Fluid management of patients undergoing abdominal surgery – more questions than answers *

Perioperative care in bariatric surgery in the context of the ACERTO project: reality versus surgeons assumptions in a Cuiabá hospital

Objective:

to assess the level of knowledge among bariatric surgeons, about the recommendations of the ACERTO Project, correlating their assumptions on their perioperative prescriptions and the reality, according to the patients charts.

Method:

we conducted a prospective, longitudinal, observational study comparing the assumptions of bariatric surgeons obtained through responses on a specific questionnaire with the reality found in clinical data from the hospital records. We analyzed the following variables: preoperative fasting, early postoperative feeding, intravenous hydration, perioperative antibiotic prophylaxis, use of abdominal drains, type of analgesia, and prophylaxis of nausea and vomiting. We confronted the responses of seven surgeons with data from 200 records of patients undergoing gastroplasty for morbid obesity.

Results:

all interviewed surgeons knew the ACERTO Project. Five (72%) responded that they followed the protocol thoroughly. The median time of preoperative fasting found in the records was higher than the reported by the surgeons (p<0.05). Early postoperative feeding was prescribed for 96.5% of cases. The median volume of intravenous fluids prescribed in the first 24 hours was 4000ml, which was consistent with the interviews. There were no differences between the response in the questionnaire and the findings in the hospital records in relation to antibiotic prophylaxis, use of catheters and drains, analgesia and prophylaxis of nausea and vomiting.

Conclusion:

the ACERTO Project was well practiced among the surveyed surgeons. There was a good correlation between their assumptions and the reality in perioperative care of patients undergoing bariatric surgery. However, there was a significant difference in preoperative fasting time.

Enhanced recovery after surgery for hip and knee arthroplasty: a systematic review and meta-analysis

Objectives

To collect data of randomised controlled trials (RCTs) and clinical controlled trials (CCTs) for evaluating the effects of enhanced recovery after surgery on postoperative recovery of patients who received total hip arthroplasty (THA) or total knee arthroplasty (TKA).

Methods

Relevant, published studies were identified using the following key words: arthroplasty, joint replacement, enhanced recovery after surgery, fast track surgery, multi-mode analgesia, diet management, or steroid hormones. The following databases were used to identify the literature consisting of RCTs or CCTs with a date of search of 31 December 2016: PubMed, Cochrane, Web of knowledge, Ovid SpringerLink and EMBASE. All relevant data were collected from studies meeting the inclusion criteria. The outcome variables were postoperative length of stay (LOS), 30-day readmission rate, and total incidence of complications. RevMan5.2. software was adopted for the meta-analysis.

Results

A total of 10 published studies (9936 cases) met the inclusion criteria. The cumulative data included 4205 cases receiving enhanced recovery after surgery (ERAS), and 5731 cases receiving traditional recovery after surgery (non-ERAS). The meta-analysis showed that LOS was significantly lower in the ERAS group than in the control group (non-ERAS group) (p<0.01), and there were fewer incidences of complications in the ERAS group than in the control group (p=0.03). However, no significant difference was found in the 30-day readmission rate (p=0.18).

Conclusions

ERAS significantly reduces LOS and incidence of complications in patients who have had THA or TKA. However, ERAS does not appear to significantly impact 30-day readmission rates.

Perioperative fluid restriction in major abdominal surgery: systematic review and meta-analysis of randomized, clinical trials

BACKGROUND

Fluid management is a fundamental component of surgical care. Recently, there has been considerable interest in perioperative fluid restriction as a method of facilitating recovery following elective major surgery. A number of randomized trials have addressed the issue in various surgical specialities, and a recent meta-analysis proposed uniform definitions regarding fluid amount as well as examining fluid restriction in patients undergoing colonic resection.

METHODS

Medline, Embase, trial registries, conference proceedings, and article reference lists were searched to identify randomized, controlled trials of perioperative fluid restriction versus "standard" perioperative fluid management, as per definitions formulated previously. All of the studies involved patients undergoing colonic resection. The primary outcome measure was postoperative morbidity. Secondary endpoints included mortality, renal failure, time to first flatus, and length of hospital stay. A random effects model was applied.

RESULTS

Seven randomized, controlled trials with a total of 856 patients investigating standard versus restrictive fluid regimes, as denoted by the definitions, were included. Perioperative fluid restriction had no effect on the risk of postoperative complications (OR 0.49 (95 % confidence interval (CI) 0.2-1.18; P = 0.101). There was no detectable effect on death and fluid restriction did not reduce hospital stay (Pooled weighted mean difference -0.25; 95 % CI 0.72-0.21; P = 0.29).

CONCLUSIONS

Perioperative fluid restriction does not significantly reduce the risk of complications following major abdominal surgery. Furthermore, it does not appear to reduce length of hospital stay.

[Non-cardiac surgery in patients with cardiac disease]

BACKGROUND

Patients with cardiac disease have a higher incidence of cardiovascular events after non-cardiac surgery than those without such disease. This paper provides an overview of perioperative examinations and treatment.

MATERIAL AND METHODS

Own experience and systematic literature search through work with European guidelines constitute the basis for recommendations given in this article.

RESULTS

Beta-blockers should not be discontinued before surgery. High-risk patients may benefit from beta-blockers administered before major non-cardiac surgery. Slow dose titration is recommended. Echocardiography should be performed before preoperative beta-blockade to exclude latent heart failure. Statins should be considered before elective surgery and coronary intervention (stenting or surgery) before high-risk surgery. Otherwise, interventions should be evaluated irrespective of planned non-cardiac surgery. Patients with unstable coronary syndrome should only undergo non-cardiac surgery on vital indications. Neuraxial techniques are optimal for postoperative pain relief and thus for postoperative mobilization. Thromboprophylaxis is important, but increases the risk of epidural haematoma and requires systematic follow-up with respect to diagnostics and treatment.

INTERPRETATION

Little evidence supports the use of different anaesthetic methods in cardiac patients that undergo non-cardiac surgery than in other patients. Stable circulation, sufficient oxygenation, good pain relief, thromboprophylaxis, enteral nutrition and early mobilization are important factors for improving the perioperative course. Close cooperation between anaesthesiologist, surgeon and cardiologist improves logistics and treatment.

Diferença entre volume de fluidos cristaloides intravenosos prescritos e infundidos em pacientes no pós-operatório precoce

OBJETIVO: O objetivo deste trabalho foi auditar a real quantidade de fluídos cristalóides infundidos por via intravenosa em pacientes submetidos a operações abdominais de grande porte num hospital universitário. MÉTODOS: Computou-se a carga hídrica total (CHT) de fluidos cristalóides intravenosos infundida diariamente do 1º ao 4º dia de PO em 31 pacientes submetidos à operações de grande porte. Comparou-se a CHT com a carga hídrica prescrita (CHP) pelo médico. A CHT foi definida como a somatória da CHP acrescida de diluentes e medicações intravenosas. O protocolo do serviço recomendava a hidratação venosa no peri-operatório entre 30 e 50 mL/Kg/dia em pacientes com prescrição de jejum oral. A comparação entre CHT e CHP foi realizada em todos os dias de pós-operatório pelo teste t pareado. Estabeleceu-se em 5% o nível de significância estatística. RESULTADOS: A CHT infundida do 1º ao 4ºdia de pós-operatório foi de 12,8 (6,4-17,5) L. Desse total, 9,5 litros (74,3%) corresponderam a CHP e 3,3 L (25,7%) a diluentes e medicações venosas. Em todos os dias de pós-operatório a CHT foi significativamente maior que a CHP (p<0.001). Até o 3º dia de PO os pacientes receberam uma CHT superior a 50 mL/kg/dia. CONCLUSÃO: Conclui-se que a prescrição médica não contém o real volume de fluidos cristalóides intravenosos infundido. O volume de diluentes e medicações intravenosas pode chegar a 25% da carga hídrica prescrita.

Latest developments in peri-operative monitoring of the high-risk major surgery patient

Peri-operative monitoring technology has made great strides in the last 20 years with the introduction of minimally invasive devices to measure inter alia stroke volume, cardiac output, depth of anaesthesia and cerebral and tissue oxygen monitoring. Despite these technological advances, peri-operative management of the high risk major surgery patient has remained virtually unchanged. The vast majority of patients undergo a pre-operative assessment which is neither designed to quantify functional capacity nor predict outcome. Anaesthetists then usually monitor these patients using the same technology (e.g. pulse oximetry (SpO2), invasive systemic BP and CVP, end tidal carbon dioxide (etCO2) and anaesthetic agent monitoring) that was available in the early 1980s. Conventional intra-operative management can result in occult low levels of blood flow and oxygen delivery that lead to complications that only occur days or weeks following surgery and give false re-assurance to the anaesthetist that he or she is doing a "good job". Post-operative management then often takes place in an environment with reduced levels of both monitoring equipment and staff expertise. It is perhaps not surprising that outcome still remains poor in high-risk patients.(1) In this review, we will briefly describe the role of peri-operative optimization, some of the available monitors and indicate how their combined use might be beneficial in managing the high-risk surgical patient. We believe that although there is now evidence to suggest that the use of individual new monitors (such as assessment of fluid status, depth of anaesthesia, tissue oxygenation and blood flow) can influence outcome, it will only be their combination that will radically improve the peri-operative management and outcome of high-risk surgical patients. It is a matter of some urgency that large scale, prospective and collaborative studies be designed, funded and executed to prove or disprove this hypothesis.

Perioperative hemodynamic monitoring with transesophageal Doppler technology

Invasive cardiac output (CO) monitoring, traditionally performed with transpulmonary thermodilution techniques, is usually reserved for high-risk patients because of the inherent risks of these methods. In contrast, transesophageal Doppler (TED) technology offers a safe, quick, and less invasive method for routine measurements of CO. After esophageal insertion and focusing of the probe, the Doppler beam interrogates the descending aortic blood flow. On the basis of the measured frequency shift between the emitted and received ultrasound frequency, blood flow velocity is determined. From this velocity, combined with the simultaneously measured systolic ejection time, CO and other advanced hemodynamic variables can be calculated, including estimations of preload, afterload, and contractility. Numerous studies have validated TED-derived CO against reference methods. Although the agreement of CO values between TED and the reference methods is limited (95% limits of agreement: median 4.2 L/min, interquartile range 3.3-5.0 L/min), TED has been shown to accurately follow changes of CO over time, making it a useful device for trend monitoring. TED can be used to guide perioperative intravascular volume substitution and therapy, with vasoactive or inotropic drugs. Various studies have demonstrated a reduced postoperative morbidity and shorter length of hospital stay in patients managed with TED compared with conventional clinical management, suggesting that it may be a valuable supplement to standard perioperative monitoring. We review not only the technical basis of this method and its clinical application but also its limitations, risks, and contraindications.

Meta-analysis of standard, restrictive and supplemental fluid administration in colorectal surgery

BACKGROUND

Optimal fluid therapy for colorectal surgery remains uncertain.

METHODS

A simple model was applied to define standard, restrictive and supplemental fluid administration. These definitions enabled pooling of data from different trials. Randomized controlled trials on fluid amount (standard versus restrictive or supplemental amount) and on guidance for fluid administration (goal-directed fluid therapy by oesophageal Doppler-derived variables versus conventional haemodynamic variables) in patients with colorectal resection were eligible for inclusion. The primary outcome measure was postoperative morbidity. Secondary endpoints were mortality, cardiopulmonary morbidity, wound infection, anastomotic failure, recovery of bowel function and hospital stay. A random-effects model was applied.

RESULTS

Nine randomized controlled trials were included. Restrictive fluid amount (odds ratio (OR) 0.41 (95 per cent confidence interval (c.i.) 0.22 to 0.77); P = 0.005) and goal-directed fluid therapy by means of oesophageal Doppler-derived variables (OR 0.43 (95 per cent c.i. 0.26 to 0.71); P = 0.001) significantly reduced overall morbidity. There were no significant differences in the secondary endpoints analysed.

CONCLUSION

Using standardized definitions, this meta-analysis suggests that restrictive rather than standard fluid amount according to current textbook opinion, and goal-directed fluid therapy rather than fluid therapy guided by conventional haemodynamic variables, reduce morbidity after colorectal resection.

Goal-directed fluid management based on pulse pressure variation monitoring during high-risk surgery: a pilot randomized controlled trial

INTRODUCTION

Several studies have shown that maximizing stroke volume (or increasing it until a plateau is reached) by volume loading during high-risk surgery may improve post-operative outcome. This goal could be achieved simply by minimizing the variation in arterial pulse pressure (deltaPP) induced by mechanical ventilation. We tested this hypothesis in a prospective, randomized, single-centre study. The primary endpoint was the length of postoperative stay in hospital.

METHODS

Thirty-three patients undergoing high-risk surgery were randomized either to a control group (group C, n = 16) or to an intervention group (group I, n = 17). In group I, deltaPP was continuously monitored during surgery by a multiparameter bedside monitor and minimized to 10% or less by volume loading.

RESULTS

Both groups were comparable in terms of demographic data, American Society of Anesthesiology score, type, and duration of surgery. During surgery, group I received more fluid than group C (4,618 +/- 1,557 versus 1,694 +/- 705 ml (mean +/- SD), P < 0.0001), and deltaPP decreased from 22 +/- 75 to 9 +/- 1% (P < 0.05) in group I. The median duration of postoperative stay in hospital (7 versus 17 days, P < 0.01) was lower in group I than in group C. The number of postoperative complications per patient (1.4 +/- 2.1 versus 3.9 +/- 2.8, P < 0.05), as well as the median duration of mechanical ventilation (1 versus 5 days, P < 0.05) and stay in the intensive care unit (3 versus 9 days, P < 0.01) was also lower in group I.

CONCLUSION

Monitoring and minimizing deltaPP by volume loading during high-risk surgery improves postoperative outcome and decreases the length of stay in hospital.

TRIAL REGISTRATION

NCT00479011.

Prise en charge anesthésique de l'œsophagectomie: avancées et perspectives

Oesophagectomy is still characterized by a high postoperative mortality and respiratory morbidity. Nevertheless, epidemiological, medical and surgical advances have improved the management of this surgical procedure. The anaesthesiologist influence is present at each level, from the preoperative evaluation to the management of postoperative complications. The preoperative period is improved by the use of assessment scores, the better knowing of respiratory risk factors and of the neoadjuvant therapy adverse effects. The main objective of the operative period is to ensure a rapid weaning procedure and stability of the respiratory and haemodynamic functions, warranting the anastomotic healing. The interest of the association between respiratory rehabilitation and thoracic epidural analgesia is highlighted in the postoperative period. The management of postoperative complications, mainly represented by respiratory failure and anastomotic leakages, requires a multidisciplinary analysis. The potential interest of non-invasive ventilation and of the modulation of postoperative inflammatory response needs further investigation.