Resuscitating the Baby after Shoulder Dystocia

Cardiac Asystole at Birth Re-Visited: Effects of Acute Hypovolemic Shock

Births involving shoulder dystocia or tight nuchal cords can deteriorate rapidly. The fetus may have had a reassuring tracing just before birth yet may be born without any heartbeat (asystole). Since the publication of our first article on cardiac asystole with two cases, five similar cases have been published. We suggest that these infants shift blood to the placenta due to the tight squeeze of the birth canal during the second stage which compresses the cord. The squeeze transfers blood to the placenta via the firm-walled arteries but prevents blood returning to the infant via the soft-walled umbilical vein. These infants may then be born severely hypovolemic resulting in asystole secondary to the loss of blood. Immediate cord clamping (ICC) prevents the newborn's access to this blood after birth. Even if the infant is resuscitated, loss of this large amount of blood volume may initiate an inflammatory response that can enhance neuropathologic processes including seizures, hypoxic-ischemic encephalopathy (HIE), and death. We present the role of the autonomic nervous system in the development of asystole and suggest an alternative algorithm to address the need to provide these infants intact cord resuscitation. Leaving the cord intact (allowing for return of the umbilical cord circulation) for several minutes after birth may allow most of the sequestered blood to return to the infant. Umbilical cord milking may return enough of the blood volume to restart the heart but there are likely reparative functions that are carried out by the placenta during the continued neonatal-placental circulation allowed by an intact cord.

Resuscitation of Term Compromised and Asphyctic Newborns: Better with Intact Umbilical Cord?

The authors hypothesize that particularly severely compromised and asphyctic term infants in need of resuscitation may benefit from delayed umbilical cord clamping (after several minutes). Although evidence is sparse, the underlying pathophysiological mechanisms support this assumption. For this review the authors have analyzed the available research. Based on these data they conclude that it may be unfavorable to immediately clamp the cord of asphyctic newborns (e.g., after shoulder dystocia) although recommended in current guidelines to provide quick neonatological support. Compression of the umbilical cord or thorax obstructs venous flow to the fetus more than arterial flow to the placenta. The fetus is consequently cut off from a supply of oxygenated, venous blood. This may cause not only hypoxemia and consecutive hypoxia during delivery but possibly also hypovolemia. Immediate cord clamping may aggravate the situation of the already compromised newborn, particularly if the cord is cut before the lungs are ventilated. By contrast, delayed cord clamping leads to fetoplacental transfusion of oxygenated venous blood, which may buffer an existing acidosis. Furthermore, it may enhance blood volume by up to 20%, leading to higher levels of various blood components, such as red and white blood cells, thrombocytes, mesenchymal stem cells, immunoglobulins, and iron. In addition, the resulting increase in pulmonary perfusion may compensate for an existing hypoxemia or hypoxia. Early cord clamping before lung perfusion reduces the preload of the left ventricle and hinders the establishment of sufficient circulation. Animal models and clinical trials support this opinion. The authors raise the question whether it would be better to resuscitate compromised newborns with intact umbilical cords. Obstetric and neonatal teams need to work even closer together to improve neonatal outcomes.

Making the Argument for Intact Cord Resuscitation: A Case Report and Discussion

We use a case of intact cord resuscitation to argue for the beneficial effects of an enhanced blood volume from placental transfusion for newborns needing resuscitation. We propose that intact cord resuscitation supports the process of physiologic neonatal transition, especially for many of those newborns appearing moribund. Transfer of the residual blood in the placenta provides the neonate with valuable access to otherwise lost blood volume while changing from placental respiration to breathing air. Our hypothesis is that the enhanced blood flow from placental transfusion initiates mechanical and chemical forces that directly, and indirectly through the vagus nerve, cause vasodilatation in the lung. Pulmonary vascular resistance is thereby reduced and facilitates the important increased entry of blood into the alveolar capillaries before breathing commences. In the presented case, enhanced perfusion to the brain by way of an intact cord likely led to regained consciousness, initiation of breathing, and return of tone and reflexes minutes after birth. Paramount to our hypothesis is the importance of keeping the umbilical cord circulation intact during the first several minutes of life to accommodate physiologic neonatal transition for all newborns and especially for those most compromised infants.

Cord Management of the Term Newborn

Keeping the umbilical cord intact after delivery facilitates transition from fetal to neonatal circulation and allows a placental transfusion of a considerable amount of blood. A delay of at least 3 minutes improves neurodevelopmental outcomes in term infants. Although regarded as common sense and practiced by many midwives, implementation of delayed cord clamping into practice has been unduly slow, partly because of beliefs regarding theoretic risks of jaundice and lack of understanding regarding the long-term benefits. This article provides arguments for delaying cord clamping for a minimum of 3 minutes.

Favorable outcome after nine minutes of shoulder dystocia preceded by a tight nuchal cord

Objectives

A case report involving a tight nuchal cord and concomitant shoulder dystocia with a review of the literature. We demonstrate that favorable outcomes may result with correct application of maneuvers and adequate management after delivery.

Case presentation

A 41 years old woman was admitted with spontaneous rupture of membranes. The first stage of labor was unremarkable. During the second stage, an intentionally-cut tight nuchal cord was followed by 9 min of shoulder dystocia that was finally relieved by delivery of the anterior shoulder. APGAR scores were 0, 3, 4, 7 at 1, 5, 10 and 20 min respectively. The neonate was placed under therapuetic hypothermia and was discharged after 13 days. At 5 months and 1.5 years of age, the infant met age appropriate developmental milestones with no neurologic sequela.

Conclusions

Shoulder dystocia can result in fatal outcomes for the neonate. Adequate management highlights the need for prompt recognition of this complication and application of appropriate maneuvers. Therapeutic hypothermia decreases mortality and improves neurological development in infants who experience hypoxic ischemic encephalopathy (HIE).

Intrapartum Asphyxiated Newborns Without Fetal Heart Rate and Cord Blood Gases Abnormalities: Two Case Reports of Shoulder Dystocia to Reflect Upon

Our report covers two cases of severe hypoxic-ischemic encephalopathy in newborns whose birth was complicated by shoulder dystocia. In both cases, there were inconsistencies observed among cardiotocographic traces, baby's clinical conditions at birth, and umbilical cord blood gases. Namely, normal cardiotocographic monitoring and cord pH > 7, in spite of the fact that the newborns were severely depressed at birth and their blood gases evaluated within 1 h from birth showed a severe metabolic acidosis. Moreover, one of the two newborns displayed moderately low hemoglobin levels. Metabolic and infectious causes were ruled out. Both newborns developed severe hypoxic-ischemic encephalopathy and received therapeutic hypothermia for 72 h. Both survived, one with a severe dystonic cerebral palsy whereas the other developed only a mild developmental delay in language. Cardiac asystole theory could explain these two cases, reinforcing the need for specific resuscitation guidelines for infants experiencing a birth complicated by shoulder dystocia.

Placental Transfusion for Asphyxiated Infants

The current recommendation for umbilical cord management of non-vigorous infants (limp, pale, and not breathing) who need resuscitation at birth is to immediately clamp the umbilical cord. This recommendation is due in part to insufficient evidence for delayed cord clamping (DCC) or umbilical cord milking (UCM). These methods may provide a neuroprotective mechanism that also facilitates cardiovascular transition for non-vigorous infants at birth.

Umbilical Cord Milking: A Review

This is a review of umbilical cord milking, a controversial technique where the umbilical cord is squeezed several times before it is clamped an cut. While not physiological or natural for newborns, the question lies as to whether it is useful in certain circumstances, namely the depressed newborn. Here we review the literature and discuss why it could be considered as an alternative for the current practice of delayed cord clamping.

Shoulder dystocia: incidence, mechanisms, and management strategies

Shoulder dystocia can lead to death or brain damage for the baby. Traction on the head can damage the brachial plexus. The diagnosis should be made when the mother cannot push the shoulders out with her own efforts with the next contraction after delivery of the head. There should be no traction on the head to diagnose shoulder dystocia. McRoberts’ position is acceptable but it should not be accompanied by any traction on the head. If the posterior shoulder is in the sacral hollow then the best approach is to use posterior axillary traction to deliver the posterior shoulder and arm. If both shoulders are above the pelvic brim, the posterior arm should be brought down with Jacquemier’s maneuver. If that fails, cephalic replacement or symphysiotomy is the next step. After shoulder dystocia is resolved, one should wait 1 minute or so to allow placental blood to return to the baby before cutting the umbilical cord.