Digital rectal examination (DRE)

-
Digital rectal examination (DRE)

The immediate anterior relationship of the rectum in the male is the prostate. The DRE is the mainstay of examination of the prostate.

Explain the need for the examination. Ensure the examination is done in privacy. DRE is usually done in the left lateral position with the patient lying on their left side and with the hips and knees flexed to 90 degrees or more. 

Examine the anal region for fistulae and fissures. Apply plenty of lubricating gel to the gloved finger. Lift the tight buttock upwards with your other hand to expose the anus and gently and slowly insert your index finger into the anal canal and then into the rectum.

Palpate anteriorly with the pulp of your finger, and feel the surface of the prostate. Note its consistency (normal or firm), its surface (smooth or irregular), and estimate its size. (It can be helpful to relate its size to common objects (e.g. fruit or nuts!) A normal prostate is the size of a walnut, a moderately enlarged prostate that of a tangerine, and a big prostate the size of an apple or orange.) The normal bilobed prostate has a groove (the median sulcus) between the two lobes and in prostate cancer this groove may be obscured.

Many men find DRE uncomfortable or even painful and the inexperienced doctor may equate this normal discomfort with prostatic tenderness. Prostatic tenderness is best elicited by gentle pressure on the prostate with the examining finger. If the prostate is really involved by some acute, inflammatory condition such as acute, infective prostatitis or a prostatic abscess, it will be very tender.

DRE should be avoided in the profoundly neutropenic patient (risk of septicaemia) and in patients with an anal fissure (DRE would be very painful).

Other features to elicit in the DRE

The integrity of the sacral nerves that innervate the bladder and of the sacral spinal cord can be established by eliciting the bulbocavernosus reflex (the BCR) during a DRE. The sensory side of the reflex is elicited by squeezing the glans of the penis or the clitoris (or in catheterized patients, by gently pulling the balloon of the catheter onto the bladder neck). The motor side of the reflex is tested by feeling for contraction of the anus during this sensory stimulus. Contraction of the anus represents a positive BCR and indicates that the afferent and efferent nerves of the sacral spinal cord (S2 to 4) and the sacral cord are intact.

Comments

Post a Comment

Popular posts from this blog

The Nervous System, the Cerebrum

-
Image
Cerebral Cortex Basal Ganglia Limbic System Cingulate Gyrus Thalamus Hippocampus Amygdala Brain function Ability to generate information and output signals in the absence of external input. Three systems that influence output by motor systems: the sensory system monitors internal and external environments and initiates reflex responses a cognitive system voluntary responses a behavioural state system sleep-wake cycles and intrinsic behaviours The Cerebral cortex is organised into functional areas There are three functional specialisations: Sensory areas - sensory inputs Motor areas - direct muscle movement Association areas - integrate sensory and motor input and direct voluntary behavious Cerebral lateralization of function or left-right brain dominance. Neurons display a level of plasticity.  Sensory information is Integrated in the Spinal Cord and Brain Primary Somatic Sensory Cortex touch, temperature, pain, itch, and body position Visual Cortex...
Read more

The Nervous System, The Sense of Hearing

-
Image
The Tympanic Membrane and the Ossicular System Sound from the tympanic Membrane to the Cochlea Tympanic Membrane, Malleus, Incus, Stapes, Oval Window - the ossicular chain. Malleus is also attached to the tensor tympani muscle. Impedance matching between sound waves in air and sound waves in the cochlear fluid is mediated by the ossicular chain. Sound is not amplified by increasing movement at the stapes, but increasing force of movement  at the stapes. Increasing pressure, increases the vibration of the fluid in the membranous labyrinth - via the oval window.  Impedance matching between air waves and fluid waves.  Contraction of the stapedius and the tensor tympani muscles attenuates sound conduction This is the same mechanism used to diminish the sensitivity to ones own speech Increases the rigidity of the stapes, and therefore the ossicular chain. Sound Transmission Through Bone Conduction The cochlea is embedded in bone, vibration of the ...
Read more

AN UNEXPECTED CHEST XRAY

-
Image
AN UNEXPECTED CHEST XRAY Mrs MacLeod was a rather prudent 54 year old women, that presented with a shortness of breath, a chronic cough and recurrent pneumonia. She had an obstructive lung pattern on pulmonary function tests. She come in for an xray of the chest. The chest XRAY was rather different. There was unequal lung volumes, with the right lung volume being larger than the left. There was also decreased left lung vessels noted. There were no pleural effusions and no pneumothorax present either. The right lung was perfectly normal. Upon further investigation she reported to have had a significant childhood viral infection that resulted in distal airspace obstruction, probably secondary to an adenovirus or and RSV viral infection. A case of Sweyer-James syndrome was diagnosed. She was treated with influenza vaccinations, but in this case no lobectomy was performed as the no specific lung segment was identified.
Read more