RESUSCITATION EQUIPMENT

To ensure that resuscitation proceeds without difficulty, the whereabouts and function of all resuscitation equipment must be known by those responsible for resuscitating the neonate before the birth occurs.

The resuscitation bed should tilt to permit the neonate's head to be positioned below the level of the body. This promotes drainage of lung fluid and reduces the likelihood of aspiration of gastric contents. A servo-controlled infrared heater should be used to maintain the neonate's axillary temperature between 36°C and 37°C. A suction device should be included, and the person

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Figure 59-4 A modified Ayres T-piece that allows positive end-expiratory pressure and has a "pop-off" to reduce the likelihood of a pneumothorax. (Adapted from Gregory GA, Kitterman JA, Phibbs RH, et al: Treatment of the idiopathic respiratory-distress syndrome with continuous positive airway pressure. N Engl J Med 284:1333, 1971.)

The equipment required for tracheal intubation includes 0 and 00 straight laryngoscope blades; a pencil-type laryngoscope handle; 2.5-, 3.0-, and 3.5-mm Magill-type endotracheal tubes; and a suction catheter that easily fits through each size of endotracheal tube.

The ventilation system used for resuscitation must permit a positive end-expiratory pressure (PEEP) and ventilatory rates of at least 150 breaths/min to be maintained. The system should not include one-way valves because they can stick in the closed position, especially when high gas flows and high respiratory rates are used. If the valve sticks, the patient may develop a pneumothorax. The modified Jackson-Rees or Ayres system shown in Figure 59-4 works well for neonatal resuscitation if people are appropriately trained in its use. This device permits controlled ventilation at rapid respiratory rates and maintenance of PEEP. It also has a "pop-off" to reduce the likelihood of creating a pneumothorax. This ventilation system has no valves. The use of Ambu bags may be less effective because the valves can stick closed, it is more difficult to deliver 100% oxygen, and it is not possible to maintain a PEEP with these devices. The latter is important when resuscitating neonates who have atelectasis. Airway pressures should be measured during resuscitation, usually by attaching a pressure manometer to the resuscitation device. Care must be taken not to overexpand the lungs because overexpansion of the lungs (i.e., large tidal volumes) is the primary cause of lung injury.^[52] Overexpansion of the lung initiates an inflammatory process that may lead to chronic lung disease in neonates.^[8] Gentle inflation of the lung is less injurious to the lung. When we are frightened (as we usually are) while resuscitating neonates, it is easy to overinflate and damage the lungs of neonates. Airway inflation pressures should be measured continuously during assisted or controlled ventilation in the delivery room, because excessive airway pressures can cause excessive tidal volumes.

As in any intensive care situation, patient care should be guided by information. Consequently, blood gas and pH measurements are mandatory, and the results of these tests must be available within 10 minutes of drawing the blood sample. Umbilical arterial catheters permit people doing the resuscitation to measure arterial blood pressure, withdraw blood for blood gas and pHa determinations, and infuse fluids.

Oxygen sensor-containing catheters can be used for resuscitation. Because the response time of these catheters is 10 to 15 seconds, the effectiveness of resuscitation efforts in improving oxygenation can be readily ascertained ( Fig. 59-5 ). Although oxygenation can also be measured transcutaneously, these electrodes take 15 minutes to stabilize after being applied to the skin. The values only correlate with PaO₂ when the blood pressure is normal and the body temperature is above 35.5°C.^[53] Arterial oxygen saturation (SaO₂ ) should be measured immediately after birth with a pulse oximeter that is applied to a hand or foot.^[54] These devices give good estimates of SaO₂ when the patient's condition is stable but

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Figure 59-5 Relationships among ventilation, oxygen saturation (SaO₂ ), arterial partial pressure of oxygen (PaO₂ ), and inspired oxygen concentration (FIO₂ ) during neonatal resuscitation. CPAP, continuous positive airway pressure.

Needle electrodes inserted under the skin provide continuous electrocardiograms and heart rate values. Two pressure transducers are required to measure arterial and central venous pressures. Monitors used in neonatal intensive care units are adequate for use during resuscitation.