Gastric tonometry guided therapy in critical care patients: a systematic review and meta-analysis

Abstract

IntroductionThe value of gastric intramucosal pH (pHi) can be calculated from the tonometrically measured partial pressure of carbon dioxide () in the stomach and the arterial bicarbonate content. Low pHi and increase of the difference between gastric mucosal and arterial ( gap) reflect splanchnic hypoperfusion and are good indicators of poor prognosis. Some randomized controlled trials (RCTs) were performed based on the theory that normalizing the low pHi or gap could improve the outcomes of critical care patients. However, the conclusions of these RCTs were divergent. Therefore, we performed a systematic review and meta-analysis to assess the effects of this goal directed therapy on patient outcome in Intensive Care Units (ICUs).MethodsWe searched PubMed, EMBASE, the Cochrane Library and ClinicalTrials.gov for randomized controlled trials comparing gastric tonometry guided therapy with control groups. Baseline characteristics of each included RCT were extracted and displayed in a table. We calculated pooled odds ratios (ORs) with 95% confidence intervals (CIs) for dichotomous outcomes. Another measure of effect (risk difference, RD) was used to reassess the effects of gastric tonometry on total mortality. We performed sensitivity analysis for total mortality. Continuous outcomes were presented as standardised mean differences (SMDs) together with 95% CIs.ResultsThe gastric tonometry guided therapy significantly reduced total mortality (OR, 0.732; 95% CI, 0.536 to 0.999, P = 0.049; I2 = 0%; RD, −0.056; 95% CI, −0.109 to −0.003, P = 0.038; I2 = 0%) when compared with control groups. However, after excluding the patients with normal pHi on admission, the beneficial effects of this therapy did not exist (OR, 0.736; 95% CI 0.506 to 1.071, P = 0.109; I2 = 0%). ICU length of stay, hospital length of stay and days intubated were not significantly improved by this therapy.ConclusionsIn critical care patients, gastric tonometry guided therapy can reduce total mortality. Patients with normal pHi on admission contributed to the ultimate result of this outcome; it may indicate that these patients may be more sensitive to this therapy.

Сепсис: Традиції Та Інновації В Термінології, Патогенезі, Діагностиці, Інтенсивній Терапії — Заради Врятування Та Збереження Життя Хворого

“…Высокое соотношение P (V-A) CO 2 /C(a-v)O 2 ассоциируется со сниженным клиренсом лактата после ресусцитации. Соотно-шение P (V-A) CO 2 /C(a-v)O 2 является индикатором анаэробного метаболизма [22].…”

Best practice in critical care: anaemia in acute and critical illness

“…When the perfusion of gastric mucosa is reduced, CO 2 accumulates, and this can be used in combination with systemic bicarbonate concentrations to evaluate the adequacy of gastrointestinal mucosal perfusion (Deschamps et al, ). Trials have used this to guide inotropic/vasopressor therapy and RBC transfusion but have not found significant improvement in mortality outcomes (Zhang et al, ). The methodology of gastric tonometry has been questioned as the systemic bicarbonate concentration may not reflect the concentration in ischaemic mucosa, and as a result, few institutions use gastric tonometry in clinical practice.…”

A fiberoptic sensor for tissue carbon dioxide monitoring

“…Gastric tonometry was in routine use in intensive care units for several decades to monitor PCO2 in the wall of the gut [6]. The technique involves injecting saline or other liquid into a gas permeable balloon placed in the stomach or small intestine for several minutes to allow equilibration of carbon dioxide from the gut wall into the saline [7]. Research A significant difference between PCO2 in the withdrawn saline and arterial blood PCO2 (the 'CO2 gap') reveals poor gut circulation, a precursor to serious conditions such as sepsis, septic shock, and in more serious cases, multiple organ dysfunction syndrome and death [4].…”

“…Probes can be made small with optical fiber diameters typically between 600μm or less [7], allowing them to be inserted into patients with minimum invasiveness or discomfort. Once inserted they can be used for continuous monitoring, allowing changes in the patient's condition to be easily identified.…”