Evidence Based Medicine and Examination Skills: Translating Theory to Practice

(In 3 Parts)Part 1: GastroenterologyPart 2: CardiologyPart 3: Respiratory Medicine

Neel Sharma

• Publisher: WSPC (EUROPE)
• Year: 2019
• eBook ISBN: 9781911299851
• Topic: Medicina
• Subtopic: Gastroenterologia ed epatologia

In spite of years of tuition and examination, newly qualified doctors are often left inadequately prepared for real-world clinical practice. The major concern is that 'book knowledge' gleaned at medical school does not always translate to safe and effective practical knowhow.

Based on the author's many years of expertise as an educator globally, this book helps final-year students make the difficult transition to first-year doctors. Drawing on the latest evidence-based information, it focuses on aspects important to clinical practice in the areas of gastroenterology, cardiology and respiratory medicine such as differentials, investigations and management with full references provided throughout. Also detailed are examination skills; although not the routine form of how to examine but what to be thinking when asked to examine: what conditions should be prevalent in a doctor's mind? And how can these conclusions be reached before even seeing the patient? Practical knowledge like this defines an effective clinician.

Clear, concise and rigorous in its approach, this comprehensive volume is indispensable companions to any new doctor in the above fields.

Contents:

• Gastroenterology
• Cardiology
• Respiratory Medicine

Readership: First year doctor in the fields of internal medicine: gastroenterology, respiratory, cardiology, neurology, nephrology and endocrinology.Gastroenterology;Examination Skills;Differentials;Investigations;Management;Respiratory Medicine;Cardiology00

Part I

Gastroenterology

Motility Disorders: Achalasia

Aetiopathogenesis

Achalasia is associated with gross dilatation of the oesophagus and contraction of the lower oesophageal sphincter (LOS) as well as loss of myenteric neurons. Inhibitory neurons containing vasoactive intestinal polypeptide (VIP) and nitric oxide synthase (NOS) are lost, as well as excitatory neurons containing acetylcholine. The condition is associated with a significant inflammatory response with the existence of T lymphocytes and autoantibodies. Viral factors have been linked to the disease and include measles and varicella zoster. Achalasia can also occur secondary to malignancy, Chagas’ disease, amyloidosis and sarcoidosis.

Symptoms

•Dysphagia for both liquids and solids

•Chest pain assumed to occur secondary to lactic acid production from fermentation of residual food debris

•Regurgitation secondary to retention of salvia and ingested food. Typically occurs in the recumbent position

•Weight loss

Signs

•Weight loss

•Possible chest signs secondary to aspiration

Differentials

•Angina

•Oesophageal cancer

•Oesophagitis

•Gastro-Oesophageal Reflux Disease (GORD)

•Scleroderma

•Oesophageal stricture

Investigations

An initial investigation of choice relies on a chest X-ray which typically shows an air fluid level. A barium swallow will demonstrate the classical appearances of a beak-like narrowing representing the non-relaxing LOS. Further investigations include a computed tomography (CT) scan which typically demonstrates a dilated oesophagus, and oesophageal manometry which will highlight the existence of an elevated basal LOS pressure. In some cases, however, LOS pressure may be normal or reduced. An endoscopy is useful in excluding secondary causes of achalasia such as carcinoma.

Management

Treatment comprises the use of calcium channel blockers, anti-cholinergics or nitrates which help to reduce the resting pressure of the LOS. Balloon dilatation has also been shown to reduce basal LOS pressure due to muscle fibre disruption. In some cases, patients may obtain relief from the use of endoscopic botulinum injection which helps to block cholinergic excitatory nerves in the LOS. From a surgical perspective, individuals may be able to undergo Heller myotomy which involves incision of the muscularis propria.

Diffuse Oesophageal Spasm

Aetiopathogenesis

Diffuse oesophageal spasm is thought to occur secondary to neural degeneration localised to nerve processes and inhibitory nerve dysfunction. Muscularis propria hypertrophy is also common.

Symptoms

•Chest pain

•Dysphagia

•Regurgitation

Signs

•Typically non-existent

Differentials

•Angina

•Oesophageal cancer

•Oesophagitis

•GORD

•Scleroderma

•Oesophageal stricture

Investigations

Barium swallow is the initial investigation of choice which demonstrates a corkscrew-like oesophagus. An oesophageal manometry can demonstrate the existence of swallow-induced contractions that are non-peristaltic in nature. A diagnosis is confirmed with >20% of wet swallows deteriorating into simultaneous onset contractions in the distal oesophagus.

Management

Treatment of diffuse oesophageal spasm often relies on anticholinergic agents, bougienage or botox-based therapies.

Gastro-Oesophageal Reflux Disease (GORD)

Aetiopathogenesis

One of the most common mechanisms for GORD is the occurrence of transient lower oesophageal sphincter relaxations (TLOSRs). During such activity, loss of the crural diaphragm occurs which impairs extrinsic sphincter function. Evidence also demonstrates that prolonged acid clearance is associated with worsening oesophagitis and a subsequent risk of Barrett’s oesophagus. This can occur secondary to impaired peristalsis and hypotensive contractions. Increased abdominal pressure is also linked to GORD which explains why obese individuals or pregnant women are at risk from the condition. Following meals gastric juice occupies the top of the meal close to the cardia — commonly known as the acid pocket — which in patients with GORD, is located more proximally with respect to the squamocolumnar junction. GORD patients are also noted to experience increased hypersensitivity to acid.

Symptoms

•Heartburn commonly after lying supine or bending over

•Regurgitation

•Dysphagia

•Chest pain

•Cough or wheeze secondary to aspiration of gastric contents

•Hoarseness

•Nausea

•Vomiting

Signs

•Examination is typically unremarkable

Differentials

•Motility disorders e.g. achalasia

•Oesophageal cancer

•Oesophagitis

•Gastritis

•Peptic ulcer disease

Investigations

The primary investigation of choice is an upper gastrointestinal (GI) endoscopy. This allows for detection of oesophagitis, strictures and Barrett’s oesophagus. The Los Angeles classification helps in the grading of reflux oesophagitis as follows:

•grade A oesophagitis: endoscopic abnormalities are restricted to one or more mucosal lesions with a maximum length of 5 mm.

•grade B oesophagitis: one or more mucosal breaks are present, with a maximum length of more than 5 mm but non-continuous across mucosal folds.

•grade C oesophagitis: mucosal breaks are continuous between at least two mucosal folds, but less than 75% of oesophageal circumference is involved.

•grade D oesophagitis: mucosal breaks encompass more than 75% of oesophageal circumference.

Manometry helps to determine LOS and oesophageal body function. It is undertaken in cases where there are persistence of symptoms whilst on treatment, recurrence of symptoms post-treatment, cessation as well as investigation of atypical symptoms. The use of a 24-hour pH probe is useful in cases where endoscopy is inconclusive. It helps to quantify GORD and allows for a correlation between reflux symptoms and episodes of reflux. Impedance monitoring is often used in conjunction with 24-hour pH monitoring helping to detect both acid and non-acid reflux.

Management

As per National Institute for Health and Care Excellence (NICE) guidelines, the treatment of GORD comprises proton pump inhibitors initially for up to two months followed by H2 receptor antagonists or prokinetic agents if there is a...

Table of contents

• Cover
• Halftitle
• Title
• Copyright
• Contents
• Part I Gastroenterology
• Part II Cardiology
• Part III Respiratory Medicine
• Index