Comparison of Controlled Hypotension Due to the Use of Dexmedetomidine, Magnesium Sulfate, and Esmolol in Craniotomy Surgery

Introduction: Craniotomy includes the temporary removal of bone flap from calvarium to access the intracranial contents, which is usually used to reduce intracranial pressure. Induced or controlled hypotension is a method by which arterial blood pressure is predictably reduced, thus reducing bleeding. Therefore, the present study aimed to compare the dexmedetomidine, magnesium sulfate, and esmolol in controlled hypotension in craniotomy of patients with brain injury. Materials and methods: In this randomized double-blind clinical trial, 45 patients entered into study based on inclusion criteria. All patients were monitored when entering operating room. The questionnaire was completed by all groups, in which PR, MAP (Mean Arterial Pressure), mean bleeding score, mean of received packed cells, controlled hypotension and bradycardia, and survival of patients were recorded. Data were analyzed using spss software version 19, and ANOVA and T-Test were used for statistical significance analysis. Results: The mean age and standard deviations of the three groups of dexmedetomidine, esmolol and magnesium sulfate were 36.78±10.32, 34.47±10.58, and 39.67±11.99 years, respectively. There was no significant difference between the three groups in terms of age, gender, initial heart rate and baseline blood pressure (BP). The MAP and bleeding score (P=0.04 and P=0.0001) was significantly lower in the dexmedetomidine group than in the other two groups. Although the heart rate in the esmolol group was lower than the other two groups, the difference was not significant (P = 0.128). Unlike esmolol and magnesium sulfate groups, GOS did not decrease in the dexmedetomidine group. Conclusion: Comparison of the three groups in controlled hypotension in craniotomy surgery showed that the MAP and bleeding score of dexmedetomidine group was significantly lower than the other two groups, and the GOS didn’t decrease in this group. In general, dexmedetomidine would be a better choice for controlled hypotension in craniotomy.

Controlled Hypotension Combined with Femoral Nerve Block for Knee Replacement without Tourniquet

In the process of knee replacement surgery, the use of tourniquet technology for hemostasis is the most common method. But the adverse reactions of tourniquets in knee replacement surgery have become more prominent in recent years. More and more scholars have begun to advocate the optimization of the use of tourniquet technology, thereby controlling the use of tourniquet technology. In this study, 125 patient cases were randomly divided into four experimental groups for comparative analysis. The two sets of variables are whether to use tourniquet during surgery and use intravenous analgesia or nerve block analgesia. Studies have shown that when using a tourniquet for knee replacement surgery, the chance of hidden blood loss increases after use. The tourniquet was not used during the operation, the patient's thighs were swollen, and postoperative pain was reduced. Compared with intravenous analgesia, knee joint replacement with uncontrolled tourniquet combined with femoral nerve block has a better analgesic effect and can effectively relieve pain after knee replacement. Therefore, under the method of controlled hypotension combined with femoral nerve block, TKA surgery without using tourniquet technology is more conducive to early health recovery and pain relief after TKA surgery, as well as functional exercise and knee joint recovery during postoperative recovery.

Comparative Study between Nitroglycerine, Magnesium Sulfate and Dexmedetomidine to Induce Hypotension During Functional Endoscopic Sinus Surgery (FESS)

Background Functional Endoscopic Sinus Surgery (FESS) has been employed as a surgical intervention to treat chronic rhinosinusitis in patients with no response to drug therapy, during which the surgical vision may be greatly reduced by a small amount of bleeding. There by, the intraoperative controlled hypotension can improve the visibility. While excessive bleeding intraoperative cause serious complications in the postoperative period, including eye socket infections, visual acuity damage, meningeal infections, and other. Objective Induced hypotension limits intra operative (IO) blood loss provides better visibility of the surgical field and diminishes the incidence of major complications during Functional Endoscopic Sinus Surgery (FESS). We aimed at comparing Nitroglycerine; Magnesium Sulfate and Dexmedetomidine for inducing controlled hypotension and evaluate narcotic used, mac of inhalational anesthesia, and Ramsay Sedation Scale (RSS) in the recovery and pre-anesthetic time in patients undergoing Functional Endoscopic Sinus Surgery (FESS). Patients and Methods This study was conducted on 75 patients who underwent elective functional endoscopic sinus surgery (FESS) who matched the inclusion criteria and were randomly allocated into 3 groups each containing 25 patients. The first group received loading dose of dexmedetomidine 1μg/kg infused over 10 min before induction of anesthesia then 0.7 μg/kg/h via syringe pump, second group received nitroglycerine infusion at a dose of 2μg/kg/min according to the response started after induction, intubation, positioning and sterilization of the patient and third group received a loading dose of magnesium sulfate 40 mg/kg over 10 minutes followed by an infusion 15mg/kg/h via syringe pump. Results The result of our study showed that dexmedetomidine, magnesium sulfate, or nitroglycerine successfully induced deliberate hypotension and were effective in providing good surgical field during FESS, but dexmedetomidine showed superior hemodynamic profile. Compared with nitroglycerine, both dexmedetomidine and magnesium sulfate offered the advantage of inherent analgesic and sedative effect. Conclusion Dexmedetomidine, magnesium sulfate, or nitroglycerine successfully induced deliberate hypotension and were effective in providing good surgical field during FESS, but dexmedetomidine showed superior hemodynamic profile. Compared with nitroglycerine, both dexmedetomidine and magnesium sulfate offered the advantage of inherent analgesic and sedative effect. Dexmedetomidine also showed shorter duration of surgery with less blood loss and favorable frommer score with more surgeon satisfaction. Dexmedetomidine showed longest time to 1st analgesic rescue in PACU comparing with magnesium sulfate and nitroglycerine. So, it’s advised to use dexmedetomidine to induce hypotension than magnesium sulfate and nitroglycerine. However, dexmedetomidine should be used with caution as it caused hypotension and bradycardia, t had sedative effect with low aldert score comparing with nitroglycerine and magnesium sulfate.

Effect of Different Loading Doses of Dexmedetomidine on Controlled Hypotension and the Incidence of Bradycardia During Rhinoplasty: A Clinical Trial

: Controlled hypotension, with a mean arterial pressure (MAP) of 60 mmHg - 70 mmHg, provides a bloodless and visible surgical field during rhinoplasty. It has been shown that dexmedetomidine, an α2-adrenoreceptor agonist, is a suitable choice in this regard. One of the disadvantages of this drug is the possibility of severe bradycardia during infusion. Therefore, we compared lower intravenous (IV) loading doses to determine whether the hypotensive effect of the drug was preserved and the bradycardia incidence decreased. In this randomized, double-blinded clinical trial, 81 patients aged 18 to 50 years with the American Society of Anesthesiologists physical status (ASA-PS) class I and II, scheduled for rhinoplasty randomly received 1.0, 0.9, and 0.8 µg/kg (named as groups 1.0, 0.9, and 0.8, respectively) of IV dexmedetomidine before the induction of anesthesia followed by infusion (0.3 - 0.7 µg/kg/h) during operation. The patients’ heart rate (HR), MAP, the requirements for nitroglycerin (NTG) and extra fentanyl, as well as the incidence of bradycardia, were recorded. Bleeding and visibility of the surgical field were scored by the surgeon using a 6-point visual scale. MAPs, HRs, and consumption of NTG and extra fentanyl were similar in the studied groups. The surgical field was more visible and bloodless in group 1.0 compared to group 0.8 (P < 0.001); the differences were not significant between groups 1.0 and 0.9 (P = 0.605). The incidence (P = 0.027) and the severity of bradycardia (P = 0.017) were higher in the groups with higher loading doses. We concluded that dexmedetomidine is an acceptable agent to provide controlled hypotension. A loading dose of 0.9 µg/kg, but not 0.8 µg/kg, provides similar surgical field conditions as the dose of 1 µg/kg. Furthermore, despite the decrease in the incidence of bradycardia, the hypotensive effect of the drug is preserved.

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.

Prospective randomised control study of dexmedetomidine for controlled hypotension in functional endoscopic sinus surgery

<p class="abstract"><strong>Background: </strong>Functional endoscopic sinus surgery is one of the commonly performed Surgeries. Induced hypotension is a method employed in functional endoscopic sinus surgery to reduce blood loss and to improve the visibility of the surgical field. This study aimed to evaluate the effect of dexmedetomidine infusion on the requirement of Isoflurane to produce controlled hypotension (mean arterial pressure of 60-70 mmHg), quality of the bloodless surgical field, duration of surgery, and the awakening time in patients undergoing Functional endoscopic sinus surgery (FESS).</p><p class="abstract"><strong>Methods: </strong>50 patients were divided into Group D, Group C Group D. After successful tracheal intubation, anesthesia was maintained with 66% nitrous oxide + 33% oxygen + isoflurane titrated to achieve a mean arterial pressure (MAP) of 60-70 mmHg. Isoflurane and dexmedetomidine/saline infusion was stopped 10-15 minutes before the end of surgery. The intraoperative surgical field was assessed by using a 6 points Fromme-Boezaart scale.</p><p class="abstract"><strong>Results:</strong> A statistically significant (p&lt;0.001) reduction in intraoperative isoflurane requirement in patients receiving dexmedetomidine infusion (0.387±0.102) in comparison to those receiving placebo (1.7±0.211). Both the group provided better visualization of the surgical field. The duration of surgery was statistically (p=0.004) low in Group D (76.84±14.174) compared to group C (94.1±25.083). The awakening time in min was statistically (p=0.001) low in group D (5.12±1.691) compared to group C (9.72±1.100).</p><p class="abstract"><strong>Conclusions: </strong>Dexmedetomidine infusion helps in achieving a targeted reduction in MAP reduced intraoperative Isoflurane requirement, better bloodless field, and faster awakening in patients undergoing Functional endoscopic sinus surgery.</p>

Controlled hypotension during neuraxial anesthesia is not associated with increased odds of in-hospital common severe medical complications in patients undergoing elective primary total hip arthroplasty – A retrospective case control study

Introduction The use of controlled hypotension during neuraxial anesthesia for joint arthroplasty is controversial. We conducted a large institutional database analysis to assess common in-hospital complications and mortality of patients undergoing primary total hip arthroplasty (THA) under controlled hypotension and neuraxial anesthesia. Methods We conducted a large retrospective case control study of 11,292 patients who underwent primary THA using neuraxial anesthesia between March 2016 and May 2019 in a single institution devoted to musculoskeletal care. The degree and duration of various mean arterial pressure (MAP) thresholds were analyzed for adjusted odds ratios with composite common severe complications (in-hospital myocardial infarction, stroke, and/or acute kidney injury) as the primary outcome. Results Sixty-eight patients developed common severe complications (0.60%). Patients with complications were older (median age 75.6 vs 64.0 years) and had a higher American Society of Anesthesiologists (ASA) classification (45.6% vs 17.6% ASA III). The duration of hypotension at various MAP thresholds (45 to 70 mm Hg) was not associated with increasing odds of common severe medical complications. Conclusions Controlled hypotension (ranging from 45 to 70 mmHg) for a moderate duration during neuraxial anesthesia was not associated with increased odds of common severe complications (myocardial infarction, stroke, and/or acute kidney injury) among patients receiving neuraxial anesthesia for elective THA.

To Compare the Efficacy of Dexmedetomidine Versus Labetalol in Providing Controlled Hypotension in Functional Endoscopic Sinus Surgery

Background: Functional endoscopic sinus surgery (FESS) is a surgical intervention for sinus diseases. Bleeding is a common concern during FESS. Hemodynamic stability and quality surgical field visibility help to achieve the best outcomes. Objectives: The present study primarily intended to compare the effectiveness of dexmedetomidine versus labetalol in providing controlled hypotension during FESS and then to assess the quality of the surgical field. Methods: The current research was conducted as a prospective randomized double-blinded clinical study. Sixty patients of the American Society of Anesthesiologists grade I or II status undergoing FESS under general anesthesia were divided into two groups, each with 30 members. Patients receiving dexmedetomidine and labetalol were named as group D and L, respectively. The study intended to manage mean arterial pressure (MAP) between 65 - 75 mmHg. The visibility of the operative field was evaluated using Fromme and Boezaart scoring system. Total intraoperative fentanyl consumption and postoperative first analgesic request time were recorded. Results: The MAP target was achieved in both groups. Intergroup differences concerning MAP were observed in both D (75.0 ± 2.0) and L (82.4 ± 5.2) groups (P-value < 0.05). Scores for blood loss were significantly lower in the D group (1.3 ± 0.3) compared to the L group (2.1 ± 0.3) (P-value < 0.05). There was no intergroup difference concerning the mean heart rate (group D; 70.8 ± 4.2, and group L; 73.4 ± 4.4). The total dose of fentanyl consumed was found to be significantly lower in the group D (41.9 ± 5.8) compared to group L (59.9 ± 5.3) (P-value < 0.05). The first analgesic request time was significantly longer in the group D (50.2 ± 9.1) compared to group L (24.8 ± 5.1) (P-value < 0.05). Conclusions: Dexmedetomidine provided better hemodynamic stability and operative field visibility as compared to labetalol during FESS.