Diaphragmatic Rupture in Cats: Nacho’s Story

Any cat who goes outdoors risks being hit by a car. Injury from this kind of trauma isn’t always obvious, as was the case with a cat named Nacho.

Outdoor cats are at high risk for traffic accidents. By: swobes

What is it about Friday nights?

My regular on-call night happens to be a Friday. Perhaps it’s because people are out enjoying themselves after a week at work, but in my mind Friday nights are trauma nights. And this Friday was no different.

I’d been home from work for 30 minutes when the phone rang. I recognized the client’s voice right away: a devoted cat lover. Her voice was shaky with emotion. Nacho, her Bengal-cross, had been missing, but he’d just come home and was having difficulty breathing.


When she arrived at the clinic, she lifted Nacho from a basket. “I’m so sorry for calling you. I’m sure it’s nothing, really,” she said, her voice quivering. On the table, Nacho rested on his stomach staring straight ahead, taking deep, heaving breaths.

I checked him over. Remarkably, the only outward signs of trauma were scuffed nails. Looking for that is an old vet trick — scuffed claws are a sign the pet was pushed along an abrasive surface, such as when a vehicle strikes a cat.

Listening to Nacho’s chest, I found his heart to be unusually muffled, and his tummy felt strangely empty. The signs were beginning to point in one direction: a diaphragmatic rupture.

What Is a Diaphragmatic Rupture?

Have you ever had hiccups? Well, that’s your diaphragm misbehaving.

This dome of muscle separates the abdomen from the chest with an air-tight seal. The idea is when you breathe in, the chest expands and the diaphragm flattens, which draws air into the lungs.

A blow or a fall causes a sudden increase in pressure that can rip or tear the diaphragm. Like a door left ajar, this allows movement from one room to another. In the case of a diaphragmatic rupture, this means the liver, spleen or stomach (or, in severe cases, all of them) pop forward into the chest.

Having a chest full of gut squashes the lungs and stops them from filling with air, so animals with a diaphragmatic rupture have trouble breathing. In the short term they often don’t want to eat, and in the long term all sorts of wacky things happen with fluid that leaks around the lungs and puts even more pressure on breathing.

Diaphragmatic ruptures can leave cats out of breath. By: htakashi

Helping Nacho

Diaphragmatic ruptures are serious and need surgical correction, but not right away. A cat involved in a recent trauma is likely to also have a bruised heart and lungs, which increases the anesthetic risk.

I admitted Nacho for the weekend to stabilize him by giving pain relief, oxygen and intravenous fluids. This helped build his strength for an investigation and surgery on Monday morning.


Radiographs are a neat way to confirm a suspicion of diaphragmatic rupture.

An X-ray plate of a pet lying sideways usually shows the diaphragm as a clean line of demarcation dividing the chest from the tummy. In Nacho’s case, his X-rays showed no such line, and indeed there was a gas shadow in his chest that was consistent with a misplaced stomach.

With the diagnosis confirmed, the team sprang into action for some high-risk surgery. The problem is, as soon as an incision is made into the abdomen, air rushes in and collapses the lungs. This means the patient can no longer breathe for himself and needs intermittent positive pressure ventilation (IPPV). The cat must be connected to oxygen via a tube in his windpipe, and a vet tech breathes for the cat by pressing on the anesthetic bag.

Unfortunately, the complications of such surgery include:

  • Death from a heart attack
  • Never regaining consciousness


This was a real team effort with one vet tech assigned to breathing for Nacho and another monitoring the anesthetic, leaving me free to repair the damage.

Nacho had not 1 but 2 tears in his diaphragm. In fact, the diaphragm had detached from the ribs for around 50% of its circumference.

But there’s nothing quite like a challenge to make you rise to the occasion, and happily the surgery went well. With the repair complete, next was that nail-biting moment when we turned off the anesthetic gas and waited for the patient to start breathing for himself.

Fortunately, Nacho did just that.


Nacho remained unfazed by his surgery and went on to make a full recovery. His checkups were tricky because he was soon back to his old self, patrolling round the consult room and refusing to stay still.

However, a good thing came of all this: Nacho is no longer interested in the outside world and prefers to stay home rather than investigate the great outdoors.


This pet health content was written by a veterinarian, Dr. Pippa Elliott, BVMS, MRCVS. It was last reviewed Dec. 17, 2018.