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(BQ) Part 2 book “Coté and Lerman''s a practice of anesthesia for infants and children” has contents: Plastic and reconstructive surgery, burn injuries, cardiopulmonary resuscitation, malignant hyperthermia, regional anesthesia, ultrasound-guided regional anesthesia, chronic pain, anesthesia outside the operating room,… and other conetnts.
SECTION VI The Abdomen OUTLINE 28 Essentials of Nephrology 29 General Abdominal and Urologic Surgery 30 Essentials of Hepatology 31 Organ Transplantation 2903 28 Essentials of Nephrology Delbert R Wigfall, John W Foreman, Warwick A Ames Renal Physiology Fluids and Electrolytes Acid-Base Balance Disease States Acute Renal Failure and Acute Kidney Injury Chronic Renal Failure Preoperative Preparation of the Child With Renal Dysfunction Preoperative Laboratory Evaluation Perioperative Dialysis Medications Intraoperative Management Strategies for Renal Protection Vascular Access Environment Fluids and Blood Products Anesthetic Agents 2904 Postoperative Concerns THE ANESTHESIA PRACTITIONER IS OFTEN FACED with a child who has acute kidney injury (AKI) or renal failure Renal disease requires the practitioner to be vigilant about fluid homeostasis, acid-base balance, electrolyte management, choice of anesthetics, and potential complications This requires a thorough understanding of the excretory and fluid homeostatic functions of the kidney, particularly in the neonate and younger child If not managed assiduously, perioperative renal dysfunction can deteriorate into renal failure or multiorgan system failure resulting in significant morbidity or mortality The anesthesia provider must understand renal physiology, appropriate preoperative preparation, intraoperative management, and postoperative care of the child with renal disease Renal Physiology The basic functions of the kidney are to maintain fluid and electrolyte homeostasis and metabolism The first step in this tightly controlled process is the production of the glomerular filtrate from the renal plasma The glomerular filtration rate (GFR) depends on renal blood flow (RBF), which depends on the systolic blood pressure and circulating blood volume The kidneys are the best perfused organs per gram of weight in the body They receive 20% to 30% of the cardiac output maintained over a wide range of blood pressures through changes in renal vascular resistance Numerous hormones play a role in this autoregulation, including vasodilators (i.e., prostaglandins E and I2, dopamine, and nitric oxide) and vasoconstrictors (i.e., angiotensin II, thromboxane, adrenergic stimulation, and endothelin) Congestive heart failure and volume contraction severely limit the ability of the kidney to maintain autoregulation When adjusted for body surface area (BSA) or scaled using allometric theory (see Chapter 7), both RBF and GFR double in the first weeks of postnatal life and both continue to increase steadily, reaching adult values by years of age (see Figs 7.11 and 7.12).1,2 The increases in RBF over time parallel similar increases in cardiac output and decreases in renal vascular resistance The initial GFR and the rate of increase during the first few years correlate with the neonate's postmenstrual age at birth 2905 For example, the GFR (corrected using BSA or allometry) of a neonate born at 28 weeks gestation is one-half of that of a full-term infant (see Figs 7.11 and 7.12).3 GFR may be estimated from the serum creatinine concentration and the height of the child according to the following formula4,5: In the equation, k is a constant that varies with age; 0.413 for infants, 0.55 for children, and 0.7 for adolescent boys The serum creatinine concentration, especially in the first days of life, reflects the maternal serum creatinine concentration and therefore cannot be used to predict neonatal renal function until at least days after birth.6 Fluids and Electrolytes The kidney regulates the total body sodium balance and maintains normal extracellular and circulating volumes.7 The adult kidney filters 25,000 mEq of sodium per day, but it excretes less than 1% through extremely efficient resorption mechanisms along the nephron The proximal tubule resorbs 50% to 70%, the ascending limb of the loop of Henle resorbs about 25%, and the distal nephron accounts for 10% of the filtered sodium load Several hormones, including renin, angiotensin II, aldosterone, and atrial natriuretic peptide (ANP), and changes in circulating blood volume contribute to maintaining the sodium balance.8 Serum osmolality is tightly regulated through changes in arginine vasopressin (AVP) release and thirst.9–11 AVP, also called antidiuretic hormone, is synthesized in the hypothalamus and stored in the posterior pituitary, where it is released in response to an increasing plasma osmolality AVP is also released in response to decreases in the circulating blood volume and hypotension, including responses to nausea, vomiting, opioids, inflammation, and surgery AVP binds to receptors in the collecting duct, increasing the permeability of the tubules to water and leading to increased water resorption and concentrated urine Neonates are much less able to conserve or excrete water compared with older children, rendering the fluid management and volume issues important tasks for the anesthesiologist in this young age group.12 The regulation of serum potassium is managed by the kidney and 2906 depends on the concentration of plasma aldosterone Aldosterone binds to receptors on cells in the distal nephron, increasing the secretion of potassium in the urine Neonates are much less efficient at excreting potassium loads compared with adults, and the normal range of serum potassium concentrations is therefore greater in neonates; Table 28.1 provides the normal values.13 Potassium regulation is affected by the acid-base status; excretion of potassium increases in the presence of alkalosis and decreases in the presence of acidosis Causes of hyperkalemia and hypokalemia are presented in Tables 28.2 and 28.3, respectively TABLE 28.1 Normal Values of Serum Potassium Age Serum Potassium Range (mEq/L) 0–1 month month–2 years 2–17 years >18 years 4.0–6.0 4.0–5.5 3.8–5.0 3.2–4.8 TABLE 28.2 Causes of Hyperkalemia Transcellular Shifts Acidosis β-Adrenergic blockers Insulin deficiency Burns Tumor lysis syndrome Rhabdomyolysis 2907 Succinylcholine Decreased Excretion Renal failure Potassium-sparing diuretics Cyclosporine Nonsteroidal antiinflammatory drugs Angiotensin-converting enzyme inhibitors Mineralocorticoid deficiency Adrenal insufficiency Congenital adrenal hyperplasia Hyporeninemic hypoaldosteronism Primary mineralocorticoid deficiency Mineralocorticoid resistance Prematurity Obstructive uropathy Pseudohypoaldosteronism Increased Intake Potassium supplements, oral or intravenous Blood transfusions 2908 Potassium-containing antibiotics TABLE 28.3 Causes of Hypokalemia Transcellular Shift Insulin β-Adrenergic agonists Increased Excretion Vomiting Diarrhea Nasogastric suction Laxatives Diuretics Cisplatin Amphotericin B Renal tubular acidosis Bartter syndrome Corticosteroids Decreased Intake Malnutrition 2909 Anorexia nervosa Acid-Base Balance The kidney is involved in the regulation of acid-base balance and the response to the stress of illness The kidney reclaims virtually all of the filtered bicarbonate in the proximal tubule and regenerates bicarbonate (HCO3−) lost in the neutralization of acid generated by the normal combustion of food, especially protein, and the formation of bone New bicarbonate is the product of cells in the distal nephron that decompose the carbonic acid (H2CO3) formed from water (H2O) and carbon dioxide (CO2) by carbonic anhydrase The protons (H+) that are generated from this process are pumped into the lumen of the collecting duct, where they combine with hydrogen phosphate (HPO42−) or ammonia (NH3) generated by the catabolism of amino acids, mainly glutamine, in the tubule cells Infants, especially neonates, maintain a slightly acidotic blood (pH = 7.37) and decreased plasma bicarbonate concentration (22 mEq/L) compared with older children and adults (pH = 7.39; plasma bicarbonate = 24 to 28 mEq/L).14 The reduced plasma concentration of HCO3− is the result of a reduced threshold or the plasma concentration at which HCO3− is incompletely resorbed by the kidney Neonates maintain acidbase homeostasis but are limited in their ability to respond to an acid load.15 This is especially true for preterm infants Disease States The causes of and differences in renal diseases between children and adults are substantive Depending on the cause of the renal disease, management may be different Adult renal disease usually results from long-standing diabetes mellitus or hypertension with an associated compromise in cardiovascular function Children may also have renal failure owing to diseases such as sickle cell disease or systemic lupus erythematosus, but cardiovascular function is far less commonly compromised 2910 Acute Renal Failure and Acute Kidney Injury Acute renal failure (ARF) or acute renal insufficiency is defined as an abrupt deterioration in the ability of the kidneys to clear nitrogenous wastes, such as urea and creatinine Concomitantly, there is a loss of ability to excrete other solutes and maintain a normal water balance This leads to the clinical presentation of acute renal insufficiency: edema, hypertension, hyperkalemia, and uremia Acute kidney injury (AKI) has almost replaced the traditional term acute renal failure (ARF), which was used in reference to the subset of patients who had an acute need for dialysis With the recognition that even modest increases in serum creatinine are associated with a dramatic increase in mortality, the clinical spectrum of acute decline in GFR is broader Minor deterioration in GFR and kidney injury are captured in a working clinical definition of kidney damage that allows early detection and intervention and uses AKI in place of ARF The term ARF is preferably restricted to those with AKI who also require renal replacement therapy.16 The prognosis of AKI is assessed in part by the use of the RIFLE criteria, which include three severity categories (i.e., Risk, Injury, and Failure) and two clinical outcome categories (Loss and End-stage renal disease) (Table 28.4) TABLE 28.4 RIFLE Classification of Renal Failure and Kidney Injury RIFLE Factors GFR Criteria Urine Output Criteria Risk Increased Cr × 1.5 or decreased GFR >25% Injury Increased Cr × or GFR decrease >50% UOP hours UOP 12 hours Failure Increased Cr × or GFR decrease of 75% or Cr ≥4 mg/dL UOP 24 hours or Acute rise ≥0.5 mg/dL Anuria > 12 hours Loss Persistent ARF: complete loss of kidney function > weeks ESKD End-stage kidney disease (> months) High sensitivity High specificity ARF, acute renal failure; Cr, creatinine; ESKD, end-stage kidney disease; GFR, glomerular filtration rate; RIFLE, Risk of renal dysfunction, Injury to the kidney, 2911 Failure of kidney function, Loss of kidney function, and End-stage kidney disease; UOP, urine output Modified from Bellomo R, Ronco C, Kellum JA, Mehta RL, Palevsky P Acute Dialysis Quality Initiative Workgroup Acute renal failure—definition, outcome measures, animal models, fluid therapy and information technology needs: the Second International Consensus Conference of the Acute Dialysis Quality Initiative (ADQI) Group Crit Care 2004;8:R204–R212 The term ARF has often been incorrectly used interchangeably with acute tubular necrosis (ATN), which usually refers to a rapid deterioration in renal function occurring minutes to days after an ischemic or nephrotoxic event Although acute tubular necrosis is an important cause of ARF, it is not the sole cause, and the terms are not synonymous For the purposes of this chapter, AKI refers to the disease formerly called ARF Etiology and Pathophysiology AKI is often multifactorial in origin or the result of several distinct insults To treat AKI, it is important to understand its causes and pathophysiology The etiologies of AKI are varied, but can be broadly classified as follows (Table 28.5): TABLE 28.5 Causes of Acute Renal Failure Prerenal Failure Renal Failure Postrenal Failure Hypovolemia Acute glomerulonephritis Obstruction Volume loss Postinfectious Gastrointestinal, renal losses Membranoproliferative glomerulonephritis Sequestration (burns, postoperative) Rapidly progressive glomerulonephritis Glomerulonephritis due to systemic disease (e.g., HUS, DIC, SLE) Hypotension Shock Vasodilators Acute interstitial nephritis Drug-induced hypersensitivity (penicillin) Infections 2912 Intrinsic (papillary necrosis due to diabetes, sickle cell disease, or analgesic nephropathy) Intrarenal abnormalities, ureteral obstruction, obstruction of the bladder or urethra Extrinsic (tumor compression, lymphadenopathy) Endsheet 5478 Endsheet 5479 5480 A Practice of Anesthesia for Infants and Children CJ Coté MD, J Lerman MD, BJ Anderson MB ChB Pocket Reference Guide Note that the drug doses and management decisions presented are those that are commonly recommended; each child's care must be individualized according to the child's underlying medical and surgical conditions All drug doses should be double checked before administration so as to avoid errors RESUSCITATION Oxygen Epinephrine (Adrenaline) Atropine Bicarbonate Calcium Chloride Calcium Gluconate Adenosine (Adenocard) Lidocaine Amiodarone (Cordarone) Procainamide (Pronestyl) Magnesium Glucose Ventilate with 100% oxygen µg/kg to treat hypotension IV; 10 µg/kg IV for cardiac arrest; repeat every 3-5 minutes as needed 20 µg/kg IV (for symptomatic bradycardia); maximum dose mg for child and mg for adolescent 1-2 mEq/kg IV to be guided by blood gas analysis for 0.05 µg/kg/min) Vasopressin (Pitressin) 0.0001-0.001 units/kg/min RULE OF SIXES 0.1 µg/kg/min = 0.6 mg/100 mL administered as body weight (kg) in mL/h µg/kg/min = mg/100 mL administered as body weight (kg) in mL/h 10 µg/kg/min = 60 mg/100 mL administered as body weight (kg) in mL/h 20 µg/kg/min = 120 mg/100 mL administered as body weight (kg) in mL/h ANAPHYLAXIS Search for cause, especially latex allergy; remove source if possible 5482 Oxygen Epinephrine (Adrenaline) Ventilate with 100% oxygen µg/kg IV to treat hypotension/bronchospasm; repeat with increasing doses every 3-5 minutes as needed; may need continuous infusion Fluid bolus Phenylephrine (Neo-Synephrine) Hydrocortisone Diphenhydramine Ranitidine (Zantac) Vasopressin 20 mL/kg balanced salt solution; repeat as necessary 0.1 µg/kg/min IV; titrate to effect if inadequate response to epinephrine 2-3 mg/kg IV 1-2 mg/kg IV 1.5 mg/kg IV 0.5-1 U/kg IV HYPERKALEMIA TREATMENT Intervention Dose Calcium chloride Calcium gluconate Hyperventilation Albuterol (Ventolin, Proventil) Salbutamol Glucose + insulin Kayexalate 5-10 mg/kg/dose IV; repeat until normal sinus rhythm 15-30 mg/kg/dose IV; repeat until normal sinus rhythm By inhalation administered with a spacer µg/kg IV over 15 Glucose (0.5-1 g/kg) with insulin (0.1 U/kg) given IV over 30-60 g/kg (up to 40 g) q4h (PO, PR, per gastric tube) LARYNGEAL MASK AIRWAY (CLASSIC) Weight (kg) Size Cuff volume (mL) Largest ETT that will fit through LMA 100 1.5 2.5 10 14 20 30 40 50 3.5 uncuffed uncuffed 4.5 uncuffed uncuffed cuffed cuffed cuffed cuffed LARYNGOSCOPE BLADES (APPROXIMATE SIZE) Age Miller Preterm Full-term neonate Term-2 years 2-6 years 6-10 years >10 years 0 2 or Wis-Hipple Macintosh 1.5 NA NA 1-2 2 or 5483 ETT SIZE (mm ID) Preterm (2 years Uncuffed Cuffed 2.5 3 Age/4 + (or 4.5) 3-3.5 4-4.5 0.5-1.0 mm smaller than uncuffed ETT* * Assure leak with deflated cuff at 20-40 cm H2O PIP DISTANCE OF INSERTION (cm) EVEN WITH GUMS Preterm (4 wk (mg/kg) (mg/kg) (mg/kg) Ampicillin/Sulbactam # Ampicillin Aztreonam Cefazolin Cefuroxime 50 q8h 30 q12h 20 q24h 25-50 q12h 50 (ampicillin) 25-50 q6h 30 q8-12h 20 q8h 25-50 q12h Repeat intraoperative dosing (h) 50 (ampicillin) max 3g 50 q6h max 2g 30 q8h max 2g 30 q8h max 2g (>120 kg, 3g) 25-50 q8h max 1.5g 4 5486 Cefotaxime Cefoxitin Cefotetan Ceftriaxone 50 q8-12h 30 q8h # 50 q24h 50 q6-8h 30-33 q8h 30 q12h 50-75 q24h 50 q6-8h max 1g 40 q8h max 2g 40 q12h max 2g 50-75 q12-24h max 2g NA Cefuroxime Ciprofloxacin Clindamycin Ertapenem Fluconazole Gentamicin (over 60 min) 25-50 q12h 10 q12h q12h # q72h q24h 25-50 q12h 10 q12h q8h 15 q12h q24h 3.5 q24h 25-50 q8h max 1g 10 q8h max 0.4g 10 q6-8h max 900 mg 15 q12h max 1g 6-12 max 0.4g NA NA NA NA Levofloxacin Metronidazole Moxifloxacin Nafcillin Piperacillin/Tazobactam # 7.5 q12h q24h 25 q8h 100 (piperacillin) q12h 2-2.5 q8h Single dose mg/kg # 15 q12h 10 q24h 25 q6h 100 (piperacillin) q8h 10 q12h max 0.5g 7.5-15 q6h max 0.5g 10 q24h max 0.4g 25-50 q4-6h max 12g/day Infants 2-9 mon (piperacillin) 80 mg/kg; NA NA NA NA > mon and ≤40 kg (piperacillin) 100 mg/kg; >40 kg (piperacillin) max 3.375g Ticarcillin Vancomycin (over 60 min) 75 q12h 15 q12h 50-75 q8h 15 q8h 33-50 q4-6h max 3.1g 10-15 q8h max 2g NA NA # Consult pharmacy for preterm or low birth weight infants and children with renal failure Current American Society of Hospital Pharmacists recommendations for surgical IV antibiotic prophylaxis weight-normalized https://www.ashp.org//media/assets/policy-guidelines/docs/therapeutic-guidelines-antimicrobialprophylaxis-surgery.ashx? la=en&hash=8387AA6F0FE4BAA7B661A1634C467E872B3DAF0A [accessed October 22, 2017] and Lexicomp Online: http://www.wolterskluwercdi.com/lexicomp-online/ ANTIHISTAMINES Diphenhydramine (Benadryl) Ranitidine (Zantac) Famotidine (Pepcid) ANTIEMETICS 5487 IV (mg/kg) PO (mg/kg) 1-1.25 1.5 0.5 1-1.5 2-5 0.5 ANTIEMETICS Dexamethasone Metoclopramide (Reglan) Ondansetron (Zofran) Tropisetron (Navoban) Palonosetron (Aloxi) IV (mg/kg) PO (mg/kg) 0.0625-0.15 (max 10-15 mg) 0.15 0.15 0.05-0.1 up to a maximum total dose of mg 0.1-0.2 0.1 up to mg 1.5-20 µg/kg (max 1.5 mg) (limited data in children) Aprepitant (max 125 mg) for mo to 145 mEq/L) with serum hyperosmolality (>300 mOsm/L) DDAVP (desmopressin) 1-10 mU/kg/h (0.0025-0.025 µg/kg/h), titrate to effect (4 µg = 16 IU) von Willebrand Disease (VWD) (Treatment depends on the type) Desmopressin (DDAVP) 0.3 µg/kg IV once 30 minutes preoperatively (avoid in Type 2B) 5490 Amicar 100 mg/kg IV or PO hour preoperatively, then q4-6h depending on the type of VWD SBE REGIMEN FOR DENTAL SURGERY Route Antibiotic dose Oral IV (unable to take oral medication) Oral (allergy to penicillins) Amoxicillin 50 mg/kg PO Ampicillin, Cefazolin, or Ceftriaxone 50 mg/kg IV Cephalexin 50 mg/kg or Clindamycin 20 mg/kg or Azithromycin 15 mg/kg PO Cefazolin or ceftriaxone 50 mg/kg or clindamycin 20 mg/kg IV IV (allergy to penicillins and unable to take oral medication) For complete listing of SBE indications for other surgeries/procedures, see http://www.heart.org/idc/groups/heartpublic/@wcm/@hcm/documents/downloadable/ucm_307644.pdf NORMAL HEMODYNAMIC INDICES AND WEIGHT Mean systolic blood pressure (mm Hg) in preterm and term infants Gestational age at birth Day of life 24 41 28 44 32 50 36 56 40 63 Age Preterm 0-3 months 3-6 months 6-12 months 1-3 years 3-6 years 6-12 years 12-20 years Day 10 of life 52 62 69 76 83 Normal blood pressure (mm Hg) Mean Mean systolic diastolic 55-75 35-45 65-85 45-55 Mean heart rate (beats/min) Weight range 10th-90th percentile 120-170 100-150 2.5-7.5 70-90 50-65 90-120 4.8-9.5 80-100 55-65 80-120 6.5-12.5 90-105 95-110 100-120 110-135 55-70 60-75 60-75 60-75 70-110 65-110 60-95 55-85 8.75-17 15.5-25 17-55 30-86 Simple formula to predict weight from age: Infants 1-11 mo: Wt (kg) = (Age [months] + 9)/2 Children 1-4 yr: Wt (kg) = × (Age [yr] + 5) Children 5-14: Wt (kg) = × Age (yr) 5491 Instructions for online access Thank you for your purchase Please note that your purchase of this Elsevier eBook also includes access to an online version Please click here (or go to http://ebooks.elsevier.com) to request an activation code and registration instructions in order to gain access to the web version 5492 ... decreases in the presence of acidosis Causes of hyperkalemia and hypokalemia are presented in Tables 28 .2 and 28 .3, respectively TABLE 28 .1 Normal Values of Serum Potassium Age Serum Potassium Range... Induction of anesthesia may be carried out safely as long as the child is euvolemic and the pharmacokinetics and pharmacodynamics of the induction agent are understood and accounted for Anesthetic agents... needs of the child postoperatively to minimize volume overload and pulmonary edema Regional anesthesia is a viable alternative to general anesthesia or an adjunct in many cases The anesthesia team