Arterial Partial Pressure of Carbon Dioxide and Secondary Brain Injury—6 Degrees of Separation?

Aims/Objectives/BackgroundIn the United Kingdom (UK), 20% of patients with severe traumatic brain injury (TBI) receive pre-hospital emergency anaesthesia (PHEA). Current guidance recommends an end-tidal carbon dioxide (ETCO2) of 4.0–4.5kPa to achieve a low-normal arterial partial pressure of CO2 (PaCO2), and reduce secondary brain injury. This recommendation assumes a 0.5kPa ETCO2-PaCO2 gradient. However, the gradient in the acute phase of TBI is unknown. Our primary aim was to report the ETCO2-PaCO2 gradient of TBI patients at hospital arrival.Methods/DesignA retrospective cohort study of adult patients with serious TBI, who received a PHEA by a pre-hospital critical care team in the East of England between 1st April 2015 to 31st December 2017. Linear regression was performed to test for correlation and reported as R-squared (R2). A Bland-Altman plot was used to test for paired ETCO2 and PaCO2 agreement and reported with 95% confidence intervals (95%CI). ETCO2-PaCO2 gradient data were compared with a two-tailed, unpaired, t-test.Results/Conclusions107 patients were eligible for inclusion. Sixty-seven patients did not receive a PaCO2 sample within 30 minutes of hospital arrival and were therefore excluded. Forty patients had complete data and were included in the final analysis; per protocol.The mean ETCO2-PaCO2 gradient was 1.7 (±1.0) kPa, with only moderate correlation of ETCO2 and PaCO2 at hospital arrival (R2=0.23, p=0.002). The Bland-Altman bias was 1.7 (95%CI 1.4–2.0) kPa with upper and lower limits of agreement of 3.6 (95%CI 3.0–4.1) kPa and -0.2 (95%CI -0.8–0.3) kPa respectively. There was no significant gradient correlation in patients with a co-existing serious thoracic injury (R2=0.13, p=0.10), and this cohort had a larger ETCO2-PaCO2 gradient, 2.0 (±1.1) kPa, p=0.01. Patients who underwent pre-hospital arterial blood sampling had an arrival PaCO2 of 4.7 (±0.2) kPa.Lower ETCO2 targets than previously recommended may be safe and appropriate. The use of pre-hospital PaCO2 measurement is advocated.

Download Full-text

Second-generation laryngeal mask airway as an alternative to endotracheal tube during prolonged laparoscopic abdominal surgery: a comparative analysis of intraoperative gas exchanges

Singapore Medical Journal ◽

10.11622/smedj.2021143 ◽

2021 ◽

Author(s):

S Park ◽

JE Lee ◽

GS Choi ◽

JM Kim ◽

JS Ko ◽

...

Keyword(s):

Carbon Dioxide ◽

Gas Exchange ◽

Laryngeal Mask Airway ◽

Abdominal Surgery ◽

Partial Pressure ◽

Endotracheal Tube ◽

Second Generation ◽

Laryngeal Mask ◽

Arterial Partial Pressure ◽

Prolonged Surgery

Introduction: Despite several advantages over endotracheal tube (ETT), laryngeal mask airway (LMA), which is used in emergencies under difficult airway maintenance conditions, is rarely utilized in prolonged surgery. We compared the variables representing intraoperative gas exchange with second-generation LMA and ETT during prolonged laparoscopic abdominal surgery. Methods: Prolonged surgery was defined as a surgery lasting more than 2 h. In total, 394 patients who underwent laparoscopic liver resection via either second-generation LMA or ETT were retrospectively analysed. Parameters including end-tidal pressure of carbon dioxide (ETCO2), tidal volume (TV), respiratory rate (RR), peak inspiratory pressure (PIP), arterial partial pressure of carbon dioxide (PaCO2), pH, and ratio of arterial partial pressure of oxygen to fractional inspired oxygen (PFR) during surgery were compared between the two groups. In addition, the incidence of postoperative pulmonary complications (PPC) including pulmonary aspiration was also compared. Results: The values of ETCO2, TV, RR and PIP during pneumoperitoneum were comparable between the two groups. Although PaCO2 at 2 h after induction was higher in patients with LMA (40.5 vs. 38.5 mmHg, p < 0.001), the pH and PFR values of the two groups were comparable. The incidence of PPC was not different. Conclusion: During prolonged laparoscopic abdominal surgery, the second-generation LMA facilitates adequate intraoperative gas exchange and represents an alternative to ETT.

Download Full-text

Targeting Arterial Partial Pressure of Carbon Dioxide in Acute Respiratory Distress Syndrome Patients using Extracorporeal Carbon Dioxide Removal

Artificial Organs ◽

10.1111/aor.14127 ◽

2021 ◽

Author(s):

John K. Leypoldt ◽

Jörg Kurz ◽

Jorge Echeverri ◽

Markus Storr ◽

Kai Harenski

Keyword(s):

Carbon Dioxide ◽

Acute Respiratory Distress Syndrome ◽

Respiratory Distress Syndrome ◽

Respiratory Distress ◽

Partial Pressure ◽

Distress Syndrome ◽

Carbon Dioxide Removal ◽

Extracorporeal Carbon Dioxide Removal ◽

Arterial Partial Pressure

Download Full-text

Relationship between plasma levels of leukotriene E4 and arterial partial pressure of carbon dioxide in asthmatic patients

Current Therapeutic Research ◽

10.1016/s0011-393x(05)80638-1 ◽

1993 ◽

Vol 54 (3) ◽

pp. 366-370 ◽

Cited By ~ 2

Author(s):

Kunihiko Shindo ◽

Motonori Fukumura

Keyword(s):

Carbon Dioxide ◽

Partial Pressure ◽

Plasma Levels ◽

Asthmatic Patients ◽

Arterial Partial Pressure

Download Full-text

EFFECTS OF CO2 PNEUMOPERITONEUM ON ARTERIAL PARTIAL PRESSURE OF CARBON DIOXIDE PH, END TIDAL CARBON DIOXIDE AND BICARBONATE IN PATIENTS DURING LAPAROSCOPIC CHOLECYSTECTOMY

Journal of Evolution of Medical and Dental Sciences ◽

10.14260/jemds/2016/534 ◽

2016 ◽

Vol 5 (38) ◽

pp. 2299-2302

Author(s):

Abdul Hakeem ◽

Asif Iqbal ◽

Mohammad Dawood ◽

Basharat Saleem ◽

Abdul Hameed

Keyword(s):

Carbon Dioxide ◽

Laparoscopic Cholecystectomy ◽

Partial Pressure ◽

Co2 Pneumoperitoneum ◽

Arterial Partial Pressure ◽

End Tidal Carbon Dioxide ◽

End Tidal

Download Full-text

End-tidal and arterial carbon dioxide gradient in serious traumatic brain injury after prehospital emergency anaesthesia: a retrospective observational study

Emergency Medicine Journal ◽

10.1136/emermed-2019-209077 ◽

2020 ◽

Vol 37 (11) ◽

pp. 674-679

Author(s):

James Price ◽

Daniel D Sandbach ◽

Ari Ercole ◽

Alastair Wilson ◽

Ed Benjamin Graham Barnard

Keyword(s):

Carbon Dioxide ◽

Traumatic Brain Injury ◽

Brain Injury ◽

Secondary Brain Injury ◽

Moderate Correlation ◽

Hospital Arrival ◽

Prehospital Emergency ◽

The Mean ◽

End Tidal ◽

Emergency Anaesthesia

ObjectivesIn the UK, 20% of patients with severe traumatic brain injury (TBI) receive prehospital emergency anaesthesia (PHEA). Current guidance recommends an end-tidal carbon dioxide (ETCO2) of 4.0–4.5 kPa (30.0–33.8 mm Hg) to achieve a low-normal arterial partial pressure of CO2 (PaCO2), and reduce secondary brain injury. This recommendation assumes a 0.5 kPa (3.8 mm Hg) ETCO2–PaCO2 gradient. However, the gradient in the acute phase of TBI is unknown. The primary aim was to report the ETCO2–PaCO2 gradient of TBI patients at hospital arrival.MethodsA retrospective cohort study of adult patients with serious TBI, who received a PHEA by a prehospital critical care team in the East of England between 1 April 2015 and 31 December 2017. Linear regression was performed to test for correlation and reported as R-squared (R2). A Bland-Altman plot was used to test for paired ETCO2 and PaCO2 agreement and reported with 95% CI. ETCO2–PaCO2 gradient data were compared with a two-tailed, unpaired, t-test.Results107 patients were eligible for inclusion. Sixty-seven patients did not receive a PaCO2 sample within 30 min of hospital arrival and were therefore excluded. Forty patients had complete data and were included in the final analysis; per protocol. The mean ETCO2–PaCO2 gradient was 1.7 (±1.0) kPa (12.8 mm Hg), with moderate correlation (R2=0.23, p=0.002). The Bland-Altman bias was 1.7 (95% CI 1.4 to 2.0) kPa with upper and lower limits of agreement of 3.6 (95% CI 3.0 to 4.1) kPa and −0.2 (95% CI −0.8 to 0.3) kPa, respectively. There was no evidence of a larger gradient in more severe TBI (p=0.29). There was no significant gradient correlation in patients with a coexisting serious thoracic injury (R2=0.13, p=0.10), and this cohort had a larger ETCO2–PaCO2 gradient, 2.0 (±1.1) kPa (15.1 mm Hg), p=0.01. Patients who underwent prehospital arterial blood sampling had an arrival PaCO2 of 4.7 (±0.2) kPa (35.1 mm Hg).ConclusionThere is only moderate correlation of ETCO2 and PaCO2 at hospital arrival in patients with serious TBI. The mean ETCO2–PaCO2 gradient was 1.7 (±1.0) kPa (12.8 mm Hg). Lower ETCO2 targets than previously recommended may be safe and appropriate, and there may be a role for prehospital PaCO2 measurement.

Download Full-text

Automated Detection of Gastric Luminal Partial Pressure of Carbon Dioxide during Cardiovascular Surgery Using the Tonocap

Anesthesiology ◽

10.1097/00000542-200001000-00012 ◽

2000 ◽

Vol 92 (1) ◽

pp. 38-38 ◽

Cited By ~ 64

Author(s):

Elliott Bennett-Guerrero ◽

Michael H. Panah ◽

Carol A. Bodian ◽

Blessy J. Methikalam ◽

John R. Alfarone ◽

...

Keyword(s):

Carbon Dioxide ◽

Partial Pressure ◽

Postoperative Complication ◽

Artery Bypass ◽

Bypass Graft ◽

Automated System ◽

Hospital Death ◽

Published Data ◽

Arterial Partial Pressure ◽

Hemodynamic Variables

Background A new automated system of air tonometry (Tonocap; Datex Ohmeda, Helsinki, Finland) allows for frequent (every 15 min) measurement of gastric luminal partial pressure of carbon dioxide. Its use has not been described in cardiac surgical patients. Methods One hundred patients undergoing coronary artery bypass graft or cardiac valve surgery were enrolled in a prospective cohort study. After anesthetic induction and insertion of a TRIP NGS Catheter (Datex Ohmeda), measurements of gastric luminal partial pressure of carbon dioxide were obtained using the Tonocap, and gastric mucosal pH (pHi) was calculated. The main outcome measure was postoperative complication, defined as either in-hospital death or prolonged postoperative hospitalization (> 14 days). Results Four patients (4%) died, all of multiple-system organ failure, one each on postoperative days 9, 26, 46, and 121. Postoperative complication occurred in 18 patients (18%), all of whom exhibited persistent dysfunction of at least one organ system. Perioperatively, an abnormal pHi (< 7.32) and gastric luminal minus arterial partial pressure of carbon dioxide gap (> 8 mmHg) occurred in 66% and 70% of patients, respectively. Predictors of postoperative complication included postoperative pHi (P = 0.001), gastric luminal partial pressure of carbon dioxide (P = 0.022), and gastric luminal minus arterial partial pressure of carbon dioxide gap (P = 0.013). In contrast, arterial base excess (P > 0.4) and routinely measured hemodynamic variables (e.g., heart rate, blood pressure) were either less predictive compared with Tonocap-derived variables or not predictive. Conclusions Despite a low mortality rate, patients undergoing cardiac surgery exhibited high incidences of prolonged hospitalization and postoperative morbidity. The Tonocap was easy to use, particularly compared with saline tonometry. Several Tonocap-derived variables were predictive of postoperative complications consistent with previously published data using saline tonometry.

Download Full-text

Changes in arterial partial pressure and end-expired pressure of carbon dioxide in prepubescent and adult bitches undergoing ovariohysterectomy by videolaparoscopy or conventional laparotomy

Ciência Rural ◽

10.1590/0103-8478cr20170769 ◽

2018 ◽

Vol 48 (10) ◽

Author(s):

Luciana Branquinho Queiroga ◽

Gabriela Marques Sessegolo ◽

Fabiane Reginatto dos Santos ◽

Letícia Mendes Fratini ◽

Verônica Santos Mombach ◽

...

Keyword(s):

Carbon Dioxide ◽

Partial Pressure ◽

Postoperative Period ◽

Base Excess ◽

Mild Hypertension ◽

Peak Inspiratory Pressure ◽

Arterial Partial Pressure ◽

Significant Difference ◽

The Difference ◽

Age Range

ABSTRACT: This paper aimed to determine arterial partial pressure of carbon dioxide (PaCO2), end-expired CO2 pressure (ETCO2), and the difference between arterial and end-expired CO2 pressure (Pa - ETCO2) in prepubescent and adult bitches undergoing videolaparoscopic or conventional ovariohyterectomy (OH). Forty bitches were randomly assigned to four groups: Conventional Adult (CA), Conventional Pediatric (CP), Videolaparoscopic Adult (VA) and Videolaparoscopic Pediatric (VP). Pulse rate (PR), respiratory rate (RR), systolic, mean, and diastolic arterial pressures (SAP, MAP, DAP), ETCO2, peak inspiratory pressure (PIP), pH, arterial partial pressure of oxygen (PaO2), PaCO2, base excess (BE) and HCO3 - were measured. Based on the PaCO2 and ETCO2 values, Pa-ETCO2 was determined. There was no significant difference in PaCO2 between the VA (42.5±5.2 to 53.7±5.2) and VP (48.4±5.4 to55.4±5.7) groups. During the postoperative period, all groups presented with hypertension. However, mild hypertension (SAP 150 to 159mmHg) was observed in the VP group as compared to severe hypertension (SAP>180mmHg) in the CA group, suggesting that both the age range and videolaparoscopic OH are associated with lower levels of hypertension during the postoperative period in dogs.

Download Full-text