gastrointestinal motility disorders in critically ill patients

Gastrointestinal motility disorders in Critically ill patients

Ubaidur Rahaman

Senior Resident, Critical Care Medicine,

SGPGIMS, Lucknow,

India

Advantage of enteral nutrition in critically ill

metabolic, immunologic and mucosal barrier protection against bacterial translocation

Early enteral nutrition within 24 hours of admission is recommended

Post injury hypermetabolic response and magnitude of translocation: prevention by early enteralnutrition. Gianotti L, Nelson JL, Alexander JW, et al. Nutrition. 1994;10:225-231

ESPEN guidelines on enteral nutrition: intensive care. Kreymann KG, Berger MM, Deutz NE, et al. Clin Nutr. 2006;25:210-223.

EPIDEMIOLOGY

Intolerance to feed: 60%

Delayed gastric emptying: 50-80%

Enteral tube feeding in the intensive care unit: factors impeding adequate delivery. McClave SA, Sexton LK, Spain DA, et al. Crit Care Med. 1999;27:1252-1256.

Upper digestive intolerance during enteral nutrition in critically ill patients: frequency, risk factors, and complications. Mentec H, Dupont H, Bocchetti M, et al. Crit Care Med. 2001;29:1955-1961

IMPACT ON PATIENT CARE

HAP bacterial translocation leading to sepsis and multi-organ failure

Nutritional deficiencyAbsorption of enterally given drugs

Increased hospital stay and mortality

Increased complication

GI MOTILITY- PHYSIOLOGY

reflex wave of contraction in oro-caudal direction in response to

stretching of wall by luminal content

spontaneous rhythmic fluctuation in membrane potential. Initiated by stellate muscle like pacemaker cells.

function is to co ordinate peristaltic activity.

during fasting, cycles of motor activity migrate from stomach to distal ileum. Immediately stopped on ingestion of food.

Each MMC consists of Phase I- quiescent periodPhase II- irregular contraction

Phase III- burst of regular contractionFunctionunsettled

Probably clears stomach and small intestine of luminal contents in preparation for next meal.

Peristalsis

Basal electrical activity (BEA)

Migrating motor complex

GI MOTILITY- PHYSIOLOGYGASTRIC EMPTYING

FACTORS AFFECTING GASTRIC EMPTYING

Increasing age and female gender- delayed gastric emptying

Volume- more volume – more rapid emptying•caloric density/ unit volume - high caloric density – slow gastric emptying

•Tightly controlled Nutrient delivery- 200 Kcal/ h ( 2-3 Kcal/min) into duodenum•osmolality- high osmolalty- slow gastric emptying

• nutrient content- carb> protien>fat

Intragastric pH- omeprazole delays gastric emptyingTemperature- low tempreature- delays gastric emptying

Physio. Res. 2003;1-30Neurohumoral control of gastrointstinal motility.

MB Hansen

FOOD

CONTROL AND REGULATION OF GI MOTILITY

Cholecystokinin (CCK), peptide tyrosine tyrosine (P YY), motilin, glucagon like peptide (GPP 1)fundal relaxation and inhibit gastric emptying

Dopaminedecreases gastric emptying and intestinal peristalsis

Motilinamplifies and induces MMC activity

Opioids and serotonin ( 5HT)

ENS--↔-ANS--↔-CNS

Hormonal factors

Neural factors

•absent phase III MMC activity

•delayed fundal relaxation, prolonged recovery

•Reduced antral motility

•increased isolated pyloric activity

Diminished functional association between

proximal and distal gastric motility

•Gastroparesis

GI MOTILITY DYSFUNCTION IN CRITICALLY ILLPATHOPHYSIOLOGY

stomach

Altered GI Motility in Critically Ill Patients: Current Understanding of Pathophysiology, Clinical Impact, and Diagnostic Approach

Andrew Ukleja, MD. Nutr Clin Pract. 2010;25:16-25


World J Gastroenterol 2006 July 21; 12(27): 4383-4388Proximal gastric response to small intestinal nutrients is abnormal

in mechanically ventilated critically ill patientsNguyen N, Fraser R, Chapman M, Bryant R, Holloway R, Vozzo R, Feinle-Bisset

•proximal gastric relaxation is delayed

•fundic wave activity is reduced

•the recovery of proximal gastric volumes to pre-stimulation levels is delayed.


Gut 2005;54:1384-1590Antro-pyloro-duodenal response to gastric and duodenal nutrient in the critically ill patients.

Chapman M, Fraser R, Vozzo R, Bryant L, Tam W, Nguyen N, Zacharakis B, Butler R, Davidson G, Horowitz M.

A five minute recording of pressure waves during small intestinal infusion of nutrient

Absence of antral activity andfrequent isolated pyloric pressure waves


Abnormal antro-pyloro-duodenal response

Crit Care Med 2007; 35: 82-88intolerance in critical illness is associated with increased basal and nutrient-stimulated

plasma cholecystokinin concentrations. Nguyen N, Fraser R, Chapman M, Bryant L, Holloway R, Vozzo R, Wishart J, Feinle-Bisset C, Horowitz M.


P <0.01

Plasma CCK concentration during fasting and duodenal stimulation

Intensive Care Med 2008; 34:1246–1255Diminished functional association between proximal and distal gastric motility

in critically ill patients. Nguyen NQ, Fraser RJ, Bryant LK, et al.


Fundic waves(FW) and propagated antral waves(PAW)during fasting and duodenal nutrient stimulationChanges in gastric volume during nutrient infusion

In critical illness association between proximal and distal gastric motility is abnormal

continues

Outline of study technique and position of recording assemblies

Intensive Care Med 2008; 34:1246–1255Diminished functional association between proximal and distal gastric motility in critically ill patients. Nguyen NQ, Fraser RJ, Bryant LK, et al.

Trans-mural potential

difference


•Reduced flushing of nutrient content•MMC disorganization:

phase I- increased, phase II- decreased, phase III- retrograde

•Pseudo-obstruction (Ogilivie syndrome)

•Increased retrograde MMC III activity•Persistence of MMC phase III during feeding

•MMC activity starting in duodenum instead of antrum•ileus

Current Opinion in Clinical Nutrition and Metabolic Care 2009, 12:161–167Motility disorders in the ICU: recent therapeutic options and clinical practice

Kerstin D. Rohm, Joachim Boldt, Swen N. Piper.

Small intestine

Colon

GI MOTILITY DYSFUNCTION IN CRITICALLY ILLETIOLOGY AND RISK FACTORS

SurgeryAbdominal, head or spinal

Drugs

Glucose or fluid imbalance

Acid- base or electrolyte imbalance

Hypoxaemia

Hypoperfusion- systemic or regional

SIRS/ Sepsis


SURGERY

Cannon WB, Murphy FT:The movement of the stomach and intestine in some surgical conditions.

Ann Surg 1906, 43:512–536.

mechanism

NEURONALLocal manipulation

↑NO from inhibitory motor neurons↑VIP

HUMORALMacropahage/ monocytes

↑NO, PGs

•Anesthetics- halothane

• sedatives- midazolam, propofol

• analgesics- opioids, ketamine

•Catecholamines

• alpha agonists- clonidine, dexmedetomidine

•Calcium channel blockers

•Proton pump inhibitors


Drugs

Opioids

Fundal relaxationReduced antral contraction

Reduced MMC phase III

Ketamine seems to have no advantage over fentanylSchmittner, Vajkoczy, Horn. Effects of fentanyl and S(+) ketamine on cerebral hemodynamics, gastrointestinal motility and

need for vasopressors in patients with intracranial pathology: apilot study. J neurosurg Anesthesiol

Propofol showed beneficial gut effects over midazolam.Nguyen NQ, Chapman MJ, Fraser RJ, et al. The effects of sedation on gastricemptying and

intra-gastric meal distribution in critical illness. Intensive Care Med 2008; 34:454–460


Hyperglycemia:Gastric feeding was equally successful in diabetics as in non diabetics

Nguyen NZ et al. Gastric feed intolerance is not increased in critically ill patients with type II diabetes. Inten Car Med 2007;33:1740-1745

Normoglycemia attained by intensive insulin therapy seems to minimize feed intolerance in critical illness.

Nguyen et al. the relationship between blood glucose control and intolerance to enteral feeding during critical illness. Inten Car Med 2007;33:2085-2092

Vasopressorsdecreased antral contractions and orocaecal transit and longer ICU length of stay

Dive A, Foret F, Jamart J, et al. Effect of dopamine on gastrointestinal motility during critical illness. Intensive Care Med 2000; 26:901–907.


Liberal fluid balance prolongs the duration of motility disturbancesand is associated with longer latency to first gastric emptying and first passage of flatus and stool as well as to

hospital discharge.

GI MOTILITY DYSFUNCTION IN CRITICALLY ILL ETIOLOGY AND RISK FACTORS

Dehydration and or hypovolemia may be associated with post operative GI dysfunctionand that increased perioperative fluid administration has been associated with

improved indices of gut perfusion and reduced PGID

Fluid balance

Effect of salt and water balance on recovery of gastrointestinal function after elective colonic resection: a randomised controlled trial.

Lobo DN, Bostock KA, Neal KR,Perkins AC, Rowlands BJ, Allison SP. Lancet 2002;359:1812–1818

Effect of intraoperative fluid management on outcome after intraabdominalsurgery.Nisanevich V, Felsenstein I, Almogy G, Weissman C, Einav S, Matot I. Anesthesiology 2005; 103:25–32

Goal-directed intraoperativefluid administration reduces length of hospital stay after major surgery

Gan TJ, Soppitt A, Maroof M, et al. Anesthesiology 2002;97:820–6.

Perioperative plasma volume expansion reduces the incidence of gut mucosal hypoperfusion during cardiac surgery

Mythen MG, Webb AR. Arch Surg 1995;130:423–9.

•Diabetes, thyroid disorders•neurological disorders,

•Collagen vascular disorders•Functional GI motility disorders

Alcoholnicotine

Regular use of laxative


Co morbidity

Substance abuse

ASSESSMENT OF GI DYSMOTILITY

GastroparesisGastric residual volume (GRV)

IleusBowel sounds

defecation

tolerance of EN•pain and/ or distention,

•physical exam- distended, tense abdomen, raised IAP• passage of flatus and stool,

•abdominal radiographs

Physiological stool frequency1-2 evacuations/ day to 1 evacuation Q3-4 day

evidence of bowel motility is not required to initiate enteral feeding

ASSESSMENT OF GI DYSMOTILITY

weak relationship with gastric emptying

Depends on position of tube, tube collapsibility, tube size, volume of syringe used

Operator performing the test

25% patients with GRV >150ml have normal gastric emptying and do not require prokinetic

In patients with normal gastric emptyingGRV- 232-464 ml during enteral feeding @ 25-125ml/hr

two large studies in critically ill patientsmost GRVs <150 ml

Crit Care Clin 26 (2010) 481–490Gastric Residual Volumes in Critical Illness: What Do They Really Mean?

Ryan T. Hurt, Stephen A. McClave.

GRV

MANAGEMENT

• in critically ill patients mechanism underlying dysmotility are usually complex

•Relative contribution of control systems to regulation of GI motility varies along the alimentary canal and disease nature and course

•Propulsive motility occurs only when there is co-coordinated pattern of contraction and relaxation along the length of gut

It is unrealisticone single drug alone is able to promote propulsive motility over entire GI tract

DRUGS

PROKINETIC

metocloperamide, Domperidone, Cisapride, Itopride

OPIOID ANTAGONIST

Naloxone, Alvimopan, methylnaltrexone

MOTILIN AGONIST

Erythromycin

AChE INHIBITOR

Neostigmine

5HT4 AGONIST

tegaserod

PROKINETIC DRUGS

•IV administration is more potent than oral•Effect to facilitate gastric emptying and improving tolerance to enteral feeding has been

confirmed in 2 RCTs•Effect on colonic transit time is controversial

•Lack beneficial effect in post op ileus

Microbial resistanceno evidence that short term, low dose regimen of erythromycin increases resistance

QT prolongationrisk increases above plasma level approx 30 mg/ml.

this is above level which can be achieved by 100 mg ivi dose.Caution

has to be taken in cardiomypathy, CHF, CAD, AFib, bradycardia, hypokalemia, hypomagnesemia

ERYTHROMYCIN

•Effect limited to upper GI tract, no effect on large bowel

•Beneficial effect on GI transit and enteral feed tolerance when give IV, ineffective when given TNG

•Duration of post op ileus remains unaltered.

•Effect remains controversial

•Found to be ineffective in post op ileus at dose 0.5 mg IMI Q3H total 3 doses.

•Prompt colonic decompression following orthopedics surgery at dose 2 mg IVI.

•Acute colonic pseudo obstruction- 2-2.5 mg ivi over 3-3- min caused resolution with a success rate of 80-90%.

PROKINETIC DRUGS

METOCLOPERAMIDE

NEOSTIGMINE

may be beneficial in GI motor disturbances that are unrelated to opiate use

NALOXONE

•Release of ACh by metocloperamide+ inhibition of breakdown by neostigmine•Dose should be kept in indicated range and duration of infusion limited to 2 hours.

Adverse effects•Symptomatic bradycardia

•Increased tracheo-bronchial secretions and salivation•Tracheal suction should be avoided- additional vagal stimulation

Contra indication•Mechanical bowel obstruction, gastrointestinal ischemia or perforation,

•pregnancy, uncontrolled arrhythmias, severe bronchospasm

PROKINETIC DRUGS

Combination of metocloperamide and neostigmine

• Erythromycin is more effective than metoclopramide in treating feed intolerance• But rapid decline in effectiveness renders both treatments suboptimal.

•Rescue combination therapy is highly effectivefurther study is required to examine its role as the first-line therapy

Kaplan Meier plots comparing the effects

Crit Care Med. 2007 Feb;35(2):483-9.

Erythromycin is more effective than metoclopramide in the treatment of feed intolerance in critical illness.

Nguyen NQ, Chapman MJ, Fraser RJ, Bryant LK, Holloway RH.

ALGORYTHM FOR TREATMENT OF GI DYSMOTILITY

Early use of supportive therapeutic options

Stimulant and osmotic laxative

Reduced use of drugs with inhibitory effect onGI motility

Goal directed specific therapy-PROKINETICS

Opioid receptor antagonist

gastroparesis

gastroparesis and Intestinal motor inhibition

intestinal motor inhibition without gastroparesis

Clin Nutr 2008; 27:25–41Standardized concept for the treatment of gastrointestinaldysmotility in critically ill patients:current

status and future options. Herbert MK, Holzer P..

ALGORYTHM FOR TREATMENT OF GI DYSMOTILITY

10-30 mg ivi +0.5-1.5 mg ivi Q24H

(in 250 ml NS over 1-2 hours

Metocloperamide +Neostigmine

40 mg ivi Q24H( in 100 ml NS over 30-60 min)

Ceruletide1st line

Impaired intestinal motility without gastroparesis

10-30 mg ivi +0.5-1.5 mg ivi Q24H

(in 250 ml NS over 1-2 hours)

Metocloperamide + neostigmine

After 24 hours

100 mg ivi Q8H for 3 daysErythromycin1st line

Gastroparesis and impaired intestinal motility

30-40 mg PODomperidone3rd line

10 mg iviMetocloperamide2nd line

100 mg ivi Q8H for 3 daysErythromycine1st line

Impaired gastric emptying

3-12 mg PO Q8hNaloxone

Opioid receptor antagonist

Clin Nutr 2008; 27:25–41Standardized concept for the treatment of gastrointestinaldysmotility in critically ill patients:

current status and future options. Herbert MK, Holzer P

SPECIAL CONSIDERATION FOR USE OF PROKINETICS

Reduce doseOpioids, sedatives, alpha agonist and catecholamines

as soon and as much possible

Only one stimulation per day

Dose should not be increased Tachyphylaxis, increased stimulation- tetany

If no benefit over use of several consecutive daysHoliday of 1 day

Clin Nutr 2008; 27:25–41Standardized concept for the treatment of gastrointestinaldysmotility in critically ill patients:

current status and future options. Herbert MK, Holzer P

Check GRV Q4h

GRV>400 ml

nContinue EN at the current ratenright lateral decubitus position for 30 minutes

nMetocloperamide 10 mg, ivi Q6h; naloxone 8 mg in 10 ml saline TNG Q6h

>400 ml- hold NG feed

GRV<500 ml- return feed to patient

Recheck GRV in 4 hours

Recheck GRV every 2 hours

GRV < 400 ml- restart NG feeding

intolerance consider reducing rate by 25 mL/h

or to baseline of 25 mL/h

Tolerance restart at same rate

recommendations for using GRV in an enteral nutrition protocol

Crit Care Clin 26 (2010) 481–490Gastric Residual Volumes in Critical Illness: What Do They Really Mean?

Ryan T. Hurt, Stephen A. McClave.

FUTURE PHARMACOLOGICAL OPTIONS

TZP-101

Gherlin receptor agonist

Mitemcinal

Alemicinal,

Motilin agonist

Dexloxiglumide

Cerulein

CCK receptor antagonist

Renazapride

Levosulpiride

5 HT receptor agonist

PROKINETICS WITHDRAWN FROM MARKET

Itopridelack of efficacy,

further development stopped in 2006 by Axcan PharmaAvailable in Japan, few European countries, India

Tegaserodischemic colitis, cardio toxicity,

withdrawn in US in 2007,available in some European countries

ACUTE COLONIC PSEUDO OBSTRUCTIONOGILIVIE SYNDROME

Ogilvie H.Large-intestine colic due to sympathetic deprivation; a new clinical syndrome.

Br Med J 1948; 2:671–673.

Massive dilatation of colon with obstructive symptoms, in the absence of mechanical obstruction

Risk of ischemia and perforation 3-15% leading to mortality of 50%

Advanced age, large ceacal diameter (>10 cm), and duration of distension

•bowel rest, fluid and electrolyte optimization•Rectal tube may be effective

•Stop drugs delaying motility- opioids, anticholinergics, CCB•Laxatives particularly osmotic are contra indicated

Supportive measures

…continued

3 double blind RCT have documented effectiveness

•Neostigmine for the treatment of the acute colonic pseudo-obstruction.Ponec RJ, Saunders MD, Kimmey MB. N Engl J Med 1999; 341: 137–141

•Neostigmine infusion: new standard ofcare for acute colonic pseudo-obstruction?Amaro R, Rogers AI. Am J Gastroenterol 2000; 95: 304–305.

•Neostigmine resolves critical illness-related colonic ileus in intensive care patients with multiple organ failure: a prospective, double-blind, placebo-controlled trial.

van der Spoel JI, Oudemans-van Straaten HM, Stoutenbeek CP, Bosman RJ, Zandstra DF. Intensive Care Med 2001; 27: 822–827.

•Watch for secretions, bradycardia, hypotension, bronchospasm•Risk can be reduced by iv infusion compared to bolus

Neostigmine

The benefit derived from one or two doses of neostigmine largely outweigh the risk of administration

Relative contra indication•Recent history or signs of perforation or peptic ulcer

•Myocardial infarction, use of beta blockers•Obstructive airway disease

•S.creatinine>3 mg/dl


…continued

Effect of polyethylene glycol electrolyte balanced solution on patients with acute colonic pseudo-obstruction after resolution of colonic dilatation: a prospective, randomized, placebo controlled trial.

Sgouros SN, Vlachogiannakos J, Vassiliadis K, Bergele C, Stefanidis G, Nastos H et al. Gut 2006; 55: 638–642

•significant reduction in recurrent caecal dilatation,• increased in stool and flatus evacuation, •decrease in caecal and colonic diameter

•reduction in abdominal circumference.

(after initial resolution using neostigmine or decompression)

Polyethylene glycol (PEG)

•Efficacy has not been assessed in RCT•Reported to be successful in 80%,

•Laborious and hazardous•High suspicion of ischemia- should be carried out in OT

Endoscopic decompression

mortality 30-60%

Surgery


EFFECT OF ENTERLA NUTRITION ON GUT MOTILITY

Clin Nutr 2008; 27:25–41

Standardized concept for the treatment of gastrointestinaldysmotility in critically ill patients:current status and future options.

Herbert MK, Holzer P

No evidence that impaired intestinal motility in critically illimproves from enteral nutrition,

either standard formulae or immune modulating formulae orenriched with antioxidant or fiber

NON PROKINETIC THERAPY

Post pyloric feedingFailure of NG feeding and no improvement with prokinetics

Epidural anesthesia in post op period

Systemic lidocaine administration during induction and peri/post operative period

Computerized bibliographic search of published research (1980-2001)

Crit Care Med. 2002 Jul;30(7):1429-35.

Gastrointestinal promotility drugs in the critical care setting: a systematic reviewof the evidence

Booth CM, Heyland DK, Paterson WG

18 studies•6 studies of feeding tube placement,

•11 studies evaluating gastrointestinal function•1 study of clinical outcomes

•As a class of drugs, promotility agents appear to have a beneficial effect on GI motility in critically ill patients.

•A one-time dose of erythromycin may facilitate small-bowel feeding tube insertion.

•metoclopramide appears to increase physiologic indexes of gastrointestinal transit and feeding tolerance.

•Concerns about safety and lack of effect on clinically important outcomes preclude strong treatment recommendations

REVIEW OF LITERATURE

Prospective, randomized, controlled trial.

Crit Care Med. 2000 May;28(5):1408-11.Metoclopramide for preventing pneumonia in critically ill patients receiving enteral tube feeding:

a randomized controlled trial.Yavagal DR, Karnad DR, Oak JL

total of 305 consecutive patients requiring placement of a nasogastric tube for >24 hrs.

•Metoclopramide delayed the development of nosocomial pneumonia, •But it did not decrease its frequency rate

•No effect on the mortality rate in critically ill patients receiving NG feeding.



Crit Care Med 2007; 35(11).

Prokinetic therapy for feed intolerance in critical illness: one drug or two?Nguyen N, Chapman, M, Fraser, R, Bryant, L, Holloway, RH

Seventy-five mechanically ventilated, medical patients with feed intolerance (GRV >250 mL).

• combination therapy- erythromycin 200mg ivi Q12H + metoclopramide 10mg ivi Q6H (n 37)OR erythromycin alone (n 38)

•Gastric feeding was re-commenced•6-hourly NG aspirates performed. Duration of study- 7 days

••Successful feeding - GRV<250 mL with the feeding rate >40 mL/hr


…continued

•combination therapy with erythromycin and metoclopramide is more effective•should be considered as the first-line treatment.

•Tachyphylaxis was less with combination therapy.•no difference in the length of hospital stay or mortality rate

•Watery diarrhea was more common with combination therapy but was not associated with enteric infections,

including Clostridium difficile.

P <0.01 vs erythromycin

Crit Care Med 2007; 35(11).

Prokinetic therapy for feed intolerance in critical illness: one drug or two?Nguyen N, Chapman, M, Fraser, R, Bryant, L, Holloway, RH


Crit Care Med. 2007 Feb;35(2):483-9.

Erythromycin is more effective than metoclopramide in the treatment of feed intolerance in critical illness.

Nguyen NQ, Chapman MJ, Fraser RJ, Bryant LK, Holloway RH.

90 mechanically ventilated, medical patients with feed-intolerance (GRV ≥250 ml).

• Given either metoclopramide 10 mg ivi Q6H (n=45) or erythromycin 200 mg ivi Q12H (n=45).

• After the first dose, NG feeding commenced •Q6H NG aspirates performed

•If GRV>or=250 ml, open-label, combination therapy was given. •Duration of study- 7 days.

•Successful feeding-6-hourly GRV<250 mL with a feeding rate>or=40 mL/hr


…continued

HANK OU

The only thing that interferes with my learning is my education.Albert Einstein

Aimsn To characterise antro-pyloro-duodenal motility during fasting, and in response to gastric and

duodenal nutrient,n evaluate the relationship between gastric emptying and motility, in the critically ill.

SubjectsFifteen mechanically ventilated patients from a mixed intensive care unit; 10 healthy volunteers.

•Antro-pyloro-duodenal pressures were recorded during fasting, after intragastric administration(100 ml; 100 kcal), and during small intestinal infusion of liquid nutrient (6 hours; 1 kcal/min).

•Gastricemptying was measured using a 13C octanoate breath test.

Gut 2005;54:1384-1590Antro-pyloro-duodenal response to gastric and duodenal nutrient in the critically ill patients.Chapman M, Fraser R, Vozzo R, Bryant L, Tam W, Nguyen N, Zacharakis B, Butler R, Davidson G, Horowitz M.

Methods

continued

In healthy subjects, neither gastric nor small intestinal nutrient affected antro-pyloro-duodenal pressures.

• In patients, duodenal nutrient infusion reduced antral activity compared with both fasting and healthy subjects

•Basal pyloric pressure and the frequency of phasic pyloric pressure waves were increased in patients during duodenal nutrient infusion compared with healthy subjects and with fasting

• Gastric emptying was delayed in patients and inversely related to the number of pyloric pressure waves

Stimulation of pyloric and suppression of antral pressures by duodenal nutrient are enhancedin the critically ill and related to decreased gastric emptying.


Results

Conclusions

continued

•13C octanoate breath test•100 ml octanoate was mixed with 100 ml Ensure and instilled into the stomach over five minutes

via a nasogastric tube.

• In patients, end expiratory breath samples were collected from the ventilation tube •using a T adapter (Datex-Engstrom, Helsinki, Finland) and holder for vacutainers (blood needle holder; Reko, Lisarow, Australia), •containing a needle (VenoJect; Terumo Corporation, Tokyo, Japan). This technique allowed the reliable filling of collection tubes

•(Exetainer, Buckinghamshire, UK).

•Healthy subjects fully expired into sample tubes for collection of end expiratory breath samples.

•Breath samples were collected immediately before instillation of the Ensure, every 5 minutes for the first hour, and every 15 minutes thereafter for a further 3 hours.

•Breath samples were analysed for 13CO2 concentration using an isotope ratio mass spectrometer

•The 13CO2 concentration in each sample was plotted over time andthe area under the recovery curve was used to calculate the gastric emptying coefficient(GEC).


Measurement of Gastric emptying

AIMTo examine effects of critical illness on the relationship between proximal and distal gastric motor

activity during fasting and duodenal nutrient stimulation.

n Prospective, case-controlled study.

n Ten critically ill patients and ten healthy volunteers.


: Concurrent proximal gastric (barostat) and antro-pyloro-duodenal (manometry) motility were recorded during fasting and during two 60-min duodenal nutrient infusions (at 1 kcal/min and 2 kcal/min)

in random order, separated by a 2-h wash-out period.

continued

INTERVENTIONS

•Baseline proximal gastric volumes were similar between the two groups.

•At 10 min nutrient-induced fundic relaxation was lower in patients than healthy subjects

•In patients the frequency and volume amplitude of fundic waves were also lower.

•There were fewer propagated antral waves in patients than in healthy subjects during both fasting and nutrient infusion.

•These were more retrograde, shorter in length and associated with a pyloric contraction.•

•The proportion of fundic waves followed by a distally propagated antral wave was•significantly less in patients

RESULTS

In critical illness, in addition to impairment of proximal and distal gastric motor activity, the association between the two gastric regions is abnormal.

CONCLUSIONS

continued

Outline of study technique and position of recording assemblies


Trans-mural potential

difference

Minimal distending pressure

gastrointestinal motility disorders in critically ill patients

Education