1、UNIT IIINursing Sciences,UNIT III Nursing Sciences,Acid-Base Balance,Chapter 10,Pyramid terms,Allens test 艾伦实验Compensation 补偿，代偿Metabolic acidosis 代谢酸中毒Respiratory acidosis 呼吸酸中毒Metabolic alkalosis代谢碱中毒Respiratory alkalosis呼吸碱中毒,CRITICAL THINKING,What Should You Do?The nurse performs an Allens test
2、on a client scheduled for an arterial blood gas draw from the radial artery. On release of pressure from the ulnar artery, color in the hand returns after 20 seconds. The nurse should take which action(s)?,Regulatory Systems for Hydrogen Ion Concentration in the Blood,BOX 10-1,Regulatory Systems for
3、 Hydrogen Ion Concentration in the Blood,Buffers血液缓冲系统Hemoglobin system血红蛋白Plasma protein system血浆蛋白Carbonic acid-bicarbonate system碳酸及碳酸氢根缓冲系统Phosphate buffer system磷酸盐缓冲系统,Regulatory Systems for Hydrogen Ion Concentration in the Blood,Lungs肺Monitor the clients respiratory status closely. In acidos
4、is, the respiratory rate and depth increase in an attempt to exhale acids. In alkalosis, the respiratory rate and depth decrease; CO 2 is retained to neutralize and decrease the strength of excess bicarbonate.,Only for volatile acids,Regulatory Systems for Hydrogen Ion Concentration in the Blood,Kid
5、neys肾排氢保碱Act slowly but compensation more thorough and selectiveActing by selective regulation of bicarbonate,排H+保HCO3(bicarbonate retaining),Na+ + HCO3-, H2CO3 CO2 + H2O,磷酸盐酸化 （phosphate acidification）,Na2HPO4, NaH2PO4,氨的排泄 ( ammonia excretion),NH4+ NH4Cl,NH4+,Potassium exchange钾离子的交换,H+,H+,acidosi
6、s,H+,H+,alkalosis,When the client experiences an acid-base imbalance, monitor the potassium level closely because the potassium moves in or out of the cells in an attempt to maintain acid-base balance.,pH,acidosis alkalosis,metabolic respiratory,原因,Simple acid-base disturbance,. Respiratory acidosis
7、,Causes: Box 10-2Assessment: Table 10-1,Causes of respiratory acidosis,Asthma 哮喘Atelectasis 肺不张Brain trauma 脑外伤Bronchiectasis 支气管扩张Bronchitis 支气管炎Central nervous system depressants CNS抑制剂Emphysema 肺气肿Hypoventilation 通气不足Pulmonary edema 肺水肿Pneumonia 肺炎Pulmonary emboli 肺栓塞,Box 10-2,Any condition that
8、causes an obstruction of the airway or depresses the respiratory system can cause respiratory acidosis.,Interventions,Administer oxygen as prescribedSemi-Fowlers position半卧位Encourage and assist the client to turn, cough, and deep-breathe鼓励并协助病人翻身、咳嗽及深呼吸Encourage hydration to thin secretions鼓励病人多喝水Su
9、ction the clients airway, if necessary吸痰 Monitor electrolyte values, particularly the potassium level,. Respiratory Alkalosis,Description: accumulation of base, orA loss of acid without a comparableLoss of base H2CO3 不足,pH,. Respiratory Alkalosis,Causes: Overstimulation of respiratory systemFever发热H
10、yperventilation 过度通气Hypoxia 缺氧Hysteria癔病（歇斯底里）Overventilation by mechanical ventilatorPain,. Respiratory Alkalosis,Interventions:Assist with breathing techniques and breathing acids as prescribed.a. Encourage voluntary holding of the breath if appropriateb. Provide use of a rebreathing mask as presc
11、ribedc. Provide carbon dioxide breaths as prescribed (rebreathing into a paper bag) Monitor electrolyte values, paticular potassium and calcium levels.Prepare to administer calcium gluconate for tetany（手足抽搐）as prescribed.,. Metabolic Acidosis,Description: loss of too much base or/and retention of re
12、tention of toomuch acid buffer base ,pH,Causes of Metabolic Acidosis,Diabetes mellitus（糖尿病）of diabetic ketoacidosis（酮症酸中毒）Excessive ingestion of aspirin过度摄入阿司匹林High-fat dietInsufficient metabolism of carbohydratesMalnutritionRenal insufficiency, acute kidney injury, or chronic kidney diseaseSevere d
13、iarrhea,. Metabolic Acidosis,Assessment:Hyperpnea(呼吸急促) with Kussmauls respiration occurs (see Table 10-1),. Metabolic Acidosis,Interventions:Assess level of consciousness for central nervous system depressionMonitor intake and output and assist with fluid and electrolyte replacement as prescribedPr
14、epare to administer solutions intravenously as prescribed to increase the buffer base.Initiate safety and seizure precautions.Monitor the serum potassium level closely.Interventions in diabetes mellitus and diabetic ketoacidosis.Give insulin as prescribed,Monitor the client experiencing severe diarr
15、hea for manifestations of metabolic acidosis.,. Metabolic Alkalosis,Description: accumulation of base orA loss of acid without a comparableloss of base H2CO3 deficit ,pH,Causes of Metabolic Alkalosis,Dysfunction of metabolism代谢功能障碍Diuretics利尿剂Excessive vomiting or gastrointestinal suctioningHyperald
16、osteronismIngestion of and/or infusion of excess sodium bicarbonateMassive transfusion of whole blood,. Metabolic Alkalosis,Assessment:Respiratory rate and depth decrease toconserve CO2(see Table 10-2),. Metabolic Alkalosis,Interventions:Monitor potassium and calcium serum levels. Prepare to adminis
17、ter medications to promote the kidney excretion of bicarbonate. Prepare to replace potassium chloride as prescribed.,. Arterial Blood Gases动脉血气,A: Collection of an arterial blood gasSpecimen,1. Obtain vital signs.2. Determine whether the client has an arterial line in place (allows for arterial bloo
18、d sampling without further puncture to the client).3. Perform the Allens test to determine the presence of collateral circulation 4. Assess factors that may affect the accuracy of the results, such as changes in the O 2 settings, suctioning within the past 20 minutes, and clients activities.5. Provi
19、de emotional support to the client.6. Assist with the specimen draw by preparing a heparinized syringe (if not already prepackaged).7. Apply pressure immediately to the puncture site following the blood draw; maintain pressure for 5 minutes or for 10 minutes if the client is taking an anticoagulant.
20、8. Appropriately label the specimen and transport it on ice to the laboratory.9. On the laboratory form, record the clients temperature and the type of supplemental oxygen that the client is receiving.,Allens Test,1. Explain the procedure to the client.2. Apply pressure over the ulnar and radial art
21、eries simultaneously.3. Ask the client to open and close the hand repeatedly.4. Release pressure from the ulnar artery while compressing the radial artery.5. Assess the color of the extremity distal to the pressure point.6. Document the findings.,4-step,Step 1pHalkalosis碱中毒pHacidosis酸中毒Step 2 Pco2 +
22、pH respiratory acidosis呼吸性酸中毒Pco2 +pHrespiratory alkalosis呼吸性碱中毒Step 3 HCO3- +pH metabolic alkalosis代谢性碱中毒HCO3- +pH metabolic acidosis代谢性酸中毒Step 4 Compensation,CRITICAL THINKING,What Should You Do?The nurse performs an Allens test on a client scheduled for an arterial blood gas draw from the radial
23、artery. On release of pressure from the ulnar artery, color in the hand returns after 20 seconds. The nurse should take which action(s)?,Failure to determine the presence of adequate collateral circulation could result in severe ischemic injury to the hand if damage to the radial artery occurs with
24、arterial puncture. Upon release of pressure on the ulnar artery, if pinkness fails to return within 6 to 7 seconds, the ulnar artery is insufficient, indicating that the radial artery should not be used for obtaining a blood specimen. Another site needs to be selected for the arterial puncture and t
25、he health care provider needs to be notified of the finding.,The nurse reviews the arterial blood gas results of a client and notes the following: pH 7.45, Pco 2 of 30 mm Hg, and HCO3- of 20 mEq/L. The nurse analyzes these results as indicating which condition?1. Metabolic acidosis, compensated2. Re
26、spiratory alkalosis, compensated3. Metabolic alkalosis, uncompensated4. Respiratory acidosis, uncompensated,2,The nurse is caring for a client with a nasogastric tube that is attached to low suction. The nurse monitors the client, knowing that the client is at risk for which acid-base disorder?1. Me
27、tabolic acidosis2. Metabolic alkalosis3. Respiratory acidosis4. Respiratory alkalosis,2,A client who is found unresponsive has arterial blood gases drawn and the results indicate the following: pH is 7.12, Pco 2 is 90 mm Hg, and HCO3- is 22 mEq/L. The nurse interprets the results as indicating which
28、 condition?1. Metabolic acidosis with compensation2. Respiratory acidosis with compensation3. Metabolic acidosis without compensation4. Respiratory acidosis without compensation,4,The nurse reviews the blood gas results of a client with atelectasis. The nurse analyzes the results and determines that
29、 the client is experiencing respiratory acidosis. Which result validates the nurses findings?1. pH 7.25, Pco 2 50 mm Hg2. pH 7.35, Pco 2 40 mm Hg3. pH 7.50, Pco 2 52 mm Hg4. pH 7.52, Pco 2 28 mm Hg,1,The nurse plans care for a client with chronic obstructive pulmonary disease (COPD), understanding that the client is most likely to experience what type of acid-base imbalance?1. Metabolic acidosis2. Metabolic alkalosis3. Respiratory acidosis4. Respiratory alkalosis,3,
