End-tidal CO2 Values Research Articles

Early point-of-care echocardiography as a predictive factor for absence of return of spontaneous circulatory in out-of-hospital cardiac arrests: A multicentre observational study

IntroductionEarly assessment of the prognosis of a patient in cardiac arrest during cardiopulmonary resuscitation is highly challenging. This study aims to evaluate the predictive outcome value of early point-of-care ultrasound (POCUS) in out-of-hospital settings. MethodsThis observational, prospective, multicentre study’s primary endpoint was the positive predictive value (PPV) of POCUS cardiac standstill within the first 12 min of advanced life support (ALS) initiation in determining the absence of return of spontaneous circulation (ROSC). A multivariate logistic regression model was constructed with adjustments for known predictive variables typically used in termination of resuscitation (TOR) rules. ResultsA total of 293 patients were analysed, with a mean age of 66.6 ± 14.6 years, and a majority were men (75.8%). POCUS was performed on average 7.9 ± 2.6 min after ALS initiation. Among patients with cardiac standstill (72.4%), 16.0% achieved ROSC compared with 48.2% in those with visible cardiac motions. The PPV of early POCUS cardiac standstill for the absence of ROSC was 84.0%, 95% CI [78.3–88.6]. In multivariable analysis, only POCUS cardiac standstill (adjusted odds ratio [aOR] 3.89, 95% CI [1.86–8.17]) and end-tidal CO2 (ETCO2) value ≤37 mmHg (aOR 4.27, 95% CI [2.21–8.25]) were associated with the absence of ROSC. ConclusionEarly POCUS cardiac standstill during CPR for out-of-hospital cardiac arrest was a reliable predictor of the absence of ROSC. However, its presence alone was not sufficient to determine the termination of resuscitation efforts.Trial registration:ClinicalTrials.gov Identifier: NCT 03494153. Registered March 29, 2018.

Standardisation facilitates reliable interpretation of ETCO2 during manual cardiopulmonary resuscitation

BackgroundInterpretation of end-tidal CO2 (ETCO2) during manual cardiopulmonary resuscitation (CPR) is affected by variations in ventilation and chest compressions. This study investigates the impact of standardising ETCO2 to constant ventilation rate (VR) and compression depth (CD) on absolute values and trends. MethodsRetrospective study of out-of-hospital cardiac arrest cases with manual CPR, including defibrillator and clinical data. ETCO2, VR and CD values were averaged by minute. ETCO2 was standardised to 10 vpm and 50 mm. We compared standardised (ETs) and measured (ETm) values and trends during resuscitation. ResultsOf 1,036 cases, 287 met the inclusion criteria. VR was mostly lower than recommended, 8.8 vpm, and highly variable within and among patients. CD was mostly within guidelines, 49.8 mm, and less varied. ETs was lower than ETm by 7.3 mmHg. ETs emphasized differences by sex (22.4 females vs. 25.6 mmHg males), initial rhythm (29.1 shockable vs. 22.7 mmHg not), intubation type (25.6 supraglottic vs. 22.4 mmHg endotracheal) and return of spontaneous circulation (ROSC) achieved (34.5 mmHg) vs. not (20.1 mmHg). Trends were different between non-ROSC and ROSC patients before ROSC (–0.3 vs. + 0.2 mmHg/min), and between sustained and rearrest after ROSC (–0.7 vs. –2.1 mmHg/min). Peak ETs was higher for sustained than for rearrest (53.0 vs. 42.5 mmHg). ConclusionStandardising ETCO2 eliminates effects of VR and CD variations during manual CPR and facilitates comparison of values and trends among and within patients. Its clinical application for guidance of resuscitation warrants further investigation.

Relationship between ETCO2 and PaCO2 under Changing Capnogram in Ventilated Infants with NAVA: An Observational Study.

This observational study evaluated the validity of end-tidal CO2 (ETCO2) as a surrogate for arterial PCO2 (PaCO2) in infants on neurally adjusted ventilatory assist (NAVA), particularly considering the influence of variable spontaneous breathing on capnography waveforms. The study involved 16 infants, analyzing 50 paired ETCO2 and PaCO2 values. Deming regression analysis highlighted a notably stronger correlation for maximum ETCO2 (r2 = 0.6783, p <0.0001) compared to mean ETCO2 (r2 = 0.5686, p <0.0001) and demonstrated a significantly weaker association for minimum ETCO2 (r2 = 0.1838). These findings emphasize the superior predictive value of maximum ETCO2 in estimating PaCO2, advocating its reliable use in clinical monitoring, especially given the dynamic capnography associated with NAVA's variable pressures. The results suggest ETCO2's potential to enhance noninvasive respiratory management, reduce the frequency of blood sampling, and improve overall care for infants requiring mechanical ventilation.

End-tidal carbon dioxide after sodium bicarbonate infusion during mechanical ventilation or ongoing cardiopulmonary resuscitation

PurposeEnd-tidal CO2 is used to monitor the ventilation status or hemodynamic efficacy during mechanical ventilation or cardiopulmonary resuscitation (CPR), and it may be affected by various factors including sodium bicarbonate administration. This study investigated changes in end-tidal CO2 after sodium bicarbonate administration. Materials and methodsThis single-center, prospective observational study included adult patients who received sodium bicarbonate during mechanical ventilation or CPR. End-tidal CO2 elevation was defined as an increase of ≥20% from the baseline end-tidal CO2 value. The time to initial increase (lag time, Tlag), time to peak (Tpeak), and duration of the end-tidal CO2 rise (Tduration) were compared between the patients with spontaneous circulation (SC group) and those with ongoing resuscitation (CPR group). ResultsThirty-three patients, (SC group, n = 25; CPR group, n = 8), were included. Compared with the baseline value, the median values of peak end-tidal CO2 after sodium bicarbonate injection increased by 100% (from 21 to 41 mmHg) in all patients, 89.5% (from 21 to 39 mmHg) in the SC group, and 160.2% (from 15 to 41 mmHg) in the CPR group. The median Tlag was 17 s (IQR: 12–21) and the median Tpeak was 35 s (IQR: 27–52). The median Tduration was 420 s (IQR: 90–639). The median Tlag, Tpeak, and Tduration were not significantly different between the groups. Tduration was associated with the amount of sodium bicarbonate for SC group (correlation coefficient: 0.531, p = 0.006). ConclusionThe administration of sodium bicarbonate may lead to a substantial increase in end-tidal CO2 for several minutes in patients with spontaneous circulation and in patients with ongoing CPR. After intravenous administration of sodium bicarbonate, the use of end-tidal CO2 pressure as a physiological indicator may be limited.

Sports despite masks: no negative effects of FFP2 face masks on cardiopulmonary exercise capacity in children

Face masks were recognized as one of the most effective ways to prevent the spread of the COVID-19 virus in adults. These benefits were extended to children and adolescents. However, the fear of negative consequences from wearing a face mask during physical exercise led to cancellations of physical education lessons. This further decreased the amount of physical activity available to children and adolescents during the pandemic. However, there is little published data on the potential adverse effects of wearing the most effective and partially mandatory FFP2/N95 face masks during PE or physical activity (PA) in this age. Even though the pandemic has been declared as passed by the WHO, the rise of a new pandemic and thus the use of face masks for limiting its spread is inevitable, so we need to be better prepared for alternative options to lockdown and limitation of PA in such a scenario. Twenty healthy children aged 8–10 years performed two identical cardiopulmonary exercise tests as an incremental step test on a treadmill within an interval of 2 weeks, one time without wearing a protective mask and one time wearing an FFP2 mask. The cardiopulmonary exercise parameter and especially the end-expiratory gas exchange for oxygen and carbon dioxide (petO2 and petCO2) were documented for each step, at rest and 1 min after reaching physical exhaustion. Twelve boys (mean age 8.5 ± 1.4 years) and 8 girls (mean age 8.8 ± 1.4 years) showed no adverse events until maximal exertion. The mean parameters measured at peak exercise did not differ significantly between both examinations (mean peak VO2 = 42.7 ± 9.5 vs 47.8 ± 12.9 ml/min/kg, p = 0.097, mean O2pulse 7.84 ± 1.9 ml/min vs. 6.89 ± 1.8, p = 0.064, mean VE/VCO2slope 33.4 ± 5.9 vs. 34.0 ± 5.3, p = 0.689). The only significant difference was the respiratory exchange rate (RER, 1.01 ± 0.08 vs 0.95 ± 0.08, p = 0.004). The measured respiratory gases (end-tidal O2 and CO2) decreased and respectively increased significantly in almost every step when wearing an FFP2 mask. However, these levels were well below hypercapnia and above hypoxia.Conclusion: In this study, no significant differences in the cardiorespiratory function at peak exercise could be discerned when wearing an FFP2/N95 face mask. While the end-tidal values for CO2 increased significantly and the end-tidal values for O2 decreased significantly, these values did never reach levels of hypercapnia or hypoxia. Furthermore, the children terminated the exercise at a lower RER and heart rate (HR) suggesting a subconscious awareness of the higher strain. Since the detrimental effects of limiting sports during the pandemic are well documented, stopping PE lessons altogether because of the minor physiological effects of wearing these masks instead of simply stopping pushing children to perform at their best seems premature and should be reconsidered in the future.What is Known:• Wearing a face mask has an influence on psychological, social, and physiological functions in adults.• Because of the observed effects of wearing face masks in adults, physical activity in children was limited during the pandemic.What is New:• Wearing an FFP2/N95 mask during physical activity did not lead to hypercapnia or hypoxia in children in this study.• Even though end-tidal CO2 values were significantly higher and end-tidal O2 values significantly lower when wearing an FFP2/N95 face mask, no pathological values were reached.

Abstract 141: Automated Head-Up Cardiopulmonary Resuscitation Increased End Tidal Co2 in Patients With Out-of-Hospital Cardiac Arrest Compared With Conventional CPR: A Prospective Before-After Interventional Study

Background: Little is known in humans about the physiological effects of the combination of automated Head-Up cardiopulmonary resuscitation CPR, active compression-decompression CPR and an impedance threshold device (ITD). This new approach, termed AHUP-CPR, improves perfusion of vital organs and lowers intracranial pressure compared with conventional (C)CPR in animal models of cardiac arrest. This study tested the hypothesis that AHUP-CPR treatment would increase end tidal CO2 (ETCO2), a circulation surrogate, more than C-CPR in out-of-hospital cardiac arrest (OHCA) patients. Method: Prospective before-after interventional study of witnessed OHCA patients. C-CPR and AHUP-CPR were performed by firefighters who measured ETCO2. AHUP-CPR was delivered using a LUCAS AD (5 cm of compression and 3 cm active decompression) (Stryker Medical, USA), an EleGARD Patient Positioning System (AdvancedCPR Solutions, USA), and an ITD (ResQPOD-16, Zoll, USA). The study was performed in the greater Grenoble France region in four different fire stations. The primary endpoint was the measurement of maximum EtCO2 during CPR. Results are presented as mean ± standard deviation. Results: Baseline characteristics (age, sex, arrest location, initial rhythm, bystander CPR, witnessed) were not statistically different between groups.EtCO2 was higher for patients treated with AHUP-CPR (n=63) compared to the C-CPR (n=59) (41±18 vs. 30.2 mmHg, p&lt;0.001). This difference was significant for shockable (45±13 vs. 34±12 mmHg, p=0.03) and non-shockable (40±19 vs. 28±13 mmHg, p=0.004) rhythms, respectively. The calculated difference between the maximum and first recorded ETCO2 values was 6.3 ± 20.4 in the C-CPR arm versus 21.1 ± 20.6 in the AHUP-CPR group (P&lt;0.001). A total of 29% (n=18) of the AHUP patients vs. 22 % (n=13) were admitted alive to the hospital (P=0.34). Conclusion: Results from this first prospective clinical trial on AHUP-CPR demonstrated that ETCO2 values were significantly higher after AHUP-CPR versus C-CPR, regardless of the presenting rhythm. Using ETCO2 as a surrogate for circulation, these findings confirm animal studies showing AHUP-CPR provides significantly more vital organ blood flow to patients in OHCA compared with C-CPR.

Association between prehospital end-tidal carbon dioxide levels and mortality in patients with suspected severe traumatic brain injury

PurposeSevere traumatic brain injury is a leading cause of mortality and morbidity, and these patients are frequently intubated in the prehospital setting. Cerebral perfusion and intracranial pressure are influenced by the arterial partial pressure of CO2 and derangements might induce further brain damage. We investigated which lower and upper limits of prehospital end-tidal CO2 levels are associated with increased mortality in patients with severe traumatic brain injury.MethodsThe BRAIN-PROTECT study is an observational multicenter study. Patients with severe traumatic brain injury, treated by Dutch Helicopter Emergency Medical Services between February 2012 and December 2017, were included. Follow-up continued for 1 year after inclusion. End-tidal CO2 levels were measured during prehospital care and their association with 30-day mortality was analyzed with multivariable logistic regression.ResultsA total of 1776 patients were eligible for analysis. An L-shaped association between end-tidal CO2 levels and 30-day mortality was observed (p = 0.01), with a sharp increase in mortality with values below 35 mmHg. End-tidal CO2 values between 35 and 45 mmHg were associated with better survival rates compared to < 35 mmHg. No association between hypercapnia and mortality was observed. The odds ratio for the association between hypocapnia (< 35 mmHg) and mortality was 1.89 (95% CI 1.53–2.34, p < 0.001) and for hypercapnia (≥ 45 mmHg) 0.83 (0.62–1.11, p = 0.212).ConclusionA safe zone of 35–45 mmHg for end-tidal CO2 guidance seems reasonable during prehospital care. Particularly, end-tidal partial pressures of less than 35 mmHg were associated with a significantly increased mortality.

Hastanede yatan COVID-19 hastalarında hastalığın ilerlemesini ve mortalite riskini tahmin etmede ETCO2 değerlerinin kullanılabilirliği

Aim: End-tidal CO2 (ETCO2) levels are reflective of the ventilatory and metabolic/perfusion status of a patient, regardless of his/her SpO2 values. This study aimed to investigate the utility of ETCO2values in predicting the need for intubation, ICU admission, and mortality in hospitalized patients with COVID-19 pneumonia. &#x0D; Material and Method: A total of 108 hospitalized patients with COVID-19 pneumonia were included. Data on respiratory parameters (oxygen saturation, ETCO2, and respiratory rate [RR]- with and without O2 [w/wo O2]) and laboratory parameters were recorded. &#x0D; Results: The need forintensive care unit(ICU) admission was associated with significantly higher ETCO2 values (wO2:27.9 (4.6) vs. 18.6(8.4), p=0.040; woO2: 30.1(4.9) vs. 23.8(6.9), p=0.040). Mortality was associated with higher likelihood of higher RR (wO2:32.4(5.8) vs. 24.6(6.8), p=0.002) and lower oxygen saturation (wO2:92.9(3.8) vs. 95.5(4.2), p=0.025; woO2:87.1(5.7) vs. 91.8(6.6), p=0.013). Presence vs. lack of intubation need was associated with significantly increased likelihood of saturation (wO2:93.1(5.3) vs. 95.9(3.8), p=0.013; woO2:87.6(8.3) vs. 92.3(5.9), p=0.007). Hospital discharge vs. ICU stay was associated with significantly higher ETCO2 values (wO2:27.9 (4.6) vs. 18.6(8.4), p=0.040; woO2: 30.1(4.9) vs. 23.8(6.9), p=0.040)&#x0D; Conclusion: Our findings revealed the association of decreased ETCO2 (w/wo O2) values with a lower likelihood of hospital discharge and increased likelihood of ICU transfer. Low oxygen saturation levels related the increased risk of both intubation need and mortality in hospitalized COVID-19 patients.

Lung mechanics during video-assisted abdominal surgery in Trendelenburg position: a cross-sectional propensity-matched comparison between classic laparoscopy and robotic-assisted surgery

BackgroundVideo-assisted surgery has become an increasingly used surgical technique in patients undergoing major thoracic and abdominal surgery and is associated with significant perioperative respiratory and cardiovascular changes. The aim of this study was to investigate the effect of intraoperative pneumoperitoneum during video-assisted surgery on respiratory physiology in patients undergoing robotic-assisted surgery compared to patients undergoing classic laparoscopy in Trendelenburg position.MethodsTwenty-five patients undergoing robotic-assisted surgery (RAS) were compared with twenty patients undergoing classic laparoscopy (LAS). Intraoperative ventilatory parameters (lung compliance and plateau airway pressure) were recorded at five specific timepoints: after induction of anesthesia, after carbon dioxide (CO2) insufflation, one-hour, and two-hours into surgery and at the end of surgery. At the same time, arterial and end-tidal CO2 values were noted and arterial to end-tidal CO2 gradient was calculated.ResultsWe observed a statistically significant difference in plateau pressure between RAS and LAS at one-hour (26.2 ± 4.5 cmH2O vs. 20.2 ± 3.5 cmH2O, p = 0.05) and two-hour intervals (25.2 ± 5.7 cmH2O vs. 17.9 ± 3.1 cmH2O, p = 0.01) during surgery and at the end of surgery (19.9 ± 5.0 cmH2O vs. 17.0 ± 2.7 cmH2O, p = 0.02). Significant changes in lung compliance were also observed between groups at one-hour (28.2 ± 8.5 mL/cmH2O vs. 40.5 ± 13.9 mL/cmH2O, p = 0.01) and two-hour intervals (26.2 ± 7.8 mL/cmH2O vs. 54.6 ± 16.9 mL/cmH2O, p = 0.01) and at the end of surgery (36.3 ± 9.9 mL/cmH2O vs. 58.2 ± 21.3 mL/cmH2O, p = 0.01). At the end of surgery, plateau pressures remained higher than preoperative values in both groups, but lung compliance remained significantly lower than preoperative values only in patients undergoing RAS with a mean 24% change compared to 1.7% change in the LAS group (p = 0.01). We also noted a more significant arterial to end-tidal CO2 gradient in the RAS group compared to LAS group at one-hour (12.9 ± 4.5 mmHg vs. 7.4 ± 4.4 mmHg, p = 0.02) and two-hours interval (15.2 ± 4.5 mmHg vs. 7.7 ± 4.9 mmHg, p = 0.02), as well as at the end of surgery (11.0 ± 6.6 mmHg vs. 7.0 ± 4.6 mmHg, p = 0.03).ConclusionVideo-assisted surgery is associated with significant changes in lung mechanics after induction of pneumoperitoneum. The observed changes are more severe and longer-lasting in patients undergoing robotic-assisted surgery compared to classic laparoscopy.

Near-Infrared Spectroscopy Usefulness in Validation of Hyperventilation Test.

Background: The hyperventilation test is used in clinical practice for diagnosis and therapeutic purposes; however, in the absence of a standardized protocol, the procedure varies significantly, predisposing tested subjects to risks such as cerebral hypoxia and ischemia. Near-infrared spectroscopy (NIRS), a noninvasive technique performed for cerebral oximetry monitoring, was used in the present study to identify the minimum decrease in the end-tidal CO2 (ETCO2) during hyperventilation necessary to induce changes on NIRS. Materials and Methods: We recruited 46 volunteers with no preexisting medical conditions. Each subject was asked to breathe at a baseline rate (8–14 breaths/min) for 2 min and then to hyperventilate at a double respiratory rate for the next 4 min. The parameters recorded during the procedure were the regional cerebral oxyhemoglobin and deoxyhemoglobin concentrations via NIRS, ETCO2, and the respiratory rate. Results: During hyperventilation, ETCO2 values dropped (31.4 ± 12.2%) vs. baseline in all subjects. Changes in cerebral oximetry were observed only in those subjects (n = 30) who registered a decrease (%) in ETCO2 of 37.58 ± 10.34%, but not in the subjects (n = 16) for which the decrease in ETCO2 was 20.31 ± 5.6%. According to AUC-ROC analysis, a cutoff value of ETCO2 decrease >26% was found to predict changes in oximetry (AUC-ROC = 0.93, p < 0.0001). Seven subjects reported symptoms, such as dizziness, vertigo, and numbness, throughout the procedure. Conclusions: The rise in the respiratory rate alone cannot effectively predict the occurrence of a cerebral vasoconstrictor response induced by hyperventilation, and synchronous ETCO2 and cerebral oximetry monitoring could be used to validate this clinical test. NIRS seems to be a useful tool in predicting vasoconstriction following hyperventilation.

Laparoscopic versus Open Ovariectomy in Bitches: Changes in Cardiorespiratory Values, Blood Parameters, and Sevoflurane Requirements Associated with the Surgical Technique.

Simple SummaryLaparoscopic neutering techniques are widely used in veterinary medicine due to their numerous advantages compared to open ones. However, laparoscopy requires the creation of pneumoperitoneum to establish a working space, and it has been related to the occurrence of pathophysiological alterations. The objective of this study was to evaluate the potential global systemic changes associated to the establishment of the pneumoperitoneum in laparoscopic ovariectomy and to compare them with those determined in conventional open surgery in dogs. Additionally, we evaluated the gas anesthetic requirements based on the surgical technique. The results of our study suggested that the cardiorespiratory alterations related to pneumoperitoneum seemed to be well-tolerated and reversible after CO2 deflation. Regarding the anesthetic gas evaluation, we determined higher requirements during ovarian resection in the open ovariectomy group. In conclusion, laparoscopic neutering procedures should be currently recommended by veterinarians due to their lower invasiveness and resulting complications. Nevertheless, a thorough understanding of the changes associated with pneumoperitoneum is essential to plan and obtain an adequate perioperative management.The aim of this study was to examine the cardiorespiratory and blood changes associated with pneumoperitoneum (PNP) in laparoscopic ovariectomy (LAP Ove), as well as sevoflurane requirements, comparing them to those determined in open surgery (LPT Ove). The study was performed in 16 bitches submitted to LAP or LPT Ove. The cardiorespiratory and end-tidal sevoflurane concentration values were recorded as follows: at the beginning of surgery (T1), after the right ovary resection (T2), after the left ovary resection (T3), and after surgical closure (T4). Blood samples were taken before and after PNP. Among the cardiorespiratory parameters, no differences were observed in the values of end-tidal CO2, minute volume, and heart rate. In the LAP Ove group, a significant increase in inspiratory pressures and a decreased compliance were identified at T2 and T3. Significant higher arterial pressure values were observed in both groups at T2 and T3, with this increase especially marked at T2 in the LPT Ove group. Sevoflurane requirements were significantly higher in the LPT group during ovarian resection. Finally, in terms of the hematochemical parameters, statistical differences were recorded between pre- and post-operative assessments, but not between both surgical groups. The pathophysiological effects associated with PNP seemed to be transient and well-tolerated by healthy dogs.

This Month in Anesthesiology

This Month in Anesthesiology

The Cardiopulmonary Effects of Medical Masks and Filtering Facepiece Respirators on Healthy Health Care Workers in the Emergency Department: A Prospective Cohort Study

BackgroundInternational COVID-19 guidelines recommend that health care workers (HCWs) wear filtering facepiece (FFP) respirators to reduce exposure risk. However, there are concerns about FFP respirators causing hypercapnia via rebreathing carbon dioxide (CO2). Most previous studies measured the physiological effects of FFP respirators on treadmills or while resting, and such measurements may not reflect the physiological changes of HCWs working in the emergency department (ED). ObjectiveOur aim was to evaluate the physiological and clinical impacts of FFP type II (FFP2) respirators on HCWs during 2 h of their day shift in the ED. MethodsWe included emergency HCWs in this prospective cohort study. We measured end-tidal CO2 (ETCO2), mean arterial pressure (MAP), respiratory rate (RR), and heart rate values and dyspnea scores of subjects at two time points. The first measurements were carried out with medical masks while resting. Subjects then began their day shift in the ED with medical mask plus FFP2 respirator. We called subjects after 2 h for the second measurement. ResultsThe median age of 153 healthy volunteers was 24.0 years (interquartile range 24.0–25.0 years). Subjects’ MAP, RR, and ETCO2 values and dyspnea scores were significantly higher after 2 h. Median ETCO2 values increased from 36.4 to 38.8 mm Hg. None of the subjects had hypercapnia symptoms, hypoxia, or other adverse effects. ConclusionWe did not observe any clinical reflection of these changes in physiological values. Thus, we evaluated these changes to be clinically insignificant. We found that it is safe for healthy HCWs to wear medical masks plus FFP2 respirators during a 2-h working shift in the ED.

Preemptive analgesic effect of ultrasonography-guided transversus abdominis plane block performed by adding dexamethasone to bupivacaine

The objective of this study was to evaluate the preemptive analgesic effect of ultrasound-guided transversus abdominis plane block performed with bupivacaine or adding dexamethasone on bupivacaine in laparoscopic cholecystectomy. This retrospective study was conducted on a total of 84 patients who underwent ultrasound-guided TAP block in laparoscopic cholecystectomy. Patients were divided into two groups: Group Bupivacaine (Group B) and Group Bupivacaine+Dexamethasone (Group B+D). Intraoperative hemodynamic changes, intraoperative remifentanil consumption, postoperative visual analog scale scores, tramadol consumption in 24 hours postoperatively, and postoperative first analgesic time were obtained from the records and compared between the groups. There were no statistically significant differences between both groups in terms of intraoperative heart rate, mean arterial pressure, oxygen saturation, and end-tidal CO2 values. Postoperative visual analog scale scores, doses of remifentanil and total tramadol, and time of receiving the first analgesic were similar. Dexamethasone can be added to the bupivacaine for the TAP block without major side effects. Adding dexamethasone to bupivacaine in transverse abdominis plane block performed in laparoscopic cholecystectomy procedures did not create a significant difference in VAS score. We think that the use of dexamethasone does not have an additional analgesic effect. However, our results should be supported by further studies.

Correlation of the end-tidal CO2 value with arterial blood gas parameters – evaluation of the treatment efficacy of COPD exacerbation in the emergency department

Introduction and aim. Painful, invasive, and expensive arterial blood gas (ABG) analysis is required in the diagnosis, follow-up, treatment, and even discharge of patients with chronic obstructive pulmonary disease (COPD). This study aimed to compare the end-tidal carbon dioxide (ETCO2) value, which allows non-invasive, painless, low-cost, and continuous monitoring, with ABG parameters, in the evaluation of the treatment efficacy of COPD exacerbation. Material and methods. The study was prospectively conducted with patients who presented to the emergency department with COPD exacerbation. ABG analysis and ETCO2 measurement were simultaneously performed in patients with COPD exacerbation at the time of arrival and after treatment, and were statistically compared. Results. The study included a total of 216 patients, of whom 57.4% were male. The mean age of the patients was 67.3±13.9 years. The ETCO2 values of the patients at arrival and after COPD exacerbation treatment were 39.2±10 and 37.3±9, respectively, and a statistically significant difference was determined (p=0.001). The partial pressure of pCO2 values measured at arrival and after treatment were 40.85±10.54 and 38.74±9.25, respectively, and it was statistically significant (p=0.001). A strong positive and statistically significant correlation was found between the ETCO2 and pCO2 values both at arrival and after COPD exacerbation treatment (r=0.840; p&lt;0.001 and r=0.872; p&lt;0.001, respectively). The Bland-Altman plot was constructed for the agreement between ETCO2 and pCO2 at both evaluation times. Conclusion. ETCO2 measurement could accurately predict the pCO2 of patients with COPD at arrival and after COPD exacerbation treatment. Also, ETCO2 may be useful in cases where pCO2 cannot be used.

The high impulse, palm lift technique for chest compression: Prospective, experimental, pilot study.

The classic technique of high quality chest compression (HQCC) during cardiopulmonary resuscitation (CPR) is based on the International Liaison Committee on Resuscitation (ILCOR) guidelines which specify that the rescuer's hands should maintain constant contact with the chest surface but should not lean upon it, in order to provide full chest recoil. Since end-tidal CO2 (EtCO2) values have been shown to be a reliable indicator of CPR quality, we examined a method where classic HQCC was modified by a high impulse and palm lifting (HIPL) technique which merged rapid forceful compression with disconnection of the rescuer's palm from the patient's sternum during the recoil phase. The object of the study was to detect any differences in HIPL EtCO2 values in comparison with those from classic HQCC. We report a prospective pilot study in which we compared EtCO2 readings achieved during 2min of classic HQCC technique with readings after implementing 2min of the HIPL technique during out-of-hospital CPR, provided by medical emergency response teams for cases of cardiac arrest. EtCO2 values obtained from16 cases who received HQCC followed by HIPL compressions showed a significant difference (p=0.037) between the two techniques. Mean±SD EtCO2 values after 2min of each technique were: HQCC: 18±9mmHg; HIPL: 27±11mmHg; followed by a further 2min of HQCC: 19±11mmHg. Linear regression showed that the differences in EtCO2 were associated with non - significant changes in ventilation rate (p=0.493) and chest compression rate (p=0.889). The results obtained suggest that modifying HQCC with the HIPL technique led to a significant increase in EtCO2 values in comparison with classic HQCC, indicating an improvement in circulation during CPR. We think that these encouraging early results warrant a larger multi - centre study of HIPL.

Amiodarone and amplitude spectral area of ventricular fibrillation in patients with out-of-hospital cardiac arrest

Abstract Background Ventricular fibrillation is the most common cause of out-of-hospital cardiac arrest (OHCA) and the use of antiarrhythmic drug therapy is usually recommended in addition to defibrillation. The role of the amplitude spectral area (AMSA) of ventricular fibrillation as a predictor of defibrillation efficacy has been established, while the existing data in favour of the use of amiodarone has been assessed with poor evidence and controversy. Purpose The aim of our study is to evaluate whether the administration of amiodarone during resuscitation could affect AMSA values. Materials All the OHCAs with a shockable presenting rhythm and attempted resuscitation which occurred from January 2015 to June 2019 in the province of Pavia were considered. Both the end-tidal CO2 (ETCO2) and AMSA values were calculated by retrospectively analyzing the data collected by the Corpuls 3 monitors/defibrillators (Corpuls, Kaufering, Germany) used in the territory and by considering a pre-shock interval of 2 seconds. Results Among a total of 3413 OHCAs, resuscitation was attempted in 2195 cases (64%), 377 (17%) had a shockable presenting rhythm and in 112 cases (3.4%) it was possible to obtain the values of ETCO2 and AMSA for a total of 391 shocks. Among these, 301 shocks (77%) were delivered to patients who received amiodarone during resuscitation. The success rate of each single shock was similar in the two groups but with an unfavorable trend for amiodarone (amiodarone 43.5% vs no amiodarone 54.4%, p=0.07). AMSA was significantly lower in patients treated with amiodarone (7.9 mV·Hz, IQR 5.4–12.2 vs 10.6 mV·Hz, IQR 7.1–14.1; p&amp;lt;0.001). According to a multivariate analysis, the administration of amiodarone and the time to shock were independent predictors of AMSA values. Lastly, on a sample of 124 shocks, homogeneous for age, sex, ETCO2, outcome of resuscitation and randomly matched, the AMSA of patients who received amiodarone was significantly lower (7.2 mV·Hz, IQR 7.2–11.7 vs 9.7 mV·Hz, IQR 6.7–12.5; p=0.02). Conclusions Our results indicate that amiodarone administration is associated with lower values of AMSA. Since higher AMSA values are known to be associated with a higher probability of shock rate success, this could help to better clarify the controversial role of amiodarone administration in patients with OHCA. Funding Acknowledgement Type of funding sources: None.

REBOA-Assisted Resuscitation in Non-Traumatic Cardiac Arrest due to Massive Pulmonary Embolism: A Case Report with Physiological and Practical Reflections

We present the case of a 36-year-old woman who suffered from and ultimately did not survive a non-traumatic out-of-hospital cardiac arrest (NTCA) likely due to massive pulmonary embolism. The resuscitation attempt included the use of a resuscitative endovascular balloon occlusion of the aorta (REBOA) catheter which resulted in a return of spontaneous circulation and distinct improvements in arterial blood pressure, end-tidal CO2 and cerebral oximetry values. This suggests that the use of REBOA has the physiological basis and potential to improve the rate of both survival and favorable neurologic outcome and warrants further study.

Bispectral index scores predicting complications after tracheal intubation

BackgroundTracheal intubation is a procedure that may cause various complications. The primary aim of this study is to investigate whether the Bispectral Index™ (BIS) can predict tracheal intubation complications sooner than other monitoring parameters. MethodsA total of 55 consecutive patients were intubated. Sociodemographic data, the reason for tracheal intubation, diagnosis, starting dose or dose increase of a vasopressor drug, use of sedatives and muscle-relaxing agents, vital signs, BIS scores, and end-tidal CO2 values before the procedure, during laryngoscopy, and within 30 min after tracheal intubation were recorded along with their tracheal intubation-related complications. ResultsThe mean age of the patients was 75.1 ± 14.4 years. Pneumonia (n = 17, 30.9%) and sepsis (n = 14, 25.5%) were found to be the two most prominent diagnoses. The most common indications for intubation were a low Glasgow Coma Scale score of ≤8 (67.3%) and respiratory failure (61.8%). Postintubation hemodynamic instability developed in 38 patients (69.1%).The BIS value obtained at minute 3 was the lowest among all measurements. Significantly lower values of BIS (minute 3) were found for patients with postintubation hemodynamic instability (46 vs. 72, p = 0.039). Using ketamine (OR = 8.99, 95% CI: 1.60–50.47, p = 0.013) and systoloc blood pressure (OR = 1.03, 95% CI: 1.01–1.05, p = 0.017) were found to be significant risk factors for the development of postintubation hemodynamic instability. ConclusionIn this study, the lowest BIS values were detected at minute three after intubation. The BIS values obtained at minute three were found to be significantly associated with the development of postintubation hemodynamic instability.

Carbon dioxide monitoring in the newborn infant.

Carbon dioxide (CO2 ) monitoring is vital during mechanical ventilation of newborn infants, as morbidity increases when CO2 levels are inappropriate. Our aim was to review the uses and limitations of such noninvasive monitoring methods. Colorimetry is primarily utilized during resuscitation to determine whether successful intubation has occurred. False negative and positive results can however lead to delays in detecting tracheal versus esophageal intubation. Transcutaneous carbon dioxide sensors have limited use during resuscitation, but can be utilized to provide continuous trend data during on-going ventilation. End-tidal capnography can provide clinicians with quantitative end-tidal CO2 (EtCO2 ) values and a continuous real-time capnogram waveform trace. These devices are becoming more widely accepted for use in the neonatal population as the new devices are lightweight with minimal additional dead space. Nevertheless, they have been reported to have variable accuracy when compared to arterial CO2 measurements, however, divergence of results may be related to disease severity rather than technological limitations. During resuscitation EtCO2 can be detected by capnography more rapidly than by colorimetry. Furthermore, capnography can be currently utilized in neonatal research settings to determine the physiological dead space and ventilation inhomogeneity, and thus has potential to be beneficial to clinical care. In conclusion, novel modes of noninvasive carbon dioxide monitoring can be safely and reliably utilized in newborn infants during mechanical ventilation. Future randomized trials should aim to address which device provides the most optimal form of monitoring in different clinical contexts.