The role of entropy monitoring in reducing propofol requirements during open heart surgeries. A prospective randomized study.

Background: Hypotension, which is commonly associated with propofol induction of general anesthesia in coronary artery bypass grafting (CABG) surgery, may cause adverse consequences in patients with coronary artery diseases undergoing this type of surgeries. The clinical absence of verbal response and eyelash reflex was used as an endpoint for hypnosis. Spectral entropy, as a novel monitoring method for the endpoint of hypnosis, affect the dose of required anesthetic agents for induction as well as the hemodynamic profile during general anesthesia in CABG surgery. Aims: We hypothesized that entropy monitoring might reduce the dose of propofol required for induction of anesthesia during CABG surgery and could maintain hemodynamic stability when compared with the conventional clinical monitoring. Materials and Methods: Sixty adult patients of both sexes, aged 30-60 years, ASA II and III, and scheduled for CABG surgery were enrolled in this prospective, controlled, randomized, double-blind study. These patients were randomly divided into two equal groups to receive intravenous propofol for induction of anesthesia guided by either the patients' clinical response (Group I) or by entropy monitoring (Group II). The total dose of propofol used for induction of anesthesia was recorded. Hemodynamic parameters and entropy values were also recorded. Results: Propofol consumption was significantly reduced in Group II than Group I (P = 0.000*). Heart rate showed no statistical significance between the two groups, whereas the mean arterial pressure significantly decreased at induction in group I compared to Group II (P = 0.000*). The entropy values were significantly lower in Group I than Group II at induction (P = 0.036* for state entropy; 0.002* for response entropy). However, during intubation, and after 1 and 5 min, entropy indices displayed a significant increase in Group I than Group II. Conclusions: Entropy monitoring significantly reduced the dose of propofol required for induction of anesthesia and maintained hemodynamic stability compared to the conventional clinical monitoring during CABG surgeries.

Cardioprotective effects of propofol-dexmedetomidine in open-heart surgery: A prospective double-blind study.

Background: Myocardial protection in cardiac surgeries is a must and requires multimodal approaches in perioperative period to decrease and prevent the increase of myocardial oxygen demand and consumption that lead to postoperative cardiac complications including myocardial ischemia, dysfunction, and heart failure. Study Design: Prospective, controlled, randomized, double-blinded study. Aims: This study aims to study the effect of propofol-dexmedetomidine continuous infusion cardioprotection during open-heart surgery in adult patients. Materials and Methods: Sixty adult patients of both sexes aged from 30 to 60 years old belonging to the American Society of Anesthesiologists III or IV undergoing open-heart surgery were randomly divided into two equal groups: Group P (control group) received continuous infusion of propofol at a rate of 2 mg/kg/h and 50 cc 0.9% sodium chloride solution infused at a rate of 0.4 µg/kg/h (used as a placebo) and Group PD received continuous infusion of propofol at a rate of 2 mg/kg/h and dexmedetomidine 200 µg diluted in 50 cc 0.9% sodium chloride solution infused at a rate of 0.4 µg/kg/h. Infusion for all patients started immediately preoperative till skin closure. Hemodynamic measurements of heart rate (HR), invasive mean arterial pressure, and oxygen saturation were recorded at baseline before induction of anesthesia, immediately after intubation, at skin incision, at sternotomy and every 15 min in the 1st h then every 30 min during the prebypass period then every 15 min in the 1st h then every 30 min after weaning from CPB till the end of the surgery. Serum biomarkers; cardiac troponin (cTnI) and creatine kinase-myocardial bound (CK-MB) samples were measured basally (T1), 15 min after unclamping of the aorta (T2), immediate postoperative (T3), and 24 h postoperative (T4). Intraoperative data were also recorded including the number of coronary grafts, aortic cross-clamping duration, duration of cardiopulmonary bypass (CPB), duration of surgery, and rhythm of reperfusion. Fentanyl requirement, extubation time, and length of intensive care unit (ICU) stay were also recorded for every case. Results: There was no statistically significant differences as regard to demographic data between the studied two groups. HR and blood pressure recorded was lower in the PD group than the control group, and this difference was noted to be statistically significant. Furthermore, the PD group showed lower levels of myocardial enzymes (cTnI and CK-MB), decreased total fentanyl requirement, earlier postoperative extubation, and shorter ICU stay than the P(control) group. Conclusion: The use of propofol-dexmedetomidine in CPB surgeries offers more cardioprotective effects than the use of propofol alone.

Vasopressin Continuous Infusion Improves Intracranial Pressure and Patient Outcomes after Surgical Clipping or Endovascular Coiling of Cerebral Aneurysm.

BACKGROUND: Hypertensive therapy prevents vasospasm-related delayed ischemic neurologic deficit and infarcts. New alternatives would include vasopressin which has vasoconstrictive effects and positive influence on cerebral perfusion pressure (CPP) and intracranial pressure (ICP). AIMS: The aim of this study is to demonstrate the value of vasopressin intravenous infusion (IVI) in decreasing ICP and preventing vasospasm following surgical clipping or endovascular coiling. SETTINGS AND DESIGN: A triple-blind prospective randomized controlled study. SUBJECTS AND METHODS: Thirty patients, 25-60 years, both genders, had undergone surgical clipping or endovascular coiling for a cerebral aneurysm, World Federation of Neurosurgical Societies (WFNS) grade 1-3 (15 patients in each); Group I (Vasopressin): 0.1-0.4 unit/min and Group II (Norepinephrine): 5-20 ug/min with target systolic blood pressure 160-180 mmHg. STATISTICAL ANALYSIS: SPSS version 25 software was used for analysis. RESULTS: Invasive mean arterial pressure (MAP) showed the insignificant difference between the two groups, but ICP showed a significant decrease in Group V from hour 24 to 168 hence calculated CPP showed a significant increase in Group V at most times from hour 36 to 168. Glasgow Coma Scale showed a significant decrease in Group N from hour 138 due to the occurrence of vasospasm. The incidence of vasospasm, mechanical ventilation, and 28-day mortality were significantly lower in Group V with 81% risk reduction of vasospasm and better survival. CONCLUSION: Vasopressin IVI improved ICP, MAP, CPP and patient outcomes safely by reducing the incidence of cerebral vasospasm, and 28-day mortality after clipping or coiling of the cerebral aneurysm.

Evaluation of local intra-pleural application of tranexamic acid on postoperative blood loss in lung decortication surgery, a prospective, randomized, double-blind, placebo-controlled study.

Background: During decortication surgery, fibrous peel over the lung was removed to allow expansion of the lung and therefore, wide raw area was created with surface oozing. The phenomenon of fibrinolysis usually activated after such procedure, resulting in increasing the postoperative bleeding. Tranexamic acid is one of antifibrinolytic therapies that could be used topically and to targets directly the source of bleeding and reducing the local activation of the fibrinolytic process and consequently reducing the postoperative bleeding. Patients and Methods: A total of 70 patients underwent lung decortication surgery in Cardiothoracic Surgery Department at Tanta University Hospital from January 2015 to May 2017. Patients were randomly allocated into two groups, Group I (35 patients) receiving 3 g of tranexamic acid in 100 ml of saline solution and Group II (35 patients) receiving 100 ml of saline solution as placebo. At the end of the operation and before closing the chest, in both groups, drug or placebo solution was distributed locally all over the pleural cavity. Comparison between the groups was done regarding the amount of postoperative bleeding, postoperative hemoglobin in the first 24 and 48 h postoperatively, blood transfusion, Intensive Care Unit (ICU) stay, and hospital stay. Results: Both groups were comparable regarding demographic and surgical data. Group I patients had the significantly lesser amount of postoperative blood loss than Group II during the first postoperative 48 h, and hence, the need of postoperative blood transfusion was significantly lower in Group I with better postoperative hemoglobin level than Group II. However, there was no difference in overall ICU and hospital stay. Conclusion: The local intrapleural use of tranexamic acid after decortication surgery of the lung is safe and significantly reduces the amount of postoperative blood loss and in consequence reduces the amount of postoperative blood transfusion.

Sedation effects by dexmedetomidine versus propofol in decreasing duration of mechanical ventilation after open heart surgery.

OBJECTIVE: : The objective of this study was to compare the suitability (efficacy and safety) of dexmedetomidine versus propofol for patients admitted to the intensive care unit (ICU) after the cardiovascular surgery for the postoperative sedation before weaning from mechanical ventilation. BACKGROUND: Sedation is prescribed in patients admitted to the ICU after cardiovascular surgery to reduce the patient discomfort, ventilator asynchrony, to make mechanical ventilation tolerable, prevent accidental device removal, and to reduce metabolic demands during respiratory and hemodynamic instability. Careful drug selection for sedation by the ICU team, postcardiovascular surgery should be done so that patients can be easily weaned from mechanical ventilation after sedation is stopped to achieve a shorter duration of mechanical ventilation and decreased the length of stay in ICU. METHODS: A total of 50 patients admitted to the ICU after cardiovascular surgery, aged from 18 to 55 years and requiring mechanical ventilation on arrival to the ICU were enrolled in a prospective and comparative study. They were randomly divided into two groups as follows: Group D patients (n = 25) received dexmedetomidine in a maintenance infusion dose of 0.8 µg/kg/h and Group P patients (n = 25) received propofol in a maintenance infusion dose of 1.5 mg/kg/h. The patients were assessed for 12 h postoperatively, and dosing of the study drug was adjusted based on sedation assessment performed with the Richmond Agitation-Sedation Scale (RASS). The patients were required to be within the RASS target range of -2 to +1 at the time of study drug initiation. At every 4 h, the following information was recorded from each patient such as heart rate (HR), mean arterial pressure (MAP), arterial blood gases (ABG), tidal volume (TV), exhaled TV, maximum inspiratory pressure, respiratory rate and the rapid shallow breathing index, duration of mechanical ventilation, midazolam and fentanyl dose requirements, and financial costs. RESULTS: The study results showed no statistically significant difference between both groups with regard to age and body mass index. Group P patients were more associated with lower MAP and HR than Group D patients. There was no statistically significant difference between groups with regard to ABG findings, oxygenation, ventilation, and respiratory parameters. There was significant difference between both the groups in midazolam and fentanyl dose requirement and financial costs with a value of P < 0.05. CONCLUSION: Dexmedetomidine is safer and equally effective agent for the sedation of mechanically ventilated patients admitted to the ICU after cardiovascular surgery compared to the patients receiving propofol, with good hemodynamic stability, and equally rapid extubation time.

Does the Use of Nitroglycerin Patch Improve Local Anaesthetic Effects in Bier's Block? A Double-Blind Placebo Controlled Study.

AIM: The aim of the study was to assess the nitroglycerin patch as a new additive to Bier's block and its impact on the effects and dose of lidocaine. METHODS: Forty patients of each sex belonging to ASA I or II underwent elective tendon repair surgeries of the forearm and hand. The patients were divided into two equal groups as follows: Group C received only lidocaine (1.5 mg/kg, 0.25%) and Group N received lidocaine (1.5 mg/kg, 0.25%) + 5 mg transcutaneous nitroglycerin patch. Onset and recovery times for sensory and motor block, visual analogue scale (VAS) scores for bandage pain, postoperative VAS score, analgesic requirements, patients' satisfaction, and surgeons' opinion were recorded. RESULTS: Sensory block onset time was shorter in Group N (3.80 ± 1.0) than that in Group C (5.72 ± 1.46), and motor block onset time was shorter in Group N (10.72 ± 1.93) than that in Group C (13.56 ± 1.26). Sensory block recovery time was prolonged in Group N (10.56 ± 1.12) than Group C (6.88 ± 1.45), recovery time of motor block was prolonged in Group N (13.04 ± 1.57) than Group C (11.96 ± 1.72). Bandage pain had lower VAS scores in Group N. Postoperative VAS scores showed significant differences between both groups at the following points of measurement: 30 minutes, 1 hour, and 4 hours after bandage deflation. Postoperative analgesic effect was the longest in Group N (187.20 ± 60.79 min) than Group C (51.60 ± 25.28 min). Patients' satisfaction and surgeons' opinion were better in Group N than Group C. CONCLUSION: Supplementation of Bier's block with transcutaneous nitroglycerin patch reduces the lidocaine dose, the sensory and motor block onset times, VAS scores, and analgesic consumption intra- and postoperatively. Length of the block recovery times for the sensory and motor effects, duration of postoperative analgesic effect, and the first time to analgesic requirement improved the quality of Bier's block with better patients' satisfaction and surgeons' opinion and had no adverse effects.

Does bilevel positive airway pressure improve outcome of acute respiratory failure after open-heart surgery?

BACKGROUND: Respiratory failure is of concern in the postoperative period after cardiac surgeries. Invasive ventilation (intermittent positive pressure ventilation [IPPV]) carries the risks and complications of intubation and mechanical ventilation (MV). AIMS: Noninvasive positive pressure ventilation (NIPPV) is an alternative method and as effective as IPPV in treating insufficiency of respiration with less complications and minimal effects on respiratory and hemodynamic parameters next to open-heart surgery. DESIGN: This is a prospective, randomized and controlled study. MATERIALS AND METHODS: Forty-four patients scheduled for cardiac surgery were divided into two equal groups: Group I (IPPV) and Group II (NIPPV). Heart rate (HR), mean arterial pressure (MAP), respiratory rate (RR), oxygen saturation (SpO2), arterial blood gas, weaning time, reintubation, tracheotomy rate, MV time, postoperative hospital stay, and ventilator-associated pneumonia during the period of hospital stay were recorded. RESULTS: There was statistically significant difference in HR between groups with higher in Group I at 30 and 60 min and at 12 and 24 h. According to MAP, it started to increase significantly at hypoxemia, 15 min, 30 min, 4 h, 12 h, and at 24 h which was higher in Group I also. RR, PaO2, and PaCO2showed significant higher in Group II at 15, 30, and 60 min and 4 h. According to pH, there was a significant difference between groups at 15, 30, and 60 min and at 4, 12, and 24 h postoperatively. SpO2showed higher significant values in Group I at 15 and 30 min and at 12 h postoperatively. Duration of postoperative supportive ventilation was higher in Group I than that of Group II with statistically significant difference. Complications were statistically insignificant between Group I and Group II. CONCLUSION: Our study showed superiority of invasive over noninvasive mode of ventilator support. However, NIPPV (bilevel positive airway pressure) was proved to be a safe method.

Is I-gel airway a better option to endotracheal tube airway for sevoflurane-fentanyl anesthesia during cardiac surgery?

BACKGROUND: Anesthetists used lower doses of fentanyl, successfully with hemodynamic control by titrating volatile anesthetic agents or vasodilators for fast-tracking in cardiac surgery. HYPOTHESIS: Lower total doses of anesthetics and fentanyl could be required with hemodynamic control by use of supraglottic devices than endotracheal tube (ETT) and helps in fast-tracking. DESIGN: A prospective randomized observational clinical trial study. AIMS: The authors compared the utility of I-gel airway with a conventional ETT during the induction and maintenance of anesthesia with sevoflurane and fentanyl in adults undergoing cardiac surgery. PATIENTS AND METHODS: A total of 49 adult patients underwent cardiac surgery were randomized into two groups according to the airway management: I-gel group (n = 23) and ETT group (n = 26). Doses of fentanyl and hemodynamic parameters (heart rate [HR], mean arterial pressure [MAP] central venous pressure [CVP], pulmonary artery pressure [PAP], and pulmonary capillary wedge pressure [PCWP]) were recorded preoperative, 5 min following tracheal intubation or I-gel airway insertion, after skin incision, after stenotomy, and after weaning off bypass. RESULTS: None of the patients in the I-gel group required additional doses of fentanyl during the I-gel insertion, compared with 74% of the patients during laryngoscopy and endotracheal insertion in the ETT group, for an average total dose of 22.6 ± 0.6 µg/kg. The MAP and HR did not significantly differ from the baseline values at any point of measurement in either group. Furthermore, CVP, PAP, and PCWP measured during the procedure were significantly lower in I-gel group than ETT group. Extubation required more amount of time in ETT than I- gel group. CONCLUSION: The I-gel airway is well-tolerated by adult patients undergoing cardiac surgery, and requires lower total doses of anesthetics than endotracheal intubation with hemodynamic control and helps in fast-tracking.

Facilitation of fiberoptic nasotracheal intubation with magnesium sulfate: A double-blind randomized study.

BACKGROUND: A double-blinded, prospective, and randomized study was designed to determine the efficacy and tolerability of intravenous (IV) magnesium sulfate (MgSO4) to facilitate fiberoptic bronchoscopic (FOB) nasotracheal intubations. PATIENTS AND METHODS: A total of 120 patients scheduled to undergo elective awake fiberoptic nasotracheal intubation, while they were anesthetized for elective surgery were randomly allocated to one of three groups: The control Group S (n = 40) received 100 ml (50 ml 0.9% saline + 50 ml paracetamol) was infused in 10 min and direct IV 5 ml 0.9% normal saline, Group MD (n = 40): Received midazolam IV in a dose of 0.07 mg/kg in 5 ml 0.9% normal saline and 100 ml 0.9% was infused in 10 min and Group MS (n = 40): IV 45 mg/kg MgSO4 10 min in 100 ml of 0.9% normal saline through 10 min and direct IV 5 ml 0.9% normal saline. RESULTS: Time required for nasotracheal intubation was significantly less in group Groups MD and MS, as compared with the control group, but not significant between the two groups. (Group MD: 9.05 + 1.95 min, Group MS 3.75 + 0.75 min and Group S 16.85 + 1.7 min). However, the number of fiberoptic intubation was significantly more in the MD and MS groups, as compared with the control group. Easy intubation (control group: 0, Group MD: 25 and Group MS: 35), moderate difficulty (control group: 5, Group MD: 12 and Group MS: 4) and difficult (control group: 35, Group MD: 3 and Group MS: 1). Procedure adverse events were significantly lower in Group MS. None of the patients in Group MS had procedure hypoxia, but it occurred in 10 patients of Group MD and 20 patients in Group S. Six patients in Group S and two in Group MD had procedure apnea whereas, none of the patients in the MS group experienced this. After medication and just before intubation heart rate and mean arterial pressure were significantly less in Groups MD and MS, as compared to the control group (Group MD: 77 + 7.7 beat/min, Group MS: 70 + 5.6 beat/min and Group S: 80 + 7.8 beat/min) (Group MD: 90 + 8.5 mmHg, Group MS: 80 + 8.1 mmHg and Group S: 105 + 10.5 mmHg). This difference however, significant between Group MD and Group MS. CONCLUSION: Intravenous MgSO4 improved awaken FOB intubation without adverse hemodynamic or respiratory effects.

Infusion of low-dose vasopressin improves left ventricular function during separation from cardiopulmonary bypass: a double-blind randomized study.

We aimed to investigate whether low-dose vasopressin administered to patients undergoing coronary artery bypass grafting (CABG) surgery with preexisting mild to moderate systolic dysfunction can produce sustained improvement in cardiac function. This double-blind randomized study was conducted in a hospital where a single anesthetic and surgical team performed elective CABG. Twenty patients aged 32-61 years who underwent elective CABG between January 2007 and December 2007 were enrolled in this study. The patients randomly received either vasopressin 0.03 IU/min (Group A) or normal saline (Group B) in equal volume for 60 min after cardiopulmonary bypass (CPB). The cardiac output, cardiac index, stroke volume index, fractional area of contraction and systemic vascular resistance index were significantly higher in Group A than in Group B. Adrenaline (mean dose: 0.06 µg/kg x min-1) was required in seven patients from Group B but in none of the Group A patients on initial separation from CPB (P< 0.05). Of the 10 patients in Group B, five required phenylepherine to maintain the mean arterial pressure (MAP) >65 mmHg, whereas none of the Group A patients required phenylephrine for MAP regulation (P< 0.05). We conclude that Infusion of low-dose vasopressin for patients with mild to moderate left ventricular systolic dysfunction during separation from CPB is beneficial for the postoperative hemodynamic profile, reduces the catecholamine doses required and improves left ventricular systolic function.

Is lidocaine patch as effective as intravenous lidocaine in pain and illus reduction after laparoscopic colorectal surgery? A randomized clinical trial.

OBJECTIVE: To evaluate the efficacy of lidocaine patch applied around wound in laparoscopic colorectal surgery in reduction of postoperative pain and illus compared to intravenous lidocaine infusion and placebo. BACKGROUND: Postoperative illus and pain after colorectal surgery is a challenging problem associated with increased morbidity and cost. Inflammatory response to surgery plays crucial rule in inducing postoperative illus. Systemic local anesthetics proved to have anti-inflammatory properties that may be beneficial in preventing ileus added to its analgesic actions. The lidocaine patch evaluated in many types of pain with promising results. We try to evaluate the patch in perioperative field as a more simple and safe technique than the intravenous route. MATERIALS AND METHODS: Prospective, randomized, controlled study was conducted, comparing three groups. Group 1 (placebo) received saline infusion, group 2 received i.v. lidocaine infusion after induction of anesthesia, 2 mg/min if body weight >70 kg or 1 mg/min if body weight <70 kg, group 3 received lidocaine patch 5%, three patches each one divided into two equal parts and applied around the three wounds just before induction. Data collected were, pain scores (VAS), morphine consumption, return of bowel function, pro-inflammatory cytokines plasma levels and plasma lidocaine level. RESULTS: Pain intensity (VAS) scores at rest and during coughing were significantly lower during the first 72 h postoperative in i.v. lidocaine group and patch group compared to the placebo group. Mean morphine consumption were significantly lower in the i.v. lidocaine group and patch group compared to placebo group. Return of the bowel function was significantly earlier in i.v. lidocaine group in comparison to the other groups. Proinflammatory cytokines (IL6, IL8, and C3a) were significantly lower in i.v. lidocaine group compared to the other two groups. CONCLUSION: The lidocaine patch was equal to i.v. lidocaine infusion in decreasing pain scores and morphine consumption but not in acceleration of bowel function return.

Patient-ventilator asynchrony during daily interruption of sedation versus no sedation protocol.

INTRODUCTION: Daily interruption of sedation could minimize the problem of sedatives accumulation. Nevertheless, whatever is the sedation strategy; sedation, particularly deep levels, has been associated with high frequency of patient-ventilator asynchrony. Extending these findings, one would expect that no sedation protocol could reduce the frequency of patient-ventilator asynchrony. AIM: To assess the effect of no sedation protocol compared with daily interruption of sedation on patient-ventilator asynchrony in surgical intensive care patients. MATERIALS AND METHODS: The study included 230 patients who expected to require mechanical ventilation for more than 48 h. They were randomized to receive either continuous sedation (1 mg/mL midazolam) to achieve a Ramsay score of 3-4 with daily interruption until awake (group D; n = 115), or no sedation (group N; n = 115). Both groups received bolus doses of morphine (2.5-5 mg) as needed to achieve a score of ≤2 on behavioral pain scale. RESULTS: No sedation was associated with significantly lower ineffective triggering and asynchrony index but significantly higher double triggering. Patient's effort during triggering was significantly higher during no sedation. The respiratory rate increased and the PaCO2 decreased significantly in no sedation group. CONCLUSION: No sedation protocol reduces the asynchrony index and preserves the patient's effort during triggering.