Small Ani. Sx- Diaphragmatic Hernias

wilsbach's version from 2015-11-04 19:27

intro and D. hernia

Question Answer
what is Bdays big soapbox about D. hernias?not true hernia bc no perineal lining
in a D. hernia, where does the diaphragm usually break?on VENTRAL aspect usu
definition of a D. herniacontinuity of the diaphragm is disrupted leading to protrusion of the abdominal viscera through the diaphragm into the thoracic cavity
2 types of etiology of a D. hernia?Congenital, or Acquired (traumatic) (**more commonly traumatic)
The cupula of the diaphragm can extend to what ICS?8th (the cupula is the reflection of the plura against the diaphram back up the sides of the walls (red line)
what are the three different kinds of D. hernias (based on how the tears are) how common is each? Radial, circumferential, combined. Radial is most common > combined >circumferential
where does a radial D hernia happen?costal insertion up to center tendinosus. most common
where does a circumferential hernia happen?parallel up to ribs.
what are the three types of congenital hernias?(1) pleuroperitoneal (2) peritoneo-pericardial (3) hiatal
which congenital hernia is sometimes associated with ventral hernias?peritoneo-pericardial
what is more common- congenital or traumatic hernias?Traumatic hernias are 93% of the hernias!
which side of the body do pleuroperitoneal hernias usually happen? (why?)Left (Bc liver abutting on right I think he said?)
Clinical signs of a traumatic D. herniadyspnea (if more severe, resp. sounds), tachypnea, cyanosis, orthopnea (short of breath when laying down), muffled heart sounds, borborygmus, careful w’ thin patients (can be GI that's just up high near diaphragm), vomiting, chronic cough, exercise intolerance, tucked-up abdomen, postprandial respiratory difficulty, anorexia
what are two general things you should know about using clinical signs to dx a d hernia?*Signs may be intermittent or absent *Signs are not pathognomonic
If stomach passes through herniation, what might happen?true ER- when stomach passes through diaphragmatic hole- dies. coughing- may aspirate
if small intestine passes through herniation, what might happen?small bowel often passes through- doesnt tend to cause adherence w/ other organs
if liver passes through herniation, what might happen?capsule can extrude fibrin and cause adhesions
what are some things he mentioned of how the thorax is affected by the herniation? Ex of when it might be best to NOT operate?hepatiziation of lungs due to being squished. electric axis of heart is shifted (bc heart pushed out of place). other lung that's not squished tries to compensate. sometimes not best to operate if disturbing quiet organs or abd isnt big enough to replace viscera
when might you wanna use fluoroscopy?to try to dx hiatal hernia
two types (locations) of contrast studies you can use to dx D hernias?GI transit, intra-peritoneal
4 radiographic signs of a traumatic D hernia?(1) Interruption of diaphragmatic outline (2) Soft tissue density in thorax (3) Gas-filled viscera in thorax (4) Loss of cardiac silhouette
3 auscultation oddities/ abnormalities which might indicate a D hernia(1) muffled heart and respiratory sounds - indicates fluid or viscera in pleural space (2) borborygmus - intestines in pleural space (3) tympany on left side of thorax - stomach in pleural space
sx repair of hernias-- in what situations is mortality higher? (timing) what is the highest mortality situation?mortality is higher when hernias are repaired < 24 hours, or > 1 year after occurrence. repairs carried out within the first 24 hrs May have the highest mortality rate, if not adequately stabilized
seeing bowels beyond the _________ ICS is something to note8th (esp if ventral)
how might the thorax change radiographically if there is fluid in it?lung lobes more distinguished, heart silhouette shadowed

Repairing D hernia

Question Answer
*how can you really inc the success rate of repairing D hernia? and why?delaying sx 1-2 weeks --> success rate 90%!!!! bc stabilization of patient and edges of rib into diaphragm will be partially healed and stronger tissue to place bites
*when is it an emergency and you absolutely can't wait to fix the D hernia?If the stomach has herniated into the thoracic cavity, surgery must be done immediately. This is bc A dilating stomach will cause complete and rapid collapse of the lungs
what things should anesthesia be mindful of/do when inducing/maintaining during D hernia sx?pre-oxygenate pt, minimize stress and rapid induction, avoid drugs that depress respiration!! controlled respiration- mechanical or manual, avoid over-inflation of lungs
for repair of D hernia, which approach is generally better/preferred?Do ABDOMINAL approach, NOT thoracic!
Pros and cons of abdominal approach to repair of hernia?PROS: more familiarized, provides bilateral access, can be extended by sternotomy or paracostal incision. CONS: requires ventilatory support of patient
Pros and cons of thoracic approach to repair of hernia?PROS: good visualization, suture over convex surface. CONS: only one side / accurate Dx! need experience with thoracic Sx
describe the sx technique for repairing a D herniaGently retract herniated viscera into abdomen--> If viscera are adhered in thorax, extend incision cranially and break up adhesions by sharp and blunt dissection under direct visualization--> Begin suturing radial tear at most dorsal margin/ Anchor circumferential tears by suturing around ribs
where (directionally) do you want to start suturing if it is a radial tear?most dorsal margin
how can you anchor/suture down a circumferential tear which pulled away from the ribs?Anchor circumferential tears by suturing around ribs
If the liver/liver lobes have gone through hernia, what structure should you be esp. careful of when trying to replace?phrenic nerves, because you often need to enlarge opening to replace it
if you are fixing a D hernia and you see this white stuff on the liver, what do you think is going on? This is fibrin which is excreted from the liver capsule and can cause adhesions
when repairing the D hernia, be careful not to pierce through what blood vessel?Vena cava!
If you accidentally break liver when trying to replace it, what can happen?chemical peritonitis
once you have finished replacing things, and you are ready to expand the lungs, in what manner should you expand them?SLOWLY- to prevent pulmonary edema ddue to reperfusion injury
in what direction should you close the hernia, and what stitch does he prefer? what can you do with your suture to make your life easier?from distal to proximal - place first stitch close to vena cava- dont pierce it. he like cruciates- leave long tag- helps to bring edges of diaphragm up in order to assist stitching better. can place lap sponge btwn liver and diaphragm!
what type of suture material can you use to close the D hernia?Non-absorbable suture, can also use nylon or prolene
what suture patterns can you use to close?simple continuous or simple interupted (he said he liked cruciate too)
If a primary closure if not possible (say the diaphragm is blown out and there is no way to appose the edges) what can you do? (2)(1) Use autogenous or synthetic graft. Examples include fascia lata (he didn't like this), Muscular pedicle graft from abdominal wall (can create a mm flap from triversus abd mm. can also use liver if hole not too big.), Omental pedicle flap (omentum if defect not too big), Teflon or Silastic sheeting (2) Advance diaphragm-- can displace diaphragm cranial- suture it around ribs like said before- if have to get rid of big section of diaphragm or last ribs. ok for resp capacity
mm pedicle graft technique of patching if can't do 1* closure... (pic)
what is the last ditch salvage procedure if the diaphragm can't be fixed, and what is the downside to this?get rid of diaphragm and turn into a celomic cavity- this is not so awesome though bc if you need to open the abdomen the pt will have to be on a ventilator
how does the prolene mesh repair kinda work?works like a scaffold (infilatreted by RBCs and fibroblasts)- and once fleshed out, will work like the diaphragm
what mistake do people often make when trying to restore neg pressure to thoracic cavity?with last stitch introduce cath to remove air.... before last stitch tied...then ask anesthetist to inflate lungs but already closed ...he says alveoli will explode.
after sx what kinda tubes should you place?thoracostomy tube
With chronic hernia or herniated liver, what else will you have to do after the sx?drainage may be required for several days
during postop, you will need Careful constant monitoring of patient because of what 4 things?(1) Risk of reperfusion injury (2) Risk of re-expansion pulmonary edema (3) Risk of hemorrhage/bleeders (4) Risk of pneumothorax
When is the prog of the sx guarded, and when is it excellent?GUARDED: until patient has survived 24 hours following surgery. EXCELLENT: if patient survives first 24 hours following surgery (reported survival rate is 60-90%)
most deaths related to D hernia occur when? what has the highest impact on mortality rate?pre-operatively. Many also occur during induction. Pre and post-operative management have greatest impact on mortality rate

not D. hernias

Question Answer
how does the Paracostal hernia appear radiographically?
which stitch does he like to use to repair Paracostal hernia?cruciate
what is the etiology of the Peritoneo-pericardial hernia?In dogs and cats, always congenital!!
The Peritoneo-pericardial hernia is Often associated with what other problems?cardiac abnormalities and sternal deformities
in a Peritoneo-pericardial hernia, where are the abdominal organs displaced to?Abdominal organs inside *pericardial cavity
what are the clinical signs of a PP hernia?patients are often asymptomatic! (signs may be variable and intermittent). cardiac murmur, right heart insufficiency, muffled heart sounds
which part of the heart is often insufficient with a PP hernia?right heart
how will the ECG be affected with a PP hernia?low voltage
congenital associated defects with the PP hernia? (3)(1) ventral / umbilical hernia (2) cardiac defects (3) lack of union of the last sternebra (*assocaited with ventral hernia in 4/13 dogs)
some ancillary dx techniques for PP hernia?survey radiograph, contrast radiograph (GI transit/celiography), US
5 radiographic signs of Peritoneao-pericardia hernia?(1) enlarged cardiac silhouette (2) discontinued ventral diaphragm (3) structures with gas in pericardial sac (4) sternum defects (5) tracheal elevation
how do you sx repair a PP hernia?Abdominal approach to diaphragm--> Relocate abdominal viscera--> Debride edges of defect and close from dorsal to ventral
in what direction do you close a PP hernia?from dorsal to ventral
for a PP hernia, which approach to the diaphragm do you wanna do?abd
****what should you NOT DO when repairing a PP hernia?Do not close pericardial sac
in order to fix PPH, you must increase the defect size to allow reduction. what is the sequale to this (so what must you do?)--> communication w’ pleural cavity. This means you will need assisted ventilation, thoracic drainage, intensive care for 24-48 hs