Perioperative oral nutrition

The impact and safety of preoperative oral or intravenous carbohydrate administration versus fasting in colorectal surgery--a randomized controlled trial

BACKGROUND AND AIMS

Increasing evidence suggests that preoperative fasting, as was the clinical practice for many decades, might be associated with untoward consequences and that a standardized preoperative intake of nutrients might be advantageous; this is a component of the enhanced recovery after surgery (ERAS) concept. Thus, in a randomized controlled trial we compared preoperative fasting with preoperative preparation with either oral or intravenous intake of carbohydrates, minerals and water. Biochemical, psychosomatic, echocardiographic and muscle-power parameters were assessed in surgical patients with colorectal diseases during the short-term perioperative period. We also assessed the safety of peroral intake shortly before surgery.

METHODS

A total of 221 elective colorectal surgery patients in this bicentric, randomized, prospective and blinded clinical trial were divided into three groups: A - patients fasting from midnight (control group); B - patients supported preoperatively by glucose, magnesium and potassium administered intravenously; C - patients supported preoperatively by oral consumption of a specifically composed solution (potion).

RESULTS

The general perioperative clinical status of patients in groups C and B was significantly better than those in group A. Psychosomatic conditions postoperatively were found to be best in group C (P < 0.029). The rise in the index of insulin resistance (QUICKI) from the preoperative to the postoperative state was significant in group A (P < 0.05). The systolic and diastolic function of the left ventricle improved postoperatively in group C vs. group A (P < 0.04), and the ejection fraction was also significantly higher postoperatively in group C vs. group A (P < 0.03). The gastric residual volume was 5 ml and the pH of stomach juice was 3.5-5 in all groups without statistically significant difference. No difference was found in the length of hospital stay or the rate of complications.

CONCLUSIONS

Preoperative fasting does not confer any benefit or advantage for surgical patients. In contrast, consumption of an appropriate potion composed of water, minerals and carbohydrates offers some protection against surgical trauma in terms of metabolic status, cardiac function and psychosomatic status. Peroral intake shortly before surgery did not increase gastric residual volume and was not associated with any risk.

Effects of preoperative flavonoid supplementation on different organ functions in rats

BACKGROUND

Previously it has been reported that preoperative feeding preserves heart function in rats after intestinal ischemia-reperfusion. To further improve postoperative organ function, bioactive nutrition compounds were selected in vitro against the xanthine oxidase radical cascade, an enzyme suggested to play a key role in the induction of single- or multiple-organ dysfunction.

METHODS

Flavonoids were selected in vitro for their capacity to (1) inhibit xanthine oxidase, (2) scavenge superoxide, and (3) scavenge peroxylradicals. The most bioactive flavonoids were added to the preoperative nutrition to study their effect on postintestinal ischemia-reperfusion organ function.

RESULTS

A combination of flavonoids selected on basis of effective flavonoid xanthine oxidase inhibition and superoxide scavenging resulted in increased superoxide scavenging. In vivo, the selected flavonoid mixture significantly lowered postischemic intestinal apoptosis and intestinal oxidative stress indicated by malondialdehyde concentration when compared with ischemia-reperfusion fasted and sham-fasted animals. Moreover, this flavonoid mixture significantly lowered plasma creatinine and urea concentration, both indicating a better postoperative kidney function. Furthermore, oxidative stress measured as this flavonoid mixture when compared with control significantly lowered plasma malondialdehyde concentration in fed rats.

CONCLUSIONS

Coadministration of bioactive flavonoid mixture to preoperative nutrition, in contrast to fasting, attenuates ischemia-reperfusion injury by preserving kidney function in the rat and decreasing apoptosis in the intestine.

Preoperative feeding preserves heart function and decreases oxidative injury in rats

OBJECTIVE

The nutritional status of a patient has been implicated as an important factor in the development of postoperative complications. Fasting before an operation may have detrimental effects on the metabolic state. We hypothesized that there was a positive correlation between preoperative nutritional status and postoperative organ function.

METHODS

Preoperative feeding was compared with fasting with respect to effects on organ function and biochemical parameters in an animal model of extensive large abdominal surgery. Male Wistar rats were fed ad libitum or fasted for 16 h, after which the arteria mesenterica superior was clamped for 60 min followed by 180 min of reperfusion.

RESULTS

After the ischemic period, heart function was significantly better in animals that were fed ad libitum than in fasted animals. Moreover, after intestinal ischemia and reperfusion, fed rats showed significantly higher levels of intestinal adenosine triphosphate and a significantly higher malondialdehyde concentration in the intestine and lung than did fasted rats. The ratio of adenosine triphosphate to adenosine diphosphate in the liver, an indicator of energy status, in fed rats was similar to that in a sham group, whereas fasted animals showed a significantly lower value.

CONCLUSIONS

Preoperative nutrition in contrast to fasting may attenuate ischemia/reperfusion-induced injury and preserve organ function in the rat.

Prevention of liquid-diet-induced damages on submandibular glands by selenium supplementation in rats

This study was designed to explore the protective effects of selenium on submandibular glands of rats that were maintained on liquid diet. The animals kept on liquid diet for 10 days following 20 days of solid diet, had severe degeneration on both acinar and ductal cells: pycnotic nuclei, enlarged granular endoplasmic reticulum, swollen mitochondria with separated cristae, reduction of secretory granules and abundant lipid droplets were observed. Body and gland weights of these animals were found to decrease significantly compared to those of control group given solid diet for 30 days. The animals that were fed 20 days with solid diet + 10 days liquid diet and also given selenium 0.4 mg/kg for 30 days, did not have any remarkable sign of degeneration on submandibular glands, and their gland weights significantly increased when compared to the animals fed with liquid diet without selenium supplementation. Submandibular glands of the group that was maintained on solid diet for 30 days and supplemented with selenium in drinking water were found to be normal. They showed consistent gain in both body and gland weights almost equal to that of control group. As a result, we assume that adding selenium in liquid diet can prevent the detrimental effects of liquid diet consumption on submandibular glands.

Nutritional support in the postoperative period

Nutritional support is used frequently as a treatment modality in the postoperative patient. Indications for nutrition support, patient selection, mode of administration, contents of solutions and complications of therapy are issues that the consulting internist must address. The role of a nutrition support team and optimal communication between the consultant and members of the surgical staff are emphasized.

Screening swallowing function of patients with acute stroke. Part two: Detailed evaluation of the tool used by nurses

Stroke is a common problem and a major consumer of health and social care budgets in the UK. Dysphagia is a frequent accompaniment and its management has the potential to exert significant influence within the rehabilitation process. This study explores in detail the performance of a screening tool (based on the Standardized Swallowing Assessment) used by nurses. Based on 68 complete screening episodes by independently competent nurses, with the effects of chance removed, the tool demonstrated good agreement with summative clinical judgement of swallow function (kappa = 0.88). The accuracy of results supported the full training and education programme for nurses. Not all components of the tool were required; analyses suggested elimination of three variables but further exploration is warranted. As a component of evidence-based guidelines for nutritional support in acute stroke, the screening initiative contributed to improved patient outcomes.