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Maldigestion

Dr. H.Rustam Effendi YS,SpPD-KGEHDivisi Gastroentero-Hepatologi Departemen Ilmu Penyakit

Dalam FKUSU/RSUP.H.Adam Malik-RSU Dr. Pirngadi Medan.

30-9-2010: Kelas A dan B

Anatomi saluran cernaSmall bowel : 390-690 cm13-23ft.1ft=30cm)

Duodenum ( 5%): 50 cm (1,5ft)

Jejunum (35%): 160-280 cm (4-9ft),

leum ( 60%): 240-420 cm (8-14 ft),

Colon : 150-180 cm (5-6 ft)

Meso

lbg

Usus

haluscolon

Ligamentum Treitz

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Billiard tract obstruction caused by a gallstone in the

distal common bile duct.

Anatomy

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Proses Pencernaan

Gerakan saluran cerna.(Motilitas)

- smooth muscle constant low level of contraction (tone).

- mendorong (propulsive movements) dgn kecepatan berbeda.

- Mengaduk (mixing movements) isi sal cerna.

- Mencampur makanan dgn getah pencernaan.

- Memudahkan absorpsi nutrisi.

Sekresi :

- Kelenjar eksokrin getah pencernaan (enzim-enzim)

- Membutuhkan energi (transport aktif & sintesis)

- Getah pencernaan harus direabsorpsi ses. selesai digunakan

Pencernaan makanan : mekanikmemecah jadi ukuran kecil,

kimika(enzymatic hydrolysis)memecah jadi lebih sederhana.

(monomer, subunit), untuk memungkinkan absorpsi makanan.

Penyerapan : Transfer nutrisi hasil pencernaan dari lumen sal cerna ke dalam

pembuluh darah atau limfe.

Pembuangan (Tinja)

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FAKTOR ANATOMI DAN FISIOLOGI PENCERNAAN :

Area permukaan yang panjang & luas (12 jt /2 x 108 cm persegi)

- Mulut : gigi & lidah, amilase (hidrosisa)

- Lambung: - menggiling, mencampur, dan mendorong (

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FUNGSI SALURAN CERNA :

1.AKOMODASI ( LAMBUNG )

2.PENCERNAAN

3.ABSORBSI

4.EKSKRESI ( BAB / DEFEKASI )

Fungsi Pencernaan

Two primary function

Digestion

Absorption of nutrients and water

Digestion

Mainly in duodenum small intestine and pancreatic enzymes

Bicarbonate from pancreas neutralizes acids

Mucous protects from acids

Bile emulsifies fats

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Mengunyah (mastication/chewing), berfungsi untuk :

Memecahkan & menghaluskan makanan

memudahkan menelan

Mencampur makanan dgn saliva

Merangsang taste bud menikmati rasa makanan,

salivasi; sekresi gaster, pankreas & empedu

mempersiapkan tahap pencernaan selanjutnya

Fungsi Saliva :

salivary amylase

Mengandung lysozyme sebagai antibakteri.

Mengandung bikarbonat

foodOrganic molecules(smaller, simple)

Digested (GIT)

Biochemically Broken Down

Circulatory system

Absorbed

(GIT)

cellsECF

Makanan sumber energi,diperlukan sel utk menghasilkan ATP. ATP perlu

utk kegiatan yg memerlukan energi : spt transport aktif, kontraksi, sintesis &

sekresi.

Makanan juga berperan dalam:

a. sistem immune. b. sistem regulasi

c. regenerasi sel d. proses pertumbuhan & perkembangan

Fungsi utama sistem pencernaan mentransfer nutrisi, air &elektrolit dari makan-

an ke dlm tbh dan berperan menjaga homeostasis.

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Control of Acid Secretion

May be considered as three separate phases.

1. Cephalic phase.

2. Gastric phase.

3. Intestinal phase.

1. CEPHALIC PHASE

Sight, smell or

thought of food

Parasympathetic activation

of gastric motility & gastric juice secretion

Vagus nerve

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Food arrival causes

muscular reflexes &

gastrin secretion by G cells.

2. GASTRIC PHASE

Gastrin

GOGOFOODFOOD

Gastrin stimulates secretion from both chief &

parietal cells.

Arrival of food in duodenum

triggers release of hormones

that inhibit gastric motility &

secretions.

3. INTESTINAL PHASE

Circulation

Secretin &

Cholecystokinin (CCK)

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Ggn. FUNGSI SALURAN CERNA DAN LOLOSNYA BAHAN2 GIZI KE

TINJA SERTA PENYEBABNYA.

PENYAKIT SISTEM SALURAN CERNA

GANGGUAN FUNGSI SALURAN CERNA

GANGGUAN FUNGSI PENCERNAAN

GANGGUAN FUNGSI ABSORBSI

LOLOS BAHAN GIZI KE TINJA (SINDROMA MALABSORBSI)

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Hormones & enzyme Important in

Small Intestine Digestive Activity

Secretin

Cholecyctokinin (CCK)

Enterokinase

Pancreatic enzymes

Lipase, Amylase, Peptidases, Trypsinogen, Trypsin

Hormones Cholecystokinin secretion stimulated by fat in

duodenum

Contraction of gall bladder

Pancreatic secretion of enzyme rich material

Secretin secretion stimulated by low pH in duodenum

Secretion of bile from the liver

Pancreatic secretion of HCO3- rich juice

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Digestive enzymes Salivary amylase

Pepsin

Pancreatic enzymes: Trypsin

Chymotrypsin

Carboxypeptidase

Nucleases

Pancreatic lipase

Pancreatic amylase

Intestinal enzymes: Peptidases

Disaccharidases

Lipase

Nucleotidases

Digestion

Most occurs by hydrolysis reactions -

reactions that add water to break chemical

bonds

Enzymes involved:

amylase - breaks complex sugars to

disaccharides

lipases - breaks down lipids

proteases - breaks down proteins

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Small Intestine

Functions in digestion

CHO digestion resumes and is completed here

Protein digestion continues and completes here

Fat digestion is initiated and completed here

Also functions to absorb nutrients, fluids, and electrolytes

Divisions (@ 12 feet long total length)

duodenum = upper portion (@ 1 foot long) closest to stomach

jejunum = middle section

ileum = lower section closest to large intestine

Small Intestine

Inner surface (epithelial layer) extensively folded

and covered with smaller folds (villi) and even

smaller folds (microvilli) increase surface area for

absorption to occur

Site of absorption of carbohydrates, lipids, amino

acids, calcium and iron in duodenum and jejunum

Bile salts, Vit B12, water, and electrolytes mainly in

ileum

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CHO Digestion in Small Intestine

Pancreatic amylase secreted into duodenum in

response to secretin

Is active in the intestine because the acidic chyme

is neutralized by HCO3- also secreted from

pancreas in response to secretin

Amylase converts complex CHOs to maltriose,

maltose, and short branched sugars

Fat Digestion in Small Intestine

Limited fat digestion occurs prior to sm. Intestine

Some lipases in saliva and gastric secretions

Lipase = enzyme important in fat digestion

Secreted into sm. intestine from pancreas in response to secretin

breaks down triglycerides to free fatty acids and monoglycerides

Activity is dependent upon the amount of surface area on which it can work

Phospholipase A2 digests phospholipids

Bile is essential for proper fat digestion

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Digestion and Absorption of Lipids in

Small Intestine

Fats stimulate Intestine cell release of CCK

CCK triggers release of bile from gall bladder

Bile emulsifies fats

breaks large fat globules into smaller globules

does not actually break bonds between glycerol and fatty acids

Increases surface area available for pancreatic lipase to act

Protein Digestion in Small Intestine

Proteolytic enzymes are released (in inactive, zymogen forms) from the pancreas in response to secretin

Trypsinogen = inactive precursor that is converted (by enterokinase) to trypsin in the brush border of the small intestine

Trypsin converts other zymogens to their active forms

Collectively, the proteolytic enzymes break proteins and peptides into single amino acids, or di- and tripeptides

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Penyebab gangguan Pencernaan :

1. Kelainan lambung (Reseksi lbg, Gastritis atrofi(HCl

menurun), Gastritis autoimmune, pernicious

anemia

2. Kelainan Pankreas : Insufisiensi pankreas, Cystic

fibrosis,

3. Penyakit parenkim hati,

4. Obstruksi saluran empedu,

5. Pertumbuhan bakteri berlebihan dalam usus halus.

6. Penyakit mukosa yang luas (celiac disease, Crohn disease)

7. Infeksi, cacing, dll.

GANGGUAN PENCERNAAN

(MAL DIGESTION) :

Berkurangnya proses memecahkan makanan

( break down )

Berkurangnya proses hidrolisa bahan 2 gizi

(hidrolisis )

Diare

Steatorrhoe

Penyulit (anemia, kemunduran tulang dll )

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Dr. Rustam Effendi YS, SpPD-KGEH