TRY NOT TO GIVE NITRATES IN THE CASE OF RIGHT SIDED HEART FAILURE
THIS IS BECAUSE GTN INCREASES VENOUS CAPACITANCE
DECREASES VENOUS RETURN
as such the already weakned heart cannot utilize FRANK STARLING's LAW to increase its OUTPUT

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The Vermiform Appendix in brief:

Introduction

Acute appendicitis is the most common cause of acute abdomen in young adults
Usually happens on wakening (from experience) or so painful that the patient awakes

Anatomy
The appendix has no peristaltic capabilities
The base of the appendix is constant: the confluence of the 3 taenia coli of the caecum whcih fuse to form the outer longitudinal muscle coat of the appendix
Appendicular artery is an end artery
Location of the appendix: 6 in all
74% (3/4) Retrocecal!
21% (1/5) Pelvic
Others: Paracaecal, subcaecal, preileal, postileal

Acute Appendicitis
Introduction
Rare in infants
becomes increasingly common in childhood
reaching peak in teens and early 20s
after middle age, the risk becomes quite small
at 25 yo, males: females = 3:2 (Bailey and Love)

Aetiology:
Refer to book

Pathology: Refer to Robbins

Clinical Diagnosis
Central abdominal pain (poorly localized, colicky [though less severe than small bowel colic]) a/w nausea, anorexia and usually 1 or 2 episodes of vomiting following onset of pain
The pain is usually relieved with movement (i.e. patient is restless)
Anorexia is useful and constant especially in children
After the next 6 hours, temperature slowly rises with increased HR


Migratory Pain: periumbilical visceral to RIF somatic. this shift is only seen in 50% of acute appendicitis. Recall that for that to occur, the appendix must be anteriorly positioned. Unfortunately, 3/4 of appendices are located retrocecally.
Anorexia: constant feature, especially in children
Nausea/Vomiting: vomiting episodes (1 or 2) usually follow onset of periumbilical pain
Tenderness over RIF: localised somatic pain, worse with movement (peritoneal irritation). Localized pain in RIF is unusual in elderly. Tenderness over the RIF is only possible if the appendix is anteriorly located. In fact people with an appendix in the pelvis may instead present with suprapubic discomfort and tenesmus with tenderness elicited via DRE.
Rebound tenderness
Elevated temperature: slowly rises after 6 hours. Temperatures > 38.5*C in children, suspect other causes e.g. mesenteric adenitis
Leukocytosis
Shift to the Left

Maximal tenderness and guarding over the McBurney's point

Signs: 4 in all
1. Pointing sign (asked to point to where it began and hwere it moved).
2. Rovsing's sign
3. Psoas Sign (Usually the px presents with hips flexed due to retrocecal position of appendix sitting on and irritating the psoas muscle. Extending the hip worsens the pain)
4. Obturator sign: flex hip and internally rotate. This stretches the obturator internus. If irritated by the appendix, the pain will be felt in the suprapubic region.

Special features suggesting location
1. Retrocecal: RIF tenderness may be absent (shielded by cecum). Loin tenderness instead. rigidity of the quadratus lumborum. Psoas sign (flexed hip). Hyperextend only if hips not flexed to start with (i.e. not already in pain)
2. Pelvic: RIF pain may be absent. suprapubic pain just above and to the R of the pubic symphysis, tenesmus, diarrhea (appendix with rectum) or frequency (if in contact with the bladder) DRE = tenderness in POD or rectovesical pouch on the R side. Psoas and obturator sign may be present.
3. Post ileal: diarrhea and retching. Tenderness to the R of the umbilicus.

Special features according to age

Elderly: localized pain in RIF is unusual
Obese
Pregnant

Investigations
Lab:
FBC, U/E/Cr, UPT, Urinalysis
Imaging studies
Abdominal ultrasound
CT scan when met with diagnostic uncertainty

Management:
Alvarado score (for Emergency departments w/o CT scans)
The scores will determine whether or not to request for urgent GS registrar referral
7-10: high risk
4-7: moderate risk
1-3: d/c with advice to return

Treatment
Appendicectomy
Complications
- Rupture
- Appendiceal mass to rupture later
- Abscess
- spread into portal circulation
- Fistula formation

Common Caveats in Emergency Medicine Diagnoses:



1. Appendicitis misdiagnosed as Acute Gastroenteritis: AGE

Professor Manning mentioned a study in a hospital in the USA which revealed that high percentages (can't remember exact figures) of appendicitis cases were misdiagnosed as AGE. Prof Manning jokingly explained that it was probably because AGE is an easier and more convenient diagnosis (no need for observation or further hospital stays!) compared to acute appendicitis!



Anyway, i've been taught that the classical presentation of appendicitis is that of poorly localized periumbilical pain migrating towards the RIF to become a well localized area of sharp stabbing pain and tenderness. This classical teaching raises 3 issues:



(i) What is classical isn't the commonest: this only applies if the appendix lies anterior to the cecum. The appendix, however, is most often located retrocecally

(ii) A well localized pain: if a person has a well localized area of pain and tenderness,

(iii) Risk of perforation: atypical presentations commonly confuse the physician and results in misdiagnoses. As often mentioned, the very young have difficulties in expressing themselves resultign in diagnostic difficulties. The elderly suffer from the same problems, and are also guilty of atypical presentations (E.g. a large majority of them do not have fever or raised WCC during an infective process). Other atypical presentations include the pregnant women, where the area of pain may not be at the RIF but instead, pushed by the gravid uterus, be located at the Right hypochondrium and as such, is often misdiagnosed as cholecystitis.



To help a physician with diagnosing acute appendicitis: The Alvarado Score

Alvarado = MANTRELS



Migratory pain: 1 point

Anorexia: 1 point

Nausea/Vomiting: 1 point

Tenderness at RIF: 2 points: this shows the emphasis of a localized area of pain (which if present, is very unlikely AGE)

Rebound tenderness 1 point

Elevated Temp: 1 point

Leukocytosis: 2 points (do note that in a large number of elderly patients, WCC isn't raised)

Shift to the Left: 1 point



There are opponents to the usage of Alvarado score in the diagnosis of appendicitis. Well these people are aka the surgeons. Well when stuck in the emergency department and not having a CT scan readily available (unlike the surgical dudes), alvarado score is immensely precious.



7-10: high risk, surgical referral STAT (Surgical Reg pls)

4-6: moderate risk: EDTU for serial observation and wait for Surgical Reg to R/V

1-3: low risk of appendicitis: discharge, explain that it is unlikely appendicitis, that the risk of appendicitis developing over the next 24 hours is equivalent to my own. Tell the patient to return the following morning (12-24 hours later) or when the pain gets worse.



2. Ectopic pregnancy:



Risk factors: basically anything that disrupts the anatomy and function of the hoohoos

(i) PID (increasingly common in Singapore, especially Chlamydia infections)

(ii) Previous surgery/Ashermann's syndrome

(iii) Infertility (duh)

(iv) previous ectopic pregs

(v) endometriosis



95% of ectopic pregnancies are tubal pregnancies

Contrary to common misconception, the more distal the tubal pregnancy is actually safer than those involving mroe proximal sections of the oviduct. Why?

- Ampulla: commonest site of tubal pregnancy. The isthmus is the least common i think. The reason why tubal pregnancy at the isthmus is so dangerous is because the ovarian artery and its big branches are in close proximity to the oviductal isthmus. Subsequent invasion and perforation of these arteries may result in massive haemorrhage, much more so than that of tubal pregnancies involving the ampulla.



Classical presentation: Like appendicitis, classical is not neccessarily the commonest. In fact in ectopic pregnancy, the classical triad below only happens in 25% of the cases

(i) Lower abdominal pain

(ii) Vaginal spotting (NOT FRANK BLEED! just vaginal spotting! the bleed is internal!)

(iii) adnexal mass



On examination: DVE (vaginal examination)

- adnexal mass

- cervical motion tenderness (peritoneal sign)

- uterine enlargement (for those not known to be pregnant) or uterus small for age (for those who are pregnant)



What to do?:

(i) Estabilish if the bleed is part of her normal menstrual cycle: Time, duration, volume

(ii) do a UPT! Nurses in NUH A and E are empowered by Prof Manning to do UPTs. They are very cheap, easy to carry out, sensitive, specific and can detect raised hCG as early as 7-10 days after fertilization! (older models detect 2 weeks later). uhCG 15-50mIU/ml = 95-100% sensitive and specific.

(iii) 14/16 G 2x large bore IV cannulae

(iv) GXM (for E blood)



Simple Rules of Thumb:

Young women + syncope + abdominal pain: Ectopic pregnancy

Young persons + syncope + headache: SAH

Old + syncope + abdominal pain = AAA

Old + syncope + chest pain + diaphoresis = AMI



Musings: When asked how much blood is lost in a patient with ectopic pregnancy, say 1.5L! Why? nobody knows. its like an O and G rule. 1.5 L. As though these specialists have fingers made of measuring tubes.



Other killers with abdominal pain:

1. AAA:

- classical Pxn: Pentad: old + pulsatile abdominal mass + collapse + back pain radiating to abdomen (or vice versa) + hypotension

- Mx: U/S



2. Mesenteric Ischaemia

- post prandial pain + pain out of proportion (rolls around) + co morbidities (anything that results in low CO: CCF, dehydration, elderly) + blood in rectum (late sign: prepare the undertakers)

Mx: bedside lactate = raised due to metabolic acidosis



3. Perforated Viscus

- Gastric aetiologies

- Perforated malignancy

Pxn: Abdo pain + patient keeps still (peritoneal irritation) + guarding

Mx: erect/decubitus CXR/AXR



4. Pancreatitis: A triad

Pxn:

(i) patient sits up, hunched forward, or lying on his side: Why? ==> Pancreas is a retroperitoneal organ. this is to allow relieve of pressure of the lumbar spine against which the pancreas is pressed against

(ii) Epigastric pain radiating to the back

(iii) Vomiting: this is especially important. in fact, Prof Manning mentioned that without vomiting, pancreatitis is less likely the cause of abdominal pain, thus no need to order amylase or lactase

5. Intestinal Obstriuction

6. Extraabdominal causes:

- inferior MI

- basilar pneumonia: diaphragm has multiple innervations, referred pain to epigastrium

- DKA

- ureteric colic, testicular torsion

- Methanol poisoning: Russian sailors, drunk + abdopain + blindness




Quiz of the Day:
Now i have a quiz for everyone here. The answers at the bottom so try not to look at it.
An elderly gentlemen came into the A and E presenting with:
(i) colicky loin to groin pain
(ii) blood in urine
(iii) abdominal pain
On further questioning:
(i) no previous history of stones
(ii) first episode of the presentation described above
SO whats your DIAGNOSIS?

ANSWER:
aaa lanerarpus
aaa lla fo %2