational or intravenous anesthetics for craniotomies? Pro inhalational. Curr Opin Anaesthesiol. 2006 Oct;19(5):504-8. doi: 10.1097/01.aco.0000245275.76916.87.
citation: Honca M, Honca T. Comparison of Propofol with Desflurane for Laparoscopic Sleeve Gastrectomy in Morbidly Obese patients: A Prospective Randomized Trial. Bariatr Surg Pract P 2017;12:49 - 54.
citation: Reinsfelt B, Westerlind A, Ricksten SE. The effects of sevoflurane on cerebral blood flow autoregulation and flow-metabolism coupling during cardiopulmonary bypass. Acta Anaesthesiol Scand. 2011 Jan;55(1):118-23. doi: 10.1111/j.1399-6576.2010.02324.x. Epub 2010 Oct 7.
citation: Dagal A, Lam AM. Cerebral autoregulation and anesthesia. Curr Opin Anaesthesiol. 2009 Oct;22(5):547-52. doi: 10.1097/ACO.0b013e32833020be.
citation: Klein KU, Schramm P, Glaser M, Reisch R, Tresch A, Werner C, Engelhard K. Intraoperative monitoring of cerebral microcirculation and oxygenation--a feasibility study using a novel photo-spectrometric laser-Doppler flowmetry. J Neurosurg Anesthesiol. 2010 Jan;22(1):38-45. doi: 10.1097/ANA.0b013e3181bea439.
citation: Klein KU, Fukui K, Schramm P, Stadie A, Fischer G, Werner C, Oertel J, Engelhard K. Human cerebral microcirculation and oxygen saturation during propofol-induced reduction of bispectral index. Br J Anaesth. 2011 Nov;107(5):735-41. doi: 10.1093/bja/aer227. Epub 2011 Jul 31.
citation: Jeong H, Jeong S, Lim HJ, Lee J, Yoo KY. Cerebral oxygen saturation measured by near-infrared spectroscopy and jugular venous bulb oxygen saturation during arthroscopic shoulder surgery in beach chair position under sevoflurane-nitrous oxide or propofol-remifentanil anesthesia. Anesthesiology. 2012 May;116(5):1047-56. doi: 10.1097/ALN.0b013e31825154d2.
citation: Valencia L, Rodriguez-Perez A, Kuhlmorgen B, Santana RY. Does sevoflurane preserve regional cerebral oxygen saturation measured by near-infrared spectroscopy better than propofol? Ann Fr Anesth Reanim. 2014 Apr;33(4):e59-65. doi: 10.1016/j.annfar.2013.12.020. Epub 2014 Feb 24.
citation: Ruzman T, Simurina T, Gulam D, Ruzman N, Miskulin M. Sevoflurane preserves regional cerebral oxygen saturation better than propofol: Randomized controlled trial. J Clin Anesth. 2017 Feb;36:110-117. doi: 10.1016/j.jclinane.2016.10.010. Epub 2016 Dec 1.
citation: Sen P, Izdes S, But A. Effects of sevoflurane and propofol anaesthesia on cerebral oxygenation during normocapnia and mild hypercapnia: a pilot study. Br J Anaesth. 2013 Feb;110(2):318-9. doi: 10.1093/bja/aes489. No abstract available.