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

Bennett‐Guerrero, Elliott; Panah, Michael; Bodian, Carol; Methikalam, Blessy J.; Alfarone, John R.; DePerio, Marietta; Mythen, Michael G.

doi:10.1097/00000542-200001000-00012

Cited by 78 publications

(45 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Anaesthesia was induced using fentanyl 400 lg, thiopental 200 mg, and neuromuscular blockade was produced using pancuronium 7 mg. Anaesthesia was maintained using isoflurane and fentanyl. Propofol (2)(3)(4)(5) , the aorta was cross-clamped and a cold crystalloid cardioplegic solution was injected. The arterial perfusion pressure was kept between 50 and 70 mmHg using phenylephrine if necessary.…”

Section: Patientsmentioning

confidence: 99%

Rectal lactate levels in endoluminal microdialysate during routine coronary surgery*

et al. 2007

View full text Add to dashboard Cite

SummaryThe aim of this prospective study was to determine the feasibility of intestinal endoluminal microdialysis as a new method for clinical monitoring of the adequacy of splanchnic perfusion in the large bowel. A microdialysis catheter for continuous lactate, glycerol, glucose and pyruvate measurements attached to a tonometric catheter was placed into the lumen of the recto-sigmoid junction prior to surgery in 13 patients undergoing elective cardiac surgery with cardiopulmonary bypass (CPB). Lactate was also measured in blood and muscle. CPB was associated with a 10-fold increase in luminal lactate from 0.16 (0.01) to 1.67 (0.38) mmol.l )1 (p < 0.001). Muscular lactate increased from baseline levels 1.20 (0.21) to 1.77 (0.36) mmol.l )1 during CPB (p = 0.01), but the muscular lactate-pyruvate ratio remained unchanged. Arterial lactate increased only slightly from 0.9 (0.05) to 1.1 (0.06) mmol.l )1 (p = 0.027) during CPB. Increased lactate concentrations in the large bowel during CPB are suggestive of local lactate production consistent with impaired oxygen delivery. Intestinal endoluminal microdialysis is a potential clinically applicable method for monitoring intestinal metabolism. Combined with tonometry, microdialysis provides the opportunity to monitor both circulation and metabolism in the rectal mucosa. Patients undergoing cardiac surgery with cardiopulmonary bypass (CPB) are at risk of developing intestinal mucosal ischaemia, leading to disturbed mucosal integrity and increased intestinal permeability [1]. The latter may result in leakage of endotoxins into the circulation contributing to systemic inflammation observed during CPB [2]. The most likely cause of increased intestinal vascular permeability is imbalance between splanchnic oxygen supply and demand [3].There are currently few reliable methods available for monitoring adequacy of splanchnic perfusion during CPB. If available, these data could lead to strategies being developed to reduce intestinal ischaemia and the resulting increased mucosal permeability. Gastric tonometry is the only clinically available method that allows monitoring of gastro-intestinal perfusion. Even though in cardiac [4,5] and high-risk surgical patients [6] peri-operative tonometry-derived variables are predictive

show abstract

Section: Patientsmentioning

confidence: 99%

Rectal lactate levels in endoluminal microdialysate during routine coronary surgery*

et al. 2007

View full text Add to dashboard Cite

show abstract

“…It is valuable as a prognostic tool and to detect hypovolemia before it can be identified by global hemodynamic variables. 2,7 Until now, the experience with gastric tonometry in children is limited. 8,9 However, due to its minimal invasiveness and ease of use, gastric air tonometry may become an interesting monitor in a group of patients in whom central venous and pulmonary artery catheterization is not always easy or feasible.…”

Section: Méthodementioning

confidence: 99%

“…1 The introduction of automated air tonometry has facilitated measurement of gastric mucosal PrCO 2 in the clinical setting. 2,3 The automated air tonometer (Tonocap®, Datex-Engstrom, Tonometrics Division, Helsinki, Finland) allows periodic assessment of gastric or sigmoid PrCO 2 with the established tonometry catheters. The automated air tonometer fills the tonometer balloon with air.…”

mentioning

confidence: 99%

Nitrous oxide does not affect automated air tonometry in children

Weiß

Gerber

Dullenkopf

2003

Can J Anesth/J Can Anesth

View full text Add to dashboard Cite

P Pu ur rp po os se e: : To evaluate the effects of nitrous oxide on automated air tonometry in the clinical setting.M Ma at te er ri ia al l a an nd d m me et th ho od ds s: : With approval of the Hospital Ethical Committee and after obtaining informed parental consent, an 8-F tonometry catheter was inserted orogastrically in ten children aged one to three years scheduled for elective surgery with combined regional and general anesthesia. A standardized general anesthesia technique with tracheal intubation was used in all patients and consisted of sevoflurane in oxygen/nitrous oxide (30%/70%; n = 5 patients) or in oxygen/air (FIO 2 0.3; n = 5 patients). After obtaining steady state gastric CO 2 values (PrCO 2 ), fresh gas mixtures were rapidly changed from oxygen/nitrous oxide to oxygen/air (A) or vice versa (B). In addition, balloon pressures were recorded using a pressure transducer. Measurements were performed at intervals of ten minutes with recording of balloon pressures, end-tidal CO 2 (PETCO 2 ) and PrCO 2 values. Pr-ETCO 2 -gap were calculated to eliminate influences of changes in PaCO 2 .R Re es su ul lt ts s: : Changing the fresh gas mixture from N 2 O/O 2 to O 2 /air resulted in a decrease of balloon pressure of -10.4% (113.4 ± 14.7 mmHg to 101.6 ± 25.0 mmHg). Changing the fresh gas mixture from O 2 /air to N 2 O/O 2 resulted in an increase of balloon pressures of 6.4% (107.6 ± 19.3 mmHg to 114.0 ± 20.3 mmHg). During both fresh gas exchange experiments no significant changes (> 0.2 kPa) in calculated Pr-ETCO 2 -gaps were observed. C Co on nc cl lu us si io on ns s: : Based on our in vivo data, nitrous oxide during general anesthesia can be used with automated air tonometry and does not affect air tonometric PrCO 2 reading in clinical practice. 4 % (113,4 ± 14,7 mmHg à 101,6 ± 25,0 6,4 % (107,6 ± 19,3 mmHg à 114,0 ± 20,3 mmHg Objectif mmHg). Le remplacement de O 2 /air à N 2 O/O 2 a provoqué une augmentation des pressions du ballonnet de

show abstract

“…Partial pressure of carbon dioxide in the gastric lumen (regional PCO 2 = P r CO 2 ) can be used as a non-invasive method for assessing adequacy of gut mucosal perfusion [1]. The P r CO 2 value represents the balance between CO 2 production and its removal by gastrointestinal mucosal perfusion and alveolar ventilation [2].The introduction of automated air tonometry has significantly facilitated the measurement of gastric mucosal P r CO 2 in the clinical setting [3,4]. The automated air tonometer (TONOCAP Ò , Datex-Engstrom, Tonometrics Division, Helsinki, Finland) allows semi-continuous periodic assessment of gastric or sigmoid P r CO 2 with compatible tonometry catheters.…”

mentioning

confidence: 99%

“…Following an equilibration period of 10 min, the air is automatically sampled and analysed for CO 2 by means of an infrared sensor. In order to avoid depletion of luminal CO 2 and to reduce equilibration times, the aspirated gas mixture is re-filled into the sampling balloon [5].There is an increasing interest in assessment of gastric luminal P r CO 2 during cardiac surgery with hypothermic cardio-pulmonary bypass [6][7][8]. Thus the aim of the present study was to evaluate performance of automated air tonometric assessment of P r CO 2 during normo-and hypothermia using the TONOCAP Ò in an in vitro set-up.…”

mentioning

confidence: 99%

Performance of automated air tonometry under hypothermia

Weiß¹,

Dullenkopf²,

Hasenclever

2005

Anaesthesia

View full text Add to dashboard Cite

SummaryIntestinal tonometry is used during hypothermic cardio-pulmonary bypass surgery to assess splanchnic perfusion. In an in vitro set-up the performance of automated air tonometry (TONOCAP Ò ) was tested for normo-and hypothermia. A 14-FG tonometry catheter was built into a testing chamber (100 cm 3 ) perfused with blood from a cardio-pulmonary bypass circuit with P a CO 2 held at 5.6-5.8 kPa (alphastat). P r CO 2 from the balloon of the tonometry catheter was measured at intervals of 10 min at 37°C and at 25°C by the TONOCAP Ò . Bias (precision) of P r CO 2 -P a CO 2 alpha-stat and P r CO 2 ) P a CO 2 pH-stat at 37°C blood temperature were low at 0.23 kPa (0.21) each. Tonometrically measured P r CO 2 at 25°C significantly differed from P a CO 2 alpha-stat bias (precision) of 2.00 kPa (0.11) but was similar to P a CO 2 pH-stat (0.30 kPa (0.11)). P r CO 2 values as measured by the TONOCAP Ò represent pH-stat approach. Identical blood gas management (pH-or alpha-stat) should be used for calculation of mucosal -arterial CO 2 difference (P r-a CO 2 gap) or calculation of intramucosal pH. Partial pressure of carbon dioxide in the gastric lumen (regional PCO 2 = P r CO 2 ) can be used as a non-invasive method for assessing adequacy of gut mucosal perfusion [1]. The P r CO 2 value represents the balance between CO 2 production and its removal by gastrointestinal mucosal perfusion and alveolar ventilation [2].The introduction of automated air tonometry has significantly facilitated the measurement of gastric mucosal P r CO 2 in the clinical setting [3,4]. The automated air tonometer (TONOCAP Ò , Datex-Engstrom, Tonometrics Division, Helsinki, Finland) allows semi-continuous periodic assessment of gastric or sigmoid P r CO 2 with compatible tonometry catheters. The automated air tonometer fills the balloon at the distal end of the tonometry catheter with air. Following an equilibration period of 10 min, the air is automatically sampled and analysed for CO 2 by means of an infrared sensor. In order to avoid depletion of luminal CO 2 and to reduce equilibration times, the aspirated gas mixture is re-filled into the sampling balloon [5].There is an increasing interest in assessment of gastric luminal P r CO 2 during cardiac surgery with hypothermic cardio-pulmonary bypass [6][7][8]. Thus the aim of the present study was to evaluate performance of automated air tonometric assessment of P r CO 2 during normo-and hypothermia using the TONOCAP Ò in an in vitro set-up. Materials and methods

show abstract

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

Cited by 78 publications

References 13 publications

Rectal lactate levels in endoluminal microdialysate during routine coronary surgery*

Rectal lactate levels in endoluminal microdialysate during routine coronary surgery*

Nitrous oxide does not affect automated air tonometry in children

Performance of automated air tonometry under hypothermia

Contact Info

Product

Resources

About