Pulse and Abnormalities

Pulse

• Pulse is the alternating expansion and recoil of an artery as blood flows through it during the contraction of the left ventricle.
• Pulse can be felt by the finger, not the thumb due to vessels in the thumb.
• Normal adult pulse rate is 60-100 beats per minute.
• Tachycardia is a heart rate over 100 bpm.
• Bradycardia is a heart rate under 60 bpm.
• Common pulse assessment sites include radial (most common), temporal, carotid, brachial, femoral, popliteal, dorsalis pedis, posterior tibial, and apical (5th intercostal space, left midclavicular line).
• Avoid pressing both carotid arteries simultaneously, as this can cause a drop in blood pressure.
• Cardiac and brachial/femoral arteries are used for assessing pulse in shock/cardiac arrest victims, especially in infants.

Abnormal Pulse Volumes

• Water hammer pulse (Corrigan's pulse/collapsing pulse) is a strong throbbing pulse, signifying aortic regurgitation.
• Bounding pulse is a strong throbbing pulse indicating increased cardiac output.
• Bigeminal pulse is an irregular pulse where alternating beats are weaker, often due to weak ventricular contractions.
• Weak wiry/thread pulse indicates decreased stroke volume, possibly from heart failure, heat exhaustion, or shock.
• Paradoxical pulse weakens on inhalation, usually due to heart conditions.
• Pulses alternans are regular, but the strength of the pulse alternates, meaning it is strong one beat and weak the next.

Respiration

• Normal respiration (eupnea) is the act of breathing, taking in oxygen and releasing carbon dioxide.
• Tachypnea/Polypnea is a respiratory rate over 24 breaths per minute.
• Bradypnea is a respiratory rate under 10 breaths per minute.
• Apnea is the cessation of breathing.
• Hyperpnea involves increased breathing depth.
• Orthopnea: breathing only in an upright position.
• Stertorous respiration is noisy breathing from secretions.
• Rales/Rhonchi are rattling sounds caused by mucus in the airways (e.g., bronchitis, pneumonia).
• Wheezing is a high-pitched whistling sound (e.g., asthma).
• Sighs are deep inhalations followed by prolonged exhalations.
• Air hunger is deep sighing respiration accompanied by shortness of breath.
• Cheyne-Stokes respiration is hyperpnea with periods of apnea.
• Kussmaul breathing is rapid, deep breathing.

Blood Pressure

• Blood pressure (BP) is the force of blood against artery walls.
• Systolic BP is the highest pressure during ventricular contraction.
• Diastolic BP is the lowest pressure during ventricular relaxation.
• Normal BP is 120/80 mmHg.
• Mean arterial pressure (MAP) is calculated as systolic pressure + 2 x diastolic pressure. A normal MAP is between 70-100 mmHg.
• Pulse pressure = systolic blood pressure - diastolic blood pressure; normal is approximately 40 mmHg.
• Cuff size should be 20% greater than the limb diameter, with bladder width at 40% of the circumference and length at 80%.
• Avoid taking BP on an arm with an IV, injury, fistula, mastectomy, or paralysis.

Blood Transfusion

• Blood transfusion is the transfer of donated blood into a patient through an IV line.
• Packed red blood cells (PRBCs) are used to treat anemia.
• Infusion time for one unit is 2-4 hours.
• Blood is usually stored for 35-42 days at 1-6°C.
• Platelets are used to treat thrombocytopenia and platelet dysfunction and stored at 22°C for 7 days.
• Cross-matching is usually done prior to transfusion, but is not always necessary.
• Infusion time should usually be 15-30 minutes, if cross-match is performed, however it can take longer depending on the needs of the patient.
• Fresh frozen plasma (FFP) provides clotting factors and volume. FFP is stored at -40°C for 1 year.
• Cryoprecipitate is used to replace clotting factors and is also stored at -40°C for 1 year.
• Administration should take 15-30 minutes.

Blood Transfusion Complications and Issues

• Transfusion reactions (e.g., chills, rash, cyanosis, dyspnea, chest pain, fever) are dangerous and necessitate immediate intervention (stop the transfusion).
• Circulatory overload can occur due to rapid blood infusion, characterized by symptoms like dyspnea, cough, and hypertension. Slowing the transfusion rate is crucial.
• Septicemia (blood poisoning) is possible with contaminated blood.
• Iron Overload is possible and may be treated with deferoxamine (chelation).
• Hypocalcemia: citrate in transfused blood binds calcium and it's excreted, thus it's important to monitor calcium levels before and after the blood transfusion.
• Hyperkalemia: assess pre- and post-transfusion potassium levels, especially with older blood (older blood is more likely to have undergone hemolysis, which releases K+).
• Disease transmission risks (hepatitis B/C, HIV) are considerations with blood transfusions.