Controlled hypotension: a guide to drug choice

ALM Resuscitation With Brain and Multiorgan Protection for Far-Forward Operations: Survival at Hypotensive Pressures

INTRODUCTION

Non-compressible torso hemorrhagic (NCTH) shock is the leading cause of potentially survivable trauma on the battlefield. New hypotensive drug therapies are urgently required to resuscitate and protect the heart and brain following NCTH. Our aim was to examine the strengths and limitations of permissive hypotension and discuss the development of small-volume adenosine, lidocaine, and Mg2+ (ALM) fluid resuscitation in rats and pigs.

MATERIALS AND METHODS

For review of permissive hypotension, a literature search was performed from inception up to November 2023 using PubMed, Cochrane, and Embase databases, with inclusion of animal studies, clinical trials and reviews with military and clinical relevance. For the preclinical study, adult female pigs underwent laparoscopic liver resection. After 30 minutes of bleeding, animals were resuscitated with 4 mL/kg 3% NaCl ± ALM bolus followed 60 minutes later with 4 h 3 mL/kg/h 0.9% NaCl ± ALM drip (n = 10 per group), then blood transfusion. Mean arterial pressure (MAP) and cardiac output (CO) were continuously measured via a left ventricular pressure catheter and pulmonary artery catheter, respectively. Systemic vascular resistance (SVR) was calculated using the formula: 80 × (MAP - CVP)/CI. Oxygen delivery was calculated as the product of CO and arterial oxygen content.

RESULTS

Targeting a MAP of ∼50 mmHg can be harmful or beneficial, depending on how CO and SVR are regulated. A theoretical example shows that for the same MAP of 50 mmHg, a higher CO and lower SVR can lead to a nearly 2-fold increase in O2 supply. We further show that in animal models of NCTH, 3% NaCl ALM bolus and 0.9% NaCl ALM drip induce a hypotensive, high flow, vasodilatory state with maintained tissue O2 supply and neuroprotection. ALM therapy increases survival by resuscitating the heart, reducing internal bleeding by correcting coagulopathy, and decreasing secondary injury.

CONCLUSIONS

In rat and pig models of NCTH, small-volume ALM therapy resuscitates at hypotensive pressures by increasing CO and reducing SVR. This strategy is associated with heart and brain protection and maintained tissue O2 delivery. Translational studies are required to determine reproducibility and optimal component dosing. ALM therapy may find wide utility in prehospital and far-forward military environments.

Addition of Dexmedetomidine to Propofol Anesthesia for Middle-Ear Surgeries: A Prospective Randomized Double-Blind Study

Background Middle-ear surgery commonly performed under a microscope requires a bloodless field provided by hypotensive anesthesia. Our objective was to study the effects of dexmedetomidine on propofol consumption and intraoperative hemodynamic stability. Methods One hundred adults undergoing elective middle-ear surgery were randomized into two groups. The propofol+dexmedetomidine group (Group PD) received a loading dose of dexmedetomidine 1μg/kg in 10ml normal saline over 10min followed by infusion of the same at 0.5μg/kg/h. Propofol-only group (Group P) received 10ml normal saline over 10min followed by an infusion of the same. General anesthesia was induced with intravenous morphine, propofol, and vecuronium, and maintained with propofol, oxygen, and N2O. During microscope use, we aimed to maintain mean arterial pressure (MAP) within 60-69mmHg. Results There was no significant difference in the mean (SD) consumption of propofol [Group P 8.6 (2.1)mg/kg/h vs Group PD 8.1 (1.5)mg/kg/h, P=0.172]. The induction dose of propofol was significantly less in Group PD [1.8 (0.3) vs 2 (0.4)mg/kg, P<0.001]. Except for the baseline value, the heart rate was significantly lower in Group PD, P<0.001. The time duration during which MAP was within 60-69mmHg was higher in Group P [37.5 (36.8) vs 30.9 (38.3)min] though the difference was not statistically significant. The recovery was delayed in Group PD [25.4 (8.6) vs 17.6 (4.9)min, P<0.001]. Group PD had a significantly better operative field, P=0.0003. Conclusion The addition of dexmedetomidine did not reduce propofol consumption but reduced the induction dose of propofol. Propofol and dexmedetomidine combination provided comparable mean arterial pressure and better operative field but caused delayed recovery.

Assessing the Risks and Benefits of Hypotensive Anesthesia and Piezosurgical Instruments in Bimaxillary Surgery

The challenge in bimaxillary surgery lies in significant intraoperative bleeding, prompting various strategies to minimize blood loss. Among the methods considered for controlling intraoperative bleeding, hypotensive anesthesia and the use of piezosurgical instruments (Osada, Tokyo, Japan) have been explored. However, hypotensive anesthesia may have adverse effects on cardiac function, and surgical time is likely to be prolonged when using piezosurgical instruments. This study retrospectively examined whether the combined use of hypotensive anesthesia and piezosurgical instruments reduces intraoperative bleeding and whether the combination impacts cardiac function. The combination of hypotensive anesthesia and piezosurgical instruments significantly reduced intraoperative bleeding. Furthermore, the combination was associated with a significantly higher incidence of tachycardia, particularly with the use of nicardipine. Additionally, the combination significantly lengthened the duration of the surgery and may have increased the burden on cardiac function. Landiolol was effectively employed to manage tachycardia. When selecting hypotensive anesthesia as a means to limit bleeding, proactive preparation and preventive small-dose administration of landiolol could be beneficial in managing the potential occurrence of tachycardia.

Optimizing Visualization in Shoulder Arthroscopy: An Evidence-Based Guide

Advances in arthroscopy have contributed toward improved understanding and management of diverse pathological conditions in the shoulder. As a result, arthroscopy is often preferred by both patients and surgeons. However, surgery can be complicated by limited visualization. Techniques to improve visualization include patient and portal positioning, mechanical débridement, radiofrequency ablation, epinephrine added to irrigation fluid, tranexamic acid administration, and controlled hypotensive anesthesia. Despite published literature on each, a thorough understanding of the evidence supporting these techniques and adjuvants is essential to interpret the clinical utility of each.

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.

Peroperative Cooling in Rhinoplasty: Does it Differ?

The main causes of ecchymosis and edema are osteotomy (bone manipulation), dissection of subcutaneous tissue, and skin manipulation in the rhinoplasty procedure. Eyelid edema following surgery can potentially affect visual acuity, particularly during the initial twenty-four hours after the procedure. These may also delay the patient's return to their normal social life therefore hampering their quality of life. Various surgical and medical methods have been reported to address these issues. This study aimed to compare the effects of using cold saline (0-4 °C) versus room temperature saline (20-25 °C) irrigation throughout the surgery on postoperative edema, ecchymosis, and pain. Fifty patients who underwent open-approach primary rhinoplasty between August 2022 and August 2023 at a tertiary academic center were included. Fifty patients were randomly divided into two groups depending on using cold saline (0-4 °C) (group 1) or room temperature saline (20-25 °C) (group 2) during surgical site irrigation. Patients were assessed for pain, edema, and bruising using a VAS (Visual Analog Scale) on the second and seventh postoperative days. Visual analog score (VAS) was used for subjective outcome analyses. Each patient scored the severity of their periorbital ecchymosis on day two and seven. Periorbital ecchymosis was also evaluated on the second and seventh postoperative days using the SPREE (Surgeon Periorbital Rating of Edema and Ecchymosis) scale. On the second postoperative day, the VAS pain score in group 1, where cold water was used, was found to be statistically and significantly different from the control group (group 2) (p < 0.05). However, there was no statistically significant difference between both groups when comparing the VAS pain scores on the seventh postoperative day. Regarding the VAS ecchymosis score on the seventh postoperative day, there was a statistically significant difference favoring group 1 (p < 0.05). The SPREE scale data also indicated that group 1 had significantly lower scores on the seventh day (p < 0.05). While the SPREE scores on the second day were lower in group 1 than in group 2, this difference did not reach statistical significance (p = 0.061). The findings from our study show that cold saline irrigation may contribute to intraoperative hemostasis by inducing local vasoconstriction. We observed that intraoperative bleeding decreased with the use of cold saline. This approach has the potential to improve patient satisfaction and overall quality of life by reducing postoperative ecchymosis without significantly increasing the cost of the surgical procedure.Level of Evidence III This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

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.

Comparative study between remifentanil (or fentanyl) and dexmedetomidine for the analgesia of rhinoplasty: A meta-analysis of randomized controlled trials

BACKGROUND

Remifentanil (or fentanyl) and dexmedetomidine may have some potential to improve the analgesia of rhinoplasty, and this meta-analysis aims to compare their efficacy for the analgesia of rhinoplasty.

METHODS

PubMed, Embase, Web of Science, EBSCO, and Cochrane Library databases were systematically searched, and we included randomized controlled trials (RCTs) assessing the analgesic effect of remifentanil (or fentanyl) versus dexmedetomidine for rhinoplasty.

RESULTS

Four RCTs were finally included in the meta-analysis. In patients undergoing rhinoplasty, remifentanil (or fentanyl) infusion and dexmedetomidine infusion resulted in similar good patient satisfaction (odd ratio [OR] = 2.71; 95% confidence interval [CI] = 0.63 to 11.64; P = .18), good surgeon satisfaction (OR = 1.68; 95% CI = 0.02 to 181.40; P = .83), extubation time (mean difference [MD] = 7.56; 95% CI = -11.00 to 26.12; P = .42), recovery time (MD = -2.25; 95% CI = -23.41 to 18.91; P = .83), additional analgesic requirement (OR = 0.16; 95% CI = 0 to 8.65; P = .37) and adverse events (OR = 8.50; 95% CI = 0.47 to 153.30; P = .15).

CONCLUSIONS

Remifentanil (or fentanyl) and dexmedetomidine may have comparable analgesia for patients undergoing rhinoplasty.

Comparison of the effects of dexmedetomidine and nitroglycerin on cerebral oxygen saturation using near-infrared spectroscopy in patients undergoing controlled hypotensive anaesthesia: A randomised controlled non-inferiority trial

Background and Aims

There is limited literature wherein the hypotensive drugs have been compared to know the cerebral effects by monitoring regional cerebral oxygen saturation (rScO2). This study aimed to compare the effects of dexmedetomidine and nitroglycerin on rScO2 during controlled hypotensive anaesthesia using near-infrared spectroscopy (NIRS). The primary objective was to evaluate the non-inferiority of dexmedetomidine versus nitroglycerin in the occurrence of cerebral desaturation events (CDEs) during hypotensive anaesthesia.

Methods

Adult patients scheduled to undergo head and neck surgery under general anaesthesia randomised to receive either dexmedetomidine or nitroglycerin infusion for controlled hypotensive anaesthesia. Cerebral oximetry was monitored with NIRS, and data regarding CDEs, bilateral rScO2, and peri-operative haemodynamics were collected. Continuous data were analysed using unpaired Student's t-tests except for intra-group analyses, which were analysed using paired t-tests. Categorical data were analysed using the Chi-square test. For comparison of time to CDEs, Kaplan-Meier survival analysis with log-rank test was performed.

Results

Of the 82 patients in both groups, CDEs were observed in 15 patients each. A decrease from baseline by 20% was observed in three patients: one in Group N and two in Group D. Statistically, there was an equal risk of getting CDEs in the groups. The time to CDE was comparable (P > 0.05). The difference in heart rate was statistically significant (P < 0.001).

Conclusion

Dexmedetomidine is non-inferior to nitroglycerin in terms of the occurrence of cerebral desaturation events when used for controlled hypotensive anaesthesia in head and neck surgeries.

Premedication with intranasal versus intravenous dexmedetomidine for hypotensive anesthesia during functional endoscopic sinus surgery in adults: A randomized triple-blind trial

Functional Endoscopic Sinus Surgery (FESS) has been performed under controlled hypotension to increase operating field visibility. Intranasal (IN) dexmedetomidine is easy, noninvasive, and possesses lower C max, accompanied by lower pharmacodynamic action, including hypotension, bradycardia, and sedation. This trial aimed to compare IN and intravenous (IV) dexmedetomidine for hypotensive anesthesia during FESS. This randomized, controlled, triple-blinded clinical trial involved sixty cases scheduled for FESS. Patients were divided into two equal groups by random manner. 45-60 min before anesthesia induction, group IN: received 1 μg/kg IN dexmedetomidine diluted in 10 ml of saline 0.9 % intranasally preoperative. Group IV: received 1 μg/kg dexmedetomidine diluted in 10 ml of saline 0.9 % infused over 10 min. The primary outcome was the total amount of administered atropine. The secondary outcomes included hemodynamic, through 1 h before surgery, intraoperatively and postoperatively at different time intervals. The quality of the operative field, sedation, adverse reactions and hemostatic stuffing after FESS were also assessed. The total amount of consumed atropine decreased significantly in group IN compared to group IV. Preoperative Ramsay Sedation scores at T0, T5, T50 and T60 were comparable between the two groups, while at T10, T15, T20, T30, and T40 were lower significantly in the IN group compared with the IV group. Preoperative mean arterial blood pressure at T0, T5 and T60 had comparable differences across both groups while reduced at T10 to T 45 significantly in the IV group than IN group. Both groups had comparable satisfaction, postoperative Ramsey sedation, hemostatic suffering, quality of operative field and complications. In conclusion, IN dexmedetomidine administration is relatively simple and appropriate; moreover, it decreases first-pass metabolism. Onset is prolonged relative to IV dosing; thus, it should be administered nearly 1 h before surgery and recommended in adult patients as they require minor sedation preoperatively.

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.

Intraoperative hypotension and postoperative outcomes: a meta-analysis of randomised trials

INTRODUCTION

Intraoperative hypotension is associated with adverse postoperative outcomes; however these findings are supported only by observational studies. The aim of this meta-analysis of randomised trials was to compare the postoperative effects permissive management with targeted management of intraoperative blood pressure.

METHODS

We searched PubMed, Cochrane, and Embase up to June 2023 for studies comparing permissive (mean arterial pressure ≤60 mm Hg) with targeted (mean arterial pressure >60 mm Hg) intraoperative blood pressure management. Primary outcome was all-cause mortality at the longest follow-up available. Secondary outcomes were atrial fibrillation, myocardial infarction, acute kidney injury, delirium, stroke, number of patients requiring transfusion, time on mechanical ventilation, and length of hospital stay.

RESULTS

We included 10 randomised trials including a total of 9359 patients. Mortality was similar between permissive and targeted blood pressure management groups (89/4644 [1.9%] vs 99/4643 [2.1%], odds ratio 0.88, 95% confidence interval [CI], 0.65-1.18, P=0.38, I2=0% with nine studies included). Atrial fibrillation (102/3896 [2.6%] vs 130/3887 [3.3%] odds ratio 0.71, 95% CI 0.53-0.96, P=0.03, I2=0%), and length of hospital stay (mean difference -0.20 days, 95% CI -0.26 to -0.13, P<0.001, I2=0%) were reduced in the permissive management group. No significant differences were found in subgroup analysis for cardiac and noncardiac surgery.

CONCLUSION

Pooled randomised evidence shows that a target intraoperative mean arterial pressure ≤60 mm Hg is not associated with increased mortality; nevertheless it is surprisingly associated with a reduced rate of atrial fibrillation and of length of hospital stay.

SYSTEMATIC REVIEW PROTOCOL

PROSPERO CRD42023393725.

Tourniquet-less arthroscopic anterior cruciate ligament reconstruction: a technical guide & narrative review of the evidence

Arthroscopic anterior cruciate ligament reconstruction (ACLR) is often performed with the use of a thigh tourniquet. Surgeons believe this helps improve visualisation and reduce operative time. However, tourniquet use has been associated with many complications including increased pain, neurovascular injury, venous thromboembolism, haematoma formation, and others. In this article, we describe a method allowing comparable arthroscopic visualisation to be achieved without the aid of a tourniquet for ACLR procedures. The literature evidence relating to this technique as well as tourniquet use for ACLR is also reviewed. Tourniquet-less ACLR can be achieved through the combined application of hypotensive anaesthesia, intravenous tranexamic acid, and use of adrenaline-supplemented irrigation fluid and local anaesthetic. Performing ACLR without a tourniquet avoids the risks associated with its use and reduces the severity of post-operative haemarthrosis which may contribute to the patient's pain and limit their ability to perform their rehabilitation exercises.

Efficacy of Isoflurane-Remifentanil versus Propofol-Remifentanil on Controlled Hypotension and Surgeon Satisfaction in Rhinoplasty: A Single-Blind Clinical Trial Study

Background

Rhinoplasty is a complex but popular surgery in Iran. The main complications of the surgery are post-operative bleeding and nasal septal hematoma due to poor intra-operative controlled hypertension. This study aimed to compare the efficacy of isoflurane-remifentanil (I-R) versus propofol-remifentanil (P-R) to induce controlled hypotension and to assess surgeon satisfaction with each of these combinations during rhinoplasty.

Methods

In 2020-2021, a single-blind clinical study was conducted on 98 patients aged 18-50 years undergoing rhinoplasty at Mother and Child Hospital (Shiraz, Iran). Patients were randomly divided into P-R (n=48) and I-R (n=50) groups. Changes in systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and heart rate (HR) were assessed during surgery and in the recovery room. A questionnaire was used to evaluate the level of surgeon satisfaction. Data were analyzed using independent samples t test, Chi-square test, and repeated measures ANOVA with SPSS software. P<0.05 was considered statistically significant.

Results

Five minutes after anesthesia induction, the P-R combination had a greater effect on reducing SBP (P=0.010), DBP (P=0.007), MAP (P=0.003), and HR (P=0.026) than I-R. However, from the 40^th minute to the end of surgery and after 30 minutes of recovery, the I-R combination had a slightly better effect on blood pressure reduction than P-R. There was no difference in surgeon satisfaction with either of the two drug combinations.

Conclusion

Both P-R and I-R combinations are recommended to induce hypotension during rhinoplasty. However, I-R is more effective than P-R in inducing the desired controlled hypotension.

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.

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.

Dexmedetomidine versus remifentanil for controlled hypotension under general anesthesia: A systematic review and meta-analysis

This meta-analysis aimed to analyze and compare the efficacy and safety of remifentanil and dexmedetomidine applied respectively for controlled hypotension under general anesthesia. We searched the Cochrane Library, PubMed, EMBASE, Web of Science, CNKI, SinoMed, Wanfang, and VIP databases, as well as dissertations and conference papers, to obtain randomized controlled trials comparing remifentanil and dexmedetomidine applied respectively for controlled hypotension before August 23, 2021. The primary outcomes included hemodynamic profiles, surgical field score, and blood loss. Extubation time, sedation and pain score at the PACU, and perioperative adverse events were the secondary outcomes. Nine randomized controlled trials with 543 patients (272 in the dexmedetomidine group and 271 in the remifentanil group) were eventually included. This meta-analysis indicated no significant difference between dexmedetomidine and remifentanil in terms of surgical field score, blood loss, minimum values of mean arterial pressure (MD 0.24 with 95% CI [-1.65, 2.13], P = 0.80, I2 = 66%) and heart rate (MD 0.42 [-1.33, 2.17], P = 0.64, I2 = 40%), sedation scores at the PACU (MD -0.09 [-0.69, 0.50], P = 0.76, I2 = 92%), and incidence of bradycardia (OR 2.24 [0.70, 7.15], P = 0.17, I2 = 0%). Compared with remifentanil, dexmedetomidine as the controlled hypotensive agent showed a lower visual analogue score at the PACU (MD -1.01 [-1.25, -0.77], P<0.00001, I2 = 0%) and incidence of shivering (OR 0.22 [0.08, 0.60], P = 0.003, I2 = 0%), nausea, and vomiting (OR 0.34 [0.13, 0.89], P = 0.03, I2 = 0%). However, extubation time was shorter in the remifentanil group (MD 3.34 [0.75, 5.93], P = 0.01, I2 = 90%). In conclusion, dexmedetomidine and remifentanil are both effective in providing satisfactory controlled hypotension and surgical conditions. Dexmedetomidine is better in easing postoperative pain at the PACU and reducing the occurrence of shivering, nausea, and vomiting. Meanwhile, remifentanil is a fast-track anesthesia with a shorter extubation time. Given the limitations of this meta-analysis, further studies are needed for a more definitive comparison of the efficacy and safety of dexmedetomidine and remifentanil.

Bloodless surgery in urologic oncology: A review of hematologic, anesthetic, and surgical considerations

The urologic oncology patient who refuses blood transfusion can present unique challenges in perioperative blood management. Since blood loss and associated transfusion can be expected in many complex urologic oncology surgeries, a multidisciplinary approach may be required for optimal outcomes. Through collaboration with the hematologist, anesthesiologist, and urologist, various techniques can be employed in the perioperative phases to minimize blood loss and the need for transfusion. We review the risks and benefits of these techniques and offer recommendations specific to the urologic oncology patient.

Hearing outcomes and patient satisfaction after stapes surgery: local versus general anaesthesia

Objective

Otosclerosis is a frequent ear disorder causing a stapedo-ovalar ankylosis and conductive hearing loss. Stapedoplasty, performed under both general (GA) and local anaesthesia (LA), is the most advisable surgical solution. Auditory recovery relies on the patient's conditions and on the intervention itself. The aim of our work was to compare hearing outcomes with stapedoplasty performed under GA or LA and to investigate patients' compliance to both methods.

Methods

Fifty-five otosclerotic patients underwent stapedoplasty both under GA (32/55) and LA (23/55). Pre- and post-operative air and bone tone audiometry threshold values as well as the air-bone gap and its closure score, were analysed. All patients filled in a satisfaction questionnaire regarding their concern and level of appreciation of the type of anaesthesia.

Results and conclusions

Our data show that the auditory results with stapedoplasty are good and do not differ between LA and GA. Even considering the advantages and limits of the two methods, one cannot favour one or the other type of anaesthesia. Finally, the patient's satisfaction cannot be considered a criterion of choice, since this was found to be high in both cases.

Clinical Implication of the Acumen Hypotension Prediction Index for Reducing Intraoperative Haemorrhage in Patients Undergoing Lumbar Spinal Fusion Surgery: A Prospective Randomised Controlled Single-Blinded Trial

We investigated the clinical implication of the Hypotension Prediction Index (HPI) in decreasing amount of surgical haemorrhage and requirements of blood transfusion compared to the conventional method (with vs. without HPI monitoring). A prospective, randomised controlled-trial of 19- to 73-year-old patients (n = 76) undergoing elective lumbar spinal fusion surgery was performed. According to the exclusion criteria, the patients were divided into the non-HPI (n = 33) and HPI (n = 35) groups. The targeted-induced hypotension systolic blood pressure was 80−100 mmHg (in both groups), with HPI > 85 (in the HPI group). Intraoperative bleeding was lower in the HPI group (299.3 ± 219.8 mL) than in the non-HPI group (532 ± 232.68 mL) (p = 0.001). The non-HPI group had a lower level of haemoglobin at the end of the surgery with a larger decline in levels. The incidence of postoperative transfusion of red blood cells was higher in the non-HPI group than in the HPI group (9 (27.3%) vs. 1 (2.9%)). The use of HPI monitoring may play a role in providing timely haemodynamic information that leads to improving the quality of induced hypotension care and to ameliorate intraoperative surgical blood loss and postoperative demand for blood transfusion in patients undergoing lumbar fusion surgery.

Improving Postoperative Acute Kidney Injury Rates Following Primary Total Joint Arthroplasty

BACKGROUND

Perioperative hip and knee arthroplasty complications remain a significant clinical and financial burden. Our institution has shifted to developing protocols to decrease these perioperative complications. This study focuses on acute kidney injury (AKI) rate status post primary total joint arthroplasty (TJA). Current literature demonstrates a 2%-15% incidence of AKI following TJA. However, there is a paucity of published literature on protocols that have effectively reduced AKI rates following TJA. The purpose of this study is to evaluate the effect that our institutionally developed perioperative renal protocol had on the postoperative AKI rates.

METHODS

A retrospective cohort study was performed. Patient demographics, baseline creatinine, and postoperative creatinine values during the patient's hospitalization were collected and analyzed. The preintervention cohort data contained all patients at our institution who underwent a primary TJA from November 1, 2016 to January 1, 2018. The postintervention cohort included all primary TJA patients from July 1, 2018 to February 2, 2020. AKI was defined using the AKI Network classification system comparing baseline and postoperative creatinine values. A multivariate analysis was performed to determine the statistical significance of our results.

RESULTS

Before intervention 1013 patients underwent a primary TJA with 68 patients developing an AKI postoperatively. After intervention 2169 patients underwent primary TJA with 90 patients developing an AKI (6.71% vs 4.15%; P = .0015, odds ratio = 0.59, 95% confidence interval = 0.42-0.82).

CONCLUSION

This study demonstrated that implementation of a perioperative renal protocol can significantly reduce AKI rates. A reduction in AKI rates following TJA will result in improved outcomes and secondarily decrease the financial impact of postoperative complications seen following TJA.

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.

Establishment of a risk index for early complications after trans-canal endoscopic ear surgery

PURPOSE

This study aimed to determine the risk factors associated with early postoperative complications of trans-canal endoscopic ear surgery (TEES), then to develop a risk index.

MATERIALS AND METHODS

This single-institution retrospective study reviewed TEESs from January 1, 2017, to December 31, 2019 in a tertiary hospital. In the derivation cohort, univariable and multivariable logistic regression were performed to identify factors significantly associated with early postoperative complications of TEES. Then these parameters were integrated into a trans-canal endoscopic ear surgery risk index (TEESRI). The performance of TEESRI was compared with that of the American Society of Anesthesiologists (ASA) classification using the validation cohort.

RESULTS

932 TEESs were enrolled in total and 151 (16.2%) developed early postoperative complications. In the derivation set, 8 factors including state of the opposite ear and presence of nasal or pharyngeal diseases were found to be independently associated with the occurrence of early postoperative complications on multivariable regression analysis [area under the curve (AUC), 0.806; 95% confidence interval (CI), 0.765-0.848]. Using the validation cohort, the AUC of the TEESRI was 0.776 [95%CI, 0.711-0.842], with a sensitivity of 82.2% and specificity of 65.5%, while the AUC of the ASA classification was 0.512 (95%CI, 0.421-0.603). The TEESRI outperformed the ASA classification when evaluating the risk for early postoperative complications of TEES.

CONCLUSIONS

Based on the 8 risk factors, the TEESRI was established with satisfactory predicting capacity. Surgeons should pay extra attention to the risk factors in the TEESRI, when treating patients.

Effect of intraoperative blood pressure on incidence of hematoma in breast reduction mammoplasty

BACKGROUND

Postoperative hematomas are among the most frequent complications following breast reduction mammoplasty (BRM). Intraoperative hypotension has been implicated in the development of postoperative hematomas following breast reduction. In this study, we performed a retrospective, propensity-matched analysis of patients undergoing primary breast reduction to determine the relationship between intraoperative blood pressure and the development of a postoperative hematoma.

METHODS

A retrospective review of all patients that underwent BRM at a single institution from 2017 to 2019 (n = 563) was conducted. Patients who developed a postoperative hematoma were propensity matched to two controls based on body mass index (BMI) and age. The mean systolic blood pressure (SBP) and average mean arterial pressure (MAP) were recorded for each third of the operation. Data were analyzed using conditional logistic regression.

RESULTS

Thirty-two patients that developed postoperative hematomas were propensity matched to 64 controls. There was no difference in baseline SBP, diastolic blood pressures, or prevalence of hypertension between groups. There was no significant difference in average SBP or MAP between groups. The average MAP during the first third of the procedure was found to be lower in patients who developed a hematoma (69 vs. 72 mmHg), which approached significance at p = 0.08. Closed suction drains were used in 53% of the hematoma group and 78% of the control group (p = 0.02).

CONCLUSION

There does not appear to be an association between intraoperative blood pressure and the incidence of hematoma when comparing patients who developed hematomas after BRM to propensity-matched controls.

Effects of esmolol continuous infusion on blood loss in patients undergoing posterior lumbar internal fixation surgery: A prospective randomized study

Objective

To determine the intravenous (i.v.) dose of esmolol needed to attenuate blood loss in patients undergoing posterior lumbar internal fixation (PLIF) surgery.

Methods

This study randomized patients to either the E5 or E10 group. Patients in the E5 group received a 0.25 mg/kg i.v. loading dose of esmolol before anaesthesia, followed by an infusion of 5 µg/kg/min throughout the operation. Patients in the E10 group received a 0.5 mg/kg i.v. loading dose of esmolol before anaesthesia, followed by an infusion of 10 µg/kg/min throughout the operation.

Results

The study analysed 33 patients: 16 in the E5 group and 17 in the E10 group. The mean ± SD blood loss at the end of surgery was significantly greater in the E5 than E10 group (586.3 ± 160.1 versus 347.7 ± 138.0 ml, respectively). The total amount of patient-controlled analgesia (PCA) used was significantly higher in the E5 than E10 group at 8 (26.1 ± 12.0 versus 17.5 ± 8.3 ml, respectively), 24 (58.4 ± 21.3 versus 44.1 ± 16.2 ml, respectively) and 48 h after surgery (90.0 ± 22.5 versus 69.3 ± 22.1 ml, respectively).

Conclusion

A continuous infusion of 10 µg/kg/min of esmolol can safely reduce blood loss during PLIF surgery. It was also shown to reduce postoperative PCA consumption.

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.

Preventing Acute Kidney Injury and Hypotension After Elective Total Joint Arthroplasty Is Possible: An Update to an Established Multidisciplinary Protocol

INTRODUCTION

Based on preoperative and perioperative risk factors that have been found to correlate with the development of acute kidney injury (AKI), our institution developed a protocol aimed at managing and improving outcomes in all elective THA and TKA patients. This article highlights the continued success and growth of our protocol aimed at decreasing AKI and hypotension in elective total joint arthroplasty patients.

METHOD

A multidisciplinary team comprising orthopaedic surgeons, nephrologists, anesthesiologists, cardiologists, and internal medicine hospitalists created a comprehensive protocol aimed at decreasing complications after elective joint arthroplasty and improving clinical outcomes across multiple hospitals. Patient demographics, hospital length of stay, readmission rates, mortality, and postoperative AKI and hypotension incidences were recorded and compared between preprotocol phase I (initial protocol implementation) and phase II (protocol expansion across 10 hospitals) patient cohorts.

RESULTS

Overall, 3,222 patients over 56 months and 10 hospitals were included. Our phase II AKI rate (0.6%) was significantly lower than our preprotocol rate (6.2%, P < 0.01) and statistically similar to our phase I rate (1.2%, P = 0.61). Our hypotension rate in phase II (6.8%) was significantly lower than our preprotocol rate (12.7%, P < 0.01) but statistically similar to our phase I rate (5.9%, P = 0.40). Furthermore, a significant decrease was observed in hospital length of stay (P < 0.01) over time, but no difference was observed in readmission (P = 0.59) and mortality rates (P = 1.00) over time.

DISCUSSION

This protocol-driven interventional study provides a detailed and successful multidisciplinary method to manage and decrease rates of AKI and hypotension in a large patient cohort across multiple hospital centers.

Gender Differences do not Influence the Blood Coagulopathy in Patients Undergoing Total Knee Arthroplasty: A Retrospective Thromboelastography Analysis

Objective

Deep vein thrombosis (DVT) is one of the severe complications after total knee arthroplasty (TKA). Gender has been considered to influence the incidence of the thrombosis formation in TKA patients. However, it remains controversial which gender would be more prone to form thrombosis. The aim of this study was to assess the effects of gender differences on coagulation status after TKA via the thromboelastography (TEG).

Methods

A total of 57 male patients who underwent primary TKA from September 2015 to January 2021 were included in this study. According to the matching principle of age, body mass index (BMI), and anticoagulation treatment, 60 female patients were selected. The conventional coagulation tests, routine blood tests, and thromboelastography were conducted before the operation, 1 day and 7 days after the operation. In addition, Doppler ultrasound was also performed 1 day before the operation and at the 7 days after the operation. The parameters of conventional coagulation tests, routine blood tests, and thromboelastography were compared between the two groups.

Results

There were no significant differences in the blood transfusion rate, the incidence of DVT during the perioperative period, D-dimer (D-D), fibrin degradation products (FDP), hemoglobin (HB), hematocrit (HCT), prothrombin time (PT), activated partial thromboplastin time (APTT), and C-reactive protein (CRP) at any corresponding time point between the male group and the female group (P > .05). There were no significant differences in neutrophil-to-lymphocyte ratio (NLR) preoperatively; however, there were significant differences in NLR 1 day after the surgery and 7 days after the surgery between the two groups (P < .05). There were significant differences in reaction time (R) and α angle 1 day after the surgery between the two groups (P < .05), but there were no significant differences in other TEG indexes at any corresponding time point between the two groups (P > .05). Binary logistic regression analysis demonstrated that gender, age, BMI, tourniquet application time were not independent predictors (P > .05).

Conclusion

Gender differences have no significant influence in TKA patients with regard to conventional coagulation tests and thromboelastography.

Dynamic thiol/disulphide balance in patients undergoing hypotensive anesthesia in elective septoplasties

OBJECTIVE

We aimed to investigate the effects of hypotensive anaesthesia on oxidative stress with serum thiol/disulphide balance in patients undergoing elective septoplasty procedures under general anaesthesia.

METHODS

Seventy-two patients between the ages of 18-60, with a physical condition I -II, according to the American Society of Anesthesiologists, were included in this prospective observational study. Septoplasty was chosen for standard surgical stress. According to the maintenance of anaesthesia, patients were divided into the groups as Hypotensive Anaesthesia (n = 40) and Normotensive Anaesthesia (n = 32). Serum thiol/disulphide levels were measured by the method developed by Erel & Neşelioğlu.

RESULTS

The native thiol and total thiol values of both groups measured at the 60th min intraoperatively were significantly lower than the preoperative values (both P < .01). Intraoperatively, at the 60th min, there was no significant difference in terms of post-native thiol and post-total thiol levels between hypotensive and normotensive anaesthesia groups (P = .68 and .81, respectively). Age >40 years and female gender were found to have a significant effect on dynamic oxidative stress (P = .002 and .001, respectively).

CONCLUSION

This pilot study has found that hypotensive anaesthesia had no adverse effect on dynamic thiol/disulphide balance in elective surgeries.

Comparison of epidural, spinal, and saddle block for holmium laser enucleation of prostate (HoLEP): A prospective randomized, comparative study

BACKGROUND

Holmium laser enucleation of the prostate (HoLEP) has become an important treatment modality for benign prostate hypertrophy. The aim of the present study was to compare regional anesthesia methods for HoLEP operation and to determine the optimal technique.

METHODS

Sixty patients with American Society of Anesthesiologists scores of I-III were randomly allocated into 3 groups. Patients in group E received an epidural block with 75 mg of bupivacaine plus 50 μg of fentanyl. In group S, 15 mg of bupivacaine and 50 μg fentanyl were used for spinal anesthesia. In group SA, patients received saddle block with 15 mg of bupivacaine and 50 μg of fentanyl.

RESULTS

Time to T10 dermatome block and to maximal level block were longest in group E (P < .05), and maximal sensorial block level was higher in group E than group SA (P < .05). There was a significant difference in postoperative motor block, but no difference in systolic blood pressure and heart rate.

CONCLUSION

Among 3 techniques, saddle block might be preferable in HoLEP because an adequate sensorial level was achieved with lower motor block and stable hemodynamics.

Adequacy of Anesthesia and Pupillometry for Endoscopic Sinus Surgery

Inadequate intraoperative analgesia causes the deterioration of the condition of the surgical field (CSF) as a result of hemodynamic instability. Analgesia monitors are used to guide remifentanil) infusion to optimize intraoperative analgesia. The main aim of the current randomized controlled trial was to investigate the potential advantages of intraoperative analgesia monitoring using surgical Pleth index (SPI)- or pupillometry (PRD)-guided remifentanil administration for managing the volume of total intraoperative blood loss (TEIBL), CSF, and length of operation (LOP) in comparison with the standard practice in patients undergoing endoscopic sinus surgery (ESS). The 89 patients in our study were grouped as follows: 30 patients were assigned to the general analgesia (GA) group, 31 patients were assigned to the SPI group, and 28 patients were assigned to the PRD group. The speed of remifentanil infusion was accelerated by 50% when SPI, PRD, or BSS were increased by >15 points, >5%, or >2, respectively, in adjacent groups until their normalization. The SPI group showed significantly lower TEIBL in comparison to the GA group (165.2 ± 100.2 vs. 283.3 ± 193.5 mL; p < 0.05) and a higher mean arterial pressure (MAP; 73.9 ± 8 vs. 69.2 ± 6.8 mmHg; p < 0.05). In the PRD group, a shorter LOP compared with the GA group was observed (63.1 ± 26.7 min vs. 82.6 ± 33.1 min; p < 0.05). It was noted that the PRD group had a lower total remifentanil consumption than the SPI group (1.3 ± 1.4 vs. 1.8 ± 0.9 mg; p < 0.05). In ASA I-III patients undergoing ESS, intraoperative monitoring based on state entropy and SPI values can optimize the CSF and reduce TEIBL, whereas monitoring based on state entropy and PRD measurements can optimize the cost effectiveness of anesthetic drugs and the use of the operation room.

Anesthetic management of unruptured intracranial aneurysms: a qualitative systematic review

Intracranial aneurysms (IA) occur in 3-5% of the general population and may require surgical or endovascular obliteration if the patient is symptomatic or has an increased risk of rupture. These procedures carry an inherent risk of neurological complications, and the outcome can be influenced by the physiological and pharmacological effects of the administered anesthetics. Despite the critical role of anesthetic agents, however, there are no current studies to systematically assess the intraoperative anesthetic risks, benefits, and outcome effects in this population. In this systematic review of the literature, we carefully examine the existing evidence on the risks and benefits of common anesthetic agents during IA obliteration, their physiological and clinical characteristics, and effects on neurological outcome. The initial search strategy captured a total of 287 published studies. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, 28 studies were included in the final report. Our data showed that both volatile and intravenous anesthetics are commonly employed, without evidence that either is superior. Although no specific anesthetic regimens are promoted, their unique neurological, cardiovascular, and physiological properties may be critical to the outcome in vulnerable patients. In particular, patients at risk for perioperative ischemia may benefit from timely administration of anesthetic agents with neuroprotective properties and optimization of their physiological parameters. Further studies are warranted to examine if these anesthetic regimens can reduce the risk of neurological injury and improve the overall outcome in these patients.

Comparison of hypotensive properties of dexmedetomidine versus clonidine for induced hypotension during functional endoscopic sinus surgery: A randomised, double-blind interventional study

Background and Aims

Excessive bleeding is a major concern in functional endoscopic sinus surgery (FESS) under general anaesthesia; this can be decreased by various hypotensive agents. This study was conducted to compare the hypotensive effectiveness and haemodynamic stability of dexmedetomidine and clonidine in patients undergoing elective FESS.

Methods

In this prospective double-blinded interventional study, 70 adult patients of either sex, 20-50 years of age, posted for elective FESS were randomly assigned to two groups. Group A received a loading dose of intravenous (IV) dexmedetomidine 1 μg/kg, followed by infusion of 1 μg/kg/h, and group B received a loading dose of IV clonidine 2 μg/kg, followed by 1 μg/kg/h infusion. Surgical field quality, emergence time, sedation score, visual analogue score, recovery profile and haemodynamic parameters were recorded. Statistical analysis was done by Student's unpaired t-test to evaluate the significance of normally distributed variables, whereas Mann-Whitney test and Chi-square test were used for ordinal data and categorical variables and proportions, respectively.

Results

In both the groups, target mean arterial pressure (MAP) of 65-70 mmHg and improved surgical field quality were achieved. MAP and heart rate (HR) were statistically significantly lower in the dexmedetomidine group with a longer duration of post-operative analgesia (P = 0.001). None of the groups showed any statistically significant adverse effects.

Conclusions

Both dexmedetomidine and clonidine can be used for controlled hypotension to improve surgical field quality in FESS. Dexmedetomidine provides more haemodynamic stability and an additional benefit of post-operative analgesia and conscious sedation.

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.

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.

Preoperative Ultrasound-Guided Trigeminal Nerve Block in Orthognathic Surgery: A Prospective Study About Its Efficacy of Intraoperative Anesthetic Dosage and Postoperative Analgesia

PURPOSE

Ultrasound-guided trigeminal nerve block is rarely used in orthognathic surgery, and its impact of postoperative analgesia and the auxiliary effect on hypotensive anesthesia have not been fully reported. The purpose of this study is to measure the efficacy of ultrasound-guided trigeminal nerve block on intraoperative anesthetic dosage and postoperative analgesia.

PATIENTS AND METHODS

In this single-blind, prospective, controlled trial, all patients were randomly assigned to 2 groups (n = 21/group): GEA group (general anesthesia) and TNB group (ultrasound-guided trigeminal nerve block [UGTNB] with general anesthesia). The primary variable was postoperative pain (visual analog scale scores, VAS scores) at postoperative 2, 4, 6, 12, and 24 hours. Satisfaction with postoperative pain management during postoperative 24 hours; the number of patients with moderate-to-severe pain (VAS score: >3) at postoperative 2, 4, 6, 12, 24 hours; and the consumption of opioids and nicardipine intraoperatively, etc. were secondary variables. Data were analyzed using the unpaired t, χ2, and Wilcoxon nonparametric tests.

RESULTS

In this study, 40 patients at the Peking University School and Hospital of Stomatology between January 2019 to March 2019 were included with a mean age of 24.13 ± 5.07 for statistical analysis and 37.5% were male. Compared to GEA group, the TNB group had a significantly lower VAS scores at postoperative 6 hours and 12 hours, which were 2[0,2] and 0[0,2], respectively. Furthermore, patients in TNB group were more satisfied with pain management at postoperative 24 hours than patients in GEA group (5[4,5] vs 4[3,5]; P = .03). Statistically less amount of opioids and nicardipine in TNB group were used intraoperatively (P < .01).

CONCLUSION

UGTNB use in orthognathic surgery may improve analgesia in the 24 hours after the operation, additionally, facilitate hypotensive anesthesia with fewer agents and fewer adverse effects postoperatively.

Preventive Analgesia, Hemodynamic Stability, and Pain in Vitreoretinal Surgery

Background and Objectives: Although vitreoretinal surgery (VRS) is most commonly performed under regional anaesthesia (RA), in patients who might be unable to cooperate during prolonged procedures, general anaesthesia (GA) with intraprocedural use of opioid analgesics (OA) might be worth considering. It seems that the surgical pleth index (SPI) can be used to optimise the intraprocedural titration of OA, which improves haemodynamic stability. Preventive analgesia (PA) is combined with GA to minimise intraprocedural OA administration. Materials and Methods: We evaluated the benefit of PA combined with GA using SPI-guided fentanyl (FNT) administration on the incidences of PIPP (postprocedural intolerable pain perception) and haemodynamic instability in patients undergoing VRS (p < 0.05). We randomly assigned 176 patients undergoing VRS to receive GA with SPI-guided FNT administration alone (GA group) or with preventive topical 2% proparacaine (topical anaesthesia (TA) group), a preprocedural peribulbar block (PBB) using 0.5% bupivacaine with 2% lidocaine (PBB group), or a preprocedural intravenous infusion of 1.0 g of metamizole (M group) or 1.0 g of paracetamol (P group). Results: Preventive PBB reduced the intraprocedural FNT requirement without influencing periprocedural outcomes (p < 0.05). Intraprocedural SPI-guided FNT administration during GA resulted in PIPP in 13.5% of patients undergoing VRS and blunted the periprocedural effects of preventive intravenous and regional analgesia with respect to PIPP and haemodynamic instability. Conclusions: SPI-guided FNT administration during GA eliminated the benefits of preventive analgesia in the PBB, TA, M, and P groups following VRS.

The Effect of Dexmedetomidine and Esmolol on Early Postoperative Cognitive Dysfunction After Middle Ear Surgery Under Hypotensive Technique: A Comparative, Randomized, Double-blind Study

OBJECTIVES

Postoperative cognitive dysfunction (POCD) is multifactorial, which may be caused by anesthetic and surgical causes or cerebral injury. This study aimed to evaluate the effect of dexmedetomidine as a neuroprotective drug compared to esmolol on the prevalence of POCD in adult patients undergoing middle ear surgeries under hypotensive anesthesia.

METHODS

This study included male and female adult patients, according to American Society of Anesthesiology physical status (ASA) I, the patients who underwent middle ear surgeries under hypotensive anesthesia were randomly assigned to two groups that received esmolol and dexmedetomidine. The demographic data, heart rate, mean arterial blood pressure, duration of the surgery, evaluation of the surgical field, and the Mini-Mental State Examination (MMSE) (preoperatively and at 1, 6 and 24 hours postoperatively) were recorded.

RESULTS

There was a significant difference between the numbers of patients who had POCD in MMSE1: 12 cases in the esmolol group (41.37%) compared to three cases in the dexmedetomidine group (10.34%) (P = 0.016), in MMSE6: 10 cases in the esmolol group (34.48%) compared with two cases in the dexmedetomidine group (6.89%) (P = 0.023) and in MMSE24: seven cases in the esmolol group (24.13%) compared with one case in the dexmedetomidine group (3.44%) (P = 0.022), while the median and range of MMSE score were comparable between the two groups (P > 0.05).

CONCLUSIONS

This study suggests that intraoperative use of dexmedetomidine as an adjuvant to hypotensive anesthesia reduces the incidence of POCD compared to esmolol.

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 milrinone on cerebral perfusion and postoperative cognitive function in spine surgery: Secondary analysis of a CONSORT-compliant randomized controlled trial

OBJECTIVE

To compare the effects of milrinone, sodium nitroprusside (SNP), and nitroglycerin (NTG) on induced hypotension, cerebral perfusion, and postoperative cognitive function in elderly patients undergoing spine surgery.

METHODS

Sixty patients >60 years scheduled for lumbar fusion surgery were assigned to receive milrinone (group M), SNP (group S), or NTG (group N). The administration of the study drug was initiated immediately after perivertebral muscle retraction and was stopped after completion of interbody fusion. Target blood pressure was a decrease of 30% in systolic blood pressure from baseline or mean blood pressure of 60 to 65 mm Hg. The regional cerebral venous oxygen saturation (rSVO2), as a measure of cerebral perfusion, and the change in perioperative Mini-Mental State Examination (MMSE) score, as a measure of postoperative cognitive function, were assessed.

RESULTS

During the administration of the study drug, the overall and lowest intraoperative rSVO2 values were significantly higher (P = .01 and P = .01, respectively), and the duration of rSVO2 <60% was shorter in group M than in the other groups (P = .03). In group M, intraoperative rSVO2 was not different from the basal value, whereas in groups S and N, rSVO2 was significantly lower than the basal value during the administration of the study drug, but then returned to the basal value after terminating the study drug. Basal MMSE scores were comparable among the 3 groups. The MMSE score on postoperative day 5 was higher in group M than the other groups.

CONCLUSIONS

Milrinone used to induce hypotension resulted in better intraoperative cerebral perfusion and postoperative cognitive function compared to SNP and nitroglycerin.

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.

Tourniquet use in routine primary total knee arthroplasty is associated with a higher transfusion rate and longer postoperative length of stay: a real-world study

BACKGROUND

In an enhanced recovery after surgery program, a growing number of orthopedists are reconsidering the necessity of tourniquet use in total knee arthroplasty (TKA). However, the impact of tourniquet use on transfusion rate and postoperative length of stay (PLOS) in TKA remains controversial. Therefore, we carried out a study to investigate the effect of tourniquet application in routine primary TKA on transfusion rate and PLOS.

METHODS

We analyzed data from 6325 patients who underwent primary unilateral TKA and divided them into two groups according to whether a tourniquet was applied during the procedure, and a tourniquet was used in 4902 and not used in 1423. The information for transfusion and PLOS was extracted from patients' electronic health records, and the data were analyzed with logistic and linear regression analyses.

RESULTS

Following TKA, the transfusion rate and PLOS were 14.52% and 7.72 ± 3.54 days, respectively, in the tourniquet group, and 6.47% and 6.44 ± 3.48 days, respectively, in the no-tourniquet group. After adjusting for the different related variables, tourniquet use was significantly correlated with a higher transfusion rate (risk ratio = 1.888, 95% confidence interval (CI) 1.449-2.461, P < 0.001) and a longer PLOS (partial regression coefficient (B) = 0.923, 95%CI 0.690-1.156, P < 0.001).

CONCLUSIONS

Our findings suggested that tourniquet use in routine primary TKA was related to a higher transfusion rate and a longer PLOS. The impact of tourniquet use on transfusion rate and PLOS should be taken into account in clinical practice.

Strategies for 'bloodless' surgery: the experience of cytoreductive surgery for peritoneal carcinomatosis in Jehovah's Witnesses

BACKGROUND

Cytoreductive surgery (CRS) for the management of peritoneal carcinomatosis (PC) can involve significant blood loss which necessitates the transfusion of blood products. This poses a particular challenge in the Jehovah's Witnesses population whose beliefs do not permit the transfusion of blood products or blood-related derivatives. This report describes the experience of one institution performing CRS with hyperthermic intraperitoneal chemotherapy (HIPEC) for PC in Jehovah's Witnesses and perioperative management strategies employed to avoid blood transfusion.

METHODS

A review of literature and prospectively collated data of Jehovah's Witnesses patients who underwent extensive CRS for PC and HIPEC for PC.

RESULTS

Four patients had CRS and HIPEC for PC. The median PC index score was 11 and complete cytoreduction was achieved in all cases. Primary tumours were ovarian (n = 1), colorectal (n = 2) and neuroendocrine tumour of gastrointestinal origin (n = 1). The median difference between preoperative and postoperative haemoglobin was 38 g/L (23-43 g/L). Strategies included acute normovolumaeic haemodilution and autotransfusion within a closed circuit, autotransfusion from cell salvage and provisions for possible use of a haemoglobin based oxygen carrier. Ancillary measures identified and implemented to minimize transfusion dependence included, but were not limited to, preoperative iron infusion, perioperative acute haemodilution and cell salvage, administration of tranexamic acid, prothrombinex and use of paediatric tubes for venepuncture.

CONCLUSION

The review suggests CRS and HIPEC for extensive PC can be done safely in circumstances where transfusion of allogenic blood products is not permitted.

Surgical Field Visualization during Functional Endoscopic Sinus Surgery: Comparison of Propofol- vs Desflurane-Based Anesthesia

OBJECTIVE

To assess if the type of general anesthetic affects bleeding and field visualization during endoscopic sinus surgery.

STUDY DESIGN

Prospective, randomized, controlled trial.

SETTING

Academic teaching hospital and Veterans Affairs hospital in the United States.

SUBJECTS AND METHODS

Seventy patients were randomized to 1 of 3 anesthetic regimens: (1) the volatile anesthetic desflurane (n = 22), (2) intravenous anesthesia with propofol (n = 25), or (3) a combination of propofol and desflurane (n = 23). Intravenous remifentanil was titrated to decrease the mean arterial pressure to 60 to 70 mm Hg but not ≥30% from baseline. Surgical bleeding scores were recorded along with bleeding rates and hemodynamic parameters, including cardiac output and systemic vascular resistance through pulse contour analysis from a radial arterial line. Statistics: multiple comparison tests and regression analyses; α = .05.

RESULTS

There were no differences in bleeding rate (median, 0.58, 0.85, 0.57 mL min^-1), bleeding score (2.1, 2.0, 2.0), surgery duration (79, 81, 86 minutes), extubation time (9, 7, 8 minutes), recovery room time (65, 61, 61 minutes), or any hemodynamic parameters among groups 1 through 3, respectively. Group 1 required lower remifentanil infusions than group 2 (0.11 vs 0.26 µg kg^-1 min^-1; P = .01). The bleeding score correlated positively with height (P = .014) and the Lund-MacKay score (P = .013). Bilateral vs unilateral surgery led to longer surgery duration (P = .001) and recovery room time (P = .004).

CONCLUSION

When remifentanil is used for controlled hypotension, propofol has no advantage over desflurane to improve surgical field visualization during functional endoscopic sinus surgery.