BACKGROUND: Postoperative acute kidney injury (AKI) after lung transplantation (LTx) is an important factor affecting the short-term outcomes. The focus item of transplantation centers is how to improve the incidence of AKI through optimal management during the perioperative period.
OBJECTIVE: The purpose of the study is to investigate the influence of perioperative volume in the development of early AKI following LTx.
METHODS: The study involved patients who had undergone LTx between October 2018 to December 2021 at China-Japan Friendship Hospital in Beijing. The patients were monitored for AKI occurring within 72 hours after LTx, as well as the renal outcomes within 30 days. The perioperative volumes were compared and analyzed to determine the impact on various clinical outcomes.
RESULTS: 248 patients were enrolled in the study ultimately, with almost half of them (49.6 %) experiencing AKI. 48.8 % of AKI patients received continuous renal replacement therapy (CRRT), with 57.7 % recovered by the end of the 30-day follow-up period. A J-shaped relationship was demonstrated between perioperative volume and AKI incidence. Moreover, maintaining a positive fluid balance would increase the 30-day mortality and lead to poor renal outcomes.
CONCLUSIONS: Perioperative volume is an independent risk factor of early AKI after LTx. Positive fluid balance increases the risk of AKI, 30-day mortality, and adverse renal prognosis. The LTx recipients may benefit from a relatively restrict fluid strategy during and after the lung transplantation.

OBJECTIVE: Copeptin efficiently predicts post-neurosurgical central diabetes insipidus (CDI) in patients with hypothalamic-pituitary lesions, but its role in characterizing changes in diuresis in individuals with acromegaly undergoing neurosurgery remains unexplored. Our study aimed to assess changes in postoperative fluid balance in acromegaly patients and correlate them with both copeptin and growth hormone (GH) levels.
METHODS: This was a secondary analysis of a prospective study involving 15 acromegaly patients undergoing endoscopic endonasal resection at our University Hospital. Fluid balance was assessed daily, and copeptin and GH levels were evaluated preoperatively (T0), and serially on the morning of the first (T2) and second (T3) postoperative day, with an additional measurement of copeptin one hour post-extubation (T1). Patients with pre-existing or post-neurosurgical CDI were excluded from the analysis.
RESULTS: Most patients (11/15) exhibited a negative fluid balance on the second postoperative day, with 4 developing polyuria. Postoperative GH levels did not differ significantly between polyuric and non-polyuric patients, but GH measured at T2 correlated significantly with negative total balance (r = -0.519, p = 0.048). Copeptin levels at T1 were significantly higher in those who developed polyuria (p = 0.013), and a copeptin value > 39.9 pmol/L at T1 showed excellent ability (Sensitivity 100%, Specificity 90.9%, p < 0.001) in predicting postoperative polyuria. Additionally, polyuric patients exhibited a higher T1 / T3 copeptin ratio (p = 0.013) and a negative fluid balance was associated with the remission of acromegaly at 12 months (p = 0.046).
CONCLUSIONS: The early assessment of copeptin, in addition to facilitating the rapid identification of individuals at increased risk of developing CDI, could also allow the recognition of subjects with a tendency towards non-pathological polyuria in the postoperative setting, at least in individuals affected by acromegaly.

OBJECTIVE: Hypocalcemia post-metabolic bariatric surgery (MBS) is a known long-term complication after hypoabsorptive procedures. However, data on immediate postoperative calcium are limited. Our aim was to evaluate the prevalence of hypocalcemia on the 1st postoperative day after MBS and correlate it with potential associated factors.
METHODS: We analyzed data from all consecutive index MBS over 1 year. We collected data on demographics and on preoperative and postoperative values of serum calcium (TC), albumin, adjusted calcium (AC-Payne formula), magnesium, phosphorus, preoperative vitamin-D, and postoperative 24-h urine output, intravenous fluids (IVF), bolus intravenous furosemide, and creatine phosphokinase (CPK). Continuous data are expressed as means ± SD (range). Categorical data are presented as frequencies (%). Linear regression was implemented to designate potential correlations.
RESULTS: The cohort included 86 patients (58.1% females). The mean preoperative TC was 9.4mg/dL ± 0.4 (8.5-10.5) and mean postoperative TC 7.8mg/dL ± 0.6 (6.3-9.3, 17.0% decrease). The mean preoperative AC was 10.1mg/dL ± 0.4 (9.2-11.2) and mean postoperative AC 8.5mg/dL ± 0.6 (7.0-10.0, 15.8% decrease). Seventy-three patients (84.8%) had abnormally low TC (< 8.5mg/dL), and 43 (50%) abnormally low AC. There was only weak correlation between postoperative TC and AC with magnesium (r = 0.258), phosphorus (r = 0.269), vitamin-D (-0.163), 24-h urine output (r = -0.168), IVF (r = -0.237), bolus furosemide (r = 0.155), and mean operative time (r = 0.010).
CONCLUSIONS: In our cohort of patients, hypocalcemia was a real problem but we did not find any significant correlation with the examined factors. Further studies are warranted to validate our findings and investigate other potential correlations.

BACKGROUND: The distribution and elimination of infused crystalloid fluid is known to be affected by general anesthesia, but it is unclear whether changes differ depending on whether the patient is operated in the flat recumbent position, the Trendelenburg (\"legs up\") position, or the reverse Trendelenburg (\"head up\") position.
METHODS: Retrospective data on hemodilution and urine output obtained during and after infusion of 1-2 L of Ringer\'s solution over 30-60 min were collected from 61 patients undergoing surgery under general anesthesia and 106 volunteers matched with respect to the infusion volume and infusion time. Parameters describing fluid distribution in the anesthetized and awake subjects were compared by population volume kinetic analysis.
RESULTS: General anesthesia decreased the rate constant for urine output by 79% (flat recumbent), 91% (legs up) and 91% (head up), suggesting that laparoscopic surgery per se intensified the already strong anesthesia-induced fluid retention. General anesthesia also decreased the rate constant governing the return of the distributed fluid to the plasma by 32%, 15%, and 70%, respectively. These results agree with laboratory data showing a depressive effect of anesthetic drugs on lymphatic pumping, and further suggest that the \"legs up\" position facilitates lymphatic flow, whereas the \"head up\" position slows this flow. Both Trendelenburg positions increased swelling of the \"third fluid space\".
CONCLUSIONS: General anesthesia caused retention of infused fluid with preferential distribution to the extravascular space. Both Trendelenburg positions had a modifying influence on the kinetic adaptations that agreed with the gravitational forces inflicted by tilting to body.

BACKGROUND: Previously identified phenotypes of acute respiratory distress syndrome (ARDS) could not reveal the dynamic change of phenotypes over time. We aimed to identify novel clinical phenotypes in ARDS using trajectories of fluid balance, to test whether phenotypes respond differently to different treatment, and to develop a simplified model for phenotype identification.
METHODS: FACTT (conservative vs liberal fluid management) trial was classified as a development cohort, joint latent class mixed models (JLCMMs) were employed to identify trajectories of fluid balance. Heterogeneity of treatment effect (HTE) for fluid management strategy across phenotypes was investigated. We also constructed a parsimonious probabilistic model using baseline data to predict the fluid trajectories in the development cohort. The trajectory groups and the probabilistic model were externally validated in EDEN (initial trophic vs full enteral feeding) trial.
RESULTS: Using JLCMM, we identified two trajectory groups in the development cohort: Class 1 (n = 758, 76.4% of the cohort) had an early positive fluid balance, but achieved negative fluid balance rapidly, and Class 2 (n = 234, 24.6% of the cohort) was characterized by persistent positive fluid balance. Compared to Class 1 patients, patients in Class 2 had significantly higher 60-day mortality (53.5% vs. 17.8%, p < 0.001), and fewer ventilator-free days (0 vs. 20, p < 0.001). A significant HTE between phenotypes and fluid management strategies was observed in the FACTT. An 8-variables model was derived for phenotype assignment.
CONCLUSIONS: We identified and validated two novel clinical trajectories for ARDS patients, with both prognostic and predictive enrichment. The trajectories of ARDS can be identified with simple classifier models.

Postexercise hydration is fundamental to replace fluid loss from sweat. This study evaluated rehydration and gastrointestinal (GI) symptoms for each of three beverages: water (W), sports drink (SD), and skimmed, lactose-free milk (SLM) after moderate-intensity cycling in the heat. Sixteen college students completed three exercise sessions each to lose ≈2% of their body mass. They drank 150% of body mass loss of the drink assigned in randomized order; net fluid balance, diuresis, and GI symptoms were measured and followed up for 3 hr after completion of fluid intake. SLM showed higher fluid retention (∼69%) versus W (∼40%; p < .001); SD (∼56%) was not different from SLM or W (p > .05). Net fluid balance was higher for SLM (-0.26 kg) and SD (-0.42 kg) than W (-0.67 kg) after 3 hr (p < .001), resulting from a significantly lower diuresis with SLM. Reported GI disturbances were mild and showed no difference among drinks (p > .05) despite ingestion of W (1,992 ± 425 ml), SD (1,999 ± 429 ml), and SLM (1,993 ± 426 ml) in 90 min. In conclusion, SLM was more effective than W for postexercise rehydration, showing greater fluid retention for the 3-hr follow-up and presenting with low-intensity GI symptoms similar to those with W and SD. These results confirm that SLM is an effective option for hydration after exercise in the heat.

BACKGROUND: The evidence base for hydration practice in care homes is underdeveloped. High-quality research is therefore needed to determine what practices support older people with dementia in drinking sufficient fluid. However, methodological developments are needed to be able to do this.
OBJECTIVE: To highlight the methodological issues researchers encountered during a feasibility cluster, randomised controlled trial of ThinkDrink, a hydration care guide for people with dementia living in UK care homes.
CONCLUSIONS: This is a challenging area because of the complexity of recruitment, participation and data collection in care homes. Researchers must pay extra attention to rigour and quality in the design of their studies. There may be multiple challenges, so various strategies may be required.
CONCLUSIONS: It is important that researchers continue to reflect on rigorous approaches to develop evidence in a crucial area of care, despite these challenges.
CONCLUSIONS: Researchers working in complex environments face a variety of challenges to complete methodologically rigorous research. It is important for researchers to be critical of research processes and data, to mitigate and overcome these challenges.

UNASSIGNED: Enhanced Recovery After Surgery (ERAS) protocol for esophagectomy may reduce the high incidence of postoperative morbidity and mortality. The aim of this study was to assess the impact of properly conducted ERAS protocol with specific emphasis on fluid balance and opioid-sparing anesthesia (OSA) on postoperative major morbidity and mortality after esophagectomy.
UNASSIGNED: Patients undergoing elective esophagectomy for esophageal cancer at the Hospital for Digestive Surgery, University Clinical Center of Serbia, from December 2017 to March 2021, were included in this retrospective observational study. Patients were divided into two groups: the ERAS group (OSA, intraoperative goal-directed therapy, and postoperative “near-zero” fluid balance) and the control group (opioid-based anesthesia, maintenance mean blood pressure ≥ 65 mmHg, and liberal postoperative fluid management). The primary outcome was major morbidity within 30 days from surgery and 30-day and 90-day mortality. Multivariable analysis was used to examine the effect of the ERAS protocol.
UNASSIGNED: A total of 121 patients were divided into the ERAS group (69 patients) and the control group (52 patients). Patients in the ERAS group was received less fentanyl, median 300 (interquartile range (IQR), 200–1,550) mcg than in control group, median 1,100 (IQR, 650–1750) mcg, p < 0.001. Median intraoperative total infusion was lower in the ERAS group, 2000 (IQR, 1000–3,750) mL compared to control group, 3,500 (IQR, 2000–5,500) mL, p < 0.001. However, intraoperative norepinephrine infusion was more administered in the ERAS group (52.2% vs. 7.7%, p < 0.001). On postoperative day 1, median cumulative fluid balance was 2,215 (IQR, −150-5880) mL in the ERAS group vs. 4692.5 (IQR, 1770–10,060) mL in the control group, p = 0.002. After the implementation of the ERAS protocol, major morbidity was less frequent in the ERAS group than in the control group (18.8% vs. 75%, p < 0.001). There was no statistical significant difference in 30-day and 90-day mortality (p = 0.07 and p = 0.119, respectively). The probability of postoperative major morbidity and interstitial pulmonary edema were higher in control group (OR 5.637; CI95%:1.178–10.98; p = 0.030 and OR 5.955; CI95% 1.702–9.084; p < 0.001, respectively).
UNASSIGNED: A major morbidity and interstitial pulmonary edema after esophagectomy were decreased after the implementation of the ERAS protocol, without impact on overall mortality.

BACKGROUND: Although there are many reasons for extubation failure, maintaining negative or lower positive fluid balances 24 hours before extubation may be a key measure for successful extubation.
OBJECTIVE: To assess the predictive value of fluid balance before extubation and its outcome in mechanically ventilated cases in the intensive care unit (ICU).
METHODS: This retrospective cohort study involved collecting clinical data from patients undergoing mechanical ventilation in Lanzhou general adult ICU from January 2022 to December 2022. Based on extubation outcomes, the patients were divided into a successful extubation group and a failed extubation group. Their fluid balance levels 24 h before extubation were compared with analyse the predictive value of fluid balance on extubation outcomes in patients undergoing mechanical ventilation.
RESULTS: In this study, clinical data from 545 patients admitted to a general adult ICU were collected. According to the inclusion and exclusion criteria, 265 (48.6%) patients were included, of which 197 (74.3%) were successfully extubated; extubation was unsuccessful in 68 (25.7%) patients. The total intake and fluid balance levels in patients in the failed extubation group 24 h before extubation were significantly higher than those in the successful extubation group, with a median of 2679.00 (2410.44-3193.50) mL versus 2435.40 (1805.04-2957.00) mL, 831.50 (26.25-1407.94) mL versus 346.00 (-163.00-941.50) mL. Receiver operating characteristic (ROC) curve analysis showed that the optimal cut-off value for predicting extubation outcomes was 497.5 mL (sensitivity 64.7%, specificity 59.4%) for fluid balance 24 h before extubation. The area under the ROC curve was 0.627 (95% confidence interval [CI] 0.547-0.707). Based on the logistic regression model, cumulative fluid balance >497.5 mL 24 h before extubation could predict its outcomes in mechanically ventilated patients in the ICU (OR = 5.591, 95% CI [2.402-13.015], p < .05).
CONCLUSIONS: The fluid balance level 24 h before extubation was correlated with the outcome of extubation in mechanically ventilated patients in the ICU. The risk of extubation failure was higher when the fluid balance level was >497.5 mL.
CONCLUSIONS: Tracheal intubation is a crucial life support technique for many critically ill patients, and determining the appropriate time for extubation remains a challenge for clinicians. Although there are many reasons for extubation failure, acute pulmonary oedema caused by continuous positive fluid balance and volume overload is one of the main reasons for extubation failure. Therefore, it is very important to study the relationship between fluid balance and extubation outcome to improve the prognosis of patients with invasive mechanical ventilation in ICU.

Sweat rate and electrolyte losses have a large inter-individual variability. A personalized approach to hydration can overcome this issue to meet an individual\'s needs. This study aimed to investigate the effects of a personalized hydration strategy (PHS) on fluid balance and intermittent exercise performance. Twelve participants conducted 11 laboratory visits including a VO2max test and two 5-day trial arms under normothermic (NOR) or hyperthermic (HYP) environmental conditions. Each arm began with three days of familiarization exercise followed by two random exercise trials with either a PHS or a control (CON). Then, participants crossed over to the second arm for: NOR+PHS, NOR+CON, HYP+PHS, or HYP+CON. The PHS was prescribed according to the participants\' fluid and sweat sodium losses. CON drank ad libitum of commercially-available electrolyte solution. Exercise trials consisted of two phases: (1) 45 min constant workload; (2) high-intensity intermittent exercise (HIIT) until exhaustion. Fluids were only provided in phase 1. PHS had a significantly greater fluid intake (HYP+PHS: 831.7 ± 166.4 g; NOR+PHS: 734.2 ± 144.9 g) compared to CON (HYP+CON: 369.8 ± 221.7 g; NOR+CON: 272.3 ± 143.0 g), regardless of environmental conditions (p < 0.001). HYP+CON produced the lowest sweat sodium concentration (56.2 ± 9.0 mmol/L) compared to other trials (p < 0.001). HYP+PHS had a slower elevated thirst perception and a longer HIIT (765 ± 452 s) compared to HYP+CON (548 ± 283 s, p = 0.04). Thus, PHS reinforces fluid intake and successfully optimizes hydration status, regardless of environmental conditions. PHS may be or is an important factor in preventing negative physiological consequences during high-intensity exercise in the heat.