Central Venous Pressure Drop After Hypovolemic Phlebotomy is a Strong Independent Predictor of Intraoperative Blood Loss During Liver Resection.

BACKGROUND: Intraoperative hypovolemic phlebotomy (HP) has been suggested to reduce central venous pressure (CVP) before hepatectomy. This study aimed to analyze the impact of CVP drop after HP on intraoperative blood loss and postoperative renal function. METHODS: A retrospective review of a prospective database including 100 consecutive patients (43 males and 57 females; mean age, 65 years; range 23-89 years) undergoing liver resection with HP was performed. The primary outcome variable was estimated blood loss (EBL), and the secondary outcome was postoperative serum creatinin (Scr). A multivariate linear regression analysis was performed to identify predictors of intraoperative blood loss. RESULTS: The median CVP before blood salvage was 8 mmHg (range 4-30 mmHg). The median volume of hypovolemic phlebotomy was 400 ml (range 200-1000 ml). After HP, CVP decreased to a median of 3 mmHg (range -2 to 16 mmHg), resulting in a median CVP drop of 5.5 mmHg (range 2-14 mmHg). The median EBL during liver resection was 165 ml (range 0-800 ml). The median preoperative serum creatinin (Scr) was 0.82 g/dl (range 0.5-1.74 g/dl), and the postoperative Scr on day 1 was 0.74 g/dl (range 0.44-1.68 g/dl). The CVP drop was associated with EBL (P < 0.001). There was no significant impact of CVP drop on postoperative Scr. CONCLUSION: A CVP drop after HP is a strong independent predictor of EBL during liver resection. The authors advocate the routine use of HP to reduce perioperative blood loss and transfusion rates in liver surgery. As a predictive tool, CVP drop might help surgeons decide whether a laparoscopic approach is safe.

Non-invasive Quantification of Fat Deposits in Skeletal Muscle Predicts Cardiovascular Outcome in Kidney Failure.

Fat accumulation in skeletal muscle was recently established as a major risk factor for cardiovascular disease (CVD) in the general population, but its relevance for patients with kidney failure is unknown. Here we examined the potential association between muscle radiation attenuation (MRA), a non-invasive indicator of fat deposits in muscle, and cardiovascular events in patients with kidney failure treated with peritoneal dialysis (PD) and investigated dynamic changes and determinants of MRA in this population. We retrospectively assessed MRA on computed tomography images collected yearly in 101 incident patients with kidney failure starting PD between January 2006 and December 2015. After a median of 21 months on dialysis, 34 patients had 58 non-fatal cardiovascular events, and 22 patients had died. Baseline MRA was associated with cardiovascular events during time on dialysis, and patients with higher MRA (reflecting lower amounts of fat in muscle) showed a reduced incidence of CVD, independently of traditional risk factors (adjusted HR, 0.91; 95% CI, 0.86-0.97, P = 0.006). Multivariate regression analysis identified old age, female gender, visceral fat area, and low residual urine volume as independent determinants of MRA. As compared with reference values from a healthy population, patients with kidney failure had lower MRA (i.e., increased fat accumulation), independently of age, gender, and body-mass index. The subset of patients who underwent kidney transplantation showed a significant increase in MRA after restoration of kidney function. These observations expand the association between ectopic fat accumulation and CVD to the population on dialysis, and suggest that kidney failure is reversibly associated with fatty muscle infiltration.