By M. Surus. Roberts Wesleyan College.
Employing vasopressin during cardiopulmonary resuscitation and vasodilatory shock as a life sparing vasopressor generic 10 mg rizatriptan with mastercard. The effects of vasopressin on hemodynamics and renal function in severe septic shock: A case series rizatriptan 10 mg fast delivery. Intravenous arginine-vasopressin in children with vasodilatory shock after cardiac surgery purchase genuine rizatriptan online. Vasopressin pressor effects in critically ill children during evaluation for brain death and organ recovery. Use of vasopressin in refractory hypotension in children with vasodilatoy shock: Five cases and a review of literature, Pediatr Crit Care Med 2002;3:15. Terlipressin as rescue therapy for intractable hypotension during neonatal septic shock. Rescue treatment with terlipressin in children with refractory septic shock: A clinical study. Ischemic skin lesions as a complication of continuous vasopressin infusion in catecholamine-resistant vasodilatory shock: Incidence and risk factors. Intravenous infusion of inotropic agents (excluding dopamine < 5mg/kg/min) Respiratory system 1. PaO2/FiO2 < 200 in the absence of cyanotic congenital heart disease Neurologic system 1. Each of these pathogenic processes contributes to, and is affected by both ischemia/reperfusion and inflammation. The endothelial response to ischemia/reperfusion is characterized by four major activities: vasomotor, coagulation, permeability and inflammation. It is, therefore a regulatory process for the proliferation and differentiation of cells. Two Hit Theory Any severe impact to the human body, such as prolonged shock or traumatic or surgical injury, can directly induce the development of organ dysfunction. Possible mechanisms include ischemia, reperfusion injury, or immediate tissue destruction due to trauma. Activated endothelium exhibits procoagulant state leads to intravascular thrombin formation. Generalized activation of coagulation system leads to disseminated intravascular coagulation. The embolization of micro-vessels by the continuous and latent coagulation is important in the development of microcirculatory dysfunction and organ failure. Baseline and subsequent functions of the organ systems that need to be monitored are listed in Table 18. Ensure adequate cardiac output and treat shock states by early goal directed initial resuscitation. Newer therapies: These therapies requires larger randomised controlled trials to prove their efficacy in treatment. Mortality depends on the number of organs affected: Two organs, 29%; three organs, 38%; four organs, 84%; five or more 100%. Mortality associated with multiorgan dysfunction system and sepsis in pediatric intensive care unit. Mortality rate in pediatric septic shock with and without multiple organ system failure. Epidemiology of sepsis and multiorgan dysfunction syndrome in children Chest 1996;109:1033-37. Paediatric multiple organ dysfunction syndrome intensive care world 1997;14:78- 82. Coagulation/fibrinolysis abnormality and vascular endothelial damage in the pathogenesins of thrombocytopenic multiple organ failure. Early circulating lymphocyte apoptosis in human septic shock is associated with poor outcome Shock 2002;18:487-94. Apoptotic cell death in patients with septic shock and multiorgan dysfunction, Crit Care Med 1999;27:1230-51. Monitoring is not therapy and as clinicians/intensivists we must learn what variables to measure, measure them correctly, institute effective therapies where available and do this with minimum risk to the patient. Monitors used for purpose of patient monitoring present raw data without much intelligent integration. Hence these devices should serve as adjunct and not replacement for clinical skills. Warning: Audiovisual alarms in various monitors alert the clinician to untoward events. Hemodynamic monitoring systems are used to guide therapies designed to support the cardiovascular system in cases of circulatory instability. Adequate oxygen delivery to all tissue beds is the fundamental goal of resuscitative measures. The determinants of CaO2 are hemoglobin (Hb), oxygen saturation (SaO2) and dissolved O2 (PaO2). Thus it is clear that adequacy of circulation can be assessed by an integrated monitoring of heart rate, blood pressure, cardiac output, Hb %, SaO2 and PaO2. Of the variables that determine or depend on cardiac output, only the heart rate and blood pressure can be easily measured. Monitoring the change in trends of heart rate in response to therapy or intervention is very useful. Blood pressure: Blood pressure measurement is integral in the support of the critically ill patients. Cardiac output and systemic vascular resistance determine the mean blood pressure. When cardiac output falls, normal blood pressure is maintained by compensatory vasoconstriction causing high systemic vascular resistance. Hence as clinicians one must not feel reassured by the presence of a normal blood pressure. Forward flow to vital organs, necessary for oxygen delivery depends on the presence of a pressure gradient or perfusion pressure. A discrepancy in the volume of peripheral and central pulses may be caused by vasoconstriction or decreased cardiac output. End organ perfusion: Decreased skin perfusion manifests as prolonged capillary refill and may be a sign of shock and decreasing cardiac output provided temperature abnormalities as cause for poor perfusion are ruled out.
Magnetic resonance imaging of the lumbar plexus and retroperitoneum is indicated if tumor or hematoma is suspected (Fig discount rizatriptan generic. The umbilicus 10mg rizatriptan amex, anterior-superior iliac spine cheap rizatriptan 10mg on line, and inguinal ligament are identified by visual inspection and palpation and an imaginary line is drawn between the anterior-superior iliac spine and the umbilicus (Fig. A linear high-frequency ultrasound transducer is placed in a plane perpendicular with the inguinal ligament with the inferior aspect of the transducer lying over the anterior-superior iliac spine and the superior aspect of the transducer pointed directly at the umbilicus and an ultrasound survey scan is obtained (Fig. The hyperechoic anterior-superior iliac spine and its acoustic shadow is identified, as are the external 684 oblique, internal oblique, and transversus abdominis muscles, which extend outward from it (Fig. The fascial plane between the internal oblique and transversus abdominis muscles are then identified and the ilioinguinal nerve should be easily identifiable as a ovoid hypoechoic structure highlighted by a hyperechoic epineurium lying close to the anterior superior iliac spine (Fig. The iliohypogastric nerve may also be seen lying medial to the ilioinguinal nerve in the same fascial plane (Fig. Color Doppler may be used to aid in identifying the fascial plane between the internal oblique and transversus abdominis muscles as this plane is also shared with the deep circumflex iliac artery (Fig. After the ilioinguinal nerve is identified, the nerve is evaluated for obvious abnormality and compression by abnormal mass, tumor, scar tissue, and aneurysm. To perform ultrasound evaluation of the ilioinguinal nerve, an imaginary line is drawn between the anterior superior iliac spine and the patient’s umbilicus. Oblique placement of the ultrasound transducer placed in a plane perpendicular with the inguinal ligament with the inferior aspect of the transducer lying over the anterior superior iliac spine and the superior aspect of the transducer pointed directly at the umbilicus. Oblique ultrasound image demonstrating the hyperechoic anterior superior iliac spine and its acoustic shadow and the external oblique, internal oblique, and transversus abdominis muscles. Note fascial plane between the internal oblique and transversus abdominis muscles. Oblique ultrasound image demonstrating the ilioinguinal nerve lying within the fascial plane between the internal oblique and transversus abdominis muscles. The ilioinguinal nerve and iliohypogastric nerve both lie in the fascial plane between the internal oblique and transversus abdominis muscles. Color Doppler image demonstrating the deep circumflex iliac artery, which lies in the fascial plane between the internal oblique and transversus abdominis muscles adjacent to the ilioinguinal nerve. It should be remembered that pathology affecting the lumbar plexus may mimic the clinical presentation of ilioinguinal neuralgia and should be considered in all patients presenting with groin pain in the absence of trauma to the region (Fig. The nerve exits the lateral border of the psoas muscle to follow a curvilinear course that takes it from its origin of the L1 and occasionally T12 somatic nerves to inside the concavity of the ilium (Fig. The iliohypogastric nerve continues in an anterior trajectory as it runs between the layers of the internal oblique and transverse abdominis muscles along with the ilioinguinal nerve and deep circumflex iliac artery (Fig. It is at this point that it is the nerve can consistently be identified with ultrasound scanning and is amenable to ultrasound-guided nerve block (Fig. Within the fascial plane between the internal oblique and transversus abdominis muscles, the iliohypogastric nerve divides into an anterior and a lateral branch (Figs. The lateral branch provides cutaneous sensory innervation to the posterolateral gluteal region. The anterior branch pierces the external oblique muscle just beyond the anterior-superior iliac spine to provide cutaneous sensory innervation to the abdominal skin above the pubis. The distribution of the sensory innervation of the iliohypogastric nerves varies from patient to patient due to considerable overlap with the ilioinguinal nerve. In most patients, the anterior branch of the iliohypogastric nerve provides sensory innervation to the skin overlying the pubis, with the lateral branch is providing sensory innervation to the skin overlying posteriolateral gluteal region (Fig. The ilioinguinal nerve exits the lateral border of the psoas muscle to follow a curvilinear course that takes it from its origin of the L1 and occasionally T12 somatic nerves to inside the concavity of the ilium. The ilioinguinal nerve continues in an anterior trajectory as it runs between the layers of the internal oblique and transverse abdominius muscles. Oblique ultrasound image demonstrating the hyperechoic anterior-superior iliac spine and its acoustic shadow and the external oblique, internal oblique, and transversus abdominus muscles. Note fascial plane between the internal oblique and transversus abdominis muscles. Red stars indicate the ilioinguinal and iliohypogastric nerves (furthest from the anterior-superior iliac spine) lying within the fascial plane. The anatomic relationship of the ilioinguinal and iliohypogastric nerve as they pass within the fascial plane between the internal oblique and transverse abdominis muscles. Less commonly, iliohypogastric neuralgia can be seen in patients in their third trimester of pregnancy when a rapidly expanding abdomen causes a traction neuropathy of the nerve. The symptoms associated with ilioinguinal neuralgia depend on whether the main trunk of the nerve is damaged or if the injury is isolated to the anterior or the lateral branch of the nerve (Fig. If the injury is isolated to the anterior branch of the iliohypogastric nerve, the patient will complain of burning pain, 690 paresthesias, and numbness in the skin overlying the pubis. If the lateral branch is damaged, the patient will complain of burning pain, paresthesias, and numbness in the skin overlying posterior–lateral gluteal region. Tinels sign may be elicited by tapping over the iliohypogastric nerve at the point where it pierces the transversus abdominis muscle. Ultrasound-guided iliohypogastric nerve block can be employed as a diagnostic maneuver when performing differential neural blockade on an anatomic basis to determine if the patient’s lower abdominal and groin pain are subserved by the iliohypogastric nerve (Fig. If destruction of the iliohypogastric nerve is being contemplated, ultrasound-guided iliohypogastric nerve block with local anesthetic can provide prognostic information as to the extent of motor and sensory deficit the patient will experience following nerve destruction. Electromyography can distinguish iliohypogastric nerve entrapment from lumbar plexopathy, lumbar radiculopathy, and diabetic polyneuropathy. Plain radiographs of the hip and pelvis are indicated in all patients who present with iliohypogastric neuralgia to rule out occult bony pathology. Based on the patient’s clinical presentation, additional testing may be warranted, including a complete blood count, uric acid level, erythrocyte sedimentation rate, and antinuclear antibody testing. Magnetic resonance imaging of the lumbar plexus and retroperitoneum is indicated if tumor or hematoma is suspected (Fig. Ultrasound-guided iliohypogastric nerve block can be employed as a diagnostic maneuver when performing differential neural blockade on an anatomic basis to determine if the patient’s lower abdominal and groin pain are subserved by the iliohypogastric nerve. If destruction of the iliohypogastric nerve is being contemplated, ultrasound-guided iliohypogastric nerve block with local anesthetic can provide prognostic information as to the extent of motor and sensory deficit the patient will experience following nerve destruction. The umbilicus, anterior-superior iliac spine, and inguinal ligament are identified by visual inspection and palpation and an imaginary line is drawn between the anterior-superior iliac spine and the umbilicus (Fig. A linear high-frequency ultrasound transducer is placed in a plane perpendicular with the inguinal ligament with the inferior aspect of the transducer lying over the anterior-superior iliac spine and the superior aspect of the transducer pointed directly at the umbilicus and an ultrasound survey scan is obtained (Fig. The hyperechoic anterior-superior iliac spine and its acoustic shadow are identified as are the external oblique, internal oblique, and transversus abdominus muscles which extend outward from it (Fig. The fascial plane between the internal oblique and transversus abdominis muscles are then identified and the iliohypogastric nerve should be easily identifiable as an ovoid hypoechoic structure highlighted by a hyperechoic epineurium lying more medial in relation to the anterior-superior iliac spine as compared to the ilioinguinal nerve which lies closer to the anterior-superior iliac spine (Fig.
Measuring Oxygenation Clinically mild hypoxia up to hemoglobin saturation of 75% is difficult to detect and various investigation are helpful in early identification and regular monitoring of Oxygenation status discount rizatriptan 10mg mastercard. Abnormal Hb like Methemoglobinemia purchase 10 mg rizatriptan free shipping, Carboxyhemoglobin can be missed unless correlated with pulse oxymetry (Here SpO2 is low and PaO2 is normal) generic 10 mg rizatriptan with amex. Pulse Oxymeter It determines hemoglobin oxygen saturation (SpO2), which follows S shape curve (Fig. Drawbacks of SpO2 • Hyperoxia cannot be identified since 100 PaO2 and 500 PaO2 both will have same oxygen saturation (SpO2) of 99-100%. Precautions • Pulse oxymeter should be calibrated periodically so as to avoid mistakes while treating a critical patient. In the normal respiratory tract, inhaled gases are humidified to 100% relative humidity. Artificial airways like the endotracheal tube or tracheostomy tube may bypass 25% of the humidification area. So a simple humidifier without heating capacity can be used in patients without artificial airways. Monitoring temperature and humidity while oxygen delivery is desirable which can be optimally done by heating wires in the breathing tubes. Nebulizers in their droplets of water increases the potential of infection, specially when given through artificial, devices so should best be avoided. Since flow is high and may pass the humidifying surfaces quickly, humidification is required. Oxygen Sources and Flow Regulators Medical gas is provided from either a wall source or a cylinder. This is too much for any patient or ventilator and hence a down regulating valve is needed before the flow- meter attachment. Low Flow Devices Nasal cannula: 2 soft prongs that enter the nostrils, attached to an oxygen source by a fairly long tube. It will provide low FiO2 between 30–40% (fitting a nasal cannula in a neonate will provide almost 90% FiO2 at 1 lit/min). Since humidifying mucosa is not bypassed and flow is less, humidification is not required. Flow in this system is less than minute volume so air mixing continues and precise FiO2 can’t be adjusted. It fits the face without much discomfort and is often loose enough to allow entry of room air hence the FiO2 is not very high. Precise FiO2 is not the aim when using these masks and they are not to be used for conditions of hypoxemia. Partial rebreathing masks: These are simple masks with an additional reservoir that allows the accumulation of oxygen enriched gas for rebreathing. Upto 60% FiO2 can be delivered but the pitfalls are similar to those of a simple mask. Non-rebreathing masks: These look similar to the rebreathing mask but have a valve that allows only O2 from the source to enter the reservoir and exhaled air does not enter. High Flow Devices 6-10 lit/min –Venturi, non-rebreathing masks, under tent high flow, etc. Non-rebreathing masks: These are like the above masks, but have a valve at the exhalation port that allows only exhaled gases to enter the reservoir. There are openings (entrainment ports) near the nozzle that allow room air to be sucked in, diluting the oxygen. Changing the size of the nozzle, the flow rates, as well as ports, allows control of the amount of oxygen. The advantages of a venturi system include: (i) A high flow device guarantees the delivery of a fixed FiO2; (ii) the high flow comes from the air therefore saving on oxygen costs; (iii) Can be used for low FiO2also; (iv) Helps in deciding whether the oxygen requirement is really increasing or decreasing; (v) Humidification not needed; and (vi) Fairly cheap and reliable. The average infant or even toddler is usually intolerant of a mask and will keep pulling it off. In fact, the infant that remains quiet when the mask is first fitted, is one that may be obtunded from hypoxia or too tired too fight. A clear transparent hood that has enough room for the baby’s head to fit comfortably and allows free neck and head movement without hurting the baby, is the correct hood size to use. Too big a hood will dilute the oxygen and too small a hood will cause discomfort and result in carbon dioxide accumulation. Adequate flow of humidified oxygen ensures mixing of delivered gases and flushing out of carbon dioxide. Cold air will cause heat stress and condense on the baby’s head, which will be mistaken for perspiration. Measurement of Delivered Oxygen: An oxymeter or FiO2 meter is used to measure the concentration of oxygen actually delivered to the patient. The important part of this system is the actual sensor it’s quality and accuracy is of paramount importance. It is connected to an instrument that digitally converts the sensed concentration into a reading that is displayed. It also tells us how wrong our own rough estimates of delivered oxygen can often be. The oxyhood is the ideal place to use it but it can also be held at the mouth/nose within a mask for a quick reading. This is the classic criterion but it must be stressed that clinical parameters and the general conditions of the patient must also act as a guiding force. Whatever the method of delivery, it is a versatile tool in the child with early, incipient or even frank respiratory failure. There are several comfortable prongs available and the cheapest are the plastic oxygen cannula. It should be tried prior to conventional ventilation in any spontaneously breathing patient who does not require emergency ventilation. Oxygen Concentrator: This device separates oxygen from nitrogen in the air by using adsorption and desorption over a material called zeolite, that adsorbs only the nitrogen. This diseases the plasma, partial pressure and the dissociation occurs in the plasma rather than from that bound to hemoglobin.