Procedures

Central Venous Line
A central venous catheter ("central line", "CVC", "central venous line" or "central venous access catheter") is a catheter placed into a large vein in the neck (internal jugular vein), chest (subclavian vein) or groin (femoral vein). It is used to administer medication or fluids, obtain blood tests (specifically the "mixed venous oxygen saturation"), and directly obtain cardiovascular measurements such as the central venous pressure. Certain medications, such as inotropes and amiodarone, are preferably given through a central line.
Types
There are several types of central venous catheters
Tunneled catheter
This type of catheter is inserted into a vein at one location (neck, chest or groin), and tunneled under the skin to a separate exit site, where it emerges from underneath the skin. It is held in place by a Dacron cuff, just underneath the skin at the exit site. The exit site is typically located in the chest, making the access ports less visible than if they were to directly protrude from the neck. Passing the catheter under the skin helps to prevent infection and provides stability.
Implanted port


Implanted port
A port is similar to a tunneled catheter but is left entirely under the skin. Medicines are injected through the skin into the catheter. Some implanted ports contain a small reservoir that can be refilled in the same way. After being filled, the reservoir slowly releases the medicine into the bloodstream. An implanted port is less obvious than a tunneled catheter and requires very little daily care. It has less impact on a person's activities than a PICC line or a tunneled catheter. Surgically implanted infusion port placed below the clavicle (infraclavicular fossa), catheter threaded into the right atrium through large vein. Accessed via non-coring "Huber" needle through the skin. May need to use topical anesthetic prior to accessing port. Used for medications, chemotherapy, TPN, and blood. Easy to maintain for home-based therapy.
PICC line
A peripherally inserted central catheter, or PICC line (pronounced "pick"), is a central venous catheter inserted into a vein in the arm rather than a vein in the neck or chest.
Technical description


Triluminal catheter
Dependent on its use, the catheter is monoluminal, biluminal or triluminal, dependent on the actual number of tubes or lumens (1, 2 and 3 respectively). Some catheters have 4 or 5 lumens, depending on the reason for their use.
The catheter is usually held in place by a suture or staple and an occlusive dressing. Regular flushing with saline or a heparin-containing solution keeps the line patent and prevents thrombosis. Certain lines are impregnated with antibiotics, silver-containing substances (specifically silver sulfadiazine) and/or chlorhexidine to reduce infection risk.
Specific types of long-term central lines are the Hickman catheters, which require clamps to make sure the valve is closed, and Groshong catheters, which have a valve that opens as fluid is withdrawn or infused and remains closed when not in use. Hickman and Groshong lines need more specific measures to prevent infection. Hence, they are inserted into the jugular vein but then tunneled under the skin to maximize the distance a pathogen would need to travel to enter the bloodstream. Hickman lines also have a "cuff" under the skin, again to prevent bacterial migration.[citation needed]
Indications and uses
Indications for the use of central lines include
• Monitoring of the central venous pressure (CVP) in acutely ill patients to quantify fluid balance
• Long-term Intravenous antibiotics
• Long-term Parenteral nutrition especially in chronically ill patients
• Long-term pain medications
• Chemotherapy
• Drugs that are prone to cause phlebitis in peripheral veins (caustic), such as:
o Calcium chloride
o Chemotherapy
o Hypertonic saline
o Potassium chloride
o Amiodarone
• Plasmapheresis
• Dialysis
• Frequent blood draws
• Frequent or persistent requirement for intravenous access
• Need for intravenous therapy when peripheral venous access is impossible
o Blood
o Medication
o Rehydration
Central venous catheters usually remain in place for a longer period of time, especially when the reason for their use is longstanding (such as total parenteral nutrition in a chronically ill patient). For such indications, a Hickman line, a PICC line or a portacath may be considered because of their smaller infection risk. Sterile technique is highly important here, as a line may serve as a porte d'entrée (place of entry) for pathogenic organisms, and the line itself may become infected with organisms such as Staphylococcus aureus and coagulase-negative Staphylococci.[citation needed]
Insertion


Triple lumen in jugular vein
The skin is cleaned, and local anesthetic applied if required. The location of the vein is then identified by landmarks or with the use of a small ultrasound device. A hollow needle is advanced through the skin until blood is aspirated; the color of the blood and the rate of its flow help distinguish it from arterial blood (suggesting that an artery has been accidentally punctured).[citation needed]
The Seldinger technique is then employed to insert the line. This means that a blunt guidewire is passed through the needle, and the needle is then removed. A dilating device may be passed over the guidewire to slightly enlarge the tract, and the central line itself is then passed over the guidewire, which is then removed. All the lumens of the line are aspirated (to ensure that they are all positioned inside the vein) and flushed.[citation needed]
For jugular and subclavian lines, a chest X-ray is typically performed to ensure the line is positioned inside the superior vena cava and, in the case of insertion through the subclavian vein, that there is no resultant pneumothorax.
Complications
Central line insertion may cause a number of complications. The benefit expected from their use therefore needs to outweigh the risk of those complications.
Pneumothorax
Pneumothorax (for central lines placed in the chest); the incidence is thought to be higher with subclavian vein catheterization. In catheterization of the internal jugular vein, the risk of pneumothorax can be minimized by the use of ultrasound guidance. For experienced clinicians, the incidence of pneumothorax is about 1%. Some official bodies, e.g. the National Institute for Health and Clinical Excellence (UK), recommend the routine use of ultrasonography to minimize complications
Infection
All catheters can introduce bacteria into the bloodstream, but CVCs are known for occasionally causing Staphylococcus aureus and Staphylococcus epidermidis sepsis. Infection risks were initially thought to be less in jugular lines, but this only seems to be the case if the patient is obese
If a patient with a central line develops signs of infection, blood cultures are taken from both the catheter and from a vein elsewhere in the body. If the culture from the central line grows bacteria much earlier (>2 hours) than the other site, the line is the likely source of the infection. Quantitative blood culture is even more accurate, but this is not widely available
Generally, antibiotics are used, and occasionally the catheter will have to be removed. In the case of bacteremia from Staphylococcus aureus, removing the catheter without administering antibiotics is not adequate as 38% of such patients may still develop endocarditis.
In a clinical practice guideline, the American Centers for Disease Control and Prevention recommends against routine culturing of central venous lines upon their removal. The guideline makes a number of further recommendations to prevent line infections.
To prevent infection, stringent cleaning of the catheter insertion site is advised. Povidone-iodine solution is often used for such cleaning, but chlorhexidine appears to be twice as good as iodine. Routine replacement of lines makes no difference in preventing infection.
Other complications
Rarely, small amounts of air are sucked into the vein as a result of the negative intrathoracic pressure.[citation needed] If these air bubbles obstruct blood vessels, this is known as an air embolism.
Hemorrhage (bleeding) and formation of a hematoma (bruise) is slightly more common in jugular venous lines than in others.
Arrhythmia may occur during the insertion process when the wire comes in contact with the endocardium. It typically resolved when the wire is pulled back.



Arterial catheter
An arterial line, or art-line, is a thin catheter inserted into an artery. It is most commonly used in intensive care medicine to monitor the blood pressure real-time (rather than by intermittent measurement), and to obtain samples for arterial blood gas measurements. It is not generally used to administer medication.
An arterial line is usually inserted in the wrist (radial artery); but can also be inserted into the elbow (brachial artery), groin (femoral artery), foot (dorsalis pedis artery).

Insertion is often painful; however an anesthetic such as Lidocaine can be used to make the insertion more tolerable, but this can make insertion more difficult.
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Implantable Cardioverter Defibrillator (ICD) Insertion
The heart's electrical conduction system

The heart is, in the simplest terms, a pump made up of muscle tissue. Like all pumps, the heart requires a source of energy in order to function. The heart's pumping energy comes from an indwelling electrical conduction system.
An electrical stimulus is generated by the sinus node (also called the sinoatrial node, or SA node), which is a small mass of specialized tissue located in the right atrium (right upper chamber) of the heart.
The sinus node generates an electrical stimulus regularly at 60 to 100 times per minute under normal conditions. This electrical stimulus travels down through the conduction pathways (similar to the way electricity flows through power lines from the power plant to your house) and causes the heart's chambers to contract and pump out blood.
The right and left atria (the two upper chambers of the heart) are stimulated first and contract a short period of time before the right and left ventricles (the two lower chambers of the heart).
The electrical impulse travels from the sinus node to the atrioventricular (AV) node, where it stops for a very short period, then continues down the conduction pathways via the "bundle of His" into the ventricles. The bundle of His divides into right and left pathways to provide electrical stimulation to both ventricles.
Reasons for the Procedure
A pacemaker may be inserted in order to provide stimulation for a faster heart rate when the heart is beating too slowly, and when other treatment methods, such as medication, have not improved the heart rate.
An ICD may be inserted in order to provide fast pacing (ATP), cardioversion (small shock), or defibrillation (larger shock) when the heart beats too fast.
Problems with the heart rhythm may cause difficulties because the heart is unable to pump an adequate amount of blood to the body. If the heart rate is too slow, the blood is pumped too slowly.
If the heart rate is too fast or too irregular, the heart chambers are unable to fill up with enough blood to pump out with each beat. When the body does not receive enough blood, symptoms such as fatigue, dizziness, fainting, and/or chest pain may occur.
Some examples of rhythm problems for which a pacemaker or ICD might be inserted include:
• atrial fibrillation - occurs when the atria beat irregularly and too fast
• ventricular fibrillation - occurs when the ventricles beat irregularly and too fast
• bradycardia - occurs when the heart beats too slow
• tachycardia - occurs when the heart beats too fast
• heart block - occurs when the electrical signal is delayed after leaving the SA node; there are several types of heart blocks, and each one has a distinctive ECG tracing
There may be other reasons for your physician to recommend a pacemaker or ICD insertion.
Risks of the Procedure
Possible risks of pacemaker or ICD insertion include, but are not limited to, the following:
• bleeding from the incision or catheter insertion site
• damage to the vessel at the catheter insertion site
• infection of the incision or catheter site
• pneumothorax - air becomes trapped in the pleural space causing the lung to collapse
If you are pregnant or suspect that you may be pregnant, you should notify your physician. If you are lactating, or breastfeeding, you should notify your physician.
Patients who are allergic to or sensitive to medications or latex should notify their physician.
For some patients, having to lie still on the procedure table for the length of the procedure may cause some discomfort or pain.
There may be other risks depending upon your specific medical condition. Be sure to discuss any concerns with your physician prior to the procedure.

Before the Procedure
• Your physician will explain the procedure to you and offer you the opportunity to ask any questions that you might have about the procedure.
• You will be asked to sign a consent form that gives your permission to do the test. Read the form carefully and ask questions if something is not clear.
• You will need to fast for a certain period of time prior to the procedure. Your physician will notify you how long to fast, usually overnight.
• If you are pregnant or suspect that you are pregnant, you should notify your physician.
• Notify your physician if you are sensitive to or are allergic to any medications, iodine, latex, tape, or anesthetic agents (local and general).
• Notify your physician of all medications (prescription and over-the-counter) and herbal supplements that you are taking.
• Notify your physician if you have heart valve disease, as you may need to receive an antibiotic prior to the procedure.
• Notify your physician if you have a history of bleeding disorders or if you are taking any anticoagulant (blood-thinning) medications, aspirin, or other medications that affect blood clotting. It may be necessary for you to stop some of these medications prior to the procedure.
• Your physician may request a blood test prior to the procedure to determine how long it takes your blood to clot. Other blood tests may be done as well.
• You may receive a sedative prior to the procedure to help you relax. If a sedative is given, you will need someone to drive you home afterwards.
• The upper chest may be shaved or clipped prior to the procedure.
• Based upon your medical condition, your physician may request other specific preparation.
During the Procedure

Chest X-ray with Implanted Pacemaker
A pacemaker or implanted cardioverter defibrillator may be performed on an outpatient basis or as part of your stay in a hospital. Procedures may vary depending on your condition and your physician's practices.
Generally, a pacemaker or ICD insertion follows this process:
1. You will be asked to remove any jewelry or other objects that may interfere with the procedure.
2. You will be asked to remove your clothing and will be given a gown to wear.
3. You will be asked to empty your bladder prior to the procedure.
4. An intravenous (IV) line will be started in your hand or arm prior to the procedure for injection of medication and to administer IV fluids, if needed.
5. You will be placed in a supine (on your back) position on the procedure table.
6. You will be connected to an electrocardiogram (ECG or EKG) monitor that records the electrical activity of the heart and monitors the heart during the procedure using small, adhesive electrodes. Your vital signs (heart rate, blood pressure, breathing rate, and oxygenation level) will be monitored during the procedure.
7. Large electrode pads will be placed on the front and back of the chest.
8. You will receive a sedative medication in your IV before the procedure to help you relax. However, you will likely remain awake during the procedure.
9. The pacemaker or ICD insertion site will be cleansed with antiseptic soap.
10. Sterile towels and a sheet will be placed around this area.
11. A local anesthetic will be injected into the skin at the insertion site.
12. Once the anesthetic has taken effect, the physician will make a small incision at the insertion site.
13. A sheath, or introducer, is inserted into a blood vessel, usually under the collarbone. The sheath is a plastic tube through which the pacer/ICD lead wire will be inserted into the blood vessel and advanced into the heart.
14. It will be very important for you to remain still during the procedure so that the catheter placement will not be disturbed and to prevent damage to the insertion site.
15. The lead wire will be inserted through the introducer into the blood vessel. The physician will advance the lead wire through the blood vessel into the heart.
16. Once the lead wire is inside the heart, it will be tested to verify proper location and that it works. There may be one, two, or three lead wires inserted, depending on the type of device your physician has chosen for your condition. Fluoroscopy, (a special type of x-ray that will be displayed on a TV monitor), may be used to assist in testing the location of the leads.
17. Once the lead wire has been tested, an incision will be made close to the location of the catheter insertion (just under the collarbone). You will receive local anesthetic medication before the incision is made.
18. The pacemaker/ICD generator will be slipped under the skin through the incision after the lead wire is attached to the generator. Generally, the generator will be placed on the non-dominant side. (If you are right-handed, the device will be placed in your upper left chest. If you are left-handed, the device will be placed in your upper right chest).
19. The ECG will be observed to ensure that the pacer is working correctly.
20. The skin incision will be closed with sutures, adhesive strips, or a special glue.
21. A sterile bandage/dressing will be applied.
After the Procedure
In the hospital
After the procedure, you may be taken to the recovery room for observation or returned to your hospital room. A nurse will monitor your vital signs for a specified period of time.
You should immediately inform your nurse if you feel any chest pain or tightness, or any other pain at the incision site.
After the specified period of bed rest has been completed, you may get out of bed. The nurse will assist you the first time you get up, and will check your blood pressure while you are lying in bed, sitting, and standing. You should move slowly when getting up from the bed to avoid any dizziness from the period of bedrest.
You will be able to eat or drink once you are completely awake.
The insertion site may be sore or painful, but pain medication may be administered if needed.
Your physician will visit with you in your room while you are recovering. The physician will give you specific instructions and answer any questions you may have.
Once your blood pressure, pulse, and breathing are stable and you are alert, you will be taken to your hospital room or discharged home.
If the procedure is performed on an outpatient basis, you may be allowed to leave after you have completed the recovery process. However, if there are concerns or problems with your ECG, you may stay in the hospital for an additional day (or longer) for monitoring of the ECG.
You should arrange to have someone drive you home from the hospital following your procedure.
At home
You should be able to return to your daily routine within a few days. Your physician will tell you if you will need to take more time in returning to your normal activities. In addition, you should not do any lifting or pulling on anything for a few weeks. You may be instructed not to lift your arms above your head for a period of time.
You will most likely be able to resume your usual diet, unless your physician instructs you differently.
It will be important to keep the insertion site clean and dry. Your physician will give you specific bathing instructions.
Your physician will give you specific instructions about driving. If you had an ICD, you will not be able to drive until your physician gives you approval. Your physician will explain these limitations to you, if they are applicable to your situation.
You will be given specific instructions about what to do if your ICD discharges a shock. For example, you may be instructed to dial 911 or go to the nearest emergency room in the event of a shock from the ICD.
Ask your physician when you will be able to return to work. The nature of your occupation, your overall health status, and your progress will determine how soon you may return to work.
Notify your physician to report any of the following:
• fever and/or chills
• increased pain, redness, swelling, or bleeding or other drainage from the insertion site
• chest pain/pressure, nausea and/or vomiting, profuse sweating, dizziness and/or fainting
• palpitations
Your physician may give you additional or alternate instructions after the procedure, depending on your particular situation.


Foley catheter

Foley catheters are flexible (usually latex) tubes that are passed through the urethra during urinary catheterization and into the bladder to drain urine. They are retained by means of a balloon at the tip which is inflated with sterile water. The balloons typically come in two different sizes: 5 cc and 30 cc. They are commonly made in silicone rubber or natural rubber.
The relative size of a Foley catheter is described using French units (F).[1] The most common sizes are 10 F to 28 F. 1 F is equivalent to 0.33 mm = .013" = 1/77" of diameter. Thus the size in French units is roughly equal to the circumference of the catheter in millimetres.


Side view diagram of male urinary tract with Foley catheter in place to drain urine. A balloon near the tip holds the catheter in place.
Foley catheter (F/Ch. 24) positioned in a male; balloon blocked and outlet plug put on.
Foley catheters come in several sub-types. Coudé (French for elbowed) catheters have a 45° bend at the tip to allow easier passage through an enlarged prostate. Council tip catheters have a small hole at the tip which allows them to be passed over a wire. 3-way catheters are used primarily after bladder, prostate cancer or prostate surgery. They have a third arm or bell that allows an irrigant to pass to the tip of the catheter through a small separate channel into the bladder. This serves to wash away blood and small clots through the primary arm that drains into a collection device. This prevents larger clots, which might plug the catheter, from forming. The second, or inflation, arm has a small plastic valve that allows for the introduction or removal of sterile water through a very small channel to inflate or deflate the retaining balloon.
Foley catheters can also be used to "ripen" the cervix, to allow the induction of labour. The catheter is inserted behind the cervical wall and inflated. The remaining length of the catheter is gently pulled and taped to the inside of the woman's leg. The inflated balloon applies pressure to the cervix, like the baby's head would prior to labour, causing it to dilate. Over time the catheter is adjusted and re-taped to maintain pressure on the cervix. When the cervix has dilated sufficiently, the catheter simply drops out.
They were designed by Frederic Foley, a surgeon working in Boston, Massachusetts, in the 1930s, when he was a medical student
His original design was adopted by C. R. Bard, Inc. of Murray Hill, New Jersey, who manufactured the first prototypes and named them in honor of the surgeon.
A major problem with Foley catheters is that they have a tendency to contribute to urinary tract infections (UTI). This occurs because bacteria can travel up the catheters to the bladder where the urine can become infected. To combat this, the industry is moving to antibiotic coated catheters. This has been helpful, but it has not completely solved this major problem. An additional problem is that Foley catheters tend to become coated over time with a biofilm that can keep them from properly draining the bladder. This increases the degree of static urine left in the bladder, which further contributes to the problem of urinary tract infections. When a Foley catheter becomes clogged, it must be flushed or replaced. Thus keeping Foley Catheters from clogging may help reduce UTIs as well.
When Foley catheters are used
Foley catheters are used during the following situations:
• On patients who are anesthesized or sedated for surgery or other medical care
• On comatose patients
• On some incontinent patients
• On patients whose prostate is enlarged to the point that urine flow from the bladder is cut off. The catheter is kept in until the problem is resolved.
• On patients with acute urinary retention.
• On patients who are unable due to paralysis or physical injury to use either standard toilet facilities or urinals.
• Following urethral surgeries
• Following uretectomy
• Sometimes before Furosemide administration
Alternative treatments
• For obstructed prostates due to BPH: The Spanner Prostatic stent


Lumbar puncture



A patient undergoes a lumbar puncture at the hands of a neurologist. The reddish-brown swirls on the patient's back are tincture of iodine (an antiseptic).
In medicine, a lumbar puncture (colloquially known as a spinal tap) is a diagnostic and at times therapeutic procedure that is performed in order to collect a sample of cerebrospinal fluid (CSF) for biochemical, microbiological, and cytological analysis, or very rarely as a treatment ("therapeutic lumbar puncture") to relieve increased intracranial pressure.

Indications
The most common purpose for a lumbar puncture is to collect cerebrospinal fluid in a case of suspected meningitis, since there is no other reliable tool with which meningitis, a life-threatening but highly treatable condition, can be excluded. Young infants commonly require lumbar puncture as a part of the routine workup for fever without a source, as they have a much higher risk of meningitis than older persons and do not reliably show signs of meningeal irritation (meningismus). In any age group, subarachnoid hemorrhage, hydrocephalus, benign intracranial hypertension and many other diagnoses may be supported or excluded with this test.
Lumbar punctures may also be done to inject medications into the cerebrospinal fluid ("intrathecally"), particularly for spinal anesthesia or chemotherapy.It may also be used to detect the presence of malignant cells in the CSF,as in carcinomatous meningitis or medulloblastoma. Lumbar punctures can be unpleasant for some people, due to increased sensitivity when the needle is inserted to collect the cerebrospinal fluid.
Contraindications
Lumbar puncture should not be performed when idiopathic (unidentified cause) increased intracranial pressure (ICP) is present. The exception is therapeutic use of lumbar puncture to relieve ICP. Ideally, a CT scan should be performed prior to lumbar puncture to rule out space occupying lesions. Ophthalmoscopy for papilledema should also be performed prior to any LP to check for ICP. Also, lumbar puncture should not be attempted when there is coagulopathy, abnormal respiratory pattern,hypertension with bradycardia and deteriorating consciousness or when there are decreased levels of platelets in the blood (less than 50 x 109/L). Lumbar puncture in cases of vertebral deformities (scoliosis or kyphosis) is also contraindicated in hands of an unexperienced physician.[1][2]

Procedure


Spinal needles used in lumbar puncture.
In performing a lumbar puncture, first the patient is usually placed in a left (or right) lateral position with his/her neck bent in full flexion and knees bent in full flexion up to his/her chest, approximating a fetal position as much as possible. It is also possible to have the patient sit on a stool and bend his/her head and shoulders forward. The area around the lower back is prepared using aseptic technique. Once the appropriate location is palpated, local anaesthetic is infiltrated under the skin and then injected along the intended path of the spinal needle. A spinal needle is inserted between the lumbar vertebrae L3/L4 or L4/L5 and pushed in until there is a "give" that indicates the needle is past the dura mater. The needle is again pushed until there is a second 'give' that indicates the needle is now past the arachnoid mater, and in the subarachnoid space. The stylet from the spinal needle is then withdrawn and drops of cerebrospinal fluid are collected. The opening pressure of the cerebrospinal fluid may be taken during this collection by using a simple column manometer. The procedure is ended by withdrawing the needle while placing pressure on the puncture site. In the past, the patient would often be asked to lie on his/her back for at least six hours and be monitored for signs of neurological problems, though there is no scientific evidence that this provides any benefit. The technique described is almost identical to that used in spinal anesthesia, except that spinal anesthesia is more often done with the patient in a sitting position.
The upright seated position is advantageous in that there is less distortion of spinal anatomy which allows for easier withdrawal of fluid. It is preferred by some practitioners when a lumbar puncture is performed on an obese patient where having them lie on their side would cause a scoliosis and unreliable anatomical landmarks. On the other hand, opening pressures are notoriously unreliable when measured on a seated patient and therefore the left or right lateral (lying down) position is preferred if an opening pressure needs to be measured.
Patient anxiety during the procedure can lead to increased CSF pressure, especially if the person holds their breath, tenses their muscles or flexes their knees too tightly against their chest. Diagnostic analysis of changes in fluid pressure during lumbar puncture procedures requires attention both to the patient's condition during the procedure and to their medical history.[
Reinsertion of the stylet may decrease the rate of post lumbar puncture headaches.










Thoracocentesis or Pleural Tap
Thoracentesis (pronounced /ˌθɔrəsɨnˈtiːsɨs/) (also known as thoracocentesis or pleural tap) is an invasive procedure to remove fluid or air from the pleural space for diagnostic or therapeutic purposes. A cannula, or hollow needle, is carefully introduced into the thorax, generally after administration of local anesthesia. The procedure was first described in 1852.
The recommended location varies depending upon the source. It is critical that the patient holds their breath to avoid piercing the lung. Some sources recommend the midaxillary line, in the ninth intercostal space.


Chest X-ray showing a left-sided pleural effusion (right side of image). This can be treated with thoracentesis.



The illustration shows a person having thoracentesis. The person sits upright and leans on a table. Excess fluid from the pleural space is drained into a bag.

Indications
This procedure is indicated when unexplained fluid accumulates in the chest cavity outside the lung. In more than 90% of cases analysis of pleural fluid yields clinically useful information. If a large amount of fluid is present, then this procedure can also be used therapeutically to remove that fluid and improve patient comfort and lung function.
The most common causes of pleural effusions are cancer, congestive heart failure, pneumonia, and recent surgery. In countries where tuberculosis is common, this is also a common cause of pleural effusions.
When cardiopulmonary status is compromised (i.e. when the fluid or air has its repercussions on the function of heart and lungs), due to air (significant pneumothorax), fluid (pleural fluid) or blood (hemothorax) outside the lung, then this procedure is usually replaced with tube thoracostomy, the placement of a large tube in the pleural space.
Contraindications
An uncooperative patient or a coagulation disorder that can not be corrected are absolute contraindications.
Relative contraindications include cases in which the site of insertion has known bullous disease (e.g. emphysema), use of positive end-expiratory pressure (PEEP, see mechanical ventilation) and only one functioning lung (due to diminished reserve). The aspiration should not exceed 1L as there is a risk of development of pulmonary edema.
Complications
Major complications are pneumothorax (3-30%), hemopneumothorax, hemorrhage, hypotension (low blood pressure due to a vasovagal response) and reexpansion pulmonary edema.
Minor complications include a dry tap (no fluid return), subcutaneous hematoma or seroma, anxiety, dyspnea and cough (after removing large volume of fluid).
The use of ultrasound for needle guidance can minimize the complication rate.
Interpretation of pleural fluid analysis
Several diagnostic tools are available to determine the etiology of pleural fluid.
Transudate versus exudate
First the fluid is either transudate or exudate.
A transudate is defined as pleural fluid to serum total protein ratio of less than 0.5, pleural fluid to serum LDH ratio < 0.6, and absolute pleural fluid LDH < 200 IU or < 2/3 of the normal serum.
An exudate is any fluid that filters from the circulatory system into lesions or areas of inflammation. It can apply to plants as well as animals. Its composition varies but generally includes water and the dissolved solutes of the main circulatory fluid such as sap or blood. In the case of blood: it will contain some or all plasma proteins, white blood cells, platelets and (in the case of local vascular damage) red blood cells.
Exudate
• hemorrhage
• Infection
• Inflammation
• Malignancy
• Iatrogenic
• Connective tissue disease
• Endocrine disorders
• Lymphatic disorders vs Constrictive pericarditis
Transudate
• Congestive heart failure
• Nephrotic syndrome
• Hypoalbuminemia
• Cirrhosis
• Atelectasis
• trapped lung
• Peritoneal dialysis
• Superior vena cava obstruction
Amylase
A high amylase level (twice the serum level or the absolute value is greater than 160 Somogy units) in the pleural fluid is indicative of either acute or chronic pancreatitis, pancreatic pseudocyst that has dissected or ruptured into the pleural space, cancer or esophageal rupture.
Glucose
This is considered low if pleural fluid value is less than 50% of normal serum value. The differential diagnosis for this is:
• rheumatoid effusion.The levels are characteristically low (<15 mg/dL).
• lupus effusion
• bacterial empyema
• malignancy
• tuberculosis
• esophageal rupture (Boerhaave syndrome)
pH
Normal pleural fluid pH is approximately 7.60. A pleural fluid pH below 7.30 with normal arterial blood pH has the same differential diagnosis as low pleural fluid glucose.
Triglyceride and cholesterol
Chylothorax (fluid from lymph vessels leaking into the pleural cavity) may be identified by determining triglyceride and cholesterol levels, which are relatively high in lymph. A triglyceride level over 110 mg/dl and the presence of chylomicrons indicate a chylous effusion. The appearance is generally milky but can be serous.
The main cause for chylothorax is rupture of the thoracic duct, most frequently as a result of trauma or malignancy (such as lymphoma).
Cell count and differential
The number of white blood cells can give an indication of infection. The specific subtypes can also give clues as to the type on infection. The amount of red blood cells are an obvious sign of bleeding.
Cultures and stains
If the effusion is caused by infection, microbiological culture may yield the infectious organism responsible for the infection, sometimes before other cultures (e.g. blood cultures and sputum cultures) become positive. A Gram stain may give a rough indication of the causative organism. A Ziehl-Neelsen stain may identify tuberculosis or other mycobacterial diseases.
Cytology
Cytology is an important tool in identifying effusions due to malignancy. The most common causes for pleural fluid are lung cancer, metastasis from elsewhere and mesothelioma. The latter often presents with an effusion. Normal cytology results do not reliably rule out malignancy, but make the diagnosis more unlikely.



Abdominal tap
Alternative Names: Peritoneal tap; Paracentesis
An abdominal tap is a procedure used to remove fluid from the abdomen.
How the Test is Performed
This test may be done in an office setting, treatment room, or hospital.
The puncture site will be cleaned and shaved, if necessary. You then receive a local numbing medicine. The tap needle is inserted 1 - 2 inches into the abdomen. Sometimes a small cut is made to help insert the needle. The fluid is pulled out into a syringe.
The needle is removed. A dressing is placed on the puncture site. If a cut was made, one or two stitches may be used to close it.
There are two kinds of abdominal taps:
• Diagnostic tap -- a small amount of fluid is taken and sent to the laboratory for testing
• Large volume tap -- several liters may be removed to relieve abdominal pain and fluid buildup
How to Prepare for the Test
Let your health care provider know if you:
• Have any allergies to medications or numbing medicine
• Are taking any medications (including herbal remedies)
• Have any bleeding problems
• Might be pregnant
Infants and children:
The preparation you can provide for this test depends on your child's age, previous experience, and level of trust. For general information regarding how you can prepare your child, see the following topics:
• Infant test/procedure preparation (birth - 1 year)
• Toddler test/procedure preparation (1 - 3 years)
• Preschooler test/procedure preparation (3 - 6 years)
• School age test/procedure preparation (6 - 12 years)
• Adolescent test/procedure preparation (12 - 18 years)
How the Test Will Feel
You may feel a stinging sensation from the numbing medicine, or pressure as the needle is inserted.
If a large amount of fluid is taken out, you may feel dizzy or light-headed. Tell the health care provider if you feel dizzy.
Why the Test is Performed
Normally, the abdomen contains only a small amount of fluid. In certain conditions, large amounts of fluid can build up in the abdomen.
An abdominal tap may be done to diagnose the cause of fluid buildup. It may also be done to diagnose infected abdominal fluid, or to remove a large amount of fluid to reduce abdominal pain.
Normal Results
Normally, there should be little or no fluid in the abdomen.
What Abnormal Results Mean
An examination of abdominal fluid may show:
• Appendicitis
• Cirrhosis of the liver
• Damaged bowel
• Heart disease
• Infection
• Kidney disease
• Pancreatic disease
• Tumor (cancerous or noncancerous)
Risks
There is a slight chance of the needle puncturing the bowel, bladder, or a blood vessel in the abdomen. If a large quantity of fluid is removed, there is a slight risk of lowered blood pressure and kidney failure. There is also a slight chance of infection.
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Bone marrow examination
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A Wright's stained bone marrow aspirate smear from a patient with leukemia.


Bone marrow examination refers to the pathologic analysis of samples of bone marrow obtained by bone marrow biopsy (often called a trephine biopsy) and bone marrow aspiration. Bone marrow examination is used in the diagnosis of a number of conditions, including leukemia, multiple myeloma, anemia, and pancytopenia. The bone marrow produces the cellular elements of the blood, including platelets, red blood cells and white blood cells. While much information can be gleaned by testing the blood itself (drawn from a vein by phlebotomy), it is sometimes necessary to examine the source of the blood cells in the bone marrow to obtain more information on hematopoiesis; this is the role of bone marrow aspiration and biopsy.
Components of the procedure

A bone marrow harvest.


A volunteer donating bone marrow for scientific research.
Bone marrow samples can be obtained by aspiration and trephine biopsy. Sometimes, a bone marrow examination will include both an aspirate and a biopsy. The aspirate yields semi-liquid bone marrow, which can be examined by a pathologist under a light microscope as well as analyzed by flow cytometry, chromosome analysis, or polymerase chain reaction (PCR). Frequently, a trephine biopsy is also obtained, which yields a narrow, cylindrically shaped solid piece of bone marrow, 2mm wide and 2 cm long (60 μL), which is examined microscopically (sometimes with the aid of immunohistochemistry) for cellularity and infiltrative processes. An aspiration, using a 20 mL syringe, yields approximately 300 μL of bone marrow.[1] A volume greater than 300 μL is not recommended, since it may dilute the sample with peripheral blood.[1]
Comparison
Aspiration Biopsy
Advantages • Fast
• Gives relative quantity of different cell types
• Gives material to further study, e.g. molecular genetics and flow cytometry
• Gives cell and stroma constitution
• Represents all cells
• Explains cause of "dry tap" (aspiration gives no blood cells)
Drawbacks Doesn't represent all cells Slow processing
Aspiration doesn't always represent all cells since, as some such as lymphoma stick to the trabecula, and would thus be missed by a simple aspiration.
Site of procedure
Bone marrow aspiration and trephine biopsy are usually performed on the back of the hipbone, or posterior iliac crest. However, an aspirate can also be obtained from the sternum (breastbone). A trephine biopsy should never be performed on the sternum, due to the risk of injury to blood vessels, lungs or the heart.
How the test is performed

A needle used for bone marrow aspiration, with removable stylet.
A bone marrow biopsy may be done in a health care provider's office or in a hospital. Informed consent for the procedure is typically required. The patient is asked to lie on his or her abdomen (prone position) or on his/her side (lateral decubitus position). The skin is cleansed, and a local anesthetic such as lidocaine is injected to numb the area. Patients may also be pretreated with analgesics and/or anti-anxiety medications, although this is not a routine practice.
Typically, the aspirate is performed first. An aspirate needle is inserted through the skin until it abuts the bone. Then, with a twisting motion, the needle is advanced through the bony cortex (the hard outer layer of the bone) and into the marrow cavity. Once the needle is in the marrow cavity, a syringe is attached and used to aspirate ("suck out") liquid bone marrow. A twisting motion is performed during the aspiration to avoid excess content of blood in the sample, which might be the case if an excessively large sample from one single point is taken.
Subsequently, the biopsy is performed if indicated. A different, larger trephine needle is inserted and anchored in the bony cortex. The needle is then advanced with a twisting motion and rotated to obtain a solid piece of bone marrow. This piece is then removed along with the needle. The entire procedure, once preparation is complete, typically takes 10–15 minutes.
If several samples are taken, the needle is removed between the samples to avoid blood coagulation.
After the procedure
After the procedure is complete, the patient is typically asked to lie flat for 5–10 minutes to provide pressure over the procedure site. After that, assuming no bleeding is observed, the patient can get up and go about their normal activities. Paracetamol (acetaminophen) or other simple analgesics can be used to ease soreness, which is common for 2–3 days after the procedure. Any worsening pain, redness, fever, bleeding or swelling may suggest a complication. Patients are also advised to avoid washing the procedure site for at least 24 hours after the procedure is completed.
Contraindications
There are few contraindications to bone marrow examination. The only absolute reason to avoid performing a bone marrow examination is the presence of a severe bleeding disorder which may lead to serious bleeding after the procedure. If there is a skin or soft tissue infection over the hip, a different site should be chosen for bone marrow examination. Bone marrow aspiration and biopsy can be safely performed even in the setting of extreme thrombocytopenia (low platelet count).
Complications
While mild soreness lasting 12–24 hours is common after a bone marrow examination, serious complications are extremely rare. In a large review, an estimated 55,000 bone marrow examinations were performed, with 26 serious adverse events (0.05%), including one fatality. The same author collected data on over 19,000 bone marrow examinations performed in the United Kingdom in 2003, and found 16 adverse events (0.08% of total procedures), the most common of which was bleeding. In this report, complications, while rare, were serious in individual cases.








Tracheotomy




Completed tracheotomy:
1 - Vocal cords
2 - Thyroid cartilage
3 - Cricoid cartilage
4 - Tracheal cartilages
5 - Balloon cuff

Tracheotomy and tracheostomy are surgical procedures on the neck to open a direct airway through an incision in the trachea (the windpipe). They are performed by emergency physicians, and surgeons. Both surgical and percutaneous techniques are now widely used.
While tracheostomy may have possibly been portrayed on ancient Egyptian tablets,[1] the first correct description of the tracheotomy operation for patients who are suffocating was described by Ibn Zuhr in the 12th century,[2] and the currently used surgical tracheostomy technique was described in 1909 by Dr. Chevalier Jackson of Pittsburgh, Pennsylvania.
Terminology
Tracheotomy, from the Greek root tom- meaning "to cut," refers to the procedure of cutting into the trachea and is an emergency procedure.[3]
A tracheostomy, from the root stom- meaning "mouth," refers to the making of a semi-permanent or permanent opening, and to the opening itself.
Some sources offer different definitions of the above terms. Part of the ambiguity is due to the uncertainty of the intended permanence of the stoma at the time it is created.[4]
Uses of tracheotomy
The conditions in which a tracheotomy may be used are:
• Acute setting - maxillofacial injuries, large tumors of the head and neck, congenital tumors, e.g. branchial cyst, acute inflammation of head and neck, and
• Chronic / elective setting - when there is need for long term mechanical ventilation and tracheal toilet, e.g. comatose patients, surgery to the head and neck.
In emergency settings, in the context of failed endotracheal intubation or where intubation is contraindicated, cricothyroidotomy or mini-tracheostomy may be performed in preference to a tracheostomy.
Tracheotomy procedure
1. Curvilinear skin incision along relaxed skin tension lines (RSTL) between sternal notch and cricoid cartilage.
2. Midline vertical incision dividing strap muscles.
3. Division of thyroid isthmus between ligatures.
4. Elevation of cricoid with cricoid hook.
5. Placement of tracheal incision. An inferior based flap, or Björk flap, (through second and third tracheal rings) is commonly used. The flap is then sutured to the inferior skin margin. Alternatives include a vertical tracheal incision (pediatric) or excision of an ellipse of anterior tracheal wall.
6. Insert tracheostomy tube (with concomitant withdrawal of endotracheal tube), inflate cuff, secure with tape around neck or stay sutures.
7. Connect ventilator tubing.
It is also possible to make a simple vertical incision between tracheal rings (typically 2nd and 3rd) for the incision. Rear end flaps may produce more intratracheal granulation tissue at the site of the incisions, making it less favorable to some surgeons.
Percutaneous tracheotomy procedure
1. Curvilinear skin incision along relaxed skin tension lines between sternal notch and cricoid cartilage.
2. Midline blunt dissection down to the trachea (optional depending on technique).
3. Insertion of 14-gauge plastic cannula and needle with fluid filled syringe attached into trachea. Aspiration of air confirms correct placement of the tip in the trachea.
4. Removal of needle leaving cannula in place.
5. Insertion of soft tipped guide wire into trachea through cannula.
6. Removal of cannula leaving guide wire in place.
7. Tracheal dilatation is now undertaken - different techniques do this in different ways.
1. Ciaglia - the sequential insertion and removal of a series (usually 4-5) of increasing larger dilators over the wire into the trachea.
2. Griggs - insertion of a specially designed pair of guide-wire forceps along the wire into the trachea and then are opened to complete the dilation in one step.
3. Rhino - insertion of a single large tapered dilator over a plastic guidewire reinforcement.
4. Frova Percutwist - insertion of a specially designed screw of increasing diameter which rotates to create the dilatation.
8. Insert tracheostomy tube (with concomitant withdrawal of endotracheal tube), inflate cuff, secure with tape around neck or stay sutures.
9. Connect ventilator tubing.
Risks
During the procedure, there is a risk of damaging the recurrent laryngeal nerves. These nerves control the vocal cords. If one of the nerves is damaged a patient will probably have a problem with his/her voice; if both of the nerves are damaged, the patient will lose his/her speech. This risk of nerve damage is the reason emergency tracheotomies are performed higher up, in the larynx and why tracheotomies have to be done in hospital under anesthetic. Professor Stephen Hawking lost his speech due to a tracheotomy after contracting pneumonia.
Moreover, if the recurrent laryngeal nerve is damaged, the patient will have trouble controlling the flow of air through the rima glottidis, thus ultimately leading to inhibited breathing or suffocation.