Tourniquet Use And Care

Preoperative Nursing Assessment Assembling Equipment and Supplies Calibrating and Testing the Equipment Determining Appropriate Cuff Pressure Limb Occlusion Pressure (LOP) Applying the Tourniquet Intraoperative Monitoring Deflating the Tourniquet Bilateral Tourniquets Documenting Tourniquet Use Intravenous Regional Anesthesia (IVRA) Care and Handling of Pneumatic Tourniquet Cuffs Preventive Maintenance and Storage Troubleshooting

Pneumatic tourniquet setup, use, and care and handling will be discussed in this section. Patient safety is the primary concern when working with a pneumatic tourniquet. Take the time to become thoroughly familiar with the particular tourniquet used in your facility.

Preoperative Nursing Assessment

Applying a pneumatic tourniquet and monitoring its use cannot be taken lightly. Ideally, the preoperative assessment is conducted the day before surgery is scheduled.

During the preoperative assessment, review the patient's physical status and medical history. For example:

• Does the patient have allergies (e.g., to prep solution containing iodine, to adhesive tape, or to drugs)?
• What medication(s) is the patient currently taking (e.g., steroids)?
• Does the patient have any preexisting disease that could complicate tourniquet use (e.g., arterial calcification, abnormal clotting time, diabetes, sickle cell trait, tumor, infection, or previous vascular surgery in the involved limb, or hypertension)?

Also during the patient assessment, measure the operative limb for selection of the proper size tourniquet cuff. Record the patient's blood pressure.

Assembling Equipment and Supplies

Efficiency in the operating room demands that all of the necessary equipment and supplies be assembled before the patient arrives in the room. For procedures that will require the use of a pneumatic tourniquet, the following equipment and supplies are necessary:

• Mounting. Some types of tourniquets are mounted on IV poles; others are mounted on portable stands or are placed on a table top.
• Tourniquet instrument. Modern electronic tourniquet instruments have a power cord that must be plugged into a properly grounded power source. The more sophisticated instruments have a backup battery which charges automatically when the unit is plugged in, and therefore the unit should be plugged in whenever possible. Note that some instruments do not have a backup battery and therefore must be plugged in at all times during use.

Some instruments require a connection to hospital pressurized gas supply. Ensure that the source is of the appropriate type and pressure as specified by the tourniquet manufacturer. Other types of tourniquet systems use a disposable pressurized canister. Ensure that the canister is not empty or depressurized and ensure that a spare, new canister is readily available.

• Manufacturer's guides. Keep an operating manual readily available and attach a troubleshooting guide to every tourniquet unit.
• Connecting tubing. Virtually all systems have a hose and connector assembly (positive - locking or Luer) for attaching the cuff to the tourniquet instrument. Ensure that the connectors on the cuff and instrument hose(s) are compatible. If a Dual Port system is being used, ensure that the cuffs are also dual port; similarly for single port systems ensure that the cuffs have a single port. Do not use adapters other than those that may be provided by the instrument manufacturer for connecting the cuff to the instrument.

For systems requiring a hospital pressurized gas supply, another hose attaches the tourniquet to the external pressure source. Ensure that this hose has appropriate connectors and sufficient length.

• Tourniquet cuff. Be sure to select the appropriate cuff style, width, and length as outlined in Section 2.
• Limb Protection. If limb protection is to be used between the cuff and the limb, select the appropriate limb protection material for the selected cuff. It has been reported that the patient’s skin is most effectively protected from wrinkling and pinching under the cuff when a stretched, two - layer tubular stockinette limb protection sleeve matching the size range of the selected cuff is used. Some manufacturers supply a limb protection sleeve with the cuff or supply the sleeve separately with a colored trim matching the appropriate cuff. It is important to ensure that the sleeve matches the cuff selected. If a matching sleeve is not available for the selected cuff, use two layers of tubular stockinette, sized such that it is stretched when applied to the limb at the cuff location and such that the compression applied by the stockinette is less than venous pressure and less than the pressure of a snugly applied cuff. The tubular material should be longer than the width of the cuff, so that the excess length extending beyond the distal edge of the cuff can be folded back over the cuff.

Do not use cotton cast padding, sheet padding, Webril, or any material that may shed loose fibers; lint from these materials can become embedded in the hook and loop cuff fasteners and reduce their effectiveness, possibly leading to an unexpected release of the cuff during the procedure.

• Drape. The size of the drape depends on the limb. It is used to protect the skin from chemical burns and to keep the tourniquet cuff clean. In particular the drape chosen must prevent fluids from collecting between the patient’s skin and the cuff, which can cause skin injury.
• Measuring tape. Use a nonstretch measuring tape to obtain limb circumference. Preferably, the tape should measure both inches and centimeters so the measurement can be compared to tourniquet cuff sizes in either unit.
• Pressure display testing equipment. A calibration kit is available from many manufacturers; a mercury manometer adapted for the testing of the tourniquet display may also be used.
• Elastic bandage. A tensor (e.g. Ace Wrap) or other elastic bandage should be available for exsanguination; in some cases, gravity exsanguination alone will be sufficient and the bandage will not be used.
• Gas canister or tank. If required, ensure that appropriate canisters are sufficiently full and readily available.

Calibrating and Testing the Equipment

It is important to test the pneumatic tourniquet and inspect all of the other components before every patient use. Patient safety demands that all tourniquet parts be functioning properly before the procedure.

Calibrating the Pressure Display

Some pneumatic tourniquets, particularly older non-electronic types, can be subject to large and dangerous discrepancies between the pressure indicated on the display and that exerted by the cuff bladder. Such discrepancies can result in over pressurization or under pressurization of the cuff and underlying soft tissue. The perioperative nurse can minimize potentially hazardous pressure variations by learning how to perform the manufacturer’s recommended calibration tests. Some manufacturers of older, non - electronic tourniquets recommend that calibration be checked before each patient use.

As an accessory, most manufacturers make available a calibration kit with a gauge specifically designed for calibrating the pressure display. If a calibration kit is not provided, a mercury manometer can be used. For a preoperative calibration check, a T - shaped connector can be fitted between the pneumatic tourniquet instrument and the cuff. A manometer is then attached to the T connector. When the cuff is inflated, the pressure display should equal that of the mercury manometer. The display should also be checked for pressure changes (drift) by ensuring that the pressures remain equal over several minutes. If a substantial difference or drift is observed, the tourniquet instrument should not be used and should be sent for repair.

Most modern electronic tourniquet instruments have a self - test mode that is activated when the power switch is turned on. The self - test rapidly verifies all alarm systems and the pressure accuracy of the display. A manual calibration check is normally unnecessary for these units, and if required is performed by appropriately trained biomedical engineering or technologist personnel.

If either a manual calibration test or the computerized self - test indicates that the tourniquet display is in error, do not use the unit. Immediately remove the equipment from service and send it to biomedical engineering for repair.

Testing Other Parts

Before each use, inspect the tourniquet instrument and mounting, connecting tubing, gas source (if used), and cuff. Make sure that all connections are in good condition and are securely fastened according to the manufacturer's written instructions. To guard against accidental deflation, connect the cuff to a tourniquet instrument, wrap the cuff onto itself, secure all fasteners, and inflate the cuff. Check to make sure that there are no leaks in the cuff, tubing, or connectors. If gas tanks or canisters are used, check the gas level before the procedure begins.

A reusable tourniquet cuff is subject to wear and deteriorates with use. When inspecting the cuff before each use, give special attention to the following questions:

• Is there any physical damage (rips, tears, holes, etc.) to the cuff? If the cuff is not completely intact, it may leak or burst, causing an unexpected loss of pressure.
• Is (are) the connector(s) bent, broken or worn?
• If there is a ribbon tie, is it torn or the ribbon stitching broken?
• Is the contact closure torn or is any of the strap stitching broken?
• After cleaning, is more than 25% of the contact closure embedded with fibers that cannot be removed?
• Is there any other physical change or damage to the cuff that would compromise the cuff's ability to maintain occlusion during the surgical procedure?
• Have permanent kinks or ridges formed in the stiff structure inside the cuff (palpable through the cuff outer material), particularly along the inner surface facing the patient’s limb?

If any of the above conditions are present, do not use that particular cuff. Use of a damaged cuff could result in one or more of the following unwanted events:

• Loss of cuff pressure.
• Release of the cuff from around the patient's limb.
• Movement of the cuff on the patient's limb.
• Excessive leakage of cuff pressure.
• Pinching of tissue under the cuff leading to injury.

Some of these failures could cause catastrophic injury, including death, to the patient by releasing blood into the surgical site or releasing a bolus of anesthetic into other parts of the body.

Determining Appropriate Cuff Pressure

The physician is responsible for determining the appropriate tourniquet cuff pressure. The objective is to maintain a cuff pressure that is high enough to completely suppress arterial circulation and produce a bloodless field, yet low enough to minimize the risk of neuromuscular injury. Lower pressures have also been shown to reduce postoperative pain associated with tourniquet use. Calculation of this "minimum effective pressure" is not always straightforward. The surgeon must take into account the following factors:

• Blood pressure.
• Cuff design, fit, and snugness of application.
• Limb circumference.
• State of the tissue.
• Vascular status.

Blood Pressure

The patient's systolic blood pressure is an important criterion for determining the minimum amount of cuff pressure required to suppress arterial circulation. It is important to consider:

• The patient's systolic blood pressure measured immediately prior to the induction of anesthesia.
• The maximum anticipated rise in systolic pressure during the surgical procedure (due to anesthesia or physiological difficulties).
• Potential for movement of the limb during surgery, which can cause transient drops in cuff pressure. The set pressure must be high enough to prevent blood seepage during such movement.
• The presence of hypertension, which demands a higher tourniquet cuff pressure.

Cuff Design, Fit, and Snugness of Application

Tourniquet cuff design also affects the minimum cuff pressure needed to occlude arterial flow. With dual bladder cuffs, a higher pressure is often required to achieve occlusion and ensure a bloodless operative field because the individual bladders are narrower. It has been reported that curved and wider tourniquet cuffs occlude blood flow at a lower inflation pressure than straight or narrow cuffs. If a cylindrical cuff is used on a significantly tapered limb, the effective width of the bladder is reduced due to the loose distal portion of the cuff and the required pressure may be higher than normal. Similarly, if a cuff of any design is applied too loosely or applied over a thick layer of loose padding, higher pressures may be required to occlude the limb.

Limb Circumference

The circumference of the limb at the site of cuff application also affects the cuff pressure required to suppress circulation. Circumference is an external indicator of the depth of soft tissue through which tourniquet cuff pressure must be exerted. Research has demonstrated that soft tissue pressure is lower than tourniquet cuff pressure, and decreases with the depth of the tissue. For a slender, thin limb, the cuff pressure indicated on the pressure display is very close to the pressure actually exerted on the deep artery. However, for limbs with a large mass of fatty or muscular subcutaneous tissue, a higher tourniquet cuff pressure is required to ensure sufficient pressure to occlude arterial circulation.

Similarly, the lower extremities have a higher tissue mass than the upper extremities; therefore, a higher tourniquet pressure is necessary to transmit sufficient pressure through the tissue to occlude the deep vessels.

State of the Tissue

The state of the tissue (its flaccidity or tenseness) at the site of cuff application also has an effect on the pressure exerted. Folds and puckers in underlying flaccid tissue can cause skin injury and uneven pressure on vessels. Tense, strong muscle resists pressure more readily than soft muscle.

Vascular Status

Usually, the presence of atherosclerotic vascular disease or similar diseases that occlude the artery demands a higher tourniquet cuff pressure. Atherosclerotic vascular disease is a common condition in older patients. It makes arteries resistant to tourniquet - exerted pressure.

Limb Occlusion Pressure and optimum cuff pressure setting

Clinical and laboratory studies have shown that the minimum effective pressure cannot be reliably predicted using a standard pressure or a simple formula based on the factors listed above. For each individual limb, cuff, and cuff application there is a unique cuff pressure required to occlude arterial flow in the limb, known as the Limb Occlusion Pressure (LOP). These studies have demonstrated that the best way to optimize cuff pressure is to apply the cuff and, after induction of anesthesia and prior to cuff inflation, measure the LOP with the applied cuff. Cuff pressure is then set to the LOP plus a predetermined safety margin which allows for changing conditions during the procedure.

To measure the LOP, use the following procedure:

Select the cuff to be used in the procedure Apply the cuff over the appropriate limb protection material Using a Doppler stethoscope, locate an arterial pulse distal to the cuff. Normally the radial artery is used on the arm, and the posterior tibial artery is used in the leg. The dorsalis pedis artery may also be used for the leg (see Figure 11). Slowly increase cuff pressure until the arterial pulse stops and remains stopped for several heartbeats Note the cuff pressure: This is the LOP Deflate the cuff and confirm that the distal pulse resumes Prior to cuff inflation, adjust the cuff pressure setting to the noted LOP plus a safety margin.

Figure 11. A manual Limb Occlusion Pressure (LOP) measurement with a Doppler stethoscope and lower leg cuff

A safety margin of the LOP plus 40 - 100 mmHg have been suggested in the literature, and typically the margin required is lower for lower LOP levels and higher for higher LOP. A higher margin may be selected if a considerable amount of manipulation of the limb and/or large blood pressure rises are expected to occur during the procedure. One cuff pressure setting method that has been used successfully in clinical studies is LOP + 40 mmHg for LOP levels less than 130 mmHg, LOP + 60 mmHg for LOP levels between 131 - 190 mmHg, and LOP + 80 mmHg for LOP levels greater than 190 mmHg.

LOP measurement should be made when the blood pressure is approximately stabilized to the level expected during surgery. Depending on the anesthetic technique, the LOP measurement may therefore occur before or after induction of anesthetic. Blood pressure at the time of LOP measurement should be noted.

Applying the Tourniquet

After the patient is brought into the OR, apply the tourniquet at the proper location on the limb, for an appropriate period of time, and within the appropriate pressure range. Take the following steps:

If the patient is to be awake during the procedure, explain any tourniquet alarm sounds that may be heard during the procedure. This is particularly applicable for microprocessor - controlled tourniquet systems. If general anesthesia is planned, record the patient's blood pressure prior to induction. The cuff location should be selected such that as much tissue as possible lies between the cuff and any nerves or vascular structures that could be subject to damage: Place an arm cuff midway between the shoulder and elbow. Place a thigh cuff on the proximal third of the thigh. Position a lower leg cuff so the distal edge of the cuff is at least 2 inches (5 cm) proximal to the ankle malleoli and the proximal edge is at least 2 inches distal to the head of the fibula. Normally the proximal edge of the cuff will lie in the mid range of the calf near the point of maximum calf circumference. Apply the appropriate limb protection material to the limb in the area selected for the cuff, unless the selected cuff is specifically recommended to be used without limb protection. Make sure that the limb protection material (if used) and the skin under the cuff are wrinkle - free. Position the cuff so that the hose connections are accessible under the drapes and the tubing will not be kinked or in the surgical field when the limb is positioned for surgery, then smoothly wrap the cuff around the limb and pull snug by grasping the tie ribbon with one hand and pulling the strap end of the cuff snug with the other hand. Pull in a direction roughly along (tangent to) the circumference of the limb, not away from the limb. Press the hook and loop (VelcroTM type) fasteners on the cuff strap and outer surface together firmly along their entire length. Make sure that the cuff fits snugly. The deflated cuff should not be tight enough to impede venous return of blood from the extremity. In general a snug fit allows two fingers under the cuff. If only one finger fits under the cuff, the cuff is too tight; if three fingers fit, it is too loose. Tie the ribbon to prevent strap or cuff movement during the procedure if the limb is manipulated. Connect the cuff to the tourniquet instrument, using the hose assembly. For procedures that require a dual - bladder cuff or two single - bladder cuffs, use two hose assemblies and make sure all OR personnel who may be operating the tourniquet clearly understand which bladder or cuff is connected to the first and second cuff channels on the tourniquet instrument. If a dual cuff control valve is being used with a single channel tourniquet instrument, make sure personnel are fully familiar with the valve operation. Ensure that all connections are securely fastened. If a limb protection sleeve or stockinette material is being used, fold the portion extending beyond the distal cuff edge back over the cuff (see Figure 12). This may help prevent the cuff from sliding distally off the limb protection material. To prevent antimicrobial skin prep solutions and other fluids from running under the cuff, cover the tourniquet cuff with a plastic drape, with the drape's adhesive edge placed over the distal edge of the cuff. If your tourniquet system has an elapsed time display and alarm function, set the elapsed time to zero and set the time alarm to the desired period, normally 60 to 90 minutes depending on the surgical procedure. If possible, measure the Limb Occlusion Pressure (LOP) using the applied tourniquet cuff. As outlined above, the LOP reading may occur before or after induction of anesthetic, depending on the anesthetic technique. The physician may use the LOP plus a safety margin to determine the desired cuff pressure. Exsanguinate the limb. Careful and complete exsanguination reportedly prolongs pain - free tourniquet time; however, partial exsanguination may be desirable in certain cases where residual blood flow will aid in visualization and identification of vascular structures. Elevate the limb for a minimum of 2 minutes and, if the surgeon indicates, wrap an elastic bandage around the limb beginning at the distal end and ending about 1 inch (2.5 cm) distal to the cuff (to prevent the cuff from slipping distally and to maintain cuff effectiveness). Do not use an elastic bandage for exsanguination in cases where bacteria, exotoxins, or malignant cells could be spread to the general circulation, or where it could dislodge thrombi that may have formed in the vessels. Instead, accomplish exsanguination by elevating the limb for 3 - 5 minutes.

Rapidly inflate the tourniquet to the set pressure specified by the physician. (Rapid inflation of the cuff occludes arteries and veins simultaneously, avoiding return of blood into the limb, thus preventing the filling of superficial veins before occlusion of the arterial blood flow.) Make sure that the pressure display is clearly visible. IMPORTANT: Record the time of inflation, the tourniquet pressure, and the patient's blood pressure at time of inflation. If used, remove the bandage used for exsanguination. Before the surgical procedure begins, verify full occlusion by arterial palpation and/or auscultation. This ensures that the pressure setting and cuff application for that patient is correct and successful. Prepare the skin according to standard procedure and drape the operative site in preparation for the incision. In the event that arterial blood flow is observed past the tourniquet cuff, the surgeon may request that tourniquet pressure be increased. One commonly used method is to increase pressure in 25 mmHg increments until blood flow stops.

Figure 12.Cuff with limb protection sleeve folded back over distal edge

Intraoperative Monitoring

Intraoperative monitoring of tourniquet safety parameters reduces the risk of complications. During the procedure, it is important to monitor the patient's blood pressure, tourniquet pressure, and tourniquet time.

Blood Pressure

Monitor the patient's blood pressure for fluctuations and relate this information to the surgeon.

Tourniquet Pressure

Adjust the tourniquet pressure at the physician's request. Monitor the cuff pressure display during surgery and immediately report any changes to the surgeon. Any sudden loss of cuff pressure intraoperatively is a cause for serious concern. If the tourniquet cuff fails for any reason, deflate it fully, and re - exsanguinate the limb before re - inflation. Re - inflation over blood - filled vasculature may lead to intravascular thrombosis.

Tourniquet Time

It is the physician's responsibility to determine when the tourniquet is to be inflated, at what pressure, for how long, and at what point in the procedure the tourniquet should be released. It is customary to prominently note the time of cuff inflation and to notify the physician after a certain time has elapsed and at pre - established intervals thereafter. Modern electronic tourniquet systems have an elapsed time display and an alarm which can be set to sound after a predetermined amount of tourniquet inflation time.

There is no clearcut rule as to how long a tourniquet may be inflated safely, although various investigators have addressed effects of ischemia on muscle and nerve to define a relatively "safe" period of tourniquet hemostasis. In practice, safe tourniquet inflation time depends greatly on the patient's anatomy, age, physical status, and the vascular supply to the extremity. Unless instructed otherwise, report to the surgeon when 60 minutes of tourniquet time has elapsed. There is general agreement that for reasonably healthy adults, 90 minutes should not be exceeded without releasing the tourniquet for a short time.

Releasing the tourniquet allows for removal of metabolic waste products from the limb and nourishment of the tissue with oxygenated blood. During this time, elevate the limb 60 degrees to encourage venous return and apply steady pressure to the incision with a sterile dressing. Tissue aeration periods should last at least 10 and preferably 15 minutes the first time and 15 - 20 minutes subsequently. To proceed with the surgery, re - exsanguinate the limb before reinflating the cuff. Take care during this procedure to maintain the sterility of the operative field. No known safe limit to the number of aeration intervals during prolonged tourniquet time has been established.

Deflating the Tourniquet

At the surgeon’s request, deflate the tourniquet cuff by taking the following steps:

1. Apply pressure dressings over the incision to protect the wound from blood resurgence. Ideally, the final bandage is applied and pressure is exerted over the incision prior to tourniquet cuff deflation, to prevent blood resurgence. Sometimes, however, the tourniquet is deflated before incisional closure in order to better identify and control bleeding.
2. If necessary to prevent blood resurgence, elevate the limb 45 - 60 degrees. Transient pain upon tourniquet release can also be lessened by elevating the limb.
3. Deflate the tourniquet cuff rapidly to establish immediate venous return and prevent engorgement.
4. Record the time of deflation.
5. Immediately remove the deflated cuff and any underlying limb protection following cuff deflation. Even the slightest impedance of venous return by the deflated cuff or padding may lead to congestion and pooling of blood in the operative field.
6. Record the time of cuff removal.
7. Check the circulation of the limb. Note the return of color to the limb and any abnormalities. If full color does not return within 3 - 4 minutes after release, place the limb slightly below body level.
8. Inspect the cuff site and note any signs of soft tissue damage.

Bilateral Tourniquets

Additional care must be taken in bilateral procedures involving tourniquet control on two limbs, as the risk of complications and the effects of tourniquet use may be increased. Exsanguinating and inflating the cuff on both limbs in rapid succession may cause a more pronounced blood pressure rise due to the sudden decrease in effective circulation system volume. In studies, clotting time decreases and more pronounced blood pressure decreases were found after second cuff deflation. In children, body temperature rise during surgery has been shown to be significantly greater with bilateral tourniquets compared to unilateral, and more pronounced pH drops (greater lactate increases) were found when bilateral cuffs were deflated simultaneously. If possible, bilateral tourniquet deflations should be staggered by 30 to 45 minutes.

It is particularly important in the bilateral case to confirm that the first tourniquet cuff has been completely deflated (and the cuff and limb protection removed if possible) and that circulation in the first limb has been restored, because any related problems could go unnoticed throughout the second limb procedure.

Documenting Tourniquet Use

Documentation of tourniquet use is always a nursing responsibility. Documentation provides information for continuity of care, retrospective review, and research. Careful records become particularly important if a patient sustains an injury and a lawsuit is filed. Record only observable facts, rather than any judgmental opinion.

Information is usually entered on a special record. Such records include, at minimum, the following items:

• Identification/serial number and model of the tourniquet.
• Identification of the person who applied the cuff.
• Location of the cuff.
• Times of inflation and deflation of the tourniquet.
• Length of tissue aeration periods, if applicable.
• Original tourniquet pressure.
• Initial systolic blood pressure.
• Subsequent systolic blood pressures.
• The fact that the surgeon was informed of elapsed tourniquet time and any alterations in systolic blood pressure.
• Skin and tissue integrity under the cuff before use of the pneumatic tourniquet and when the patient is sent to postanesthesia recovery.
• Any abnormal or adverse occurrences.

If an abnormal event occurs, note the time any symptoms began and ended. Enter adverse reactions on the appropriate record, as dictated by institutional policy. If a malfunction in the pneumatic tourniquet causes serious injury, or contributes to the death of a patient or other individual, this information should be reported to the manufacturer and to the U.S. Food and Drug Administration, in accordance with the Safe Medical Devices Act of 1990.

Table 3 provides a checklist that could be used to document pneumatic tourniquet testing and use. The actual testing method and criteria used are established by institutional policy. This checklist is designed to serve as a general guideline only.

Table 3. Checklist for use of pneumatic tourniquet equipment

Intravenous Regional Anesthesia (IVRA)

IMPORTANT: Tourniquet users must be familiar with the inflation - deflation sequence when using a dual - bladder cuff or when using two single - bladder cuffs together for IVRA. If the wrong bladder or cuff is released inadvertently due to user error, it could cause severe injury or death to the patient. In addition, the users must be familiar with operation of the tourniquet instrument and any auxiliary pneumatic valves connected to the cuffs. Some more sophisticated tourniquet systems incorporate safety functions to help reduce the risk of accidental deflation of both cuffs during an IVRA procedure. To further reduce risks, users must be fully aware of which cuff is proximal, which cuff is distal, and the inflation/deflation status of each at all times.

The tourniquet procedure for IVRA is similar to other tourniquet procedures, with the following important differences:

1. When conducting a preoperative assessment prior to IVRA, it is very important to note any allergies to local anesthetics.
2. A dual - bladder tourniquet and extra connective tubing are required.
3. A wider placement site is needed because of the dual - bladder cuff.
4. A higher pressure is generally required because each cuff bladder is narrower.

Tourniquet Application for IVRA

1. The patient will be awake for the procedure; to alleviate any fears related to the procedure, explain the equipment, alarms, or other unfamiliar items.
2. Cannulate a vein in the distal portion of the limb. (An angiocath is preferred to a butterfly needle because it is less likely to be moved out of position during application of the elastic bandage.)
3. Apply limb protection (if used) to the limb.
4. Apply the dual - bladder tourniquet smoothly and snugly, individually fitting each bladder to the shape and circumference of the patient's limb.
5. Connect each bladder of the dual - bladder cuff to the tourniquet instrument. (Consult the tourniquet instrument instruction manual for more information on this connection. If a dual cuff control valve is used between the tourniquet instrument and the cuff ensure that you are familiar with the connection and operation of the valve.
6. Fold the distal portion of the limb protection sleeve back over the distal edge of the cuff. Place the protective plastic drape around the tourniquet and limb.
7. Elevate the limb and wrap with the elastic bandage to exsanguinate the limb.
8. Inflate the proximal bladder to its set - point. (Generally, the proximal bladder is inflated first, but sometimes the distal bladder is the first one inflated in order to complete exsanguination). Limb Occlusion Pressure (LOP) is particularly useful in setting the cuff pressure in IVRA procedures due to the importance of maintaining occlusion and the generally higher pressures required due to the narrow width of each bladder.
9. Remove the elastic bandage.
10. Verify full occlusion by palpation and/or auscultation.

Induction of Anesthesia

After tourniquet placement, the following steps may be taken to induce IVRA. This procedure is presented as a general guideline and may differ in your institution:

1. A predetermined amount of local anesthetic is slowly injected into the cannulated vein via syringe or drip method (usually the responsibility of the anesthesiologist). Care must be exercised not to over distend the vein by rapid infusion.
2. Immediately begin to observe the patient's physiological status for any sign or symptom of a toxic reaction to the local anesthetic. (The presence of an anesthesiologist in this instance does not release the nurse from noting any adverse or toxic reactions to the anesthetic agent.)
3. The angiocath may or may not be removed.
4. The anesthetic agent circulates throughout the veins and venules distal to the tourniquet and perfuses the sensory and motor nerve trunks and endings.
5. In about 3 minutes, the limb should be anesthetized. During this time the limb may be prepped and draped for the surgical procedure.
6. About 20 - 30 minutes following the onset of anesthesia, if the patient feels pain from the cuff, inflate the distal tourniquet over the anesthetized limb and deflate the proximal tourniquet. The patient should feel more comfortable since the tissue under the distal bladder has been anesthetized. NOTE: Tourniquet users must be familiar with the inflation - deflation sequence described below when using a dual - bladder cuff.

Deflating the Tourniquet

NOTE: Tourniquet users must be familiar with the inflation - deflation sequence when using a dual - bladder cuff or using two single - bladder cuffs together. If the wrong bladder or cuff is released accidentally, it could cause severe injury or death to the patient.. Never leave the patient unattended for any reason during intermittent deflation.

1. When IVRA is used, it has been suggested in published literature that the tourniquet remain inflated for a minimum of 20 minutes from the time of injection to ensure that most of the anesthetic agent has been absorbed into the limb tissue. For a procedure requiring only a few minutes, too rapid a release of anesthetic agent can be prevented by quickly deflating and reinflating the cuff several times, or by slowly decreasing the cuff pressure.
2. Upon completion of the procedure, fully deflate the tourniquet bladder, while the surgeon elevates the limb to enhance venous return and exerts pressure over the incision to prevent bleeding and hematoma formation. Deflation to zero pressure each time is important to prevent venous distention, which leads to bleeding and hematoma formation. A short (15 - second) deflation period permits the wash of local anesthesia and anaerobic waste products back into the general circulation in small doses to minimize toxic reactions.
3. Observe the patient's mental status and cardiac monitor carefully, as this is the time when complications are most likely to occur.
4. Reinflate for 30 - 45 seconds to allow nourishment of the tissue with oxygenated blood and diffusion of the anesthetic agent and waste products back into venous circulation.
5. Apply the dressing and move the patient to the recovery area.
6. The anesthetic effect recedes within 15 - 20 minutes, and patients can be safely discharged from the post anesthesia care unit more promptly than when other anesthetic techniques are used.

Care and Handling of Pneumatic Tourniquet Cuffs

Handle tourniquet cuffs carefully. Never puncture the cuff. Handle towel clips used near the cuff with care. Avoid excessive compression of the cuff by a leg holder.

Various types of microorganisms are commonly found on contact closure - covered tourniquets and on Penrose drains. The tourniquet cuff, which is placed near the patient's axilla or groin, may be a source of pathogenic microorganisms. After each use, it is important to decontaminate the tourniquet components, by following the manufacturer’s recommended cleaning procedures. The following cleaning procedure is presented as an example only:

1. If the tourniquet cuff is adequately protected during surgery, hand washing of the cuff and bladder in lukewarm water is the only decontamination procedure indicated. If the bladder and plastic liner are removable, wash them as separate items. Do not immerse the bladder unless the connectors are sealed; if fluid enters the bladder, mildew may form, or subsequent deflation of a wet bladder during use may cause minute droplets of water to be forced back into the tourniquet regulating mechanism. Prevent rapid deterioration, shrinkage, and fading of the cuff fabric by avoiding hot water, harsh detergents, or bleaches.
2. If blood or other body fluid comes in contact with these items, add an enzymatic detergent to the wash water to remove blood components from the fabric and rubber.
3. If necessary, use a hand brush to remove encrusted material.
4. If loose fibers are present in the contact closure straps, it may be possible to remove them using a nonmetallic brush or a comb in a side - to - side manner. If this is not effective the cuff must be replaced. This problem is often caused by using non - woven cast padding type materials under the cuff.
5. Rinse the cuff and bladder thoroughly; detergent residue increases the chances for allergic reactions and may decrease the life of the cuff.
6. Carefully follow manufacturer's instructions for drying. As a rule, air - dry the cuff and bladder flat, at room temperature, in their original shapes. Drip drying over a rack may stretch the cuff over time.
7. Clean the exterior of the cuff hoses using a mild detergent solution, or a disinfectant that is not deleterious to rubber or polyethylene.
8. After each use, decontaminate the exterior of the tourniquet instrument by wiping it with a cloth that has been dampened (not dripping) with a mild detergent.
9. Avoid storing the cuff tightly rolled up to a small diameter as this may cause permanent kinking and ridging of the stiffened inner structure of the cuff. If possible store the cuff rolled loosely to approximately its normal in - use diameter.

Most modern reusable tourniquet cuffs are not recommended for sterilization. Always follow the manufacturer's written instructions regarding the ability to sterilize any cuff. If a sterile cuff is required use a sterile disposable tourniquet cuff. Under no circumstances should a tourniquet cuff be steam sterilized unless specifically recommended by the manufacturer. Any exposure to steam sterilization will render most cuffs permanently unusable.

Preventive Maintenance and Storage

A comprehensive pneumatic tourniquet management program helps identify equipment problems that may adversely affect patient safety. Regular maintenance checks by the biomedical engineering department should include calibration of the pressure regulator and display with a calibrated pressure standard and regular inspection of the regulator on every mechanical tourniquet. Refer to the tourniquet controller operator's manual for information on the appropriate frequency, method, and criteria for pneumatic tourniquet testing. Document the date of inspection, preventive maintenance performed, and status of all equipment. Review records of equipment failure and preventive maintenance to help identify equipment performance problems or hazards.

It is the nurse's responsibility to calibrate a mechanical tourniquet prior to each patient use. If the pressure indicated by the mercury manometer is different from the set pressure by more than 10%, pull it out of service and send it to biomedical engineering.

Store pneumatic tourniquet components as a unit in an environment that is dust - free, clean, and cool; cover with a reusable or disposable fabric. Along with the equipment, store the manufacturer's guide to troubleshooting and use. Prominently display the manufacturer's name, model number, and serial number. Depending on hospital policy, tagging each tourniquet with the date of its most recent maintenance check may be required. Notation of date of most recent use is valuable for facilitating rotation among stored units.

Tourniquets that use battery power may have additional storage requirements, such as leaving the tourniquet’s electrical power cord plugged into an electrical outlet. Refer to your tourniquet system’s operating manual for specific storage instructions.

Troubleshooting

Table 4 provides sample troubleshooting guidelines. Many of these problems are device - specific, and may not apply to your tourniquet system. This is particularly true for computerized, digital systems. Read the manufacturer's operating manual carefully for troubleshooting guidelines specific to your system.

Table 4. Troubleshooting Guide