Transcutaneous CO2 and O2 diffusion.

E Berardesca; H Maibach

Home/Archive/PubMed

PubMed · 8489772

Transcutaneous CO2 and O2 diffusion.

E Berardesca·H Maibach

View original source ↗Export metadata ↓

Abstract

Transcutaneous gas measurements offer a useful tool for non-invasive monitoring of skin function, but are affected by several variables that restrict their use in clinical and investigative dermatology. Skin thickness, stratum corneum and barrier function damage, blood vessel reactivity, arterial-gas concentration, skin and environmental temperature are important factors influencing transcutaneous gas flux. Improvement of techniques and standardization of methods with guidelines for operators should improve this interesting research approach.

Explore related subjects

Blood Gas Monitoring, Transcutaneous Carbon Dioxide Humans Keratinocytes Oxygen Skin Skin Physiological Phenomena Journal Article Review

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

E Berardesca, H Maibach. 1993. Transcutaneous CO2 and O2 diffusion.. https://pubmed.ncbi.nlm.nih.gov/8489772/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed1996

Transcutaneous oxygen (TcPO2) estimates probability of healing in the ischemic extremity.

The severity of arterial ischemia is a major variable affecting healing of extremity wounds. By relating risk of failure to severity of ischemia, the probability of wound healing may be stratified along with assessment of general medical risks. Transcutaneous oxygen tension (TcPO2) arterial segmental pressure (ASP), and arterial segmental indices (ASI) were obtained in 204 ischemic lower extremity sites; 63% of the sites were in patients with diabetes mellitus (DM), 11% in patients with chronic renal failure (CRF), and 37% in patients with neither DM nor CRF (ND). Wounds included 126 amputations and 78 gangrenous ulcerations of the foot or toes. Healing (n = 112) was defined as complete wound closure, without regard to the time required. Failure (n = 92) was defined by the requirement for either arterial reconstruction (n = 45) or proximal amputation (n = 47). Stepwise multiple regression analysis was used to assess the relative contribution of each measurement and to predict the probability of healing; TcP02 was superior to ASP and ASI in all categories. TcP02 was the only test meeting the P < 0.05 entry criteria modeled by the regression. An accuracy of 83% was achieved. However, when each test was evaluated by univariate analysis, ASP and ASI did meet the criteria for the ND group. However, the accuracy was 68 and 72%, respectively. Predictive accuracy of TcP02 was unaffected by DM or CRF. ASP and ASI were satisfactory in the ND group, although of slightly reduced accuracy. ASP and ASI were misleading and inaccurate in DM and CRF. Thus, of the noninvasive tests, TcP02 alone is sufficient for objective risk stratification of arterial ischemia in the lower extremity.

Blood Gas Monitoring, Transcutaneous↗

PubMed1996

Functional microcirculatory impairment: a possible source of reduced skin oxygen tension in human diabetes mellitus.

Lower extremity transcutaneous oxygen tension (TcPO2) is used in diagnostic and prognostic indicator of tissue perfusion and is reduced in diabetes mellitus. Since cardiac output, leg blood flow and microvascular perfusion each can singly or jointly effect tissue oxygenation, the relative importance of macro- vs microvascular factors has not been resolved. To clarify this issue we compared TcPO2 levels in diabetic and nondiabetic subjects in whom cardiac output, leg pulsatile blood flow, and microcirculatory perfusion parameters were noninvasively measured. In 60 diabetic and 60 nondiabetic subjects the following measurements were done on both legs during a single session evaluation: foot dorsum TcPO2 at 45 degrees using laser-Doppler, ankle-brachial index using Doppler ultrasound (ABI), and pulsatile leg blood flow using magnetic resonance flowmetry; cardiac output was determined using transthoracic bioimpedance. The diabetic and nondiabetic groups were determined to have nonsignificant differences (mean +/- SEM, DM vs NODM) with respect to age (63.3 +/- 1.1 vs 60.1 +/- 1.5 years), cardiac output (5.5 +/- 0.2 vs 5.5 +/- 0.2 l/min), leg blood flow (1.6 +/- 0.05 vs 1.7 +/- 0.06 ml/min/100 cc) and ABI. Although macrocirculatory values were equivalent, microvascular function indicators were significantly reduced in the diabetic group: TcPO2 (51.9 +/- 1.4 vs 62.9 +/- 1.3 mmHg); MVR 76.7 +/- 1.5 vs 84.9 +/- 0.9%) and were correlated only in diabetics (r2 = 0.48, P < 0.001). The findings suggest a primary linkage between the diabetic TcPO2 deficit and the microcirculatory submaximal vasodilatory response, with little if any role of macrocirculatory factors.

Blood Gas Monitoring, Transcutaneous↗

PubMed1996

Long-term transcutaneous monitoring of oxygen tension and carbon dioxide at 42 degrees C in critically ill neonates: improved performance of the tcpo2 monitor with topical metabolic inhibition.

UNLABELLED: Whereas during the last few years handling of the transcutaneous PO2 (tcPO2) and PCO2 (tcPCO2) sensor has been simplified, the high electrode temperature and the short application time remain major drawbacks. In order to determine whether the application of a topical metabolic inhibitor allows reliable measurement at a sensor temperature of 42 degrees C for a period of up to 12 h, we performed a prospective, open, nonrandomized study in a sequential sample of 20 critically ill neonates. A total of 120 comparisons (six repeated measurements per patient) between arterial and transcutaneous values were obtained. Transcutaneous values were measured with a control sensor at 44 degrees C (conventional contact medium, average application time 3 h) and a test sensor at 42 degrees C (Eugenol solution, average application time 8 h). Comparison of tcPO2 and PaO2 at 42 degrees C (Eugenol solution) showed a mean difference of +0.16 kPa (range +1.60 to -2.00 kPa), limits of agreement +1.88 and -1.56 kPa. Comparison of tcPO2 and PaO2 at 44 degrees C (control sensor) revealed a mean difference of +0.02 kPa (range +2.60 to -1.90 kPa), limits of agreement +2.12 and -2.08 kPa. Comparison of tcPCO2 and PaCO2 at 42 degrees C (Eugenol solution) showed a mean difference of +0.91 (range +2.30 to +0.10 kPa), limits of agreement +2.24 and -0.42 kPa. Comparison of tcPCO2 and PaCO2 at 44 degrees C (control sensor) revealed a mean difference of +0.63 kPa (range 1.50 to -0.30 kPa), limits of agreement +1.73 and -0.47 kPa. CONCLUSION: Our results show that the use of an Eugenol solution allows reliable measurement of tcPO2 at a heating temperature of 42 degrees C; the application time can be prolongued up to a maximum of 12 h without aggravating the skin lesions. The performance of the tcPCO2 monitor was slightly worse at 42 degrees C than at 44 degrees C suggesting that for the Eugenol solution the metabolic offset should be corrected.

Blood Gas Monitoring, Transcutaneous↗