Review of benefits and adverse effects of the most commonly used local anesthetic adjuvants in peripheral nerve blocks.

Recently, peripheral nerve blocks are extensively applied for many patients undergoing surgical or nonsurgical analgesia. However, the effectiveness is limited by the duration of action of local anesthetics. Therefore, the application of adding local anesthetic adjuvants is evolved to prolong the duration of analgesia and decrease the concentration of local anesthetics in peripheral nerve blocks. There are many local anesthetic adjuvants available such as morphine, fentanyl, sufentanil, hydromorphone, and buprenorphine, dexmedetomidine, dexamethasone, midazolam, and magnesium sulfate. Most of them are safe and possess little adverse effects, while none of them is acknowledged by the food and drug administration. Therefore, this review is aimed to delineate benefits and adverse effects for clinical anesthesia.

Patient and Caregiver Experiences With and Perceptions of Risk Evaluation and Mitigation Strategy Programs With Elements to Assure Safe Use.

Importance: The US Food and Drug Administration (FDA) Amendments Act of 2007 authorized the FDA to impose safety requirements on drugs with important risks, such as prescriber certification or routine laboratory testing, to ensure that the benefits of use outweighed the risks. However, little is known about patient and caregiver experiences with these Risk Evaluation and Mitigation Strategy (REMS) programs with Elements to Assure Safe Use (ETASU). Objective: To understand patient and caregiver experiences with and perceptions of REMS programs with ETASU. Design, Setting, and Participants: This qualitative study included semistructured qualitative phone interviews conducted between 2016 and 2017, with initial analysis performed in 2017 and reanalysis performed in 2021. Adult patients prescribed natalizumab or sodium oxybate, adult patients or caregivers of adult patients prescribed vigabatrin, and adult female patients of reproductive age prescribed riociguat were included. Main Outcomes and Measures: Assessment of knowledge, decision-making, medication access, and perceptions of medical privacy. Results: Among 63 participants, 46 (73%) were female. Twenty-five participants (40%) had taken natalizumab, 10 (16%) riociguat, 15 (24%) sodium oxybate, and 10 (16%) vigabatrin. One participant had taken both natalizumab and vigabatrin; 4 (6%) were caregivers of patients using vigabatrin. Most participants expressed knowledge of REMS program requirements, but many lacked the insight that these requirements were part of an FDA-mandated special safety program and expressed difficulty understanding program education materials. REMS requirements made some participants more likely to initiate treatment. However, many reported burdens accessing medication, including the need to travel to certified prescribers or pharmacies. Manufacturer access to personal health information was also controversial, although some participants expressed an altruistic desire to assist others. Conclusions and Relevance: This qualitative study found that REMS programs with ETASU reassured patients and their caregivers about drug safety and helped support medication initiation. However, steps are needed to improve the quality of REMS educational materials, promote efficient medication access, and protect patient privacy.

Prospective real-time evaluation of the QTc interval variation after low-dose droperidol among emergency department patients.

OBJECTIVE: To assess the QTc interval variation after low-dose droperidol in a population of undifferentiated, stable, and non-agitated patients receiving droperidol in the emergency department. METHODS: Prospective cohort study of patients aged ≥12 years of age who received low-dose droperidol (≤ 2.5 mg) for indications other than acute behavioral disturbances. QTc intervals were monitored in real-time during pre-specified observation periods in the ED. Primary outcome was variation of QTc interval after droperidol administration, defined as the maximum delta (change) of QTc interval. Other outcomes included proportion of patients with a QTc ≥ 500 ms after droperidol, delta ≥ +60 ms, and incidence of clinical adverse events. Patients were monitored up to 30 min after IV bolus and up to 46 min after infusion. RESULTS: A total of 68 patients were included (mean age 42.1 years, 66.2% females). The median dose of droperidol was 1.875 mg (range 0.625 mg, 2.5 mg) and 94.1% received droperidol for headache management. Most patients received droperidol as a 2-min bolus (n = 41, 60.3%). The mean maximum delta of QTc interval after droperidol across all 68 patients was +29.9 ms (SD 15). A total of 12 patients (17.6%) experienced a QTc interval ≥ 500 ms during the observation period after droperidol, and 3 patients (4.4%) had a delta QTc ≥ +60 ms. There were no serious arrhythmias, such as TdP, or deaths among the 68 participants in this study (0/68). However, 13.2% (n = 9) had at least one non-serious adverse event including restlessness and/or anxiety. CONCLUSION: The QTc interval slightly increased after droperidol administration, but these prolongations were brief, mostly below 500 msec and did not lead to serious arrhythmias. The yield of continuous cardiac monitoring in patients receiving low doses of droperidol is likely low.

Risk Factors for Fentanyl-Induced Cough Following General Anesthesia in Adults: A Retrospective Study from a Single Center in China.

BACKGROUND Fentanyl-induced cough (FIC) during general anesthesia induction and postoperative nausea and vomiting are common complications, yet the risk factors for FIC remain controversial. This retrospective study was conducted at a single center in China and aimed to investigate the risk factors for fentanyl-induced cough following general anesthesia in adults. MATERIAL AND METHODS A total of 601 adult patients undergoing elective surgery were enrolled, and the incidence of FIC during general anesthesia induction and postoperative adverse events were recorded. The risk factors for FIC during general anesthesia induction and postoperative nausea and vomiting were assessed using multivariate logistic regression analysis. RESULTS The incidence of FIC, nausea, and vomiting were 21.8%, 6.3%, and 4.5%, respectively. The results of multivariate logistic regression analysis indicated that pharyngitis history was associated with an increased risk of FIC during general anesthesia induction (odds ratio [OR]: 2.852; 95% confidence interval [CI]: 1.698-4.792; P<0.001), whereas use of lidocaine could protect against FIC risk (OR: 0.649; 95% CI: 0.557-0.757; P<0.001). However, the characteristics of patients were not associated with the risk of postoperative nausea and vomiting. CONCLUSIONS The findings from this study showed that a history of pharyngitis increased the risk of FIC, while the use of lidocaine was associated with a reduced risk of FIC. The risk of postoperative nausea and vomiting was not affected by fentanyl use or patient characteristics.

The Facilitatory Effects of Adjuvant Pharmaceutics to Prolong the Duration of Local Anesthetic for Peripheral Nerve Block: A Systematic Review and Network Meta-analysis.

BACKGROUND: Peripheral nerve block (PNB) with perineural local anesthetic is used for anesthesia or analgesia with many benefits. To extend these benefits, various adjuvant drugs have been used to prolong the duration of analgesia. We aimed to evaluate the effectiveness of various adjuvants at prolonging the duration of sensory and motor blockade for PNB. METHODS: A network meta-analysis of placebo-controlled and active randomized controlled trials was performed comparing 10 adjuvants. Embase, PubMed, Web of Science, and Cochrane library were searched, with articles before May 21, 2020 included. Two authors independently selected studies and extracted data. The primary outcomes were sensory block (SB) and motor block (MB) time, and the secondary outcome was time of first analgesia rescue (FAR). Effect size measures were described as mean differences (MD) with 95% confidence intervals (CIs). Confidence in evidence was assessed using Confidence in Network Meta-Analysis (CINeMA). The study protocol was preregistered with the prospectively registered systematic reviews in health and social care international database (PROSPERO), as number CRD42020187866. RESULTS: Overall 16,364 citations were identified, of which 53 studies were included with data for 3649 patients. In network meta-analyses, 4 of 7 included treatment strategies were associated with more efficacious analgesia compared with placebo therapy, including dexamethasone (SB time: 5.73 hours, 95% CI, 4.16-7.30; MB time: 4.20 hours, 95% CI, 2.51-5.89; time of FAR: 8.71 hours, 95% CI, 6.63-10.79), dexmedetomidine (SB time: 4.51 hours, 95% CI, 3.52-5.50; MB time: 4.04 hours, 95% CI, 2.98-5.11; time of FAR: 5.25 hours, 95% CI, 4.08-6.43), fentanyl (SB time: 3.59 hours, 95% CI, 0.11-7.06; MB time: 4.42 hours, 95% CI, 0.78-8.06), and clonidine (SB time: 2.75 hours, 95% CI, 1.46-4.04; MB time: 2.93 hours, 95% CI, 1.69-4.16; time of FAR: 3.35 hours, 95% CI, 1.82-4.87). In a subgroup analysis, addition of dexamethasone to ropivacaine significantly increased the time of FAR when compared to dexmedetomidine (time of FAR: 5.23 hours, 95% CI, 2.92-7.54) or clonidine (time of FAR: 6.61 hours, 95% CI, 4.29-8.92) with ropivacaine. CONCLUSIONS: These findings provide evidence for the consideration of dexmedetomidine, dexamethasone, and clonidine as adjuvants to prolong the duration of PNB. The addition of dexamethasone to ropivacaine has a longer time of FAR compared with clonidine or dexmedetomidine.

The Effects of Anesthetics and Perioperative Medications on Immune Function: A Narrative Review.

Preclinical and clinical studies have sought to better understand the effect of anesthetic agents, both volatile and intravenous, and perioperative adjuvant medications on immune function. The immune system has evolved to incorporate both innate and adaptive components, which are delicately interwoven and essential for host defense from pathogens and malignancy. This review summarizes the complex and nuanced relationship that exists between each anesthetic agent or perioperative adjuvant medication studied and innate and adaptive immune function with resultant clinical implications. The most commonly used anesthetic agents were chosen for review including volatile agents (sevoflurane, isoflurane, desflurane, and halothane), intravenous agents (propofol, ketamine, etomidate, and dexmedetomidine), and perioperative adjuvant medications (benzodiazepines, opioids, nonsteroidal anti-inflammatory drugs [NSAIDs], and local anesthetic agents). Patients who undergo surgery experience varying combinations of the aforementioned anesthetic agents and adjuncts, depending on the type of surgery and their comorbidities. Each has unique effects on immunity, which may be more or less ideal depending on the clinical situation. Further study is needed to better understand the clinical effects of these relationships so that patient-specific strategies can be developed to improve surgical outcomes.

A comparative study of propofol alone and propofol combined with midazolam for dental treatments in special needs patients.

ABSTRACT: Although dental treatment with sedation is performed increasingly in special needs patients, data on adding midazolam to intravenous propofol sedation are very limited for this group. The purpose of this study was to identify the factors and procedure time associated with the use of intravenous sedation with propofol alone or propofol combined with midazolam in dental patients with special needs.This was a retrospective data analysis. The sedation medications and relevant covariates, including demographic parameters, disability levels, oral health conditions, dental procedures, treatment time, and side effects, of 718 patients with special needs were collected between April 2013 and September 2014. The unfavorable side effects by sedation types were reported. Factors associated with procedure time and the sedation medications were assessed with multiple logistic regression analyses.Of 718 patients, 8 patients experienced unfavorable side effects (vomiting, sleepiness, or emotional disturbance) after the dental procedures; the rate was 0.6% in the 509 patients who received propofol only. In 209 patients who received propofol and midazolam, 2.4% experienced the side effects. Sedation time was associated with body mass index (BMI) < 25 (adjusted odds ratio [aOR] = 1.45, 95% confidence interval [CI]: 1.04-2.04) and the performance of multiple dental procedures (aOR = 1.44, 95% CI: 1.06-1.97) but not associated with the sedation types. A significant odds ratio for the combined use of propofol and midazolam was shown for adolescents (aOR = 2.22, 95% CI: 1.28-3.86), men (aOR = 2.05, 95% CI: 1.41-2.98), patients with cognitive impairment (aOR = 1.99, 95% CI: 1.21-3.29), and patients undergoing scaling procedures (aOR = 1.64, 95% CI: 1.13-2.39).With the acceptable side effects of the use of propofol alone and propofol combined with midazolam, multiple dental procedures increase the sedation time and the factors associated with the combined use of propofol and midazolam are younger age, male sex, recognition problems, and the type dental procedure in the dental treatment of patients with special needs.

Midazolam Premedication Immediately Before Surgery Is Not Associated With Early Postoperative Delirium.

BACKGROUND: Postoperative delirium is common among older surgical patients and may be associated with anesthetic management during the perioperative period. The aim of this study is to assess whether intravenous midazolam, a short-acting benzodiazepine used frequently as premedication, increased the incidence of postoperative delirium. METHODS: Analyses of existing data were conducted using a database created from 3 prospective studies in patients aged 65 years or older who underwent elective major noncardiac surgery. Postoperative delirium occurring on the first postoperative day was measured using the confusion assessment method. We assessed the association between the use or nonuse of premedication with midazolam and postoperative delirium using a χ2 test, using propensity scores to match up with 3 midazolam patients for each control patient who did not receive midazolam. RESULTS: A total of 1266 patients were included in this study. Intravenous midazolam was administered as premedication in 909 patients (72%), and 357 patients did not receive midazolam. Those who did and did not receive midazolam significantly differed in age, Charlson comorbidity scores, preoperative cognitive status, preoperative use of benzodiazepines, type of surgery, and year of surgery. Propensity score matching for these variables and American Society of Anesthesiology physical status scores resulted in propensity score-matched samples with 1-3 patients who used midazolam (N = 749) for each patient who did not receive midazolam (N = 357). After propensity score matching, all standardized differences in preoperative patient characteristics ranged from -0.07 to 0.06, indicating good balance on baseline variables between the 2 exposure groups. No association was found between premedication with midazolam and incident delirium on the morning of the first postoperative day in the matched dataset, with odds ratio (95% confidence interval) of 0.91 (0.65-1.29), P = .67. CONCLUSIONS: Premedication using midazolam was not associated with higher incidence of delirium on the first postoperative day in older patients undergoing major noncardiac surgery.

Local Anesthesia Thoracoscopy with versus without Midazolam: A Randomized Controlled Trial.

BACKGROUND: Medical thoracoscopy is the gold standard for the diagnosis of pleural diseases. To date, no consensus exists regarding the choice of sedative and analgesic agents in patients undergoing local anesthetic thoracoscopy (LAT), and questions are raised as to whether sedatives may add to respiratory side effects. OBJECTIVE: The aim of the study was to test the hypothesis that administration of midazolam associated with lidocaine versus lidocaine alone in patients with LAT adds to respiratory side effects. METHODS: We randomly assigned 80 patients to a 1:1 study to 2 groups: local anesthesia by lidocaine (n = 40) versus lidocaine and midazolam (n = 40), with the primary end point being the mean lowest oxygen saturation. The secondary end points were cardiovascular parameters, complications, days of drainage, hospital stay, and patients' quality of life (QoL) as assessed by a visual analog scale (VAS). RESULTS: The mean age of all patients was 66.6 ± 13.1 years. The study comprised 50 males (62.5%). No difference was observed in the demographics between the 2 groups. No significant difference was observed between the 2 groups in oxygen saturation (primary end point). A significant difference was observed in favor of the midazolam group regarding the QoL assessed by VAS. CONCLUSION: Midazolam does not add to respiratory side effects when it is used with lidocaine for LAT, while patients' QoL is actually improved in this group. Therefore, in our department, we changed our startegy in favor of the association of lidocaine and midazolam.

Transient lower cranial nerve palsies following spinal anesthesia with bupivacaine-fentanyl combination for transurethral resection of the prostate.

Spinal anesthesia is a widely used regional anesthesia for many infra-umbilical surgical procedures with proven efficacy and safety. However, although rare, some neurologic complications can occur with potentially life threatening consequences. Among them, lower cranial nerve palsies have been rarely reported in the literature. We report such a case in a 75-year-old man with transient dysphagia, dysphonia and spinal accessory nerve palsy occurring four days after spinal anesthesia for transurethral resection of the prostate. His symptoms completely resolved spontaneously within 2 weeks. The possibility of lower cranial nerve palsies should be added to the potential complications during or following spinal anesthesia with bupivacaine-fentanyl combination. Although transitional, this complication may occur few days after the procedure and need to be promptly recognized, carefully evaluated and treated by conservative measures.

Droperidol Reduces Postoperative Nausea and Vomiting and Supports the Continuation of Intravenous Patient-Controlled Analgesia with Fentanyl.

PURPOSE: To examine the impact of adding droperidol to fentanyl-based intravenous patient- controlled analgesia (IVPCA) on the discontinuation of IVPCA use due to postoperative nausea and vomiting (PONV). METHODS: Patients who underwent surgeries other than abdominal surgeries and used IVPCA between April 2014 and March 2018 were selected. Patients using IVPCA with fentanyl alone were compared to patients using droperidol added to IVPCA. Patients were allocated to one of two groups depending on the drug used for IVPCA: 1) control group, fentanyl alone; 2) droperidol group, droperidol with fentanyl. The primary endpoint was the discontinuation of IVPCA due to PONV. Secondary endpoints included PONV within 48 hours after surgery, the number of antiemetics used, pain score, and adverse effects. Propensity score matching was used to control the differences in clinical features among patients. RESULTS: Among the 793 patients initially enrolled in this study, 145 were excluded via propensity score matching; 364 of the remaining patients received IVPCA supplemented with droperidol. Propensity score matching showed that discontinuation of IVPCA due to PONV was significantly decreased in the droperidol group compared to the control group (P = 0.01). Further, compared with the control group, the droperidol group had reduced nausea up to 24 hours after surgery (P < 0.01), and the number of vomiting episodes and use of antiemetics decreased within 12 hours after surgery (P < 0.01). CONCLUSIONS: The addition of droperidol to IVPCA is associated with a decrease in PONV, as well as the improved continuation of pain treatment with fentanyl-based IVPCA, similar to IVPCA with morphine. However, it is necessary to monitor the side effects of this treatment.

Effect of Midazolam on Vestibular Signs in Two Geriatric Dogs with Vestibular Disease.

An abrupt balance impairment, including leaning, falling, and rolling, occurred after IV administration of 0.2 mg/kg midazolam as a preanesthetic medication in two geriatric dogs with a history of nystagmus and head tilt. In the second case, leaning, falling, and rolling recurred after recovery from general anesthesia but gradually ceased after IV administration of 0.01 mg/kg flumazenil. These two cases suggest that the IV administration of midazolam was responsible for the balance impairment in dogs who were suspected to have idiopathic peripheral vestibular disease.

The assessment and management of gamma hydroxybutyrate use in general practice.

BACKGROUND: Gamma hydroxybutyrate (GHB) is an illicit drug commonly used in music festival, party and 'chemsex' settings. Most people who use GHB do so occasionally, without dependent use or withdrawal symptoms. However, a minority of users experience harms including unconsciousness and respiratory collapse in overdose. Adverse interactions can also occur when GHB is used with other drugs (eg methamphetamine), necessitating assessment, management or onward referral by general practitioners. OBJECTIVE: This article describes the use of GHB, with a contemporary update on principles of assessment and management in general practice, brief intervention and harm-minimisation strategies, and indicators for referral to a specialist in dependent use. DISCUSSION: The assessment and management of individuals with GHB-related harms in general practice is supported by an awareness of the context of use, familiarity with targeted harm-minimisation advice and cognisance of markers of risk indicating onward referral to specialist addiction services when appropriate.

Evaluation of a Safety Protocol for the Management of Thirst in the Postoperative Period.

PURPOSE: To associate medications, anesthetic techniques, and clinical conditions that interfere in the time of patient approval in the safety protocol for thirst management. DESIGN: A quantitative, analytical, and longitudinal study conducted in Southern Brazil. METHODS: A nonprobabilistic sample, of 203 adult patients in the immediate postoperative period, evaluated every 15 minutes for 1 hour. FINDINGS: A general prevalence of thirst of 67.7%, and mean intensity of 6.38. Fentanyl, morphine, rocuronium, and sevoflurane increased lack of approval in the protocol within 30 minutes (P < .05). General anesthesia (P < .0001) and level of consciousness (95.4%) presented the highest nonapproval rates. CONCLUSIONS: Anesthetics and general anesthesia delayed protocol approval; however, after 30 minutes, 75.4% of patients had been approved. Level of consciousness was the main criterion of disapproval. The protocol identified crucial clinical conditions that made it impossible for the patient to receive thirst relief strategies and demonstrated that thirst can be satiated precociously with safety.

Sedation During Endoscopy in Patients with Cirrhosis: Safety and Predictors of Adverse Events.

BACKGROUND: Sedation during endoscopy in cirrhotic patients is typically via moderate sedation, most commonly using a combination of a benzodiazepine (i.e., midazolam) and narcotic (i.e., fentanyl) or with propofol using monitored anesthesia care (MAC). Here, we examined the safety of moderate sedation and MAC in patients with cirrhosis. METHODS: This retrospective cohort study of cirrhotic patients undergoing endoscopy from a large academic medical center between 2010 and 2014 examined extensive clinical data including the following: past history, physical findings, laboratory results, and procedural adverse events. Adverse events were defined a priori and included hypoxia, hypotension, bleeding, and death. RESULTS: We identified 2618 patients with cirrhosis who underwent endoscopic procedures; the mean age was 56 years, 36% were female, the mean Child-Pugh score was 9.3 (IQR: 8, 11), and Charlson Comorbidity Index score was 3.2 (IQR: 1, 4); 1157 had MAC; and 1461 had moderate sedation. There was no difference in the frequency of adverse events in MAC and moderate sedation groups, with a total of 15 adverse events (7/1157 MAC and 8/1461 moderate sedation). The most common procedure performed was esophagogastroduodenoscopy (EGD, n = 1667) and was associated with 10 adverse events. Overall, adverse events included bradycardia (1), hypoxia (7), bleeding (5), laryngospasm (1), and perforation (1). The frequency was similar for EGD, ERCP, and colonoscopy-each at a rate of 0.6%. CONCLUSIONS: Adverse events in cirrhotic patients undergoing endoscopy appeared to be similar with moderate sedation or MAC, and the frequency was the same for different types of procedures.

Effect of intravenous dexamethasone on the anaesthetic characteristics of peripheral nerve block: a double-blind, randomised controlled, dose-response volunteer study.

BACKGROUND: Intravenous dexamethasone is thought to prolong the duration of peripheral nerve block, but the dose-response relationship remains unclear. The aim of this volunteer study was to evaluate the dose-response effect of i.v. dexamethasone on the prolongation of median nerve block. METHODS: In a double-blind, randomised controlled study, 18 volunteer subjects received two median nerve blocks separated by a washout period. One block was conducted alongside an infusion of saline and the other alongside i.v. dexamethasone 2, 4, or 8 mg. The primary outcome was time to return of normal pinprick sensation. Secondary outcomes included thermal quantitative sensory testing (QST) for the time to return of cold detection threshold (CDT), warm detection threshold (WDT), cold pain threshold (CPT), heat pain threshold (HPT), area under QST curves, grip strength, and the incidence of adverse effects. RESULTS: The primary outcome, time to recovery of pinprick sensation, was similar between volunteers receiving saline or i.v. dexamethasone, regardless of dose (P=0.99). The time to recovery of QST milestones was similar between groups, although area under QST curves indicated prolongation of CDT (0 vs 8 mg, P=0.002) and WDT (0 vs 2 mg, P=0.008; 0 vs 4 mg, P=0.001; 0 vs 8 mg, P<0.001). There was no difference in motor recovery or adverse effects. CONCLUSIONS: Intravenous dexamethasone failed to significantly prolong the duration of pinprick anaesthesia regardless of dose. However, area under QST curve analysis indicated a dose-independent prolongation of CDT and WDT, the clinical significance of which is unclear. CLINICAL TRIAL REGISTRATION: NCT02864602 (clinicaltrials.gov).

Neuropatía óptica compresiva secundaria a reacción alérgica a hialuronidasa / Compressive optic neuropathy secondary to an allergic reaction to hyaluronidase

Una mujer de 58 años presentó quemosis intensa y oftalmoparesia en el ojo izquierdo 8 h después de cirugía de catarata no complicada bajo anestesia subtenoniana. Tras tratamiento corticoideo y antihistamínico, se observó recuperación de la motilidad extrínseca pero se apreciaron un edema de papila no hemorrágico y un defecto concéntrico de campo visual. El caso evolucionó a atrofia papilar con agudeza visual central preservada pero con una contracción significativa del campo visual. El estudio etiológico reveló una alergia a la hialuronidasa, usada como adyuvante a la anestesia. Esta complicación debe ser diagnosticada y tratada precozmente, puesto que el edema de los tejidos orbitarios puede dañar el nervio óptico

A 58 year-old woman presented with severe chemosis and ophthalmoparesis on her left eye 8 hours after uncomplicated cataract surgery under sub-tenon anaesthesia. Recovery of extrinsic motility was observed after corticosteroid and antihistamine treatment, but a non-haemorrhagic papillary oedema and a concentric defect of visual field were found. It progressed to papillary atrophy with preserved central vision, but with a significant visual field constriction. The aetiological study revealed an allergy to hyaluronidase that was used as adjuvant to the anaesthesia. This complication needs to be promptly diagnosed and treated, as the swelling of the orbital tissues can cause damage to the optic nerve

Compressive optic neuropathy secondary to an allergic reaction to hyaluronidase. / Neuropatía óptica compresiva secundaria a reacción alérgica a hialuronidasa.

A 58 year-old woman presented with severe chemosis and ophthalmoparesis on her left eye 8hours after uncomplicated cataract surgery under sub-tenon anaesthesia. Recovery of extrinsic motility was observed after corticosteroid and antihistamine treatment, but a non-haemorrhagic papillary oedema and a concentric defect of visual field were found. It progressed to papillary atrophy with preserved central vision, but with a significant visual field constriction. The aetiological study revealed an allergy to hyaluronidase that was used as adjuvant to the anaesthesia. This complication needs to be promptly diagnosed and treated, as the swelling of the orbital tissues can cause damage to the optic nerve.

Efficacy and Safety of Fentanyl in Combination with Midazolam in Children on Mechanical Ventilation.

BACKGROUND: To evaluate the efficacy and safety of fentanyl for sedation therapy in mechanically ventilated children. METHODS: This was a double-blind, randomized controlled trial of mechanically ventilated patients between 2 months and 18 years of age. Patients were randomly divided into two groups; the control group with midazolam alone, and the combination group with both fentanyl and midazolam. The sedation level was evaluated using the Comfort Behavior Scale (CBS), and the infusion rates were adjusted according to the difference between the measured and the target CBS score. RESULTS: Forty-four patients were recruited and randomly allocated, with 22 patients in both groups. The time ratio of cumulative hours with a difference in CBS score (measured CBS-target CBS) of ≥ 4 points (i.e., under-sedation) was lower in the combination group (median, 0.06; interquartile range [IQR], 0-0.2) than in the control group (median, 0.15; IQR, 0.04-0.29) (P < 0.001). The time ratio of cumulative hours with a difference in CBS score of ≥ 8 points (serious under-sedation) was also lower in the combination group (P < 0.001). The cumulative amount of midazolam used in the control group (0.11 mg/kg/hr; 0.07-0.14 mg/kg/hr) was greater than in the combination group (0.07 mg/kg/hr; 0.06-0.11 mg/kg/hr) (P < 0.001). Two cases of hypotension in each group were detected but coma and ileus, the major known adverse reactions to fentanyl, did not occur. CONCLUSION: Fentanyl combined with midazolam is safe and more effective than midazolam alone for sedation therapy in mechanically ventilated children. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02172014.

The Effect of Dexmedetomidine on Propofol Requirements During Anesthesia Administered by Bispectral Index-Guided Closed-Loop Anesthesia Delivery System: A Randomized Controlled Study.

BACKGROUND: Dexmedetomidine, a selective α2-adrenergic agonist currently approved for continuous intensive care unit sedation, is being widely evaluated for its role as a potential anesthetic. The closed-loop anesthesia delivery system (CLADS) is a method to automatically administer propofol total intravenous anesthesia using bi-spectral index (BIS) feedback and attain general anesthesia (GA) steady state with greater consistency. This study assessed whether dexmedetomidine is effective in further lowering the propofol requirements for total intravenous anesthesia facilitated by CLADS. METHODS: After ethics committee approval and written informed consent, 80 patients undergoing elective major laparoscopic/robotic surgery were randomly allocated to receive GA with propofol CLADS with or without the addition of dexmedetomidine. Quantitative reduction of propofol and quality of depth-of-anesthesia (primary objectives), intraoperative hemodynamics, incidence of postoperative adverse events (sedation, analgesia, nausea, and vomiting), and intraoperative awareness recall (secondary objectives) were analyzed. RESULTS: There was a statistically significant lowering of propofol requirement (by 15%) in the dexmedetomidine group for induction of anesthesia (dexmedetomidine group: mean ± standard deviation 0.91 ± 0.26 mg/kg; nondexmedetomidine group: 1.07 ± 0.23 mg/kg, mean difference: 0.163, 95% CI, 0.04-0.28; P = .01) and maintenance of GA (dexmedetomidine group: 3.25 ± 0.97 mg/kg/h; nondexmedetomidine group: 4.57 ± 1.21 mg/kg/h, mean difference: 1.32, 95% CI, 0.78-1.85; P < .001). The median performance error of BIS control, a measure of bias, was significantly lower in dexmedetomidine group (1% [-5.8%, 8%]) versus nondexmedetomidine group (8% [2%, 12%]; P = .002). No difference was found for anesthesia depth consistency parameters, including percentage of time BIS within ±10 of target (dexmedetomidine group: 79.5 [72.5, 85.3]; nondexmedetomidine group: 81 [68, 88]; P = .534), median absolute performance error (dexmedetomidine group: 12% [10%, 14%]; nondexmedetomidine group: 12% [10%, 14%]; P = .777), wobble (dexmedetomidine group: 10% [8%, 10%]; nondexmedetomidine group: 8% [6%, 10%]; P = .080), and global score (dexmedetomidine group: 25.2 [23.1, 35.8]; nondexmedetomidine group: 24.7 [20, 38.1]; P = .387). Similarly, there was no difference between the groups for percentage of time intraoperative heart rate and mean arterial pressure remained within 20% of baseline. However, addition of dexmedetomidine to CLADS propofol increased the incidence of significant bradycardia (dexmedetomidine group: 14 [41.1%]; nondexmedetomidine group: 3 [9.1%]; P = .004), hypotension (dexmedetomidine group: 9 [26.5%]; nondexmedetomidine group: 2 [6.1%]; P = .045), and early postoperative sedation. CONCLUSIONS: The addition of dexmedetomidine to propofol administered by CLADS was associated with a consistent depth of anesthesia along with a significant decrease in propofol requirements, albeit with an incidence of hemodynamic depression and early postoperative sedation.