Dexmedetomidine and surgical field visibility in nasal surgery: A systematic review and meta-analysis.

INTRODUCTION: Nasal and sinus surgery, especially using endoscopy, relies upon adequate haemostasis to be safe and effective. Often other haemostatic methods, such as cautery are not viable, and other methods must be employed. This study examines the effectiveness of dexmedetomidine in controlled hypotension and for surgical field visibility in endoscopic sinus surgery and other nasal surgeries. REVIEW METHODS: A literature search was conducted in PubMed, Scopus, CINAHL and Central for randomised controlled trials using dexmedetomidine for controlled hypotension in adult patients undergoing endoscopic sinus surgery or other nasal surgery. Meta-analysis of mean differences and single means were performed. RESULTS: Of 935 identified studies, 31 met the inclusion criteria. A statistically significant difference in Fromme-Boezaart surgical field visibility scores was found comparing dexmedetomidine to placebo (p < 0.00001) and propofol (p < 0.0001), but not other agents. A significant difference in intraoperative blood loss volume was found compared with placebo (51.5mL, p < 0.00001) and propofol (13.6mL, p < 0.0001), but not other agents. CONCLUSION: Dexmedetomidine demonstrated significantly improved surgical field visibility and blood loss volume compared with placebo and propofol, but not other agents. Dexmedetomidine is viable and useful for controlled hypotension in nasal surgery. Choice of controlled hypotension agent should follow patient and procedure-specific considerations.

Comparison of labetalol and lidocaine in induction of controlled hypotension in tympanoplasty: a randomized clinical trial.

OBJECTIVES: This study aimed to compare the efficacy of labetalol and lidocaine in tympanoplasty surgery, specifically evaluating their impact on hemodynamic changes and perioperative outcomes. METHODS: A randomized controlled trial was conducted with 64 patients scheduled for tympanoplasty. Patients were randomly assigned to receive either 0.5-2 mg/min labetalol or 1.5 mg/kg/h lidocaine 1% to achieve controlled hypotension during surgery. The efficacy of the drugs was assessed by comparing the Mean Arterial Pressure (MAP), surgeon's satisfaction, time to target MAP, bleeding volume, postoperative pain scores, the need for analgesic medication in recovery, sedation, and other additional parameters. RESULTS: The hemodynamic parameters showed a similar trend over time in both the labetalol and lidocaine groups. The median bleeding volume in the labetalol group (10 cc) was lower than that in the lidocaine group (30 cc), although this difference was not statistically significant (p = 0.11). Similarly, surgeon's satisfaction level, pain intensity, and sedation level in the recovery room did not show statistically significant differences between the two groups (p > 0.05). The duration of surgery, recovery stay, and extubation time also did not significantly differ between the groups. Both medications took approximately the same time (20 min) to reach the target MAP and exhibited comparable hemodynamic responses (p > 0.05). CONCLUSION: Both labetalol and lidocaine effectively achieved controlled hypotension during tympanoplasty surgery, thereby improving surgical conditions. The choice of medication should be based on individual patient characteristics and the anesthesiologist's judgment. LEVEL OF EVIDENCE: II.

Hypotensive Levels on Endoscopic Sinus Surgery Visibility: A Randomized Non-Inferiority Trial.

OBJECTIVE: Optimization of endoscopic sinus surgery (ESS) conditions is a common focus of interest for otolaryngologists and anesthesiologists. Relying on hypotension alone to achieve a bloodless field may not without risks. We sought to determine whether ESS is feasible in the context of moderate hypotension. METHODS: This randomized non-inferiority trial enrolled 96 adult patients who were to undergo ESS. The patients were divided into two groups: Controlled hypotension group (n = 48, MAP reduction to 55-65 mmHg, minimum of 60% of baseline blood pressure) or Individualized hypotension group (n = 48, MAP reduction to 75-80% of baseline blood pressure). All participants were placed in 10° reverse Trendelenburg position during ESS, and cottonoid patties dammed with epinephrine was recommended to clear the operative field of bleeding. The two groups were compared according to Boezaart grading scale (BS) score, estimated blood loss, blood loss rate, arterial lactate level and postoperative recovery. RESULTS: Both levels of intraoperative hypotension (62.2 ± 2.3 mmHg vs. 74.0 ± 2.8 mmHg) provided acceptable surgical conditions with no difference in mean BS scores [2.00 (1.88-2.33) vs. 2.00 (1.85-2.45), p = 0.926]. The 95% CI for median value differences in mean BS scores is lower than the preset non-inferiority margin. There were no differences in blood loss rate and estimated blood loss between two groups (p > 0.05) Postoperative arterial lactate and Ramsay sedation scores were significantly different between the two groups (p < 0.05). CONCLUSIONS: In ESS, both levels of intraoperative hypotension, combined with position adjustment and low-concentration adrenaline to constrict nasal mucosal blood vessels, provided acceptable surgical conditions. LEVEL OF EVIDENCE: 2 Laryngoscope, 134:569-576, 2024.

Effects of smoking on controlled hypotension with nitroglycerin during ear-nose-throat surgery.

Background and Aim: In this study, the aim was to research the effects of smoking habits on controlled hypotension administered with nitroglycerin during ear-nose-throat surgery. Materials and Methods: This study administered controlled hypotension with nitroglycerin and total intravenous anesthesia to a total of 80 patients undergoing septoplasty operations. The patients were divided into two groups of 40 non-smokers (Group 1) and 40 smokers (Group 2). Intravenous propofol infusion was used for anesthesia maintenance. Nitroglycerin with 0.25-1 µg/kg/min dose was titrated to provide controlled hypotension. During this process, the hemodynamic parameters of patients, total propofol and nitroglycerin amounts used, operation duration, and duration of controlled hypotension were recorded at the end of the operation. At the end of the operation, the surgeon assessed the lack of blood in the surgical field with Fromme Scale. Results: Fromme scale values were significantly higher in Group 2 compared to Group 1. The MAP values at 10, 20, 30 min, and end of operation were lower, while 10- and 20-min heart rate values were higher in Group 2 compared to Group 1. Conclusion: Nitroglycerin, chosen for controlled hypotension to reduce hemorrhage in the surgical field during nasal surgery, was shown to cause more pronounced hypotension and reflex tachycardia due to endothelial dysfunction linked to nicotine in patients who smoke. Despite lower pressure values in the smoking group, the negative effects of nicotine on platelet functions combined with similar effects of nitroglycerin to increase bleeding amounts.

A Study of the Effect of Pre-emptive Oral Clonidine on Intraoperative Haemodynamics and Surgical Field Quality During Functional Endoscopic Sinus Surgery Under General Anaesthesia.

Introduction For endoscopic sinus surgery for rhinosinusitis, pre-emptive Alpha 2 agonist clonidine has been used to reduce sympathetic output, which lowers blood pressure and consequently surgical bleeding. The aim of this study was to analyze the effects of oral clonidine premedication in patients undergoing functional endoscopic sinus surgery. Methods This study was performed between December 2020 to November 2022 among two groups of 30 patients each: clonidine (200 µgm oral) and placebo. Parameters were recorded at baseline, 60 mins after administering the drugs, at induction, and at minutes five, 10, 20, 30, 45, 60, 75, 105, and 120. Six-point average category scale for bleeding was studied. IBM SPSS Statistics for Windows, Version 20.0 (Released 2011; IBM Corp., Armonk, New York, United States) was used for statistical analysis, and p < 0.05 was considered significant.  Results Demographic criteria were statistically non-significant. Heart rate (HR) and mean arterial pressure (MAP) were statistically non-significant at baseline and the 120th min mark, and were significant at other time intervals. The blood loss grading was less in the clonidine group, and the difference was found to be statistically significant (P < 0.001). Conclusion Pre-emptive oral clonidine 200 mcg 60 min prior to induction was found to reduce surgical bleeding by controlling haemodynamics.

Dexmedetomidine induced hypotension and hemostatic markers.

Background and Aims: The hemostatic system undergoes extensive alterations following surgical trauma leading to a hypercoagulable state. We assessed and compared the changes in platelet aggregation, coagulation, and fibrinolysis status during normotensive and dexmedetomidine-induced hypotensive anesthesia in patients undergoing spine surgery. Material and Methods: Sixty patients undergoing spine surgery were randomly allocated into two groups: normotensive and dexmedetomidine-induced hypotensive groups. Platelet aggregation was assessed preoperatively, 15 min after induction, 60 min, and 120 min after skin incision, at the end of surgery, 2 h and 24 h postoperatively. Prothrombin time (PT), activated partial thromboplastin time (aPTT), platelet count, antithrombin III, fibrinogen, and D-dimer levels were measured preoperatively, 2 h and 24 h postoperatively. Results: Preoperative platelet aggregation (%) was comparable between both groups. Platelet aggregation significantly increased intraoperative at 120 min after skin incision and postoperatively in the normotensive group compared to the preoperative value (P < 0.05) but it was insignificantly decreased during the intraoperative induced hypotensive period in the dexmedetomidine-induced hypotensive group (P > 0.05). Postoperative PT, aPTT significantly increased and platelet count, and antithrombin III significantly decreased in the normotensive group compared to the preoperative value (P < 0.05) but they were not significantly changed in the hypotensive group (P > 0.05). Postoperative D-dimer significantly increased in the two groups compared to the preoperative value (P < 0.05). Conclusion: Intraoperative and postoperative platelet aggregation significantly increased in the normotensive group with significant alterations of the coagulation markers. Dexmedetomidine-induced hypotensive anesthesia prevented the increased platelet aggregation that occurred in the normotensive group with better preservation of platelet and coagulation factors.

Does preoperative administration of hypotensive agents affect the quality of the surgical field during endoscopic sinus surgery? A triple-blind randomized controlled trial.

PURPOSE: Endoscopic sinus surgery (ESS) is a surgical procedure widely used in the treatment of various sinonasal conditions. Excessive bleeding during ESS leads to potentially major complications. The primary aim of this trial was to explore any different effects of bisoprolol and nifedipine on the intraoperative surgical field. In addition, the correlations regarding surgical field state, total blood loss (TBL), mean arterial pressure (MAP), and heart rate (HR) were also examined. METHODS: A prospective, triple-blinded, randomized, placebo-controlled trial was conducted, including 72 patients between 18 and 65 years of age who underwent ESS. As an indicator of the worst state of the intraoperative surgical field, the Boezaart scale score was used, as evaluated by two surgeons. Appropriate statistical analysis was conducted to explore score comparisons across groups and correlations between vital signs, bleeding, and the operative field state. RESULTS: No statistically significant difference was found among different intervention groups regarding the worst state of the surgical field (p = 0.367 > 0.05). The Boezaart scale score was positively correlated with TBL (rxy = 0.619, p = 0.000 < 0.001) and MAP (rxy = 0.259, p = 0.028 < 0.05). Furthermore, MAP was positively correlated with HR (rs = 0.254, p = 0.32 < 0.05). CONCLUSION: Our study demonstrates that preoperative administration of bisoprolol and nifedipine does not affect the worst state of the operative field. However, vital signs seem to either directly or indirectly affect bleeding and operative field state, and agents affecting them are worth exploring further.

Use of dexmedetomidine for controlled hypotension in middle ear surgery: A systematic review and meta-analysis.

BACKGROUND: Microsurgical operations such as middle ear surgery rely heavily on visibility of the surgical field. Anesthetic techniques such as controlled hypotension have been developed to improve surgical field visibility by attempting to decrease bleeding. Many agents have been utilized to achieve controlled hypotension intraoperatively. Dexmedetomidine is a relatively newer agent which works on alpha-2 receptors to decrease sympathetic tone. This paper sought to determine the efficacy of dexmedetomidine for optimizing surgical field visibility in MES. METHODS: A comprehensive search strategy was used in PubMed, SCOPUS, CINAHL, and CENTRAL through August 9, 2022 for this systematic review and meta-analysis. INCLUSION CRITERIA: adult patients undergoing middle ear surgery with dexmedetomidine used for controlled hypotension to improve surgical field visibility. Risk of bias was assessed via Cochrane RoB 2. Meta-analysis of mean difference for surgical field scores and risk ratios for positive surgical field scores were used to compare dexmedetomidine with placebo or other agents. RESULTS: Fourteen studies were included in this review. Statistically significant mean difference was found to favor dexmedetomidine over placebo for Fromme-Boezaart surgical field scores. Statistically significant results were also demonstrated favoring dexmedetomidine over other agents in risk ratio for receiving positive surgical field scores, as well as surgeon and patient satisfaction scores. CONCLUSIONS: Controlled hypotension is an invaluable tool for surgical field visibility. Improved surgical field visibility was observed with dexmedetomidine compared with placebo and various other agents. Risk of sub-optimal bleeding scores was significantly lower with dexmedetomidine. Dexmedetomidine is effective at improving surgical field visibility in middle ear surgery.

Surgical Field Quality in Trans-Nasal Endoscopic Surgeries Using Lignocaine Infusion and Dexmedetomidine Infusion. A Prospective Randomized Control Study.

Trans-nasal endoscopic surgery (TNES) is a helpful diagnostic and therapeutic modality in otorhinolaryngology surgeries and requires controlled hypotension for better visualization of the surgical field. Recent literature shows evidence of intravenous Lignocaine infusion to produce the controlled hypotension. The study aims to assess and compare the effects of Lignocaine (LIG) and Dexmedetomidine (DEX) infusion with respect to surgical field quality. 101 Consenting adult patients undergoing elective TNES were double-blinded, randomly allocated in one of the two groups and received either DEX infusion of 0.5ug/kg/hr (n = 51) or LIG infusion of 1.5 mg/kg/h (n = 50) after a loading dose. Surgical field score (SVF) as the primary outcome and secondary outcomes such as variations in hemodynamic parameters, the requirement for rescue agents and total blood loss were recorded. Both the groups were comparable with respect to patient demographics, total duration of anesthesia and surgery. SVF scores were significantly better in the LIG group during the first 105 min of the surgery (p < 0.05). In response to intubation, hemodynamic parameters were lower in LIG group. The requirement of other adjuvant drugs, total blood loss (166.40 ml vs. 251.17 ml) and extubation time were also significantly lower in the LIG group. The study concludes that intravenous Lignocaine gives a better surgical field in the first 105 min of surgery, comparable hemodynamics and decreased blood loss in patients undergoing TNES as compared to Dexmedetomidine infusion. Hence its role as an agent for controlled hypotension during TNES surgery is promising.

Effects of different levels of controlled hypotension on regional cerebral oxygen saturation and postoperative cognitive function in patients undergoing total knee arthroplasty.

Background: Controlled hypotension technique was usually used to reduce intraoperative bleeding, and it could improve visualization of the surgical field during total knee arthroplasty (TKA). However, inappropriate controlled hypotension, through reducing cerebral blood flow or cerebral perfusion pressure, may cause postoperative cognitive dysfunction (POCD), so it is important to identify the appropriate level of controlled hypotension. Objective: To investigate the effects of different levels of controlled hypotension on regional cerebral oxygen saturation and postoperative cognitive function in patients undergoing TKA. Methods: Patients meeting inclusion criteria were enrolled through preoperative visits and basic information was obtained. The patients were randomly divided into three groups: Group A, MAP was maintained at 90-100% of the baseline; Group B, MAP was maintained at 80-90% of the baseline; Group C, MAP was maintained at 70-80% of the baseline. The MAP, HR, and rSO2 were observed and recorded during the operation. The C-reactive protein (CRP), hemoglobin (Hb) and MMSE score at 1, 3, and 7 days after operation were recorded. SPSS25.0 was used for data analysis. Result: When the MAP had a decrease among the three groups, rSO2 did not decrease significantly, and none of the patients experienced POCD which was measured by MMSE. And there was no correlation between the decline in rSO2 and that in MAP. Conclusion: No POCD was experienced in the three groups, and we recommend that the controlled hypotensive target indicated by MAP was maintained at 70-80% of the baseline which not only decreases intraoperative bleeding and improve the quality of the surgical field, but also is still within safe levels.

Application of Controlled Hypotension During Surgery for Spinal Metastasis.

With advances in tumor treatment, metastasis to bone is increasing, and surgery has become the only choice for most terminal patients. However, spinal surgery has a high risk and is prone to heavy bleeding. Controlled hypotension during surgery has outstanding advantages in reducing intraoperative bleeding and ensuring a clear field of vision, thus avoiding damage to important nerves and vessels. Antihypertensive drugs should be carefully selected after considering the patient's age, different diseases, etc, and a single or combined regimen can be used. Hypotension also inevitably leads to a decrease in perfusion of important organs, so the threshold of hypotension and the maintenance time of hypotension should be strictly limited, and the monitoring of important organs during the operation is particularly important. Information such as blood perfusion, blood oxygen saturation, cardiac output, and neurophysiological conduction potential changes should be obtained in a timely fashion, which will help to reduce the risk of hypotension. In short, when applying controlled hypotension, it is necessary to choose an appropriate threshold and duration, and appropriate monitoring should be conducted during the operation to ensure the safety of the patient.

Rapid Ventricular Pacing as a Safe Procedure for Clipping of Complex Ruptured and Unruptured Intracranial Aneurysms.

Surgical treatment of intracranial aneurysm requires advanced technologies to achieve optimal results. Recently, rapid ventricular pacing (RVP) has been described to be an elegant technique that facilitates clip reconstruction of complex unruptured intracranial aneurysm (uIA). However, there is also a growing need for intraoperative tools to ensure safe clip reconstruction of complex ruptured intracranial aneurysm (rIA). We conducted a retrospective analysis of 17 patients who underwent RVP during surgical reconstruction of complex aneurysms. Nine patients had uIA while eight patients underwent surgery for rIA suffering from consecutive subarachnoid hemorrhage (SAH). Hemodynamic data, critical events, laboratory results, and anesthesia-related complications were evaluated. No complications were reported concerning anesthesia induction and induction times were similar between patients exhibiting uIA or rIA (p = 0.08). RVP induced a significant decline of median arterial pressure (MAP) in both groups (p < 0.0001). However, median MAP before and after RVP was not different in both groups (uIA group: p = 0.27; rIA group: p = 0.18). Furthermore, high-sensitive Troponin T (hsTnT) levels were not increased after RVP in any group. One patient in the rIA group exhibited ventricular fibrillation and required cardiopulmonary resuscitation, but has presented with cardiac arrest due to SAH. Otherwise, no arrhythmias or complications occurred. In summary, our data suggest RVP to be feasible in surgery for ruptured intracranial aneurysms.

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.

Controlled arterial hypotension during resection of cerebral arteriovenous malformations.

BACKGROUND: Resection of cerebral arteriovenous malformations (AVM) is technically demanding because of size, eloquent location or diffuse nidus. Controlled arterial hypotension (CAH) could facilitate haemostasis. We performed a study to characterize the duration and degree of CAH and to investigate its association with blood loss and outcome. METHODS: We retrospectively analysed intraoperative arterial blood pressure of 56 patients that underwent AVM-resection performed by the same neurosurgeon between 2003 and 2012. Degree of CAH, AVM size, grading and neurological outcome were studied. Patients were divided into two groups, depending on whether CAH was performed (hypotension group) or not (control group). RESULTS: The hypotension group consisted of 28 patients, which presented with riskier to treat AVMs and a higher Spetzler-Martin grading. CAH was achieved by application of urapidil, increasing anaesthetic depth or a combination thereof. Systolic and mean arterial blood pressure were lowered to 82 ± 7 and 57 ± 7 mmHg, respectively, for a median duration of 58 min [25% percentile: 26 min.; 75% percentile: 107 min]. In the hypotension group, duration of surgery (4.4 ± 1.3 h) was significantly (p <  0.001) longer, and median blood loss (500 ml) was significantly (p = 0.002) higher than in the control group (3.3 ± 0.9 h and 200 ml, respectively). No case fatalities occurred. CAH was associated with a higher amount of postoperative neurological deficits. CONCLUSIONS: Whether CAH caused neurological deficits or prevented worse outcomes could be clarified by a prospective randomised study, which is regarded as ethically problematic in the context of bleeding. CAH should only be used after strict indication and should be applied as mild and short as possible.

[Effectiveness and safety of tranexamic acid combined with intraoperative controlled hypotension on reducing perioperative blood loss in primary total hip arthroplasty].

OBJECTIVE: To evaluate the effectiveness and safety of tranexamic acid (TXA) combined with intraoperative controlled hypotension (ICH) for reducing perioperative blood loss in primary total hip arthroplasty (THA). METHODS: The clinical data of 832 patients with initial THA due to osteonecrosis of femoral head between January 2017 and July 2020 were retrospectively analyzed. All patients received TXA treatment, and 439 patients (hypotension group) received ICH treatment with an intraoperative mean arterial pressure (MAP) below 80 mm Hg (1 mm Hg=0.133 kPa) while 393 patients (normotension group) received standard general anesthesia with no special invention on blood pressure. There was no significant difference in age, gender, body mass index, American Society of Anesthesiologists (ASA) classification, basic arterial pressure, hip range of motion, internal diseases, preoperative hemoglobin (HB) and hematocrit (HCT), coagulation function, surgical approach, and TXA dosage between the two groups ( P>0.05). The perioperative blood loss and blood transfusion, anesthesia and operation time, hospitalization stay, postoperative range of motion, and complications were recorded and compared between the two groups. The patients were further divided into MAP<70 mm Hg group (group A), MAP 70-80 mm Hg group (group B), and normotension group (group C). The perioperative blood loss and postoperative complications were further analyzed to screen the best range of blood pressure. RESULTS: The intraoperative MAP, total blood loss, dominant blood loss, recessive blood loss, blood transfusion rate and blood transfusion volume, anesthesia time, operation time, and hospitalizarion stay in the hypotension group were significantly lower than those in the normotension group ( P<0.05). The postoperative hip flexion range of motion in the hypotension group was significantly better than that of the normotension group ( Z=2.743, P=0.006), but there was no significant difference in the abduction range of motion between the two groups ( Z=0.338, P=0.735). In terms of postoperative complications, the incidence of postoperative hypotension in the hypotension group was significantly higher than that in the normotension group ( χ 2=6.096, P=0.014), and there was no significant difference in the incidence of other complications ( P>0.05). There was no stroke, pulmonary embolism, or deep vein thrombosis in the two groups, and no patients died during hospitalization. Subgroup analysis showed that there was no significant difference in total blood loss, dominant blood loss, and recessive blood loss in groups A and B during the perioperative period ( P>0.05), which were significantly lower than those in group C ( P<0.05). There was no significant difference in blood transfusion rate, blood transfusion volume, and incidence of acute myocardial injury between 3 groups ( P>0.05); the incidence of acute kidney injury in group A was significantly higher than that in group B, and the incidence of postoperative hypotension in group A was significantly higher than that in groups B and C ( P<0.05), but no significant difference was found between groups B and C ( P>0.05). CONCLUSION: The combination of TXA and ICH has a synergistic effect. Controlling the intraoperative MAP at 70-80 mm Hg can effectively reduce the perioperative blood loss during the initial THA, and it is not accompanied by postoperative complications.

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.

The efficacy of esmolol, remifentanil and nitroglycerin in controlled hypotension for functional endoscopic sinus surgery / Eficácia do esmolol, remifentanil e nitroglicerina na hipotensão controlada para cirurgia sinusal endoscópica funcional

Abstract Introduction Controlled hypotension is a reversible procedure in which the patient's baseline mean arterial blood pressure is reduced by 30% and sustained at 60-70 mmHg during the procedure. It decreases blood loss and provides clear surgical field during the procedures. Objectives The purpose of this study was to compare the efficacy of controlled hypotension agents esmolol, remifentanil, and nitroglycerin in functional endoscopic sinus surgery, in terms of hemodynamic changes and impact on the surgical efficiency. Methods The research was carried out as a cohort study. Patients who underwent functional endoscopic sinus surgery were randomized into 3 groups. Controlled hypotension was achieved with remifentanil (Group R), esmolol (Group E) and nitroglycerin (Group N). The efficacy of the drugs was tested by comparing the length of time with the targeted mean arterial pressure, the amount of anesthetics used, surgical field bleeding score and surgeon's satisfaction. Results Between May to December 2015, 60 patients were included and randomized equally into 3 different study groups. The median of the length of time with the targeted mean arterial pressure was shorter in the Group R when compared with Group E (p = 0.01) and Group N (p = 0.14). The amount of volatile anesthetics used was 25.0 mL (15-51), 43.0 mL (21-105) and 40.0 mL (26-97) in Groups R, E and N, respectively (p < 0.001). While there was more bleeding with nitroglycerin, surgical field bleeding scores were lower in Group R when compared with esmolol (p = 0.001) and nitroglycerin (p < 0.001). The analysis of surgeon's satisfaction scores concluded that surgeons were more satisfied with the group R (100%), when compared with group E (60%) and group N (30%) (p < 0.001). Conclusion Less volatile agent, short time to achieve controlled hypotension, stable blood pressure, lower surgical field bleeding scores and larger length of time with the targeted mean arterial pressure were found as the advantages of Remifentanil. Less costly, efficiency of achieving the targeted median arterial pressure and less postoperative complications were the advantages of nitroglycerin. In functional endoscopic sinus surgery procedures, appropriate controlled hypotensive agents should be selected according to the patients' characteristics and advantages/disadvantages of the drugs.

Resumo Introdução Hipotensão controlada é um procedimento reversível no qual a pressão arterial média basal do paciente é reduzida em 30% e mantida em 60-70 mmHg durante o procedimento. Isso diminui a perda de sangue e propicia um campo cirúrgico limpo durante os procedimentos. Objetivo Comparar agentes usados para hipotensão controlada: esmolol, remifentanil e nitroglicerina em cirurgia sinusal endoscópica funcional, em termos de alterações hemodinâmicas e impactos na eficácia cirúrgica. Método O estudo foi feito como de coorte. Pacientes submetidos à cirurgia sinusal endoscópica funcional foram randomizados em 3 grupos. A hipotensão controlada foi feita com remifentanil (Grupo R), esmolol (Grupo E) e nitroglicerina (Grupo R). A eficácia dos medicamentos foi testada com a comparação do período de tempo com a pressão arterial média desejada, a quantidade de anestésicos usados, o escore de sangramento no campo cirúrgico e a satisfação do cirurgião. Resultados Entre maio e dezembro de 2015, 60 pacientes foram incluídos e randomizados igualmente nos três grupos de estudo. A mediana do período com a pressão arterial desejada foi menor no Grupo R quando comparado ao Grupo E (p = 0,01) e Grupo N (p = 0,14). A quantidade de anestésicos voláteis usados foi de 25,0 mL (15 ± 51), 43,0 mL (21 ± 105) e 40,0 mL (26 ± 97) nos Grupos R, E e N, respectivamente (p < 0,001). Houve mais sangramento com nitroglicerina e escores de sangramento no campo cirúrgico foram menores no Grupo R quando comparados com esmolol (p = 0,001) e nitroglicerina (p < 0,001). A análise dos escores da satisfação do cirurgião concluiu que os cirurgiões estavam mais satisfeitos com o grupo R (100%) quando comparados ao grupo E (60%) e o grupo N (30%) (p < 0,001). Conclusão Agente menos volátil, pouco tempo para obter a hipotensão controlada, pressão arterial estável, menor escore de sangramento no campo cirúrgico e período de pressão arterial desejada curto foram considerados como vantagens do remifentanil. Menor custo, eficácia de obtenção da pressão arterial média desejada e menos complicações pós-operatórias foram as vantagens da nitroglicerina. Nos procedimentos de cirurgia sinusal endoscópica funcional, os agentes apropriados para obtenção de hipotensão controlada devem ser selecionados de acordo com as características dos pacientes e as vantagens/desvantagens dos fármacos.

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.