Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Clinical Skill Information Sheet Bag Valve Mask (BVM) Ventilation Aim To safely and effectively ventilate patients using a bag-valve-mask Indications When a patient is unable to effectively self-ventilate and is at risk of hypoxia. Background When a patient is unable to breathe for him or herself and/or has inadequate ventilation rate or effort, it is vital that they are ventilated with oxygen to ensure hypoxia is avoided. A paramedic using a bag-valve-mask performs ventilations. The Bag-Valve-Mask (BVM) is a piece of equipment that can either be reusable or disposable. It can be used with a number of different sized masks to ensure an adequate seal for all patients. There are a number of different sized bags to better suit particular patients, such as adults, paediatrics and neonates. The BVM is initially used with a basic airway: an oropharyngeal airway (OPA) but can also be attached to advanced airway adjuncts, such as a laryngeal mask airway (LMA) or endotracheal tube (ETT). The BVM is often operated by one trained operator, but can also be operated by two trained operators, which is the recommended method in all patients especially those who are difficult to ventilate. Bachelor of Paramedic Science Clinical Skill Information Sheet Objective Manage Safety Prepare the patient Rationale Safety is the first priority when managing any patient. Action 1. Use universal precautions. Always wear gloves and goggles when attending to a patient. Ensure the patient has a clear airway and is positioned appropriately to be ventilated. 2. You may also want to consider wearing a facemask and gown. 1. Position yourself behind the head of the patient. You may be kneeling if they are lying on the ground or you may be able to sit/stand behind them if they are on furniture such as a bed, stretcher or recliner chair. Ideally, you want the patient’s head around waist height. The paramedic must be positioned appropriately to ensure that the correct technique is utilised and ventilation is effective. Ensuring equipment is in working order is essential to providing adequate ventilation to a patient. Prepare the equipment 2. Ensure the patient’s airway is clear. (See Basic Airway Management – Information Sheet) 1. Ensure all parts of the BVM are securely attached in the appropriate manner. See relevant manufacturer’s instructions for this. Correct mask selection is essential to ensure an effective seal can be gained and maintained during patient ventilation. The amount of air in the rim of the mask can be adjusted using a syringe to accommodate different face shapes. 2. Select the appropriate sized mask for the patient. This will be determined by the size of the patient’s face. Ensure the mask can encapsulate the patient’s mouth and nose. Bachelor of Paramedic Science Clinical Skill Information Sheet Objective Correct hand positioning (single operator) Rationale The maximum oxygen flow rate is required to ensure adequate inflation of the reservoir bag and appropriate oxygen pressures. Action The maximum flow setting for a particular oxygen cylinder will be 3. Attach the oxygen tubing to the BVM dependent on the flow using the designated port. gauge. Commonly, this is 15 L/min for a C4. Dial the oxygen up to its maximum sized cylinder, and setting. 25L/min for a D-sized cylinder. 5. Ensure the reservoir bag inflates completely before applying assembled unit to patient. Using the “C-E” grip to 1. Position yourself at the head of the hold the patient’s face patient. up and into the mask will ensure that 2. With one hand, use your thumb and occlusion of the airway forefinger to make the shape of the is avoided. letter C. Your remaining three fingers will naturally form the shape of the letter E. Below is an effective C-grip. It is essential to ensure a patent airway at all times so that obstruction to airflow is minimised. There are a number of hand positions that are effective, due to the size of the mask used and the operator’s hands. As long as a good seal around the face and an open airway are maintained, something comfortable and sustainable for you is ideal. 3. Use this grip to hold the back of the facemask firmly. Bachelor of Paramedic Science Clinical Skill Information Sheet Objective Rationale Action 4. Position the top of the mask at the top of the patient’s nose. 5. Simultaneously lower the mask to the patient’s face whilst using your three fingers to pull their face up and into the mask. Ensure your fingers are holding on to the patient’s mandible and not the soft underside of their chin. You will need to continue applying an upwards pressure everytime you ventilate the patient. Although it is often necessary in the prehospital setting for a single operator to ventilate a patient with the BVM due to limitations of resources, it is best practice to use a twohanded technique to hold the mask. This ensures an effective seal is maintained. Correct hand positioning (two operator) 6. Ensure a good seal by listening for air leaks. 1. Position yourself at the head of the patient. 2. Either use a CE grip with both hands to hold the back of the mask, as shown below. OR use a modified CE grip by placing both of your thumbs either side of the back of the mask, as shown below. 3. Position the top of the mask at the top of the patient’s nose. Bachelor of Paramedic Science Clinical Skill Information Sheet Objective Rationale Action 4. Simultaneously lower the mask to the patient’s face whilst using your fingers to pull their face up and into the mask. Ensure your fingers are holding along the patient’s jaw and not the soft underside of their chin. You will need to continue applying an upwards pressure everytime you ventilate the patient. 5. Ensure a good seal by listening for air leaks. It is imperative that the 1. Using your spare hand (or getting correct technique is someone else if you are using the 2utilised as the delicate operator technique) hold the selfairways and lungs can inflating bag and gently and smoothly be damaged if lung squeeze it in one fluid motion until your volumes are exceeded or fingers touch. Ensure this process ventilations are too occurs over about 1 -1.5 seconds. This forceful. will mean the bag has been fully compressed. Some of the BVM’s have pressure relief (blow-off) valves to protect from overzealous ventilation, however these devices should not be relied upon and correct technique should always be the clinician’s main aim. Correct ventilation technique The bag should be easy to squeeze, with minimal effort required. Sometimes the patient’s physiological state will be the cause of the difficulty, e.g. bronchoconstriction. In this instance, extra care must be taken to not over-ventilate the patient and allow for a prolonged expiratory phase. Most adult self-inflating bags come in volumes from 1200-1600mL. They should only need compression of approx.1/3 to achieve adequate ventilation for an adult tidal volume (~500mL). 2. Release your grip completely and allow the bag to self-inflate fully. 3. If you find it very difficult or hard to squeeze the bag, then there may be an obstruction in the airway. Ensure you are performing the correct grip and holding the patient’s face up and into the mask. If this does not solve the problem then check the airway again for obstructions, you may need to use an advanced assessment tool for this, e.g. laryngoscopy. 4. If the bag does not self-inflate after delivering a ventilation ensure that the equipment is attached correctly and that the oxygen is freely flowing through the device at an appropriate rate. Bachelor of Paramedic Science Clinical Skill Information Sheet Objective Correct ventilation rate Measure effectiveness Rationale The rate of ventilation will be dependent on the patient’s condition. In most instances returning the patient to within normal oxygen saturation levels is the aim. Action 1. Cardiac Arrest – follow the resuscitation algorithm dependent on the airway adjunct device in use (i.e. OPA, LMA, ETT). With a basic airway in situ, and a compression: ventilation ratio of 30:2, you should be providing two ventilations about every 18 seconds. A normal healthy person will breathe between 12-20 respirations per minute. 2. Assisted ventilations – when assisting with ventilations using the BVM, you may need to fully ventilate the patient as explained above. In this case, aim to provide one ventilation every 5 seconds. Sometimes the patient may be breathing at a sufficient rate, but the depth is inadequate. In which case you need to squeeze the bag a little to provide extra oxygen with each breath they take. Time it so that you squeeze the bag as they inhale. You will feel that it is relatively easy to push the air into their airways. If you attempt to do it as they are exhaling, you will feel significant resistance and you will hear air escaping through the sides of the mask, or the relief valve. 1. If the patient is apnoeic and you are ventilating by squeezing the bag, watch for rise and fall of the patient’s chest. This will give you a clear indication of whether the oxygen is getting into their lungs. Sometimes it is difficult to see rise and fall of the patient’s chest due to their anatomy. It is important to periodically confirm that air is entering the lungs and not the stomach by having a colleague listen with a stethoscope. The patient’s skin colour and oxygen saturation measurements are also indicators for the effectiveness of the ventilation. 2. Have a colleague use a stethoscope to auscultate the patient’s chest to ensure adequate air entry. Bachelor of Paramedic Science