Goal-directed fluid therapy using uncalibrated pulse contour analysis and balanced crystalloid solutions during hip revision arthroplasty: a quality implementation project.

BACKGROUND: To implement a goal-directed fluid therapy (GDFT) protocol using crystalloids in hip revision arthroplasty surgery within a quality management project at a tertiary hospital using a monocentric, prospective observational study. METHODS: Adult patients scheduled for elective hip revision arthroplasty surgery were screened for inclusion in this prospective study. Intraoperatively stroke volume (SV) was optimized within a previously published protocol using uncalibrated pulse contour analysis and balanced crystalloids. Quality of perioperative GDFT was assessed by protocol adherence, SV increase as well as the rate of perioperative complications. Findings were then compared to two different historical groups of a former trial: one receiving GDFT with colloids (prospective colloid group) and one standard fluid therapy (retrospective control group) throughout surgery. Statistical analysis constitutes exploratory data analyses and results are expressed as median with 25th and 75th percentiles, absolute and relative frequencies, and complication rates are further given with 95% confidence intervals for proportions using the normal approximation without continuity correction. RESULTS: Sixty-six patients underwent GDFT using balanced crystalloids and were compared to 130 patients with GDFT using balanced colloids and 130 controls without GDFT fluid resuscitation. There was a comparable increase in SV (crystalloids: 65 (54-74 ml; colloids: 67.5 (60-75.25 ml) and total volume infused (crystalloids: 2575 (2000-4210) ml; colloids: 2435 (1760-3480) ml; and controls: 2210 (1658-3000) ml). Overall perioperative complications rates were similar (42.4% (95%CI 30.3-55.2%) for crystalloids and 49.2% (95%CI 40.4-58.1%) for colloids and lower compared to controls: 66.9% (95%CI 58.1-74.9)). Interestingly, a reduced number of hemorrhagic complications was observed within crystalloids: 30% (95%CI 19.6-42.9); colloids: 43% (95%CI 34.4-52.0); and controls: 62% (95%CI 52.6-69.9). There were no differences in the rate of admission to the post-anesthesia care unit or intensive care unit as well as the length of stay. CONCLUSIONS: Perioperative fluid management using a GDFT protocol with crystalloids in hip revision arthroplasty surgery was successfully implemented in daily clinical routine. Perioperative complications rates were reduced compared to a previous management without GDFT and comparable when using colloids. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01753050.

Ultrastructural changes associated with myocardial apoptosis, in failing rat hearts induced by volume overload.

BACKGROUND: Myocardial apoptosis has been discussed to play a pivotal role in the development and progression of congestive heart failure (CHF). However, recently there is doubt on the evidence of myocardial apoptosis in heart failure as information on ultrastructural changes by electron microscopy is still scarce. This project therefore aimed to detect direct morphological evidence of myocardial apoptosis in an experimental heart failure model. METHOD: Following IRB approval, an aortocaval fistula (ACF) was induced in male Wistar rats using a 16G needle. 28±2days following ACF rats were examined by hemodynamic measurements, Western blot, immunofluorescence confocal and electron microscopic analysis. RESULTS: Within 28±2days of ACF heart (3.8±0.1 vs. 6.6±0.3mg/g) and lung (3.7±0.2 vs. 6.9±0.5mg/g) weight indices significantly increased in the ACF group accompanied by a restriction in systolic (LVEF: 72±2 vs. 39±3%) and diastolic (dP/dtmin.: -10,435±942 vs. -5982±745mmHg/s) function (p<0.01). Activated caspase-3 was significantly increased in failing hearts concomitant with mitochondrial leakage of cytochrome c into the cytosol. Finally, electron microscopy of the left ventricle (LV) of ACF rats revealed pronounced ultrastructural changes in >70% of examined cardiomyocytes, such as nuclear chromatin condensation, myofibril loss and disarray, contour irregularities and amorphous dense bodies, mitochondriosis and damaged cell-cell-contacts between cardiomyocytes. CONCLUSIONS: Volume overload induced heart failure is associated with activation of the mitochondrial apoptotic pathway. In addition, electron microscopy of the LV revealed direct ultrastructural evidence of extended myocardial apoptosis in ACF rats.