Randomized clinical trial of gut-specific nutrients in critically ill surgical patients

Factors associated with early postoperative feeding: An observational study in a colorectal surgery population

BACKGROUND AND AIMS

Early post-operative feeding is recommended within enhanced recovery after surgery programmes. This study aimed to describe post-operative feeding patterns and associated factors among patients following colorectal surgery, using a post-hoc analysis of observational data from a previous RCT on chewing gum after surgery.

METHODS

Data from 301 participants (59% male, median age 67 years) were included. Amounts of meals consumed on post-operative days (POD) 1-5 were recorded as: none, a quarter, half, three-quarters, all. 'Early' consumers were those who ate ≥a quarter of a meal on POD1. 'Early' tolerance was the consumption of at least half of three meals on POD1 or 2 without vomiting. Exploration of selected peri-operative factors with early feeding and tolerance were assessed using logistic regression.

RESULTS

222 people (73.8%) consumed solid food early, and 109 people (36.2%) tolerated solid food early. Several factors were associated with postoperative feeding: provision of pre-operative bowel preparation was associated with delayed consumption [odds ratio (OR) 0.34, 95% confidence interval (CI) 0.14-0.83] and tolerance (OR 0.35, 95% CI 0.16-0.81) of food; and laparoscopic/laparoscopic assisted (vs. open/converted to open surgery) was associated with early tolerance of food (OR 1.99, 95% CI 1.17-3.39).

CONCLUSIONS

While three-quarters of the study population ate solid food early, only one-third tolerated solid food early. Findings suggest that bowel preparation and surgery type are factors warranting further investigation in future studies to improve uptake of early post-operative feeding.

Feasibility of a novel exercise prehabilitation programme in patients scheduled for elective colorectal surgery: a feasibility randomised controlled trial

Background and objectives

To investigate the feasibility of delivering a functional exercise-based prehabilitation intervention and its effects on postoperative length of hospital stay, preoperative physical functioning and health-related quality of life in elective colorectal surgery.

Materials and methods

In this randomised controlled feasibility trial, 22 elective colorectal surgery patients were randomly assigned to exercise prehabilitation (n = 11) or standard care (n = 11). Feasibility of delivering the intervention was assessed based on recruitment and compliance to the intervention. Impact on postoperative length of hospital stay and complications, preoperative physical functioning (timed up and go test, five times sit to stand, stair climb test, handgrip dynamometry and 6-min walk test) and health-related quality of life were also assessed.

Results

Over 42% of patients (84/198) screened were deemed ineligible for prehabilitation due to insufficient time existing prior to scheduled surgery. Of those who were eligible, approximately 18% consented to the trial. Median length of hospital stay was 8 [range 6–27] and 10 [range 5–12] days respectively for the standard care and prehabilitation groups. Patterns towards preoperative improvements for the timed up and go test, stair climb test and 6-min walk test were observed for all participants receiving prehabilitation but not standard care.

Conclusions

Despite prehabilitation appearing to convey positive benefits on physical functioning, short surgical wait times and patient engagement represent major obstacles to implementing exercise prehabilitation programmes in colorectal cancer patients.

Electronic supplementary material

The online version of this article (10.1007/s00520-019-05098-0) contains supplementary material, which is available to authorized users.

Challenge to the Intestinal Mucosa During Sepsis

Sepsis is a complex of life-threating organ dysfunction in critically ill patients, with a primary infectious cause or through secondary infection of damaged tissues. The systemic consequences of sepsis have been intensively examined and evidences of local alterations and repercussions in the intestinal mucosal compartment is gradually defining gut-associated changes during sepsis. In the present review, we focus on sepsis-induced dysfunction of the intestinal barrier, consisting of an increased permeability of the epithelial lining, which may facilitate bacterial translocation. We discuss disturbances in intestinal vascular tonus and perfusion and coagulopathies with respect to their proposed underlying molecular mechanisms. The consequences of enzymatic responses by pancreatic proteases, intestinal alkaline phosphatases, and several matrix metalloproteases are also described. We conclude our insight with a discussion on novel therapeutic interventions derived from crucial aspects of the gut mucosal dynamics during sepsis.

Microbial cell preparation in enteral feeding in critically ill patients: A randomized, double-blind, placebo-controlled clinical trial

Gut failure is a common condition in critically ill patients in the intensive care unit (ICU). Enteral feeding is usually the first line of choice for nutrition support in critically ill patients. However, enteral feeding has its own set of complications such as alterations in gut transit time and composition of gut eco-culture. The primary aim of this study was to investigate the effect of microbial cell preparation on the return of gut function, white blood cell count, C-reactive protein levels, number of days on mechanical ventilation, and length of stay in ICU. A consecutive cohort of 60 patients admitted to the ICU in University Malaya Medical Centre requiring enteral feeding were prospectively randomized to receive either treatment (n = 30) or placebo (n = 30). Patients receiving enteral feeding supplemented with a course of treatment achieved a faster return of gut function and required shorter duration of mechanical ventilation and shorter length of stay in the ICU. However, inflammatory markers did not show any significant change in the pretreatment and posttreatment groups. Overall, it can be concluded that microbial cell preparation enhances gut function and the overall clinical outcome of critically ill patients receiving enteral feeding in the ICU.

Definition, prevalence, and outcome of feeding intolerance in intensive care: a systematic review and meta-analysis

Clinicians and researchers frequently use the phrase 'feeding intolerance' (FI) as a descriptive term in enterally fed critically ill patients. We aimed to: (1) determine what is the most accepted definition of FI; (2) estimate the prevalence of FI; and (3) evaluate whether FI is associated with important outcomes. Systematic searches of peer-reviewed publications using PubMed, MEDLINE, and Web of Science were performed with studies reporting FI extracted. We identified 72 studies defining FI. In 33 studies, the definition was based on large gastric residual volumes (GRVs) together with other gastrointestinal symptoms, while 30 studies relied solely on large GRVs, six studies used inadequate delivery of enteral nutrition (EN) as a threshold, and three studies gastrointestinal symptoms without reference to GRV. The median volume used to define a 'large' GRV was 250 ml (ranges from 75 to 500 ml). The pooled proportion (n = 31 studies) of FI was 38.3% (95% CI 30.7-46.2). Five studies reported outcomes, all of them observed adverse outcome in FI patients. In three studies, respectively, FI was associated with increased mortality and ICU length-of-stay. In summary, FI is inconsistently defined but appears to occur frequently. There are preliminary data indicating that FI is associated with adverse outcomes. A standard definition of FI is required to determine the accuracy of these preliminary data.

Parenteral nutrition increases susceptibility of ileum to invasion by E coli

BACKGROUND

Parenteral nutrition (PN), with the lack of enteral feeding, compromises mucosal immune function and increases the risk of infections. We developed an ex vivo intestinal segment culture (EVISC) model to study the ex vivo effects of PN on susceptibility of the ileum to invasion by extra-intestinal pathogenic Escherichia coli (ExPEC) and on ileal secretion of antimicrobial secretory phospholipase A2 (sPLA2) in response to the pathogen.

MATERIALS AND METHODS

Study 1: Using mouse (n = 7) ileal tissue, we examined the effects of ileal region (proximal versus distal) and varying ExPEC inoculum concentrations on ex vivo susceptibility to ExPEC invasion and sPLA2 secretion. Study 2: Ten mice were randomized to oral chow or intravenous PN feeding for 5 d (n = 5/group). Using the EVISC model, we compared the susceptibility of ileal tissue to invasion by ExPEC and sPLA2 secretion in response to the pathogen.

RESULTS

Study 1: The proximal ileum was more susceptible to invasion (P < 0.0001) and secreted lower amounts of sPLA2 (P = 0.0002) than the distal ileum. Study 2: Ileal tissue from PN-fed animals was more susceptible (approximately 4-fold, P = 0.018) to invasion than those from chow-fed animals. Ileal tissue from PN-fed animals secreted less sPLA2 (P < 0.02) than those from chow-fed animals.

CONCLUSIONS

The data illustrate EVISC as a reproducible model for studying host-pathogen interactions and the effects of diet on susceptibility to infections. Specifically, the findings support our hypothesis that PN with the lack of enteral feeding decreases mucosal responsiveness to pathogen exposure and provides a plausible mechanism by which PN is associated with increased risk of infectious complication.

Probiotics in the critically ill: a systematic review of the randomized trial evidence

OBJECTIVE

Critical illness results in changes to the microbiology of the gastrointestinal tract, leading to a loss of commensal flora and an overgrowth of potentially pathogenic bacteria. Administering certain strains of live bacteria (probiotics) to critically ill patients may restore balance to the microbiota and have positive effects on immune function and gastrointestinal structure and function. The purpose of this systematic review was to evaluate the effect of probiotics in critically ill patients on clinical outcomes.

DESIGN

Systematic review.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We searched computerized databases, reference lists of pertinent articles, and personal files from 1980 to 2011. We included randomized controlled trials enrolling critically ill adults, which evaluated probiotics compared to a placebo and reported clinically important outcomes (infections, mortality, and length of stay). A total of 23 randomized controlled trials met inclusion criteria. Probiotics were associated with reduced infectious complications as documented in 11 trials (risk ratio 0.82; 95% confidence interval 0.69-0.99; p = .03; test for heterogeneity p = .05; I 44%). When data from the seven trials reporting ventilator-associated pneumonia were pooled, ventilator-associated pneumonia rates were also significantly reduced with probiotics (risk ratio 0.75; 95% confidence interval 0.59-0.97; p = .03; test for heterogeneity p = .16; I 35%). Probiotics were associated with a trend toward reduced intensive care unit mortality (risk ratio 0.80; 95% confidence interval 0.59-1.09; p = .16; test for heterogeneity p = .89; I 0%) but did not influence hospital mortality. Probiotics had no effect on intensive care unit or hospital length of stay. Compared to trials of higher methodological quality, greater treatment effects were observed in trials of a lower methodological quality.

CONCLUSIONS

Probiotics appear to reduce infectious complications including ventilator-associated pneumonia and may influence intensive care unit mortality. However, clinical and statistical heterogeneity and imprecise estimates preclude strong clinical recommendations. Further research on probiotics in the critically ill is warranted.

Probiotic treatment with Probioflora in patients with predicted severe acute pancreatitis without organ failure

BACKGROUND

We previously demonstrated that probiotic prophylaxis, in patients with predicted severe pancreatitis, did not prevent infectious complications but unexpectedly increased the risk of bowel ischemia and mortality. The suggestion that these negative findings are only observed in the presence of organ failure at the start of probiotic treatment has not been confirmed.

METHODS

In a retrospective analysis, all patients with predicted severe acute pancreatitis without initial organ failure admitted to a medium care facility of a teaching hospital in Prague from January 2003 to December 2010 were included. All patients routinely received probiotic treatment with Probioflora. Total parenteral nutrition (TPN) was routinely started and shifted toward total enteral nutrition. Infectious complications, mortality and the incidence of bowel ischemia were recorded.

RESULTS

99 consecutive patients, mean age 56 years, were included. Infectious complications occurred in 42 patients (42%), consisting of bacteremia (n = 40), pneumonia (n = 11) and infected necrosis (n = 11). Bowel ischemia was detected in two patients (2%). Overall mortality was 8%.

CONCLUSION

In this retrospective study no apparent positive or negative impact of probiotic treatment with Probioflora was demonstrated when administered to patients with predicted severe acute pancreatitis without initial organ failure.

Gut-origin sepsis: evolution of a concept

The concept of bacterial translocation and gut-origin sepsis as a cause of systemic infectious complications and the multiple organ dysfunction syndrome (MODS) in surgical and ICU patients has emerged over the last several decades, although the exact clinical relevance of these phenomena continues to be debated. Thus, the goal of this review is to trace the evolution of gut-origin sepsis and gut-induced MODS and put these disorders and observations into clinical perspective. Additionally, the mechanisms leading to gut-derived complications are explored as well as therapeutic options to limit or prevent these complications. From this work, several major conclusions emerge. First, that bacterial translocation occurs clinically and is responsible for increased infectious complications in patients undergoing major abdominal surgery. However, the phenomenon of bacterial translocation is not sufficient to explain the development of MODS in ICU patients. Instead, the development of MODS in these high-risk patients is likely due to gut injury and the systemic spread of non-microbial, tissue-injurious factors that reach the systemic circulation via the intestinal lymphatics. These observations have resulted in the gut-lymph hypothesis of MODS.

Acute intestinal failure in surgical patients: an audit of incidence, management and outcomes in an irish hospital, and compliance with ASGBI guidelines

BACKGROUND

Acute intestinal failure (AIF) is defined as an inability to tolerate 80% of nutritional requirements delivered enterally for a minimum of 48 h. In surgical patients it commonly relates to abdominal sepsis, intestinal obstruction, or ileus. The prevalence of AIF in surgical units in Ireland has not previously been studied.

METHODS

We retrospectively audited the general surgical and ICU departments in St James's Hospital over a 3-month period to identify patients with AIF and followed their management and outcomes focusing on the need for artificial nutrition and surgical intervention.

RESULTS

Fifty-four surgical patients (11.4% of surgical emergency admissions) were diagnosed with AIF over the 3-month period. Of these, 30 (55.6%) required nutritional support; 26 (48.2%) had surgical ± radiological intervention and 6 (11.1%) had radiological intervention alone. Abdominal sepsis was present in 17 (31.5%) patients, a group that required significantly longer parenteral (14.6 vs. 6.7 days, p 0.029) and enteral (13.9 vs. 2.2 days, p 0.005) nutrition than AIF patients without abdominal sepsis. AIF also took longer to resolve in (5.8 vs. 4.2 days, p 0.024) in sepsis versus nonsepsis patients. The majority of patients (n = 43, 80%) were referred to clinical nutrition teams early after having symptoms for 3.77 days (range 1-21) and 72% had complete nutritional assessment clearly documented.

CONCLUSION

AIF is common, and can often be treated conservatively. Early linkage with nutrition services is recommended. Early diagnosis of abdominal sepsis is important as this cohort of patients can be particularly difficult to manage.