Application of Data Science to Quantify the Effect of Propofol Infusion on Postoperative Nausea and Vomiting.

The effectiveness of propofol infusion on postoperative nausea and vomiting (PONV) is poorly understood in relation to various patient and procedure characteristics. This retrospective cohort study aimed to quantify the effectiveness of propofol infusion when administered either via total intravenous administration (TIVA) or combined intravenous anesthesia (CIVA) with inhalational agents on PONV. The relationship between propofol infusion and PONV was characterized controlling for patient demographics, procedure characteristics, PONV risk factors, and antiemetic drugs in adult patients (age ≥18 years) undergoing general anesthesia. Learned coefficients from multivariate regression models were reported as "lift" which represents the percentage change in the base likelihood of observing PONV if a variable is present versus absent. In a total of 41,490 patients, models showed that propofol infusion has a naive effect on PONV with a lift of -41% (P < .001) when using TIVA and -17% (P < .001) when using CIVA. Adding interaction terms to the model resulted in the loss of statistical significance in these relationships (lift of -30%, P = .23, when using TIVA, and -42%, P = .36, when using CIVA). It was further found that CIVA/TIVA are ineffective in short cases (CIVA * short surgery duration: lift = 49%, P < .001 and TIVA * short surgery duration: lift = 56%, P < .001).

A Case Report of Severe Factor XI Deficiency during Cardiac Surgery: Less Can Be More.

Severe congenital Factor XI (FXI) deficiency (<20% normal activity) can be associated with significant bleeding disorders, and there has been great concern for severe bleeding following cardiac surgery requiring cardiopulmonary bypass (CPB) in this patient population. Over the past four decades remarkably different approaches to this problem have been taken, including the administration of blood volumes of fresh frozen plasma, administration of activated recombinant Factor VII, and diminutive administration of heparin. We describe a case wherein the patient was assessed in the perioperative period with a point-of-care, viscoelastic hemostasis device (ROTEM), with changes in the intrinsic/Factor XII-dependent coagulation pathway determined before, during, and after CPB. Fresh frozen plasma was administered in small amounts (5−7.5 mL/kg) just before surgery began and just before cessation of CPB. Administering fresh frozen plasma to the patient to nearly normalize in vitro ROTEM hemostasis values at times when hemostasis was needed resulted in no important bleeding occurring or need of further transfusion of other blood products. In conclusion, by using small amounts of fresh frozen plasma guided by ROTEM, an evidenced-based, precision medicine approach resulted in optimized patient care and outcome.

Central fixation element type and length affect glenoid baseplate micromotion in reverse shoulder arthroplasty.

BACKGROUND: Reverse shoulder arthroplasty (RSA) is commonly used to treat patients with rotator cuff tear arthropathy. Loosening of the glenoid component remains one of the principal modes of failure and represents a significant complication that requires revision surgery. This study assessed the effects of various factors on glenoid baseplate micromotion for primary fixation of RSA. MATERIALS AND METHODS: A half-fractional factorial design of experiment was used to assess 4 factors: central element type (central peg or screw), central cortical engagement according to length (13.5 or 23.5 mm), anterior-posterior peripheral screw type (nonlocking or locking), and cancellous bone surrogate density (160 or 400 kg/m3, 10 or 25 PCF). Glenoid baseplates were implanted into high- or low-density Sawbones rigid polyurethane foam blocks and cyclically loaded at 60° for 1000 cycles (500-N compressive force range) using a custom-designed loading apparatus. Micromotion at the 4 peripheral screw positions was recorded using linear variable differential transformers. RESULTS: Central peg fixation generated 358% greater micromotion at all peripheral screw positions compared with central screw fixation (P < .001). Baseplates with short central elements that lacked cortical bone engagement generated 328% greater micromotion than those with long central elements (P = .001). No significant effects were observed when varying anterior-posterior peripheral screw type or bone surrogate density. There were significant interactions between central element type and length (P < .001). DISCUSSION: A central screw and a long central element that engaged cortical bone reduced RSA baseplate micromotion. These findings serve to inform surgical decision making regarding baseplate fixation elements to minimize the risk of glenoid loosening and, thus, the need for revision surgery.