Essential Factors of Labor (5 P's of Labor) PDF

BATAAN PENINSULA STATE UNIVERSITY COLLEGE OF NURSING AND MIDWIFERY City of Balanga 2100 Bataan PHILIPPINES...

BATAAN PENINSULA STATE UNIVERSITY COLLEGE OF NURSING AND MIDWIFERY City of Balanga 2100 Bataan PHILIPPINES Essential Factors of Labor (5 P’s of Labor) PASSAGE, PASSENGER, PERSON, POWER, POSITION I. PASSAGE - Refers to the route that the fetus must travel from the uterus through the cervix and vagina to the external perineum. Because the cervix and vagina are contained inside the pelvis, the fetus must also pass through the bony pelvic ring. The passage consists of the bony pelvis (composed of the sacrum, ilium, ischium, and pubis) and the resistance provided by the soft tissues. PARTS OF THE PELVIS A. Innominate bones 1. Ilium- forms the upper and lateral portion of the pelvis Iliac crest- upper flaring portion that forms the prominence of the hips 2. Ischium- Inferior portion Ischial tuberosities- two projections, portion of one where the person sits, used to determine lower pelvic width. Ischial spines- small projections that extend from lateral aspect into the pelvic cavity, marks the midpoint of pelvis 3. Pubis- Anterior of innominate bones. Symphysis pubis- junction of innominate bones at the front of pelvis B. Sacrum- forms the upper posterior portion of pelvic ring Sacral Prominence- marked anterior portion of this bone at the point where it touches the lower lumbar vertebrae. C. Coccyx- found below the sacrum, composed of five very small bones fused together Sacrococcygeal joint- between sacrum and coccyx, allows for some degree of movement to allow passage of fetal head. PELVIS – bony ring formed from four united bones Functions: 1. Protection to organ within the pelvic cavity 2. Attachment to muscles, fascia, and ligaments 3. Supports uterus during pregnancy 4. Serves as birth canal FOR OBSTETRIC PURPOSES PELVIS IS DIVIDED TO: A. False pelvis- Supports uterus during the last months of pregnancy and aids in directing the fetus into the true pelvis for birth B. Linea Terminalis (pelvic brim, ileopectineal line) − An imaginary line that divides true and false pelvis − Drawn from sacral prominence to the superior aspect of the symphysis pubis C. True pelvis 1. Pelvic Inlet- Upper ring of bone through which fetus must pass to be born vaginally Wider transversely and narrow in anteroposterior aspect of symphysis pubis a. Anteroposterior diameter − Diagonal Conjugate - The distance between the anterior surface of sacral prominence and the inferior margin of symphysis pubis - It is the most useful pelvic measurement because it’s the one that is most apt to cause misfit with the fetal head - Normal is 10.5-11cm or more which means that a mother has adequate pelvis - It is measured by the middle finger touching the sacral prominence and the other hand marks the part of examining hand that touches the symphysis pubis and comparing it VISION MISSION A leading univerity in the Philippines recognized for its To develop competitive graduates and empowered community members by providing relevant, proactive contribution to Sustainable Development through innovative and transformative knowledge, research, extension and production programs and services equitable inclusive programs and services by 2030. through progressive enhancement of its human resource capabilities and institutional mechanism.  to pelvimeter. − Obstetric Conjugate - The distance between the midpoint of the sacral promontory and the midpoint of symphysis pubis - Normal measurement is approximately 11cm − True Conjugate (Conjugata Vera) - The distance between anterior surface of sacral prominence and anterior surface of the superior margin of the symphysis pubis - Its normal measurement cannot be done directly, but through subtracting 1.2-2cm from diagonal conjugate True Conjugate = Diagonal conjugate (12.5cm) minus the usual depth of symphysis pubis (1.5-2cm) * Normal measurement is approximately 10.5-11cm b. Transverse diameter - 13.5 cm c. Right Oblique Diameter - 12.75cm d. Left Oblique Diameter - 12.75cm 2. Pelvic Canal / Pelvic Cavity - The space between inlet and outlet, a CURVED and SNUG passage. CURVED- because it slows / controls the speed of birth and therefore reduces sudden pressure increase in fetal head which might rupture cerebral arteries SNUG- compress the chest of fetus as she/he passes through, helping to expel lung fluid and mucus thereby better prepare the lungs for good aeration at birth ISCHIAL SPINES- landmark used for assessing of fetal descent and engagement a. AP diameter - 11.5cm b. Posterior sagittal diameter - 4.5cm c. Interspinous diameter - 10cm 3. Pelvic Outlet- Inferior portion of pelvis is bounded by: Coccyx at the back, ischial tuberosities at the sides, and symphysis pubis in inferior aspect in the front. a. AP diameter - 9.5-11cm b. Posterior sagittal diameter - 7.5cm c. Bi-ischial diameter - the distance between two ischial tuberosities 11.5cm, can be cause of misfit with the fetal head CONTRACTED PELVIS - Refers to a pelvis with measurement less than 1.5-2 cm on any of its diameter and therefore makes vaginal delivery not possible PELVIC ARTICULATION - joints of pelvis EFFECTS OF HORMONES - progesterone and relaxin causes increase joint and bone mobility Kinds of Pelvis A. Android - “male” pelvis. Inlet has narrow, shallow posterior portion & pointed anterior portion - Heart-shaped - Convergent sidewalls - Prominent ischial spines - Narrow pubic arch B. Anthropoid - transverse diameter is narrow, AP diameter is larger than normal. - Oval-shaped - AP diameter more than transverse diameter - Wide sidewalls C. Gynecoid - “normal” female pelvis. Inlet is well rounded forward & back. Most ideal for childbirth. - 50% of women - Equal AP & T diameter - Straight pelvic sidewalls - Non-prominent ischial spines - Wide pubic arch D. Platypelloid - inlet is oval, AP diameter is shallow - Transverse diameter more than AP diameter - Wide sidewalls NRCM0107 LECTURE 2 II. PASSENGER – Being the largest part of the fetal body, the head is the part that would most likely encounter difficulty during delivery. A. Structures of the fetal skull 1. Eight Bones of the Cranium a. Four Superior Bones - One Frontal - Two Parietal - One Occipital b. Other Four Bones - Two Temporal - One Sphenoid - One Ethmoid c. Chin 2. Suture lines – The fetal skull is not yet completely ossified at birth and its bones are joined only by membranes so that spaces actually exist between them. These spaces are called suture lines or suture. a. Sagittal Suture – located between 2 parietal bones b. Coronal Suture - located between frontal and parietal bones c. Lambdoidal Suture - located between parietal and occipital bones 3. Fontanelles – membrane covered spaces located between the intersections of suture lines. a. Anterior Fontanelle – formed by the intersection of the sagittal, frontal and coronal sutures, diamond shaped, closes between 12-18 months of age. b. Posterior Fontanelle - formed by the intersection of the sagittal and lambdoidal sutures, triangular in shape, closes by 2-3 months of age. B. Diameters of Fetal skull 1. Suboccipitobregmatic diameter - Smallest AP diameter - Head is fully flexed - Measured from the inferior aspect of occiput to the anterior fontanel - Average size - 9.5 cm. 2. Suboccipito-frontal Diameter - Measured from - Head is partially deflexed - Average size - 10.5 cm. 3. Occipitofrontal Diameter - Head is deflexed - Presenting part is the anterior fontanel - Measured from bridge of the nose to occipital prominence - Average size – 11.5 cm. 4. Mento-vertical diameter - Head is partially extended - Presenting part is brow - Measured from chin to the vertical point - Average size – 13.5 cm. - Longer than the largest diameter of the pelvic brim, the head cannot enter the pelvis. 5. Submento-bregmatic diameter - Head is completely extended - Presenting part is face - Measured from chin to anterior fontanel - Average size – 9.5 cm. C. Molding overlapping of the skull bones during delivery in order to reduce the size of the fetal head. D. Fetal Presentation and Position 1. Attitude a. Good Attitude b. Moderate Flexion c. Partial Extension NRCM0107 LECTURE 3  d. Complete Extension 2. Engagement Floating – head is movable above pelvic inlet Dipping – 3. Station – relationship of the presenting part of the fetus to an imaginary line drawn at the level of the ischial spines of the mother. 4. Fetal lie – Refers to the relationship between the long axis of the fetus with respect to the long axis of the mother. a. Transverse – the long axis of the fetus is not lying along the long axis of the mother. b. Longitudinal – (may be either cephalic or breech) is Normal. c. Oblique – the fetal long axis is at an angle to the bony inlet, and no palpable fetal part generally is presenting. E. Types of Fetal Presentation 1. Cephalic presentation a. Vertex b. Sinciput c. Brow d. Face CAPUT SUCCEDANEUM – refers to swelling, or edema, of an infant's scalp that appears as a lump or bump on their head shortly after delivery. This condition is harmless and is due to pressure put on the infant's head during delivery. 2. Breech Presentation a. Complete b. Incomplete c. Frank d. Footling 3. Shoulder Presentation Three Causes: a. Relaxed abdominal walls due to grand multiparity b. Pelvic contraction c. Placenta previa 4. Compound Presentation F. Types of fetal Position 1. Left Occiput Anterior 2. Right Occiput Anterior 3. Left Occiput Posterior 4. Right Occiput Posterior 5. Occiput Anterior 6. Occiput Posterior 7. Left Occiput Transverse 8. Right Occiput Transverse G. Mechanism/Cardinal Movements of Labor 1. Descent 2. Flexion 3. Internal Rotation 4. Extension 5. External Rotation 6. Expulsion III. POWER Primary Force is the uterine contractions. Secondary Force is the bearing down efforts of the mother Cervical Changes 1. Effacement 2. Dilatation IV. PERSON / PSYCHE OR ATTITUDE – The attitude of the mother during labor process and outcome. The progress of labor and birth can be adversely affected maternal fear and tension. NRCM0107 LECTURE 4  Anxiety can also increase pain perception and lead to an increased need for analgesia & anesthesia. Psychosocial Considerations − Social support − Past experience − Knowledge V. POSITION of mother during delivery Anesthesia, if indicated, is administered first before the woman is made to assume the delivery position. 1. Lithotomy Position 2. Dorsal Recumbent – With the head inclined at 15-30˚ angle. 3. Side-lying Position 4. Squatting position NRCM0107 LECTURE 5