A systematic review and meta-analysis on the use of preemptive hemodynamic intervention to improve postoperative outcomes in moderate and high-risk surgical patients

Perioperative Management of Elderly Patients with Gastrointestinal Malignancies: The Contribution of Anesthesia

INTRODUCTION

Elderly patients suffering from gastrointestinal malignancies are particularly prone to perioperative complications. Elderly patients often present with reduced physiological reserves, and comorbidities can limit treatment options and promote complications. Surgeons and anesthesiologists must be aware of strategies required to deal with this vulnerable subgroup.

METHODS

We provide a brief review of current and emerging perioperative strategies for the treatment of elderly patients with gastrointestinal malignancies and frequent comorbidities.

RESULTS

Especially in combination with advanced age, the effects of malignancies can be devastating, bringing new health challenges, exacerbating preexisting conditions, and exerting severe psychological strain. An interdisciplinary assessment and process planning provide an ideal setting to identify and prevent potential complications, especially in regards to frailty and cardiovascular risk. In addition, important perioperative considerations are presented, such as malnutrition, fasting, intraoperative neuromonitoring, and hemodynamic control, as well as postoperative early mobilization, pain, and delirium management.

CONCLUSION

The decisions and interventions made in the perioperative stage can positively influence many intra- and postoperative factors, significantly improving the chances of successful treatment of elderly cancer patients. Appropriate management can help prevent or mitigate complications, secure a quick recovery, and improve short- and long-term outcomes.

Goal-directed Fluid Therapy Does Not Reduce Primary Postoperative Ileus after Elective Laparoscopic Colorectal Surgery: A Randomized Controlled Trial

BACKGROUND

Inadequate perioperative fluid therapy impairs gastrointestinal function. Studies primarily evaluating the impact of goal-directed fluid therapy on primary postoperative ileus are missing. The objective of this study was to determine whether goal-directed fluid therapy reduces the incidence of primary postoperative ileus after laparoscopic colorectal surgery within an Enhanced Recovery After Surgery program.

METHODS

Randomized patient and assessor-blind controlled trial conducted in adult patients undergoing laparoscopic colorectal surgery within an Enhanced Recovery After Surgery program. Patients were assigned randomly to receive intraoperative goal-directed fluid therapy (goal-directed fluid therapy group) or fluid therapy based on traditional principles (control group). Primary postoperative ileus was the primary outcome.

RESULTS

One hundred twenty-eight patients were included and analyzed (goal-directed fluid therapy group: n = 64; control group: n = 64). The incidence of primary postoperative ileus was 22% in the goal-directed fluid therapy and 22% in the control group (relative risk, 1; 95% CI, 0.5 to 1.9; P = 1.00). Intraoperatively, patients in the goal-directed fluid therapy group received less intravenous fluids (mainly less crystalloids) but a greater volume of colloids. The increase of stroke volume and cardiac output was more pronounced and sustained in the goal-directed fluid therapy group. Length of hospital stay, 30-day postoperative morbidity, and mortality were not different.

CONCLUSIONS

Intraoperative goal-directed fluid therapy compared with fluid therapy based on traditional principles does not reduce primary postoperative ileus in patients undergoing laparoscopic colorectal surgery in the context of an Enhanced Recovery After Surgery program. Its previously demonstrated benefits might have been offset by advancements in perioperative care.

Active and Passive Optical Imaging Modality for Unobtrusive Cardiorespiratory Monitoring and Facial Expression Assessment

Because of their obvious advantages, active and passive optoelectronic sensor concepts are being investigated by biomedical research groups worldwide, particularly their camera-based variants. Such methods work noninvasively and contactless, and they provide spatially resolved parameter detection. We present 2 techniques: the active photoplethysmography imaging (PPGI) method for detecting dermal blood perfusion dynamics and the passive infrared thermography imaging (IRTI) method for detecting skin temperature distribution. PPGI is an enhancement of classical pulse oximetry. Approved algorithms from pulse oximetry for the detection of heart rate, heart rate variability, blood pressure-dependent pulse wave velocity, pulse waveform-related stress/pain indicators, respiration rate, respiratory variability, and vasomotional activity can easily be adapted to PPGI. Although the IRTI method primarily records temperature distribution of the observed object, information on respiration rate and respiratory variability can also be derived by analyzing temperature change over time, for example, in the nasal region, or through respiratory movement. Combined with current research areas and novel biomedical engineering applications (eg, telemedicine, tele-emergency, and telemedical diagnostics), PPGI and IRTI may offer new data for diagnostic purposes, including assessment of peripheral arterial and venous oxygen saturation (as well as their differences). Moreover, facial expressions and stress and/or pain-related variables can be derived, for example, during anesthesia, in the recovery room/intensive care unit and during daily activities. The main advantages of both monitoring methods are unobtrusive data acquisition and the possibility to assess vital variables for different body regions. These methods supplement each other to enable long-term monitoring of physiological effects and of effects with special local characteristics. They also offer diagnostic advantages for intensive care patients and for high-risk patients in a homecare/outdoor setting. Selected applications have been validated at our laboratory using optical PPGI and IRTI techniques in a stand-alone or hybrid configuration. Additional research and validation is required before these preliminary results can be introduced for clinical applications.

Passive Leg Raising: Simple and Reliable Technique to Prevent Fluid Overload in Critically ill Patients

Background:

Dynamic measures, the response to stroke volume (SV) to fluid loading, have been used successfully to guide fluid management decisions in critically ill patients. However, application of dynamic measures is often inaccurate to predict fluid responsiveness in patients with arrhythmias, ventricular dysfunction or spontaneously breathing critically ill patients. Passive leg raising (PLR) is a simple bedside maneuver that may provide an accurate alternative to guide fluid resuscitation in hypovolemic critically ill patients.

Methods:

Pertinent medical literature for fluid responsiveness in the critically ill patient published in English was searched over the past three decades, and then the search was extended as linked citations indicated.

Results:

Thirty-three studies including observational studies, randomized control trials, systemic review, and meta-analysis studies evaluating fluid responsiveness in the critically ill patient met selection criteria.

Conclusions:

PLR coupled with real-time SV monitors is considered a simple, noninvasive, and accurate method to determine fluid responsiveness in critically ill patients with high sensitivity and specificity for a 10% increase in SV. The adverse effect of albumin on the mortality of head trauma patients and chloride-rich crystalloids on mortality and kidney function needs to be considered when choosing the type of fluid for resuscitation.

Evaluation of the dynamic predictors of fluid responsiveness in dogs receiving goal-directed fluid therapy

OBJECTIVES

Goal-directed fluid therapy (GDFT) based on pulse pressure variation (PPV) was used in anaesthetized dogs undergoing abdominal surgeries. The aims were 1) to evaluate the success rate of the PPV ≥13% in detecting fluid responsiveness [delta stroke volume (ΔSV) ≥10%]; 2) to assess the correlation between PPV, systolic pressure variation (SPV), Plethysmograph Variability Index (PVI) and central venous pressure (CVP) and 3) to establish the threshold value for the PVI that would predict a PPV value of ≥13% and indirectly discriminate responders from nonresponders to fluid therapy.

STUDY DESIGN

Clinical, prospective, interventional study.

ANIMALS

A total of 63 client-owned dogs scheduled for abdominal procedures.

METHODS

PPV and SPV were calculated manually from the invasive blood pressure trace on the Datex monitor. PVI was recorded from the Masimo pulse oximeter. Fluid challenge (10 mL kg^-1 Compound Sodium Lactate) was performed when PPV was ≥13% and/or mean arterial pressure (MAP) < 60 mmHg. Fluid responsiveness was assessed by the transoesophageal Doppler probe. Cardiovascular parameters (heart rate, MAP, PPV, SPV, PVI, SV and if available, CVP) were measured before and after each fluid intervention.

RESULTS

PPV ≥ 13% reliably predicted fluid responsiveness in 82.9% of cases. There was positive correlation between PPV and SPV (r = 0.84%), PPV and logPVI (r = 0.46) as well as SPV and logPVI (r = 0.45). Noninvasive PVI value ≥13% should predict PPV threshold value (13%) with 97% sensitivity and 68% specificity. There was no statistically significant correlation between PPV and CVP.

CONCLUSIONS

PPV is a useful clinical tool to detect occult hypovolaemia and predict cardiovascular response to fluid challenge. Use of PPV is recommended as a part of GDFT in dogs undergoing abdominal procedures.

Effect of perioperative goal-directed hemodynamic therapy on postoperative recovery following major abdominal surgery-a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Goal-directed hemodynamic therapy (GDHT) has been used in the clinical setting for years. However, the evidence for the beneficial effect of GDHT on postoperative recovery remains inconsistent. The aim of this systematic review and meta-analysis was to evaluate the effect of perioperative GDHT in comparison with conventional fluid therapy on postoperative recovery in adults undergoing major abdominal surgery.

METHODS

Randomized controlled trials (RCTs) in which researchers evaluated the effect of perioperative use of GDHT on postoperative recovery in comparison with conventional fluid therapy following abdominal surgery in adults (i.e., >16 years) were considered. The effect sizes with 95% CIs were calculated.

RESULTS

Forty-five eligible RCTs were included. Perioperative GDHT was associated with a significant reduction in short-term mortality (risk ratio [RR] 0.75, 95% CI 0.61-0.91, p = 0.004, I ² = 0), long-term mortality (RR 0.80, 95% CI 0.64-0.99, p = 0.04, I ² = 4%), and overall complication rates (RR 0.76, 95% CI 0.68-0.85, p < 0.0001, I ² = 38%). GDHT also facilitated gastrointestinal function recovery, as demonstrated by shortening the time to first flatus by 0.4 days (95% CI -0.72 to -0.08, p = 0.01, I ² = 74%) and the time to toleration of oral diet by 0.74 days (95% CI -1.44 to -0.03, p < 0.0001, I ² = 92%).

CONCLUSIONS

This systematic review of available evidence suggests that the use of perioperative GDHT may facilitate recovery in patients undergoing major abdominal surgery.

Assessment of macro- and micro-oxygenation parameters during fractional fluid infusion: A pilot study

PURPOSE

The main goal of this study was to assess whether maximal fluid infusion improves both oxygen delivery (DO₂) and micro-circulatory parameters during hemodilution. The secondary objective was to assess the ability of baseline micro-circulatory parameters to predict oxygen consumption (VO₂) response following fluid infusion.

MATERIALS AND METHODS

In a postoperative cardiac ICU, patients received repeated fluid infusion until stroke volume (SV) was maximized. Before and after each fluid expansion, macro- (DO₂, VO₂) and micro-circulatory oxygenation parameters were recorded [central venous oxygen saturation (ScVO₂), blood lactate, difference in veno-arterial carbon dioxide tension (P(v-a)CO₂), somatic and cerebral oxygen saturation (rSO₂)]. Patients were classified as VO₂-Responders or VO₂-Non-Responders according to an increase in VO₂ above or below 15%, respectively.

RESULTS

After maximal fluid infusion, all patients showed improved macro- and micro-circulatory oxygenation parameters, but VO₂-Responders had lower values (especially for ScVO₂ and cerebral rSO₂). Only baseline ScVO₂ and cerebral rSO₂ were useful to predict the VO₂ response to maximal fluid infusion (ROC_AUC 0.80 (95% CI: 0.54-0.95, P=0.012) and 0.83 (95% CI: 0.57-0.96, P=0.001).

CONCLUSIONS

Maximal fluid infusion improves macro- and micro-circulatory oxygenation parameters. For VO₂-Responders, only ScVO₂ and cerebral rSO₂ could serve as markers of tissue hypoxia.

Effect of goal-directed therapy on outcome after esophageal surgery: A quality improvement study

Background

Goal-directed therapy (GDT) can reduce postoperative complications in high-risk surgery patients. It is uncertain whether GDT has the same benefits in patients undergoing esophageal surgery. Goal of this Quality Improvement study was to evaluate the effects of a stroke volume guided GDT on post-operative outcome.

Methods and findings

We compared the postoperative outcome of patients undergoing esophagectomy before (99 patients) and after (100 patients) implementation of GDT. There was no difference in the proportion of patients with a complication (56% vs. 54%, p = 0.82), hospital stay and mortality. The incidence of prolonged ICU stay (>48 hours) was reduced (28% vs. 12, p = .005) in patients treated with GDT. Secondary analysis of complication rate showed a decrease in pneumonia (29 vs. 15%, p = .02), mediastinal abscesses (12 vs. 3%, p = .02), and gastric tube necrosis (5% vs. 0%, p = .03) in patients treated with GDT. Patients in the GDT group received significantly less fluids but received more colloids.

Conclusions

The implementation of GDT during esophagectomy was not associated with reductions in overall morbidity, mortality and hospital length of stay. However, we observed a decrease in pneumonia, mediastinal abscesses, gastric tube necrosis, and ICU length of stay.

Enhanced recovery pathway in patients undergoing distal pancreatectomy: a case-matched study

BACKGROUND

Enhanced recovery (ER) pathways have improved outcomes across multiple surgical specialties, but reports concerning their application in distal pancreatectomy (DP) are lacking. The aim of this study was to assess compliance with an ER protocol and its impact on short-term outcomes in patients undergoing DP.

METHODS

Prospectively collected data were reviewed. One hundred consecutive patients undergoing DP were treated within an ER pathway comprising 18 care elements. Each patient was matched 1:1 with a patient treated with usual perioperative care. Match criteria were age, BMI, ASA score, lesion site, and type of disease.

RESULTS

Adherence to ER items ranged from 15% for intraoperative restrictive fluids to 100% for intraoperative warming, antibiotic and anti-thrombotic prophylaxis. Patients in ER group experienced earlier recovery of gastrointestinal function (2 vs. 3 days, p < 0.001), oral intake (2 vs. 4 days, p < 0.001), and suspension of intravenous infusions (3 vs. 5 days, p < 0.001). Overall morbidity was similar in the two groups (72% vs. 78%). Length of hospital stay (LOS) was reduced in ER patients without postoperative complications (6.7 ± 1.2 vs. 7.6 ± 1.6 days, p = 0.041).

CONCLUSIONS

An ER pathway for DP yielded an earlier postoperative recovery and shortened LOS in uneventful patients. Postoperative morbidity and readmissions were similar in both groups.

Goal-directed fluid restriction during brain surgery: a prospective randomized controlled trial

Background

The value of goal-directed fluid therapy in neurosurgical patients, where brain swelling is a major concern, is unknown. The aim of our study was to evaluate the effect of an intraoperative goal-directed fluid restriction (GDFR) strategy on the postoperative outcome of high-risk patients undergoing brain surgery.

Methods

High-risk patients undergoing brain surgery were randomly assigned to a usual care group (control group) or a GDFR group. In the GDFR group, (1) fluid maintenance was restricted to 3 ml/kg/h of a crystalloid solution and (2) colloid boluses were allowed only in case of hypotension associated with a low cardiac index and a high stroke volume variation. The primary outcome variable was ICU length of stay, and secondary outcomes were lactates at the end of surgery, postoperative complications, hospital length of stay, mortality at day 30, and costs.

Results

A total of 73 patients from the GDFR group were compared with 72 patients from the control group. Before surgery, the two groups were comparable. During surgery, the GDFR group received less colloid (1.9 ± 1.1 vs. 3.9 ± 1.6 ml/kg/h, p = 0.021) and less crystalloid (3 ± 0 vs. 5.0 ± 2.8 ml/kg/h, p < 0.001) than the control group. ICU length of stay was shorter (3 days [1–5] vs. 6 days [3–11], p = 0.001) and ICU costs were lower in the GDFR group. The total number of complications (46 vs. 99, p = 0.043) and the proportion of patients who developed one or more complications (19.2 vs. 34.7%, p = 0.034) were smaller in the GDFR group. Hospital length of stay and costs, as well as mortality at 30 day, were not significantly reduced.

Conclusion

In high-risk patients undergoing brain surgery, intraoperative GDFR was associated with a reduction in ICU length of stay and costs, and a decrease in postoperative morbidity.

Trial registration Chinese Clinical Trial Registry ChiCTR-TRC-13003583, Registered 20 Aug, 2013

Postoperative complications and clinical outcomes among patients undergoing thoracic and gastrointestinal cancer surgery: A prospective cohort study

Objective

This study sought to determine the influence of postoperative complications on the clinical outcomes of patients who underwent thoracic and gastrointestinal cancer surgery.

Methods

A prospective cohort study was conducted regarding 179 consecutive patients who received thorax or digestive tract surgery due to cancer and were admitted to an oncological intensive care unit. The Postoperative Morbidity Survey was used to evaluate the incidence of postoperative complications. The influence of postoperative complications on both mortality and length of hospital stay were also assessed.

Results

Postoperative complications were found for 54 patients (30.2%); the most common complications were respiratory problems (14.5%), pain (12.9%), cardiovascular problems (11.7%), infectious disease (11.2%), and surgical wounds (10.1%). A multivariate logistic regression found that respiratory complications (OR = 18.68; 95%CI = 5.59 - 62.39; p < 0.0001), cardiovascular problems (OR = 5.06, 95%CI = 1.49 - 17.13; p = 0.009), gastrointestinal problems (OR = 26.09; 95%CI = 6.80 - 100.16; p < 0.0001), infectious diseases (OR = 20.55; 95%CI = 5.99 - 70.56; p < 0.0001) and renal complications (OR = 18.27; 95%CI = 3.88 - 83.35; p < 0.0001) were independently associated with hospital mortality. The occurrence of at least one complication increased the likelihood of remaining hospitalized (log-rank test, p = 0.002).

Conclusions

Postoperative complications are frequent disorders that are associated with poor clinical outcomes; thus, structural and procedural changes should be implemented to reduce postoperative morbidity and mortality.

Goal-directed fluid therapy for reducing risk of surgical site infections following abdominal surgery - A systematic review and meta-analysis of randomized controlled trials

BACKGROUND AND OBJECTIVE

Surgical site infections (SSIs) become a key indicator of quality of care. This meta-analysis aimed to determine the effect of goal-directed fluid therapy (GDFT) on the risk of SSIs after abdominal surgery.

METHODS

MEDLINE, Embase, CINAHL, Scopus, the Cochrane Controlled Trials Register, and Cochrane Database of Systematic Reviews were searched for randomized controlled trials (RCTs), from inception to May 2016 that compared the incidence of SSIs in abdominal surgical patients with or without GDFT treatment. . Data were pooled and risk ratio (RR) as well as weighted mean differences (WMD) with their 95% confidence intervals (CI) was calculated using either fixed or random effects models, depending on heterogeneity (I²).

RESULTS

A total of 29 eligible RCTs with 5317 patients were included in this analysis. GDFT significantly reduced the incidence of SSIs after abdominal surgery. The pooled RR was 0.74 (95% CI: 0.63 to 0.86) with low heterogeneity (I² = 4%). Length of hospital stay was significantly reduced in the GDFT group (WMD: -1.16 days, 95% CI: -1.92 to -0.40, p = 0.003; I² = 81%).

CONCLUSION

This systematic review suggests that perioperative GDFT is associated with a reduction in the incidence of SSIs after abdominal surgery.

Beat-by-beat assessment of cardiac afterload using descending aortic velocity-pressure loop during general anesthesia: a pilot study

INTRODUCTION

Continuous cardiac afterload evaluation could represent a useful tool during general anesthesia (GA) to titrate vasopressor effect. Using beat to beat descending aortic pressure(P)/flow velocity(U) loop obtained from esophageal Doppler and femoral pressure signals might allow to track afterload changes. Methods We defined three angles characterizing the PU loop (alpha, beta and Global After-Load Angle (GALA)). Augmentation index (AIx) and total arterial compliance (Ctot) were measured via radial tonometry. Peripheral Vascular Resistances (PVR) were also calculated. Twenty patients were recruited and classified into low and high cardiovascular (CV) risk group. Vasopressors were administered, when baseline mean arterial pressure (MAP) fell by 20%. Results We studied 118 pairs of pre/post bolus measurements. At baseline, patients in the lower CV risk group had higher cardiac output (6.1 ± 1.7 vs 4.2 ± 0.6 L min; p = 0.005), higher Ctot (2.7 ± 1.0 vs 2.0 ± 0.4 ml/mmHg, p = 0.033), lower AIx and PVR (13 ± 10 vs 32 ± 11% and 1011 ± 318 vs 1390 ± 327 dyn s/cm⁵; p < 0.001 and p = 0.016, respectively) and lower GALA (41 ± 15 vs 68 ± 6°; p < 0.001). GALA was the only PU Loop parameter associated with Ctot, AIx and PVR. After vasopressors, MAP increase was associated with a decrease in Ctot, an increase in AIx and PVR and an increase in alpha, beta and GALA (p < 0.001 for all). Changes in GALA and Ctot after vasopressors were strongly associated (p = 0.004). Conclusions PU Loop assessment from routine invasive hemodynamic optimization management during GA and especially GALA parameter could monitor cardiac afterload continuously in anesthetized patients, and may help clinicians to titrate vasopressor therapy.

Swedish surgical outcomes study (SweSOS): An observational study on 30-day and 1-year mortality after surgery

BACKGROUND

The European Surgical Outcomes Study (EuSOS) revealed large variations in outcomes among countries. In-hospital mortality and ICU admission rates in Sweden were low, going against the assumption that access to ICU improves outcome. Long-term mortality was not reported in EuSOS and is generally poorly described in the current literature.

OBJECTIVE

To describe the characteristics of the Swedish subset of EuSOS and identify predictors of short and long-term mortality after surgery.

DESIGN

An observational cohort study.

SETTING

Six universities and two regional hospitals in Sweden.

PATIENTS

A cohort of 1314 adult patients scheduled for surgery between 4 April and 11 April 2011.

MAIN OUTCOME MEASURES

30-day and 1-year mortality.

RESULTS

A total of 303 patients were lost to follow-up, leaving 1011 for analysis; 69% of patients were classified as American Society of Anesthesiologists' physical status 1 or 2, and 68% of surgical procedures were elective. The median length of stay in postanaesthesia care units (PACUs) was 175 min (interquartile range 110-270); 6.6% of patients had PACU length of stay of more than 12 h and 3.6% of patients were admitted to the ICU postoperatively. Thirty-day mortality rate was 1.8% [95% confidence interval (CI) 1.0-2.6] and 8.5% (CI 6.8-10.2) at 1 year (n = 18 and 86). The risk of death was higher than in an age and sex-matched population after 30 days (standardised mortality ratio 10.0, CI 5.9-15.8), and remained high after 1 year (standardised mortality ratio 3.9, CI 3.1-4.8). Factors predictive of 30-day mortality were age, American Society of Anesthesiologists' physical status, number of comorbidities, urgency of surgery and ICU admission. For 1-year mortality, age, number of comorbidities and urgency of surgery were independently predictive. ICU admission and long stay in PACU were not significant predictors of long-term mortality.

CONCLUSION

Mortality rate increased almost five-fold at 1 year compared with 30-day mortality after surgery, demonstrating a significantly sustained long-term risk of death in this surgical population. In Sweden, factors associated with long-term postoperative mortality were age, number of comorbidities and surgical urgency.

Perioperative fluid management: From physiology to improving clinical outcomes

Perioperative fluid management is a key component in the care of the surgical patient. It is an area that has seen significant changes and developments, however there remains a wide disparity in practice between clinicians. Historically, patients received large volumes of intravenous fluids perioperatively. The concept of goal directed therapy was then introduced, with the early studies showing significant improvements in morbidity and mortality. The current focus is on fluid therapy guided by an individual patient's physiology. A fluid challenge is commonly performed as part of an assessment of a patient's fluid responsiveness. There remains wide variation in how clinicians perform a fluid challenge and this review explores the evidence for how to administer an effective challenge that is both reliable and reproducible. The methods for monitoring cardiac output have evolved from the pulmonary artery catheter to a range of less invasive techniques. The different options that are available for perioperative use are considered. Fluid status can also be assessed by examining the microcirculation and the importance of recognising the possibility of a lack of coherence between the macro and microcirculation is discussed. Fluid therapy needs to be targeted to specific end points and individualised. Not all patients who respond to a fluid challenge will necessarily require additional fluid administration and care should be aimed at identifying those who do. This review aims to explain the underlying physiology and describe the evidence base and the changes that have been seen in the approach to perioperative fluid therapy.

Accuracy of Cardiac Output by Nine Different Pulse Contour Algorithms in Cardiac Surgery Patients: A Comparison with Transpulmonary Thermodilution

Objective. Today, there exist several different pulse contour algorithms for calculation of cardiac output (CO). The aim of the present study was to compare the accuracy of nine different pulse contour algorithms with transpulmonary thermodilution before and after cardiopulmonary bypass (CPB). Methods. Thirty patients scheduled for elective coronary surgery were studied before and after CPB. A passive leg raising maneuver was also performed. Measurements included CO obtained by transpulmonary thermodilution (CO_TPTD) and by nine pulse contour algorithms (CO_X1–9). Calibration of pulse contour algorithms was performed by esophageal Doppler ultrasound after induction of anesthesia and 15 min after CPB. Correlations, Bland-Altman analysis, four-quadrant, and polar analysis were also calculated. Results. There was only a poor correlation between CO_TPTD and CO_X1–9 during passive leg raising and in the period before and after CPB. Percentage error exceeded the required 30% limit. Four-quadrant and polar analysis revealed poor trending ability for most algorithms before and after CPB. The Liljestrand-Zander algorithm revealed the best reliability. Conclusions. Estimation of CO by nine different pulse contour algorithms revealed poor accuracy compared with transpulmonary thermodilution. Furthermore, the less-invasive algorithms showed an insufficient capability for trending hemodynamic changes before and after CPB. The Liljestrand-Zander algorithm demonstrated the highest reliability. This trial is registered with NCT02438228 (ClinicalTrials.gov).

Central venous pressure: soon an outcome-associated matter

PURPOSE OF REVIEW

Central venous pressure (CVP) alone has so far not found a place in outcome prediction or prediction of fluid responsiveness. Improved understanding of the interaction between mean systemic pressure (Pms) and CVP has major implications for evaluating volume responsiveness, heart performance and potentially patient outcomes.

RECENT FINDINGS

The literature review substantiates that CVP plays a decisive role in causation of operative haemorrhage and renal failure. The review details CVP as a variable integral to cardiovascular control in its dual role of distending the diastolic right ventricle and opposing venous return.

SUMMARY

The implication for practice is in the regulation of the circulation. It is demonstrated that control of the blood pressure and cardiac output/venous return calls upon regulation of the volume state (Pms), the heart performance (Eh) and the systemic vascular resistance. Knowledge of the CVP is required to calculate all three.

Implementation of goal-directed fluid therapy during hip revision arthroplasty: a matched cohort study

Background

Several randomized controlled trials (RCTs) have demonstrated that intraoperative goal-directed fluid therapy (GDFT) can decrease postsurgical complications in patients undergoing major abdominal surgery. However, very few studies have demonstrated the value of goal-directed therapy (GDT) in patients undergoing orthopaedic surgery and confirmed it is as useful in real-life conditions. Therefore, we initiated a GDFT implementation programme in patients undergoing hip revision arthroplasty in order to assess its effects on postoperative complications (e.g. infection, cardiac, neurological, renal) (primary outcome) and hospital and intensive care unit (ICU) length of stay (secondary outcomes).

Methods

We developed a GDFT protocol for the haemodynamic management of patients undergoing hip revision arthroplasty. The GDFT protocol was based on continuous monitoring and optimization of stroke volume during the surgical procedure. From December 2012 and for a period of 17 months, 130 patients were treated according to the GDFT protocol (GDFT group). The pre-, intra-, and postoperative characteristics of patients from the GDFT group were compared to those of 130 historical matched patients (control group) who had the same surgery between January 2011 and August 2012.

Results

Patients from the GDFT and from the control group were comparable in terms of age, comorbidities, and P-POSSUM score. Duration of anaesthesia and surgery were also comparable. The GDFT group had a significantly lower morbidity rate (49.2 vs. 66.9%; p = 0.006) and a shorter median hospital length of stay (11 days (9–15) vs. 9 days (8–12); p = 0.003) than the control group. Patients from the control group post-anaesthesia care unit (PACU)/ICU stayed significantly longer at PACU/ICU than patients from the GDFT group (control group vs. GDFT group, 960 min (360–1210) vs. 400 min (207–825); p < 0.001) Patients from the GDFT group received less crystalloids but more colloids during surgery. They also received more often inotropic therapy.

Conclusions

In patients undergoing hip revision arthroplasty, the implementation of GDT as a new standard operating procedure was successful and associated with reduced postsurgical complications, most importantly a reduction in postoperative bleeding as well as hospital and ICU stay.

Trial registration

ClinicalTrials.gov, NCT01753050

Electronic supplementary material

The online version of this article (doi:10.1186/s13741-016-0056-x) contains supplementary material, which is available to authorized users.

Correlation of the ratio of caudal vena cava diameter and aorta diameter with systolic pressure variation in anesthetized dogs

OBJECTIVE

To evaluate the correlation coefficient of the ratio between diameter of the caudal vena cava (CVC) and diameter of the aorta (Ao) in dogs as determined ultrasonographically with systolic pressure variation (SPV).

ANIMALS

14 client-owned dogs (9 females and 5 males; mean ± SD age, 73 ± 40 months; mean body weight, 22 ± 7 kg) that underwent anesthesia for repair of skin wounds.

PROCEDURES

Anesthesia was induced. Controlled mechanical ventilation with a peak inspiratory pressure of 8 cm H2O was immediately started, and SPV was measured. During a brief period of suspension of ventilation, CVC-to-Ao ratio was measured on a transverse right-lateral intercostal ultrasonographic image obtained at the level of the porta hepatis. When the SPV was ≥ 4 mm Hg, at least 1 bolus (3 to 4 mL/kg) of Hartmann solution was administered IV during a 1-minute period. Bolus administration was stopped and the CVC-to-Ao ratio measured when SPV was < 4 mm Hg. Correlation coefficient analysis was performed.

RESULTS

28 measurements were obtained. The correlation coefficient was 0.86 (95% confidence interval, 0.72 to 0.93). Mean ± SD SPV and CVC-to-Ao ratio before bolus administration were 7 ± 2 mm Hg and 0.52 ± 0.16, respectively. Mean ± SD SPV and CVC-to-Ao ratio after bolus administration were 2 ± 0.6 mm Hg and 0.91 ± 0.13, respectively.

CONCLUSIONS AND CLINICAL RELEVANCE

In this study, the CVC-to-Ao ratio was a feasible, noninvasive ultrasonographically determined value that correlated well with SPV.

Haemodynamic coherence in perioperative setting

Over the last decade, there has been an increased interest in the use of goal-directed therapy (GDT) in patients undergoing high-risk surgery, and various haemodynamic monitoring tools have been developed to guide perioperative care. Both the complexity of the patient and surgical procedure need to be considered when deciding whether GDT will be beneficial. Ensuring optimum tissue perfusion is paramount in the perioperative period and relies on the coherence between both macrovascular and microvascular circulations. Although global haemodynamic parameters may be optimised with the use of GDT, microvascular impairment can still persist. This review will provide an overview of both haemodynamic optimisation and microvascular assessment in the perioperative period.

Could the Use of an Enhanced Recovery Protocol in Laparoscopic Donor Nephrectomy be an Incentive for Live Kidney Donation?

Introduction and Background: Gastrointestinal (GI) recovery after major abdominal surgery can be delayed from an ongoing need for narcotic analgesia thereby prolonging hospitalization. Enhanced recovery after surgery (ERAS) is a multimodal perioperative care pathway designed to facilitate early recovery after major surgery by maintaining preoperative body composition and physiological organ function and modifying the stress response induced by surgical exposure. Enhanced recovery programs (ERPs) in colorectal surgery have decreased the duration of postoperative ileus and the hospital stay while showing equivalent morbidity, mortality, and readmission rates in comparison to the traditional standard of care. This study is a pilot trial to evaluate the benefits of ERAS protocols in living kidney donors undergoing laparoscopic nephrectomy.

Methods: This is a single-center, non-randomized, retrospective analysis comparing the outcomes of the first 40 live kidney donors subjected to laparoscopic nephrectomy under the ERAS protocol to 40 donors operated prior to ERAS with traditional standard of care. Our ERAS protocol includes reduced duration of fasting with preoperative carbohydrate loading, intraoperative fluid restriction to 3 ml/kg/hr, target urine output of 0.5 ml/kg/hr, use of subfascial Exparel injection (bupivacaine liposome suspension), and postoperative narcotic-free pain regimen with acetaminophen, ketorolac, or tramadol. Short-term patient outcomes were compared using Pearsons’s Chi-Squared test for categorical variables and the Kruskal-Wallis test for continuous variables. Additionally, a multivariate analysis was conducted to evaluate factors influencing patient length of stay and likelihood of readmission.

Results: ERAS protocol reduced the postoperative median length of stay decreased from 2.0 to 1.0 days (p=0.001). Overall pain scores were significantly lower in the ERAS group (peak pain score 6.0 vs. 8.00, p< 0.001; morning after surgery pain score 3.0 vs. 7.0, p=0.001; lowest pain score 0.0 vs. 2.0, p=0.016) despite the absence of postoperative narcotics. The average duration of surgery was shorter in the ERAS group (248 vs. 304 minutes, p<0.001). The average amount of intraoperative fluid used was significantly lower in the ERAS group (2500 ml vs. 3525 ml, p<0.001) without affecting the donor renal function. The incidence of delayed graft function was similar in the two groups (p=0.541). A trend toward lower readmission was noted with the ERAS protocol (12.8% vs. 27.5%, p=0.105). GI dysfunction was the most common reason for readmission.

Conclusion: Application of an ERAS protocol in a laparoscopic living donor nephrectomy was associated with reduced length of hospitalization and improved pain scores related likely to intraoperative use of subfascial Exparel and a shorter duration of ileus. Restricted use of intraoperative fluids prevents excessive third spacing and bowel edema, enhancing gut recovery without adversely impacting recipient graft function. This study suggests that ERAS has the potential to enhance the advantages of laparoscopic surgery for live kidney donation through optimizing donor outcomes and perioperative patient satisfaction.

Post-operative consequences of hemodynamic optimization

Hemodynamic optimization begins with a medical assessment to identify the high-risk patients. This stratification is needed to customize the choice of hemodynamic support that is best adapted to the patient's level of risk, integrating the use of the least invasive procedures. The macro-circulatory hemodynamic approach aims to maintain a balance between oxygen supply (DO₂) and oxygen demand (VO₂). Volume replacement plays a crucial role based on the titration of fluid boluses according to their effect on measured stroke volume or indices of preload dependency. Good function of the microcirculatory system is the best guarantee to achieve this goal. An assessment of the DO₂/VO₂ ratio is needed for guidance in critical situations where tissue hypoxia may occur. Overall, all of these strategies are based on objective criteria to guide vascular replacement and/or tissue oxygenation in order to improve the patient's post-operative course by decreasing morbidity and hospital stay.

Goal directed fluid therapy decreases postoperative morbidity but not mortality in major non-cardiac surgery: a meta-analysis and trial sequential analysis of randomized controlled trials

BACKGROUND AND AIMS

Optimum perioperative fluid administration may improve postoperative outcome after major surgery. This meta-analysis and systematic review has been aimed to determine the effect of dynamic goal directed fluid therapy (GDFT) on postoperative morbidity and mortality in non-cardiac surgical patients.

MATERIAL AND METHODS

Meta-analysis of published prospective randomized controlled trials where GDFT based on non-invasive flow based hemodynamic measurement has been compared with a standard care. Data from 41 prospective randomized trials have been included in this study.

RESULTS

Use of GDFT in major surgical patients does not decrease postoperative hospital/30-day mortality (OR 0.70, 95 % CI 0.46-1.08, p = 0.11) length of post-operative hospital stay (SMD -0.14; 95 % CI -0.28, 0.00; p = 0.05) and length of ICU stay (SMD -0.12; 95 % CI -0.28, 0.04; p = 0.14). However, number of patients having at least one postoperative complication is significantly lower with use of GDFT (OR 0.57; 95 % CI 0.43, 0.75; p < 0.0001). Abdominal complications (p = 0.008), wound infection (p = 0.002) and postoperative hypotension (p = 0.04) are also decreased with used of GDFT as opposed to a standard care. Though patients who received GDFT were infused more colloid (p < 0.0001), there is no increased risk of heart failure or pulmonary edema and renal failure.

CONCLUSION

GDFT in major non- cardiac surgical patients has questionable benefit over a standard care in terms of postoperative mortality, length of hospital stay and length of ICU stay. However, incidence of all complications including wound infection, abdominal complications and postoperative hypotension is reduced.