Acute Alcohol Intoxication in Adolescents: Frequency of Respiratory Depression

Background

Adolescents and young adults are frequent users of alcohol. Younger patients may be more sensitive to the effects of alcohol than their adult counterparts, and toxicity has been known to occur at lower doses. Respiratory depression is a serious adverse effect of alcohol intoxication; however, current monitoring practices may not adequately detect respiratory depression.

Objective

Our objective was to determine the frequency of hypoventilation as measured by capnography among adolescents with acute alcohol intoxication. Our secondary objective was to determine if an association exists between alcohol levels and incidence of hypoventilation.

Methods

This was a prospective observational pilot study of patients 14–20 years of age with acute alcohol intoxication. Blood or breath alcohol measurements were obtained on arrival. Hourly measurements of vital signs including capnography were recorded.

Results

Sixty-five subjects were analyzed. Mean alcohol level was 185 mg/dL. Twenty-eight percent of subjects had episodes of hypoventilation. Episodes occurred in similar proportions on arrival and during the first 5 h of measurements. There was no difference in alcohol levels between subjects who did and did not hypoventilate (185 mg/dL vs. 186 mg/dL; 95% confidence interval −29 to 25). Oxygen desaturations occurred in 14 subjects and were associated with hypoventilation (p = 0.015).

Conclusions

Hypoventilation is common among adolescents who are acutely intoxicated with alcohol. It is independent of alcohol level and occurs at a steady rate during the first several hours of intoxication. Capnography should be considered as an additional monitoring device to detect these episodes and enhance patient safety.     

Investigating the Effects of Protective Face Masks on the Respiratory Parameters of Children in the Postanesthesia Care Unit During the COVID-19 Pandemic

PurposeThe purpose of this study was to investigate the effect of protective face mask usage during the postoperative period on carbon dioxide retention in children during the COVID-19 pandemic.DesignThis study was designed as a prospective, randomized trial including 40 ASA I–II patients aged 3 to 10 years who were scheduled for elective surgery.MethodsPatients were randomly allocated to two groups. The first group (group 1) received O₂ treatment over the protective face mask. In the second group (group 2), the protective face mask was worn over the O₂ delivery system. Heart rate, oxygen saturation (SPO₂) level, end-tidal carbon dioxide (EtCO₂) level, and respiratory rate were measured using a patient monitor at 0, 5, 10, 15, 30, and 45 minutes and recorded. The primary outcome of the study was the determination of the EtCO₂ levels, which were used to assess the safety of the mask in terms of potential carbon dioxide retention.FindingsNone of the participants’ SPO₂ levels fell below 92% while wearing masks. There was no statistically significant difference between the groups in terms of EtCO₂, heart rate, SPO₂, and respiratory rate (P > .05).ConclusionsDuring the COVID-19 pandemic, protective surgical face masks can be used safely in the postoperative period for pediatric patients aged 3 to 10 years.     

A Sudden Increase in Partial Pressure End-Tidal Carbon Dioxide (PETCO2) at the Moment of Return of Spontaneous Circulation

Background: Previous studies established that a level of partial pressure end-tidal carbon dioxide (P_ETCO₂) of 10 mm Hg divided patients undergoing advanced life support (ALS) into those likely to be resuscitated (values > 10 mm Hg) and those likely to die during ALS (values < 10 mm Hg). Objective: The study tested the significance of a sudden increase in the P_ETCO₂ in signaling the return of spontaneous circulation (ROSC) during ALS. Material and Methods: P_ETCO₂ values were continuously recorded during ALS in out-of-hospital patients with cardiac arrest. Constant ventilation was maintained by an automatic device. There were 108 patients, representing two extreme outcomes of ALS, who were subdivided into two groups. The first group included 59 patients with a single ROSC followed by a stable spontaneous circulation. The second group included 49 patients with no signs of ROSC. Results: ROSC was associated with a sudden increase in P_ETCO₂ that remained significantly higher than before ROSC. P_ETCO₂ did not rise during the entire ALS in the second group of patients without ROSC and was lower than in the first group of patients. Conclusions: In constantly ventilated patients, P_ETCO₂ is significantly higher (about 10 mm Hg) after ROSC than before ROSC. A sudden increase in P_ETCO₂ exceeding 10 mm Hg may indicate ROSC. Consequently, the rule of 10 mm Hg may be extended to include a sudden increase in continuously recorded P_ETCO₂ by more than 10 mm Hg as an indicator of the possibility of ROSC.     

容积二氧化碳图在特发性肺纤维化患者中的改变

容积二氧化碳图(VCap)是一种属于气体交换范畴的肺功能检查,其以呼出气的二氧化碳(CO2)分压或体积分数为纵轴,呼出气容积为横轴,体现呼气过程中CO2水平随呼出气体积增加的变化。作为一种新的检测技术,VCap具有便捷的优势,在国外已为许多临床领域所接受,但国内尚处于起     

Capnometry for continuous postoperative monitoring of nonintubated,spontaneously breathing patients

We continuously monitored spontaneous respiration after extubation by end-tidal CO₂ tension (PetCO₂) in 19 patients aged 20 to 72 years who had undergone major operations. The respiratory gas was sampled from the nasopharynx via a special nasal catheter and analyzed by a side-stream analyzer. In each case, optimal placement of the nasal catheter was determined by CO₂ waveform and the capnograms were recorded for waveform analysis and trend monitoring.PetCO₂ was compared with arterial CO₂ tension (PaCO₂) two to four times during the 2- to 19-hour observation periods by simultaneous measurements. For 65 simultaneous measurements, meanPetCO₂ was 38.9 ± 5.7 mm Hg (range, 26.3 to 48.3 mm Hg) and mean PaCO₂ was 38.9 ± 5.7 mm Hg (range, 26.8 to 46.0 mm Hg;r=0.82;p<0.01). While the mean values forPetCO₂ and PaCO₂ were similar, several patients had large differences for PaCO₂ toPetCO₂. The differences of the individual patients did not differ significantly between the various times of measurement. We conclude that this form of capnometry is well suited for continuous, noninvasive monitoring of respiration in nonintubated, spontaneously breathing patients.     

Accurate determination of end-tidal carbon dioxide during administration of oxygen by nasal cannulae

Measurement of end-tidal carbon dioxide tension (PetCO₂) by mass spectrometry or infrared capnometry provides a clinically useful approximation of arterial carbon dioxide tension (PaCO₂) in intubated patients. Although several devices have been proposed to samplePetCO₂ during spontaneous breathing (i.e., unintubated patients receiving supplemental oxygen), thus far no reports have documented their efficacy. This article reports the use of an easily constructed modification of simple nasal cannulae that permits accurate sampling ofPetCO₂ during oxygen administration to unintubated patients. After amputation of the closed tip, a cap from a syringe was inserted via a slit made at the base into one prong of a pair of nasal cannulae. A capnometer was connected to the syringe cap, andPetCO₂ and PaCO₂ were determined simultaneously during the administration of 3 L/min oxygen via nasal cannulae to 21 normocapnic patients. The PaCO₂ —PetCO₂ gradients were calculated and compared with values obtained in the same patients after intubation and mechanical ventilation. No significant difference was found between the calculated gradients with nasal cannulae (2.09±2.18 mm Hg) versus intubation (2.87±2.82 mm Hg). Simultaneous oxygen administration and accurate sampling ofPetCO₂ may be achieved in unintubated patients by using this easily constructed modification of nasal cannulae.Supported in part by PPG Biomedical Systems, Lenexa, KS.The apparatus and method described herein are covered by U.S. Patent Application S.N. 181,814: Method and Apparatus for Inhalation of Treating Gas for Quantitative Analysis. Filed April 15, 1988—in the name of Edwin A. Bowe, et al.     

Oxygenator exhaust capnography for prediction of arterial carbon dioxide tension during hypothermic cardiopulmonary bypass

Continuous monitoring and control of arterial carbon dioxide tension (P(a)CO2) during cardiopulmonary bypass (CPB) is essential. A reliable, accurate, and inexpensive system is not currently available. This study was undertaken to assess whether the continuous monitoring of oxygenator exhaust carbon dioxide tension (PexCO2) can be used to reflect P(a)CO2 during CPB. A total of 33 patients undergoing CPB for cardiac surgery were included in the study. During normothermia (37 degrees C) and stable hypothermia (31 degrees C), the values of PexCO2 from the oxygenator exhaust outlet were monitored and compared simultaneously with the P(a)CO2 values. Regression and agreement analysis were performed between PexCO2 and temperature corrected-P(a)CO2 and temperature uncorrected-P(a)CO2. At normothermia, a significant correlation was obtained between PexCO2 and P(a)CO2 (r = 0.79; p < 0.05); there was also a strong agreement between PexCO2 and P(a)CO2 with a gradient of 3.4 +/- 1.9 mmHg. During stable hypothermia, a significant correlation was obtained between PexCO2 and the temperature corrected-P(a)CO2 (r = 0.78; p < 0.05); also, there was a strong agreement between PexCO2 and temperature corrected-P(a)CO2 with a gradient of 2.8 +/- 2.0 mmHg. During stable hypothermia, a significant correlation was obtained between PexCO2 and the temperature uncorrected-P(a)CO2 (r = 0.61; p < 0.05); however, there was a poor agreement between PexCO2 and the temperature uncorrected-P(a)CO2 with a gradient of 13.2 +/- 3.8 mmHg. Oxygenator exhaust capnography could be used as a mean for continuously monitoring P(a)CO2 during normothermic phase of cardiopulmonary bypass as well as the temperature-corrected P(a)CO2 during the stable hypothermic phase of CPB.     

Capnography rapidly confirmed correct endotracheal tube placement during resuscitation of extremely low birthweight babies (< 1000 g)

During neonatal resuscitation, the routine use of capnography to verify correct placement of the endotracheal tube is not an established international practice. We present four cases that illustrate the successful use of immediate capnography to verify correct tracheal tube placement even in extremely low birthweight (ELBW) prematures (< 1000 g) during resuscitation. Based on this limited experience, we reached institutional consensus among paediatricians and anaesthesiologists that capnography should become standard monitoring during all endotracheal intubations in premature babies.     

Randomized Clinical Trial of Propofol With and Without Alfentanil for Deep Procedural Sedation in the Emergency Department

Objectives: The objectives were to compare the efficacy, occurrence of adverse events, and recovery duration of propofol with and without alfentanil for use in procedural sedation in the emergency department (ED). Methods: This was a randomized nonblinded prospective trial of adult patients undergoing procedural sedation for painful procedures in the ED. Patients with pain before the procedure were given intravenous (IV) morphine sulfate until their pain was adequately treated at least 20 minutes before starting the procedure. Patients received 1 mg/kg propofol either with or without a supplemental dose of 10 μg/kg alfentanil for deep procedural sedation. Doses, vital signs, nasal end‐tidal CO₂ (ETCO₂), pulse oximetry, and bispectral electroencephalographic (EEG) analysis scores were recorded. Subclinical respiratory depression was defined as a change in ETCO₂ of >10 mmHg, an oxygen saturation of <92% at any time, or an absent ETCO₂ waveform at any time. Clinical events related to respiratory depression were noted during the procedure, including the addition of or increase in the flow rate of supplemental oxygen, the use of a bag‐valve mask apparatus, airway repositioning, or stimulation to induce breathing. After the procedure, patients were asked if they experienced pain during the procedure or had recall of the procedure. Results: A total of 150 patients were enrolled; 146 underwent sedation and were included in the analysis. Seventy‐four patients received propofol, and 71 received propofol with alfentanil. No clinically significant complications were noted. Subclinical respiratory depression was seen in 24/74 patients in the propofol group and 30/71 patients in the propofol/alfentanil group (effect size = 9.8%, 95% CI = –5.8% to 25.5%). Clinical signs of respiratory depression included an increase in supplemental oxygen use in 25 of the 74 propofol patients and 31 of the 71 propofol/alfentanil patients (effect size 9.9%, 95% CI = –5.9% to 25.7%), the use of bag‐valve mask apparatus in seven patients in the propofol group and 12 in the propofol/alfentanil group (effect size = 5.6%, 95% CI = –3.5% to 18.4%), airway repositioning in 13 propofol patients and 20 propofol/alfentanil patients (effect size = 10.6%, 95% CI = –3.0% to 24.2%), and stimulation to induce breathing in 11 propofol patients and 20 propofol/alfentanil patients (effect size = 13.3%, 95% CI = 0.1% to 26.5%). The total time of the procedure was longer for the alfentanil/propofol group (median = 11 minutes, range = 5–22 minutes) than for the propofol group (median = 9 minutes, range = 1 to 43 minutes; effect size = 1.93 minutes, 95% CI = 0.73 to 2.58, p = 0.02). Pain during the procedure was reported by 10 of the 74 patients in the propofol group and 7 of the 71 patients in the propofol/alfentanil group (effect size = 4.5%, 95% CI = –6.8% to 14.1%). Recall of some part of the procedure was reported by 12 patients in the propofol group and 9 in the propofol/alfentanil group (effect size = 3.5%, 95% CI = –7.9% to 15.0%). All procedures were successfully completed. Conclusions: The use of supplemental alfentanil with propofol for procedural sedation did not result in a difference in reported pain or recall immediately after the procedure. There was an increase in the proportion of patients who required stimulation to induce respiration during the procedure in patients who received propofol with supplemental alfentanil. The addition of supplemental opioid to procedural sedation with propofol does not appear beneficial.