Impact of different crystalloid volume regimes on intestinal anastomotic stability. Ann Surg. 2009;249:181-185. [PMID: 19212167 DOI: 10.1097/sla.0b013e31818b73dc]

Intraoperative Fluid Balance and Perioperative Complications in Ovarian Cancer Surgery

BACKGROUND

Fluid overload and hypovolemia promote postoperative complications in patients undergoing cytoreductive surgery for ovarian cancer. In the present study, postoperative complications and anastomotic leakage were investigated before and after implementation of pulse pressure variation-guided fluid management (PPVGFM) during ovarian cancer surgery.

PATIENTS AND METHODS

A total of n = 243 patients with ovarian cancer undergoing cytoreductive surgery at the University Hospital Bonn were retrospectively evaluated. Cohort A (CA; n = 185 patients) was treated before and cohort B (CB; n = 58 patients) after implementation of PPVGFM. Both cohorts were compared regarding postoperative complications.

RESULTS

Ultrasevere complications (G4/G5) were exclusively present in CA (p = 0.0025). No difference between cohorts was observed regarding severe complications (G3-G5) (p = 0.062). Median positive fluid excess was lower in CB (p = 0.001). This was independent of tumor load [peritoneal cancer index] (p = 0.001) and FIGO stage (p = 0.001). Time to first postoperative defecation was shorter in CB (CB: d2 median versus CA: d3 median; p = 0.001). CB had a shorter length of hospital stay (p = 0.003), less requirement of intensive medical care (p = 0.001) and postoperative ventilation (p = 0.001). CB received higher doses of noradrenalin (p = 0.001). In the combined study cohort, there were more severe complications (G3-G5) in the case of a PFE ≥ 3000 ml (p = 0.034) and significantly more anastomotic leakage in the case of a PFE ≥ 4000 ml (p = 0.006).

CONCLUSIONS

Intraoperative fluid reduction in ovarian cancer surgery according to a PPVGFM is safe and significantly reduces ultrasevere postoperative complications. PFEs of ≥ 3000 ml and ≥ 4000 ml were identified as cutoffs for significantly more severe complications and anastomotic leakage, respectively.

Development of novel rectal/uterine clamping device

We developed a novel clamping device for laparoscopic surgery, free from conventional pinch structure, capable of uniformly occluding any ductal organ. This study aimed to evaluate performance of the new clamper compared to the pinch-type clamper. The new clamper consists of two metal bars with ties at each end, which enables parallel clamping. A resected porcine stomach was used, with an infusion tube at the anal end to increase intra-luminal pressure. The oral side of the stomach was clamped with either the new clamper or the pinch-type clamper, and their performances were evaluated in qualitative and semi-quantitative manner. Qualitative evaluation involved imaging the clamping site at intra-gastric pressures from 0 to 15 mmHg using microfocus computed tomography. The new clamper showed no gap even under increased intra-luminal pressure, while the pinch-type clamper showed a gap on the distal side. Quantitative evaluation measured bursting pressure under continuous air insufflation. Air leakages were observed in the new clamper at higher intra-luminal pressures than in the pinch-type clamper (46.1 mmHg vs. 13.6 mmHg, P < 0.01). Our new clamping device showed superior performance in preclinical setting compared to the conventional pinch-type clamper. We are currently working on its design freezing and aiming for early commercialization.

Prevention of hypotension after induction of general anesthesia using point-of-care ultrasound to guide fluid management: a randomized controlled trial

PURPOSE

Hypotension after induction of general anesthesia (GAIH) is common and is associated with postoperative complications including increased mortality. Collapsibility of the inferior vena cava (IVC) has good performance in predicting GAIH; however, there is limited evidence whether a preoperative fluid bolus in patients with a collapsible IVC can prevent this drop in blood pressure.

METHODS

We conducted a single-centre randomized controlled trial with adult patients scheduled to undergo elective noncardiac surgery under general anesthesia (GA). Patients underwent a preoperative point-of-care ultrasound scan (POCUS) to identify those with a collapsible IVC (IVC collapsibility index ≥ 43%). Individuals with a collapsible IVC were randomized to receive a preoperative 500 mL fluid bolus or routine care (control group). Surgical and anesthesia teams were blinded to the results of the scan and group allocation. Hypotension after induction of GA was defined as the use of vasopressors/inotropes or a decrease in mean arterial pressure < 65 mm Hg or > 25% from baseline within 20 min of induction of GA.

RESULTS

Forty patients (20 in each group) were included. The rate of hypotension after induction of GA was significantly reduced in those receiving preoperative fluids (9/20, 45% vs 17/20, 85%; relative risk, 0.53; 95% confidence interval, 0.32 to 0.89; P = 0.02). The mean (standard deviation) time to complete POCUS was 4 (2) min, and the duration of fluid bolus administration was 14 (5) min. Neither surgical delays nor adverse events occurred as a result of the study intervention.

CONCLUSION

A preoperative fluid bolus in patients with a collapsible IVC reduced the incidence of GAIH without associated adverse effects.

STUDY REGISTRATION

ClinicalTrials.gov (NCT05424510); first submitted 15 June 2022.

The 2023 Sir David Cuthbertson Lecture. A fluid journey: Experiments that influenced clinical practice

This review summarises some of my work on fluid and electrolyte balance over the past 25 years and shows how the studies have influenced clinical practice. Missing pieces in the jigsaw are filled in by summarising the work of others. The main theme is the biochemical, physiological and clinical problems caused by inappropriate use of saline solutions including the hyperchloraemic acidosis caused by 0.9% saline. The importance of accurate and near-zero fluid balance in clinical practice is also emphasised. Perioperative fluid and electrolyte therapy has important effects on clinical outcome in a U-shaped dose response fashion, in which excess or deficit progressively increases complications and worsens outcome. Salt and water overload, with weight gain in excess of 2.5 kg worsens surgical outcome, impairs gastrointestinal function and increases the risk of anastomotic dehiscence. Hyperchloraemic acidosis caused by overenthusiastic infusion of 0.9% saline leads to adverse outcomes and dysfunction of many organ systems, especially the kidney. Salt and water deficit causes similar adverse effects as fluid overload at the cellular level and also leads to worse outcomes. Serum albumin is shown to be affected mainly by dilution and inflammation and is not a good nutritional marker. These findings have been incorporated in the British consensus Guidelines on Intravenous Fluid Therapy for Adult Surgical Patients (GIFTASUP) and National Institute for Health and Care Excellence (NICE) guidelines on intravenous fluid therapy in adults in hospital and are helping change clinical practice and improve outcomes.

Fluid management strategies and their interaction with mechanical ventilation: from experimental studies to clinical practice

Patients on mechanical ventilation may receive intravenous fluids via restrictive or liberal fluid management. A clear and objective differentiation between restrictive and liberal fluid management strategies is lacking in the literature. The liberal approach has been described as involving fluid rates ranging from 1.2 to 12 times higher than the restrictive approach. A restrictive fluid management may lead to hypoperfusion and distal organ damage, and a liberal fluid strategy may result in endothelial shear stress and glycocalyx damage, cardiovascular complications, lung edema, and distal organ dysfunction. The association between fluid and mechanical ventilation strategies and how they interact toward ventilator-induced lung injury (VILI) could potentiate the damage. For instance, the combination of a liberal fluids and pressure-support ventilation, but not pressure control ventilation, may lead to further lung damage in experimental models of acute lung injury. Moreover, under liberal fluid management, the application of high positive end-expiratory pressure (PEEP) or an abrupt decrease in PEEP yielded higher endothelial cell damage in the lungs. Nevertheless, the translational aspects of these findings are scarce. The aim of this narrative review is to provide better understanding of the interaction between different fluid and ventilation strategies and how these interactions may affect lung and distal organs. The weaning phase of mechanical ventilation and the deresuscitation phase are not explored in this review.

POCUS and Fluid Responsiveness on Venoarterial ECMO

VA ECMO allows organ perfusion and oxygenation while awaiting myocardial recovery, cardiac transplantation, or long-term mechanical circulatory support. Diagnosis of hospital-acquired pneumonia (HAP) is a daily challenge for the clinician managing patients on venoarterial ECMO. Lung ultrasound (US) can be a valuable tool as the initial imaging modality for the diagnosis of pneumonia. Point-of-care US (POCUS) is broadly used in patients with ARDS. POCUS is recommended to be performed regularly in COVID-19 patients for respiratory failure management. In this review, we summarized the US characteristics of COVID-19 patients, mainly focusing on lung US and echocardiography. Point-of-care lung US (LUS) was demonstrated to be an effective tool in case of acute respiratory failure for ICU patients, community-acquired pneumonia, and ventilator-associated pneumonia. This review describes the usefulness of LUS in the early detection of HAP in cardiac critically ill patients under VA ECMO as well as assess its sonographic features.

Complications and Their Association with Mortality Following Emergency Gastrointestinal Surgery-an Observational Study

PURPOSE

Emergency gastrointestinal surgery is followed by a high risk of major complications and death. This study aimed to investigate which complications showed the strongest association with death following emergency surgery for gastrointestinal obstruction or perforation.

METHODS

We retrospectively included adults who had undergone emergency gastrointestinal surgery for radiologically verified obstruction or perforation at three Danish hospitals between 2014 and 2015. The exposure variables comprised 16 predefined Clavien-Dindo-graded complications. Cox regression with delayed entry was used to analyze the association of these complications with 90-day mortality. We adjusted for hospital, age, American Society of Anesthesiologists classification, pre-operative Sepsis-2 score, cardiac comorbidity, renal comorbidity, hypertension, active cancer, bowel obstruction or perforation, and the surgical procedure. Subgroup analyses were done for patients with gastrointestinal obstruction or perforation.

RESULTS

Of the 349 included patients, 281 (80.5%) experienced at least one complication. The risk of death was 20.6% (14) for patients with no complications and varied between 21 and 57% for patients with complications. Renal impairment (hazard ratio (HR): 6.8 (95%CI: 3.7-12.4)), arterial thromboembolic events (HR 4.8 (2.3-9.9)), and atrial fibrillation (HR 4.4 (2.8-6.8)) showed the strongest association with 90-day mortality. Atrial fibrillation was the only complication significantly associated with death in patients with gastrointestinal obstruction as well as perforation.

CONCLUSION

This study of patients undergoing emergency gastrointestinal surgery revealed that renal impairment, arterial thromboembolic events, and atrial fibrillation had the strongest association with death. Atrial fibrillation may serve as an in-situ marker of patients needing escalation of care.

Kinetics of 5% and 20% albumin: A controlled crossover trial in volunteers

BACKGROUND

Albumin for intravenous infusion is marketed in two concentrations, 20% and 5%, but how they compare with regard to plasma volume expansion over time is unclear.

METHODS

In a prospective crossover study, 12 volunteers received 3 ml kg-1 of 20% albumin and, on another occasion, 12 ml kg-1 of 5% albumin over 30 min. Hence, equivalent amounts of albumin were given. Blood was collected on 15 occasions over 6 h. Mass balance and volume kinetics were used to estimate the plasma volume expansion and the capillary leakage of albumin and fluid based on measurements of blood hemoglobin, plasma albumin, and the colloid osmotic pressure.

RESULTS

The greatest plasma volume expansion was 16.0 ± 6.4% (mean ± SD) with 20% albumin and 19.0 ± 5.2% with 5% albumin (p < .03). The volume expansion with 20% albumin corresponded to twice the infused volume. One third of the 5% albumin volume quickly leaked out of the plasma, probably because of the higher colloid osmotic pressure of the volunteer plasma (mean, 24.5 mmHg) than the albumin solution (19.1 mmHg). At 6 h, the capillary leakage amounted to 42 ± 15% and 47 ± 11% of the administered albumin with the 20% and 5% preparations, respectively (p = .28). The corresponding urine outputs were 547 (316-780) ml and 687 (626-1080) ml (median and interquartile range; p = .24).

CONCLUSION

The most important difference between the fluids was a dehydrating effect of 20% albumin when the same albumin mass was administered.

Postoperative fluid balance and outcomes after Pancreaticoduodenectomy: a retrospective study in 301 patients

BACKGROUND

The incidence of postoperative morbidity after pancreaticoduodenectomy (PD) is high; however, whether fluid management after surgery affects postoperative morbidity is unclear. This study aimed to determine whether fluid balance in patients undergoing PD is associated with postoperative complications and mortality.

METHODS

Data from a computer-based database of patients who underwent PD between 2016 and 2019 were retrospectively analyzed. Patients were stratified into four quartiles according to their fluid balance at 0-24, 24-48, 48-72, and 72-96 h after surgery. The predefined primary outcome measures were morbidity and mortality rates.

RESULTS

A total of 301 patients were included. The morbidity and mortality rates in the cohort were 56.5% and 3.7%, respectively. The most common complications after PD were postoperative pancreatic fistula (31.9%) and delayed gastric emptying (31.6%). Patients with a higher fluid balance in the 0-24-, 24-48-, and 48-72-h postoperative periods had a higher morbidity rate and longer hospital stay than those with a lower fluid balance (all P < 0.05). Patients with a fluid balance of 4212 mL during the postoperative 0-72 h were most likely to develop complications (P < 0.001). The area under the receiver operating characteristic curve was 0.71 (0.65-0.77), with a sensitivity of 58.24% and a specificity of 77.10%.

CONCLUSIONS

Higher postoperative fluid balance seems to be associated with increased morbidity after PD compared to lower fluid balance. Surgeons should pay close attention to the occurrence of complications in patients with a high fluid balance.

Comparison of liberal and goal-directed fluid therapy after small intestinal surgery for strangulating lesions in horses

BACKGROUND

There are few guidelines for the appropriate mode of fluid administration during and after colic surgery, and is challenging to reach the right balance while avoiding overhydration. This study aimed to compare goal-directed fluid therapy (GDFT) and 'liberal' fluid regimens (LFRs) in horses undergoing small intestinal surgery.

METHODS

Eighteen horses subjected to small intestinal surgery were matched according to the surgical lesion, type of anastomosis, length of resection, and duration of clinical signs. Horses in the LFR group were administered intravenous (IV) fluids for at least 24 h. In the GDFT group, IV fluids were administered only when considered necessary based on clinical parameters. Postoperative reflux (POR), packed cell volume, total protein, heart rate, venous lactate level, complications, and long-term survival rates were compared.

RESULTS

Three horses in the LFR and one in the GDFT group developed POR. Horses in the GDFT group had a shorter time interval to first oral water intake and shorter hospitalisation time. Postoperative complication rates and survival were not different between groups.

CONCLUSION

Further studies are necessary to set guidelines for the evaluation of hydration status and to plan postoperative fluid administration; however, GDFT may be a valid alternative to liberal fluid therapy after colic surgery.

Goal-directed fluid therapy in emergency abdominal surgery: a randomised multicentre trial

BACKGROUND

More than 50% of patients have a major complication after emergency gastrointestinal surgery. Intravenous (i.v.) fluid therapy is a life-saving part of treatment, but evidence to guide what i.v. fluid strategy results in the best outcome is lacking. We hypothesised that goal-directed fluid therapy during surgery (GDT group) reduces the risk of major complications or death in patients undergoing major emergency gastrointestinal surgery compared with standard i.v. fluid therapy (STD group).

METHODS

In a randomised, assessor-blinded, two-arm, multicentre trial, we included 312 adult patients with gastrointestinal obstruction or perforation. Patients in the GDT group received i.v. fluid to near-maximal stroke volume. Patients in the STD group received i.v. fluid following best clinical practice. Postoperative target was 0-2 L fluid balance. The primary outcome was a composite of major complications or death within 90 days. Secondary outcomes were time in intensive care, time on ventilator, time in dialysis, hospital stay, and minor complications.

RESULTS

In a modified intention-to-treat analysis, we found no difference in the primary outcome between groups: 45 (30%) (GDT group) vs 39 (25%) (STD group) (odds ratio=1.24; 95% confidence interval, 0.75-2.05; P=0.40). Hospital stay was longer in the GDT group: median (inter-quartile range), 7 (4-12) vs 6 days (4-8.5) (P=0.04); no other differences were found.

CONCLUSION

Compared with pressure-guided i.v. fluid therapy (STD group), flow-guided fluid therapy to near-maximal stroke volume (GDT group) did not improve the outcome after surgery for bowel obstruction or gastrointestinal perforation but may have prolonged hospital stay.

CLINICAL TRIAL REGISTRATION

EudraCT number 2015-000563-14; the Danish Scientific Ethics Committee and the Danish Data Protection Agency (REG-18-2015).

Prophylactic Norepinephrine Infusion Reduces Postoperative Complications and Hospitalization Time in Elderly Patients Undergoing Posterior Lumbar Spinal Fusion

This single-center prospective randomized controlled trial explores the effect of prophylactic norepinephrine infusion on the incidence of complications and hospitalization time in elderly patients (60-85 years old) undergoing posterior lumbar spinal fusion. In total, 129 elderly patients were randomized into two groups: a group that received norepinephrine during general anesthesia and a control group not receiving norepinephrine. The primary outcomes were in-hospital complications and 90-day postoperative complications and hospitalization time. The results show that in-hospital complications occurred in 24 of 60 patients (40%) in the control group versus 11 of 60 patients (18.3%) in the norepinephrine group (RR, 2.182; 95% CI, 1.177–4.045; P = 0.015). Cardiac events occurred significantly more frequently in the control than in the norepinephrine group. Total number of patients experiencing complications within 90 days postoperatively was lower in the norepinephrine (11 of 60; 18.3%) than in the control group (26 of 60; 43.3%; RR, 2.364; 95% CI, 1.288–4.339; P = 0.005). The median length of hospital stay was 17 days (11–27) in the control group and 15 days (10– 23) in the norepinephrine group (P = 0.01). The secondary outcomes were serum levels of syndecan-1, hyaluronic acid, heparan sulfate, and brain natriuretic peptide. Logistic regression analysis is used to describe the relationship between selected independent variables and in-hospital complications. Intraoperative total fluid, crystalloid, and colloid volumes were significantly higher in the control than in the norepinephrine group. The patients in the norepinephrine group had a higher MAP but a lower heart rate than those in the control group after the induction of anesthesia and intraoperatively. Syndecan-1, hyaluronic acid, and heparan sulfate serum levels showed a different course in the two groups. In conclusion, prophylactic norepinephrine infusion during posterior lumbar spinal fusion is preferable for elderly patients undergoing lumbar spinal fusion under general anesthesia. It can reduce postoperative complications and hospitalization time by reducing the injury to the vascular endothelium. This trial is registered with Clinical Trial Registration http://www.chictr.org.cn/showproj.aspx?proj=33660, identifier ChiCTR-1900021309.

Effect of intraoperative fluid volume on postoperative ileus after robot-assisted radical cystectomy

This study aimed to investigate the effect of intraoperative fluid volume on the postoperative ileus (POI) recovery period. A retrospective review of the Korean robot-assisted radical cystectomy database identified 718 patients who underwent robot-assisted radical cystectomy (RARC). Regression analyses were performed to identify the associations between the amount of intraoperative fluid administration (crystalloid/colloid/total), POI period (time to flatus/bowel movements), and length of hospital stay (LOS) after adjusting for covariates. In addition, we analyzed the risk factors for gastrointestinal complications and prolonged POI using a logistic regression model. An increasing volume of the administered crystalloid/total fluid was associated with prolonged POI (crystalloid R² = 0.0725 and P < 0.0001; total amount R² = 0.0812 and P < 0.0001), and the total fluid volume was positively associated with the LOS (R² = 0.099 and P < 0.0001). The crystalloid amount was a risk factor for prolonged POI (P < 0.001; odds ratio, 1.361; 95% confidence interval, 1.133–1.641; P < 0.001). In the context of RARC, increased intravenous fluids are associated with prolonged POI and longer LOS.

Analysis of Cumulative Fluid Balance Impact on the Stability of Gastrointestinal Tract Anastomosis

Anastomotic leakage is a serious postoperative complication following a low anterior resection of rectum. Current research in colorectal surgery focuses on searching for techniques which could minimize the risk of leakage. The main objective of this study was to evaluate the impact of cumulative fluid balance on microcirculatory changes at the anastomotic site.This experimental study used 15 domestic pigs; all of the animals underwent rectal resection. Then the animals were divided into three groups and received IV crystalloids at various rates, i.e. 5 ml/kg/h; 10 ml/kg/h; and 20 ml/kg/h. Large bowel micro-perfusion was measured using laser Doppler flowmetry during and following the surgical procedure.The experiments were successfully performed in all 15 cases. No animal died during the procedure or during the follow-up. We found no differences in micro-perfusion of the bowel between the experimental groups during the surgical procedure and during the follow-up period after the surgery. A significant decrease in micro-perfusion was observed after the transection of the inferior mesenteric artery in all the groups; again, no differences between the groups were observed.We did not confirm the original hypothesis that excessive load of IV crystalloids during the surgery would have a negative effect on bowel micro-perfusion and thus a negative effect on the healing of the anastomosis. However, laser Doppler flowmetry was found to have high accuracy in measuring tissue microcirculation and has the potential to be used in clinical practice.

Enhanced recovery pathways and patient-reported outcome measures in gynaecological oncology

Comprehensive peri-operative care for women with gynaecological malignancy is essential to ensure optimal clinical outcomes and maximise patient experience through the continuum of care. Implementation of peri-operative enhanced recovery pathways in gynaecological oncology have been repeatedly shown to improve postoperative recovery, decrease complications and reduce healthcare costs. With increasing emphasis being placed on patient-centred care in the current healthcare environment, incorporation of patient-reported outcome data collection and analysis within the enhanced recovery pathway as part of quality measurement is not only useful, but necessary. Inclusion of patient-reported outcome enhanced recovery pathway evaluation enables clinicians to capture authentic patient-reported parameters such as subtle symptoms, changes in function and multiple dimensions of well-being, directly from the source. These data guide the treatment course by encouraging shared decision-making between the patient and clinicians and provide the necessary foundation for ongoing peri-operative quality improvement efforts. Elements of the gynaecological oncology enhanced recovery pathway are divided into five phases of care: pre-admission; pre-operative; intra-operative; postoperative; and post-discharge. The development process starts with detailing each step of the patient's journey in all five phases, then identifying stakeholder groups responsible for care at each of these phases and assembling a multidisciplinary team including: gynaecologists; anaesthetists; nurses; nutritionists; physical therapists; and others, to provide input into the institutional pathway. To practically integrate patient-reported outcomes into an enhanced recovery pathway, a validated measurement tool should be incorporated into the peri-operative workflow. The ideal tool should be concise to facilitate longitudinal assessments by the clinical staff.

[Perioperative fluid management in major abdominal surgery]

Intravascular fluid administration belongs to the cornerstones of perioperative treatment with a substantial impact on surgical outcome especially with respect to major abdominal surgery. By avoidance of hypovolemia and hypervolemia, adequate perioperative fluid management significantly contributes to the reduction of insufficient tissue perfusion as a determinant of postoperative morbidity and mortality. The effective use of intravascular fluids requires detailed knowledge of the substances as well as measures to guide fluid therapy. Fluid management already starts preoperatively and should be continued in the postoperative setting (recovery room, peripheral ward) considering a patient-adjusted and surgery-adjusted hemodynamic monitoring. Communication between all team members participating in perioperative care is essential to optimize fluid management.

Contrast-enhanced paravertebrogram to confirm paravertebral catheter position in elective thoracic surgery: a proof of concept study

Background

Paravertebral pain catheters have been shown to be equally effective as epidural pain catheters for postoperative analgesia after thoracic surgery with the possible additional benefit of less hemodynamic effect. However, a methodology for verifying correct paravertebral catheter placement has not been tested or objectively confirmed in previous studies. The aim of the current study was to describe a technique to confirm the correct position of a paravertebral pain catheter using a contrast-enhanced paravertebrogram.

Methods

A retrospective cohort proof of concept study was performed including 10 consecutive patients undergoing elective thoracic surgery with radiographic contrast-enhanced confirmation of intraoperative paravertebral catheter placement (paravertebrogram).

Results

The results of the paravertebrograms, which were done in the operating room at the end of the procedure, verified correct paravertebral catheter placement in 10 of 10 patients. The radiographs documented dissemination of local anesthetic within the paravertebral space.

Conclusion

This proof of concept study demonstrated that a contrast-enhanced paravertebrogram could be used in conjunction with standard postoperative chest radiography to add valuable information for the assessment of paravertebral catheter placement. This technique has the potential to increase the accuracy and efficiency of postoperative analgesia, and to set a quality standard for future studies of paravertebral pain catheters.

Intraoperative Intravascular Effect of Lactated Ringer's Solution and Hyperoncotic Albumin During Hemorrhage in Cystectomy Patients

BACKGROUND

The intraoperative effect of 20% albumin on plasma volume during surgery involving major blood loss has not been explored extensively due to methodological difficulties. Crystalloids poorly expand the plasma volume, and using a colloid might then be a way to avoid fluid overload. As doubts have been raised about synthetic colloids, albumin solutions are currently used more extensively. This study presents a methodological development showing how plasma volume expansion can be studied in surgical settings with the coinfusion of 20% albumin and lactated Ringer's solution.

METHODS

In this single-arm, single-center feasibility study, an intravenous (i.v.) infusion of 3 mL·kg·BW-1 of 20% albumin was administered over 30 minutes to 23 cystectomy patients during the bleeding phase in addition to lactated Ringer's solution to correct blood loss. Blood samples were measured at regular intervals over a period of 300 minutes to estimate the blood volume expansion resulting from simultaneous infusions of lactated Ringer's and 20% albumin solutions, using a regression equation and the area under the volume-time curve method.

RESULTS

Mean hemorrhage was 974 mL (standard deviation [SD] ± 381). The regression method showed strong correlation (r2 = 0.58) between blood loss minus blood volume expansion and the independent effects of the infused volume of lactated Ringer's and 20% albumin solutions. The mean plasma volume expansion attributable to the infusion of lactated Ringer's solution amounted to 0.38 (95% confidence interval [CI], 0.31-0.49) of the infused volume; for the 20% albumin, it was 1.94 mL/mL (95% CI, 1.41-2.46 mL/mL) over 5 hours on average (regression method). The mean within-patient change was 0.20 mL/mL (± 0.06 mL/mL) for the lactated Ringer's solution and 2.20 mL/mL (±1.31 mL/mL) for the 20% albumin using the area under the volume-time curve method.

CONCLUSIONS

Blood volume expansion averaged 1.9-2.2 times the infused volume of 20% albumin during surgery associated with hemorrhage of around 1000 mL. This effect was long standing and approximately 5 times stronger than for the lactated Ringer's solution. Twenty percent albumin boosts the plasma volume expansion of lactated Ringer's solution to as high as 40% of the infused volume on the average, which is an effect that lasts at least 5 hours.

Hydroxyethyl starch for perioperative goal-directed fluid therapy in 2020: a narrative review

BACKGROUND

Perioperative fluid management - including the type, dose, and timing of administration -directly affects patient outcome after major surgery. The objective of fluid administration is to optimize intravascular fluid status to maintain adequate tissue perfusion. There is continuing controversy around the perioperative use of crystalloid versus colloid fluids. Unfortunately, the importance of fluid volume, which significantly influences the benefit-to-risk ratio of each chosen solution, has often been overlooked in this debate.

MAIN TEXT

The volume of fluid administered during the perioperative period can influence the incidence and severity of postoperative complications. Regrettably, there is still huge variability in fluid administration practices, both intra-and inter-individual, among clinicians. Goal-directed fluid therapy (GDFT), aimed at optimizing flow-related variables, has been demonstrated to have some clinical benefit and has been recommended by multiple professional societies. However, this approach has failed to achieve widespread adoption. A closed-loop fluid administration system designed to assist anesthesia providers in consistently applying GDFT strategies has recently been developed and tested. Such an approach may change the crystalloid versus colloid debate. Because colloid solutions have a more profound effect on intravascular volume and longer plasma persistence, their use in this more "controlled" context could be associated with a lower fluid balance, and potentially improved patient outcome. Additionally, most studies that have assessed the impact of a GDFT strategy on the outcome of high-risk surgical patients have used hydroxyethyl starch (HES) solutions in their protocols. Some of these studies have demonstrated beneficial effects, while none of them has reported severe complications.

CONCLUSIONS

The type and volume of fluid used for perioperative management need to be individualized according to the patient's hemodynamic status and clinical condition. The amount of fluid given should be guided by well-defined physiologic targets. Compliance with a predefined hemodynamic protocol may be optimized by using a computerized system. The type of fluid should also be individualized, as should any drug therapy, with careful consideration of timing and dose. It is our perspective that HES solutions remain a valid option for fluid therapy in the perioperative context because of their effects on blood volume and their reasonable benefit/risk profile.

Impact of postoperative weight gain on complications after liver surgery

BACKGROUND

Recent data has suggested that excessive perioperative weight gain may be associated with adverse outcomes after abdominal surgery, but this observation remains unexplored following liver surgery. The present study aimed to investigate the predictive value of perioperative weight fluctuation in predicting complications after liver surgery.

METHODS

Retrospective monocentric analysis of consecutive patients undergoing liver surgery between 2010 and 2016. Patients without available perioperative weight were excluded. Test variable was postoperative weight change (ΔWeight) measured on day 2 (POD2). Primary outcome was postoperative major morbidity according to Clavien classification (grades III-IV). Secondary outcomes were overall complications, Comprehensive Complication Index (CCI) and length of hospital stay (LoS). Area under the receiver operating characteristic curve (AUROC) and logistic regression with multivariable analysis were performed.

RESULTS

A total of 181 patients met the inclusion criteria. Major and overall postoperative complications were reported in 25 (14%) and 87 (48%) patients, respectively. On POD2, median ΔWeight was 2.6 Kg (IQR: 1.1-4.0). Patients with major complications showed increased ΔWeight of 4.2 Kg (IQR: 2.7-5.7), compared to 2.3 Kg (IQR: 0.9-3.7) in patients without major complications (p < 0.001). AUROC of ΔWeight for major complications was 0.74, determining an optimal cut-off of 3.5 Kg, which yielded a negative predictive value of 94%. Multivariable analysis identified ΔWeight ≥3.5 Kg as independent predictor of major complications (OR, 4.73; 95% CI, 1.51-14.80; p = 0.008).

CONCLUSION

ΔWeight ≥3.5 Kg was independently associated with major complications after liver surgery. Perioperative fluctuation of weight appears as an important predictor of adverse outcomes after liver surgery.

Fluid Therapy in Patients Undergoing Abdominal Surgery: A Bumpy Road Towards Individualized Management

Prudent intraoperative fluid replacement therapy, inotropes, and vasoactive drugs should be guided by adequate hemodynamic monitoring. The study aimed to evaluate the single-centre practice on intraoperative fluid therapy in abdominal surgery (AS). The evaluation, based on a review of medical files, included 235 patients (103 men), aged 60 ± 15 years who underwent AS between September and November 2017. Fluid therapy was analyzed in terms of quality and quantity. There were 124 high-risk patients according to the American Society of Anaesthesiologists Classification (ASA Class 3+) and 89 high-risk procedures performed. The median duration of procedures was 175 (IQR 106-284) min. Eleven patients died post-operatively. The median fluids volume was 10.4 mL/kg/h of anaesthesia, including 9.1 mL/kg/h of crystalloids and 2.7 mL/kg/h of synthetic colloids. Patients undergoing longer than the median procedures received significantly fewer fluids than those who underwent shorter procedures. The volume of fluids in the longer procedures depended on the procedural risk classification and was significantly greater in high-risk patients undergoing high-risk surgery. Patients who died received significantly more fluids than survivors. In all patients, a non-invasive blood pressure monitoring was used and only six patients had therapy guided by metabolic equilibrium. The fluid therapy used was liberal but complied with the recommendations regarding the type of fluid and risk-adjusted dosing. Hemodynamic monitoring was suboptimal and requires modifications. In conclusion, the optimization of intraoperative fluid therapy requires a balanced and standardized approach consistent with treatment procedures.

Minimally Invasive and Robotic Esophagectomy: A Review

Great advances have been made in the surgical management of esophageal disease since the first description of esophageal resection in 1913. We are in the era of minimally invasive esophagectomy. The current three main approaches to an esophagectomy are the Ivor Lewis technique, McKeown technique, and the transhiatal approach to esophagectomy. These operations were associated with a high morbidity and mortality. The recent advances in minimally invasive surgical techniques have greatly improved the outcomes of these surgical procedures. This article reviews the literature and describes the various techniques available for performing minimally invasive esophagectomy and robot-assisted esophagectomies, the history behind the development of these techniques, the variations, and the contemporary outcomes after such procedures.

Application of standardized hemodynamic protocols within enhanced recovery after surgery programs to improve outcomes associated with anastomotic leak and conduit necrosis in patients undergoing esophagectomy

Esophagectomy for cancer is associated with high risk for postoperative morbidity. The most serious regularly encountered complication is anastomotic leak and the most feared individual complication is conduit necrosis. Both of these complications affect the length of stay, mortality, quality of life, and survival for patients undergoing esophageal resection. The maintenance of conduit viability is of primary importance in the perioperative care of patients following esophageal resection. It has been shown that restrictive fluid management may be associated with improved postoperative outcomes in abdominal and other types of surgery, but many factors can affect the incidence of anastomotic leak and the viability of the gastric conduit. We have performed a comprehensive review with the aim to give an overview of the available evidence for the use of standardized hemodynamic protocols (SHPs) for esophagectomy and review the hemodynamic protocol, which has been applied within a standardized clinical pathway (SCP) at the Department of Thoracic surgery at the Virginia Mason Medical Center between 2004-2018 where the anastomotic leak rate over the period has been 5.2% and the incidence of conduit necrosis requiring surgical management is zero. The literature review demonstrates that there are few high quality studies that provide scientific evidence for the use of a SHP. The evidence indicates that the use of goal-directed hemodynamic monitoring might be associated with a reduced risk for postoperative complications, shortened length of stay, and decreased need for intensive care unit stay. We propose that the routine application of a SHP can provide a uniform infrastructure to optimize conduit perfusion and decrease the incidence of anastomotic leak.

Goal-directed fluid therapy on laparoscopic colorectal surgery within enhanced recovery after surgery program

INTRODUCTION

Enhanced recovery after surgery protocols (ERAS) are used in peri-operative care to reduce the stress response to surgical aggression. As fluid overload has been associated with increased morbidity and delayed hospital discharge, a major aspect of this is fluid management. Intra-operative goal-directed fluid protocols have been shown to reduce post-operative complications, particularly in high risk patients.?.

OBJECTIVE

To compare 2fluid therapy models (zero-balance versus goal-directed fluid therapy) in patients who were scheduled for laparoscopic colorectal surgery within an ERAS program, recording the rate of complications such as surgical site infection, ileus, post-operative náusea and vomiting, and variability of the estimated glomerular filtration rate (eGFR).

MATERIALS AND METHODS

An observational, retrospective study was conducted including adults who were scheduled for elective laparoscopic colorectal surgery within an ERAS program, and to investigate the postoperative complication rate.

RESULTS

A total of 128 patients were included in this study; 43 (33.6%) in the zero-balance group and 85 (66.4%) in the goal-directed fluid therapy group. The total fluids administered was lower in the goal-directed fluid therapy group, as well as the incidence of post-operative complications (surgical site infection, anastomotic leak, ileus, and postoperative náusea and vomiting). No significant differences were found for length of stay, intra-operative urine output, and variability of the eGFR.?.

CONCLUSION

The results of this study show that by using a goal-directed fluid therapy algorithm, the total amount of fluids administered can be reduced, as well as obtaining a lower incidence of post-operative complications.

Stringent fluid management might help to prevent postoperative ileus after loop ileostomy closure

PURPOSE

The present study aimed to analyze the impact of perioperative fluid management on postoperative ileus (POI) after loop ileostomy closure.

METHODS

Consecutive loop ileostomy closures over a 6-year period (May 2011-May 2017) were included. Main outcomes were POI, defined as time to first stool beyond POD 3, and postoperative complications of any grade. Critical fluid management-related thresholds including postoperative weight gain were identified through receiver operator characteristics (ROC) analysis and tested in a multivariable analysis.

RESULTS

Of 238 included patients, 33 (14%) presented with POI; overall complications occurred in 91 patients (38%). 1.7 L IV fluids at postoperative day (POD) 0 was determined a critical threshold for POI (area under ROC curve (AUROC), 0.64), yielding a negative predictive value (NPV) of 93%. Further, a critical cutoff for a postoperative weight gain of 1.2 kg at POD 2 was identified (AUROC, 0.65; NPV, 95%). Multivariable analysis confirmed POD 0 fluids of > 1.7 L (OR, 4.7; 95% CI, 1.4-15.3; p = 0.01) and POD 2 weight gain of > 1.2 kg (OR, 3.1; 95% CI, 1-9.4; p = 0.046) as independent predictors for POI.

CONCLUSIONS

Perioperative fluid administration of > 1.7 L and POD 2 weight gain of > 1.2 kg represent critical thresholds for POI after loop ileostomy closure.

Systematic Review and Meta-analysis of Restrictive Perioperative Fluid Management in Pancreaticoduodenectomy

BACKGROUND

There is significant interest and controversy surrounding the effect of restrictive fluid management on outcomes in major gastrointestinal surgery. This has been most studied in colorectal surgery, although the literature relating to pancreaticoduodenectomy (PD) patients is growing. The aim of this paper was to generate a comprehensive review of the available evidence for restrictive perioperative fluid management strategies and outcomes in PD.

METHODS

MEDLINE/PubMed, Embase, and the Cochrane Library were searched from inception to April 2017. A review protocol was utilized and registered with PROSPERO. Primary citations that evaluated perioperative fluid management in PD, including those as part of a clinical pathway, were considered. The primary outcome was postoperative pancreatic fistula (POPF). Secondary outcomes included delayed gastric emptying (DGE), complication rate, length of stay (LOS), mortality, and readmission.

RESULTS

A total of six studies involving 846 patients were included (2009-2015), of which four were RCTs. Pooled analysis of RCTs and high-quality observational studies found no effect of restrictive intraoperative fluid management on POPF, DGE, complication rate, LOS, mortality, and readmission. Only one study assessed postoperative fluid management exclusively and found prolonged LOS in patients in the restricted fluid group.

CONCLUSION

Based on results of RCTs and high-quality observational studies, intraoperative fluid restriction in PD has not been shown to significantly affect postoperative outcomes. There are too few studies assessing postoperative fluid management to draw conclusions at this time.

Goal-directed fluid therapy does not reduce postoperative ileus in gastrointestinal surgery: A meta-analysis of randomized controlled trials

BACKGROUND

Perioperative goal-directed fluid therapy (GDFT) aiming to maintain individual fluid balance based on sensitive parameters was prevalent in major surgery, especially in enhanced recovery after surgery (ERAS) pathway. This meta-analysis was conducted for the purpose of evaluating whether GDFT impacts on occurrence of postoperative ileus and whether its application is worthwhile in gastrointestinal surgery.

METHODS

A systematic search of RCTs compared GDFT with other fluid management in patients undergoing gastrointestinal surgery from the PubMed, Web of Science, Embase, Cochrane Library databases was implemented. The primary outcome is incidence of postoperative ileus. Other outcome measures were length of hospital stay (LOS), postoperative morbidity and mortality. Subgroup analysis was planed a prior to verify the definite role of GDFT.

RESULTS

12 trials consisted of 1836 patients were included in the final analysis. GDFT did not influence the occurrence of postoperative ileus (relative risk, RR 0.71, 95% confidence interval, CI 0.47-1.07, P = .10), with moderate heterogeneity (I = 29%, P = .16). No difference was found between GDFT and control groups in LOS (mean difference -0.17 days, 95% CI -0.73 to 0.39, P = .55), total complication rate (RR 0.92, 95% CI 0.81-1.05, P = .23), and 30-day mortality (RR 0.91, 95% CI 0.47-1.75, P = .77). In other secondary outcomes, only wound infection rate was lower in the GDFT group (RR 0.68, 95% CI 0.50-0.93, P = .02). When performed subgroup analysis, GDFT was superior in reduction ileus only when compared with standard therapy or in those outside ERAS.

CONCLUSIONS

It is possible that GDFT dose not affect the occurrence of postoperative ileus in gastrointestinal surgery. It scarcely influences postoperative morbidity and mortality as well. However, lower incidence of ileus is observed in GDFT group either outside ERAS or compared with standard fluid therapy. Probably, GDFT may not be necessary in the ERAS pathway or if a hybrid approach is adopted.

Perioperative Net Fluid Balance Predicts Pancreatic Fistula After Pancreaticoduodenectomy

BACKGROUND

Our goal was to evaluate the relationship between perioperative fluid administration and the development of clinically relevant postoperative pancreatic fistula (CR-POPF) after pancreaticoduodenectomy (PD).

METHODS

Retrospectively, we analyzed fluid balance over the first 72 h in 104 consecutive patients who underwent PD between 2013 and 2017. Patients were categorized into tertiles (low, medium, and high) by net fluid balance.

RESULTS

POPF was identified in 17.3% of patients (n = 18). No significant demographic differences were identified among tertiles. Similarly, there were no differences in ASA, smoking status, hemoglobin A1C, pathologic findings, operative time, blood loss, intraoperative fluid administration, use of pancreatic stents, use of epidurals, or postoperative lactate. Patients with high 72-h net fluid balance had significantly increased rates of POPF compared with those in the medium and low tertiles (31.4% vs. 11.4% vs. 8.8%, p = 0.02). On multivariate analysis, increasing net fluid balance remained associated with CR-POPF (OR 1.26, CI 1.03-1.55, p = 0.03).

CONCLUSION

High net 72-h fluid balance is an independent predictor of POPF after PD. Given ongoing efforts to minimize PD morbidity, net fluid balance may represent a clinical predictor and, possibly, a modifiable target for prevention of POPF.

Postoperative hemodynamic instability and monitoring

PURPOSE OF REVIEW

The purpose of the review is to identify the recently validated minimally invasive or noninvasive monitoring devices used to both monitor and guide resuscitation in the critically ill patients.

RECENT FINDINGS

Recent advances in noninvasive measures of blood pressure, blood flow, and vascular tone have been validated and complement existing minimally invasive and invasive monitoring techniques. These monitoring approaches should be used within the context of a focused physical examination and static vital sign analysis. When available, measurement of urinary output is often included. All studies show that minimally invasive and noninvasive measure of arterial pressure and cardiac output are possible and often remain as accurate as invasive measures. The noninvasive techniques degrade in severe circulatory failure and the use of vasopressor therapy. Importantly, these output parameters form the treatment goals for many goal-directed therapies protocols.

SUMMARY

When coupled with a focused physical examination and functional hemodynamic monitoring analyses, these measures become even more specific at defining volume responsiveness and vasomotor tone and can be used to drive resuscitation strategies.

Pringle maneuver increases the risk of anastomotic leakage after colonic resection in rats

BACKGROUND

Many centers use the Pringle's maneuver during liver resections. Since this maneuver might impair healing of bowel anastomoses, we evaluated its influence on the healing of colonic anastomosis in rats.

METHODS

Male Wistar rats underwent median laparotomy and sigmoid resection with end-to-end anastomosis under inhalation anesthesia. Thereafter, rats received a 25 minutes Pringle's maneuver (PM, group 1) or were kept under anesthesia for the same period of time (group 2). The anastomotic bursting pressure (BP) was measured on postoperative days (POD) 3, 6 and 9. Hematoxylin and Eosin (H&E) staining was used for histopathological evaluation of the anastomosis. The Mann-Whitney U and χ² -tests were used, p<0.05 values were considered significant.

RESULTS

All animals (n=48) lost body weight (BW) until POD3 (95.2% vs. 85.7%, p=0.003), and BW remained lower after PM (106.2% vs. 92.8%, p=0.001). The anastomotic BP was lower in group 1 compared to group 2 on POD 3 (116mmHg vs. 176.28mmHg, p=0.001), POD 6 (182.8mmHg vs. 213mmHg, p=0.029) and POD 9 (197.2mmHg vs. 251.7mmHg, p=0.009), and mortality was higher in group 1 (1 vs. 7, p=0.022).

CONCLUSIONS

Pringle's maneuver increases anastomotic complications in rats. Therefore, a Pringle's maneuver should be avoided during simultaneous liver and colorectal surgery.

The Effect of a Surgery-Specific Cardiac Output–Guided Haemodynamic Algorithm on Outcomes in Patients Undergoing Pancreaticoduodenectomy in a High-Volume Centre: A Retrospective Comparative Study

In this retrospective observational study performed in a high-volume hepatobiliary–pancreatic unit, we evaluated the effect of a surgery-specific goal-directed therapy (GDT) physiologic algorithm on complications and length of hospital stay. We compared patients who underwent pancreaticoduodenectomy with either a standardised Enhanced Recovery After Surgery program (usual care group), or a standardised Enhanced Recovery After Surgery program in combination with a surgery-specific cardiac output–guided algorithm (GDT group). We included 145 consecutive patients: 47 in the GDT group and 98 in the usual care group. Multivariable associations between GDT and lengths of stay and complications were investigated using negative binomial regression. Postoperative complications were common and occurred at similar frequencies amongst the GDT and usual care groups: 64% versus 68% respectively, P=0.71; odds ratio 0.82; (95% confidence interval 0.39–1.70). There were fewer cardiorespiratory complications in the GDT group. Median (interquartile range) length of hospital stay was ten days (8.0–14.0) in the GDT group compared to 13 days (8.8–21.3) in the usual care group, P=0.01. Median (interquartile range) total intraoperative fluid was 3,000 ml (2,050–4,175) in the GDT group compared to 4,500 ml (3,275–5,325) in the usual care group, P <0.0001; but by day one, the median (interquartile range) fluid balance was similar (1,198 ml [700–1,729] in the GDT group versus 977 ml [419–2,044] in the usual care group, P=0.96). Use of vasoactive medications was higher in the GDT group. In our patients undergoing pancreaticoduodenectomy, GDT was associated with restrictive intraoperative fluid intervention, fewer cardiorespiratory complications and a shorter hospital length of stay compared to usual care. However, we could not exclude an influence of surgical caseload, which we have previously found to be an important variable. We also could not relate the increased hospital length of stay to cardiorespiratory complications in individual patients. Therefore, these observational retrospective findings would require confirmation in a prospective randomised study.

Stroke volume variation (SVV) and pulse pressure variation (PPV) as indicators of fluid responsiveness in sevoflurane anesthetized mechanically ventilated euvolemic dogs

Changes in stroke volume variation (SVV) and pulse pressure variation (PPV) in response to fluid infusion were experimentally evaluated during vecuronium infusion and sevoflurane anesthesia in 5 adult, mechanically ventilated, euvolemic, beagle dogs. Sequential increases in central venous pressure (CVP; 3-7[baseline], 8-12, 13-17, 18-22 and 23-27 mmHg) were produced by infusing lactated Ringer's solution and 6% hydroxyethyl starch solution. Heart rate (beats/min), right atrial pressure (RAP, mmHg), pulmonary arterial pressure (PAP, mmHg), pulmonary capillary wedge pressure (PCWP, mmHg), transpulmonary thermodilution cardiac output (TPTDCO, l/min), stroke volume (SV, ml/beat), arterial blood pressure (ABP, mmHg), extravascular lung water (EVLW, ml), pulmonary vascular permeability index (PVPI, calculated), SVV (%), PPV (%) and systemic vascular resistance (SVR, dynes/sec/cm⁵) were determined at each predetermined CVP range. Heart rate (P=0.019), RAP (P<0.001), PAP (P<0.001), PCWP (P<0.001), TPTDCO (P=0.009) and SV (P=0.04) increased and SVR (P<0.001), SVV (P<0.001) and PPV (P<0.001) decreased associated with each stepwise increase in CVP. Arterial blood pressure, EVLW, PVPI and the arterial partial pressures of oxygen and carbon dioxide did not change. The changes in SVV and PPV directly reflected the fluid load and the minimum threshold values for detecting fluid responsiveness were SVV ≥11% and PPV ≥7% in dogs.

Low Versus Standard Urine Output Targets in Patients Undergoing Major Abdominal Surgery: A Randomized Noninferiority Trial

OBJECTIVE

To determine whether a low perioperative minimum urine output target is safe and fluid sparing when compared with the standard target.

BACKGROUND

A minimum hourly urine output of 0.5 mL/kg is a key target guiding perioperative fluid therapy. Few data support this standard practice, which may contribute to perioperative fluid overloading.

METHODS

We randomized patients without significant risk factors for acute kidney injury undergoing elective colectomy to a minimum urine output target of 0.2 mL/kg/h (low group) or 0.5 mL/kg/h (standard group) from induction of anesthesia until 8 AM 2 days after surgery. Maintenance fluids were standardized and additional fluids administered to achieve the targets. Primary outcome was noninferiority for urine neutrophil gelatinase-associated lipocalin on the day after surgery.

RESULTS

Between November 21, 2011 and July 11, 2013, 40 participants completed the study. The low group received 3170 mL (95% confidence interval 2380-3960) intravenous fluids versus 5490 mL (95% confidence interval 4570-6410) in the standard group (P = 0.0004), and was noninferior for neutrophil gelatinase-associated lipocalin [14.7 μg/L (interquartile range 7.60-28.9) vs 18.4 μg/L (interquartile range 8.30-21.2); Pnoninferiority = 0.0011], serum cystatin C (Pnoninferiority < 0.0001), serum creatinine (Pnoninferiority = 0.0004), and measured glomerular filtration (Pnoninferiority = 0.0003). Effective renal plasma flow increased in both groups after surgery, and more in the standard group (Pnoninferiority = 0.125).

CONCLUSIONS

A perioperative urine output target of 0.2 mL/kg/h is noninferior to the standard target of 0.5 mL/kg/h and results in a large intravenous fluid sparing. This target should be adopted in surgical patients without significant kidney injury risk factors.

Complications after pancreaticoduodenectomy are associated with higher amounts of intra- and postoperative fluid therapy: A single center retrospective cohort study

Background

Perioperative mortality after pancreaticoduodenectomy has decreased significantly in high-volume centers, but morbidity remains high. Restrictive perioperative fluid management may contribute to reduced complication rates after various surgical procedures. The aim of this study was to determine whether there is a correlation between the amount of fluid administered and postoperative complications. We hypothesized that higher amounts of intra- and total fluid is associated with greater postoperative morbidity.

Materials and methods

We retrospectively examined data of 553 patients who underwent pancreaticoduodenectomy at University of Freiburg Medical Center between 2001 and 2013. Data on intra - and postoperative fluid administration (until postoperative day 5) were obtained from anesthesiological and surgical records. Data on complications were retrieved from our institutional pancreatic database.

Results

The median values for intra- and total fluid administered were 6000 ml (range 400–15,000 ml) and 13,600 ml (range 5000–57,700 ml), respectively. The overall in-hospital mortality was 1.9% (no correlation with fluid administration). Patients who received more than 6000 ml intraoperative fluid had more wound infections (P = 0.049), intra-abdominal abscesses (P = 0.020) and postoperative interventions (P = 0.007). In patients who received more than 14000 ml fluid until postoperative day 5 all evaluated types of postoperative complications (infectious, fistula, delayed gastric emptying, bleeding) and re-interventions occurred significantly more frequently than in patients who received less than 14,000 ml (P < 0.05–0.001).

Conclusions

Higher amounts of fluids may contribute to postoperative complications. More studies are needed to adequately assess the use of intra/postop fluid therapy.

•

High amounts of perioperative fluid may impair surgical outcome of pancreatic resection.

•

>6000 ml intraoperative fluid was associated with more infectious complications.

•

>14 000 ml total fluid by postoperative day 5 was linked with many complications.

•

Complications included infections, fistulas, delayed gastric emptying and bleeding.

•

Prospective randomized controlled trials should investigate postoperative fluid therapy.

Liberal perioperative fluid administration is an independent risk factor for morbidity and is associated with longer hospital stay after rectal cancer surgery

INTRODUCTION Recent studies have advocated the use of perioperative fluid restriction in patients undergoing major abdominal surgery as part of an enhanced recovery protocol. Series reported to date include a heterogenous group of high- and low-risk procedures but few studies have focused on rectal cancer surgery alone. The aim of this study was to assess the effects of perioperative fluid volumes on outcomes in patients undergoing elective rectal cancer resection. METHODS A prospectively maintained database of patients with rectal cancer who underwent elective surgery over a 2-year period was reviewed. Total volume of fluid received intraoperatively was calculated, as well as blood products required in the perioperative period. The primary outcome was postoperative morbidity (Clavien-Dindo grade I-IV) and the secondary outcomes were length of stay and major morbidity (Clavien-Dindo grade III-IV). RESULTS Over a 2-year period (2012-2013), 120 patients underwent elective surgery with curative intent for rectal cancer. Median total intraoperative fluid volume received was 3680ml (range 1200-9670ml); 65/120 (54.1%) had any complications, with 20/120 (16.6%) classified as major (Clavien-Dindo grade III-IV). Intraoperative volume >3500ml was an independent risk factor for the development of postoperative all-cause morbidity (P=0.02) and was associated with major morbidity (P=0.09). Intraoperative fluid volumes also correlated with length of hospital stay (Pearson's correlation coefficient 0.33; P<0.01). CONCLUSIONS Intraoperative fluid infusion volumes in excess of 3500ml are associated with increased morbidity and length of stay in patients undergoing elective surgery for rectal cancer.

Postoperative fluid overload is a risk factor for adverse surgical outcome in patients undergoing esophagectomy for esophageal cancer: a retrospective study in 335 patients

Background

Restrictive intraoperative fluid management is increasingly recommended for patients undergoing esophagectomy. Controversy still exists about the impact of postoperative fluid management on perioperative outcome.

Methods

We retrospectively examined 335 patients who had undergone esophagectomy for esophageal cancer at the University Hospital Freiburg between 1996 and 2014 to investigate the relation between intra- and postoperative fluid management and postoperative morbidity after esophagectomy.

Results

Perioperative morbidity was 75%, the in-hospital mortality 8%. A fluid balance above average on the operation day was strongly associated with a higher rate of postoperative mortality (21% vs 3%, p < 0.001) and morbidity (83% vs 66%, p = 0.001). Univariate analysis for risk factors for adverse surgical outcome (Clavien ≥ III) identified ASA-score (p = 0.002), smoking (p = 0.036), reconstruction by colonic interposition (p = 0.036), cervical anastomosis (p = 0.017), blood transfusion (p = 0.038) and total fluid balance on the operation day and on POD 4 (p = 0.001) as risk factors.

Multivariate analysis confirmed only ASA-score (p = 0.001) and total fluid balance (p = 0.001) as independent predictors of adverse surgical outcome.

Conclusion

Intra- and postoperative fluid overload is strongly associated with increased postoperative morbidity. Our results suggest restrictive intra- and especially postoperative fluid management to optimize the outcome after esophagectomy.

Impact of a Potassium-enriched, Chloride-depleted 5% Glucose Solution on Gastrointestinal Function after Major Abdominopelvic Surgery

Background

Gastrointestinal (GI) complications often delay recovery after radical cystectomy with urinary diversion. The authors investigated if perioperative administration of a potassium-enriched, chloride-depleted 5% glucose solution (G5K) accelerates recovery of GI function.

Methods

This randomized, parallel-group, single-center double-blind trial included 44 consecutive patients undergoing radical cystectomy and pelvic lymph node dissection with urinary diversion. Patients were randomized to receive either a G5K (G5K group) solution or a Ringer’s maleate solution (control group). Fluid management aimed for a zero fluid balance. Primary endpoint was time to first defecation. Secondary endpoints were time to normal GI function, need for electrolyte substitution, and renal dysfunction.

Results

Time to first defecation was not significantly different between groups (G5K group, 93 h [19 to 168 h] and control group, 120 h [43 to 241 h]); estimator of the group difference, −16 (95% CI, −38 to 6); P = 0.173. Return of normal GI function occurred faster in the G5K group than in the control group (median, 138 h [range, 54 to 262 h] vs. 169 h [108 to 318 h]); estimator of the group difference, −38 (95% CI, −74 to −12); P = 0.004. Potassium and magnesium were less frequently substituted in the G5K group (13.6 vs. 54.5% [P = 0.010] and 18.2 vs. 77.3% [P &lt; 0.001]), respectively. The incidence of renal dysfunction (Risk, Injury, Failure, Loss and End-stage kidney disease stage “risk”) at discharge was 9.1% in the G5K group and 4.5% in the control group; P = 1.000.

Conclusions

Perioperative administration of a G5K did not enhance first defecation, but may accelerate recovery of normal GI function, and reduces potassium and magnesium substitution after radical cystectomy and urinary diversion.

Fluid therapy in the perioperative setting-a clinical review

BACKGROUND

Perioperative hypovolemia and fluid overload have effects on both complications following surgery and on patient survival. Therefore, the administration of intravenous fluids before, during, and after surgery at the right time and in the right amounts is of great importance. This review aims to analyze the literature concerning perioperative fluid therapy in abdominal surgery and to provide evidence-based recommendations for clinical practice.

RESULTS

Preoperative oral or intravenous administration of carbohydrate containing fluids has been shown to improve postoperative well-being and muscular strength and to reduce insulin resistance. Hence, the intake of fluid (preferably containing carbohydrates) should be encouraged up to 2 h prior to surgery in order to avoid dehydration. Excessive intravenous fluid administration adds to tissue inflammation and edema formation, thereby compromising tissue healing. During major abdominal surgery a "zero-balance" intraoperative fluid strategy aims at avoiding fluid overload (and comparable to the so-called restrictive approach) as well as goal-directed fluid therapy (GDT). Both proved to significantly reduce postoperative complications when compared to "standard fluid therapy". Trials comparing "restrictive" or zero-balance and GDT have shown equal results, as long as fluid overload is avoided in the GDT group as well (categorized as "zero-balance GDT"). It is possible that high-risk surgical patients, such as those undergoing acute surgery, may benefit from the continuous monitoring of circulatory status that the GDT provides. Data on this group of patients is not available at present, but trials are ongoing.

CONCLUSION

In elective surgery, the zero-balance approach has shown to reduce postoperative complications and is easily applied for most patients. It is less expensive and simpler than the zero-balance GDT approach and therefore recommended in this review. In outpatient surgery, 1-2 L of balanced crystalloids reduces postoperative nausea and vomiting and improves well-being.

Impact of late fluid balance on clinical outcomes in the critically ill surgical and trauma population

PURPOSE

Management of fluid status in critically ill patients poses a significant challenge due to limited literature. This study aimed to determine the impact of late fluid balance management after initial adequate fluid resuscitation on in-hospital mortality for critically ill surgical and trauma patients.

MATERIALS AND METHODS

This single-center retrospective cohort study included 197 patients who underwent surgical procedure within 24 hours of surgical intensive care unit admission. Patients with high fluid balance on postoperative day 7 (>5 L) were compared with those with a low fluid balance (≤5 L) with a primary end point of in-hospital mortality. Subgroup analyses were performed based on diuretic administration, diuretic response, and type of surgery.

RESULTS

High fluid balance was associated with significantly higher in-hospital mortality (30.2 vs 3%, P<.001) compared with low fluid balance; this relationship remained after multivariable regression analysis. High fluid balance was associated with increased mortality, independent of diuretic administration, diuretic response, and type of surgery.

CONCLUSIONS

Consistent with previous literature, high fluid balance on postoperative day 7 was associated with increased in-hospital mortality. Patients who received and responded to diuretic therapy did not demonstrate improved clinical outcomes, which questions their use in the postoperative period.

Operator-related risk factors of anastomotic leaks after colorectal surgery: an up-to-date

Digestive fistulas are a major complication after digestive surgery. Anastomotic leakage increases the hospitalization time, the prognosis and survival rate after colorectal surgical interventions.

The factors involved are either systemic (determined by the patients’ co-morbidities), or local (vicious surgical technique or the injuries produced by the disease that requires the anastomosis). Although there are many studies regarding the risk factors of anastomotic leaks, there is no consensus for the role played by each one of them in the healing process of digestive sutures. Most authors sustain that the importance of systemic factors is secondary, the main role being played by the surgeon and the local conditions of the anastomosis.

Knowledge of the risk factors can lead to new methods of reducing the incidence of anastomotic leaks by improving vascularization, limiting the tension and the duration of surgery, and by new surgical techniques used for digestive sutures.

Perioperative cardiovascular monitoring of high-risk patients: a consensus of 12

A significant number of surgical patients are at risk of intra- or post-operative complications or both, which are associated with increased lengths of stay, costs, and mortality. Reducing these risks is important for the individual patient but also for health-care planners and managers. Insufficient tissue perfusion and cellular oxygenation due to hypovolemia, heart dysfunction or both is one of the leading causes of perioperative complications. Adequate perioperative management guided by effective and timely hemodynamic monitoring can help reduce the risk of complications and thus potentially improve outcomes. In this review, we describe the various available hemodynamic monitoring systems and how they can best be used to guide cardiovascular and fluid management in the perioperative period in high-risk surgical patients.

Perioperative fluid therapy: a statement from the international Fluid Optimization Group

BACKGROUND

Perioperative fluid therapy remains a highly debated topic. Its purpose is to maintain or restore effective circulating blood volume during the immediate perioperative period. Maintaining effective circulating blood volume and pressure are key components of assuring adequate organ perfusion while avoiding the risks associated with either organ hypo- or hyperperfusion. Relative to perioperative fluid therapy, three inescapable conclusions exist: overhydration is bad, underhydration is bad, and what we assume about the fluid status of our patients may be incorrect. There is wide variability of practice, both between individuals and institutions. The aims of this paper are to clearly define the risks and benefits of fluid choices within the perioperative space, to describe current evidence-based methodologies for their administration, and ultimately to reduce the variability with which perioperative fluids are administered.

METHODS

Based on the abovementioned acknowledgements, a group of 72 researchers, well known within the field of fluid resuscitation, were invited, via email, to attend a meeting that was held in Chicago in 2011 to discuss perioperative fluid therapy. From the 72 invitees, 14 researchers representing 7 countries attended, and thus, the international Fluid Optimization Group (FOG) came into existence. These researches, working collaboratively, have reviewed the data from 162 different fluid resuscitation papers including both operative and intensive care unit populations. This manuscript is the result of 3 years of evidence-based, discussions, analysis, and synthesis of the currently known risks and benefits of individual fluids and the best methods for administering them.

RESULTS

The results of this review paper provide an overview of the components of an effective perioperative fluid administration plan and address both the physiologic principles and outcomes of fluid administration.

CONCLUSIONS

We recommend that both perioperative fluid choice and therapy be individualized. Patients should receive fluid therapy guided by predefined physiologic targets. Specifically, fluids should be administered when patients require augmentation of their perfusion and are also volume responsive. This paper provides a general approach to fluid therapy and practical recommendations.