Article Summary
1. Why is this topic important? Alcohol
Alcohol is a common drug of abuse among adolescents and young adults. It is estimated that at least 50% of adolescents 12–20 years old have imbibed alcohol during any 30-d period (1). This population also accounts for nearly 20% of all the alcohol consumed in the United States (US) (1). In 2008, the rate of Emergency Department visits related to alcohol alone was 220.7 per 100,000 children age 12–17 years and 596.3 per 100,000 young adults aged 18–20 years (2).
Alcohol is one of the most commonly abused drugs that can induce respiratory failure (3). Respiratory failure from central nervous system depression is a rare but serious consequence of alcohol intoxication. In adults, this has been known to occur in a dose-dependent fashion, as ethanol affects the respiratory center in the medulla oblongata (3). However, the effects of alcohol may be greater in children as compared with adults because children are unlikely to be tolerant to its effects (4).
Signs and symptoms of respiratory depression and impending respiratory failure due to alcohol intoxication can be subtle. Hypoventilation can occur due to changes in either respiratory rate or tidal volume. Bradypneic hypoventilation is due to a decline in respiratory rate and can only be detected by continuous monitoring either via plethysmography or capnography. Hypopneic hypoventilation, which is due to a decrease in tidal volume and concomitant increase in dead space ventilation, cannot be detected with standard monitoring devices and may be difficult to detect on clinical examination as well (5). Pulse oximetry is a continuous monitor of oxygenation, however, it does not adequately assess ventilation. Among patients with apnea, the most extreme form of hypoventilation, pulse oximetry may not begin to decline for several minutes—an unacceptable delay that will be lengthier in patients who are hypoventilating 6, 7, 8.
While the management of acutely intoxicated patients centers around monitoring and supportive care, it is unclear whether standard monitoring devices such as pulse oximetry are sufficiently sensitive in detecting respiratory depression. Capnography, or end-tidal carbon dioxide (ETCO2) monitoring, is a continuous and objective way to monitor ventilation. This monitor can alert a provider within one breath to an airway or respiratory problem, thus demonstrating its superiority as a measure of ventilation (9). Many studies have shown the benefits of this device in the early detection of apnea and hypoventilation 10, 11, 12.
The primary objective of this study was to determine the frequency of hypoventilation as measured by capnography in adolescents and young adults with acute alcohol intoxication. Our secondary goal was to determine if an association existed between alcohol level and the incidence of hypoventilation. We hypothesized that hypoventilation would be detected more frequently by capnography compared with standard respiratory monitoring in adolescents and young adults who were acutely intoxicated. This would provide evidence for the value of continuous capnography monitoring in acutely intoxicated patients. We also hypothesized that subjects who developed hypoventilation would have higher alcohol levels than those who maintained normal ventilatory patterns.
Between September 2007 and December 2010, a convenience sample of subjects with acute alcohol intoxication was enrolled in a prospective observational pilot study. The Human Investigations Committee approved this study with a waiver of consent. This study took place in the Pediatric Emergency Department of an urban tertiary care hospital. The Pediatric Emergency Department sees approximately 32,000 patients each year.
Subjects were eligible for enrollment if they were between the ages of 14 and
Seventy-one subjects were enrolled and 65 subjects were included in the data analysis. Reasons for exclusion included lack of documentation of alcohol intoxication (n = 4) and alcohol level not indicative of intoxication (n = 2). No subjects removed the nasal-oral cannula because of discomfort or combativeness. Demographic information for the study subjects is presented in Table 1. There were a total of 283 recordings on the subject population, with a median of 4 recordings for each subject
This study demonstrated a high frequency of hypoventilation in adolescents and young adults who were acutely intoxicated with alcohol. These episodes were difficult to predict, occurring in similar proportions over the first several hours of intoxication. Furthermore, there was no correlation between initial alcohol level and risk of hypoventilation.
The number of children with acute intoxication has been on the rise 17, 18, 19. Approximately 25% of US high school students report binge drinking,
Hypoventilation, as measured by capnography, occurs frequently in adolescents and young adults who are acutely intoxicated with alcohol, is independent of initial alcohol level and is a risk factor for hypoxemia. These episodes do not steadily decrease over time, but occur in similar proportions throughout the first several hours of intoxication. Capnography should be considered as an additional monitoring device for these patients until their alcohol levels have returned to normal. 1. Why is this topic important? AlcoholArticle Summary
Respiratory arrest is crucial to the pathophysiology of fatal alcohol poisoning (Lignian et al., 1983; Adinoff et al., 1988; Vale, 2007; Wang et al., 2019). Alcohol suppresses breathing under normal conditions (Wilson and Saukkonen, 2004; Langhan, 2013) and in response to hypoxia and hypercapnia (Sahn et al., 1975; Michiels et al., 1983; McCauley et al., 1988). Identifying the mechanisms of alcohol-induced respiratory suppression may lead to better treatment strategies for alcohol poisoning.
Although the mean of RR was slightly higher than that of BrRR, the difference was not relevant. This suggests that a wireless stethoscope is as accurate as capnography, which is highly reliable,11-14 and can be used in orally respiring patients. The pharyngeal reflex is suppressed during IVS.
Cardiovascular effects may also occur: tachycardia, peripheral vasodilation, and volume depletion, which may contribute to the induction of hypothermia and hypotension.11 In young individuals, alcohol intoxication tends to be more severe than in adults, as they usually do not show tolerance to the effects developed by repeated exposures.13 Adolescents present a higher probability of intentional intoxication, especially in a pattern known as heavy episodic drinking (binge drinking), which consists in the intake of large amounts in a short period of time.
An etco2 level greater than or equal to 50 mm Hg or an absolute change from baseline greater than 10 mm Hg has been proposed to predict significant ventilatory depression in this setting.16 Because drug classes used for sedation are very often similar to those encountered in the case of drug self-poisoning,4 authors have suggested that noninvasive capnometry could help in the monitoring of drug self-poisoning patients.22,23 The goal of this study was to assess the predictive value of an etco2 level greater than or equal to 50 mm Hg for the occurrence of early complications after drug self-poisoning.
The pH-Sensor shows high sensitivity and precision, as it is functional within the entire physiologic pH range and significantly induced at pH below 7.35, which marks the transition between normal and pathologic blood pH at the onset of DKA (Kitabchi et al., 2009). Pathologic blood pH is neither reached by moderate alcohol consumption (devoid of alcoholic ketoacidosis) (Langhan, 2013) nor by intense physical exercise (devoid of lactic acidosis) (Kłapcińska et al., 2013; Wasserman et al., 2014). Thus, assuming a normal lifestyle, the pH-Sensor should be activated only during DKA.
Financial Disclosure: Equipment on loan and donated from Nellcor Puritan Bennett LLC.
Conflict of Interest: Melissa Langhan received an honorarium from Oridion for serving on an expert panel after the completion of this study and manuscript.