A 45-year-old solicitor had an onset of severe, crushing, substernal chest pain while attending a football match. He collapsed on his way to the car. Bystander Cardiorespiratory Resuscitation was begun immediately and continued until arrival in Casualty where an endotracheal tube was inserted and ventilation was maintained on 100% oxygen. Investigations revealed: pH 7.13 PaO2 560 mmHg PaCO2 18 mmHg Bicarbonate 5.8 SaO2 98% Based on these laboratory values, which of the following statements best describes his current pathophysiology? 1) He is demonstrating a primary respiratory alkalosis 2) He probably developed a large right to left intracardiac shunt 3) His anion gap is probably normal 4) His oxyhemoglobin curve is shifted to the left 5) His pulmonary artery pressure is probably elevated

1 Answer

Answer :

Answers-5  This young patient with severe central chest pain has probably arrested due to myocardial infarction and arrhythmia. His gases reveal high PO2 following 100% O2 but severe acidosis due to the arrest and lactic acidosis thus anion gap would be high. He does not have a primary ventilatory failure as his PO2 is high. There is no left to right shunting and high pulmonary pressures would be expected after this arrest scenario.

Related questions

Description : A 19 year-old female is referred following a visit to the dentist where marked erosion of her teeth was noted. She was entirely asymptomatic and her only medication was the oral contraceptive pill ... ) Bulimia nervosa 2) Conn's syndrome 3) Laxative abuse 4) Pregnancy 5) Primary hypoparathyroidism

Last Answer : Answers-5 This patient has tooth erosion associated with hypokalaemic metabolic alkalosis and hypocalcaemia. This suggests a diagnosis of hypoparathyroidism. Conn's is unlikely in this age group, is ... raised alkaline phosphatase would not be expected. Early pregnancy would not fit this picture.

Description : All the following statements about renal tubular acidosis are correct except (A) Renal tubules may be unable to reabsorb bicarbonate (B) Renal tubules may be unable to secrete hydrogen ions (C) Plasma chloride is elevated (D) Anion gap is decreased

Last Answer : Answer : D

Description : Salicylate poisoning can cause (A) Respiratory acidosis (B) Metabolic acidosis with normal anion gap (C) Metabolic acidosis with increased anion gap (D) Metabolic alkalosis

Last Answer : Answer : C

Description : The primary event in respiratory alkalosis is (A) Rise in pH (B) Decrease in pCO2 (C) Increase in plasma bicarbonate (D) Decrease in plasma chloride

Last Answer : Answer : B

Description : All the following features are found in blood chemistry in uncompensated lactic acidosis except (A) pH is decreased (B) Bicarbonate is decreased (C) pCO2 is normal (D) Anion gap is normal

Last Answer : Answer : D

Description : True statements about the cerebral blood flow include: a. it is constant for the blood pressure in the range between 50-150mmHg b. the blood pressure is affected more by the PaO2 than PaCO2 c. hypocapnia causes vasoconstriction d. cerebral arterioles constricts when the blood pressure raises

Last Answer : it is constant for the blood pressure in the range between 50-150mmHg

Description : A 53-year-old man presented with hypertension of 150/110 mmHg. He is generally asymptomatic and has no previous medical history of note. He is a smoker of 5 cigarettes daily and drinks ... Adrenocortical adenoma 2) Bartter's syndrome 3) Liddle's syndrome 4) Liquorice ingestion 5) Pheochromocytoma

Last Answer : Answers-1 This patient is most likely to have Conn's syndrome as reflected by the hypokalaemic hypertension. Liquorice ingestion or Liddle's syndrome are again possible causes of ... hypertension (often diastolic hypertension), muscular weakness, paresthesias, headache, polyuria, and polydipsia."

Description : A young child presents with respiratory distress, worsening over 2 days. Blood gases show a pH of 7.25, a PCO2 of 7.5kPa, a PO2 of 8.5kPa, and a base excess of -4. Which of the ... required. 4) Results are consistent with late severe asthma. 5) Bicarbonate may be necessary to correct the acidosis.

Last Answer : Answers-4 In interpreting blood gas results, the following sequence may be useful: Inspect the pH: Is it low, normal or high? Inspect the CO2: Is it low, normal or high? Inspect the PO2: Is ... excess and normal pH. Bicarbonate is usually only considered if the base deficit exceeds about -8 or 00.

Description : 2, 3-Biphosphoglycerate in high concentrations, combines with hemoglobin, causes (A) Displacement of the oxyhemoglobin dissociation curve to the left (B) Displacement of the oxyhemoglobin dissociation curve ... (C) No change in oxy hemoglobin dissociation curve (D) Increased affinity for oxygen

Last Answer : Answer : B

Description : If the body undergoes alkalosis the respiratory center located in the medulla gets the information and induces the lowering of the respiratory frequency. The reduction of the respiratory frequency makes ... of bicarbonate towards the production of more hydrogen ions and thus the blood pH lowers.

Last Answer : What is the difference between respiratory acidosis and metabolic acidosis and what is the difference between respiratory alkalosis and metabolic alkalosis?

Description : Which of the following statements concerning monitoring techniques in the intensive care unit are true? A. Pulmonary artery and pulmonary capillary wedge pressure readings should be made ... clinical conditions not associated with tissue hypoxia, including liver disease and hypermetabolic states.

Last Answer : Answer: BD DISCUSSION: Many different monitoring techniques may be used to assess the adequacy of therapy for shock. The pulmonary artery catheter can provide important hemodynamic and oxygen ... also be seen with liver disease, toxin ingestion, and hypermetabolic states not associated with shock

Description : Which of the following features are present in blood chemistry in uncompensated metabolic alkalosis except? (A) Increased pH (B) Increased bicarbonate (C) Normal chloride (D) Normal pCO2

Last Answer : Answer : D

Description : The oxygen d issoc iat ion curve for hemoglobin is shifted to the right by (A) Decreased O2 tension (B) Decreased CO2 tension (C) Increased CO2 tension (D) Increased pH

Last Answer : Answer : C

Description : Which of the following statement(s) is/are true concerning CO2 transfer in the lung? a. Carbon dioxide excretion is a direct function of alveolar ventilation b. Normally end tidal ... d. Positive pressure ventilation under normal airway pressures creates a significant end tidal PaCO2 gradient

Last Answer : Answer: a, b, c The amount of carbon dioxide excretion is directly related to alveolar ventilation. While oxygenation is a function of matching blood flow to alveoli, carbon dioxide excretion is ... high (over 30 cm H2O) and the compression volume is a significant component of each exhaled breath

Description : The figure shows blood circulation in humans with labels A to D. Select the option which gives correct identification of label and functions of the part. (a) B - Capillary-Thin without muscle layer and ... blood to heart, pO2 = 95 mmHg (d) A - Artery-Thick walled and blood flows evenly

Last Answer : (c) D - Pulmonary vein-Takes oxygenated blood to heart, pO2 = 95 mmHg

Description : Which of the following statement(s) is/are true concerning the relationship between cardiac function and effective blood volume? a. A pulmonary capillary wedge pressure of 5-10 rules out ... sole purpose of a pulmonary artery catheter is to measure pulmonary artery pressure and cardiac output

Last Answer : Answer: b, c Although physical findings are often adequate to establish a diagnosis and institute management of cardiac failure, direct measurement of filling pressures of the right heart ( ... blood volume is normal, filling pressures are normal, and total body extracellular fluid is excessive

Description : A patient has developed a sever chest pain and difficulties in breathing while in the dental chair. Your initial response is: a. Administer glycerine trinitrate and monitor patient in upright ... required until confirmed as MI by ECG d. Patient has myocardial infarction as confirmed by ECG

Last Answer : a. Administer glycerine trinitrate and monitor patient in upright position.

Description : A patient has developed a sever chest pain and difficulties in breathing while in the dental chair. Your initial response is: A. Administer glycerine trinitrate and monitor patient in upright ... required until confirmed as MI by ECG D. Patient has myocardial infarction as confirmed by ECG

Last Answer : A. Administer glycerine trinitrate and monitor patient in upright position

Description : A 16 year old male with a day history of malaise, weakness and vomiting. He was diagnosed with Insulin dependent diabetes mellitus 3 years prviously. Which ONE of the following supports a diagnosis of ... serum glucose 14 mmol/l 4) Decreased appetite in the past few days 5) Shallow respirations

Last Answer : Answers-2 a-An unusual but recognised feature particularly in children. However does not support a diagnosis of DKA. b-Suggests metabolic acidosis. c-'Normoglycaemic DKA' can occur and a glucose ... anorexia. e-Respiratory compensation leads to rapid deep (Kussmaul's) breathing. (Dr Mike Mulcahy)

Description : Which of the following statements are true of elevated-anion gap metabolic acidosis? A. Hypoperfusion from the shock state rarely produces an elevated anion gap. B. Retention of sulfuric and phosphoric ... E. Use of lactated Ringer's solution is inappropriate in the treatment of lactic acidosis.

Last Answer : Answer: BC DISCUSSION: An elevated anion gap may be produced by lactic acidosis from shock or by retention of inorganic acids from uremia. Lactated Ringer's solution rapidly corrects the ... . Bicarbonate loss from diarrhea and dilutional acidosis are non-anion gap types of metabolic acidosis

Description : Which of the following statement(s) is/are true concerning the pathophysiology of gas exchange? a. Hypoventilation in relation to perfusion can result in an oxygen saturation of less than 100% ... does not occur under normal circumstances d. The normal arterial oxygen saturation should be 100%

Last Answer : Answer: a, b Under normal conditions, red blood cells in the pulmonary capillaries become fully saturated and oxygen dissolves in plasma resulting in blood PO2 of 100 and O2 saturation of 100%. This ... the fact that normal arterial PO2 is 90-100 mm Hg and the normal O2 saturation is 98%

Description : Which of the following ranges identifies the amount of pressure within the endotracheal tube cuff that is believed to prevent both injury and aspiration? a) 20-25 mm Hg water pressure. Usually the ... pressure A measure of 0-5 mm Hg water pressure would indicate that the cuff is underinflated.

Last Answer : a) 20-25 mm Hg water pressure. Usually the pressure is maintained at less than 25 cm water pressure to prevent injury and at more than 20 cm water pressure to prevent aspiration.

Description : A 68-year-old male who underwent a repair of an abdominal aortic aneurysm 5 days ago, develops tachycardia, tachypnea, hypotension with cool, pale, mottled cyanotic extremities. He ... use of moderate doses of inotropic agents e. Afterload reduction with nitroprusside is absolutely contraindicated

Last Answer : Answer: a, b, d Intrinsic cardiogenic shock results from failure of the heart as an effective pump. Coronary artery disease is the most common cause of myocardial ... hemodynamic monitoring. Infusion of afterload-reducing agents can be administered in conjunction with inotropic support

Description : A 22-year-old man sustains a single stab wound to the left chest and presents to the emergency room with hypotension. Which of the following statement(s) is/are true concerning his ... diagnosis of pericardial tamponade d. The placement of bilateral chest tubes will likely resolve the problem

Last Answer : Answer: c Shock from cardiac compression occurs when external pressure on the heart impairs ventricular filling. Because ventricular filling is a function of venous return and myocardial compliance, ... sternotomy. Chest tube placement would not be appropriate as the sole treatment in this patient

Description : When the balloon on the distal tip of a pulmonary artery catheter is inflated and a pressure is measured, the measurement obtained is referred to as the a) pulmonary artery wedge ... Cardiac output is determined through thermodilution involving injection of fluid into the pulmonary artery catheter.

Last Answer : a) pulmonary artery wedge pressure. When the balloon is inflated, the tip of the catheter floats into smaller branches of the pulmonary arty until it can no longer be passed and the pressure is recorded, reflecting left atrial pressure and left ventricular end-diastolic pressure.

Description : All of the following statements about hemorrhagic shock are true except: A. Following hemorrhagic shock, there is an initial interstitial fluid volume contraction. B. Dopamine, or a similar inotropic ... shock, a narrowed pulse pressure is commonly seen before a fall in systolic blood pressure.

Last Answer : Answer: BC DISCUSSION: Hemorrhagic shock is associated with a contraction of the interstitial fluid compartment because of precapillary vasoconstriction and reabsorption of interstitial fluid ... definitive evidence that such solutions are better than standard crystalloid solutions is lacking

Description : A world-famous magician and his young assistant were observed walking slowly along in a department store when suddenly they both stopped walking and began to slowly rise from the floor. The two ... and his assistant accomplished this feat, and why didn't the onlookers express amazement? -Riddles

Last Answer : The magician and his assistant were simply using an escalator to go up to the next floor in the department store.

Description : The oxygen dissociation curve is shifted to the right with: a. polycythaemia b. pyrexia c. respiratory acidosis d. sickle cell anaemia

Last Answer : pyrexia

Description : Bohr effect is (A) Shifting of oxyhemoglobin dissociation curve to the right (B) Shifting of oxyhemoglobin dissociation curve to the left (C) Ability of hemoglobin to combine with O2 (D) Exchange of chloride with carbonate

Last Answer : Answer : A

Description : Anion gap of plasma can be due to the presence of all the following except (A) Bicarbonate (B) Lactate (C) Pyruvate (D) Citrate

Last Answer : Answer : A

Description : Anion gap is the difference in the plasma concentrations of (A) (Chloride) – (Bicarbonate) (B) (Sodium) – (Chloride) (C) (Sodium + Potassium) – (Chloride + Bicarbonate) (D) (Sum of cations) – (Sum of anions)

Last Answer : Answer : C

Description : During compensation of respiratory alkalosis, all the following changes occur except (A) Decreased secretion of hydrogen ions by renal tubules (B) Increased excretion of sodium in urine (C) Increased excretion of bicarbonate in urine (D) Increased excretion of ammonia in urine

Last Answer : Answer : D

Description : Respiratory alkalosis is caused by (A) An increase in carbonic acid fraction (B) A decrease in bicarbonic fraction (C) A decrease in the carbonic acid fraction (D) An increase in bicarbonate fraction

Last Answer : Answer : C

Description : Plasma bicarbonate is increased in (A) Respiratory alkalosis (B) Metabolic alkalosis (C) Respiratory acidosis (D) Metabolic acidosis

Last Answer : Answer : B

Description : Plasma bicarbonate is decreased in (A) Respiratory alkalosis (B) Respiratory acidosis (C) Metabolic alkalosis (D) Metabolic acidosis

Last Answer : Answer : D

Description : Match the items given in column I with those in column II and select the correct option given below. Column I Column II A. Tricuspid valve (i) Between left atrium and left ventricle B. Bicuspid valve (ii) Between right ventricle and ... (b) (i) (iii) (ii) (c) (i) (ii) (iii) (d) (ii) (i) (iii)

Last Answer : (a) (iii) (i) (ii)

Description : Match the items given in Column I with those in Column II and select the correct option given below: Column I Column II a. Tricuspid valve i. Between left atrium and left ventricle b. Bicuspid valve ii. Between right ventricle and ... a b c (1) iii i ii (2) i iii ii (3) i ii iii (4) ii i iii

Last Answer : (1) iii i ii

Description : Acidosis is the condition in which the blood pH is abnormally low. Alkalosis is the condition in which the blood pH is abnormally high. Normal pH levels for the human blood are between 7.35 and 7.45 - slightly alkaline.

Last Answer : How does the breathing process correct acidosis?

Description : A 40-year-old politician suffered from attacks of chest pain diagnosed as angina pectoris. He had a tense personality, resting heart rate was 96/min, blood pressure 170/104 mm Hg, but ... antihypertensive for initial therapy in his case: A. Nifedipine B. Hydrochlorothiazide C. Atenolol D. Methyldopa

Last Answer : C. Atenolol

Description : A 59-year-old trauma patient has suffered multiple septic complications including severe pneumonia, intraabdominal abscess, and major wound infection. He has now developed signs of multisystem organ ... the same extent d. In patients with hepatic failure, carbohydrate load should be increased

Last Answer : Answer: a, b The most severe complication of sepsis is multiple system organ dysfunction syndrome, which may result in death. The development of organ failure requires changes in the ... should be provided as fat emulsion. If encephalopathy develops, protein load should also be reduced0

Description : Which of the following statements regarding the use of a current measuring instrument is correct? A. It must be connected in series with the circuit. B. You should always start with the lowest range ... of polarity. D. An external shunt is generally utilized where current is less than 10 amperes.

Last Answer : Answer: A

Description : The given figure shows schematic plan of blood circulation in humans with labels A to D. Identify the label and give its functions. (a) C - Vena cava - Takes blood from body parts to right auricle, pCO2 = 45 ... 60 mm Hg (d) B - Pulmonary artery - Takes blood from heart to lungs, pO2 = 90 mm Hg

Last Answer : (a) C - Vena cava - Takes blood from body parts to right auricle, pCO2 = 45 mm Hg

Description : A 67-year-old male with advanced cholangiocarcinoma develops gram-negative sepsis. Excessive bleeding is noted around vascular catheters and from needle puncture sites. The diagnosis of disseminated ... b. Decreased fibrinogen level c. Normal prothrombin time d. Elevated fibrin split products

Last Answer : Answer: a, b, d Disseminated intravascular coagulation (DIC) is the primary form of acute thrombosis. Causes of this syndrome include abruptio placenta, gram-positive and gram-negative sepsis, ... decline in the platelet count and fibrinogen level, along with an elevation of fibrin split products

Description : When the patient who has experienced trauma to an extremity complains of severe burning pain, vasomotor changes, and muscles spasms in the injured extremity, the nurse ... heterotrophic ossification. Heterotrophic ossification causes muscular pain and limited muscular contraction and movement.

Last Answer : a) reflex sympathetic dystrophy syndrome. RSD is frequently chronic and occurs most often in women.

Description : Normal anion gap in plasma is about (A) 5 meq/L (B) 15 meq/L (C) 25 meq/L (D) 40 meq/L

Last Answer : Answer : B