The correlation between body mass index, limb circumferences and blood pressure cuff fit in bariatric surgical patients.

INTRODUCTION: The purpose of this study was to determine the correlation between body mass index (BMI) and upper and lower arm as well as lower leg circumferences and the frequency of correct blood pressure (BP) cuff fit. We explored recommendations for the most likely BP cuff size and location for the three BMI categories. MATERIALS AND METHODS: Following IRB approval we retrospectively analyzed a research database of bariatric surgical patients with a BMI of ≥40 kg/m(2). Data included patients' characteristics, upper and lower arm as well as lower leg circumferences. Patients were divided into three groups based on BMI (kg/m(2), Group I: <45, Group II: 45-55, and Group III: >55). Appropriate cuff fit using a standard or large adult BP cuff (CRITIKON(®), GE Healthcare, Waukesha, Wisconsin, USA) on the upper and lower arm, and lower leg was determined. We analyzed the percent proportion of proper cuff fit for cuff sizes and locations between groups using appropriate nonparametric testing. RESULTS: Limb circumference correlated significantly with BMI (P = 0.01), and the upper arm correlated most closely (r = 0.76). A standard adult BP cuff on the lower arm fit properly in >90% and >80% and in Groups I and II, respectively. A large cuff on the lower arm was appropriate in 87% of Group III. In two participants, a large cuff fit properly on the lower leg. DISCUSSION: Limb circumference significantly correlated with BMI. Recommendations for proper cuff fit in different BMI categories can be made.

The volume and pH of residual pharyngeal fluid aspirated from the TaperGuard Evac™ Endotracheal Tube following elective surgery: a prospective pilot study.

BACKGROUND: Oropharyngeal suctioning prior to extubation aims to minimize postextubation tracheal soiling from remaining fluid. We investigated the amount and nature of any fluid remaining after such suctioning and contributing factors. METHODS: ASA I - III patients undergoing elective surgery under general anesthesia with endotracheal intubation participated in this prospective observational pilot study. Following oropharyngeal suctioning immediately prior to extubation, a dedicated port of the endotracheal tube (TaperGuard Evac™ Endotracheal Tube) was aspirated. The amount and pH of residual fluid was recorded. Data collection included age, sex, body mass index, comorbidities, ASA status, procedure type and duration. The Chi-Square, Wilcoxon Rank-Sum, t-tests, and univariate regression analysis were used as appropriate. RESULTS: Ninety-eight patients completed the study. The mean aspirated volume in 38 (38.8%) patients was 0.9 ± 1.3 mL and sixty patients (61.2%) had no aspirate. A body mass index of ≥ 30 kg/m2 was associated with the presence of fluid (P=0.03), and a higher volume (P=0.03). The fluid pH was 7 ± 0.81 (mean ± SD). A duration of surgery ≥ 120 minutes predicted a lower pH. CONCLUSION: The prevalence and amount of residual fluid after oropharyngeal suctioning was low and likely clinically insignificant. A higher body mass index was associated with a higher incidence and volume of residual fluid. Longer procedure duration determined a slightly lower pH, with a mildly acidic pH range. The possibility of a lower fluid pH after prolonged surgery contributing to postoperative sore throat via mucosal irritation warrants investigation.

Availability of anesthetic effect monitoring: utilization, intraoperative management and time to extubation in liver transplantation.

Titration of volatile anesthetics to anesthetic effect monitoring using the bispectral index (BIS) has been shown to decrease anesthetic requirements and facilitate recovery from anesthesia unrelated to liver transplantation (OLT). To determine whether availability of such monitoring influences its utilization pattern and affect anesthetic care and outcomes in OLT, we conducted a retrospective analysis in recipients with and without such monitoring. We evaluated annual BIS utilization over a period of 7 years, and compared 41 BIS-monitored patients to 42 controls. All received an isoflurane/air/oxygen and opioid-based anesthetic with planned postoperative ventilation. Data collection included age, body mass index (BMI), gender, Model for End-stage Liver Disease (MELD) score, and time to extubation (TtE). Mean preanhepatic, anhepatic, and postanhepatic end-tidal isoflurane concentrations were compared, as well as BIS values for each phase of OLT using the Kruskal-Wallis and Wilcoxon signed-rank tests, respectively. The use of anesthetic effect monitoring when available increased steadily from 15% of cases in the first year to almost 93% by year 7. There was no significant difference in age, gender, BMI, MELD, or TtE between groups. The BIS group received less inhalational anesthetic during each phase of OLT compared to the control group. However, this difference was statistically significant only during the anhepatic phase (P = .026), and was clinically not impressive. Within the BIS group, the mean BIS value was 38.74 ± 5.25 (mean ± standard deviation), and there was no difference for the BIS value between different transplant phases. Availability of anesthetic effect monitoring as an optional monitoring tool during OLT results in its increasing utilization by anesthesia care teams over time. However, unless integrated into an intraoperative algorithm and an early extubation protocol for fast tracking of OLT recipients, this utilization does not appear to provide a clinical benefit but instead drives cost.

Antinociceptive effects of hydromorphone, bupivacaine and biphalin released from PLGA polymer after intrathecal implantation in rats.

Intraspinal drug delivery, based on the concept of controlling pain by delivering drug to a nociceptive target rich in opioid and other relevant receptors is increasingly used clinically. The therapeutic ratio for opioids or other centrally acting agents is potentially greater if they are administered intrathecally (i.t.) than outside the central nervous system (CNS). The present study was designed with the ultimate goal of formulating a controlled release system for intrathecal analgesia characterized by effectiveness, rapid onset and few side effects for chronic pain control. A biodegradable copolymer poly(L-lactide-co-glycolide) (PLGA) was used to prepare a rod-shaped drug delivery system containing hydromorphone (HM), bupivacaine (BP), both HM and BP, or biphalin (BI). In vitro drug release kinetics of these systems showed a zero-order release rate for HM and BP from PLGA (85:15) rods. Drug-loaded rods were implanted i.t. Control groups received only placebo implants. Measurement of analgesic efficacy was carried out with tail flick and paw-withdrawal tests. In vivo studies showed potent, prolonged analgesia in comparison to controls for all active treatments. Analgesic synergy was observed with HM and BP. With further refinements of drug release rate, these rods may offer a clinically relevant alternative for intrathecal analgesia.