Pal Surgery

Pal Surgery · Jerusalem, Palestine

From Palestine
to the World

Open medical education for all

Surgery and the physiology underneath it, taught the way it is taught on a ward round — by a consultant surgeon, for medical students and junior doctors starting out in surgery.

Choose a topicPractise 560 MCQs

The Visual Guides series · free

Books that build from the mechanism up

  • Illustrated guides that build from the mechanism up, not from a list of causes
  • Patients to clerk — nine simulated histories, with a scored debrief
  • Bedside tools and worked examples for interpreting the tests you will order
  • Free, with a DOI — citable, printable, and licensed for teaching
Cover of Intravenous Fluids: A Practical Guide for Surgical Patients
New · freeIntravenous Fluids

Volume 3 of the series. A practical guide for surgical patients: resuscitation, maintenance and replacement, and reading the fluid balance chart. 71 pages, with twelve patients.

What’s inside
Cover of Calcium & the Parathyroid: A Visual Guide for Medical Students
Free · Volume 2Calcium & the Parathyroid

Volume 2 of the series. The calcium circuit in ten steps, then the hypercalcaemic patient, the parathyroid operation and the ward round after it. 35 pages.

What’s inside
Cover of Bile and Jaundice: A Visual Guide for Medical Students
Free · out nowBile and Jaundice

A Visual Guide for Medical Students. 31 illustrated pages on the enterohepatic circulation and the patient with jaundice — free to download, and in print.

What’s inside
Cover of Metabolic and Bariatric Surgery, Endobariatrics, and AI (IntechOpen)
Peer-reviewed · 2026AI in Bariatric Surgery

A chapter in Metabolic and Bariatric Surgery, Endobariatrics, and AI (IntechOpen), reviewing some 300 studies on machine learning in metabolic surgery.

Read the chapter
Surgery fact of the day

Source:

Since you opened this page, about0operations have been performed worldwide(estimate from about 313 million a year, Meara et al., Lancet 2015)

🏆 Weekly challenge

Can you be this week’s Surgery Champion?

Ten fast questions on clinical signs, rapid recall and real surgical scenarios. Quick right answers score more, and your best round goes on the board for every student to see.

  • 10 career levels
  • Daily challenge
  • 760 questions
  • Up to 1,500 points
  • New champion every Monday
  • Free, no sign-up
Play the Champion →

This week’s top three Live

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See the full board →
📄New · 14 topicsOne-page cheat sheetsThe high-yield facts on a single page. Print them, download the PDF, share them with your group. 🧭New · your progressMy surgery mapEvery topic on a body map that fills with colour, and turns gold, as you master it.

Surgical mnemonics

73 memory aids that make the long surgical lists stick: causes, scores, anatomy and emergencies. Flip the cards, quiz yourself, save your favourites and make your own.

MANTRELSI GET SMASHEDMALTATOM FCBUFALOThe 5 WsThe 6 PsPANCREAS
Open all 73 mnemonics →

⭐ Mnemonic of the day

Choose a topic

Every guide, every case to clerk and every calculator on the site sits under one of these. Open a topic and you get all of it in one place.

Pre-operative assessmentAssess any patient before surgery in seven steps, with the risk scores that put a number on it.7 steps9 scoresVTEAntibioticsExplore topic Liver, gallbladder & jaundiceBile acids, the three types of jaundice, liver function tests and the gallbladder patient.10 guides1 calculatorFree bookExplore topic IV fluids & electrolytesWhat bag, how much and how fast: maintenance, resuscitation, replacement, sodium and potassium.Free book1 calculator2 stationsExplore topic Acid–base & blood gasesRead any arterial blood gas in five steps: compensation, the anion gap and the surgical patterns.1 guide1 calculator10 casesExplore topic Endocrine surgeryThe thyroid and the parathyroids: the neck lump, calcium, and the patient after a thyroidectomy.ThyroidParathyroidFree bookExplore topic Bariatric & metabolic surgeryWho is a candidate, which operation, and the complications to recognise on the ward.1 guidePeer-reviewed chapterExplore topic Hernia & the abdominal wallReducible, incarcerated or strangulated; inguinal or femoral; and when it needs a surgeon tonight.1 guide2 casesExplore topic Acute abdomen & GI surgeryAbdominal pain, bowel obstruction, appendicitis and GI bleeding: the histories and the investigations.2 guides10 cases9 stationsExplore topic Vascular & woundsVenous, arterial and neuropathic ulcers, the cold leg and the diabetic foot.1 guide3 cases1 stationExplore topic Surgical oncologyHow cancer starts, spreads and is staged, the genes behind it, screening, the MDT, treatment and oncological emergencies.11 guides12-question quiz2 cheat sheetsExplore topic
Interactive · 9 cases Clerk a real surgical patient Choose your own questions, hear what the patient actually says, commit to a diagnosis — then see a scored debrief against a model clerking. New · 12 model clerkings Learn history writing Twelve complete histories and examinations as they should read on the ward, with a key box beside every part explaining why it is written that way. New · 27 OSCE stations Dry stations: imaging, results, charts, equipment and prescribing Real X-rays and scans from Radiopaedia, laboratory reports, scores, ward charts, surgical equipment and prescribing, with the examiner’s questions and model answers. Free calculators Corrected calcium & the R-factor Two numbers in, the answer out. Is this calcium really low, or is it the albumin? Is this liver injury hepatocellular or cholestatic?

The current guide

Cover of Bile and Jaundice: A Visual Guide for Medical Students

Bile and Jaundice

A Visual Guide for Medical Students · 31 pages

Why is the urine dark but the stool pale? Why does the INR rise in obstruction, and correct with vitamin K? Part 1 follows bile acids around the enterohepatic circulation in ten illustrated steps. Part 2 applies that circuit to the patient with jaundice: history, examination and laboratory interpretation.

Download the free PDF What's inside

Answers to the questions students actually ask

Each page below answers one question properly, with a diagram, the bedside relevance and a surgical pearl. Nothing is behind a sign-up.

Classic question Why are the stools pale and the urine dark? The most-asked question about jaundice, answered from the pathway up. Interpretation Reading liver function tests Three patterns, one table, and the three questions to ask of every set of results. Physiology meets ward Why the INR rises in obstructive jaundice Vitamin K needs micelles. No bile in the gut, no absorption, higher INR — and why it corrects. Examination Courvoisier's law, explained properly What it actually says, why it works, and the two exceptions examiners like. OSCE Taking a jaundice history Six questions, the exact words to say, and a model summary for the examiner. Research AI in bariatric surgery A peer-reviewed chapter reviewing 300 studies on machine learning in metabolic surgery. Commonly confused Emulsification is not micelle formation 1 µm versus 5 nm. Two stages, two jobs — and the mistake examiners notice.

Who writes this

Dr. Mohammed Maree is a consultant general, laparoscopic, bariatric and endocrine surgeon at Al-Makassed Hospital in Jerusalem, and teaches undergraduate surgery at Al-Quds University Faculty of Medicine. Everything here grew out of bedside teaching for fourth-year students on their surgical rotation.

He also publishes peer-reviewed work: a 2026 IntechOpen chapter on artificial intelligence in bariatric and endobariatric surgery reviews some 300 studies on where these models help and where they still fall short.

The guides are deposited with a DOI and licensed CC BY-NC 4.0, so any medical school may print and teach from them, with attribution. More about Pal Surgery.

Coming next

  • Acid–Base Balance — the next guide in the series
  • An MCQ bank for surgical finals and the OSCE
  • More case trainers — trauma, breast, and the acute abdomen in depth

Everything will stay free.