Practical experiences and in vitro and in vivo validation studies with a new gastric tonometric probe in human adult patients

PURPOSE: This study provides practical experiences with a new, simple, balloon-free gastric tonometric probe (probe) and reports the results of simultaneous in vitro and in vivo measurements with a conventional, ballooned gastric air tonometer (catheter) and the new device. MATERIALS AND METHODS: Ten healthy volunteers and 50 anesthetized surgical patients with different American Society of Anesthesiologists (ASA) scores, scheduled for neurologic, orthopedic, trauma, and cardiac operations, were enrolled in the study. The values of 60 in vitro and, in 12 surgical patients, 101 in vivo paired Pco(2) measurements--performed simultaneously with the new tonometric probe and the catheter that was connected to a Tonocap monitor--were compared. The tolerability of the measurement with the new probe was examined, and the results of gastric tonometry and, in surgical cases, the gastric tonometric, end-expiratory, and arterial Pco(2) values were registered. The results were evaluated by analysis of variance test. The data of the in vivo paired measurements were evaluated by Bland-Altman analysis. RESULTS: The use of the probe proved to be well tolerated and easily applicable in the studied cases. The results of 20 measurements obtained in healthy volunteers and those of 520 measurements in the surgical cases correspond to the data obtained with the classical methods published in the medical literature. During in vitro paired measurements, there was a good agreement between the data obtained with the 2 methods; however, in the in vivo studies, the results of measurements performed with the probe were mostly higher. CONCLUSIONS: The differences between the results obtained with the 2 methods might have been caused by the quicker equilibration property of the probe and by the fundamental differences between the 2 methods. The new probe seems to be applicable for routine human measurements

The length of stay in the post-anaesthesia care unit correlates with pain intensity, nausea and vomiting on arrival

BACKGROUND: The benefit of the post-anaesthesia care unit (PACU) with respect to an early detection of postoperative complications is beyond dispute. From a patient perspective, prevention and optimal management of pain, nausea and vomiting (PONV) are also of utmost importance. The aims of the study were therefore to prospectively measure pain and PONV on arrival to the PACU and before discharge and to determine the relationship of pain and PONV to the length of stay in the PACU. METHODS: Postoperative pain was assessed over 30 months using a numeric rating scale on admittance to the PACU and before discharge; in addition, PONV was recorded. Statistical analysis was done considering gender, age, American Society of Anesthesiologists (ASA) classification, surgical speciality, anaesthesia technique, duration of anaesthesia, intensity of nursing and length of stay. RESULTS: Data of 12,179 patients were available for analysis. The average length of stay in the PACU was 5.7 ± 5.9 h, whereas regular PACU patients stayed for 3.2 ± 1.9 h and more complex IMC patients stayed for 15.1 ± 6.0 h. On admittance, 27% of patients were in pain and the number decreased to 13% before discharge; 3% experienced PONV. Risk factors for increased pain determined by multivariate analysis were female gender; higher ASA classification; general, cardiac and orthopaedic surgery and prolonged case duration. In more complex IMC patients, pain scores were higher on arrival but dropped to similar levels before discharge compared to regular PACU patients. Female gender and postoperative pain were risk factors for postoperative vomiting. Pain and PONV on arrival correlated with length of stay in the PACU. Pain- or PONV-free patients stayed almost half of the time in the PACU compared to patients with severe pain or vomiting on arrival. CONCLUSIONS: The majority of PACU patients had good pain control, both on admittance and before discharge, and the overall incidence of PONV was low. Managing patients in the PACU could achieve a significant reduction of pain and PONV. The level of pain and presence of PONV on admittance to the PACU correlate with and act as predictors for increased length of PACU stay