Cardiopulmonary exercise testing before liver surgery.

BACKGROUND: Cardiopulmonary exercise testing (CPET) assessed "poorer" fitness correlates with poorer outcomes in blinded studies. Whether this correlation will persist when CPET is utilized to stratify care as part of a multi-modal enhanced recovery after surgery (ERAS) program is unclear. This study examined whether CPET variables were associated with postoperative morbidity in patients undergoing hepatectomy within an ERAS program. OBJECTIVES AND METHODS: Data were prospectively collected on patients undergoing elective hepatectomy between October 2009 and April 2011. The relationships between CPET derived variables; postoperative complications and length of stay were investigated. RESULTS: Of 267 patients undergoing surgery, 197 had undergone standard cycle ergometer CPET. The relative oxygen uptake [VO2 (ml kg(-1) min(-1))] and ventilatory equivalent of CO2 (VE/VCO2) at the anaerobic threshold (AT) were not associated with complications or length of stay. Greater absolute oxygen uptake at AT [VO2 at AT (L min(-1) )] was associated with early hospital discharge [OR 2.16 (95% CI 1.18-3.96), P = 0.013] on multivariable analysis. CONCLUSIONS: When CPET is used to delineate perioperative management a low relative oxygen uptake [VO2 (ml kg(-1) min(-1) )] at the AT does not place patients at significantly higher risk of postoperative complications. This suggests CPET assessed "poor" fitness should not be used as a barrier to surgical intervention.

Enhanced recovery in the resection of colorectal liver metastases.

BACKGROUND: There is limited evidence for the use of enhanced recovery after surgery (ERAS) in patients undergoing hepatectomy, and the impact of the evolution of ERAS over time has not been examined. This study sought to evaluate the effect of an evolving ERAS program in patients undergoing hepatectomy for colorectal liver metastases (CRLM). METHODS: A multimodal ERAS program was introduced in 2/2008. Consecutive patients undergoing hepatectomy for CRLM between 2/2008 and 9/2012 were included in the study. Data were collected prospectively. Retrospective analysis compared an early ERAS cohort (2/2008-4/2010) with a later cohort with a matured ERAS program (5/2010-8/2012). RESULTS: Length of stay reduced as experience of ERAS increased (Log-rank χ(2) = 10.43, P = 0.001). Although median length of stay remained unchanged (6 days), the probability of hospitalization beyond 10 days was 25% in the early cohort compared with 7% in the later cohort. Critical care utilization reduced over time (75.5% vs. 54.7%, P < 0.0001). Complications occurred in 38.2%, with no difference in between cohorts. One postoperative death occurred in the early cohort (<0.3%). CONCLUSIONS: This study suggests that as experience of ERAS evolves, there is a progressive reduction in hospitalization and critical care admission. This is without any increase in morbidity and mortality.

Garment fit and protection from sustained +Gz acceleration with 'full-coverage' anti-G trousers.

INTRODUCTION: Garment fit may influence the effectiveness with which Full-Coverage Anti-G Trousers (FCAGT) transmit pressure to the skin surface, and hence provide protection from sustained +Gz acceleration. A search of the available literature, however, did not reveal any prior work quantifying this effect. METHODS: Three related studies were performed. In Study I, using a mannequin, garment-to-surface pressure transmission ratios were measured at various locations under normally fitted (NF) and loosely fitted (LF) FCAGT. In Study II, garment pressure-volume ratios and lung volumes were measured at +1 Gz in six men wearing FCAGT in three conditions: NF, LF, or NF with inflatable socks at 13 kPa differential pressure (NF+SOCKS). In Study III, relaxed +Gz tolerance (RGT) and ratings of perceived exertion (RPE) at +7, +8, and +9 Gz were measured in eight men wearing FCAGT in four experimental conditions: NF; LF; abdomen LF, legs NF; or abdomen NF, legs LF. RESULTS: LF did not affect pressure transmission over the lower limbs or lower abdomen, but transmission over the upper abdomen was significantly compromised. Lung volumes were reduced with FCAGT inflation, but LF was associated with greater expiratory reserve volumes and increased FCAGT volume. Under +Gz acceleration, LF over the abdomen (with or without lower limb LF) decreased RGT and increased RPE, but not with lower limb LF when abdominal fit was normal. DISCUSSION: Care should be taken to achieve and maintain a snug FCAGT fit, especially of the abdominal portion of the FCAGT, to ensure optimal anti-G protection during sustained acceleration.