Age-related Differences in Propofol Dosing for Procedural Sedation in the Emergency Department

The effect of age on the induction dose of propofol for general anesthesia in dogs

OBJECTIVE

In people, the dose of propofol (DOP) required for procedural sedation and anesthesia decreases significantly with age. The objective of this study was to determine if the DOP required to perform endotracheal intubation decreases with age in dogs.

STUDY DESIGN

Retrospective case series.

ANIMALS

1397 dogs.

METHODS

Data from dogs anesthetized at referral center (2017-2020) were analyzed with three multivariate linear regression models with backward elimination using a combination of either absolute age, physiologic age, or life expectancy (ratio between age at the time of anesthetic event and expected age of death for each breed obtained from previous literature) as well as other factors as independent variables, and DOP as the dependent variable. The DOP for each quartile of life expectancy (<25%, 25-50%, 50-75%, 75-100%, >100%) was compared using one-way ANOVA. Significance was set at alpha = 0.025.

RESULTS

Mean age was 7.2 ± 4.1 years, life expectancy 59.8 ± 33%, weight 19 ± 14 kg, and DOP 3.76 ± 1.8 mg kg-1. Among age models, only life expectancy was a predictor of DOP (-0.37 mg kg-1; P = 0.013) but of minimal clinical importance. The DOP by life age expectancy quartile was 3.9 ± 2.3, 3.8 ± 1.8, 3.6 ± 1.8, 3.7 ± 1.7, and 3.4 ± 1.6 mg kg-1, respectively (P = 0.20). Yorkshire Terrier, Chihuahua, Maltese, mixed breed dogs under 10 kg, and Shih Tzu required higher DOP. Status of neutered male, ASA E, and Boxer, Labrador and Golden Retriever breeds decreased DOP, along with certain premedication drugs.

CONCLUSIONS AND CLINICAL RELEVANCE

In contrast to what is observed in people, an age cut-off predictive of DOP does not exist. Percentage of elapsed life expectancy along with other factors such as breed, premedication drug, emergency procedure, and reproductive status significantly alter DOP. In older dogs, the dose of propofol can be adjusted based on their elapsed life expectancy.

Incidence of adverse events for procedural sedation and analgesia for cardioversion using thiopental in elderly patients: a multicenter prospective observational study

Aim

The incidence and characteristics of thiopental-related adverse events (AEs) in elderly patients during procedural sedation and analgesia (PSA) have not been well studied. We aimed to characterize thiopental-related AE in elderly patients during PSA and compare the incidence of AE in elderly patients with non-elderly adults.

Methods

This is a secondary analysis of the Japanese Procedural Sedation and Analgesia Registry (JPSTAR). We included all adult patients who received thiopental for PSA in the emergency departments and excluded patients who received concomitant sedative(s) in addition to thiopental or patients with missing body weight data. We compared the incidence of AE between the non-elderly (18-64 years) and elderly groups (≥65 years).

Results

The JPSTAR had data on 379 patients who received thiopental for PSA and included 311 patients for analysis. Most (222/311, 71.3%) were elderly. Cardioversion was the most common reason for PSA (96.1%). The AE incidence between groups overall was similar, however, hypoxia was significantly more frequent in the elderly compared with the non-elderly group (10.3% versus 2.2%; adjusted odds 5.63, 95% confidence interval 1.27-25.0). The initial and total doses of thiopental were significantly lower in the elderly group than in the non-elderly group (1.95 mg/kg versus 2.21 mg/kg and 2.33 mg/kg versus 2.93 mg/kg, respectively).

Conclusions

Although elderly patients received lower doses of thiopental, hypoxic events were significantly more frequent in this group compared with the non-elderly patients. However, the AE incidence was similar.

The Influence of Age on Propofol Dosing Requirements During Procedural Sedation in the Emergency Department

Propofol is a frequently used agent for procedural sedation in the emergency department (ED). Some have suggested that propofol dosing in this setting should be adjusted in elderly patients; however, limited data exist supporting this recommendation. Additional factors that may contribute to altered propofol dose requirements in this setting have not been thoroughly explored. The objective of this analysis was to ascertain the effect age may have on the propofol dose required during procedural sedation in the ED. This retrospective study was conducted at a Level 1 academic medical center ED and included patients 18 years or older who received propofol for procedural sedation from 2015 to 2017. Those patients who were 18-64 years of age were compared with those 65 years or older. Between the two groups, total and weight-based propofol requirements for sedation, opioid doses, and adverse events were compared. This analysis included 101 procedural sedations. The median induction dose and opioid requirements before or during the procedure were not significantly different between the two groups. Compared with patients 18-64 years of age, those 65 years or older had significantly less total weight-based propofol requirements (p = 0.024) and required less total propofol for sedation (p = 0.007). In addition, patients 65 years or older required fewer repeat doses of propofol during the procedure than younger patients (p = 0.043). The incidence of adverse effects, including respiratory suppression, was not significantly different between the two groups. Patients 65 years or older may have lower weight-based propofol dosing requirements than younger patients. Utilizing a reduced total dose and repeat dosing strategy for propofol in this setting may be indicated. Further investigations are recommended to clarify factors that signal the need for more tailored dosing.

Sedation - Effects of disorders of abuse on therapeutic efficacy (SEDATE): A retrospective cohort study

BACKGROUND

The impact of alcohol or opioid use disorders on medication dosing for procedural sedation in the emergency department (ED) is unclear, as most of the literature is from gastrointestinal endoscopy. Exploring how these patient factors affect sedative and analgesic medications may inform more nuanced sedation strategies in the emergency department.

METHODS

This was a retrospective chart-review cohort study across five EDs from 2015 to 2020. Included were adult patients who underwent procedural sedation in the ED, categorized into three a priori groups: alcohol use disorder (AUD), opioid use disorder (OUD), and individuals with neither (non-SUD). Wilcoxon test was used to compare the time-averaged dose of agents between groups. Logistic regression was used to model multi-agent sedations. The propofol time-averaged dose was the primary outcome. Secondary outcomes included other agents, sedation duration, and switching to other agents.

RESULTS

2725 sedations were included in the analysis. 59 patients had a history of AUD, and 40 had a history of OUD. Time-averaged doses of medications did not differ significantly between AUD and non-SUD patients. Likewise, patients with OUD did not receive different doses of medications compared to non-SUD. The propofol doses for non-SUD, AUD, and OUD were 0.033 IQR 0.04; 0.042 IQR 0.05; and 0.058 IQR 0.04 mg/kg*min, respectively. Sedation duration was not different across groups. Having AUD or OUD is not associated with increased odds of requiring multiple sedative agents.

CONCLUSION

Although sedation in patients with AUD or OUD may be associated with significant case bias, these patient factors did not significantly alter outcomes compared to the general population. This study suggests there is no evidence to proactively adjust medication strategy in ED patients with AUD or OUD.

Pediatric characteristics and the dose of propofol for sedation during radiological examinations: a retrospective analysis

OBJECTIVE

The present study aimed to investigate patients' characteristics that can affect the dose of propofol required to sedate children undergoing imaging.

METHODS

In this retrospective, observational study, we reviewed medical records of children aged 0 to 18 years who were classified as having American Society of Anesthesiologists status 1 or 2 and they underwent imaging under propofol sedation between January 2011 and August 2016. Collected data included patients' demographics, propofol doses, duration of sedation, and complications. Regression analysis was performed to determine patients' characteristics that may affect the dose of propofol required to induce sedation.

RESULTS

A total of 925 patients were included. Simple linear regression showed that the dose of propofol was correlated with age, height, weight, and body surface area. Using the results of multiple linear regression, the following formula was used to estimate the dose of propofol (mg) for sedation: 0.75 + 0.14 × age (months) + 45.82 × body surface area (m²).

CONCLUSION

A child's age, height, and body surface area should be considered when deciding the induction dose of propofol. Additionally, the formula that we have proposed can be used to estimate the dose of propofol required to induce sedation in children undergoing imaging.

Brain Aging and Anesthesia

Herein, the authors review the neuroanatomical and the neurophysiological aspects of the normal aging evolution based on the recent literature and briefly describe the difference between physiological and pathological brain aging, with consideration of the currently recommended anesthesia management of older patients. The population of elderly patients is growing drastically with advances in medicine that have prolonged the life span. One of the direct consequence has been a significant increase in the request for anesthesia care for older patients despite the type of surgery (cardiac vs noncardiac and mainly orthopedic). Because the brain of this category of patients undergoes a specific triple influence (immune, metabolic, and inflammatory), some particular physiological, anatomical, and structural modifications must be taken into account because they expose these patients more specifically to postoperative cognitive disturbances. To prevent type of adverse outcome, a better knowledge and understanding of these neurosciences must be promoted. The strategies developed to prevent such adverse outcomes include the determination and detection of significant at-risk patients and improvement in the titration of anesthesia to reduce exposure of anesthesia to these patients through an adapted anesthesia-induced unconsciousness that avoids, as much as possible, the risk of toxic overdose with an overly deep brain depression. To accomplish this, the unprocessed electroencephalogram (EEG) and its spectrogram may represent a significant improvement in monitoring, first by allowing for the rapid recognition of repetitive or persistent EEG suppression by the on-line reading of the raw EEG trace and second by allowing for the accurate determination of the adequate anesthetic-induced state, obtained in general in this category of patients by substantially lowered doses of anesthetic agents. This represents a new methodology for anesthesia titration that is adjusted on a more case-by-case basis and is related to the physiology of individual patients. A better understanding of aging-induced brain transformations remains the key regarding the improvement of the anesthetic management of the always growing population of elderly patients. The promotion of the unprocessed EEG may represent the best method of preventing the risk of anesthetic toxicity, including postoperative cognitive dysfunctions.

Comparison in anesthetic effects of propofol among patients with different ABO blood groups

Our study was aimed to investigate anesthetic effects of propofol in patients with different blood groups.A total of 72 participants were enrolled from patients arranged for surgeries of cholecystectomy, tonsillectomy, and spinal operation. Each blood group (A, B, AB, and O) contained 18 participants. Mean arterial pressure (MAP), heart rate (HR), and bispectral index (BIS) were assayed with Philips monitor. These indexes were observed before propofol anesthesia (T0), and then were recorded when concentration of propofol was 1 μg/mL (T1), 2 μg/mL (T2), 3 μg/mL (T3), and 4 μg/mL (T4). The differences in MAP, HR, and BIS at T0 among groups were compared with the χ test. Multiple comparisons were adopted to calculate the differences in MAP, HR, and BIS between groups at T1, T2, T3, and T4.No significant differences in age, sex, and weight of all groups were found (P > .05). Before propofol anesthesia (T0), all the participants exhibited no differences in MAP, HR, and BIS (P > .05). Subsequently, we found obvious differences in ΔMAP, ΔHR, and ΔBIS between groups. The patients in the B blood group showed highest ΔMAP and ΔHR at each time point (P < .05 for both). As for ΔBIS, patients in A blood group exhibited highest value at T3 and T4 (P < .05).The blood group remarkably affects the anesthetic effects of propofol.

Acute pulmonary edema associated with propofol: an unusual complication

Propofol is frequently used in the emergency department to provide procedural sedation for patients undergoing various procedures and is considered to be safe when administered by trained personnel. Pulmonary edema after administration of propofol has rarely been reported. We report a case of a 23-year-old healthy male who developed acute cough, hemoptysis and hypoxia following administration of propofol for splinting of a foot fracture. Chest radiography showed bilateral patchy infiltrates. The patient was treated successfully with supportive care. This report emphasizes the importance of this potentially fatal propofol-associated complication and discusses possible underlying mechanisms and related literature.

SEDASYS(®), airway, oxygenation, and ventilation: anticipating and managing the challenges

In May 2013, the FDA (Federal Drug Administration) approved SEDASYS(®), a device that enables non-anesthesia physicians to provide mild-to-moderate sedation to patients undergoing colonoscopy and esophagogastroduodenoscopy. SEDASYS(®) is the first among the devices being built to provide computer-assisted personalized sedation. Although the intention of this approval is to cut the anesthesia related expenses, it is likely to create new challenges to the users-both clinical and administrative-that might even increase the cost. Deep sedation is required frequently for a successful completion of the procedure, which poses unforeseen challenges. The present review aims to provide clear information to the users regarding pre-procedure assessment, possible sedation related complications and management options.

The aging brain and anesthesia

PURPOSE OF REVIEW

To review the neurophysiology and neuroanatomy of normal aging and the recent recommendations for the clinical management of general anesthesia and sedation in the elderly.

RECENT FINDINGS

As the population ages, the number of elderly patients having surgery is likewise increasing and with it, the prevalence of postoperative cognitive disorders. Postoperative cognitive disorders including delirium and postoperative cognitive dysfunction are common postanesthesia complications in elderly patients. Several risk factors for postoperative disorders have been identified, and anesthesiologists commonly adapt their practice habits when taking care of elderly patients to try to mitigate the effects of the anesthetics on postoperative cognitive function. These practices are reasonable and prudent; yet, they are not well supported by an understanding of the aging brain and specifics of how the anesthetic effects on the brain change with age. Through functional imaging and electrophysiological studies, much is being learned about the neurophysiology and the neuroanatomy of normal aging.

SUMMARY

Our analysis suggests that understanding the neurophysiology and neuroanatomy should be part of the standard working knowledge of anesthesiologists and that this knowledge can guide their use of the electroencephalogram to track more accurately the brain states of elderly patients receiving anesthesia care.