What are the “normal” neonatal vital signs and how do we assess them?
In general, the vital signs we monitor in the NICU are:
Heart Rate
Respiratory Rate
Temperature
Oxygen Saturation
Blood Pressure
Pain
These vitals are taken every hour. However, if a baby is on certain medications (ex: Dopamine), vital signs may need to be taken more frequently (e.g. every 15 minutes).
General NICU Vital Ranges:
Heart Rate: 100-200
Respiratory Rate: 10-100
Temperature: 36.5 C—37.5 C
Oxygen Sats:
< 34 weeks gestation: Target range: 86-92% & Monitor alarm limits: 84-94%
> 34 weeks gestation: Target range: 88-94% & Monitor alarm limits: 86-96%
Note: The upper alarm limit is d/c’d if the infant is on room air (FiO2 21%).
5. Blood Pressure (depends on gestation):
<24 weeks gestation: Systolic 50-65. Diastolic 24-40. MAP 24-30.
24-28 weeks gestation: Systolic 50-60. Diastolic 22-35. MAP 24-35.
29-32 weeks gestation: Systolic 50-60. Diastolic 24-35. MAP 30-40.
32-36 weeks gestation: Systolic 50-60. Diastolic 24-35. MAP 30-50.
>36 weeks gestation: Systolic 50-90. Diastolic 28-40. MAP 35-45.
Note: Premature infants <30 weeks gestation/corrected age receive an additional point on this scale due to their inability to effectively convey their pain.
NICU MEDICAL EQUIPMENT used to assess vital signs:
1. MONITORS
Various monitors are used in the NICU to provide information in numerical and waveform formats.
2. EKG LEADS
Heart rate, respirations, and pulse are monitored with 3 lead EKG stickies that are placed over the chest and belly. In most cases, a 12-lead EKG is not used on neonates because of the limited size of their bodies.
3. THERMOMETER
Temperatures are usually taken via axillary (armpit). If a baby is in an isolette, a skin probe (attached to the baby) displays the baby’s temperature. This is how we keep them nice and toasty. We do not want our babies to experience cold stress.
4. PULSE OX PROBE
A pulse ox probe (attached to hand, wrist, or foot) monitors the oxygen saturation. We place this probe on the furthest point away from the heart to see how well the heart can perfuse the entire body. If the extremities are well oxygenated, that means the core must also be.
Blood pressure cuffs are based on weight. Parents love saving the different size cuffs that their babies have outgrown. It’s a fun little keepsake and memento for scrapbooks. In newborns and micropreemies, umbilical arterial lines (UACs) can be used to obtain blood pressures. This catheter is constantly analyzing the infant’s blood pressure and populates it on the monitor. This avoids unnecessary squeezing of the extremities and sleep disturbances during the most critical time of the newborn’s life.
Pain is scored every 3-4 hours with some form of a standard pain scale. “N-PASS” is the most commonly used tool.
As you can see, each vital sign varies depending on how many weeks gestation the baby was born and is currently corrected. Even just a few days/weeks difference changes the way we program the monitors and what the normal ranges look like. For example, a micropreemie will typically display higher heart rates, irregular breathing patterns, fluctuating temperatures depending on his/her environment, oxygen saturations with lower thresholds, and will exhibit higher pain scores. Gestational age is SO important and plays a HUGE factor when it comes to vital signs!