Comparative induction of controlled circulation by magnesium and remifentanil in spine surgery

Comparison of the effects of tranexamic acid, nitroglycerin, and remifentanil on the prevention of bleeding during herniated lumbar intervertebral disc surgery: A randomized clinical trial

Background

Surgery is a well-known and effective method of treating lumbar intervertebral disc herniation. The present study aimed to compare the effects of administering tranexamic acid (TXA), nitroglycerin (NTG), and remifentanil (REF) on hemorrhage prevention during herniated lumbar intervertebral disc surgery.

Methods

A double-blind clinical trial was conducted on 135 participants undergoing lumbar intervertebral disc surgery. A randomized block design was used for subject assignment to three groups including TXA, NTG, and REF. The hemodynamic parameters, bleeding rate, hemoglobin level, and the amount of infused propofol were measured and recorded after surgery. Data were then analyzed in SPSS software using Chi-square test and analysis of variance.

Results

The mean age of participants in the study was 42.12 ± 7.93 years, and all three groups were equal in terms of demographic characteristics (P > 0.05). The mean arterial pressure (MAP) of the TXA and NTG groups was notably higher than the REF group (P < 0.008). The mean heart rate (HR) of the TXA and NTG groups was notably higher than the REF group (P < 0.05). The propofol dosage used in the TXA group was higher than the two groups of NTG and REF (P < 0.001).

Conclusion

Among participants undergoing lumbar intervertebral disc surgery, the greatest MAP variability was observed in the NTG group. Higher mean HR and propofol consumption was observed in the NTG and TXA groups when compared to REF. No statistically significant differences were noted between groups in oxygen saturation or bleeding risk. Based on these findings, REF may be considered a preferred surgical adjunct over TXA and NTG during lumbar intervertebral disc surgery.

Comparative study of the effect of two different doses of remifentanil on bleeding control in lumbar fusion surgery: A randomized clinical trial

Objectives

Spinal fusion surgery completely prevents movement or friction between the two vertebrae. Remifentanil, a selective drug agonist, suppresses and decreases the vasomotor system upon release of histamine. In this study, the efficacy of remifentanil infusion at doses of 0.1 and 0.3 μg/kg/min in the control of low blood pressure was compared.

Methods

In this randomized clinical trial, 110 candidates for selective spinal fusion surgery were entered and randomized into 2 groups. The first group received 0.1 μg/kg/min and in the second group 0.3 μg/kg/min remifentanil. The systolic and diastolic blood pressure, pulse rate, SPO2, and surgeon's satisfaction were measured and compared between groups.

Results

the systolic blood pressure was significantly lower in patients receiving 0.3 μg of remifentanil by the time 30, 45, 60, and 90 min during the surgeries (P < 0.05). No significant difference was observed in terms of PR (P = 0.19) and SPO2 (P = 0.41) between the two groups. We also observed significantly higher duration of surgeries (P = 0.002), duration of anesthesia (P = 0.009), significantly higher bleeding volume (P < 0.001), higher fluid intake (P = 0.01) and higher transfused blood (P = 0.01) in patients that received 0.1 μg remifentanil compared to other patients.

Conclusion

Here we showed that administration of 0.3 μg/kg/min remifentanil was associated with significantly lower systolic blood pressure during the surgeries. On the other hand, patients that received 0.1 μg/kg/min remifentanil had significantly higher duration of surgeries, duration of anesthesia, significantly higher bleeding volume, higher fluid intake, and also higher transfused blood.

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Spinal fusion surgery completely prevents movement or friction between the two vertebrae.

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Remifentanil, a selective drug agonist, suppresses and decreases the vasomotor system.

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0.3 μg/kg/min remifentanil was associated with significantly lower systolic blood pressure.

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Patients that received 0.1 μg/kg/min remifentanil had significantly higher duration of surgeries.

Effects of Magnesium Sulfate on Intraoperative Blood Loss and Anesthetic Requirement in Meningioma Patients Undergoing Craniotomy with Tumor Removal: A Prospective Randomized Study

Background Meningioma brain tumor is associated with significant blood loss. Magnesium (Mg), a calcium blocker, can facilitate blood pressure control during surgery. This study aimed to evaluate effects of magnesium on blood loss, anesthetic requirement, and its neuroprotective effect in meningioma patients undergoing craniotomy.

Methods Eighty patients aged between 18 and 70, American Society of Anesthesiologists physical status I and II, diagnosed with meningioma and scheduled for craniotomy tumor removal were randomized into two groups. Group M (Mg) received intravenous magnesium sulfate 40 mg/kg over 30 minutes initiated at skin incision and followed by continuous infusion of 10 mg/kg/h until dura closure. Group N (NSS) received 0.9% NaCl as placebo. Anesthesiologists in charge, surgeons, and patients were all blinded. The assessed outcomes were perioperative blood loss, anesthetic requirement, and pre- and postoperative neurocognitive functions assessed by Montreal Cognitive Assessment (MoCA).

Results Thirty-eight patients in each group were analyzed. In group M, the intraoperative blood losses were 500 (70, 2300) mL, and 510 (100, 1600) mL in group N (p = 0.315). Patients who received blood within 24 hours were 39.5% in group M and 47.4% in group N (p = 0.644). No differences were observed in anesthetic requirement, intraoperative mean arterial pressure, hypotensive episodes, and vasopressor usages. There were no significant differences in postoperative MoCA score. Magnesium levels did not exceed acceptable levels.

Conclusions Magnesium administration in meningioma patients had no significant effects on blood loss, anesthetic requirement, and postoperative cognitive function.

Acute hypervolemic hemodilution combined with controlled hypotension to minimize blood loss during operations of spine fusion: remifentanil versus magnesium sulfate

Background

Blood loss is one of the major problems during operations of spine fusion. Several blood-conservative measures were applied to reduce the incidence of blood loss—among them, acute hypervolemic hemodilution (AHH) and controlled hypotension (CH). This study was designed to detect the effect of combination of AHH with CH induced by remifentanil versus magnesium sulfate on the volume of blood loss, allogeneic blood transfusion, hemodynamics, coagulation, and electrolytes during operations for spine fusion which are risky operations with high incidence of blood loss and blood transfusion. Sixty patients scheduled for posterior fusion of the spine were randomly allocated into three groups of 20 patients each (group I (AHH), group II (AHH combined with remifentanil-based CH), and group III (AHH combined with magnesium sulfate-based CH)). Estimated blood loss and total volume of packed red blood cells (PRBCS) transfused were recorded. Arterial blood pressure (ABP) and heart rate (HR) measures were recorded. Blood samples were obtained for the detection of hemoglobin (Hb) and hematocrit (HCT).

Results

Estimated blood loss, percentage blood loss, and intraoperative RBC transfusion units were significantly high in group I in relation to group II and group III (Table 2). Cardiac output was significantly higher in group I in relation to group II and group III at 10, 15, 30, 45, and 60 min after start of AHH. MBP and HR results were significantly high in group I in comparison with group II and group III at 30, 45, 60, and 90 min and 2 and 3 h after start of study drugs. CVP results were significantly high in group I in relation to group II and group III at 15, 30, 45, 60, and 90 min after start of AHH. PTT was significantly increased in the three study groups in comparison with baseline inside each group after AHH.

Conclusion

Combination of AHH with CH induced by remifentanil or magnesium sulfate was associated with reduction in estimated blood loss, and total volume of PRBCS transfused. There was no significant difference between hemodynamic parameters with the use of remifentanil or magnesium sulfate except that SBP, DBP, and MBP results were significantly high with magnesium sulfate at 15 min after drug infusion. There was significant increase in PT and PTT after AHH that was not reflected by significant blood oozing from the operative field, or by difficulty in hemostasis.

Perioperative Care of Patients Undergoing Major Complex Spinal Instrumentation Surgery: Clinical Practice Guidelines From the Society for Neuroscience in Anesthesiology and Critical Care

Evidence-based standardization of the perioperative management of patients undergoing complex spine surgery can improve outcomes such as enhanced patient satisfaction, reduced intensive care and hospital length of stay, and reduced costs. The Society for Neuroscience in Anesthesiology and Critical Care (SNACC) tasked an expert group to review existing evidence and generate recommendations for the perioperative management of patients undergoing complex spine surgery, defined as surgery on 2 or more thoracic and/or lumbar spine levels. Institutional clinical management protocols can be constructed based on the elements included in these clinical practice guidelines, and the evidence presented.

Effects of controlled hypotension with restrictive transfusion on intraoperative blood loss and systemic oxygen metabolism in elderly patients who underwent lumbar fusion

BACKGROUND

The effects of restrictive fluid therapy combined with controlled hypotension in the elderly on systemic oxygen metabolism and renal function are clinical concerns. The aim of this study was to evaluate blood loss, oxygen metabolism, and renal function in different levels of controlled hypotension induced by intravenous nitroglycerin, in combination with limited infusion, in elderly patients undergoing posterior lumbar fusion.

METHODS

A total of 40 patients, aged 60-75 with ASA grade II or III, who were planned for posterior lumbar fusion were randomly allocated into two groups: experimental group [target mean arterial pressure 65 mmHg (MAP 65) or control group (MAP 75)]. Indicators for blood loss, hemodynamic, systemic oxygen metabolism, and renal function evaluation index were recorded before operation (T0), 1 h after induced hypotension (T1), 2 h after hypotension (T2), and in recovery (T3). We compared changes in these parameters between groups to evaluate the combined effects of controlled hypotension with restrictive infusion.

RESULTS

CI, DO₂I, and VO₂I were lower in both groups at T1-T3 compared with T0 (p < 0.05). DO₂I and VO₂I in the MAP 65 group were lower than the MAP 75 group after operation. In both groups, SCysC increased at T1, T2, and T3 (p < 0.05) compared with T0.

CONCLUSIONS

Restrictive transfusion and control MAP at 65 mmHg can slightly change in renal function and reduce the risk of insufficient oxygen supply and importantly have no significant effect on blood loss and postoperative complications.

TRIAL REGISTRATION

ChiCTR-INR-16008153 . Registered on 25 March 2016.

Perioperative concerns in Pott's spine: A review

Pott's disease is the most common granulomatous spine infection caused by tubercle bacilli and is a common site of osseous tuberculosis, accounting for 50–60% of cases. The delay in establishing diagnosis and management results in complications such as spinal cord compression and spinal deformity. The aim of this narrative review is to discuss the perioperative concerns in patients for spine surgery. The literature source for this review was obtained via PubMed, Medline, Google Scholar, Cochrane database of systematic reviews, and textbooks until December 2019. On the literature search, we could not retrieve any review article specifically discussing the perioperative concerns of spinal tuberculosis. Therefore, the aim of the present narrative review is to discuss the perioperative concerns of patients for spine surgery along with the specific concerns related to spinal tuberculosis.

Effects of perioperative magnesium sulfate with controlled hypotension on intraoperative bleeding and postoperative ecchymosis and edema in open rhinoplasty

PURPOSE

This randomized, double-blind study was planned to evaluate the effect of perioperative magnesium sulfate with controlled hypotension on intraoperative bleeding, postoperative ecchymosis and edema, and side-effects.

MATERIALS AND METHOD

Forty-nine patients undergoing open rhinoplasty were divided into two groups - magnesium sulfate and control. The magnesium sulfate group received 30-50 mg·kg^-1 intravenously as a bolus before induction of anesthesia, followed by 10-20 mg·kg^-1 h^-1 by continuous intravenous infusion during surgery. Anesthesia was induced with propofol 3 mg·kg^-1, fentanyl 15 μg·kg^-1 and cisatracurium 0.6 mg·kg^-1. Mean arterial pressure was maintained at 50 to 60 mmHg under controlled hypotensive anesthesia with magnesium sulfate titration. Hemodynamic variables, operational bleeding, early postoperative side-effects and postoperative first-, third- and seventh-day ecchymosis and edema were compared between the groups. Ecchymosis and edema were evaluated using a graded scale from 0 to 4.

RESULTS

In the magnesium sulfate group, mean arterial pressure decreased during most of the perioperative period. Intraoperative bleeding also decreased. A distinct reduction in ecchymosis and edema was observed in both the upper and lower eyelids on the first, third and seventh days. Patients in the magnesium sulfate group also had a more peaceful postoperative course with less postoperative nausea vomiting, and shivering.

CONCLUSION

Magnesium sulfate with controlled hypotension can lower ecchymosis and edema of the upper and lower eyelids in rhinoplasty surgery by reducing bleeding.

Effects of perioperative magnesium sulfate infusion on intraoperative blood loss and postoperative analgesia in patients undergoing posterior lumbar spinal fusion surgery: A randomized controlled trial

OBJECTIVE

Many studies have suggested the anti-nociceptive role for magnesium either as an adjunct for postoperative pain. Although several studies have been carried out to evaluate the anti-nociceptive effect of magnesium, there is still considerable uncertainty.

PATIENTS AND METHODS

Eighty patients who underwent posterior spinal fusion were randomly divided into two groups (magnesium and saline). Changes in cell count, magnesium concentration and coagulation status were assessed one hour after operation at both group and compared to baseline. At recovery room, their pain score was assessed according to 10 points visual analogue scale (VAS). Morphine consumption was evaluated at regular times after the surgery by patient controlled analgesia (PCA) device.

RESULTS

VAS scores were significantly lower in the magnesium group. Cumulative PCA morphine consumption after the surgery was significantly lower in the magnesium group. Pre and postoperative values for haemoglobin, platelet count, Prothrombin Time (PT), fibrinogen were not significantly different. There was a significant increase in activated Partial Thromboplastin Time (aPTT), International Normalized Ratio (INR), and bleeding time (BT), one hour after the operation in the magnesium group but intraoperative blood loss was similar in both groups.

CONCLUSIONS

Perioperative magnesium sulfate infusion improves the postoperative analgesia, decreases the amount of morphine consumption after the operation and does not change the intraoperative bleeding in patients undergoing posterior spinal fusion surgery.

Controlled hypotension for FESS: A randomised double-blinded comparison of magnesium sulphate and dexmedetomidine

Background and Aims:

Intense bleeding during general anaesthesia (GA) is the major limitation during functional endoscopic sinus surgery (FESS). This study was aimed to compare the efficacy of dexmedetomidine and magnesium sulphate (MgSO₄) for controlled hypotension in FESS.

Methods:

Sixty eight patients undergoing FESS were randomised to receive either dexmedetomidine 1 μg/kg over 10 min followed by infusion at 0.2 to 0.7 μg/kg/h (Group D) or MgSO₄ 40 mg/kg over 10 min followed by an infusion at 10 to 15 mg/kg/h (Group M). Anaesthesia and infusion rates for study drugs were maintained with sevoflurane to keep MAP between 60–70 mmHg throughout the surgery. The time to reach the target MAP, the number of patients requiring a minimum and maximum infusion doses of study drugs were noted.

Results:

The mean time to achieve target mean arterial pressure (MAP) was less in group D (10.59 ± 2.04) as compared with (21.32 ± 4.65 min) group M (P < 0.001). The target MAP was achieved between 5–15 min in 73.52% patients (Group D) with an infusion dose of 0.2–0.4 μg/kg/h of dexmedetomidine without the use of sevoflurane, while 82.35% patients in group M required 4% sevoflurane along with >12–15 mg/kg/hr infusion of MgSO₄ to achieve target MAP in 10–20 min.

Conclusion:

Dexmedetomidine is superior to MgSO₄ in achieving target MAP in lesser time with minimum infusion dose.

Remifentanil inhibits the traumatic stress response in emergent trauma surgery

OBJECTIVE

The aim of this study was to explore whether remifentanil could inhibit the stress response in emergent trauma surgery more effectively than sufentanil.

PATIENTS AND METHODS

Sixty trauma patients for emergent surgery were randomly divided into remifentanil group (R group, n = 30) or sufentanil group (S group, n = 30). The patients in the R group were continuously intravenously infused with remifentanil, while those in the S group were administrated with sufentanil. The plasma contents of cortisol (COR), epinephrine (E), norepinephrine (NE), and blood glucose were measured before anesthesia induction (T1), 5 minutes after intratracheal intubation (T2) and 5 minutes (T3), 30 minutes (T4), and 1 hour (T5) after surgery, respectively. The blood pressure (BP) and the heart rate (HR) at these time points were recorded as well.

RESULTS

The results showed that the patients in the R group had more stable hemodynamics during the surgery and had a significantly lower HR at T2-T5 than those in the S group. The plasma levels of norepinephrine at time points T3-T5 and levels of cortisol at T4-T5 in the R group were significantly lower than those in the S group (P < 0.05).

CONCLUSIONS

The results in the present study indicated that remifentanil could inhibit the stress response in emergent trauma surgery patients more effectively than sufentanil.

Controlled Hypotension During Rhinoplasty: A Comparison of Dexmedetomidine with Magnesium Sulfate

Objective

The current study aimed at comparing the efficacy of dexmedetomidine and magnesium sulfate to control blood pressure (BP) during rhinoplasty and the resultant effects on the quality of surgical field in terms of bleeding and visibility.

Methods

The current randomized, prospective, double-blind study was conducted on 60 patients aged 18 to 50 years classified as ASA (American Society of Anesthesiologists) physical status I who were candidates for rhinoplasty. Patients were randomly divided into 2 groups: (1) group Dex, received 1 µg/kg dexmedetomidine in 10 minutes before induction of anesthesia, followed by 0.4 - 0.6 µg/kg/hour during the maintenance of anesthesia, and (2) group Mg, received 40 mg/kg in 10 minutes before anesthesia induction followed by 10 - 15 mg/kg/hour during anesthesia maintenance. In both groups, the goal was to achieve a mean arterial pressure (MAP) of 60 - 70 mmHg. Hemodynamic variables, anesthetic, opioid, muscle relaxant requirements, and surgical field condition were recorded. Sedation score, time to reach modified Aldrete score ≥ 9, and adverse effects including nausea and vomiting (N&V) and shivering were recorded.

Results

Controlled hypotension was achieved in both groups. There was no significant difference in MAP between the groups, but heart rate (HR) was significantly lower in the Dex group (P < 0.001), compared with that of the Mg group. Bleeding score was lower (P < 0.001) and surgeon's satisfaction score was higher (P < 0.001) in the Dex group. More patients required fentanyl (P < 0.001) or nitroglycerin (P < 0.001) and the mean fentanyl (P = 0.005) or nitroglycerin (P < 0.001) required doses were higher in the Mg group. Patients in the Dex group required more frequent administration of cisatracurium (P = 0.004). Five patients in the Dex group versus no patients in the Mg group received atropine (P = 0.023). Ramsay sedation score and time to reach modified Aldrete score ≥ 9 were significantly higher in the Dex group (P < 0.001 and P < 0.001, respectively). The incidence rate of N&V and shivering were similar in both groups.

Conclusion

Dexmedetomidine was more effective than magnesium to achieve controlled hypotension, and provide a favorable surgical field condition. However, dexmedetomidine also heightened the risk of induced bradycardia and prolonged sedation. These are 2 important points to consider when applying this drug as a hypotensive agent during operation.

Comparison of quality of the surgical field after controlled hypotension using esmolol and magnesium sulfate during endoscopic sinus surgery

Background and Aims:

Most vital aspect of Endoscopic Sinus Surgery (ESS) is an optimal visibility in the surgical field. This invariably requires controlled hypotension to facilitate surgical dissection and to decrease operative time. We used esmolol and magnesium sulfate to achieve controlled hypotension and assessed the quality of the surgical field in ESS.

Material and Methods:

A total of 30 patients undergoing ESS, were enrolled in three parallel groups of 10 patients each in a prospective randomized double-blind study. “Magnesium Sulfate group” received magnesium sulfate 40 mg/kg intravenously (i.v.) as a bolus over 10 min before induction of anesthesia, followed by 15-30 mg/kg/h through infusion. “Esmolol group” received 0.5 mg/kg i.v. bolus over 10 min after induction followed by 150-300 μg/kg/min infusion and “control group” received normal saline in same volume schedule. The primary aim was to assess the quality of surgical field, using Fromme scale. Category Scale values of all the three groups were compared using Kruskal-Wallis analysis of variance (ANOVA) test. Hemodynamic data was compared using ANOVA test.

Results:

Quality of the surgical field was better in both magnesium sulfate and esmolol groups as compared to the control group. Durations of anesthesia and surgery were significantly lower in esmolol group as compared to the control group. Blood loss was comparable in all the three groups.

Conclusion:

Quality of the surgical field was better in esmolol and magnesium sulfate groups as compared to control group. Duration of surgery was significantly less in esmolol group as compared to other two groups.

Remifentanil infusion during emergence moderates hemodynamic and cough responses to the tracheal tube: A randomized controlled trial

OBJECTIVE

To examine the severity of cough and straining at the time of emergence from anesthesia.

DESIGN

Double-blind randomized, placebo-controlled study.

SETTING

University-affiliated hospital.

PATIENTS

Sixty-two American Society of Anesthesiologists 2 patients undergoing craniotomy and excision of supratentorial cerebral tumors.

INTERVENTION

Intravenous infusion of remifentanil (REM) at 0.05 μg/kg/min or normal saline (NS) upon termination of the surgical procedure.

MEASUREMENTS

Heart rate (HR) and mean arterial pressure (MAP) along with the frequency and severity of cough response (Modified Minogue Scale) to the endotracheal tube were recorded at different time points. The frequency of cough and straining was analyzed with χ(2) tests. HRs and MAP were analyzed by repeated-measures analysis of variance between REM and NS groups.

MAIN RESULTS

There was no case of significant cough in the REM group, and all of the patients in the NS group developed some extent of cough varying from mild retching to severe coughing episodes (P < .001). Both the HR and MAPs were consistently lower in the REM group compared to the NS group.

CONCLUSION

Infusion of REM at the end of craniotomy procedures results in significant reduction of the frequency and severity of coughing and straining. Compared to placebo, REM moderates increases in MAP upon emergence from general anesthesia until the time of extubation.